Summary
At 5 years after ACLR, operated leg functional performance is equal to that of the non-operated leg; however, kinesiophobia is present in nearly half of patients.
Abstract
Background
Psychological and physiological factors could negatively affect patients' recovery and increase re-injury rate after anterior cruciate ligament reconstruction (ACLR). In daily practice, surgeons and physiotherapists see athletes struggling to improve muscle strength and complaining of a lack of self-confidence during their progress to return to sport. The Tampa Scale for Kinesiophobia is a valid questionnaire to measure a patient's psychological status, and an isokinetic test is widely used to measure muscle recovery.
Hypothesis
Patients with kinesiophobia have inferior self-reported and functional outcomes after ACLR.
Methods
140 patients – 100 (71%) men and 40 (29%) women, mean age 32.5 (±8.3 ) – were included in the study 5.5 (±1.25) years after ACLR. All patients were operated by two senior surgeons. Preoperative and postoperative assessments were performed by two sports-specialized physical therapists. Patients completed the Knee injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score and Tampa Scale of Kinesiophobia (TSK-17) questionaires. Quadriceps and hamstring muscle isokinetic strength was assessed at 60°/sec and 180°/sec using the HumacNorm dynamometer. Functional performance was tested with the single-leg hop test for distance and the Y-balance test for anterior reach. Variables of the study were described by means and standard deviations. A Shapiro–Wilk test was conducted to test for normality of the variables, and unpaired t-tests were used to test for differences between subgroups. After tests were conducted, simple Bonferroni adjustment was applied to account for the number of tests made.
Results
68/140 patients (48.6%) reported a TSK-17 score equal to or higher than 37 points, above which is the cut-off score for kinesiophobia.
Patients with kinesiophobia had statistically significantly lower KOOS Symptoms (p = 0.001) and Quality of Life subscores (p = 0.001), Total score (p = 0.001) and Oxford Knee Score (p = 0.024).
Isokinetic peak torque muscle strength mean deficits at 60°/sec and 180°/sec for knee flexion and extension were between 6% and 7% for patients with kinesiophobia, and they were between 2% to 4% for patients without kinesiophobia compared with the contralateral side, with no significant differences between groups.
There was no statistically significant difference in the single-leg hop test for distance mean leg ratio (0.98 (±0.19) and 1.00 (±0.26)) or the Y-balance test for anterior reach mean leg ratio (0.99 (±0.08) and 1.01 (±0.07)), respectively, between the groups.
Conclusion
At 5 years after ACLR, operated leg functional performance is equal to that of the non-operated leg. However, kinesiophobia is present in nearly half of patients. Strength and functional tests alone are not good enough instruments for assessing complete recovery; on the other hand, self-reported questionnaire scores show a high correlation with kinesiophobia after ACLR. Further studies are needed to help in avoiding development of kinesiophobia, as well as recognizing the phobia at early stages of rehabilitation.