Patellar tendon versus hamstring tendon autograft for anterior cruciate ligament rupture in adults.

Mohtadi NG, Chan DS, Dainty KN, Whelan DB. Cochrane Database Syst Rev. 2011 Sep 7;9:CD005960.

It can be a challenge to keep track of the current research, especially if there’s conflicting findings on a topic. Subtle details, like the age or level of physical activity of the study sample, can account for differences between studies. It can be frustrating but also informative to sit back and dissect why something happened in one study but not another. To help us interpret the current evidence we can search for systematic reviews and meta-analyses on topics. Systematic reviews involve a methodical and extensive search of the literature and try to summarize the evidence (they are called a meta-analysis when statistical methods are used to develop a summary). For example, while patellar tendon and hamstring autografts are both commonly used in anterior cruciate ligament reconstructions there is no consensus on whether one if better than the other. Therefore, Mohtadi et al. conducted a meta-analysis to compare patellar tendon and hamstring autografts. After conducting a thorough search, the authors identified 19 clinical trials (1597 skeletally mature patients) comparing the outcomes over 2 years after surgery between the two ACL grafts. Overall, the authors concluded that graft selection did not influence functional outcomes (e.g., single hop test), return to play, physical activity level, subjective measures of outcomes (e.g., knee symptoms), and rate of re-ruptures. The authors noted that the data was not sufficient to assess long-term outcomes; for example, osteoarthritis. Various testing methods demonstrated that the patellar tendon reconstruction resulted in more static stability than the hamstring graft. However, patellar tendon reconstructions were also associated with more anterior knee problems and less extension range of motion. In contrast, hamstring autografts were related to a loss of knee flexion strength. The authors concluded that “the current evidence was insufficient to recommend which of the two types of grafts was better for ACL reconstruction.” Click here to see a publically available summary of the meta-analysis (includes a plain language summary).

Systematic reviews are a convenient method for summarizing the current literature. For example, this systematic review reported pros and cons of both grafts when compared head-to-head. Systematic reviews can be found via PubMed, Clinical Queries, The Cochrane Library, PEDro, and several other online sources (please let us know if you have a favorite database!). However, it is important to keep in mind that systematic reviews and meta-analyses are not the final answer. These reviews may be biased by the search strategy, the inclusion criteria for articles, and many other factors. Furthermore, it is important to keep in mind that a systematic review reports the typical finding among studies. Therefore, the optimal treatment (e.g., graft) might not be the right choice for your patient. Although, some of the secondary analyses might help you figure out what might be the best choice for your patient. As sports medicine research quickly advances, systematic reviews and position statements will be important ways of keeping informed, but we can’t blindly accept their findings. At the end of the day it’s up to the clinician and the patient to make the decision about the best treatment. Share your thoughts on how you’re keeping up with the immense amount of research coming out each month.

Written by: Jeffrey Driban
Reviewed by: Stephen Thomas