A new treatment has been proposed for tennis elbow also known as lateral epicondylitis. Pain along the outside (lateral) elbow from chronic overuse and repetitive activities can be ended by interrupting the nerve pathways. In this study, a partial nerve denervation was tested as a possible alternative to the more common treatment approaches.
By cutting the tiny nerve branches to the lateral epicondyle (side of the elbow away from the body), the authors hoped to provide pain relief without altering elbow function. They used pain and grip strength as their main tests of treatment effectiveness.
Thirty elbows were included in this study. All patients had tried more than six months of conservative (nonoperative) care without success. They took antiinflammatory medications. They tried bracing and physical therapy. They had at least one cortisone shot into the tendon at fault. Nothing changed their pain significantly enough to be considered effective.
The reason chronic tennis elbow doesn’t get better sometimes is because the tiny microtears of the extensor tendons that are involved don’t heal fully. A partial repair gets interrupted and ends in distortion of the collagen fibers and degeneration of the tendon fibers. Many microscopic studies have proven there is a lack of actual inflammation in these chronic cases.
Many times when nonoperative treatment fails, surgery to release the tendon from its attachment to the bone is suggested. But in this study, hand surgeons tried a different approach. They used a small open incision to carefully identify the tiny nerve branch to the lateral elbow, injected it with a numbing agent, and then cut it. They moved the nerve branch up into the main belly of the triceps muscle (along the back of the upper arm) where it could not reconnect or cause any further pain.
Before trying this approach, each of these patients did respond well with pain relief and improved grip strength to a temporary diagnostic nerve block. The specific area numbed (and later cut) was the posterior cutaneous nerve of the forearm just above the lateral humeral epicondyle (outside of the elbow bone). None of the patients had any previous elbow surgery or nerve blocks before this study.
Everyone was followed for at least two years. Early follow-up included assessment of pain and testing grip strength. Final follow-up was done using an emailed survey of pain and level of patient satisfaction. Each patient contacted was also asked if they would have this same type of (denervation) surgery if the other elbow developed chronic tendonitis.
As it turned out, 80 per cent of the group reported good to excellent results with pain relief and improved grip strength. The treatment was considered a “failure” if the patient still had significant persistent pain and/or had to have another surgery. Because a superficial nerve (to the skin) was cut, some of the patients had numbness along the forearm for a while. This was temporary for all but one patient but no one was bothered by it because the pain was gone!
Of the five patients who had a “failed” response, four of them also had a condition known as radial tunnel syndrome. Radial tunnel syndrome happens when the radial nerve is squeezed where it passes through a tunnel near the elbow. The symptoms of radial tunnel syndrome are very similar to the symptoms of tennis elbow (lateral epicondylitis). There are very few helpful tests for radial tunnel syndrome, which can make it hard to diagnose.
It is possible that the radial tunnel syndrome is really the reason why these few patients did not respond fully to the denervation procedure. Further study of this problem is needed to determine whether additional treatment of this second problem will eliminate the painful symptoms and weakness.
But for now, this study showed that a partial denervation is a simple and effective, alternative way to treat persistent lateral epicondylitis. And it showed that using a diagnostic local numbing agent is a good way to tell who might benefit from partial denervation. Patients may prefer this partial nerve denervation treatment over epicondylectomy (to remove the damaged tendon and bone). They can get back to daily activities right away and return to work faster without the need for rehab.