Performed by – David Hinsley, Ngwe Phyo, Nick Ward

Hallux Valgus (Bunion) corrective surgery
Patients with Hallux Valgus (Bunion) usually complain of a painful bump on the medial (inside) of the great toe (Hallux) metatarsophalangeal (MTP) joint. The hallux moves towards the second toe occasionally causing crossover of toes.

The tendons that pass under the metatarsal head have two bones within them (sesamoids). The best example of a sesamoid bone is the knee cap. Sesamoid bones are present when a tendon is likely to be but under great stress (60% of your bodyweight goes through the hallux MTP joint when walking). Over time, the metatarsal head falls medially off the sesamoid platform, leaving the lateral sesamoid uncovered. The tendons attached to the hallux pull the toe into further valgus and worsen the metatarso-sesamoid subluxation.

Ultimately, the weight bearing function of the great toe becomes compromised and lateral metatarsalgia (forefoot pain) may result as weight bearing is transferred laterally.

The operation aims to reposition the metatarsal head over the sesamoids and restores the normal weight bearing properties of the metatarsal. By narrowing the intermetatarsal angle (and removing the medial bump), it reduces the forefoot splaying as well as the overall width of the forefoot.

The following diagrams demonstrate how the metatarsal head is moved medially and fixed using special screws.

Post-operative rehabilitation
Weight bearing is allowed in a flat post operative shoe for the first 6 weeks. However, patients are advised to keep the foot elevated as much as possible for the first 2 weeks. Sutures are removed after 10-14 days and the patient taught to do perform their own bandaging and encouraged to mobilise the great toe.

Radiographs are performed after 6 weeks to check the position of the osteotomy and the progression of union. At this point the flat post operative shoes are discarded and the patient commences in normal footwear.

The foot is likely to be sore for the first three months following surgery and that the result depends upon compliance with the post-operative bandaging and mobilisation regime. In addition, you may not be able to wear a shoe comfortably until 16 weeks and that the full recovery (including the resumption of sport) may take up to 12 months.