An Anterior Cruciate Ligament reconstruction is a very effective procedure that can put right years of punishment on the knee, but there’s a downside – people who have undergone ACL reconstruction often face bone and muscle loss immediately following the procedure, due to enforced inactivity and other factors.
However, research from the Houston Methodist Hospital which was published last month points towards a solution: a combination of blood flow restriction (BFR) therapy and traditional rehabilitation efforts, geared towards slowing bone loss and reducing return-to-function time.
The study involved 23 active and young patients (with an average age of 23) who had undergone ACL reconstruction, who were put into two groups. While both groups received the same rehab protocol, one group received BFR therapy: namely, they exercised with an 80% arterial limb occlusion using an automated tourniquet.
What is blood flow restriction therapy?
BFR therapy does pretty much what it says on the tin: a surgical tourniquet system which resembles a blood pressure cuff is applied to an injured arm or leg, which temporarily reduces blood flow to the limb while the patient exercises. The reason for this is to allow the patient to work the muscles without the risk of putting excessive weight on the limb in question while activating the muscles on that limb. It’s a relatively new method – one which has its supporters and detractors.
After both groups were measured for bone mineral density, bone mass, and lean muscle mass, the research team concluded that the addition of BFR therapy to standard rehab exercises was found to prevent muscle mass loss in the whole leg and thigh in the post-operative limb compared to rehab alone. Not only that, but the addition of BFR also appeared to minimise losses in bone mineral content and preserve bone density in the limb compared to standard rehab alone.
Tied to be fit
“Providing BFR as part of the rehabilitation efforts following ACL surgery appears to help preserve the bone, recover muscle loss and improve function quicker, according to our research,” said Bradley Lambert, the lead researcher. “BFR is a suitable additive therapy to ACL rehabilitation for the purposes of minimizing the loss, and enhancing the recovery of muscle, bone, and physical function.
“While further research is needed to fully illuminate the physiologic mechanisms responsible for our results, these findings likely have wide-ranging implications for fields outside of ACL rehab alone such as injury prevention, age-related muscle and bone loss, military rehabilitation, and potentially space flight,” said Lambert.
We have known about the effects of blood flow restriction as a means of improving muscle recovery for a while now – particularly in situations where the joint cannot be loaded heavily as it heals. But the idea that the technique can make an improvement in the bone mineral density recovery is a new revelation and definitely worth looking into further.
The downside of BFR is that it’s heavily reliant on outside help and is only usually available in a professional setting – but if you’re in rehab and the technique is available to you, it’s definitely worth taking up with your support system.