Houston Methodist. Leading Medicine

Knee News

Hamstring Weakness after ACL Reconstruction Does Mean Squat

When the anterior cruciate ligament (ACL) in the knee tears, it usually requires surgery. The torn ACL is often removed and replaced with a tendon graft from the same leg. More and more evidence says that hamstring tendon grafts are the best way to reconstruct a torn ACL. (The hamstring is the group of muscles on the back of the thigh.) Recovery seems good, and most athletes can return to their sports. However, these doctors found some patients--those who wrestled, did gymnastics, or practiced judo--who complained that their hamstrings weren't as strong as they used to be.

So the authors decided to do more detailed tests of hamstring strength after ACL surgery. Ninety patients took part in this study. The authors divided them into two groups. One group got a tendon graft from the semitendinosus tendon of the hamstring. The other group had grafts that were taken from both the semitendinosus and the gracilis tendons. Both types of grafts are commonly used in ACL reconstruction surgery.

Thigh muscle strength and knee function was tested before surgery. The same tests were repeated at various times up to two years later. The standard tests showed good results in strength and function for both groups. However, the authors did see a difference during more in-depth testing of hamstring strength. The hamstring muscles were much weaker after surgery when the knee was deeply bent, as when squatting. The hamstring muscles that got both a semitendinosus and gracilis tendon graft were weaker than the other group. The weakness was due to the effects of taking graft material from the leg.

The authors note that both groups got good results overall. However, hamstring strength is important for knee stability and for doing certain movements. The authors believe that which graft to choose might depend on what sports the patient wants to return to. The authors are now testing whether different exercises could help strengthen the hamstring muscle after ACL reconstruction using hamstring graft tendons.

Toshiyuki Tashiro, MD, et al. Influence of Medial Hamstring Tendon Harvest on Knee Flexor Strength after Anterior Cruciate Ligament Reconstruction: A Detailed Evaluation with Comparison of Single- and Double-Tendon Harvest. In The American Journal of Sports Medicine. July/August 2003. Vol. 31. No. 4. Pp. 522-529.


*Disclaimer:* The information contained herein is compiled from a variety of sources. It may not be complete or timely. It does not cover all diseases, physical conditions, ailments or treatments. The information should NOT be used in place of visit with your healthcare provider, nor should you disregard the advice of your health care provider because of any information you read in this topic.
All content provided by eORTHOPOD® is a registered trademark of Medical Multimedia Group, L.L.C.. Content is the sole property of Medical Multimedia Group, LLC and used herein by permission.

Our Specialties

Where Does It Hurt?

Our Locations

  Follow Us

Follow us on Facebook Follow us on YouTube
Follow us on Twitter