University of Pennsylvania Kennett Square, Pennsylvania
Femoral fractures, common in calves post-dystocia, present fixation challenges due to poor proximal access and low bone density. The external fixator intramedullary (ESF/IM) pin tie-in is used in small animal orthopedics. Our objective was to describe outcomes and complications associated with ESF/IM pin tie-in for calf diaphyseal/metaphyseal femoral fracture fixation. Medical records were reviewed. Fractures were repaired using open reduction and fixation. An intramedullary Steinman pin was placed retrograde, the fracture was reduced, and the pin was driven distally. Transfixation pins were placed spanning the fracture site, in two cases transarticularly. After closure, 1” tubing was attached to the transfixation pins and proximal IM pin, then filled with polymethylmethacrylate. Ten calves were included. Short-term survival was 7/10 (70%). Post-operative complications included transfixation pin lucency (6/10), lameness (6/10), and fever (5/10). Transfixation pin breakage, septic arthritis, pneumonia, and anaesthetic complications had grave prognoses; transfixation pin lucency and lameness, while occurring most frequently, had good short-term outcomes (5/6, 83% survival). Short oblique and mid-diaphyseal fractures had excellent outcomes (4/4, 100% survival), while distal diaphyseal fractures had fair outcomes (4/7, 57% survival). 3/5 cases with follow-up survived long-term (>1 year). Short-term survival was comparable to previous reports. Distal fracture success rate was higher than previously reported. Limitations of this study include the small sample size and incomplete follow-up. The ESF/IM pin tie-in is less expensive than internal fixation and easily customized. Despite frequent infections, mortality remained similar to other techniques, suggesting it may be a useful and economic alternative.
