Can imaging determine if a rotator cuff tear is traumatic?

AIM: We reviewed the last decade of literature to update a previous publication on this topic by the senior author. In New Zealand, traumatic causation has implications for entitlement for treatment though the Accident Compensation Corporation (ACC). Acuity and chronicity may also be relevant in determining repairability. METHODS: Literature was reviewed regarding acromial morphology, greater tuberosity (GT) cysts, acromiohumeral interval (AHI), fatty degeneration and atrophy, acromioclavicular (AC) arthrosis, tendinopathy, bursal changes and other features. RESULTS: Some factors can be considered normal for those middle aged and older, including AC arthrosis, type 1 and 2 acromion and tendinopathy. Some factors may indicate acuity, including haemorrhage and debris, GT oedema, mid-substance soft tissue tear, kinking of the tendon and isolated complete subscapularis tears. Other factors may be associated with chronicity, including significant fatty degeneration, positive tangent sign for atrophy, anterior GT cysts, type 3 acromion, critical shoulder angle (CSA) >35 degrees and acromial index (AI) <0.7. CONCLUSION: A multitude of factors on imaging may infer, to a varying degree, the likelihood of acuity or chronicity. The patient history is also of importance in determining causation.

The outcomes of shoulder arthroplasty in those aged ≥70 years with glenohumeral arthritis: a New Zealand Joint Registry study.

INTRODUCTION: Reverse total shoulder arthroplasty (RTSA) was traditionally reserved for the patient with rotator cuff tear arthropathy. As the indications for RTSA continue to expand, the role of RTSA in patients aged >70 years with glenohumeral arthritis and an intact rotator cuff remains unclear. AIM: To study the New Zealand Joint Registry (NZJR) and compare the outcomes of a primary Total Shoulder Arthroplasty (TSA), a primary RSA and an RSA performed for revision of a failed TSA in patients aged >70 years, to determine if there is clear evidence to support a primary RSA in those aged >70 years instead of a primary TSA METHOD: This is a retrospective study of the NZJR from 2000 to 2018. We included all primary TSAs, primary RTSAs, and those RTSAs that were performed for the revision of a failed TSA. We excluded those RTSAs that were performed for the revision of an RTSA or hemiarthroplasty. The primary outcome was the Oxford Shoulder Score (OSS) at 6 months and 5 years, with a secondary outcome being the subsequent revision rate. RESULTS: A total of 3449 primary TSAs, 4681 primary RTSAs, and 104 revision RTSAs were identified. The mean OSSs at 6 months for a primary TSA, a primary RTSA, and a revision RTSA were 39.5 ± 9.0, 35.5 ± 9.4, and 32.5 ± 9.7, respectively (P < .001, primary TSA vs. primary RSTA; P <.001, primary TSA vs. revision RTSA; P = .0252 primary RTSA vs. revision RTSA). The mean OSSs at 5 years for a primary TSA and a primary RTSA were 42.1 ± 7.5 vs. 39.8 ± 8.4, respectively (P < .001), with no results available for revision RTSA. The secondary outcome was the revision rate for those aged >70 years with osteoarthritis as their primary indication for surgery. The revision rates for a primary TSA and a primary RTSA were 0.53/100 component-years (95% confidence interval [CI] 0.38-0.72) and 0.51/100 component-years (95% CI 0.31-0.79), respectively (P = .193), which was not statistically significant. CONCLUSION: The TSA remains the gold standard for primary shoulder arthroplasty. For those individuals aged >70 years with osteoarthritis as their primary diagnosis, a primary TSA is associated with a higher OSS than and similar revision rates to a primary RTSA's. However, these patients must be counseled regarding the risk of subsequent cuff failure, as the outcomes from a revision RTSA are significantly inferior than those from a primary RTSA.

The reverse coracoacromial ligament transfer for "horizontal" acromioclavicular joint instability.

Background: Acromioclavicular (AC) horizontal instability is a problem affecting not only young athletic patients after a trauma to the AC joint but also older patients who have undergone distal clavicle resection. It may cause pain and poor functional outcomes unless the reconstruction technique specifically addresses the horizontal instability of the clavicle, in addition to the well-known superior instability. Methods: Three cadaveric specimens underwent dissection of the AC joint capsule to determine the superior attachments of the AC joint capsule. These shoulders subsequently underwent distal clavicle resection and were loaded to a 7-kg weight in the horizontal plane. The horizontal displacement of the clavicle was measured and resection continued to the point of horizontal instability of the clavicle. Thereafter, the reverse coracoacromial ligament reconstruction technique was performed and recreation of horizontal stability assessed. Utilization of the reverse coracoacromial ligament transfer in two clinical cases will also be presented. Results: The AC joint capsule is continuous with trapezius and deltoid insertions. The average distance between the articular surface and insertion of the capsule on the clavicle is 10 mm and on the acromion is 14.8 mm. Horizontal clavicular translation increased from 2.3 mm when intact to 3.3 mm with capsular transection, 8.7 mm with 5 mm clavicle resection, and finally 15 mm with a 10-mm clavicle resection. Horizontal instability of the clavicle was demonstrated with a 10-mm clavicle resection. Conclusion: Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm. A reverse coracoacromial ligament transfer may be a reasonable technique to address horizontal stability of the clavicle during AC joint reconstruction in the context of painful instability.

Epidemiology, Management, and Outcomes of Large and Small Native Joint Septic Arthritis in Adults.

BACKGROUND: Native joint septic arthritis (NJSA) is poorly studied. We describe the epidemiology, treatment, and outcomes of large joint NJSA (LNJSA) and small joint NJSA (SNJSA) in adults at Middlemore Hospital, Auckland, New Zealand. METHODS: This was a coding-based retrospective study of patients ≥16 years old admitted between 2009 and 2014. Prosthetic joint infections were excluded. RESULTS: Five hundred forty-three NJSA episodes were included (302 LNJSA, 250 SNJSA). Only 40% had positive synovial fluid culture. Compared to SNJSA, LNJSA has higher incidence (13 vs 8/100 000 person-years [PY]), occurs in older, more comorbid patients, and is associated with greater rates of treatment failure (23% vs 12%) and mortality, despite longer antibiotic treatment. Total incidence is higher than previously reported (21/100 000 PY), with marked interethnic variation. Incidence rises with age (LNJSA only) and socioeconomic deprivation (LNJSA and SNJSA). Tobacco smokers and males are overrepresented. The most commonly involved joints were knee (21%) and hand interphalangeal (20%). Staphylococcus aureus was the most common pathogen (53%). Mean antibiotic duration was 25 days for SNJSA and 40 days for LNJSA, and the mean number of surgical procedures was 1.5 and 1.6, respectively. Treatment failure was independently associated with LNJSA, age, intra-articular nonarthroplasty prosthesis, and number of surgical procedures. CONCLUSIONS: This is the largest contemporary series of adult NJSA. SNJSA has better outcomes than LNJSA and may be able to be safely treated with shorter antimicrobial courses. Incidence is high, with significant ethnic and socioeconomic variation. Microbiological NJSA case ascertainment underestimates case numbers as it frequently excludes SNJSA.