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Reverse total shoulder arthroplasty was developed in the late 1980s for elderly patients with rotator cuff arthropathy. Several biomechanical advantages of the reverse shoulder arthroplasty result in improved deltoid function, which improves shoulder motion and function compared to other types of shoulder arthroplasty. The main indication for the reverse prosthesis is painful rotator cuff tear arthropathy. The indications for reverse shoulder arthroplasty have continued to expand since it was first performed in the United States in 2004. Although the results of reverse total shoulder arthroplasty have been generally favorable, the complication rate is higher than that of conventional total shoulder arthroplasty. Complications include those common to other shoulder procedures (infection, instability, and nerve injury) and those unique to reverse total shoulder arthroplasty (scapular notching, glenoid baseplate failure, component disassociation, and scapular stress fractures). It is helpful for orthopaedic surgeons to understand ways to avoid these complications and methods with which to treat them.

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We report a case of catastrophic failure of ceramic-on-ceramic total hip arthroplasty without precipitating event or trauma. The patient was a 64-year-old woman who had degenerative osteoarthritis and underwent the index primary total hip arthroplasty 3 years earlier. Intraoperative findings included an intact ceramic femoral head, a slightly damaged ceramic liner insert, diffuse metallosis, and excessive wear of the trunnion of the stem. After removal of the metallic debris, excision of metalloid tissue, and copious lavage of the joint, the prosthesis was revised to a modular revision system. Although previous operative reports had been reviewed before surgery, there was no indication of a head-neck taper mismatch. Only after revision surgery was performed, and high suspicion arose, were previous implant records analyzed and the mismatch identified.

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BACKGROUND: Although halo-vest immobilization remains a common form of treatment for type II odontoid fractures, nonunion and C1-2 instability may be the result in up to 20% to 40% of patients. PURPOSE: Supine and upright lateral X-ray films may allow early identification of patients likely to fail halo-vest treatment and earlier surgical treatment with decreased morbidity from prolonged unsuccessful halo-vest immobilization. STUDY DESIGN/SETTING: A prospective cohort study was performed. PATIENT SAMPLE: Twenty patients with type II odontoid fractures. OUTCOME MEASURES: Posttreatment nonunion and C1-2 instability as determined by plain X-ray films and computed tomography scan. METHODS: Both supine and upright lateral X-ray films were obtained immediately after halo-vest application and at the 2-week, 6-week, and 3-month follow-up. Flexion-extension lateral X-ray films were obtained after halo-vest removal. Patients with nonunion or instability underwent computed tomography scan. Upright X-ray films were compared serially to identify loss of reduction. Pairs of supine and upright X-ray films were compared to measure any change in displacement or angulation upon transition from supine to upright position. Nonunion patients were compared with healed patients to determine any difference in fracture behavior based on serial supine and upright X-ray films. RESULTS: Twenty patients with type II odontoid fractures were identified during the study period. Three patients with multiple trauma underwent immediate surgical stabilization. Three elderly patients with nondisplaced fractures were treated in a cervical orthosis. Fourteen patients initiated and completed 3 months of halo-vest immobilization. After halo-vest removal, 4 of 14 patients (29%) showed radiographic nonunion or instability. In all 4 nonunion patients, supine and upright radiographs at 2 weeks revealed change in fracture angulation > or =5 degrees between the supine and upright positions. In three of these patients standard serial upright lateral X-ray films failed to identify any loss of reduction. In the remaining patient, progressive angulation of 15 degrees was observed. No measurable change in angulation between supine and upright X-ray films was observed in any patient who healed successfully with halo-vest treatment. CONCLUSIONS: Obtaining both supine and upright lateral X-ray films during the follow-up period may identify patients at risk for failure of halo-vest treatment as early as 2 weeks after initiation of treatment. A change in fracture angulation > or =5 degrees suggests an increased risk of treatment failure and the potential benefit of early surgical stabilization.

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STUDY DESIGN: Retrospective review. OBJECTIVES: To determine whether radiographic measurements derived from standard computed tomography (CT) evaluation can be used to predict failure of nonoperative treatment in patients with unilateral facet fractures. SUMMARY OF BACKGROUND DATA: There is no consensus regarding treatment of unilateral cervical spine facet fractures. Management of this injury is based primarily on the presence of neurologic deficits and the degree of perceived spinal instability. CT-based criteria for predicting failure of nonoperative treatment in this patient population have not been examined. METHODS: Initial CT scans of all patients with unilateral cervical facet fractures were reviewed. Direct measurements included height and width of the facet fracture fragment, fracture displacement, and angulation. Calculated data included percent height and width of the fracture fragment based on the height and width of the contralateral intact facet. RESULTS: A total of 24 patients with 26 unilateral facet fractures were identified. Five patients with 5 facet fractures failed nonoperative management and required delayed surgical stabilization. Comparing patients successfully treated nonoperatively to those failing nonoperative management, a significant difference was found in absolute height of the fracture fragment (P = 0.0002), articular fracture height (P = 0.008), and height of the fracture fragment expressed as a percentage of the contralateral intact lateral mass (P = 0.026). CONCLUSION: The only significant risk factors identified for failure of nonoperative treatment were craniocaudal height of the fracture fragment and relative height of the fracture fragment expressed as a percentage of the intact lateral mass. This study suggests that patients with unilateral cervical facet fractures involving >40% of the absolute height of the intact lateral mass or an absolute height >1 cm are at increased risk for failure of nonoperative treatment. Failure of nonoperative treatment was not observed in any patient with a fracture involving less than 40% of the height of the lateral mass or an absolute height <1 cm.

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[structure: see text] Amino acid derivatives bearing an alkyne (AA-CCH) at either the N- or C-terminus readily react with W(CO)3(S2CNMe2)2 to replace the carbon monoxides and form the novel bis-alkyne complexes W(AA-CCH)2(S2CNMe2)2; the solution behavior of these complexes shows that only the alkyne, and not the other functional groups on the amino acid, bonds to the tungsten.

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