Evaluation of hallux valgus treatment: is classical angular correction approach relevant?

Hallux valgus correction is mostly done by metatarsal procedures, and widely accepted strategy is to decide which surgical method should be used is based on radiological severity using intermetatarsal (IMA) and hallux valgus (HVA) angles (classical angular correction approach-CACA). The aim of the study is to compare the postoperative improvement in radiographic parameters and morphologic appearance of the foot between patients operated with and without adhering to CACA strategy based on classical severity classification using angle measurements.

A retrospective comparative study between two groups (conforming and not conforming to proposed algorithm) was performed. Of 122 feet of 119 patients underwent metatarsal procedures for hallux valgus between October 2022 and November 2023, 92 feet of 92 patients were enrolled in the study (age 43.86 ± 16.1 years, 15.2% male). Patients were classified into two groups as conforming and non-conforming to CACA algorithm based on IMA and HVA angles (mild: IMA ≤ 13°, HVA ≤ 30°; moderate: 13° < IMA < 20°, 30° < HVA < 40°; severe: IMA ≥ 20°, HVA ≥ 40°). Algorithm proposed distal osteotomies for mild cases, shaft osteotomies for moderate cases and proximal osteotomies or tarsometatarsal arthrodeses for severe cases. HVA and IMA corrections after surgery, bony foot width, soft tissue foot width, medial eminence bony distance and medial soft tissue distance alterations, American Orthopaedic Foot and Ankle Society Metatarsophalangeal-Interphalangeal Scale (AOFAS-MTP-IP) scores and improvement of foot appearance according to Manchester scale in postoperative first year follow-up were compared between groups.

58 procedures (group 1) conformed CACA, while 34 (group 2) did not. There was no statistically significant difference in terms of IMA (3.81° ± 4.01°, 2.72° ± 2.25°, p = 0.423), HVA (12.78° ± 7.81°, 10.31° ± 5.4°, p = 0.106) bony forefoot width (4.41 ± 6.66 mm, 1.65 ± 6.67 mm, p = 0.059), soft tissue forefoot width (1.21 ± 6.61 mm, 2.41 ± 7.45 mm, p = 0.423), medial eminence width (5.72 ± 3.17 mm, 6.07 ± 3 mm, p = 0.609) alterations and AOFAS-MTP-IP scores (82.17 ± 5.26, 83.06 ± 5.18, p = 0.435) between groups. Medial soft tissue width increased in both groups (2.74 ± 2.53 mm, 1.48 ± 1.67 mm, p = 0.011). Manchester stages were improved in 45 feet in group 1 (77.6%) and 19 feet in group 2 (55.9%) (p = 0.029).

The CACA strategy of treating more severe deformities with more proximal procedures and milder deformities with distal osteotomies did not significantly impact postoperative radiologic parameters. Nonetheless, following CACA strategy is likely to improve the morphologic appearance of the foot.

III, comparative study.