Surgical strategies for atypical femoral fracture nonunion: Augmentative plating with or without exchange nailing.

Abstract

This study investigated the outcomes of augmentative plating, with or without exchange nailing, in treating AFF nonunion. Ten female patients who underwent augmentative plating with or without exchange nailing for AFF nonunion were retrospectively analyzed. To measure bone remodeling suppression, preoperative bone turnover markers (BTMs) were evaluated. The key outcome measures were the effectiveness of screw fixation in plating, malalignment correction via neck-shaft angle (NSA) adjustments, and improvements in ambulatory function assessed by the Koval score. Of the 10 patients, six underwent exchange nailing with augmentative plating and four underwent augmentative plating alone. This strategy resulted in bone union in all patients within a median of 21.5 weeks (range: 12-33 weeks). All cases presented loosening signs, indicating the mechanical instability challenges inherent in AFF nonunion. Mechanical stability was improved by securing an average of 4.8 ± 3.2 and 4.6 ± 2.5 cortices in proximal and distal fragments, respectively, through augmentative plating. Six cases exhibited varus malalignment, which was successfully corrected. Analysis revealed that preoperative BTMs were normalized in most patients who had discontinued bisphosphonate or denosumab, suggesting that bone remodeling suppression could be recovered before surgery. The Koval score decreased from a median of 3.5 preoperatively to 2.0 one year post-surgery, indicating a considerable recovery in walking ability. Correcting malalignment and using augmentative plating for rigid fixation were effective in treating AFF nonunion.