The understanding of the etiology of shoulder disorders in the sporting and occupational population, as well as age-related factors, has increased substantially over the past 30 years with advances in imaging and arthroscopic techniques. This special edition of Physical Therapy Reviews presents a synopsis of our current understanding of the etiology of selected shoulder conditions, psychometric properties of commonly used assessment procedures, and considerations for physiotherapeutic interventions.
A generation ago, the etiology of rotator cuff pathology was believed to originate mainly from the acromial or bursal side, with acromioplasties being indicated when conservative measures failed.Citation1 In contrast, internal impingement was proposed to explain lesions that became evident with the introduction of arthroscopy, where these lesions appeared to originate from the ventral surface of the rotator cuff.Citation2 The lesions are often found in combination with those of the labrum, such as superior labrum anterior-posterior (SLAP) lesions.Citation3 These aspects thus focus on the etiology of pain resulting from structures related directly to the glenohumeral joint. Wassinger and MyersCitation4 and Dickerson et al.Citation5 provide updates for possible mechanisms of injury during the baseball throw and work-related activities, respectively. The risk for internal impingement and SLAP lesions associated with posterior shoulder tightness in baseball players is outlined by Wassinger and Myers.Citation4 A useful summary of the throwing phases is presented, specifying from which phase injuries are likely to originate. The review by Dickerson et al.Citation5 indicates that specific recommendations to reduce occupational risk for shoulder injuries are lacking, and more work is needed to define these. Aspects to consider are working posture, maintaining the shoulder in more than 60° elevation, and fatigue. A clinical approach to assessment, management and prevention of occupational-related shoulder pain is outlined.Citation5
There has been recognition that more global factors can be contributing towards shoulder disorders. Patients presenting predominantly with shoulder pain may exhibit symptoms indicating different pathophysiological mechanisms. Various classifications of these exist, such as nociceptive pain, peripheral neuropathic pain and central sensitisation. Moloney et al.Citation6 provide a review of the evidence for these mechanisms for patient presenting with non-specific arm pain. It is often seen in clinical practice that patients present with symptom patterns indicating central sensitization, in addition to more defined nociceptive pain. This is likely to be more evident in patients with adhesive capsulitis or occupational-related arm pain, but also occurs in patients with rotator cuff pathology.
Various clinical assessment procedures have been described for the shoulder. The utility of orthopaedic tests for labralCitation7 and rotator cuff injuriesCitation8 has recently received attention elsewhere. In this edition, RoyCitation9 provides an overview of the psychometric properties of physical examination procedures commonly used by physical therapists. The proposed contribution of posterior shoulder structures towards internal impingement and labral lesions threads across a number of the reviews in this edition. Salamh et al.Citation10 present various measurements to assess the flexibility of these structures.
Clinically, emphasis has been placed on the assessment of scapular dysfunction as a contributing factor for the etiology of shoulder pathology or pain, and also as a consequence of these. LucadoCitation11 summarises the current evidence for changes in electromyographic (EMG) activity of scapular muscles in patient with shoulder impingement, labral lesions or multi-directional instability. At this stage, the evidence is not consistent and decisions for appropriate management still rely predominantly on clinical observation and assessment
A comprehensive synopsis of current understanding of pathologies of the rotator cuff and biceps is provided by Lorenz et al.Citation12 Various treatment, methods are discussed, including acupuncture, electrotherapy, manual therapy and exercise. Pabian et al.Citation13 discuss advances of various surgical techniques for rotator cuff tears, providing guidelines for post-operative rehabilitation. The review is carefully supported by evidence from studies investigating EMG activity of the rotator cuff during specific exercises. Only minimal or no activity of the rotator cuff muscles should be allowed in the first phase of the maximum protection or passive exercises. This is progressed throughout the second (moderate protection and active) and third (minimum protection and resistive) phases.
Debate is needed to progress our understanding of all aspects of prevention, assessment and management of shoulder disorders. LewisCitation14 eloquently challenges current concepts for the development of rotator cuff injuries and shoulder pain. His theories are well grounded on scientific studies and he offers alternatives for treatment. Finally, Sueki and ChaconasCitation15 discuss the concept of regional interdependence as it related to applying mobilization techniques for the thoracic spine among the population with shoulder disorders. Management of shoulder pain has thus progressed from addressing single structures, such as the supraspinatus tendon with cross-frictions,Citation16 to a multi-structural approach, considering not only potential sources of symptoms but all possible contributing factors towards the etiology or injuries, maintenance of symptoms, and recurrence.
In conclusion, we would like to thank the authors and reviewers for contributing their time and expertise toward this special issue. We would also like to recognize the editorial staff for their work and support in developing this issue. Last but not least, we would like to thank Professor David Baxter for entertaining the idea of a special shoulder issue.
Gisela Sole
School of Physiotherapy
University of Otago
Dunedin, New Zealand
Morey J. Kolber
Department of Physical Therapy
Nova Southeastern University
Fort Lauderdale, Florida, USA
References
- Neer CS. Anterior acromioplasty for the chronic impingement syndrome in the shoulder: a preliminary report. J Bone Joint Surg Am. 1972;54:41–50.
- Paley KJ, Jobe FW, Pink MM, Kvitne RS, ElAttrache NS. Arthroscopic findings in the overhand throwing athlete: evidence for posterior internal impingement of the rotator cuff. Arthroscopy. 2000;16:35–40.
- Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics. Arthroscopy. 2003;19:404–20.
- Wassinger CA, Myers JB. Reported mechanisms of shoulder injury during the baseball throw. Phys Ther Rev. 2011;16:305–9.
- Dickerson CR, Brookham RL, Chopp JN. The working shoulder: assessing demans, identifying risks, and promoting healthy occupational performance. Phys Ther Rev. 2011; 16:310–20.
- Moloney N, Hall T, Doody C. Pathophysiological mechanisms in non-specific arm pain. Phys Ther Rev. 2011;16:321–30.
- Meserve BB, Cleland JA, Boucher TR. A meta-analysis examining clinical test utility for assessing superior labral anterior posterior lesions.Am J Sports. Med. 2009;37(11):2252–8.
- Hughes PC, Taylor NF, Green RA. Most clinical tests cannot accurately diagnose rotator cuff pathology: a systematic review. Aust J Physiother. 2008;54:159–70.
- Roy JS, Esculier J-F. Psychometric evidence for clinical outcome measures assessing shoulder disorders. Phys Ther Rev. 2011;16:331–46.
- Salamh PA, Corrao M, Hanney WJ, Kolber MJ. The reliability and validity of measurements designed to quantify posterior shoulder tightness. Phys Ther Rev. 2011;16:347–55.
- Lucado AM. Scapular muscle imbalance: implications for shoulder pain and pathology. Phys Ther Rev. 2011;16:356–64.
- Lorenz D, Walker JC, Burke D. Shoulder tendinopathy. Phys Ther Rev. 2011;16:365–73.
- Pabian P, Rothschild C, Schwartzberg R. Rotator cuff repair: considerations of tear types, surgical characteristics, and evidence-based rehabilitation. Phys Ther Rev.2011;16:374–87.
- Lewis J. Subacromial impingement syndrome: a musculoskeletal condition or a clinical illusion? Phys Ther Rev.2011;16:388–98.
- Sueki DG, Chaconas EJ. The effect of thoracic manipulation on shoulder pain: a regional interdependence model. Phys Ther Rev. 2011;16:399–408.
- Cyriax J, Textbook of orthopaedic medicine - diagnosis of soft tissue lesions, 8th ed., London: Bailliere and Tindall; 1982.