Abstract
The primary purpose of this study was to assess whether patients presenting with clinical graft laxity following primary anatomic anterior cruciate ligament (ACL) reconstruction using hamstring autograft reported a significant difference in disease-specific quality-of-life (QOL) as measured by the ACL-QOL questionnaire.
Clinical ACL graft laxity was assessed in a cohort of 1134/1436 (79%) of eligible patients using the Lachman and Pivot-shift tests pre-operatively and at 12- and 24-months following ACL reconstruction. Post-operative ACL laxity was assessed by an orthopaedic surgeon and a physical therapist who were blinded to each other's examination. If there was a discrepancy between the clinical examination findings from these two assessors, then a third impartial examiner assessed the patient to ensure a grading consensus was reached.
Patients completed the ACL-QOL questionnaire pre-operatively, and 12- and 24-months post-operatively. Descriptive statistics were used to assess patient demographics, rate of post-operative ACL graft laxity, surgical failures, and ACL-QOL scores. A Spearman rho correlation coefficient was utilised to assess the relationships between ACL-QOL scores and the Lachman and Pivot-shift tests at 24-months post-operative.
An independent t-test was used to determine if there were differences in the ACL-QOL scores of subjects who sustained a graft failure compared to the intact graft group. ACL-QOL scores and post-operative laxity were assessed using a one-way analysis of variance (ANOVA).
There were 70 graft failures (6.17%) in the 1134 patients assessed at 24-months. A total of 226 patients (19.9%) demonstrated 24-months post-operative ACL graft laxity. An isolated positive Lachman test was assessed in 146 patients (12.9%), an isolated positive Pivot-shift test was apparent in 14 patients (1.2%), and combined positive Lachman and Pivot-shift tests were assessed in 66 patients (5.8%) at 24-months post-operative.
There was a statistically significant relationship between 24-month post-operative graft laxity and ACL-QOL scores (p < 0.001). Specifically, there was a significant correlation between the ACL-QOL and the Lachman test (rho = −0.20, p < 0.001) as well as the Pivot-shift test (rho = −0.22, p < 0.001). There was no significant difference between the scores collected from the graft failure group prior to failure occurring (mean = 74.38, SD = 18.61), and the intact graft group (mean = 73.97, SD = 21.51). At 24-months post-operative, the one-way ANOVA demonstrated a statistically significant difference between the ACL-QOL scores of the no laxity group (mean = 79.1, SD = 16.9) and the combined positive Lachman and Pivot-shift group (mean = 68.5, SD = 22.9), (p = 0, mean difference = 10.6).
Two-years post ACL reconstruction, 19.9% of patients presented with clinical graft laxity. Post-operative graft laxity was significantly correlated with lower ACL-QOL scores. The difference in ACL-QOL scores for patients with an isolated positive Lachman or Pivot-shift test did not meet the threshold of a clinically meaningful difference. Patients with clinical laxity on both the Lachman and Pivot-shift tests demonstrated the lowest patient-reported ACL-QOL scores, and these results exceeded the minimal clinically important difference.
