Effectiveness of modified Arrowhead Intramedullary Pinning technique for stabilizing distal femoral fractures in cats

Abstract

Distal femoral fractures (DFF) are frequent in growing cats, representing orthopedic challenges due to anatomical instability and high biomechanical requirements. The distal metaphyseal fractures area requires better stabilization methods than the current standard techniques because they fail to provide adequate rotational support. The study evaluated the clinico-biological efficacy of a modified Arrowhead Intramedullary Pinning (AIP) technique for fracture stabilization with functional recovery. Nine growing cats with distal femoral fractures were corrected with modified AIP. The longitudinal clinical and radiographic outcomes were assessed up to 90 days. A linear mixed-effects model (LMEM) analyzed the fixed effect of treatment time, controlling for the random effect of individual cat variability. The fracture healing process occurred quickly, averaging 50.4±9.5 days, results 100% favorable outcomes. Animals become functional within 5.3±2.3 days, achieving full weight-bearing capacity at Day 45 after treatment. LMEM confirmed highly significant time-dependent improvement across all parameters (p<0.001). The radiographic and pain score results showed no statistically significant differences between individual cats (p=0.27 and p=0.06, respectively). The stifle joint angles, lameness, and weight bearing score showed substantial individual cat variation at a significance level of p<0.05. The AIP technique provides standardized mechanical fixation, ensuring predictable bone healing results using LMEM. This technique enables fast pain relief, early functional onset, and predictable healing with an effective treatment for DFF in growing cats.