Shang-Wen Tsai1, Chien-Fu Jeff Lin2, Yun-Hsuan Tzeng3, Chun-Cheng Lin1, Ching-Kuei Huang1, Ming-Chau Chang1, Chao-Ching Chiang4. 1. Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC. 2. Department of Statistics, National Taipei University, Taipei, Taiwan, ROC; Department of Orthopedic Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan, ROC. 3. Division of Medical Imaging for Health Management, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC. 4. Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC. Electronic address: 1966chiang@gmail.com.
Abstract
BACKGROUND: Cut-out failure is one of the most common complications in the Gamma3 nail fixation system. The purpose of this retrospective study was to determine pre-operative or intra-operative risk factors for cut-out failure of lag screws in unstable, intertrochanteric fractures fixed with short Gamma3 nails. METHODS: One hundred and seventy-six patients over 60 years of age, with unstable intertrochanteric fractures (AO/OTA 31-A2, 31-A3) treated with short Gamma3 nails were included in this study. All patients completed a minimum of 1-year follow-up. Analysis of post-operative radiographs included assessment for cut-out failure of lag screw, appropriateness of the entry point, posterior lag screw axis, fracture gaps, posterior displacement of the proximal fragment, and tip-apex distance. RESULTS: Of the 176 patients in this study, 22 patients were identified with cut-out failure. Multivariate logistic regression analysis revealed that improper entry point in an antero-posterior projection (odds ratio 10.39, 95% confidence interval 1.74-78.4), posterior displacement distance of the proximal fragment in a lateral projection (odds ratio 1.35, 95% confidence interval 1.17-1.59), and female sex (odds ratio 17.14, 95% confidence interval 1.88-876.11) were correlated with cut-out failure. CONCLUSION: This study emphasizes the importance of an optimal position of reduction in the lateral projection in reducing the risk of cut-out failure. In addition, sex difference in bone mineral density, proximal femur geometry, and the bone strength in elderly females may explain why female sex is a risk factor.
BACKGROUND: Cut-out failure is one of the most common complications in the Gamma3 nail fixation system. The purpose of this retrospective study was to determine pre-operative or intra-operative risk factors for cut-out failure of lag screws in unstable, intertrochanteric fractures fixed with short Gamma3 nails. METHODS: One hundred and seventy-six patients over 60 years of age, with unstable intertrochanteric fractures (AO/OTA 31-A2, 31-A3) treated with short Gamma3 nails were included in this study. All patients completed a minimum of 1-year follow-up. Analysis of post-operative radiographs included assessment for cut-out failure of lag screw, appropriateness of the entry point, posterior lag screw axis, fracture gaps, posterior displacement of the proximal fragment, and tip-apex distance. RESULTS: Of the 176 patients in this study, 22 patients were identified with cut-out failure. Multivariate logistic regression analysis revealed that improper entry point in an antero-posterior projection (odds ratio 10.39, 95% confidence interval 1.74-78.4), posterior displacement distance of the proximal fragment in a lateral projection (odds ratio 1.35, 95% confidence interval 1.17-1.59), and female sex (odds ratio 17.14, 95% confidence interval 1.88-876.11) were correlated with cut-out failure. CONCLUSION: This study emphasizes the importance of an optimal position of reduction in the lateral projection in reducing the risk of cut-out failure. In addition, sex difference in bone mineral density, proximal femur geometry, and the bone strength in elderly females may explain why female sex is a risk factor.
Authors: L Henry Goodnough; Harsh Wadhwa; Seth S Tigchelaar; Malcolm R DeBaun; Michael J Chen; Matt L Graves; Michael J Gardner Journal: Arch Orthop Trauma Surg Date: 2021-04-07 Impact factor: 2.928