Long-term effects of tibial angular malunion on the knee and ankle joints.
Twenty-seven patients with 28 tibial fractures were evaluated for an average of 8.2 years (range 6.0-12.3 years) following their injuries. There were 16 closed and 12 open fractures, all of which healed uneventfully. Overall, 50% of the ankles and 75% of the knees were rated good to excellent. The patients' knee and ankle joint malalignments were extrapolated using a method previously published. This was made possible by knowing both the degree and site of angular deformity. Correlation between joint malalignments and clinical outcome were performed. Analysis showed that greater degrees of ankle malalignment produce poorer clinical results (p = 0.001). Conversely, the patients with lesser degrees of ankle joint malalignment had a higher percentage of good to excellent results (p = 0.006, p = 0.003, p = 0.03). The knee results did not correlate with the degree of joint malalignment (p = 0.82). The findings in this study show that there is merit in reducing tibial fractures as close to anatomical configuration as possible to lessen the chance of early degenerative arthritis.