Description
Objectives: To evaluate the difference in extension and flexion strength in Isokinetic testing and its ratio between pre-surgery and 12 months
postoperatively using QTA compared to STA.
Methods: This is a randomized controlled trial, in which 40 participants, all of them soccer players were included, divided into two groups according to the
autografts applied: QTA (N=20) or STA (N=20). The knee flexor and extensor strength with the isokinetic dynamometer were tested at three different
speeds: 300o/s, 180o/s and 60o/s, both pre-surgery and at 12 months. Student's t-test or its non-parametric counterpart in SPSS software was used and a
significance level of p<0.05 was established.
Results: There were no differences between groups in either flexion or extension strength in any of the tests. Three patients in the STA group and two
patients in the QTA had graft rupture before the one-year follow-up. Intragroup differences suggested a significant recovery at 300o/s velocity both in
flexors and extensors only in STA group (that is an improvement in isokinetic strength of 34.67 ± 7.64 N and 20.67±7.16 N from baseline, respectively).
Similarly, both groups improved significantly flexors strength at 180o/s and also at 60o/s compared to baseline values. However, the strength gain of the
extensor muscles was significantly higher in the STA group at the 180°/s and 60°/s speeds (36.89 ± 9.01 and 52.44 ± 12.99, respectively).
Conclusions: Individual intra-group measures indicate that the STA group significantly recovers muscle strength in both flexors and extensors at the three
speeds tested, representing improvements in maximal strength, endurance and fatigue resistance values. The QTA has a less striking strength recovery,
but based on our results it has a lower rate of re-rupture compared to STA.
