[Surgical management of hallux valgus by techniques preserving the first metatarsophalangeal joint: long-term results].

PURPOSE OF THE STUDY: Hallux valgus is a frequent static deformity of feet in shoe-wearing populations. Lasting problems usually require surgical management. The authors evaluate the long-term results of such treatment by either McBride's operation or chevron osteotomy, or by combination of both.

MATERIAL: A group of 72 patients with hallux valgus underwent 84 operations, with the use of McBride's procedure, chevron osteotomy or a combination of both, at the First Department of Orthopedic Surgery, St. Anne's Teaching Hospital in Brno, in the years 1993-1995. At 10-year follow-up they were evaluated on the basis of patients' subjective satisfaction and the degree of correction measured by hallux valgus angle (HVA) and intermetatarsal angle (IMA).

METHODS: Surgery is carried out under general or spinal anesthesia, with application of a pneumatic tourniquet, after a standard preparation of the operating field. In the modified chevron osteotomy, a "V"-shaped osteotomy of the distal metatarsal is created (V-osteotomy angle is 70 to 80 degrees), which allows the first metatarsal head to be shifted laterally. The modified McBride's procedure is based on transposition of the adductor hallucis tendon onto the first metatarsal head; lateral sesamoidectomy may be necessary. A combination of both techniques involves V-shaped osteotomy of the first metatarsal bone and transposizion of the adductor hallucis tendon, with lateral sesamoidectomy, when necessary. These surgical procedures always include excision of a bursa at the first metatarsal head, removal of a medial eminence of the first metatarsal head and lateral capsulotomy of the first metatarsophalangeal joint. The authors evaluated: 1) the degree of correction by comparing the HVA and IMA on pre-operative radiographs with those measured at 10 years after surgery; 2) subjective satisfaction of the patients who received a questionnaire asking about big-toe position, pain, problems associated with footwear, sores over the metatarsophalangeal joint of the big toe and mobility of this joint.

RESULTS: Of the patients undergoing chevron osteotomy (20 procedures), 95 % reported satisfaction; the mean degree of correction was 13 degrees for HVA and 4 degrees for IMA. Of the patients undergoing McBride's procedure (45 operations), 60 % were satisfied; this group had the lowest mean degree of correction, i. e., 4.8 degrees for HVA and -0.6 degrees for IMA. Of the patients undergoing the combined technique (19 operations), 74 % reported satisfaction and the mean degree of correction was highest, i. e., 17.9 and 4.5 degrees for HVA and IMA, respectively. Two patients of this group developed hallux varus, but their HVA and IMA values were not included in the assessment because they would adversely affect the objective evaluation of all the patients. However, in the subjective evaluation of the whole group, these two unsatisfied patients were included.

DISCUSSION: In agreements with the majority of published results, the authors conclude that a higher correction is achieved with chevron osteotomy than with McBride's operation. Subjective satisfaction reported in the literature is not consistent, but it is either similar in both procedures or better in chevron osteotomy. In this study, chevron osteotomy resulted in high patient satisfaction (95 %), good correction (HAV, 13 degrees ; IMA, 4 degrees ) and a minimum of complications. McBride's procedure resulted in the lowest correction (HAV, 4.8 degrees ; IMA, -0.6 degrees ) as well as the lowest satisfaction (60 %). Our results show that younger patients (up to about 35 years) responded with better outcomes. The combined method achieved the highest degree of correction (HAV, 17.9 degrees ; IMA, 4.5 degrees ) and 74 % satisfaction, but was associated with the risk of hallux varus development.

CONCLUSIONS: If indication criteria are respected, surgical procedures are competently performed and good post-operative care is provided, it is not necessary to combine the operation techniques in order to achieve good long-lasting correction and patients' satisfaction.