Critical shoulder angle is associated with full-thickness rotator cuff tears in patients with glenohumeral osteoarthritis.

BACKGROUND: Higher critical shoulder angle (CSA) is correlated with rotator cuff tears (RCTs), whereas lower CSA is associated with glenohumeral osteoarthritis (OA). Our goal was to investigate whether patients with concurrent glenohumeral OA and full-thickness RCTs demonstrate a higher CSA than patients with OA alone. METHODS: Using a 2-surgeon shoulder arthroplasty registry, we identified 31 patients with glenohumeral OA and full-thickness RCTs confirmed by plain radiography and magnetic resonance imaging, respectively. Sixty-two age- and gender-matched controls (1:2 ratio) with glenohumeral OA and an intact rotator cuff were identified from the same registry. Two independent observers evaluated the radiographs for CSA and acromiohumeral index. RESULTS: The average CSA was 30° in the OA control group and 35° in the concurrent RCT and OA group (P < .0001). Acromiohumeral index was comparable between the groups (P = .13). Interobserver reliability of the independent reviewers was excellent (κ = 0.89; Ρ = 0.95). The receiver operating characteristic curve for CSA demonstrated that a value >35° was 90% specific and 52% sensitive for a full-thickness RCT in the setting of OA (area under curve = 0.84). CONCLUSION: Concurrent glenohumeral OA and full-thickness RCT are associated with greater CSA values compared with patients with glenohumeral OA alone. The CSA measurement may be useful in determining the need for magnetic resonance imaging to assess rotator cuff integrity in the arthritic population.

Early Debris Formation with a Porous Tantalum Glenoid Component: Radiographic Analysis with 2-Year Minimum Follow-up.

BACKGROUND: Porous tantalum has been used effectively in hip, knee, and reverse shoulder arthroplasty implants. However, a first-generation porous tantalum glenoid component for use in anatomic shoulder arthroplasty previously demonstrated failure, with failure usually preceded by the appearance of intra-articular metallic debris. After redesign, the component was reintroduced in 2009. The purpose of the current study was to evaluate the radiographic and clinical outcomes of the redesigned glenoid component. METHODS: Sixty-eight patients undergoing total shoulder arthroplasty received a Trabecular Metal porous tantalum glenoid component (73 components; 5 patients underwent staged bilateral procedures). No polymethylmethacrylate cement was used (off-label usage in the U.S.). A grading system to assess metallic debris formation was developed using radiographs of the previous generation of porous tantalum glenoid components that failed. Radiographs from the current series were independently reviewed by 2 shoulder arthroplasty specialists, and their results were compared. Glenoid components were evaluated for signs of bone ingrowth and metallic debris formation. RESULTS: Sixty-six (90%) of the 73 components were evaluated at a minimum of 2 years of follow-up (mean radiographic follow-up of 50.8 months; range, 24 to 68 months). Of these, 92.4% demonstrated minimal or no glenoid radiolucency. Overall, the prevalence of metallic tantalum debris formation was 44% (29 of 66). Sequential radiograph review demonstrated that the incidence of metallic debris formation increased for each year of follow-up, with radiographs from 2, 3, 4, and ≥5 years of follow-up demonstrating a metallic debris incidence of 23%, 36%, 49%, and 52%, respectively. Additionally, the severity of metallic debris formation increased with follow-up duration. There was no component dissociation or revision due to implant breakage in this series. CONCLUSIONS: The porous tantalum glenoid component studied had excellent short-term component fixation. However, the development of metallic debris, increasing in both overall incidence and degree of severity over time, raises concern for potential failure of this glenoid component. Longer follow-up is required. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Nonunion of the clavicle treated with plate fixation: a review of forty-seven consecutive cases.

Forty-seven consecutive patients underwent superior plating for clavicular nonunion between 1995 and 2005. This retrospective analysis was performed to assess the efficacy of plate fixation and the need for iliac crest bone grafting. Forty-three patients were treated with pelvic reconstruction plates and four with straight dynamic compression plates. Of the patients, 30 were treated with local bone graft only, 14 with demineralized bone matrix, and 3 with distant autogenous bone graft. Of the fractures, 93% united after a single operation. Of the patients, 69% returned the Disabilities of the Arm, Shoulder and Hand questionnaire. The mean Disabilities of the Arm, Shoulder and Hand score was 14.6 (range, 0-53). Plate prominence or sensitivity resulted in removal in 20% of cases. We believe that superiorly applied plate fixation is effective for the treatment of clavicular nonunion. Distant autogenous bone graft is not necessary in most cases to obtain union.