Medial augmentation plating of aseptic distal femoral nonunions

Abstract

Background: Distal femur nonunions are well-recognized contributors to persistent functional disability, with limited data regarding their treatment options. In the current study, we asked whether additional medial augmentation plating is a feasible treatment option for patients with aseptic distal femoral nonunion and intact lateral implants.

Methods: We conducted a single-center, retrospective study including 20 patients treated for aseptic distal femoral nonunion between 2002 and 2017. The treatment procedure included a medial approach to the distal femur, debridement of the nonunion site, bone grafting and medial augmentation plating utilizing a large-fragment titanium plate. Outcome measures were bone-related and functional results, measured by the Hospital for Special Surgery Knee Rating Scale (HSS) and the German Short Musculoskeletal Function Assessment questionnaire (SMFA-D).

Results: Eighteen of 20 nonunions showed osseous healing at 8.16 ± 5.23 (range: 3-21) months after augmentation plating. Regarding functional results, the mean HSS score was 74.17 ± 11.12 (range: 57-87). The mean SMFA-D functional index was 47.38 ± 16.78 (range 25.74-71.32) at the last follow-up. Index procedure-associated complications included two cases of persistent nonunion and one case of infection.

Conclusions: According to the assessed outcome measures, augmentation plating is a feasible treatment option, with a high proportion of patients achieving bony union and good functional outcomes and a few patients experiencing complications.

Keywords: Augmentation plating; Distal femur; Femoral nonunion; Implant failure; Medial plate; Pseudarthrosis.

Fig. 1

A Initial CT scan of an OTA type 33 – C2.3 distal femoral fracture of a 55-year-old male after a motorcycle accident. B X-rays showing ORIF with a lateral locking plate. C Nonunion six months after initial treatment. D Postoperative X-rays after revision utilizing a medial augmentation plate. E Final X-rays of the same patient showing bony healing six months after revision

Fig. 2

A Initial AP and lateral radiographs from a 24-year-old male with a BMI of 40.36 who was referred with hypertrophic nonunion with a stable in situ locking plate construct. B Postoperative X-rays after revision with complete debridement of the nonunion site, bone grafting and medial augmentation plating with a locking plate. C The patients’ final AP and lateral X-rays showing bony healing of the nonunion