Users of functional knee braces and neoprene sleeves have similar recoveries from anterior cruciate ligament (ACL) reconstruction, according to new research presented at the 2007 Annual Meeting of the American Orthopaedic Society for Sports Medicine at the Telus Convention Center (July 12-15).
"For patients returning to sport after ACL reconstruction, a functional knee brace, which is sturdy, elaborate, and expensive, does not provide advantages over a soft neoprene elastic sleeve," says principal investigator Trevor Birmingham, Ph.D., P.T., Canada Research Chair in musculoskeletal rehabilitation at the University of Western Ontario and the Fowler Kennedy Sport Medicine Clinic in London, Ontario.
ACL reconstruction surgery is common, particularly in young, athletic individuals. The ACL is an important ligament inside the knee that helps keep it stable. ACL reconstruction involves replacing the torn ACL with a strip of tendon called a graft. Approximately 100,000 ACL reconstructions are performed annually according to the American Academy of Orthopaedic Surgeons.
"It is widely believed that the rigid support provided by a functional knee brace protects the graft and improves knee stability and function when the patient returns to sport after surgery and rehabilitation," explains Dr. Birmingham. "Others believe that the additional support provided by a brace is not necessary."
To address this uncertainty, Dr. Birmingham and colleagues studied 150 athletes preparing to return to sport following ACL reconstruction. Seventy-six patients were randomized to receive a functional knee brace and 74 to receive a neoprene sleeve. The patients were instructed to wear the orthosis during all physical activities. The researchers found no significant differences between the groups at the one- and two-year follow-up visits.
"Based on our clinical experience, we were not completely surprised by the results," Dr. Birmingham comments. "These findings provide strong evidence that the average patient does not require a functional knee brace when returning to sport after ACL reconstruction. There may be some patients who will benefit from a brace, and identifying these individuals requires further research. Until then, these decisions are left to the surgeon's discretion."
ACL functional knee braces are made by several different companies and have a variety of looks and fitting instructions. They are intended to limit abnormal movement of the knee and prevent excessive strain on the ACL or new graft. They generally provide a rigid support to restrain the knee, although they may also improve neuromuscular control of the knee. Most laboratory studies suggest that different types of functional knee braces perform similarly.
Neoprene sleeves are also made by several different companies and have different looks. Rather than providing rigid support, they are only intended to gently compress the area around the knee and improve neuromuscular control.
The study was large enough and had enough statistical power to detect even slight differences between the functional knee brace and sleeve groups. "We can be confident that even if small but true differences between these groups exist, these differences are not large enough to be clinically important," concludes Dr. Birmingham. He notes that the study was not designed to test whether using a neoprene sleeve was better than using nothing at all.