[Our results of the Lapidus procedure in patients with hallux valgus deformity]

The most frequent deformity of the big toe and forefoot associated with a collapse of the transverse arch of the foot is a valgus deformity. For correction of a hallux valgus, several procedures are described in the literature. A valgus deformity often develops due to a varus deviation of the first metatarsal bone when the intermetatarsal angle between the first and second metatarsals is greater than 10 degrees. When the intermetatarsal angle is larger then 10 degrees or the first ray is hypermobile, a Lapidus procedure is one of the options. The objective of this study was to evaluate the outcomes in patients with hallux valgus deformity treated by the Lapidus procedure.

The group comprised 61 patients, 49 women and 12 men, with an average age of 58.3 years at the time of surgery, who were treated at our department in the period from 2002 to 2006. Fifteen patients had bilateral surgery. The results of 76 operations were evaluated. Indications for surgery were hallux valgus in 22 patients, rheumatoid arthritis in 36 and psoriatic arthritis in three patients.

Access was gained on the mediodorsal side of the foot through an incision medial to the extensor hallucis longus tendon, over the first tarsometatarsal joint up to the first metatarsophalangeal joint. An arthrodesis was fixed with two Kirschner wires in eight feet and with two screws in 15 feet. Recently, the use of shape memory alloy staples (DePuy Mitek) was adopted and applied in 53 feet with good outcome. In the patients with rheumatoid arthritis the Lapidus procedure together with resection of the heads of the second and fifth metatarsals was used from the plantar approach.

The evaluation was focused on the patients' satisfaction and their subjective complaints. No pain was reported on 56 (73%) forefeet, slight pain was experienced on the dorsal side in ten feet (13%) and pain in the transverse arch also in ten feet (13%). Complications included slow healing of the wound in seven feet of the patients with rheumatoid arthritis (9.2%), and infection requiring revision surgery in one patient (1.3%). Five patients (6.5%) reported persisting swelling of the foot dorsum for a period longer than 3 months. Recurrence of hallux valgus was recorded in nine feet. The average American Orthopaedic Foot and Ankle Society score, which was 48.1 points pre-operatively, improved to 89.2 points post-operatively. In one patient, bony union was very slow and was achieved at 5 months after surgery.

An exact evaluation of the results of a Lapidus procedure is not always possible, particularly in patients with rheumatoid arthritis in whom foot disorders are more complex. A much discussed issue is first metatarsal hypermobility. In our group of 61 patients, this was found in 28. Of these, 18 had rheumatoid arthritis and ten had hallux valgus. The rate of pseudoarthrosis following a Lapidus procedure is reported to range from 3.3% to 9%. In our group only one patient was affected (1.3%).

A correctly performed: Lapidus procedure enables us, by correcting a varus deviation of the first metatarsal, to repair valgus deformity of the big toe resulting in painless walking.