To investigate the proprioceptive function of patients with an ACL rupture before and after reconstruction and correlate these findings with ligament laxity testing and clinical outcome measures. Fifty patients with an ACL rupture and 50 normal controls were recruited to the study. The Biodex Balance SD System was used to assess knee proprioception. This equipment measures proprioceptive function using an electronic platform. The balance of the subject is computed using stabilometry and an Overall Stability Index (OSI) is produced. A lower score reflects better proprioception. Knee stability was assessed clinically and with the Rolimeter knee arthrometer in all subjects. Participants were evaluated using the Tegner, Lysholm, Cincinnati and IKDC scoring systems. In the ACL group, 34 patients underwent ACL reconstruction and returned for their follow-up review 3 months post-operatively. The proprioceptive function of the injured knee of the ACL group (mean OSI 0.70) was significantly poorer compared to that of their uninjured knee (mean OSI 0.46, p<0.001, 95%CI 0.14, 0.34) and to the Normal Control group (mean OSI 0.49, p=0.01, 95%CI 0.05, 0.38). There was a significant improvement in proprioception of the injured knee following ACL reconstruction (mean OSI 0.47, p=0.003, 95%CI 0.10, 0.42). A significant correlation was found between pre-operative proprioception measurements and all the pre-operative knee outcome scores, however this correlation was not found post-operatively. No correlation was found between ligament laxity testing and either proprioception measurements or knee outcome scores.Purpose of Study
Summary of Methods and Results
Anterior knee pain due to dysplasia of the extensor mechanism is common. We have studied 137 knees (103 patients) in order to identify a rapid and reproducible radiological feature which would indicate the need for further analysis. Overall, 67 knees (49%) had at least one radiological abnormality; 70 (51%) were considered normal. There were five cases of Dejour type-3 dysplasia of the femoral trochlea, nine of type-2 and 12 of type-1. There were 49 cases of patella alta and five of patella infera. Four knees had an abnormal lateral patellofemoral angle (patellar tilt), and in 15 knees there was more than one abnormality. Classification of trochlear dysplasia was difficult and showed poor reproducibility. This was also true for the measurement of the lateral patellofemoral angle. Patellar height was more easily measured but took time. The sulcus angle is an easily and rapidly measurable feature which was reproducible and was closely related to other features of dysplasia of the extensor mechanism. The finding of a normal sulcus angle suggested that seeking other radiological evidence of malalignment of the extensor mechanism was unlikely to reveal additional useful information. The severity of other features of dysplasia of the extensor mechanism correlated with increasing sulcus angle.
