Rotator cuff injury: still a clinical controversy?

Excerpt

The rotator cuff mechanism is the primary stabiliser of the gleno-humeral joint and is vulnerable to considerable morbidity because of its anatomy and function. Both intrinsic and extrinsic factors are responsible for rotator cuff pathology, which is a disease spectrum ranging from inflammation to full thickness tears. The most notable extrinsic factors are impingement and demographic variables, whereas age-related degeneration is the most important intrinsic factor. Failure of the rotator cuff may progress to involve the full thickness of the tendinous insertions of the supraspinatus and then may extend to involve the infraspinatus and subscapularis tendons. Tear size tends to increase with time because there is little potential for spontaneous healing. Thorough knowledge of the rotator cuff anatomy and the management of tendon failure at other sites are helpful in the approach to the management of rotator cuff tears. There is a remarkable inconsistency in perceptions among the orthopaedic surgeons about the indications for rotator cuff surgery. There is also no clear consensus in terms of the optimal management and the timing of surgical intervention of chronic degenerative rotator cuff lesions. The treating surgeon’s goal should be to identify the treatment most likely to relieve pain and restore the patient to the greatest durable function possible given the extent of the individual’s pathology. Decisions regarding the need for imaging should be based on whether the results are likely to affect treatment. Plain radiographs of the shoulder are helpful to assess the gleno-humeral articulation, the acromio-humeral distance and the acromion morphology. Ultrasonography (US), MRI and MRI-arthrography are all useful to evaluate the integrity of the rotator cuff tendons. Both MRI and US are highly accurate and sensitive (90% accuracy, 97% sensitivities), but have modest specificity (~67%) in diagnosing full-thickness and partial-thickness tears, when compared with the findings at arthroscopy [7]. However, MRI provides high-resolution, objective anatomic details of cuff tears and is also useful to evaluate the extent of de-lamination, muscle atrophy and extent of fatty infiltration. T2-weighted MRI images are moreover helpful to accurately estimate the cuff tear size. With better evaluation of the tear configuration, a more accurate impression of the reparability can be obtained. Severely retracted rotator cuff should be carefully interpreted as they may only represent the apex of a “U-shaped” tear, which is very amenable to a repair. High-resolution US in experienced hands can also give results equivalent to that of MRI, but its efficacy is operator- and interpreter-dependent, and inaccuracies in the evaluation have limited its use. …