Joshua A Parry1, Travis Sapp2, Joshua R Langford3, Kenneth J Koval4, George J Haidukewych3. 1. Department of Orthopaedics, Denver Health, University of Colorado School of Medicine, Denver, CO. 2. Department of Orthopaedics, Florida State College of Medicine, Orlando, FL. 3. Department of Orthopaedics, Orlando Health, Orlando, FL; and. 4. Department of Orthopaedics, Memorial Hospital, Gulfport, MS.
Abstract
OBJECTIVES: To evaluate variables associated with lag screw sliding after single-screw cephalomedullary nail (CMN) fixation of intertrochanteric femur fractures. DESIGN: Retrospective cohort study. SETTING: Level-one trauma center. PATIENTS/PARTICIPANTS: One hundred fifty-eight intertrochanteric fractures in patients older than 65 years with an average follow-up of 22 months. INTERVENTION: Single-screw CMN fixation. MAIN OUTCOME MEASUREMENTS: Lag screw sliding and revision surgeries. RESULTS: The average amount of lag screw sliding was 5 ± 5 mm (range, 0-21 mm). Lag screw sliding was greater with unstable fracture patterns (mean difference 2 mm, 95% confidence interval 0.4-3.5 mm, P = 0.01) and calcar gapping >4 mm (mean difference 3.7 mm, 95% confidence interval 2-5 mm, P < 0.01). No association was found between lag screw sliding and age, female gender, implants, long versus short nails, distal interlock screw use, postoperative neck-shaft angle, or tip-apex distance (P > 0.05). Revision surgeries were performed in 6 (4%) patients. Indications included symptomatic lag screw removal (n = 2), avascular necrosis (n = 1), cutout (n = 1), loss of reduction (n = 1), and perimplant fracture (n = 1). CONCLUSIONS: Unstable fracture patterns are unavoidable; however, careful attention to calcar reduction and selection of dual-screw CMN implants may minimize lag screw sliding and its detrimental effects on outcomes. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
OBJECTIVES: To evaluate variables associated with lag screw sliding after single-screw cephalomedullary nail (CMN) fixation of intertrochanteric femur fractures. DESIGN: Retrospective cohort study. SETTING: Level-one trauma center. PATIENTS/PARTICIPANTS: One hundred fifty-eight intertrochanteric fractures in patients older than 65 years with an average follow-up of 22 months. INTERVENTION: Single-screw CMN fixation. MAIN OUTCOME MEASUREMENTS: Lag screw sliding and revision surgeries. RESULTS: The average amount of lag screw sliding was 5 ± 5 mm (range, 0-21 mm). Lag screw sliding was greater with unstable fracture patterns (mean difference 2 mm, 95% confidence interval 0.4-3.5 mm, P = 0.01) and calcar gapping >4 mm (mean difference 3.7 mm, 95% confidence interval 2-5 mm, P < 0.01). No association was found between lag screw sliding and age, female gender, implants, long versus short nails, distal interlock screw use, postoperative neck-shaft angle, or tip-apex distance (P > 0.05). Revision surgeries were performed in 6 (4%) patients. Indications included symptomatic lag screw removal (n = 2), avascular necrosis (n = 1), cutout (n = 1), loss of reduction (n = 1), and perimplant fracture (n = 1). CONCLUSIONS: Unstable fracture patterns are unavoidable; however, careful attention to calcar reduction and selection of dual-screw CMN implants may minimize lag screw sliding and its detrimental effects on outcomes. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Authors: G W L Hulshof; M van der Stelt; H Schutte; P J van Koperen; T K Timmers; G D J van Olden; W P Kluijfhout Journal: Eur J Orthop Surg Traumatol Date: 2022-08-17