Abstract
Purpose: To evaluate the effect of shortening scarf osteotomy on pain relief and range of motion (ROM) of the first metatarsophalangeal joint in hallux rigidus patients. Materials and Methods: Twenty-three cases of 19 patients who had been treated with shortening scarf osteotomy for the hallux rigidus between January 2007 and December 2013 were reviewed. The mean follow-up period was 21.4 months, and the mean age was 59.2 years. The first metatarsal bone was shortened until the ROM of the first metatarsophalangeal joint was greater than $80^{\circ}$ or $40^{\circ}$ of dorsiflexion. The length shortened by scarf osteotomy was measured. The authors also measured and compared the joint interval difference of the standing foot using an anteroposterior radiography. Moreover, the difference of ROM of the first metatarsophalangeal joint between the preoperative and final follow-up periods was also compared. The clinical results were evaluated and compared using the American Orthopaedic Foot and Ankle Society (AOFAS) scoring system and visual analogue scale (VAS) score. Results: The mean shortening length was about 6.5 mm (range, 4~9 mm). The joint space has been increased to 1.8 mm, and the ROM of the first metatarsophalangeal joint has also been increased to $18.4^{\circ}$ after the operation. In three cases, the postoperative ROM has been decreased to less $10^{\circ}$. The AOFAS score has been improved from 41.7 (range, 32~55) to 86.2 (range, 65~95), and the VAS score was also decreased from 3.7 (range, 3~5) to 1.3 (range, 0~3). Two cases have shown no decrease in pain even after the operation. Conclusion: Shortening scarf osteotomy was found to decrease joint pain by decompressing the pressure of the first metatarsophalangeal joint. This osteotomy also helped improve the ROM of the first metatarsophalangeal joint. Shortening scarf osteotomy can be considered one of the effective methods for joint preservation.