Tuesday, June 30, 2009

Structural instability (injury to common stabilizing vertebral structures) compensated by muscular stabilization in neutral zone




Because of the direct attachment to the vertebrae, both passive and active strain from the musculature influence the spinal kinematics in normal or destabilized motion segments. Kinetic behavior of the spine refers to studies of the spine motions. Kinetic behavior & stability not only of the spinal motions is studied extensively but also the neutral region is studied. A transition zone for example between spine movements such as flexion & extension occurs is called the neutral region.

Segmental instability in the lumbar spine is associated with abnormal intervertebral motion. Most of biomechanical studies have studied the common stabilizing structures i.e., intervertebral disc, facet joints, and ligaments and have not simultaneously considered the effects of active musculature on spinal kinematics. Recent researches reveal that:

1. Axial translation increases in response to injuries to the disc.
2. Sagittal rotation and shear translation changes in response graded injuries to the facet joint.
3. Significantly increased coupled motion and rotation in neutral region in injury of the facet + transverse processes

Injuries to the common stabilizing structures increase the range of motion. But increased muscular activity stabilizes the injured motion segment by smoothing the erratic rotation pattern of motion, particularly in the neutral region. Surgeons & rehabilitation specialists dealing with facetectomy must take a special note of it.

Reference:

Kaigle AM et al; Spine. 1995 Feb 15;20(4):421-30.


Saturday, June 27, 2009

Lumbar disc behavior under static & vibratory loading & it’s implications on spinal movement




The following Part of another my review…………

Lumbar disc herniations can be a direct mechanical consequence of prolonged sitting in static or vibration environments that challenges the stability of this region.

Static loading: A 1 hour exposure to static lumbar loading such as sitting cause significant changes in the mechanical properties of the lumbar intervertebral disc exhibited by a sudden, large flexion and/or lateral bend rotation response to an axially applied load. This further implies that a motion segment in the lumbar spine suddenly buckles and applies a tensile impact loading to the posterolateral region of the disc.

Vibratory loading (Driving a car, truck, tractor etc): A combined lateral bend, flexion, and axial rotation vibration loading could cause tracking tears proceeding from the nucleus through the posterolateral region of the annulus.

Mechanical impacts of static & vibratory loading on disc reveal that mechanism for disc herniation is mechanical change leading to instability of the motion segment.

Reference:
Wilder DG et al; J Spinal Disord. 1988;1(1):16-32.


Tuesday, June 23, 2009

Grades of mobilization by PA technique: Inter-therapist variances




There is no gold standard for measurement of magnitude of force applied or joint displacement. Many scientific tools & methodologies have been used to measure quantity of force applied by manual therapy procedures and joint displacement thus caused. Among these equipments some serve to mobilize the spine others serve as measurement tools for mobilization.

Different grades of mobilization have helped manual therapists to compartmentalize the quality & quantity of the energy package they provide to the receptive tissue. Having said so the general feeling is that, grades of mobilization helps in this regard only partially, because standardization of delivery can not be warranted for it is individualistic and dependant on the therapist. Therapist centered module delivery is dependant on many factors so inter-therapist variance is quite inevitable.

The PA mobilization: PA technique of spinal mobilization is both a diagnostic & therapeutic tool. Both subject & instrument oriented tests for the reliability of physical therapists' ability to detect intervertebral motion have confirmed unreliable testing in the face of documented efficacy of manual treatment via PA spinal mobilization.

However, despite the widespread use of spinal mobilization, little is known about the forces used or the accuracy of therapists in estimating the forces they use in administering the technique (1). In the following discussion we would like to throw light on the issue.

1. Study of Simmonds & colleagues (1995): In this study therapist applied oscillatory posteroanterior (PA) mobilizations to the mechanical model under three different conditions of stiffness for following purposes:

  • To quantify the forces used by therapists
  • To determine the accuracy of therapists in applying these forces

The findings are as follows:

  • Average forces across grades and stiffness levels = (57.59 to 178.27) Newton
  • Lower the stiffness lower is the force applied
  • Displacement varied with stiffness and mobilization grade. In the least stiff condition, the mean displacement varied between 2.25 and 3.45 mm for grades 1 to 4, respectively.

2. Review of Snodgrass & colleagues (2006): Snodgrass & colleagues reviewed 6 electronic databases up to April 2005 comprising of 20 studies of quantitative measurement of applied force during a PA mobilization technique mostly focusing on the lumbar spine in order to find out

  • Evaluate the consistency of force application by manual therapists when carrying out posterior-to-anterior (PA) mobilization techniques.
  • Factors that influence the application and measurement of mobilization forces.

They found when defined by magnitude, frequency, amplitude, and displacement:

  • PA mobilization forces are extremely variable among clinicians applying the same manual technique.
  • Variability is attributed to differences in techniques, measurement or reporting procedures, or variations between therapists or between patients.

Summary:

1. Inter-therapist variability is high in manual therapy procedures be it a commonly applied technique i.e. PA mobilization (1,2). This further warranty improvement in the clinical standardization of manual force application.
2. There is a systematic bias in underestimating the magnitude of applied force and in overestimating motion. The variability in force application and the general overestimation of motion detection leads to poor reliability of measurements obtained with clinical tests based on motion palpation (1).

Addressing the research gap:

Future research on mobilization should include forces applied to the cervical and thoracic spines in addition to the lumbar spine while thoroughly describing force parameters and measurement methods to facilitate comparison between studies (2).


References: 1. Simmonds MJ et al; Phys Ther. 1995 Mar;75(3):212-22. 2. Snodgrass SJ et al; J Manipulative Physiol Ther. 2006 May;29(4):316-29. 3. Björnsdóttir SV et al; Disabil Rehabil. 1997 Feb;19(2):39-46.

Saturday, June 20, 2009

Spine manipulation: the HVLA technique


Spinal manipulation (SM) is a popular form of manual therapy used by variety of manual medicine practitioners to treat patients with low back and neck pain. The HVLA or the high velocity low amplitude thrust technique is one the most common form of SM application. HVLA characterized by following:

1. High-velocity (duration less than 150 ms),
2. low-amplitude (segmental translation less than 2 mm, rotation less than 4 degrees , and applied force 220-889 N)
3. Impulse thrust.

The skill set for success in applying an HVLA-SM lies in the practitioner's ability to

1. Control the duration and magnitude of the load (ie, the rate of loading).
2. The direction in which the load is applied.
3. The contact point at which the load is applied.

Clinical effects are highly dependant on the control over its mechanical delivery. This procedures set up biomechanical changes & that is responsible for physiological consequences especially by changes in sensory signaling from paraspinal tissues (6).

Effects of altering the duration of loading & amplitude of loading on spindle discharge: Reports from animal models (6).

Anesthetized cats ware subjected to Impulse thrusts of duration: 12.5, 25, 50, 100, 200, and 400 ms; amplitude 1 or 2 mm. These thrusts are posterior to anterior applied to the spinous process of the L6 vertebra of the cat. The finding of different amplitude & duration of thrust are as follows:

1. As thrust duration became shorter, the discharge of the lumbar paraspinal muscle spindles increased in a curvilinear fashion. A concave-up inflection occurred near the 100-ms duration eliciting both a higher frequency discharge compared with the longer durations and a substantially faster rate of change as thrust duration was shortened. This pattern was evident in paraspinal afferents with receptive fields both close and far from the midline.

2. Paradoxically, spindle afferents were almost twice as sensitive to the 1-mm compared with the 2-mm amplitude thrust.

These findings suggest that with HVLA thrust the sensory system in connection to paraspinal muscle spindle is stimulated more. Clinically, these parameters may be important determinants of an HVLA-SM's therapeutic benefit.

Reference:
Pickar JG et al; Spine J. 2007 Sep-Oct;7(5):583-95. Epub 2007 Jan 10.

Friday, June 19, 2009

Criteria for Classification Of AS




I. Calin Criteria (inflammatory back pain)
Four out of 5 must be present:
  1. Age <40
  2. Back pain >3 months
  3. Insidious onset
  4. Improvement with exercise
  5. Early morning stiffness.

II. Rudwaleit criteria (axial spondyloarthropathy)
A positive likelihood ratio of 3.7 is achieved if 2 of 4 criteria are present and increases to 12.4 if 3 of 4 criteria are present:

  1. Morning stiffness >30 minutes
  2. Improvement in back pain with exercise but not with rest
  3. Awakening in the second half of the night because of back pain
  4. Alternating buttock pain.

III. Modified New York criteria for classification
Definite AS if criterion 4 and any one of the other criteria are fulfilled.

  1. Low back pain of at least 3 months' duration that is improved by exercise and not relieved by rest.
  2. Limited lumbar spinal motion in sagittal and frontal planes.
  3. Chest expansion decreased relative to normal values for sex and age.
  4. Bilateral sacroiliitis grade 2 to 4, or unilateral sacroiliitis grade 3 or 4.

IV. European Spondyloarthropathy Study Group (ESSG) criteria
Inflammatory spinal pain or synovitis is:
• Asymmetrical or
• Predominantly in the lower limbs
and 1 or more of the following:
  1. Alternate buttock pain
  2. Sacroiliitis
  3. Enthesitis (inflammation of the tendon or ligament attachments to bone)
  4. Positive FHx spondyloarthropathy
  5. Psoriasis
  6. Inflammatory bowel disease
  7. Urethritis or cervicitis or acute diarrhoea occurring within 1 month before arthritis.
V. Amor criteria
Diagnosis of spondyloarthropathy with 6 or more points:

  1. Inflammatory back pain (1 point)
  2. Unilateral buttock pain (1 point)
  3. Alternating buttock pain (2 points)
  4. Enthesitis (inflammation of the tendon or ligament attachments to bone) (2 points)
  5. Peripheral arthritis (2 points)
  6. Dactylitis (2 points)
  7. Acute anterior uveitis (2 points)
  8. HLA-B27 positive or FHx of spondyloarthropathy (2 points)
  9. Good response to NSAIDs (2 points).

Monday, June 15, 2009

TBC- Treatment based classification for LBA


Background (Need of TBC):


Similar pathologies presenting with similar clinical features do not respond to similar physiotherapy treatment methods, rather to different physiotherapeutic treatment strategies. Fritz reported 3 patients; each patient had signs and symptoms of compressive nerve root pathology with a similar anatomical distribution of pain. However, basing on TBC (Treatment based classification), each patient was treated with a different approach based on the assigned classification. One patient was classified as needing treatment for a lateral shift, one patient was classified as needing flexion-oriented treatment, and the other patient was classified as needing extension-oriented treatment. The approach used for each patient was successful in reducing patient-reported pain severity and level of functional disability (4).

Introduction:

Classification of patients with low back pain into homogeneous subgroups has been identified (3). Further the development of valid classification methods to assist the physical therapy management of patients with low back pain has been recognized as a research priority. There is also growing evidence that the use of a classification approach to physical therapy results in better clinical outcomes than the use of alternative management approaches (2).

Treatment based on severity of presentation (1):

For LBA entire approach taken by physiotherapists now days is diagnosis based, with specific algorithms and decision rules. Further working in the above said line consistent CPR i.e. clinical prediction rules are also chucked out. However, the causal approach to LBA patients is via historical information, behavior of symptoms, and clinical signs. Most patients can be managed by conservative care are managed predominantly and independently by physical therapists, but still a good deal of patients require other services e.g. psychology or who require referral because of possible serious nonmusculoskeletal pathology.

Physical therapists classify the patients who can be managed by them into 3 stages according to severity of the presentation:

1. Stage I for patients in the acute phase where the therapeutic goal is symptom relief
2. Stage II for patients in a sub-acute phase where symptom relief and quick return to normal function are encouraged and
3. Stage III for selected patients who must return to activities requiring high physical demands and who demonstrate a lack of physical conditioning necessary to perform the desired activities safely.

Further, classification for stage I patients can be further classified into distinct categories that are treatment-based and that specifically guide conservative management.

The treatment based classification (TBC):

Many authorities in past called LBA are a non-specific clinical presentation. However, emerging evidence suggests that there are clearly defined subgroups and respond differently to conservative non-pharmacological treatment, challenging the assertion that LBP is "nonspecific." (5) So, there is emergence of TBC or Treatment-Based Classification. First time Delitto and colleagues, (1995) proposed such 4 level TBC classification system. According to Treatment-Based Classification there are 4 categories of treatment applied to the classified subgroups. These 4 categories of treatments are:

1. Stabilization
2. Mobilization
3. Direction specific exercise or
4. Traction

Each classification could be identified by a unique set of examination criteria, and was associated with an intervention strategy believed to result in the best outcomes for the patient (2). However researchers have found that impairments of the transverse abdominis and lumbar multifidus occur across all subgroups of LBP (5).

Benefits of treatment based classification:

1. Clarification of the unsolved aspects of LBA especially in management aspect.
2. Numerous clinical exploratory researches have emerged to clarify more on this issue.
3. The development of clinical prediction rules regarding the context.
4. Providing new evidence for the examination criteria and optimal intervention strategies for each classification.
5. Incorporation of new clinical into existing classification systems.

Reliability & outcomes of physical therapy treatment when a TBC is used:

Fritz & colleagues concluded in their study analyzing interrater reliability on 120 patients:
1. Reaching a consensus regarding relevant patient subgroups requires data on the reliability and validity of existing classification systems.
2. Further work is required to validate improvement in treatment outcomes using a classification approach.

References:

1. Delitto A et al; Phys Ther. 1995 Jun;75(6):470-85; discussion 485-9.
2. Fritz JM et al; J Orthop Sports Phys Ther. 2007 Jun;37(6):290-302.
3. Fritz JM et al; Spine. 2000 Jan;25(1):106-14.
4. Fritz JM; Phys Ther. 1998 Jul;78(7):766-77.
5. Kiesel KB et al; J Orthop Sports Phys Ther. 2007 Oct;37(10):596-607.


Sunday, June 14, 2009

What RUSI answars in LBA cases

According to Knudson HA (a doctor of physical therapy) real time ultrasound imaging can provide answer all of the following questions or identify the following problems associated with LBA.

1. Test voluntary activation through conscious effort. Identify change in motor control in individuals with low back pain. If muscle wasting is identified, what is the % difference between sides of the specific segment? Identify unilateral muscle wasting within a specific segment of lumbar multifidus. Is the patient able to consciously contract lumbar multifidus while in an unloaded position without trunk movement or limb loading? Can the patient emphasize activation of deep fibers of multifidus while limiting activation of superficial fibers? (Poor quality of lumbar multifidus contraction?) Does the muscle composition of multifidus look healthy, without fatty infiltrate, fluid from injury, fibrosis, soft tissue adhesions, or calcium deposits?

2. Does the patient display one of 5 clinical patterns of transversus abdominis dysfunction during testing for the automatic recruitment strategy used by the nervous system to control the trunk? Observe the automatic recruitment strategy to identify normal or abnormal control of transverse abdominis during load transfer involving movement of limbs. Is the patient able to maintain a tonic hold of transverse abdominis without movement of the spine during testing for conscious activation?

3. How long can a patient sustain a transverse abdominis or lumbar multifidus contraction before fatiguing? Can the patient co-contract transverse abdominis and lumbar multifidus, independent of the global superficial muscles of the back/abdomen?

4. When the patient draws in the lower abdomen, how much of a linear change in lateral pull of the fascia attachment occurs from rest to active without significant internal obliques thickness increase and with minimal transverse abdominis thickness increase? Does the patient have automatic tonic contraction occurring with movement?

Reference:

www.back-exercises.com

Saturday, June 13, 2009

Rehabilitative Ultrasound imaging (RUSI): what is coming ahead in physiotherapy!!!


Following is a part of a review that is for a journal.

Background:
The use of ultrasound imaging by physical therapists is growing in popularity (21). A special issue of the JOSPT (journal of sports physical therapy) in 2007 has been released on collection of commentaries, case reports, and research reports that document current applications and evidence for rehabilitative ultrasound imaging (RUSI) in patients with neuromusculoskeletal disorders. Professor Maria Stokes of Southampton university of UK is a renowned researcher in the field of neuro-rehabilitation has put much of her efforts in researching on RUSI. According to Professor Maria Stokes there is a need of development of investigative & rehabilitation techniques for the following purposes:

1. Provide accurate, objective tools to aid clinical assessment and motor recovery.
2. Provide valid and reliable investigative tools for research to examine mechanisms of neuromuscular function & to examine the effectiveness of treatments.
3. Provide biofeedback to aid rehabilitation.

According to Prof. Stokes 3 currently emerging prominent rehabilitative tools to accomplish above said purposes are:

1. Rehabilitative Ultrasound imaging (RUSI)
2. Brain Computer Interfacing (BCI)
3. Mechanomyography (MMG)


Our current focus of this discussion is RUSI or the Rehabilitative Ultrasound imaging. According to Jackie & colleagues RUSI is an emerging tool in physical therapy profession which relates to the larger field of medical ultrasound imaging. Further they recommended to physiotherapists in this specialized area to possess knowledge on basic ultrasound imaging and instrumentation principles, including an understanding of the various modes and applications of the technology with respect to neuromusculoskeletal rehabilitation.

Introduction to RUSI: Ultrasound imaging offers a safe, non-invasive, objective and relatively inexpensive means of examining muscle. This use of ultrasound, now termed RUSI, is distinct from the diagnostic use of ultrasound for musculoskeletal conditions.

Its use by physiotherapists was formally established as a specialist field within medical imaging in 2006 at an International Symposium held in Texas (Whittaker et al., 2007). This Symposium aimed to set international guidelines for clinical practice, research and training of physiotherapists in ultrasound imaging in rehabilitative musculoskeletal conditions. Professor Maria Stokes runs an introductory course in RUSI for physiotherapists in collaboration with a Specialist Sonographer.

Several muscles such as Lumbar Multifidus, Abdominal muscles, Posterior neck muscles, Quadriceps, Anterior tibial muscles, Masseter, Trapezius have been studied by various researchers (See Images of these muscles at www.southampton.ac.uk/.../mariastokes.html) and the technique is used in various studies of disorders involving muscle dysfunction. An example of RUSI as a biofeedback tool is for observing the changes in the abdominal muscles as they contract.

References:
1. www.southampton.ac.uk/.../mariastokes.html
2. www.maherpt.com/rtus.aspx

3. Teyhen DS; J Orthop Sports Phys Ther. 2007:37(8):431-433.
4. Jackie L et al; J Orthop Sports Phys Ther. 2007:37(8):434-449; published online 30 May 2007.




Wednesday, June 10, 2009

Sprain of lateral Chopart (calcaneocuboid) joint








Anatomy:

The midtarsal or transverse tarsai joint is comprised of two separate joints: the Talocalcaneonavicular and the Calcaneocuboid. The Calcaneocuboid Joint is formed by the articulation between the calcaneus and the cuboid. 3 primary ligaments support the Calcaneocuboid joint. They are: Dorsal Calcaneocuboid Ligament, Lateral or calcaneocuboid portion of the Bifurcated Ligament & Plantar Calcaneocuboid Ligament, a dense, thick, white structure consisting of two distinct layers.

2 layers of Plantar Calcaneocuboid Ligament are: Deep layer, runs from anterior tubercle of calcaneus to plantar surface of cuboid posterior to groove for peroneus iongus. Also known as the short plantar ligament Superficial layer, arises from calcaneus and inserts into cuboid bone continuing in anterior direction, forming tunnel for peroneus longus (PL) and finally inserting into the 5th, 4th, 3rd, and on occasion 2nd metatarsal heads.

Injury:
Involvement of calcaneo-cuboid joint is a rare entity. This sprain is commonly associated with inversion forces & sprain of LCL of ankle. The selective rupture of the calcaneocuboid ligament is extremely rare and frequently misdiagnosed (1, 2). The calcaneocuboid ligament sprain is confused with Peronius longus tendonitis. Many times the cuboid is subluxed where the pain may come from all the ligaments but more on the planter ligaments of the CC joints. Extreme injuries such as rupture of CC ligaments is although rare yet reported in 5 % cases of supination trauma in the ankle joint and foot (1).

X-ray with varus stress and in certain cases of computer tomography (CT) and magnetic resonance imaging (MRI), beside the routine antero-posterior and lateral views, is emphasized. Comparative X-rays (of normal & involved sides) plays a key role in diagnosis.

Classification of the injury by X-ray with varus stress:
1. Type 1: Calcaneocuboid angle less than 10 degrees without a bony flake.
2. Type 2: Calcaneocuboid angle more than 10 degrees with or without a bony flake.
3. Type 3: Calcaneocuboid angle more than 10 degrees with big bony flake.
4. Type 4: Complex injuries = cuboid compression fracture + ligament rupture.

Principles of management:
According to Lindner & collagues, surgical treatment does not appear to be necessary. 4-week immobilisation by cast is sufficient for elimination of complaints and restoration of adequate functionality. However Andermahr & colleagues recommend:

1. Strapping for 6 weeks in type 1 variety.
2. Shoe cast for 6 weeks in type 2 variety. And if there are persistent symptoms a secondary peroneus brevis tendon graft is done.
3. Type 3 variety should be treated by open reduction and refixation of the ligament.
However there is no mention of treatment about the Complex type 4 injuries by Andermahr.

References:

1. Lindner HO et al; Zentralbl Chir. 1986;111(20):1250-4.
2. Andermahr J et al; Foot Ankle Int. 2000 May;21(5):379-84.
3. Grey’s anatomy


Preamble to Sacral neuromodulation


Key words: sacral nerve stimulation, sacral neuromodulation, pelvic floor dysfunction, voiding dysfunction

Sacral neuromodulation provides a new option for the management of voiding dysfunction. Tanagho and Schmidt first introduced sacral nerve neuromodulation in 1981 (2,3). Tanagho and Schmidt implanted the stimulator to treat voiding disorders like urinary urge incontinence, urgency-frequency, and nonobstructive urinary retention (3). For patients with voiding disorders, this procedure has resulted in significant improvement in urinary frequency, voided volume and pelvic pain (1).
However since then, it has become increasingly popular and the indications for this procedure are growing well beyond just voiding disorders. These additional benefits have included re-establishment of pelvic floor muscle awareness, resolution of pelvic floor muscle tension and pain, decrease in vestibulitis and vulvadynia, decrease in bladder pain (interstitial cystitis), and normalization of bowel function (3).

According to Pettit & colleagues following are the recent findings (3):

1. Fecal incontinence: Therapy for fecal incontinence in patients with a structurally intact sphincter mechanism appears to be very promising. Investigators agree that there is a role for sacral nerve stimulation in patients with urge fecal incontinence that have failed conservative efforts. Objective manovolumetric testing shows an increase in resting pressure, an increase in voluntary contraction pressure, a decrease in rectal volumes which cause first urge, a decrease in rectal volume to initiate first urge to defecate, and an increase in duration of maximum squeeze pressure.

2. Interstitial cystitis: Intractable interstitial cystitis is defined as patients that have failed conventional therapy. Historically, the only option remaining was surgery or diversion. Maher et al. reported on patients with intractable interstitial cystitis who had undergone sacral nerve stimulation. They found that 73% of these patients had a reduction in pelvic pain, daytime frequency, nocturnal urgency and an increase in average voided volumes.

3. Chronic refractory pelvic pain: The final area of interest concerns refractory pelvic pain. Siegal et al. reported a decrease in severity, number of hours of pain, and improved quality of life measures in patients who underwent transforamenal sacral nerve stimulations. These patients had all failed conventional pain therapy.

However there is promise in this module of treatment but much of the research is yet to come.

Sacral nerve stimulation in Pelvic floor dysfunction:

Pelvic floor dysfunction is a complex problem that can be refractory to current treatment modalities; even with surgery the out come is unsatisfactory & sub-optimal (4). According to Aboseif & colleagues sacral nerve stimulation is an effective and durable new approach to pelvic floor dysfunction with minimal complications where they recommend a test stimulation as a guide to for patient selection.

Sacral nerve stimulation in anal pain:

Chronic idiopathic anal pain is a common, benign symptom, the etiology of which remains unclear. Traditional treatments are often ineffective (5). Falletto & colleagues found in long-term relief of pain & positive improvement in quality of life in their patients. Many authors believe that SNS must be tried before adopting more aggressive surgical procedures for patients with chronic idiopathic anal pain even in whom pharmacologic and biofeedback treatments have failed to produce effective results.

References:

1. Johnson DN et al; W V Med J. 2003 May-Jun;99(3):111-3.
2. Hassouna M et al; Curr Urol Rep. 2003 Oct;4(5):391-8.
3. Pettit PD et al ; Curr Opin Obstet Gynecol. 2002 Oct;14(5):521-5.
4. Aboseif S et al; Urology. 2002 Jul;60(1):52-6.
5. Falletto E et al ; Dis Colon Rectum. 2009 Mar;52(3):456-62.







Sunday, June 7, 2009

ANS activity & Depth of massage


Massage can be of various depths. It can be superficial or penetrating to quite a tissue depth. How ever studies on what effect different depth of massages produce on ANS activity are not studied largely. Recently Diego & colleagues of Touch Research Institute of Florida, USA explored the same. They took HRV (heart rate variability) as the indicator for ANS activity. This study found:

1. Effect of moderate pressure massage:

Moderate pressure massage elicits a parasympathetic nervous system response suggesting increased vagal efferent activity. Further, there is shift from sympathetic to parasympathetic activity that peaked during the first half of the massage period.

2. Effect of light pressure massage:

On the other hand, those who received the light pressure massage exhibited a sympathetic nervous system response.

Blooger’s Comments: the following must be noted.

Caution: Massages are generally perceived to be safe. However the carry over ANS effects of moderate depth is not explored. What happens if applied in cardiac patients where there is either sympathetic or parasympathetic dominance? Please try to explore before recommending such modalities or am I overcautious.

Reference: Diego et al; Int J Neurosci. 2009;119(5):630-8.

10+ 10+ 10 = 30 min or 30 min at a time? Accumulated versus continuous exercise for health benefits


Introduction to the debate – short bout or long drawn exercise:

Current physical activity guidelines endorse the notion that the recommended amount of daily physical activity can be accumulated in short bouts performed over the course of a day. Metabolic impacts of exercises are specific; so training impacts are also specific which vary with duration & intensity & fuel ingestion.

Aerobic exercise is low to medium output held for an extended period. Anaerobic or supra-aerobic exercise is high output, but short in duration. Dr Alsears (USA) recommends supra-aerobic exercise than to aerobic exercise for following training benefits:

1. Lose pounds of belly fat
2. Build functional new muscle
3. Reverse heart disease
4. Build energy reserves available on demand
5. Strengthen immune system
6. Reverse many of the changes of aging.

Dr Alsears of USA calls his program PACE® program. The following prototype is similar to PACE program:

1. Instead of a slow, steady pace on a bicycle or treadmill, try going 80% of your maximum for 2 minutes.
2. Rest for 1 minute
3. Go at 90% for another two minutes
4. Rest for 1 minute
5. Go at 100% for 1 minute
6. Recover

This program is an example of an intermittent training program. Intermittent training is aimed at anaerobic system developments especially for speed, which rarely induces aerobic training benefits of fat reduction. However, note that this program also claims to reduce body fat. Reduction of undue fat is associated with reduction of numerous biological & organic risks pertaining to fat accumulation.

We want to emphasize that, the metabolic switchover to aerobic exercises occurs between 2-3 minutes & efficient fuel utilizations in terms of FFA & TG occurs much later as carbohydrate has to go through the metabolic mill i.e. the TCA cycle fragments of carbohydrate must be present to start the lipid oxidation.

The confusion & the question:

First impression about short duration exercises is in the line of interval training not continuous training. It is taught to us that continuous training is the aerobic training & interval training is more anaerobic training. So how it is possible to get benefits of short bouts of similar to long drawn exercises. “Is there some logic behind it?” this question itched my mind long. As low duration exercises are directly related to a high patient compliance. When I read cumulative effects of short duration exercises is as good as a long drawn exercise I was encouraged to write this article.

The research article by Murphy et al (sports medicine; 2009):

The evidence on the claim that efficacy of accumulated exercises to that of continuous exercise is similar is limited. Murphy & colleagues reviewed (16 studies with before & after evaluation are included) to compare the effects of similar amounts of exercise performed in either one continuous or two or more accumulated bouts on a range of health outcomes. The important points to note are as follows:

A. Review of Long term studies reveals:

1. Impact on cardiovascular fitness: most studies reported no difference in the alterations between accumulated and continuous patterns of exercise.
2. Impact on normalization of BP: there appear to be no differences between accumulated and continuous exercise in the magnitude of this effect.
3. Impact on adiposity, blood lipids and psychological well-being: there is insufficient evidence to determine whether accumulated exercise is as effective as the more traditional continuous approach.

B. Review of Short-term studies reveals:

Murphy & colleagues also studied 7 short-term studies with before & after evaluations. Most of the studies considered the plasma TG response to a meal following either accumulated short or continuous bouts of exercise. Short term studies also suggest that accumulated exercise may be as effective at reducing postprandial lipaemia.

These researchers find a scope for further research to determine if even shorter bouts of accumulated exercise (<10 minutes) confer a health benefit and whether an accumulated approach to physical activity increases adherence among the sedentary population at whom this pattern of exercise is targeted.

Reference:

Murphy MH et al; Sports Med. 2009;39(1):29-43. doi: 10.2165/00007256-200939010-00003.


Friday, June 5, 2009

Kinetic chain concepts in shoulder dysfunctions




Alterations in shoulder kinematics in shoulder impingement:
Ludewig et al investigated (humeral elevation in the scapular plane); glenohumeral and scapulothoracic kinematics and associated scapulothoracic muscle activity in a group of subjects with symptoms of shoulder impingement relative to a group of subjects without symptoms of shoulder impingement matched for occupational exposure to overhead work. Their work revealed:

1. In subjects of impingement there is:
i. decreased scapular upward rotation at the end of the 1st of the 3 phases,
ii. increased anterior tipping at the end of the third phase, and
iii. increased scapular medial rotation under the load conditions.

2. EMG pattern in impingement cases showed hyperactivity upper and lower trapezius in the final 2 phases, although the upper trapezius muscle changes were apparent only during the loaded condition. The serratus anterior muscle demonstrated decreased activity in the group with impingement across all loads and phases.

Comparison of scapular kinematics between elevation and lowering of the arm in the scapular plane (3):
Abnormal scapular kinematics have been identified in shoulder impingement patients during the concentric phase of arm elevation, and under static conditions. Borstad et al compared scapular orientation during both the concentric (elevation) and eccentric (lowering) phases of scapular plane abduction in subjects with and without shoulder impingement. This study found:

1. Differences in scapular tipping and internal rotation during the eccentric phase of arm elevation were identified at higher humeral angles in both affected & unaffected groups. However these findings are not found in the lower angles.

2. Symptomatic group demonstrated significant reductions in upward rotation at lower humeral elevation angles, and significant increases in anterior tipping at higher elevation angles as compared to the healthy group.

The finding of this confirms the recommendation made by Ludewig et al (4) in 1996. They suggested assessment of scapular tipping and internal rotation as well as upward rotation may be necessary to understand pathologies of the shoulder that are related to abnormal scapular kinematics.

Kinetic chain approach: One of the important non-traditional approaches evolving now a day in rehabilitation of shoulder dysfunction is Kinetic chain approach. The fundamental of this approach is “body does not operate in isolated segment” rather it is a dynamic functional synsitium.

The kinetic chain approach addresses gleno-humeral motion through scapular control & scapular control through trunk movement. The flow of activity in this pattern is from the proximal to distal direction.

Concepts of kinetic chain shoulder rehabilitation are as follows (McMullen J, 2000; Journal of athletic training):
1. For shoulder rehabilitation to be truly functional, the approach to the upper extremity should follow proximal to distal pathway along a kinetic chain.

2. Muscle around the shoulder function synergistically & should be integrated within the kinetic link system through out the rehabilitation.

3. Scapular control & coordinated rotator cuff activation are vital to successful shoulder rehabilitation & safe shoulder function.

4. Graded close kinetic chain exercises for the upper extremity must be scheduled in the initial phase of the shoulder rehabilitation.

Close kinetic approach:
Closed-chain exercise protocols are used extensively in rehabilitation of knee injuries and are increasingly used in rehabilitation of shoulder injuries. They are felt to be preferable to other exercise programs in that they simulate normal physiologic and biomechanical functions, create little shear stress across injured or healing joints, and reproduce proprioceptive stimuli. Because of these advantages, they may be used early in rehabilitation and have been integral parts of "accelerated" rehabilitation programs (6).

Specific exercises for scapular control:
In a controlled laboratory study Kibler et al studied restoration of control of dynamic scapular motion by specific activation of the serratus anterior and lower trapezius muscles which are supposed to be important part of functional rehabilitation.

Specific action of 2 dymanic exercises lawnmower and robbery are studied. These specific exercises activate key scapular-stabilizing muscles at amplitudes that are known to increase muscle strength. These exercises can be used as part of a comprehensive rehabilitation program for restoration of shoulder function. They activate the serratus anterior and lower trapezius-key muscles in dynamic shoulder control-while variably activating the upper trapezius.

However the study also recommended inferior glide and low row can be performed early in rehabilitation because of their limited range of motion, while lawnmower and robbery, which require larger movements, can be instituted later in the sequence.

References:

1. McMullenJ et al; J Athl Train. 2000 Jul;35(3):329-337.

2. Ludewig PM et al; Phys Ther. 2000 Mar;80(3):276-91.
3. Borstad JD et al; Clin Biomech (Bristol, Avon). 2002 Nov-Dec;17(9-10):650-9.
4. Ludewig PM et al; J Orthop Sports Phys Ther. 1996 Aug;24(2):57-65.

5. Kibler WB et al; Am J Sports Med. 2008 Sep;36(9):1789-98. Epub 2008 May 9.

6. Kibler WB et al; J Am Acad Orthop Surg. 2001 Nov-Dec;9(6):412-21.


Thursday, June 4, 2009

Thoracic, thoracolumbar junction & upper lumbar disc herniations- How they present to you?



Two level & multiple level thoracic disc herniation.

A. Boriani & colleagues reported a two-level thoracic disc herniation. According to the authors only 26 cases of dual disc herniations are reported before 1994. However, this case was a double, contiguous disc herniation in the thoracic spine (T7-T8, T8-T9) in a 44-year-old man. The findings are as follows:

1. Intermittent episodes of weakness and numbness in the lower extremities.
2. Paraesthesias radiating to the anterior and medial surfaces of the thigh and the leg (in this case parasthesia was mostly on the left side).
3. Mild sexual and urinary dysfunction.

B. Chen & colleagues reported a single case of acute noncontiguous multiple-level thoracic disc herniations with myelopathy. According to these authors multiple-level symptomatic disc herniations of the thoracic spine are rare, and the reported cases are mostly of contiguous, two-level lesions with chronic clinical presentation. Prior to 2004 no case of acute three-level noncontiguous ruptured thoracic disc herniations with myelopathy has been reported. This cases reported by them was of a 38-year-old man with a unique acute, triple-level, noncontiguous thoracic disc herniation (T6, T9-T10, and T11-T12). It presented as follows after minor trauma resulting from a motorcycle accident.

1. Delayed onset of lower limb weakness,
2. Paresthesias below the T10 dermatome.
3. Urinary dysfunction

The authors suggested further that thoracic disc herniation is variable and difficult to correlate with imaging findings, decompression at all lesion levels in a patient with symptomatic multiple-level ruptured thoracic disc herniations may be necessary to achieve complete symptom relief and satisfactory results.

Thoracolumbar junction disc herniations:

Thoracolumbar junction disc herniations show a variety of signs and symptoms because of the complexity of the upper and lower neurons of the spinal cord, cauda equina, and nerve roots. Furthermore, much is still unknown about thoracolumbar junction disc herniations because of their rare frequency. Tokuhashi & colleagues reviewed symptoms of thoracolumbar junction disc herniation to prepare a chart for the level diagnosis in the neurologic findings and symptoms.
Clinical features of 26 patients who later ware operated are as follows:

1. Patients with T10-T11 disc herniation showed moderate lower extremity weakness, increased patellar tendon reflex, and sensory disturbance of the entire lower extremities. (Common symptoms of 2 patients)

2. Patients with T11-T12 disc herniation experienced lower extremity weakness, and three patients had accentuated patellar tendon reflex. Sensory disturbance was observed in the anterolateral aspect of the thigh in one patient and on the entire leg in three patients. Bowel and bladder dysfunction was noted in three patients. (Common symptoms of 4 patients)

3. In the T12-L1 disc herniation group, muscle weakness and atrophy below the leg were advanced, and bowel and bladder dysfunction were also noted. Two of these three patients had bilateral drop foot, and one patient had unilateral drop foot; sensory disturbance was noted in the sole or foot and around the circumference of the anus, and the patellar tendon reflex and Achilles tendon reflex were absent. (Common symptoms of 3 patients)

4. Patients with L1-L2 disc herniation showed severe thigh pain and sensory disturbance at the anterior aspect or lateral aspect of the thigh. On the other hand, there were no clear signs of lower extremity weakness, muscle atrophy, deep tendon reflex, or bowel and bladder dysfunction in these patients. (Common symptoms of 6 patients)

5. In the L2-L3 disc herniation group, all patients had severe thigh pain and sensory disturbance of the anterior aspect or the lateral aspect of the thigh. Weakness in the quadriceps was noted in five patients and weakness in the tibialis anterior in two patients. Decreased or absence of patellar tendon reflex was observed in nine patients. Five patients had positive straight leg raising test results, and eight patients showed positive femoral nerve stretch test results. (Total 11 patients discussed)

Among thoracolumbar junction disc herniations, T10-T11 and T11-T12 disc herniations were considered upper neuron disorders, T12-L1 disc herniations were considered lower neuron disorders, L1-L2 disc herniations were considered mild disorders of the cauda equina and radiculopathy, and L2-L3 disc herniations were considered radiculopathy. These findings had relatively distinct differences among herniated disc levels.

Uniqueness of upper lumbar disc herniations:

Albert & colleagues considered L3-4 as a upper lumbar area. They reviewed 141 cases of upper lumbar disc herniations (L1-2, L2-3, L3-4). They found:

1. Pre-interventional signs and symptoms were highly variable.
2. Sensory, motor, and reflex testing was variable and potentially misleading in suggesting a level of herniation.

On analyzing radiographic studies (noncontrast CT, myelography, MRI) individually and operative findings as a standard for comparison, a high false-negative rate was found for all studies when considered individually, especially at the higher L2-3 level.

Uniqueness of upper lumbar spine disc herniations from surgical point:

Sanderson & colleagues considers upper lumbar disc herniations as unique especially from neurosurgical point of view. According to these authors herniated discs at the L1-L2 or L2-L3 level are different entities from those at lower levels of the lumbar spine.

The surgical outcome in terms of postoperative back and radicular pain is worse for herniated discs at L1-L2 and L2-L3 compared with those treated at L3-L4. Patients with L1-L2 or L2-L3 surgically treated herniated discs were more likely to have had previous lumbar surgery and required a fusion more often than their counterparts with L3-L4 herniated discs.

References:

1. Boriani S et al; Spine. 1994 Nov 1;19(21):2461-6.
2. Chen CF et al; Spine. 2004 Apr 15;29(8):E157-60.
3. Tokuhashi Y et al; Spine. 2001 Nov 15;26(22):E512-8.
4. Albert TJ et al; J Spinal Disord. 1993 Aug;6(4):351-9.
5. Sanderson SP et al; Neurosurgery. 2004 Aug;55(2):385-9; discussion 389.


Frozen shoulder- A mini review

Introduction:

Frozen shoulder or adhesive capsulitis describes the common shoulder condition characterized by painful and limited active and passive range of motion (1). Adhesive capsulitisis is controversial by definition and diagnostic criteria that are not sufficiently understood. Substantial disability and significant morbidity can result from shoulder disorders (2). Idiopathic adhesive capsulitis is a commonly recognized but poorly understood cause of a painful and stiff shoulder (3). According to prevalence reports (2), shoulder disorders have been reported to range from seven to 36% of the population (Lundberg 1969).

The clinical course of this condition is considered self-limiting and is divided into three clinical phases (6). Symptoms in adhesive capsulitis can last up to 2 years (5) and longer even up to 30 months (7). The diagnosis is primarily clinical and no significant changes are normally present at MRI or CT scan (7). Most treatments are conservative; however, indications for surgery do exist (5).

Etiological classification:

The etiology of frozen shoulder remains unclear; however, patients typically demonstrate a characteristic history, clinical presentation, and recovery. A classification schema is described, in which primary frozen shoulder and idiopathic adhesive capsulitis are considered identical and not associated with a systemic condition or history of injury. Secondary frozen shoulder is defined by 3 subcategories: systemic, extrinsic, and intrinsic.

Classification based severity of symptoms:

We also propose another classification system based on the patient's irritability level (low, moderate, and high), that we believe is helpful when making clinical decisions regarding rehabilitation intervention.

Interventions (Nonoperative) in frozen shoulder:

Levine & colleagues (4) found no significant difference for success of nonoperative treatment versus operative treatment or patient gender. Hence the topic of discussion mostly around the evidence successful modalities in frozen shoulder.

Kelley & colleagues have proposed a rehabilitation model based on evidence and intervention strategies matched with irritability levels.
1. Exercise and manual techniques are progressed as the patient's irritability reduces. Response to treatment is based on significant pain relief, improved satisfaction, and return of functional motion.
2. Patients who do not respond or worsen should be referred for an intra-articular corticosteroid injection.
3. Patients who have recalcitrant symptoms and disabling pain may respond to either standard or translational manipulation under anesthesia or arthroscopic release.

Hannafin & colleagues have discussed treatment modality “benign neglect” in frozen shoulder (8). While research reveals that there is no role of NSAIDs in management of adhesive capsulitis Dudkiewicz & colleagues have found, conservative treatment (physical therapy and NSAIDs) is a good long-term treatment regimen for idiopathic adhesive capsulitis (6).

However, common nonoperative interventions include patient education, modalities, stretching exercises, joint mobilization, and corticosteroid injections. Glenohumeral intra-articular corticosteroid injections, exercise, and joint mobilization all result in improved short- and long-term outcomes (1).

With supervised treatment, most patients with adhesive capsulitis experience resolution with nonoperative measures in a relatively short period. Only a small percentage of patients eventually require operative treatment (4).

Physiotherapy & corticosteroids are complimentary

There is strong evidence that glenohumeral intra-articular corticosteroid injections have a significantly greater 4- to 6-week beneficial effect compared to other forms of treatment (1). However, acording to Carette & colleagues reported a single intraarticular injection of corticosteroid administered under fluoroscopy combined with a simple home exercise program is effective in improving shoulder pain and disability in patients with adhesive capsulitis. Adding supervised physiotherapy provides faster improvement in shoulder range of motion. However their study revealed, when used alone, supervised physiotherapy is of limited efficacy in the management of adhesive capsulitis (9).

Out come of physiotherapy interventions for shoulder pain & stiffness:

Physiotherapy is often the first line of management for shoulder pain. Green & colleagues reviewed (CINAHL; 1996-2002) the efficacy of physiotherapy interventions for disorders resulting in pain, stiffness and/or disability of the shoulder. The diagnostic sub groups ware rotator cuff disease, adhesive capsulitis, anterior instability etc (2). However there is an existence of a clinical entity called mixed diagnosis; in which more than one clinical condition mentioned above are present. We have extracted the main points in the context of adhesive capsulitis:

1. There is no evidence that physiotherapy alone is of benefit for Adhesive Capsulitis
2. Laser therapy is said to demonstrate to be more effective than placebo for adhesive capsulitis.
3. There is no evidence of the effect of ultrasound in shoulder pain (mixed diagnosis), adhesive capsulitis or rotator cuff tendinitis.
4. When compared to exercises, ultrasound is of no additional benefit over and above exercise alone for shoulder pain.

Outcome of a stretching regimen in frozen shoulder:

Griggs & colleagues (3) examined the outcome of patients with idiopathic adhesive capsulitis who were treated with a stretching-exercise program.
Phase-II idiopathic adhesive capsulitis were treated with use of a specific four-direction shoulder-stretching exercise program and evaluated prospectively. The vast majority of patients who have phase-II idiopathic adhesive capsulitis are successfully treated with a specific four-direction shoulder-stretching exercise program. More aggressive treatment such as manipulation or capsular release was rarely necessary (3). In this study Griggs & colleagues have revealed that male gender and diabetes mellitus were associated with worse motion outcomes.

Patient satisfaction in physiotherapy treatment:

Griggs & colleagues (3) in their study have revealed: 90 % patients report of a satisfactory outcome with physiotherapy. 10 % are not satisfied with the outcome and 7 % requiring manipulation and/or arthroscopic capsular release. (* patients ware evaluated by Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire; and completion of the Short Form-36 (SF-36) Health Survey)

Reference:

1. Kelley MJ et al; J Orthop Sports Phys Ther. 2009 Feb;39(2):135-48.
2. Green S et al; Cochrane Database Syst Rev. 2003;(2):CD004258.
3. Griggs SM et al; J Bone Joint Surg Am. 2000 Oct;82-A(10):1398-407.
4. Levine WN et al; J Shoulder Elbow Surg. 2007 Sep-Oct;16(5):569-73. Epub 2007 May 24.
5. Tasto JP et al; Sports Med Arthrosc. 2007 Dec;15(4):216-21.
6. Dudkiewicz I et al; Isr Med Assoc J. 2004 Sep;6(9):524-6.
7. Brue S et al; Knee Surg Sports Traumatol Arthrosc. 2007 Aug;15(8):1048-54. Epub 2007 Feb 28.
8. Hannafin JA et al; Clin Orthop Relat Res. 2000 Mar;(372):95-109.
9. Carette S et al; Arthritis Rheum. 2003 Mar;48(3):829-38.


Wednesday, June 3, 2009

American College of Sports Medicine- position stand (year 2009) for progression models in resistance training for healthy adults.


Overload is a fundamental criterion for strength training. In order to stimulate further adaptation toward specific training goals, progressive resistance training (RT) protocols are necessary.

Fundamental principles:


The optimal characteristics of strength-specific programs include

1) Use of all verities of muscle contraction: Use of concentric (CON), eccentric (ECC), and isometric muscle actions.
2) Performance of bilateral and unilateral single- and multiple-joint exercises.
3) Sequential protocol: Strength programs sequence exercises to optimize the preservation of exercise intensity i.e.
a. Large before small muscle group exercises.
b. Multiple-joint exercises before single-joint exercises
c. Higher-intensity before lower-intensity exercises).

How the novices should go about their strength training:
Novice refers to untrained individuals with no RT experience or who have not trained for several years. For novice, training, it is recommended as follows:

1. Loads correspond to a repetition range of an 8-12 repetition maximum (RM).
2. Frequency should be 2-3 days a week.

How the intermediate & advanced should go about their strength training:
Intermediate refers to individuals with approximately 6 months of consistent RT experience. And advanced refers to individuals with years of RT experience. For Intermediate & advanced training, it is recommended as follows:

1. Individuals should use:

a. a wider loading range from 1 to 12 RM in a periodized fashion with emphasis on heavy loading (1-6 RM)
b. These high load exercises should use 3- to 5-min rest periods between sets.
c. These high load exercises should be performed at a moderate contraction velocity (1-2 s CON; 1-2 s ECC).

2. When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number.

3. Frequency should be 3-4 days a week for intermediate & 4-5 days a week for advanced training.

Hypertrophy training:
Similar program designs as said above are recommended for hypertrophy training with respect to exercise selection and frequency. In such cases
1. Loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion with emphasis on the 6-12 RM zone.
2. Rest between loadings: 1- to 2-min rest periods between sets at a moderate velocity.
Higher volume, multiple-set programs are recommended for maximizing hypertrophy.

Progression in power training entails two general loading strategies:
1) Strength training and
2) Use of light loads (0-60% of 1 RM for lower body exercises; 30-60% of 1 RM for upper body exercises) performed at a fast contraction velocity with 3-5 min of rest between sets for multiple sets per exercise (three to five sets).
It is also recommended that emphasis be placed on multiple-joint exercises especially those involving the total body.

Endurance training:
For local muscular endurance training, it is recommended that
1. Light to moderate loads (40-60% of 1 RM) be performed for high repetitions (>15) using short rest periods (<90 s)

Bottom line:

Recommendations should be applied in context and should be contingent upon an individual's target goals, physical capacity, and training status.

Reference:
American College of Sports Medicine; Med Sci Sports Exerc. 2009 Mar;41(3):687-708.

Tuesday, June 2, 2009

Exercise to counter smoking related oxidative stress

Oxidative stress because of smoking:

Both cigarette smoking and high fat meals induce oxidative stress, which is associated with the pathogenesis of numerous diseases (1, 2 , 3, 4 & 5).
Postprandial oxidative stress: Postprandial lipemia and oxidative stress provide more important information concerning susceptibility to disease, in particular cardiovascular disease (5).

Studies on oxidative stress by smoking

A. Bloomer & colleagues compared blood antioxidant status, oxidative stress biomarkers (xanthine oxidase, hydrogen peroxide, malondialdehyde) and TAG in 20 smokers and 20 non-smokers, matched for age and physical activity, in response to a high fat test meal standardized to body mass. Findings of this study indicate that young cigarette smokers experience an exaggerated oxidative stress response to feeding, as well as hypertriacylglycerolaemia, as compared with non-smokers. Hence it provides insight into another possible mechanism associating cigarette smoking with ill health and disease (1).

B. Cigarette smoking induces a significant oxidant effect related to variety of free radical-related diseases often affecting the upper respiratory tract, unless it is effectively compensated by the antioxidant barriers of the humans (2).
In the present study, the evaluation of the antioxidant compensatory mechanisms, by estimating the antioxidant capacity of extracellular defence (saliva and plasma) and the intracellular resistance of peripheral lymphocytes to oxidative stress in young healthy smokers, was investigated (2).
Study consisted of 20 young healthy male smokers and 20 age-matched non-smokers with similar dietary profiles were enrolled in the study (2).
Smokers exhibited higher plasma antioxidant capacity, but a significantly reduced ability of blood lymphocytes, to resist to hydrogen peroxide-induced DNA damage (2).

C. Cigarette smoke is a significant source of oxidative stress, one potential mechanism for its untoward health effects. The antioxidant defense system is partly comprised of antioxidant micronutrients, making it important to understand the relationship between cigarette smoking and circulating concentrations of antioxidant micronutrients (3).
Anti oxidants like ascorbic acid, alpha-carotene, beta-carotene, and cryptoxanthin.micronutrients are associated with health and longevity, this evidence documents yet another deleterious consequence of cigarette smoking on human health (3).
Compared with nonsmokers active smokers have greater than 25% lower circulating concentrations of ascorbic acid, alpha-carotene, beta-carotene, and cryptoxanthin. Concentrations of alpha-carotene, beta-carotene, and cryptoxanthin were 16-22% lower in former smokers compared with never smokers (3). Passive smokers i.e. low-dose exposures to tobacco smoke can result in lowered circulating antioxidant micronutrient concentrations (3).

D. Northrop-Clewes & colleagues studied the micronutrients; vitamins A, E, and C; the carotenoids; some of the B-vitamin group; and the minerals selenium, zinc, copper, and iron in smokers & non-smokers. The minerals examined in this study are to examine the effects on biochemical markers of mineral status which was attributed to inflammation (4).
1. Serum concentrations of selenium and erythrocyte GPx activity were lower in smokers. Erythrocyte CuZn-SOD activity and serum ceruloplasmin concentrations were elevated, while serum zinc concentrations were depressed only in heavy smokers.
2. Smoking appears to affect iron homeostasis mainly by changing hemoglobin concentrations, which were in general increased. Serum iron, TfR, and ferritin were mostly unaffected by smoking, except in pregnancy where there is evidence of increased erythropoiesis causing lower saturation of plasma transferrin and some evidence of lowering of iron stores.

The role of exercise in minimizing postprandial oxidative stress in cigarette smokers: “Exercise is medicine” the slogan sound apt!!!

Bloomer & colleagues (5) proposed exercise may aid in attenuating postprandial oxidative stress. They provided 3 different plausible mechanisms:

1. First, exercise stimulates an increase in endogenous antioxidant enzyme activity.
2. Second, exercise improves blood triglyceride clearance via a reduced chylomicron-triglyceride half-life and an enhanced lipoprotein lipase activity.
3. Third, exercise improves blood glucose clearance via an enhanced glucose transport protein translocation and protein content, as well as insulin-insulin receptor binding and postreceptor signaling.

Improvements in antioxidant status, as well as lipid and glucose processing, may aid greatly in minimizing feeding-induced oxidative stress in smokers. If so, and in accordance with the recent joint initiative of the American College of Sports Medicine and the American Medical Association, exercise may be viewed as a "medicine" for cigarette smokers at increased risk for postprandial oxidative stress.

References:
1. Bloomer RJ et al; Br J Nutr. 2008 May;99(5):1055-60. Epub 2007 Oct 10.
2. Charalabopoulos K et a;l; Int J Clin Pract. 2005 Jan;59(1):25-30.
3. Alberg A; Toxicology. 2002 Nov 15;180(2):121-37.
4. Northrop-Clewes CA et al; Clin Chim Acta. 2007 Feb;377(1-2):14-38. Epub 2006 Sep 1.
5. Bloomer RJ et al ; Nicotine Tob Res. 2009 Jan;11(1):3-11.

Eat wright, exercise adequately & of course DO NOT SMOKE

Dedicated to world anti-tobaco day


Monday, June 1, 2009

Motor control, Back pain & Transverse abdominis




Introduction:
Recently the focus has shifted to motor control than strength because “a strong muscle may lack a proper motor control over the joint it controls” (one may call it inability in strength). This might cause a array of dysfunction or painful disorders in a joint of it’s concern or may also be a cause for a disorder away from that place where the muscle does not exerts it’s works (Because of long kinetic chains i.e. effects of weakness in any part of the chain has a repercussion on other parts of the kinetic chain).

Many research articles off late on back pain focusing on muscle dysfunction in patients with low back pain have led to discoveries of impairments in deep muscles of the trunk and back. The muscle impairments are not those of strength but rather problems in motor control (1).

When it was found that it is not strength that has to be augmented rather a motor control has to be reinstituted; the approach of physiotherapy has also changed to “a motor learning exercise protocol” (1).

Hence to start rolling a rehabilitation protocol under such circumstances, the initial focus is on retraining the co-contraction of the deep muscles i.e. the transversus abdominis and lumbar multi-fidus (1).

In this review we will only discuss about transverse abdominis with both acute and chronic low back pain in terms of reducing the neuromuscular impairment and in control of pain.

Contribution of transverse abdominis:
There has been considerable interest in the literature regarding the function of transversus abdominis, the deepest of the abdominal muscles, and the clinical approach to training this muscle (3).

Anatomy of Transverse abdominis Muscle: this muscle spans dorso-ventrally. It originates on the internal surfaces of the 7th-12th costal cartilages, thoracolumbar fascia, iliac crest, and lateral third of the inguinal ligament, and it inserts (finishes) on the linea alba with the aponeurosis of the internal oblique, pubic crest, and pectin pubis via the conjoint tendon.

Exploring the kinetic chain connecting Shoulder & transverse abdominis:
For execution of shoulder functions require a stable spine. Research indicates that contribution from Tr. Abdominis is a key to stability of the spine during execution of functions involving shoulder.

Hodges & colleagues tried to explore
1. Chronological sequence of trunk muscle activity associated with arm movement &
2. To determine if dysfunction of this parameter (vide point no1) was present in patients with low back pain.

They found:
1. Movement in each direction resulted in contraction of trunk muscles before or shortly after the deltoid in control subjects.
2. The transversus abdominis was invariably the first muscle active and was not influenced by movement direction, supporting the hypothesized role of this muscle in spinal stiffness generation.
3. Contraction of transversus abdominis was significantly delayed in patients with low back pain with all movements.

This study by Hodges & colleagues also found an important thing i.e. there is a delayed onset of contraction of transversus abdominis indicates a deficit of motor control and is hypothesized to result in inefficient muscular stabilization of the spine further resulting in LBA syndromes.

The SI joint & transverse abdominis:
Epidemiological reviews of LBA have recently revealed that nearly 30% of all cases of LBA are due to SI joint dysfunction. Richardson & colleagues studied, role of transverse abdominis in relation to LBA due to sacroiliac joint laxity. They found:

1. The independent contraction of the transversus abdominis significantly decreases the laxity of the sacroiliac joint.
2. This decrease in laxity is larger than that caused by a bracing action using all the lateral abdominal muscles.
These findings are in line with the authors' biomechanical model predictions and support the use of independent transversus abdominis contractions for the treatment of low back pain.

Changes in postural control of transversus abdominis in LBA: Comparison of EMG of spinal muscles.
In another study involving EMG of Hodges & colleagues transversus abdominis, rectus abdominis, erector spinae, and oblique abdominal muscles found, the EMG onset of transversus abdominis was delayed in the LBP subjects with movement in each direction, while the EMG onsets of rectus abdominis, erector spinae, and oblique abdominal muscles were delayed with specific movement directions. The result of this study provides evidence of a change in the postural control of the trunk in people with LBP.

Does posture training help patients with LBA?
We have already discussed that Tr.Abdominis is intimately associated with lumboscaral stability & lack of which causes LBA from SI or lumbar region. We have also discussed that training of Tr.Abdominis leads to manage pain and dysfunction in this area. However postural advice forms a key component of physio’s advice in management of LBA. Then the next question is does posture training have impact on Tr. Abdominis?

To date, there have not been any investigations into the influence of lumbo-pelvic neutral posture on TrA activity. Reeve & colleagues studied whether posture influences TrA thickness which ultimately answers role of transversus abdominis (TrA) on spinal stability may be important in low back pain (LBP).

20 healthy adults were recruited and taught five postures:
(1) Supine lying;
(2) Erect sitting (lumbo-pelvic neutral);
(3) Slouched sitting;
(4) Erect standing (lumbo-pelvic neutral);
(5) Sway-back standing.

In each position, TrA thickness was measured (as an indirect measure of muscle activity) using ultrasound. Then a comparison was done in the thickness of Tr.Abdominis which shows the impact of posture on Tr.Abdominis. The findings are as follows:

1. Erect standing > sway-back standing
2. Erect sitting > slouched sitting

This study concluded, lumbo-pelvic neutral postures may have a positive influence on spinal stability compared to equivalent poor postures (slouched sitting and sway-back standing) through the recruitment of TrA. Therefore, posture may be important for rehabilitation in patients with LBP & spending time in training good posture is a worthwhile investment.

Reference (s):

1. Jull GA et al; J Manipulative Physiol Ther. 2000 Feb;23(2):115-7.
2. Hodges PW et al; Spine. 1996 Nov 15;21(22):2640-50.

3. Hodges PW; Man Ther. 1999 May;4(2):74-86.

4. Richardson CA et al; Spine. 2002 Feb 15;27(4):399-405.

5. Hodges PW et al; J Spinal Disord. 1998 Feb;11(1):46-56.
6. Reeve AMan Ther. 2009 May 12. [Epub ahead of print]