[Evaluation of the Scarf osteotomy in hallux valgus related to distal metatarsal articular angle: a prospective study of 79 operated cases].

PURPOSE OF THE STUDY: The hallux valgus surgery concerns many operative techniques. The purpose of this report was to evaluate the radiographic results of the Scarf osteotomy related to Distal Metatarsal Articular Angle (DMAA).

MATERIAL AND METHODS: The Scarf osteotomy was performed on 79 feet with an hallux valgus deformity (75 females and 4 males from 16 to 82 years). Pre and postoperative weight-bearing X-rays were performed; We measured the Distal Metatarsal Articular Angle (DMAA), the intermetatarsal angle (M1-M2, M1-M5), the metatarsophalangeal angle, the obliquity of the metatarsocuneiform joint and the length of the first and second metatarsal.

RESULTS: All parameters were statistically significantly improved by the surgery. However correction on the DMAA was not sufficient (from 14.6 degrees to 12.6 degrees although normal value is 6 degrees). We found a correlation between the metatarsophalangeal angle and the DMAA.

DISCUSSION: The preoperative measures showed that the DMAA value increases with the value of the metatarsophalangeal angle; it is insufficiently decreased in comparison to the normal value. It has to be strongly taken in consideration in the preoperative evaluation.

CONCLUSION: The preoperative DMAA value is the most important factor in the hallux valgus evaluation. It determines if Scarf or other operative technique are indicated. Its normalisation may provide less recurrences.