That’s a good question and one that has been asked by many patients and surgeons alike. In fact, many studies have already been done on this topic. Researchers have been trying for years to figure out just when, how, and why immobilizers should be used after an anterior cruciate ligament (ACL) repair or reconstruction.
Part of the problem in coming to a definite answer lies in the fact that there are all kinds of knee immobilizers and braces. They can be worn for different periods of time and for different reasons. Some surgeons use them to protect the healing graft. Others use them to help control pain. With different variables measured from study to study, it’s difficult to come up with a firm conclusion about immobilizing the knee after ACL repair.
In a recent study from Canada, two groups of patients with ACL repair were compared. One group wore a soft, unhinged knee immobilizer for two weeks after the surgical procedure. The second group did not wear an immobilizer. The main measure of brace effectiveness was pain in the first two days after surgery.
The researchers also took a look at how much (and what kind) of pain relievers were used during the first two days up to the first two weeks after surgery. They didn’t find any differences between the two groups. They came to the conclusion that at least for pain control after ACL repairs with a hamstring graft, an unhinged knee immobilizer isn’t needed postoperatively.
It’s possible that some other type of immobilization would be more effective. Perhaps using a hinged knee brace would appeal to patients more and improve compliance. The authors suggested trying a hinged knee brace in a future study. Patients could lock it at night to protect joint motion and wear it hinged during the day to allow motion.
Since the group that wasn’t immobilized at all had the same results, it’s logical to conclude immobilization has no added benefit when used for pain control. Other studies are needed to address concerns about the need for bracing postoperatively for other reasons such as knee stability or graft protection.