Minimally Invasive Surgery for Severe Hallux Valgus with Severe Metatarsus Adductus: Case Reports

CATEGORY: Bunion; Lesser Toes INTRODUCTION/PURPOSE: Metatarsus adductus (MA) is a congenital transverse plane deformity with an incidence of approximately 30% in patients with hallux valgus. Operative treatment of hallux valgus (HV) with MA can be clinically challenging, and the recurrence rate of HV has been reported as two times higher than in patients without MA. Minimally invasive surgery (MIS) for the correction of HV is growing in popularity; however, only one study has been published on MIS for HV with MA using percutaneous proximal metatarsal osteotomy. We presented our case reports using distal oblique metatarsal minimal invasive osteotomy (DOMMO) for severe MA. METHODS: We corrected two feet using DOMMO for severe MA. Minimally invasive chevron Akin osteotomy (MICA) was utilized to correct severe HV. The patient had subluxations in the second and third metatarsophalangeal joints and hammer toe deformities. Therefore, those deformities were concurrently corrected using percutaneous procedures. The patient was allowed immediate full weight bearing postoperatively in a flat rigid shoe for 6 weeks. Radiographic and clinical evaluations were performed preoperatively and one year after surgery. On the anteroposterior radiograph, the hallux valgus angles (HVA), the first intermetatarsal angles (IMA), tibial sesamoid positions (TSP) and metatarsus adductusangles (MAA) were evaluated. On the lateral weight-bearing radiograph, first metatarsal inclination angles were also evaluated. We also evaluate the Japanese Society for Surgery of the Foot (JSSF) hallux and lesser toes scales and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) both before and after MIS for HV with MA. RESULTS: In the first case, the HVA improved from 50° to 16°, the IMA from 15° to 11°, TSP from 7 to 5 using Hardy's classification, and MAA from 27° to 14.5°, pre- to postoperatively. In the second case, the HVA improved from 45° to 11°, the IMA from 10° to 6.5°, TSP from grade 7 to 3, MAA from 30 to 12, pre- to postoperatively. The first metatarsal inclination angles changed from 16.9° and 18.8° to17.7° and 22.0°, respectively. All subluxations and hammer toe deformities were resolved. Although there were delayed unions in the lesser metatarsals, unions were achieved finally. Preoperative JSSF hallux scales and lesser toes scales were 59 points and 64 points, 67 points and 80 points, respectively. Both hallux and lesser toe scales improved to 100 points one year after surgery. All SAFE-Q subscores were also improved one year after surgery. CONCLUSION: In conclusion, our MIS procedure, consisting of DOMMO of the second, third, and fourth metatarsals and MICA, could correct severe HV with severe MA. The patient was allowed immediate full weight bearing postoperatively in a flat rigid shoe. Although there were delayed unions in lesser metatarsals, unions were finally achieved and good results were demonstrated both radiographically and clinically.