Correlation of magnetic resonance and arthroscopy in the diagnosis of shoulder injury.

BACKGROUND: Advances in shoulder magnetic resonance imaging (MRI) and arthrography (MRA) have revolutionised musculoskeletal diagnosis and surgical planning. Despite this, the overall accuracy of MRI, with or without intra-articular contrast, can be variable. METHODS: In this prospective non-randomised analysis, 200 participants (74.5% males) with suspected shoulder injuries underwent MRI (41.0%) or MRA followed by arthroscopy. A study specific proforma was developed to ensure consistency of reporting by radiologists and surgeons. The reports were compared to assess the predictive power of MRI/MRA. Specific assessment of rotator cuff tendon appearance, long head of biceps (LHB) tendon appearance, position and anchor, subacromial space, glenoid labrum and humeral cartilage grade were included. RESULTS: Shoulder MRA demonstrated a higher agreement with arthroscopy than MRI for supraspinatus, infraspinatus and subscapularis tendon appearance (κ = 0.77 vs. κ = 0.61, κ = 0.55 vs. κ = 0.53 and κ = 0.58 vs. κ = 0.46 respectively). There were also superior agreement rates with MRA compared to MRI for LHB tendon appearance (κ = 0.70 vs. κ =0.54) and position (κ = 0.89 vs. κ = 0.72). As an overall assessor of shoulder pathology we found significantly higher total agreement scores when MRA was used (p = 0.002). DISCUSSION: Whilst magnetic resonance imaging with arthrography is an extremely useful tool to assess underlying pathological shoulder states it does not confer 100% accuracy. In cases whereby this modality is inconclusive, an examination under anaesthesia and diagnostic arthroscopic assessment for the detection of intra-articular shoulder pathology may be considered.

Medium to long-term results of a recessed glenoid for glenoid resurfacing in total shoulder arthroplasty.

BACKGROUND: Recessed mini-glenoid components provide an alternative to total shoulder replacement that may avoid some of the known shortcomings and complications associated with shoulder hemiarthroplasty or standard glenoid components in difficult cases. This study reports survivorship, radiological and clinical outcomes of a recessed mini-glenoid implant in a consecutive cohort. METHODS: Retrospective cohort study reporting outcomes of 28 consecutive shoulders (27 patients) following total shoulder replacement using a recessed, cemented mini-glenoid implant at two sites. RESULTS: The most frequent diagnosis was primary osteoarthritis (79%); glenoid morphology was Walch Type A (67%), B1 15%, B2 10% and C 10%. At final follow-up, pain was 16.3 (SD = 23.1), American Shoulder and Elbow Score was 64.5 (SD = 31.9) and (normalized) Constant score was 83.0 (SD = 20.7). Implant survivorship at average final follow-up of seven years (3-13) was 96.4%. Seven mini-glenoids showed small peripheral radiolucent lines at one-year X-ray follow-up but were non-progressive on subsequent imaging. DISCUSSION: Recessed polyethylene mini-glenoid is an attractive alternative for shoulder arthroplasty and provides an intermediate solution between standard glenoid components and hemiarthroplasty. Our medium to long-term results demonstrate reliable clinical outcomes, absence of glenoid erosion, low complication rate and satisfactory implant survivorship.