Belgian doctors researching at the University Hospital Leuven in Belgium have discovered a new ligament in the knee, the ALL (anterolateral ligament), that has long eluded classification. Their research, which was partly published in the Journal of Anatomy shows that a greater understanding of the ligament could play a key role in the surgical repair and rehabilitation of ACL injuries.
An ACL tear is a common injury that is especially prevalent in athletic sports with high demands on the knees like soccer, football, and tennis. It's usually the result of a jarring sharp twist of the knee or a powerful impact during play. The injury almost always requires surgery and physical therapy. Yet even after successful ACL surgery and rehab, some people may still experience an unsettling "pivot shift" when their knee gives way during intense physical activity.
In the past, the "pivot shift" has confused doctors, leading them to suspect that some crucial part of the equation wasn't entirely understood. The discovery of the ALL just might finally help explain why pivot shifts keep happening even after patients have gone under the knife. Orthopedic surgeons Steven Claes, M.D., and Johan Bellemans, M.D., suggest that the ALL could be the key to "internal tibial rotation," or, in other words, the ALL controls the pivoting motion of the knee, resulting in the "pivot shift."
The search for the ALL began more than a 130 years ago with the research of French surgeon Paul Segond, who described a "pearly, resistant, fibrous band" in the knee. Inspired by his findings, Claes and Bellemans began studying cadavers four years ago. They found that the mysterious ligament Segond described was present in the knees of all but one of the cadavers they investigated.
Although further research is needed, an understanding of the ALL could signal the beginning of a new age in ACL surgical repair and rehabilitation, completely revamping medical techniques and technology.