Abstract
Category:
Bunion; Midfoot/Forefoot
Introduction/Purpose:
The majority of hallux valgus (HV) corrections have been historically performed via a two-dimensional, transverse plane-focused approach, which has demonstrated high long-term recurrence rates. Recent research demonstrates that 87% of HV deformities are three-dimensional with abnormal frontal-plane rotation of the metatarsal, which cannot be completely addressed with a two-dimensional metatarsal osteotomy alone. While correction at the 1st tarsometatarsal (TMT) joint may provide the optimal surgical approach for 3D anatomic restoration at the apex of the deformity, 1st TMT arthrodesis historically entails an extended period of non-weightbearing. This study evaluated the clinical, radiographic, and patient-reported outcomes in patients undergoing instrumented triplanar 1st TMT arthrodesis (TMTA) with a biplanar plating system and protected early weightbearing.
Methods:
This is a prospective multicenter study that will continue for 60 months post-operatively. Patients 14-58 years old with symptomatic HV (intermetatarsal and HV angles between 10-22° and 16-40°, respectively) and no prior HV surgery on the operative foot were eligible for this study. Patients were treated with an instrumented TMTA procedure using a biplanar plating system with protected early weightbearing. The primary endpoint of this study is radiographic recurrence of HV, with recurrence reported at two different thresholds commonly utilized in the literature: post-operative HVA > 15° and HVA > 20°. Secondary outcomes (changes in radiographic measurements, return to weightbearing and activities, VAS, MOxFQ, and PROMIS-29) were evaluated for statistically significant post-operative improvements.
Results:
173 patients (mean [range] age: 41.0 [14-58] years) underwent TMTA, of whom 136 and 74 have completed 36-month and 48-month visits, respectively. Mean (95% CI) days to protected weightbearing and return-to-full-work were 8.4 (7.3, 9.5) and 57.9 (50.8, 65.0), respectively. Significant improvements in HVA, IMA, TSP, and sagittal-IMA were maintained through 48 months (Table 1). Applying recurrence definitions of post-operative HVA >15° and >20°, 36-month recurrence rates were 6.1% (8/132) and 1.5% (2/132) and 48-month’s were 6.9% (5/72) and 0.0% (0/72 patients), respectively. Significant improvements over baseline were observed in VAS pain score (81% reduction, N =156 at 24 months) and PRO’s, including all domains of MOxFQ and PROMIS through 48 months. Fourteen (8.1%) patients required non-elective reoperation (most commonly HWR) and 3 (1.8%) experienced symptomatic nonunion.
Conclusion:
The results of this study’s primary and secondary endpoints provide supporting evidence that TMTA with biplanar plating is successful in correcting the 3D hallux valgus deformity with early return to weightbearing and low recurrence while demonstrating favorable clinical and patient-reported outcomes. Patients exhibited meaningful pain reduction after surgery and were able to return to full, unrestricted work and activities in less than two months, on average. Statistically significant improvements in patients’ health-related quality-of-life were observed through 48 months, post-operatively. Patients will continue to be followed for up to 60 months with additional evaluations for complications, recurrence, and patient satisfaction.
