Radiographic and Clinical Outcomes of Intermetatarsal Screw Fixation in First Tarsometatarsal Arthrodesis for Hallux Valgus

Background: First tarsometatarsal (TMT) arthrodesis is a surgical option for moderate to severe hallux valgus, particularly in the setting of first-ray instability. The use of a supplemental intermetatarsal screw (IMS) has emerged as a technique intended to enhance transverse plane stability and may help maintain correction; however, limited clinical data exist regarding its radiographic and complication profile. This study compared radiographic correction, maintenance of alignment, and postoperative complications following TMT arthrodesis with vs without IMS fixation. Methods: A retrospective review was performed of adult patients who underwent first TMT arthrodesis for hallux valgus from 2013 to 2023 at a tertiary academic center. Patients undergoing additional midfoot fusion or with <6-month follow-up were excluded. Patients were grouped by whether supplemental IMS fixation was used, which was determined at surgeon discretion. Demographic, operative, and clinical data were recorded. Radiographic measurements included intermetatarsal angle (IMA) and relative first metatarsal (MT) length preoperatively, immediately postoperatively, and at latest follow-up. Results: Eighty-nine patients met criteria (51 IMS; 38 no IMS). Baseline demographics and comorbidities were similar between groups. Immediately postoperatively, the IMS cohort demonstrated a smaller IMA (5.8 vs 7.8 degrees, P = .010), which persisted at latest follow-up (7.3 vs 9.3 degrees, P = .015). The IMS group demonstrated a greater reduction in IMA from preoperative to final follow-up (6.9 vs 3.9 degrees, P = .001). Relative first MT length remained greater in the IMS cohort across all time points ( P ≤ .045) but change‑score (Postop-Preop) differences in length were not statistically significant. Complication rates, including nonunion (2.0% vs 2.6%), revision surgery (9.8% vs 18.4%), and hardware-related complications (7.8% vs 2.6%), did not differ significantly between groups ( P > .05). Conclusion: Supplemental IMS fixation in first tarsometatarsal arthrodesis for hallux valgus was associated with greater maintenance of radiographic correction without observed differences in complication rates. These findings support IMS augmentation as a potential adjunct in appropriately selected patients. Level of Evidence: Level III, retrospective review.