Percutaneous Fifth Metatarsal Osteotomy for Bunionette Deformity Without Fixation or Strapping: A Retrospective Study

Abstract

Background: Bunionette deformity (BD) is a painful condition of the fifth metatarsal characterized by an osseous prominence and fifth toe varus deformity. The purpose of this study is to assess the clinical, functional, and radiographic outcomes of percutaneous distal metatarsal metaphyseal osteotomy (DMMO) without fixation or postoperative strapping of the foot. Methods: A retrospective case series was performed on 111 patients (132 feet) with symptomatic BD who underwent percutaneous DMMO of the fifth metatarsal from September 2020 to January 2022 by an experienced minimally invasive surgeon. According to the Shimobayashi classification, we treated 1 type I deformity, 37 type II deformities, 52 type III deformities, 42 feet with type IV deformity, and no patient with a type V deformity. Ninety patients (81%) underwent unilateral osteotomy, and 21 (19%) had bilateral osteotomies. Most cases included other procedures including treatment of 114 associated deformities of the same feet: 68 bunions, 12 lesser metatarsal osteotomies (2-3-4 metatarsals), and 34 hammertoes (20 second hammertoes, 10 third hammertoes, 1 fourth hammertoes, 2 fifth hammertoes). Patient-reported clinical outcome measures, including the Foot Function Index (FFI) questionnaire, the visual analog score (VAS), and overall satisfaction were collected. Fourth-to-fifth intermetatarsal angle (IMA) correction, time to bone union, and complication rates were assessed in all patients. Results: Mean follow-up was 24.1 months (range, 14-39 months). Both radiographic parameters and patient-reported outcome measures significantly improved after DMMO procedure. The average fourth-to-fifth IMA improved from 12.2 degrees, preoperatively, to 4.4 degrees, postoperatively ( P < .001). Patient outcomes reflect the overall outcomes of the combined surgeries on a per-patient basis. Preoperatively, patients had a mean VAS score of 7.6, which improved to 0.6 at the last follow-up ( P < .001). Furthermore, the average FFI significantly decreased from pre- to postoperation from 19.2 to 4.4, respectively ( P < .001). Overall, 108 of 111 patients reported being satisfied with the outcomes of the procedure. Average bone union was achieved at 12.6 weeks postoperation, with a minimum of 12 and a maximum of 25 weeks. The complication rate was 1.5%, including 1 case of an asymptomatic cock-up deformity and 1 case of lateral fifth metatarsal shaft bone overhang pain, which resolved with an exostectomy. Conclusion: The results of this study of patients who had minimally invasive surgery from an experienced surgeon suggest that percutaneous DMMO of the fifth metatarsal without internal fixation or postoperative immobilization or strapping can be effective at improving radiographic alignment, pain, function, and overall satisfaction with minimal rates of complication. Level of Evidence: Level IV, case series.

Effects of functional treatment of V metatarsal bone fracture in athletes – an evaluation of cases

“…The study reported that the functional therapy resulted in excellent clinical outcomes after an average follow-up of 22 months, with no significant differences based on the type of fracture. 38 This approach aligns with the findings of, 39 who suggested that athletes with fifth metatarsal fractures may benefit from surgical screw fixation, leading to optimal healing within approximately 7 to 12 weeks after surgery. However, Baumbach et al demonstrated that functional treatment without stabilization also yielded positive outcomes, emphasizing early return to activities and sports.…”

“…However, Baumbach et al demonstrated that functional treatment without stabilization also yielded positive outcomes, emphasizing early return to activities and sports. 38 Furthermore, Chu et al 3 highlighted the importance of a conservative approach, including rehabilitative exercises and various therapies, in the nonoperative management of fifth metatarsal fractures. This aligns with the functional treatment approach employed by Baumbach et al, where patients were not subjected to any form of stabilization but were encouraged to resume activities early, resulting in successful outcomes.…”

Universal Percutaneous Treatment of Bunionette: Myth or Reality?

“…In this issue of FAI, Al Ramwali et al assess the results of a percutaneous technique, the minimally invasive distal metatarsal osteotomy of the 5th ray (DMMO 5) to treat bunionette. 1 They report excellent results in a fairly large series, with very few complications (1.5%), which can be considered minor. The postoperative period is that of a percutaneous procedure without fixation, with the wearing of a flat postoperative shoe for a few weeks, before resuming comfortable footwear around the 6th week, and physical activities after 3 months.…”

“…In this issue of FAI, Al Ramwali et al assess the results of a percutaneous technique, the minimally invasive distal metatarsal osteotomy of the 5th ray (DMMO 5) to treat bunionette. 1…”