Monday, June 21, 2010

Lumbosacral weight bearing & impacts of lumbar/sacral anomalies




The sacrum weight transmission factors: The direction of the trabecular bone indicates the route of load transmission in the sacrum. From the various parts of the sacrum (body, facets, alae and laminae) distinct sets of trabeculae extend towards the auricular surface.

L5-S1 weight transmission

Weight transmitted from the fifth lumbar vertebrae to the sacrum is distributed in 3 separate components i.e.

(a) Anteriorly- through vertebral bodies
(b) Intermediately- through transverse elements
(c) Posteriorly- through lumbosacral facet joints

The posterior components of the fifth lumbar vertebra share greater proportion of load in comparison with the posterior elements of the upper lumbar vertebral levels.

The forces acting on the body and articular facets, at the upper end of the sacrum, are ultimately transmitted through the two auricular surfaces with an appreciable part of the load passing directly from the transverse process of the fifth lumbar vertebra to the ala of the sacrum through the lumbosacral ligament.

There are a few anatomical alterations pertaining to this area that alters the biomechanics of this area & weight transmission.

Anatomical alteration in sacrum & lumbosacral junctions:

1. Variable positions of scaral auricular surface & it’s varieties

According to a recent study by Mahato NK sacral auricular surface not only defines the magnitude of weight transmission to the hip bones but also the position of the auricular surfaces influence load bearing patterns at the sacrum.

The position of auricular surfaces may cause vertical shifts in weight-bearing patterns between the L-5 and S-1 segments, altering weight distribution at the lumbosacral and sacroiliac regions.
The auricular surfaces may be higher or lower than normal. Hence there are 3 varieties of auricular surfaces. The higher auricular surface occupied a high-up position (from upper S-1 to low S-2 segments) & lower auricular surface occupied a high-up position low-down auricular surface (from the low S-1 to low S-3 sacral segments). A normal position of the auricular surface is from the S-1 to the middle of the S-3 segments.

The position of the auricular surface varies in human sacra. These variations are associated with differential load bearing at the sacral joints. Only the high-up sacra demonstrated the presence of accessory articulating facets between L-5 and S-1. The position of the auricular surface can explain or possibly predict low-back pain situations.

a. Features of low-down sacra: The low-down sacra transmitted load predominantly via lower (S2-3) segments and exhibited stouter, broader, and efficient weight-bearing lower sacral elements, and a prominent gap between the S-1 segment and the rest of the sacrum. The low-down sacra are longer than they were broad, had a substantially broad body span at S-1, possess the smallest interauricular distance, and showed considerable depth of the plane of the facet joints.

b. Features of high-up sacra: They demonstrate unilateral or bilateral accessory articulating facets on the alae that articulates with extended transverse processes of the L-5 vertebrae. The high-up sacra:

1) are shorter and broader in comparison with the normal sacra
2) at times presented accessory articular facets on their alae
3) has a smaller body span and a wider ala
4) are found to have the plane of the facet joints nearer to the posterior aspect of the S-1 body
5) had the smallest of the facet areas.

2. Presence of rudimentary lumbosacral facet(s):

According to Pal et al, observations on the sacra with the anomalous articular processes provided strong evidence for the role of the neural arch elements in the load transmission. In specimens where the articular facet was absent on one or both sides, there was always an accessory facet on the ala of the sacrum so that the load was transmitted to this facet from the transverse process of the fifth lumbar vertebra.

In a recently published study by Mahato et al 16 out of 20 selected cases presented unilateral rudimentary facets, and the remaining four had facets that were bilaterally rudimentary facets. Rudimentary lumbosacral facet articulation(s) is found to affect load sharing at this region. This study also found:

a. Accessory articulating area: Rudimentary facet in sacrum is also show accessory articulating area on the upper surface of the ala on the same side as the rudimentary zygapophyseal facet. Sacrum with bilateral rudimentary facets demonstrates bilateral accessory L5-S1 articulations.

b. Strong ligamentous attachments: Strong ligamentous attachments between the L5 and S1 transverse elements on the sides of the rudimentary facets.

Development of strong L5-S1 lumbosacral ligamentous attachments or accessory articulations at the transverse elements serve a compensatory mechanism for load sharing at lumbosacral junctions bearing a rudimentary facet joint.

3. Sacralized fifth lumbar vertebrae:

Sacralizations represent a transitional state at lumbosacral junctions and are more susceptible to degenerative changes resulting from the altered load-bearing patterns at these regions.

Features of Sacra with fused L5:

a. Sacra with fused L5 possess significantly smaller heights than the normal ones if the fused L5 vertebra was excluded from the measurements.

b. On inclusion of the L5, these sacra presented
i. a grossly reduced distance between the zygapophyseal facets,
ii. a greater distance of the coronal plane of the facet joints from the posterior aspect of the L5,
iii. a narrower interauricular distance,
iv. slightly increased body width at the top of the sacrum (now L5),
v. a comparable auricular surface area (with inclusion of the fusion of L5 transverse process at the lateral mass) to the normal ones, attenuated facet area, and occasionally, small intervertebral space between L5 and S1.

c. The unilaterally fused variety exhibit overall smaller dimensions. None of these sacra show accessory articulations at their ala. The auricular surfaces in these sacra spanned from mid-L5 to mid-S2 segments. The fusion of L5 increased the sacral height, width, and auricular surface. The auricular surfaces appeared to be situated "low-down".

Sacralization of L5 vertebra entails morphological alterations in the sacrum. The remnants of the original sacra in these specimens presented grossly diminished parameters.

Sacralization of L5 possibly represents a structural and biomechanical adjustment to compensate for reduced joint interfaces associated with smaller sacra. It may correspond to one end of the transitional "spectrum," the other end being defined by lumbarization of the S1 sacral segment.

References:

1. Mahato NK; Clin Anat. 2010 Jun 8. (Association of rudimentary sacral zygapophyseal facets and accessory and ligamentous articulations: Implications for load transmission at the L5-S1 junction.)
2. Pal GP; J Anat. 1989 Feb;162:9-17.(Weight transmission through the sacrum in man.)
3. Mahato NK; Neurosurg Focus. 2010 Mar;28(3):E12. (Variable positions of the sacral auricular surface: classification and importance.)
4. Mahato NK; Spine J. 2010 May 21. [Epub ahead of print]. (Complete sacralization of L5 vertebrae: traits, dimensions, and load bearing in the involved sacra.)



Monday, June 14, 2010

Disease that mimic Ankylosing Spondylitis- DISH (Diffuse idiopathic skeletal hyperostosis)




I. Recent findings in DISH

The diagnosis of DISH or Forestier's disease is based solely on radiographic abnormalities defined using the Resnick criteria. DISH is a condition characterized by calcification and/or ossification of soft tissues, mainly entheses, ligaments and joint capsules. Its prevalence increases with age and, therefore, DISH is a relatively common entity in the elderly. Witnessing the present increase in lifespan, obesity, DM and metabolic syndrome in the Western population, the prevalence of DISH should be expected to rise.

Recent findings: Recent studies confirm that patients with DISH have

a. Strong association with obesity: DISH patients have a greater body mass index, increased waist circumference
b. Strong association with metabolic disturbances: DISH patients have disturbed lipid profile (dyslipidaemia), hypertension, , diabetes mellitus (DM), hyperuricaemia, metabolic syndrome and an increased risk for cardiovascular diseases.
c. In addition, DISH is most probably related to abnormal bone cell growth/activity reflecting the influence of metabolic factors that lead to new bone formation. Serum matrix Gla protein may be a marker of osteometabolic syndromes, such as DISH, that cause hyperostosis.

II. Extra-skeletal manifestation of DISH

The classical site of involvement is the spinal column with right anterolateral soft tissue ossification being the most characteristic feature. However, DISH is not limited to the spine, and may affect multiple peripheral sites independently. Extraspinal entheseal ossifications are common and observing their isolated presence may lead to the diagnosis of DISH. Furthermore, hypertrophic or atypical OA observed in joints usually not affected by primary OA has frequently been reported in DISH.

III. Following are few facts that is important for a clinician to know about DISH & AS:

1. a. Diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS) share involvement of the axial skeleton and peripheral entheses.
b. Both diseases produce bone proliferations in the later phases of their course. Patterns of these bone proliferations are dissimilar.
c. Both advanced DISH and advanced AS may cause the same limitations of spinal mobility and postural abnormalities.
c. However, the radiologic spinal findings are so different that changes due to each disease can be recognized even in patients in whom both diseases occur.

Radiologic differential diagnosis between the two diseases exists mostly as a consequence of a lack of awareness of their characteristic clinical and radiographic features.

Two characteristic radiographic features include:

a. The predominantly horizontal nature of the enthesiophyte in DISH.

b. Right preponderance in the thoracic region due to the presence of the thoracic aorta located in the left thoracic side.

The differentiating point radiologically is

A midthoracic notch in DISH which seemed to be confined to noninflammatory conditions, but was not found in ankylosing spondylitis.

2. Postural differentiation is also some times difficult between DISH & AS. In a study of 15 patients form the age of 51-91 years all seronegetive for HLA-B27 & diagnosed DISH showed that DISH can occasionally have severe limitations of spinal mobility, along with postural abnormalities that resemble long-standing advanced AS.

3. AS & DISH can occur in the same patient with their respective peculiar clinical & investigative feature. SI joint CT scan is an invaluable diagnostic aid in this case.
DISH is also found to co-exist with OA. But DISH differ from patients with primary OA in several aspects i.e. prevalence in the general population, gender distribution, anatomic site of primary involvement, magnitude and distribution in the spine and the peripheral joints.

IV. Options in management in DISH

Little is known about the pathogenesis of the disease and possible therapeutic interventions.

a. Treatment should be aimed at the symptomatic relief of pain and stiffness; the prevention, retardation or arrest of progression; the treatment of associated metabolic disorders and the prevention of spontaneous or induced complications.

b. Change of lifestyle, nutrition and therapeutic options to alleviate pain and stiffness are measures that might improve quality of life in patients affected by DISH. Control of associated metabolic disorders such as hypertension, hyperinsulinaemia with or without hyperglycaemia, hyperlipidaemia and hyperuricaemia may reduce the morbidities associated with these disorders and prevent further progression of the condition.

Chiropractic approach to management of DISH:

Though only one research mentioned 3 patients benefited a little out of 15 selected Troyanovich et al claimed in a case study that Chiropractic approach to management of DISH.

Following procedures are found to be effective in that case study- chiropractic manipulation and drop table adjustments, along with range-of-motion exercise, extension exercise, and standing lumbar extension traction.

Physiotherapeutic approach to management of DISH

According to Al-Herz et al who evaluated the effect of exercise therapy on back pain, spinal range of motion (ROM), and disability in persons with DISH exercise program designed for DISH led to small improvements in physical measures which achieved significance only for lumbosacral flexion. Out of only 16, 14 people completed this study 8 (53.3%) participants rated their status as improved, 3 (20%) as unchanged, and four (27%) were unsure about the benefit.

Exercise program included mobility, stretching, and strengthening exercises for the cervical, thoracic, and lumbar spine.

Final words:

Recent developments in our understanding of the molecular basis of the ligamentous and entheseal changes that lead to the development of DISH might pave the way to future, more targeted and effective therapies.

Readers are advised to refer my previous article on DISH on this blog

References:

1. Olivieri I et al; Curr Rheumatol Rep. 2009 Oct;11(5):321-8. (Diffuse idiopathic skeletal hyperostosis: differentiation from ankylosing spondylitis.)
2. Olivieri I et al; Rheumatology (Oxford). 2007 Nov;46(11):1709-11. Epub 2007 Oct 15. (Diffuse idiopathic skeletal hyperostosis may give the typical postural abnormalities of advanced ankylosing spondylitis.)
3. Maertens M et al; J Rheumatol. 1992 Dec;19(12):1978-83. (Simultaneous occurrence of diffuse idiopathic skeletal hyperostosis and ankylosing spondylitis in the same patient.)
4. Maertens M et al; Clin Rheumatol. 1992 Dec;11(4):551-7. (Evaluation of the involvement of axial entheses and sacroiliac joints in relation to diagnosis: comparison among diffuse idiopathic skeletal hyperostostis (DISH), osteoarthrosis and ankylosing spondylitis.)
5. Sarzi-Puttini P et al; Curr Opin Rheumatol. 2004 May;16(3):287-92. New developments in our understanding of DISH (diffuse idiopathic skeletal hyperostosis).
6. Mader R et al; Rheumatology (Oxford). 2009 Dec;48(12):1478-81. Epub 2009 Sep 25. (Extraspinal manifestations of diffuse idiopathic skeletal hyperostosis.)
7. Mader R; Expert Opin Pharmacother. 2005 Jul;6(8):1313-8. (Current therapeutic options in the management of diffuse idiopathic skeletal hyperostosis.)
8. Troyanovich SJ et al; J Manipulative Physiol Ther. 2003 Mar-Apr;26(3):202-6. (A structural chiropractic approach to the management of diffuse idiopathic skeletal hyperostosis.)
9. Al-Herz A et al; Clin Rheumatol. 2008 Feb;27(2):207-10. Epub 2007 Sep 21. (Exercise therapy for patients with diffuse idiopathic skeletal hyperostosis.)





Sunday, June 13, 2010

Scapular mobilization an effective manual therapy in painful limitations of shoulder



2 misconceptions about subacromial impingement & adhesive capsulitis

Subacromial impingement (SI) syndrome is a painful condition that occurs during overhead activities as the rotator cuff is compressed in the subacromial space. Unrecognized secondary causes of subacromial impingement may lead to treatment failure. Posterior capsular tightness, believed to alter glenohumeral joint kinematics, is often cited as a secondary cause of SI.

Karduna et al examined the effects of scapular orientation on clearance in the subacromial space in a cadaver study. Results from this study demonstrated no significant effect of posterior tilting and external rotation of the scapula but subacromial clearance was found to decrease with an increase in upward rotation, which is contrary to what was expected. These results suggest that changes in upward rotation observed in patients with impingement syndrome may serve to open the subacromial space.

In adhesive capsulitis there is tightening of posterior capsule. Poitras et al tried to test the conventional hypothesis that tightening of the posterior capsule would lead to increased subacromial pressure and increased superior translation during active abduction in the scapular plane. However contrary to their belief they found in their study tightening of the posterior capsule did not increase subacromial pressure, or increase superior or anterior translation during abduction in the scapular plane.

Scapular mobilization in shoulder painful limitations

Manual therapy is an important treatment in impingement syndrome: Senbursa et al compared the effectiveness of two physical therapy treatment approaches for impingement syndrome, either by joint and soft tissue mobilization techniques or by a self-training program. This study though a brief clinical trial showed patients treated with manual therapy combined with supervised exercise lead to improvement of symptoms including increasing strength, decreasing pain and improving function earlier than with exercise program only.

Scapular upward rotation is usually manifested in subacromial impingement cases or stiff shoulders secondary to subacromial impingement leading to adhesive capsulitis.

Surenkok et al evaluated the initial effects of scapular mobilization (SM) on shoulder range of motion (ROM), scapular upward rotation, pain, and function.

After SM, we found significant improvements for shoulder ROM, scapular upward rotation, and CSS (Constant shoulder score) between pretreatment and post-treatment compared with the sham and control groups. So this study found SM may be a useful manual therapy technique to apply to participants with a painful limitation of the shoulder. SM increases ROM and decreases pain intensity.

References:

1. Karduna AR et al; J Shoulder Elbow Surg. 2005 Jul-Aug; 14 (4):393-9. (Contact forces in the subacromial space: effects of scapular orientation.)
2. Poitras P et al; J Shoulder Elbow Surg. 2010 Apr; 19 (3):406-13. Epub 2009 Dec 11. (The effect of posterior capsular tightening on peak subacromial contact pressure during simulated active abduction in the scapular plane.)
3. Senbursa G et al; Knee Surg Sports Traumatol Arthrosc. 2007 Jul; 15 (7):915-21. Epub 2007 Feb 28. (Comparison of conservative treatment with and without manual physical therapy for patients with shoulder impingement syndrome: a prospective, randomized clinical trial.)
4. Surenkok O, et al; J Sport Rehabil. 2009 Nov; 18 (4):493-501. (Acute effects of scapular mobilization in shoulder dysfunction: a double-blind randomized placebo-controlled trial.)



Saturday, June 12, 2010

Importance of testing horizontal adduction & abduction in stiff shoulders

According to Lin et al in persons with stiff shoulder

a. A strong co-relationship is found between functional disabilities in a stiff shoulder and posterior shoulder tightness. The study also revealed significant relationship between functional disabilities and cross-chest adduction.

b. There exists a significant relationship between internal rotation and posterior shoulder tightness. Similarly there is also a significant relationship of external rotation and anterior shoulder tightness.

c. Further significant correlations between shoulder internal rotation and cross-chest adduction, shoulder external rotation and below-chest abduction are observed, indicating that internal and external rotations might be related to posterior and anterior shoulder stiffness.

d. Below-chest abduction and cross-chest adduction were found to provide reliable data in shoulder stiffness & disbility.

Reference:
Lin JJ et al; Man Ther. 2006 May;11(2):146-52. Epub 2005 Aug 10. (Reliability and validity of shoulder tightness measurement in patients with stiff shoulders.)

Isolated shoulder internal rotation restriction




Isolated shoulder internal rotation restrictions are rare clinical entities for physiotherapist to encounter in OPD set ups.
According to cyriax J in a pan-capsular involvement there is more external rotation restriction than abduction restriction than internal rotation. This restriction pattern is called capsular pattern. So only limitation of internal rotation is attributed to involvement of structures other than capsule i.e. muscles & IDK (labrum problems) etc.

A case in my clinic: A 42 year male reported with lateral arm pain. The patient has cervical spine involvement with Rt side rotation, side bend & back ward bending limited terminally but no ULTT tests ware positive. Both side levator scapulae ware tight.
First 10 sitting ware spend to improve ROM & myofascial work to improve length of elevators of scapula without much avail.

During the second 10 sitting it was found that shoulder IR/hand behind back is limited could reach maximum up to L3. No other shoulder tests are positive. No rotator cuff palpation is positive. During the resisted or active IR the pain was referred o the same spot of the lateral arm. This was little unusual for me. Resisted IR test refers to IDK of shoulder.

I found an opportunity to explore the possibility what is in the literature. So I searched PUBMED with key words (shoulder + Isolated + internal rotation + stiffness). I found 3relevant papers on this issue. Following is the summary

1. Laban et al have described “Occult periarthrosis of the shoulder”. According to this author shoulder internal rotation restriction may lead to complaints of lateral elbow pain similar to complaints of lateral epicondylitis. People from both sexes & age group from 33 to 87 yrs ware found to be affected in this study. The authors have suggested that occult shoulder periarthrosis is interlinked in a pathokinetic chain potentially predisposing to the presenting symptoms of tennis elbow.

2. Lin et al have found a significant relationship between internal rotation and posterior shoulder tightness.

3. Hung et al investigate differences in muscle stiffness between subjects with stiff shoulders and controls, and to determine the correlation between posterior shoulder muscle stiffness and ROM. This study found significant correlations were found between internal rotation and stiffness of 3 muscles i.e. posterior deltoid, infraspinatus, and teres minor. Among these 3 muscles, posterior deltoid muscle stiffness accounted for 51% of the variance in shoulder internal rotation beyond stiffness from the infraspinatus and teres minor muscles.

This study concluded that muscle stiffness is related to shoulder range of motion. It is important to consider the posterior deltoid, infraspinatus, and teres minor muscles in the rehabilitation of patients with restricted internal rotation of the shoulder.

References:
1. Laban MM; Am J Phys Med Rehabil. 2005 Nov;84(11):895-8. (Occult periarthrosis of the shoulder: a possible progenitor of tennis elbow.)
2. Lin JJ et al; Man Ther. 2006 May;11(2):146-52. Epub 2005 Aug 10. (Reliability and validity of shoulder tightness measurement in patients with stiff shoulders.)
3. Hung CJ et al; J Rehabil Med. 2010 Mar;42(3):216-20. (Relationships between posterior shoulder muscle stiffness and rotation in patients with stiff shoulder.)