Background: Hallux valgus (HV) is a common adult foot deformity. There is uncertainty concerning the effect of HV surgery on foot width. We examined the effect of chevron first metatarsal osteotomy on forefoot width using calibrated pre and postoperative standing radiographs.
Methods: A retrospective cohort of 50 patients underwent chevron osteotomy HV surgery. All had HVA > 30°, IMA > 11°, DMMA > 3°, >6-month follow-up, and calibrated pre and postoperative standing foot radiographs. Bony width (BW) and soft tissue width (STW) were used to measure the surgery's effect on foot width. Measurements were made preoperatively and 3-6 months following surgery.
Results: The study group included 42 women with an average age of 63.4 (±8.3) and a mean BMI of 28.7 (±4.9). Preoperative HVA and IMA were 31.7° (±6.8°) and 13.4° (±2.8°), respectively. Following surgery, HVA and IMA improved significantly, by 15.6° (±5.7°) and 8.7° (±2.3°), respectively. The preoperative average BW was 9.4 cm (±0.6), and the STW was 10.6 cm (±0.7). Following surgery, significant changes in BW and STW were measured, with a mean narrowing of 1.2 cm (±0.4) in BW (p < 0.001) and 0.95 cm (±0.5) in STW (p < 0.001). Paradoxically, an increase in age led to a lower correction of the IMA (p = 0.04, r = 0.57), but higher BW and STW reductions (p = 0.01, r = 0.35 and p = 0.008, r = 0.37, respectively).
Conclusions: This study reinforced chevron osteotomy as a valid treatment option that significantly narrows forefoot width; it is thus expected to improve cosmetic outcomes, shoe selection options, and quality of life. This study also found that older age correlates with better forefoot narrowing following hallux valgus repair, possibly due to stiffer soft tissues.
Keywords: chevron osteotomy; forefoot width; hallux valgus (HV); shoe size.