Incidence and Risk Factors for Implant Failure in Spinal Metastasis Surgery.

STUDY DESIGN: Retrospective study. PURPOSE: To investigate the incidence of symptomatic and asymptomatic implant failure in spinal metastasis surgery and identify potential risk factors. OVERVIEW OF LITERATURE: Surgical stabilization with instrumentation is an established method for the treatment of spinal metastasis. However, very few studies have investigated the incidence and risk factors for implant failure after spinal instrumentation surgery for the treatment of spinal metastasis. METHODS: This study recruited 88 patients who received surgical stabilization with instrumentation for the treatment of spinal metastasis. Their medical records and postoperative X-rays were reviewed for evidence of implant failure. Statistical analysis with logistic regression was performed to assess nine potential risk factors for the development of implant failure, including patient's age at operation, gender, survival, primary tumor, spinal level involved, construct length, decompression levels, fusion material utilization, and radiotherapy application either before or after surgery, to identify potential contributing risk factors. RESULTS: Implant failure was identified in nine out of 88 cases (10.2%) with two cases requiring implant removal: one case included a progressive kyphosis that resulted in nonhealing sore and the other involved a deep-seated wound infection that spread to the implants. Another case required wound debridement due to superficial wound infection. The remaining six cases were asymptomatic, despite postoperative X-rays demonstrating evidence of implant failure. No patient required implant revision. Logistic regression analysis demonstrated that patients who received radiotherapy either before or after surgery were less likely to develop implant failure. CONCLUSIONS: The development of radiological implant failure following surgical treatment of spinal metastasis is common. However, symptomatic implant failure leading to revision surgery is uncommon. Our findings suggest that radiotherapy, either before or after spinal surgery, is not associated with the development of implant failure.

Arthroscopic Thermal Shrinkage: A Novel Method for the Treatment of Chronic Volar Plate Instability at the Metacarpal Phalangeal Joint of the Thumb.

Background: Chronic volar plate instability of the thumb metacarpal phalangeal joint (MCPJ) is a disabling clinical problem. Patients usually present with pain and disability in terms of reduction in pinch and grip power. Numerous surgical techniques have been described for the treatment of this condition. Here we describe a novel method for the treatment of this condition by thermal shrinkage of the volar plate via thumb MCPJ arthroscopy. Methods: A retrospective review of 8 patients with chronic thumb MCPJ volar plate instability treated with the novel technique of thermal shrinkage of the volar plate via thumb MCPJ arthroscopy. The primary outcome is maintenance of saggital plane stability at the thumb MCPJ. Secondary outcomes include pinch and grip power, The Disabilities of the Arm, Shoulder and Hand (DASH) Score and thumb MCPJ range of movement. The duration of follow up and complications were also reviewed. Results: The mean follow up period was 41.4 months (range, 2-134 months). One case had recurrence of instability requiring open volar plate capsulodesis. All other cases had their thumb hyperextensibility resolved and maintained throughout the entire follow up period, up to 134 months for the case with the longest duration of follow up. Conclusions: Preliminary results suggest this novel, minimally invasive technique for the treatment of thumb MCPJ volar plate instability is effective and the long term follow up results are durable.

Malignant schwannoma of the radial nerve with unusual presentation: a case report.

Malignant schwannoma (MPNST) is a rare tumor. Many of these cases occur in patients with neurofibromatosis type I (NF-1) and they usually present as a mass lesion which rapidly increase in size with or without neurological symptoms. Here we present an unusual case of MPNST along the radial nerve in which the patient has no underlying neurofibromatosis type I.