Immediate weight-bearing after locking plate fixation of the Ludloff osteotomy

Abstract

Category: Bunion Introduction/Purpose: One of the more common and versatile osteotomies to correct moderate hallux valgus deformities is the Ludloff osteotomy. This oblique osteotomy is typically stabilized with screws and patients kept non-weight bearing until healed. Complications include malunion, nonunion and loss of correction, which can occur due to poor compliance with non- weight bearing protocols. Elderly, obese and physically weak patients can have difficulty remaining non-weight bearing. A novel anatomic-locking plate and fixation method was developed that allows immediate weight bearing after a Ludloff osteotomy. We analyzed the results of a consecutive cohort of patients who underwent a Ludloff osteotomy stabilized with this method. The cohort included all patients presenting with a moderate to severe hallux valgus deformities. Complications, radiographic & clinical outcomes were studied. Methods: In this IRB approved retrospective cohort study, we analyzed clinical & radiographic data of all Ludloff osteotomies performed between 2010 and 2015. Preoperative and postoperative data included Foot Function Index, intermetatarsal & hallux valgus angles, complications, callus formation & clinical outcomes. 395 feet in 350 patients were examined. 6 patients (2.1%) were male. 43 feet were excluded due to incomplete films and 21 were excluded due to screw fixation only; requiring restricted post- operative weightbearing protocols. Three surgeons performed the surgeries and review/analyses conducted by a senior orthopedic resident, uninvolved with the care of any of the patients. Indications included symptomatic hallux valgus deformities (intramedullary angle greater than 10°), failure of conservative treatment and normal preoperative range of motion. Exclusion criteria included 1st tarsometatarsal joint arthritis/instability, peripheral neuropathy, vascular disease and 1st metatarsophalangeal joint arthritis. Preoperative and postoperative radiographs were weightbearing. Patients discharged when comfortable in normal shoes. Results: At an average of 8 months postop (2 - 43 months), there was an average hallux valgus (HVA) correction angle correction of 7.6° (p<.0001) and intermetatarsal angle (IMA) correction of 21° from initial to final radiographs. Patients were discharged when comfortable in normal shoes. In the 15 feet (4.6%) who formed hypertrophic callus, there was loss of IMA of 2.3° (p<.0001) and HVA of 4.6° (p<.0001). Superficial wound infection or mild cellulitis was noted in 16 feet (4.9°); no deep infections. 15 (4.6%) feet had hardware removal due to prominent and/or broken screws. These were in older women with thin feet. There was only 1 nonunion & 8 mal-unions. An average foot function index (in 70 patients) of 9.5/100 indicated low pain and disability. Conclusion: The data from this large series of patients (395 osteotomies) supports the use of an immediate weight-bearing protocol for Ludloff osteotomies fixed with anatomic locking plates, including patients with osteopenic bone. All patients were allowed activities and weight bearing as tolerated during the post-operative period. There were relatively few complications including loss of correction or nonunion. Patients and surgeons can expect healing and complication rates similar to osteotomies fixed with screws and a non-weight-bearing post-operative protocol. Furthermore, because of the increased stability imparted by the anatomic locking plate, it would be a good option for revision bunion surgery.