We carried out a cross-sectional study in 51 patients (81 feet) with a clawed hallux in association with a cavus foot after a modified Robert Jones tendon transfer. The mean follow-up was 42 months (9 to 88). In all feet, concomitant procedures had been undertaken, such as extension osteotomy of the first metatarsal and transfer of the tendon of the peroneus longus to peroneus brevis, to correct the underlying foot deformity. All patients were evaluated clinically and radiologically.

The overall rate of patient satisfaction was 86%. The deformity of the hallux was corrected in 80 feet. Catching of the big toe when walking barefoot, transfer lesions and metatarsalgia, hallux flexus, hallux limitus and asymptomatic nonunion of the interphalangeal joint were the most frequent complications. Hallux limitus was more likely when elevation of the first ray occurred (p = 0.012). Additional transfer of the tendon of peroneus longus to peroneus brevis was a significant risk factor for elevation of the first metatarsal (p < 0.0001).

The deforming force of extensor hallucis longus is effectively eliminated by the Jones transfer, but the mechanics of the first metatarsophalangeal joint are altered. The muscle balance and stability of the entire first ray should be taken into consideration in the management of clawed hallux.