Ji Wan Kim1, Derly O Cuellar2, Jiandong Hao3, Benoit Herbert3, Cyril Mauffrey4. 1. Department of Orthopaedic Surgery, Haeundae Paik Hospital, Inje University, College of Medicine, 1435, Jwa-dong, Haeundae-gu, Busan, 612-862, Republic of Korea. 2. Department of Orthopaedic Surgery, Saint Louis University School of Medicine, 3635 Vista at Grand Blvd., St. Louis, MO, 63104, USA. 3. Department of Orthopaedics, Denver Health Medical Center, University of Colorado, School of Medicine, 777 Bannock Street, Denver, CO, 80204, USA. 4. Department of Orthopaedics, Denver Health Medical Center, University of Colorado, School of Medicine, 777 Bannock Street, Denver, CO, 80204, USA. Cyril.mauffrey@dhha.org.
Abstract
PURPOSE: The purpose of this study was to identify the underlying cause by simulating the forces involved in a controlled laboratory setting, and then to illustrate some intraoperative tips on how to detect this malalignment and suggest solutions prevent this intraoperative complication. METHODS: The Expert Asian Femoral Nail (A2FN) and Proximal Femoral Nail Antirotation (PFNA) reconstruction nail systems were evaluated to compare the characteristics of each nailing system and their reactions to soft tissue tension at the time of proximal reconstruction screw placement. Soft tissue tension was simulated by placing a fulcrum under the distal drill sleeve and exerting a load on the targeting device via the addition of weights. The occurrence and degree of guide malalignment were determined while gradually increasing the weight. RESULTS: When soft tissue tension was simulated on the drill/guide sleeve of the A2FN, the drill sleeve deviated from the proximal screw hole proportionally to the weight applied and the K-wire guide passed outside of the nail at a weight of 7 kg. However, the drill sleeve of the PFNA was aligned exactly to the center of nail axis and the K-wire passed cleanly through the proximal locking hole regardless of weight applied. CONCLUSIONS: Inaccurate guidance of the screw-targeting device can be caused by soft tissue tension. Thus, the authors recommend that careful attention be placed on minimizing soft tissue tension during proximal screw placement while using the targeting device of the A2FN system.
PURPOSE: The purpose of this study was to identify the underlying cause by simulating the forces involved in a controlled laboratory setting, and then to illustrate some intraoperative tips on how to detect this malalignment and suggest solutions prevent this intraoperative complication. METHODS: The Expert Asian Femoral Nail (A2FN) and Proximal Femoral Nail Antirotation (PFNA) reconstruction nail systems were evaluated to compare the characteristics of each nailing system and their reactions to soft tissue tension at the time of proximal reconstruction screw placement. Soft tissue tension was simulated by placing a fulcrum under the distal drill sleeve and exerting a load on the targeting device via the addition of weights. The occurrence and degree of guide malalignment were determined while gradually increasing the weight. RESULTS: When soft tissue tension was simulated on the drill/guide sleeve of the A2FN, the drill sleeve deviated from the proximal screw hole proportionally to the weight applied and the K-wire guide passed outside of the nail at a weight of 7 kg. However, the drill sleeve of the PFNA was aligned exactly to the center of nail axis and the K-wire passed cleanly through the proximal locking hole regardless of weight applied. CONCLUSIONS: Inaccurate guidance of the screw-targeting device can be caused by soft tissue tension. Thus, the authors recommend that careful attention be placed on minimizing soft tissue tension during proximal screw placement while using the targeting device of the A2FN system.
Authors: Christophe Sadowski; Anne Lübbeke; Marc Saudan; Nicolas Riand; Richard Stern; Pierre Hoffmeyer Journal: J Bone Joint Surg Am Date: 2002-03 Impact factor: 5.284
Authors: Alan Afsari; Frank Liporace; Eric Lindvall; Anthony Infante; Henry C Sagi; George J Haidukewych Journal: J Bone Joint Surg Am Date: 2010-09 Impact factor: 5.284