Fourth Generation Percutaneous Transverse Osteotomies for Hallux Valgus: A series of 729 feet

P Lam, A Newton, E Murphy, MJ Chua, R Ray, C Watt, P Robinson, M Dalmau-Pastor, T Lewis

Background: Fourth-generation percutaneous or minimally invasive hallux valgus surgery utilizes a transverse osteotomy to achieve deformity correction. There are only a small number of series reporting the clinical and radiological outcomes of transverse osteotomies, many of which have methodological limitations such as small sample size, limited radiographic follow up or use of non-validated outcome measures. The aim of this study was to provide a
methodological robust investigation into percutaneous transverse osteotomies for hallux valgus deformity.

Method: A prospective series of consecutive patients undergoing fourth generation metatarsal extra-capsular transverse osteotomy (META) performed by a single surgeon (PL) between November 2017 and January 2023. The primary outcomes were radiographic deformity correction and clinical foot function assessed using the Manchester- xford Foot questionnaire (MOXFQ). Radiographic deformity (Hallux valgus angle (HVA) and intermetatarsal angle (IMA),
sesamoid position) was assessed according to AOFAS guidelines. Secondary outcomes included Visual Analogue Scale for Pain and radiographic deformity recurrence (defined as HVA >20° at final radiographic follow up).

Results: 729 feet from 483 patients (456 Female, 27 Male, mean age 57.9±11.9 years) underwent META. Radiographic data (minimum 12 months post-surgery) was available for 99 .7% of feet with mean follow up of 2.6±1.3 years (range 1.0-5.7). There was a statistically significant improvement (p<0.05) in both HVA; 29.5±8.5° to 7.3±6.7°, and IMA, 12.9±3.4° to 4.6±2.5°. All MOXFQ domains showed significant improvement (p<0.05); Index 36.6±19.1 to 11.8±13.8, Pain 40.1±22.1 to 15.6±16.4, Walking/Standing 32.2±23.2 to 10.2±15.8 and Social Interaction 40.0±20.6 to 9.7±14.0. The recurrence rate was 4.5% (n=33). The complication rate was 6.1% which included a screw removal rate of 2.9%.

Conclusion: This is the largest consecutive series of any percutaneous osteotomy technique to correct hallux valgus deformity. This study demonstrates that the technique leads to significant improvement in clinical and radiographic outcomes with a low rate of recurrence.