Exercise for treating isolated anterior cruciate ligament injuries in adults

The anterior cruciate ligament (ACL) is the most frequently injured ligament of the knee. Injury causes pain, effusion and inflammation leading to the inability to fully activate the thigh muscles. Regaining muscular control is essential if the individual wishes to return to pre-injury level of function and patients will invariably be referred for rehabilitation.

To present the best evidence for effectiveness of exercise used in the rehabilitation of isolated ACL injuries in adults, on return to work and pre-injury levels of activity.

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PEDro - The Physiotherapy Evidence Database, CINAHL, AMED, and reference lists of articles.

Randomised controlled trials and quasi-randomised trials testing exercise programmes designed to rehabilitate adults with isolated ACL injuries. Trials where participants were randomised to receive any combination of the following: no care, usual care, a single-exercise intervention, and multiple-exercise interventions. The primary outcome measures of interest were returning to work and return to pre-injury level of activity post treatment, at six months and one year.

All trials judged to have met the inclusion criteria were independently assessed for methodological quality by use of a 15 point checklist. Pairs of authors independently extracted data. For each study, relative risk and 95% confidence intervals were calculated for dichotomous outcomes and mean differences and 95% confidence intervals calculated for continuous outcomes.

Nine trials, involving 391 participants met the inclusion criteria of the review. Only two trials, involving 76 participants, reported conservative rehabilitation and seven trials, involving 315 participants, evaluated rehabilitation following ACL reconstruction. Methodological quality scores varied considerably across the trials, with the nature of participant and assessor blinding poorly reported. Trial comparisons fell into six categories. Pooling of data was rarely possible due to lack of appropriate data as well as the wide variety in outcome measures and time points reported. Insufficient evidence was found to support the efficacy of one exercise intervention over another.

This review has demonstrated an absence of evidence to support one form of exercise intervention against another and the use of supplementary exercises in the management of isolated ACL injuries. Further research in the form of large scale well designed randomised controlled trials with suitable outcome measures and surveillance periods, using standardised reporting should be considered.