The Analysis of Proprioception Alteration during First Five Months after Anterior Cruciate Ligament Reconstruction

Abstract

Research  background  and  hypothesis.  Proprioception  is  important  in  the  prevention  of  injuries  as  reduced
proprioception  is  one  of  the  factors  contributing  to  injury  in  the  knee  joint,  particularly  the  ACL.  Therefore,
proprioception appears not only important for the prevention of ACL injuries, but also for regaining full function
after ACL reconstruction.
Research aim. The aim of this study was to understand how proprioception is recovered four and five months
after anterior cruciate ligament (ACL) reconstruction.
Research methods. The study included 15 male subjects (age – 33.7 ± 2.49 years) who had undergone unilateral
ACL reconstruction with a semitendinosus/gracilis (STG) graft in Kaunas Clinical Hospital. For proprioceptive
assessment, joint position sense (JPS) was measured on both legs using an isokinetic dynamometer (Biodex), at
knee flexion of 60° and 70°, and at different knee angular velocities of 2°/s and 10°/s. The patients were assessed
preoperatively and after 4 and 5 months, postoperatively.
Research results. Our study has shown that the JPS’s (joint position sense) error scores  to a controlled active
movement is significantly higher in injured ACL-deficient knee than in the contralateral knee (normal knee) before
surgery and after four and five months of rehabilitation.  
After 4 and 5 months of rehabilitation we found significantly lower values in injured knees compared to the
preoperative data. Our study has shown that in injured knee active angle reproduction errors after 4 and 5 months of
rehabilitation were higher compared with the ones of the uninjured knee. Proprioceptive ability on the both legs was  
independent of all differences angles for target and starting position for movement. The knee joint position sense on
both legs depends upon the rate of two different angular velocities and the mean active angle reproduction errors at
the test of angular velocity slow speed was the highest compared with the fast angular velocity.
Discussion and conclusions. In conclusion, our study shows that there was improvement in mean JPS 4 and 5
months after ACL reconstruction, but it did not return to normal indices.

Keywords: knee joint, joint position sense, angular velocity, starting position for movement.