Understanding Post-Amputation Neuroma Pain
A neuroma is a disorganized growth of nerve cells at the end of divided nerves in an amputated limb that can become painful. This disorganized growth of nerve endings forms as a result of your body’s attempt to heal.
However, when a limb is amputated, those severed nerves have nothing to regenerate to, resulting in neuroma formation.
When and Why Post-Amputation Neuromas Form
A neuroma forms after every amputation, said Dr. Gregory Dumanian, a plastic and reconstructive surgeon with Northwestern University. This happens because, in every case, the nerves are being cut and have nothing to regenerate to. But a patient’s pain from their neuroma can vary widely. It is not known why some neuromas are completely pain-free and others cause horrible pain.
“If you do a survey of amputees, 25% have absolutely no pain, 25% have mild pain, 25% have moderate pain and it's not fair but 25% have severe pain,” he said.
While there is no way to predict whether a patient will experience pain from a neuroma or the severity of that pain, Dr. Dumanian notes that if you’ve experienced a painful nerve injury in another part of your body, you may be more susceptible to pain from a neuroma.
Is it Post-Amputation Neuroma Pain or Something Else?
It can be difficult to distinguish post-amputation neuroma pain from other forms of post-amputation pain, such as pain from an ill-fitting prosthesis, soft tissue or muscular issues. There are tests your clinician can do to determine whether your pain is from neuroma or another issue. Dr. Dumanian described one test called the Tinel’s Sign.
“As the surgeon taps the skin over the neuroma and it causes both pain and a sensation in the distribution where their nerve would go,” he explained.
Another way to detect whether the pain is nerve-related is to try a nerve block. A surgeon would inject a numbing medication higher up into the nerve. If you feel more comfortable for a few hours while the numbing medicine is working, then it’s likely your pain is coming from a nerve.
Treatments for Post-Amputation Neuroma Pain
If you’re experiencing pain you’re unable to live with, you should seek treatment, said Dr. Dumanian. There are several options available, including medications, targeted muscle reinnervation (TMR) or prosthesis adjustment.
Medications like acetaminophen and ibuprofen can help control pain, as can medications like Lyrica, Gabapentin or some antidepressants. It’s important to note that opioids aren’t commonly prescribed for treating post-amputation neuroma pain.
An adjustment of your prosthesis may be needed if your pain is coming from an ill-fitting one.
And finally, a surgical procedure known as TMR can help relieve and control your pain. Created by Dr. Todd Kuiken and Dr. Dumanian, TMR reroutes the nerves severed in the amputation to nearby motor nerves. Originally intended as a procedure to help amputees better control their prosthesis, Dr. Dumanian and his team also found that TMR helps relieve neuroma pain.
How TMR Works to Relieve Post-Amputation Neuroma Pain
TMR is a surgical procedure that reroutes the severed nerves to nearby motor nerves, helping them to regenerate.
“The amputated nerve is re-routed or transferred to reinnervate a nearby muscle,” Dr. Dumanian explained. “Up until TMR, every single strategy to deaden the end of a painful nerve involved hiding the nerve in muscle or bone tissue. TMR is the first surgery that attempts to heal the nerve.”1
Despite the procedure’s success, there are times when a TMR procedure does not relieve a person’s pain.
If a person has experienced a brachial plexus injury — an injury to the nerves higher up in the neck where they exit the spinal canal — TMR is not likely to result in pain relief. And if a person has a centralized pain syndrome, TMR is not likely to provide pain relief. Patients with centralized pain syndrome have changes in the way their brains perceive pain.
“Because the brain has just gotten used to the pain, even when you treat the end of the nerve, the pain does not resolve. Luckily this seems more uncommon than common,” said Dr. Dumanian.
Regardless of the severity of your post-amputation neuroma pain, there are ways to treat it. Speak to your care team about your options, or if you’re ready to try TMR, find a surgeon who offers the procedure to help decide if this procedure is right for you.
Dumanian GA, Potter BK, Mioton LM, et al. Targeted muscle reinnervation treats neuroma and phantom pain in major limb amputees: a randomized clinical trial. Ann Surg. 2018.
TMR is not a treatment option for patients with spinal cord injuries, brachial plexus injuries, or who are generally not healthy enough for surgery. The procedure does present typical risks of surgery. Your physician will help you determine whether TMR is right for you.
Written by TMRnerve.com Staff