SLR - July 2023 - Justin K. Metli, DPM, MA
Title: Ulcer occurrence on adjacent toes and hallux valgus deformity after amputation of the second toe in diabetic patientsReference: Unterfrauner, I., Andronic, O., Viehöfer, A.F. et al. Ulcer occurrence on adjacent toes and hallux valgus deformity after amputation of the second toe in diabetic patients. J Orthop Surg Res 18, 99 (2023)
Level of Evidence: Level IV
Reviewed by: Justin K. Metli, DPM, MA
Residency Program: Regions Hospital/HealthPartners Institute, Saint Paul, MN
Podiatric Relevance: Lesser digit amputations are a common podiatric procedure that results from ulcerations becoming infected leaching into the bone causing osteomyelitis. Osteomyelitis often requires a combination of medical and surgical treatment. Conservatively there are long term IV antibiotics and local wound cares, however it can be difficult to cure and alone has little chance of preventing reoccurrence. Often surgical intervention is needed to help treat and prevent further spreading of the infection. Transfer lesions are of concern following digit amputations as well as drifting of the remaining toes. This study retrospectively analyzed patients with amputation of the second toe with the goal of investigating its effects on the occurrence of transfer lesions and hallux valgus (HV) deformity.
Methods: A level IV retrospective study was performed to identify possible influencing factors on interdigital ulceration and hallux valgus deformity development following second digit amputations. Factors that were considered were if applicable, timing of the development of an interdigital lesion, Body mass index (BMI), shape of the metatarsal head, multiple radiographic angles, and the level of the amputation site. All of these parameters were analyzed by two orthopedic surgeons.
Results: A total of 23 patients (24 cases) who underwent a second toe amputation between 2004 and 2020 were included. Mean follow-up was 36 (+ or – 15) months postoperatively. Interdigital ulcer development on adjacent toes occurred in 50% of cases with the average appearance occurring around 20 (+ or – 11) months following amputation of the second toe. Nineteen (79%) of patients either developed or had progression of HV deformity post-amputation, however this was weakly correlated with increased risk for ulceration post-amputation. BMI and level of amputation were weakly correlated while the shape of 1st metatarsal head was weakly negatively correlated with development of interdigital ulcerations. Correlation with HV development had no significant difference between a high or low BMI, shape of the 1st metatarsal head, or level of amputation that correlates with increased chance for progression of or development of HV deformity.
Conclusions: The authors conclude, once amputation of the second toe occurs, 50% of patients will develop transfer lesions within 20 months along with increases in hallux valgus angles. However, both complications were found to have no certain influencing factors. Thus, demonstrating the role of proper diabetic foot care following digit amputations, especially within the first 20-months. Overall, this article sheds light onto proper remedies to prevent transfer lesions and drifting of the adjacent digits. Getting your patients into proper diabetic shoes and inserts, increasing their awareness of daily foot checks and yearly examinations by a podiatrist, and stressing the importance of not going barefoot especially with peripheral neuropathy involvement. When getting the patient into custom shoes/inserts utilizing a placeholder for the amputated digit can decrease drifting into the unoccupied space. All these parameters can decrease the chance of transfer lesions to adjacent toes. However, this study has its limitation of being underpowered and further higher-level studies are needed to further evaluate these clinical outcomes associated with second toe amputations.