Outcomes after arthroscopic treatment for scaphoid nonunion using ipsilateral radius bone graft and a headless compression screw: a comparison between the patients with and without avascular necrosis.

PURPOSE: To determine whether avascular necrosis can affect clinical outcomes or the union incidence after arthroscopic bone grafting for the treatment of scaphoid nonunion. METHODS: This retrospective comparative study included thirty-four patients with scaphoid nonunion that underwent arthroscopic bone graft from the ipsilateral radius and internal fixation. The patients were divided into two cohorts (group A, with avascular necrosis, n = 15; group B, without avascular necrosis, n = 19) based on pre-operative magnetic resonance imaging findings. Additionally, the patients were grouped in accordance with the location of nonunion (waist, n = 27; proximal pole, n = 7). The mean follow-up was 20.7 months (range 12.0-40.0 months). Clinical outcomes, including the visual analog scale (VAS) pain score, grip strength, range of motion (ROM), Mayo Wrist Score (MWS), and Disabilities of the Arm, Shoulder, and Hand (DASH) score, were evaluated. Radiographic measurements for carpal bone alignment were assessed as well. RESULTS: Union rates did not differ between groups (group A, 93.3%; group B, 94.7%: p = 0.863), and the post-operative VAS pain score, ROM, and MWS were similar at follow-up for a minimum of one year. DASH and grip strength were significantly better in group B, but the intergroup differences were minimal (mean DASH 11.9 versus 9.6; mean grip strength 77.5% versus 95.4% of contralateral side). There was no significant intergroup difference in mean time to achieving union (group A, 14.9 weeks; group B, 14.6 weeks; p = 0.900). In post-operative radiographic assessments, no significant intergroup differences were noted in any of the parameters. Subgroup analysis regarding the location of nonunion showed there were no significant intergroup differences in union rates, mean time to achieving union, and clinical outcome measures at the last post-operative follow-up. CONCLUSIONS: Arthroscopic bone grafting and internal fixation in the treatment of scaphoid nonunion provided good union rates and satisfactory outcomes regardless of vascularity status.

Catastrophic failure of a titanium locking plate in a proximal humeral fracture: case report and literature review.

BACKGROUND: Angular stable locking plates have shown good clinical results in treating proximal humeral fractures, but complications are not uncommon. This study reported a rare case of catastrophic failure of a titanium locking plate. A retrieval analysis of the implants was performed using an optic microscope and a scanning electron microscope. CASE PRESENTATION: A 69-year-old male reported a right proximal humeral fracture at the surgical neck and was treated by open reduction and internal fixation with a locking plate system. Ninety-six days after surgery, the patient came to clinic for acute local pain over the shoulder without any trauma. The radiographs showed a complete breakage of the implant accompanying displaced fracture. Revision surgery was performed to restabilize the fracture with a longer locking plate. The follow-up radiographs at 9 months showed complete union of the bone fracture. CONCLUSIONS: From the retrieval analysis, repetitive torsion loads on the vulnerable area of the implant are assumed to cause this catastrophic event. It is recommended that adequate activity restriction, such as reaching, be undertaken to avoid this rare complication. Current study also provides contributive information for the modification of plate design and pre-operative planning for device configuration to improve the success rate of locking plate fixation.

Effect of radiocapitellar Achilles disc arthroplasty on coronoid and capitellar contact pressures after radial head excision.

BACKGROUND: Long-term radiographic arthritis has been commonly reported after radial head excision. Concern over radial head arthroplasty may arise in certain situations including capitellar arthritis, radiocapitellar malalignment, and in young and active patients. We hypothesized that radial head excision increases coronoid contact pressures, which may at least be partially reduced by radiocapitellar Achilles tendon disc arthroplasty. METHODS: Coronoid and capitellar contact pressure was measured on 6 human cadaveric elbows on a custom-designed gravity-valgus simulator under passive flexion from 0° to 90°. Sequential testing, starting with the intact specimen, resection of the radial head, and finally, radiocapitellar Achilles tendon disc arthroplasty were performed on each specimen. RESULTS: Mean contact pressure of the coronoid significantly increased after radial head excision (P < .0001) and significantly improved after Achilles disc arthroplasty (P < .0001). The pressure difference was most pronounced on the lateral coronoid. From 15° to 85° of elbow flexion, mean contact pressures on the lateral coronoid were 291 kPa and 476 kPa before and after radial head excision, respectively (P < .0001). Achilles disc arthroplasty significantly lowered coronoid contact pressures to 385 kPa (P = .002); however, they remained significantly higher than those in the intact radial head group (P = .0009). CONCLUSIONS: Radial head resection increases contact pressure in the coronoid, especially the lateral coronoid. This study showed that radiocapitellar Achilles disc arthroplasty significantly improves contact pressures on the coronoid after radial head resection. Achilles disc arthroplasty could be considered in patients who are not candidates for radial head arthroplasty.

Arthroscopic partial trapeziectomy and tendon interposition for thumb carpometacarpal arthritis.

BACKGROUND: The purpose of this study was to introduce arthroscopic partial trapeziectomy and tendon interposition for the treatment of symptomatic thumb carpometacarpal arthritis of Eaton stage II or III. METHODS: From August 2001 to April 2009, 23 patients with thumb carpometacarpal arthritis were treated using this technique. Pain score, range of motion, and pinch strength were clinically evaluated and compared with the preoperative values after a minimum follow-up duration of 24 months. RESULTS: Significant reduction in pain score and increases in range of motion and pinch strength were found (all p < 0.001) after a 2-year follow-up. The mean ± SD (median) postoperative pain score was 1.0 ± 0.7 (1.0) at rest and 1.3 ± 0.9 (1.0) during daily activities. The postoperative range of motion was 19.1° ± 4.2° (20°) for extension and 35.7° ± 7.1° (35.0°) for flexion, and the postoperative pinch strength was 86.5 % ± 19.9 % (90.0 %). No complications were observed in our patient series. CONCLUSIONS: Arthroscopic partial trapeziectomy and soft tissue interposition could be an alternative treatment method for patients with symptomatic thumb carpometacarpal arthritis of Eaton stage II or III.

Failure of the rotating-hinge knee megaprosthesis.

Recently, rotating hinge knee prostheses were applied more frequently due to improving modern implant designs. They are predominantly used in specific conditions with major bone defect or insufficiency of the collateral ligaments around the knee, often as salvage procedures. A case of rotating hinge knee megaprosthesis failure due to isolated tibial polyethylene stopper broken, which was never reported before, was investigated and treated in our institution. We suggested that rotating hinge knee prosthesis with incompetent medial collateral ligament is apt to failure due to the high valgus moment during gait. Sacrificing lateral collateral ligament or cutting the femur in slightly less than the normal 5° to 7° valgus may eliminate the risk of complication.