Léo Nanty1, François Canovas1, Thibaut Rodriguez1, Patrick Faure1, Louis Dagneaux2. 1. Département de Chirurgie Orthopédique et Traumatologie, Unité de Chirurgie du membre inférieur et du rachis, Hôpital Lapeyronie, CHRU de Montpellier, 351, avenue Gaston-Giraud, 34295 Montpellier cedex 5, France. 2. Département de Chirurgie Orthopédique et Traumatologie, Unité de Chirurgie du membre inférieur et du rachis, Hôpital Lapeyronie, CHRU de Montpellier, 351, avenue Gaston-Giraud, 34295 Montpellier cedex 5, France. Electronic address: louisdagneaux@gmail.com.
Abstract
BACKGROUND: Arthroplasty has not been proven superior over internal fixation for the treatment of non-displaced femoral neck fractures. However, internal fixation has been followed by high rates of revision for mechanical complications and of femoral neck impaction within the first postoperative year. The objective of this study was to determine whether femoral neck impaction was associated with avascular necrosis (AVN). HYPOTHESIS: Fracture healing with femoral neck shortening by impaction after internal fixation of a femoral neck fracture is associated with AVN. MATERIAL AND METHODS: A single-centre retrospective study in patients with Garden I fractures managed by screw fixation was performed to compare outcomes in the groups with and without femoral neck impaction. Follow-up radiographs were assessed for evidence of the femoral neck impaction during fracture healing. The occurrence of AVN was the primary evaluation criterion. The secondary evaluation criteria were risk factors for impaction and complications. RESULTS: Of the 75 included patients, 9 (12%) experienced AVN. Impaction was significantly associated with AVN (p=0.02; relative risk, 4.38). Significant risk factors for impaction were a higher body mass index (p=0.0003) and valgus-impacted fracture reduction between the radiographs at baseline and immediately after surgery (p=0.0001). DISCUSSION: Femoral neck impaction was a significant risk factor for AVN after screw fixation of Garden I fractures. Valgus-impacted fracture reduction must receive careful attention during fixation. We suggest static internal fixation if the impaction is reduced on a traction table and advise caution when using parallel screws. The diagnostic and therapeutic strategy proposed here deserves to be evaluated in a prospective study. LEVEL OF EVIDENCE: III, retrospective comparative study.
BACKGROUND: Arthroplasty has not been proven superior over internal fixation for the treatment of non-displaced femoral neck fractures. However, internal fixation has been followed by high rates of revision for mechanical complications and of femoral neck impaction within the first postoperative year. The objective of this study was to determine whether femoral neck impaction was associated with avascular necrosis (AVN). HYPOTHESIS: Fracture healing with femoral neck shortening by impaction after internal fixation of a femoral neck fracture is associated with AVN. MATERIAL AND METHODS: A single-centre retrospective study in patients with Garden I fractures managed by screw fixation was performed to compare outcomes in the groups with and without femoral neck impaction. Follow-up radiographs were assessed for evidence of the femoral neck impaction during fracture healing. The occurrence of AVN was the primary evaluation criterion. The secondary evaluation criteria were risk factors for impaction and complications. RESULTS: Of the 75 included patients, 9 (12%) experienced AVN. Impaction was significantly associated with AVN (p=0.02; relative risk, 4.38). Significant risk factors for impaction were a higher body mass index (p=0.0003) and valgus-impacted fracture reduction between the radiographs at baseline and immediately after surgery (p=0.0001). DISCUSSION: Femoral neck impaction was a significant risk factor for AVN after screw fixation of Garden I fractures. Valgus-impacted fracture reduction must receive careful attention during fixation. We suggest static internal fixation if the impaction is reduced on a traction table and advise caution when using parallel screws. The diagnostic and therapeutic strategy proposed here deserves to be evaluated in a prospective study. LEVEL OF EVIDENCE: III, retrospective comparative study.
Authors: Marcel Niemann; Karl F Braun; Sufian S Ahmad; Ulrich Stöckle; Sven Märdian; Frank Graef Journal: Medicina (Kaunas) Date: 2022-02-26 Impact factor: 2.430