Striking the likes of Chicago Bulls¹ Derrick Rose, L.A.
Lakers¹ Kobe Bryant and Detroit Tigers¹ Victor Martinez, tears in the
anterior cruciate ligament (ACL) are one of the most rampant and serious
knee injuries among athletes.
Now, researchers from the University of Michigan Health System have
identified a new drug target that may prevent one of the most dreaded
consequences of an ACL tear the weakening or loss of muscle tissue (muscle
atrophy) that can be a career-killer in sports and ultimately develop into
A hormone called myostatin that blocks muscle growth appears to play a key
role in causing muscle damage after ACL tears, according to a study that
appears in the American Journal of Sports Medicine. The findings pave the
way for potential treatment preventing muscle loss after an ACL tear and
consequent knee replacement, which affects more than 250,000 people a year
in the U.S.
³We¹ve had several advances in technology to improve the recovery process
for an ACL tear, but most patients still experience 30-40 percent muscle
weakness and that weakness largely limits the ability to return to the
same level of sports,² says lead author and athletic trainer Christopher L.
Mendias, Ph.D., A.T.C, assistant professor of Orthopaedic Surgery and
Molecular & Integrative Physiology at the U-M Medical School.
³This is the first study in humans to open the door to a potential therapy
to prevent muscle atrophy. We see this as an important step in restoring
athletic and functional abilities in the short term, and in preventing
osteoarthritis in the long term.²
Often dubbed an athlete¹s worst nightmare, ACL tears usually require
surgical repairs and months of intense rehabilitation that force long breaks
from playing any sports.
Myostatin has shown promise as a potential drug target for treating other
conditions such as muscular dystrophy and cancer, and blocking the protein
has led to increased muscle mass and strength.
³In the sports world, there¹s great concern about the short-term and
long-term affect of an ACL tear on not only an athlete¹s physical skills and
ability to return to play, but also the longevity and health of the knee
joint,² says senior author Asheesh Bedi, M.D., assistant professor in
³This is the first study to look into the biology of muscle tissue involved
in an ACL tear and to show how Myostatin affects the muscle damage we see
following surgery. We need further studies to examine how these findings may
aid in better recoveries following a common and often detrimental type of
knee injury for athletes.²