Is knee laxity change after ACL injury and surgery related to open kinetic chain knee extensor training load?
OBJECTIVE
The purpose of this study was to evaluate whether knee anterior laxity changes after anterior cruciate ligament injury and surgery are related to aspects of thigh muscle resistance training during rehabilitation.


METHODS
Forty-nine subjects (13 females) diagnosed with an anterior cruciate ligament-deficient knee or who had undergone anterior cruciate ligament reconstructive surgery participated in this study. The subjects trained their knee extensors in the open kinetic chain during a 6-wk program, and the relationship of aspects of training (for example, absolute resistance load) and other factors to anterior laxity change during this period were analyzed using linear regression analysis.


RESULTS
The only factor found to be significantly related (r = -0.347) to anterior knee laxity change was average absolute load used in training the knee extensors.


CONCLUSIONS
These results offer some early clinical support for increasing the strain on the anterior cruciate ligament graft (in patients treated with reconstruction) or other passive restraints to anterior tibial displacement, during rehabilitation after anterior cruciate ligament injury and reconstruction surgery to promote decreased knee anterior laxity.
Morrissey
Matthew C
MC
Division of Applied Biomedical Research, GKT School of Biomedical Sciences, King's College London, Shepherd's House, Guy's Campus, London, United Kingdom.
Perry
Mark C
MC
King
John B
JB
D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D050376:Bone-Patellar Tendon-Bone Grafting / Q000534:rehabilitation*; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000209:etiology* / Q000534:rehabilitation; D007719:Knee Joint / Q000503:physiopathology; D008297:Male; D052097:Quadriceps Muscle; D020127:Recovery of Function; D055070:Resistance Training / Q000009:adverse effects* / Q000379:methods; D055815:Young Adult