Evaluation of factors associated with surgical site infection in equine proximal interphalangeal joint arthrodesis: 54 cases (2010-2019).

BACKGROUND: The frequency of surgical site infection (SSI) following orthopaedic implant placement in horses has been reported but not compared with respect to specific antibiotic protocols administered. OBJECTIVES: To determine factors associated with SSI in horses undergoing proximal interphalangeal joint (PIPJ) arthrodesis including perioperative antibiotic protocols. METHODS: Records were evaluated (2010-2019), and horses undergoing PIPJ arthrodesis were identified. Patient signalment, supervising surgeon, reason for surgery, limb, implants placed, anaesthetic time, duration casting/coaptation postoperatively, antibiotic regimen and incidence/onset SSI were recorded. Bayesian and frequentist logistic regressions were used to estimate the contribution of covariates to infection occurrence. RESULTS: Fifty-four PIPJ arthrodeses were performed. SSI occurred in 2/54 (3.7%) on day 15,30. Arthrodesis was performed most commonly for osteoarthritis (33/54, 61.1%), fracture (11/54, 20.4%), and subluxation (5/54, 9.3%). Perioperative systemic antibiotics were administered 1-3 days (15/54, 27.8%) or > 3 days (39/54, 72.2%). Antibiotic protocols included cefazolin/gentamicin (20/54, 37%), cefazolin/gentamicin/doxycycline (14/54, 25.9%) and potassium penicillin/gentamicin (10/54, 18.5%). Regional limb perfusion was performed preoperatively 31/54 (57.4%) and postoperatively 7/54 (13%). Survival to dismissal was 98.1% (53/54 horses) with one horse euthanized due to support limb laminitis. No association was identified between antibiotic selection or duration (1-3 vs. > 3 days), pre-operative regional antibiotic perfusion, intraoperative antibiotic lavage or anaesthetic time (< or > 3 h) and SSI; however, modelling was complicated by quasi-complete or complete separation of the data. Bayesian analysis (but not frequentist analysis) indicated an association between post-operative regional antibiotic perfusion and SSI. Limitations include the retrospective nature of data collection and the low rate of infection overall. CONCLUSIONS: The prevalence of SSI in this population was lower than that in previous reports of equine orthopaedic internal fixation. There was no difference in SSI rate in cases administered systemic antibiotics for 1-3 days or >3 days, or for those horses that did or did not receive preoperative regional antibiotic perfusion.

Clinical and Radiologic Results of a Human Bone Graft Screw in Tarsometatarsal II/+III Arthrodesis.

BACKGROUND: For arthrodesis of the tarsometatarsal joints, there is the possibility of using a transplant screw made of allogenic human bone material (Shark Screw). This article investigates the clinical outcome and radiologic integration of the allogenic bone screw for arthrodesis of the tarsometatarsal joints II/+III. METHODS: This is a prospective study involving 20 feet of 17 patients who received TMT II/+III arthrodesis with an allogenic bone screw. A visual analog scale (VAS pain and function), Foot Function Index (FFI), American Orthopaedic Foot & Ankle Society (AOFAS) midfoot score, and Foot and Ankle Outcome Score (FAOS) were used as measures to compare preoperative with postoperative results. Radiologic integration in the recipient bone was also evaluated. RESULTS: A significant mean pre- to postoperative improvement of all evaluated scores has been observed (P < .05) after a mean follow-up of 15.87 months (minimum 12 months, maximum 33 months). VAS score (pain) decreased from 7.6 to 1.4 points as well as a decrease of the VAS (function) from 7.25 to 1.8 points. Further, a reduction of the FFI from 62.3% to 16.7% and an increase from 29.7 to 79.9 points of the AOFAS was detected. Analyzing the FAOS score, in all surveyed subscales, there was an increase in the score (Symptoms: 55.2 to 85.6 points; Pain: 30.5 to 86.9 points; Function: 33.1 to 88.3 points; Quality of life: 27.8 to 79.7 points). Moreover, in all cases, a complete radiologic integration into the receiving bone was appreciated, and after a minimum follow-up time from 12 months, the screw in 19 feet (95%) was no longer distinguishable from the original bone. CONCLUSION: With these first results of the allogenic bone screw in TMT II/+III arthrodesis, a significant improvement from preoperative to postoperative was confirmed in the collected scores, and a full radiographic integration was demonstrated in all feet.