Anterior cruciate ligament reconstruction (ACLR) using hamstring tendon (HT) graft aims to stabilise the knee, but it may bring some complications like anterior knee (AKP) pain that can have consequences on the functional aspect of this surgery. The aim of this study was to compare isokinetic knee strength and functional outcomes between patients with and without AKP following an ACLR using HT graft during the first-year post-surgery. Three hundred and thirty subjects operated by ACLR using hamstring tendon graft were included in our retrospective cohort and divided into two groups: a group with AKP (AKP+ group) and one without AKP (AKP–group). In our population, 14.8% of the patients had AKP. At 4 post-operative months, subjects with pain had lower isokinetic strength limb symmetry index (LSI) for knee flexors and extensors, and a lower Lysholm score than subjects without pain (p < 0.0001). These differences did not persist at 7 post-operative months, and there was no difference in the one-leg hop test. After multivariate analysis, we highlighted the impact of time on the evolution of these parameters. Yet, the exact definition of AKP after ACLR remains to be clearly defined since an imprecise diagnosis may lead to inappropriate management. Pre-operative information about this type of complication, which evolves favourably with time, could be useful for patients. Indeed, AKP can occur after ACLR, even if a HT graft has been used, compared to other surgical procedures using the knee extensor apparatus as patellar tendon graft (AKP is associated with the donor site morbidity). In case of AKP after ACLR, monitoring the muscle inhibition by isokinetic tests may enable clinicians to adapt the retraining and the return to sport.

Patellar tendinopathy (PT) in professional volleyball players can have an impact on their careers. We evaluated the impact of this pathology in this specific population in terms of isokinetic strength and jumping performances. Thirty-six professional male volleyball players (mean age: 24.8 ± 5.2) performed isokinetic knee assessments, single-leg countermovement jumps and one leg hop test. They filled out the Victorian Institute of Sport Assessment-Patella (VISA-P) score. Two groups were assessed: “PT group” (n = 15) and “control group” (n = 21). The VISA-P score was lower in the PT group (p < 0.0001). No difference was found between the isokinetic strength limb symmetry index and the jump performance limb symmetry index. The healthy legs of the control group were compared with the affected (PT+) and the unaffected legs (PT−) of the PT group. Compared with the healthy legs, both PT+ and PT− legs showed decreased values of quadriceps and hamstring strengths. Only PT+ legs scored lower than healthy legs in countermovement jumps and hop tests. No differences were found between PT+ and PT− legs for muscle strengths and jumps. A low correlation existed between quadriceps strength and jumping performances (r > 0.3; p < 0.001). Volleyball players with PT showed a decrease in the isokinetic knee strength. This strength deficit was found both on the symptomatic legs and the asymptomatic ones. Jumps were only significantly altered on the pathological legs. Highlighting that the unaffected limbs were also impaired in addition to the affected limbs may help provide a better adaptation of the rehabilitation management.