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Stopping Phantom Limb Pain Before It Starts with Primary TMR

    Phantom limb pain used to be a mysterious condition and for a long time was poorly understood. In recent years, advances in medicine are changing that.  Early this year, a new theory about phantom limb pain shed light on what causes it. Dr. Max Ortiz Catalan, Associate Professor at the Chalmers University of Technology and head of the Biomechatronics and Neurorehabilitation Laboratory, published a paper on “stochastic entanglement,” describing how phantom limb pain is caused by entangled neural circuitry caused after an amputation. 

    Amputee suffering from phantom limb pain, which could be stopped before it starts with primary TMR.

    Running along the same vein, primary Targeted Muscle Reinnervation (TMR) seems to be the answer to stopping or mitigating the effects of phantom pain even before it starts. Pioneered by surgeons at The Ohio State University Wexner Medical Center, primary TMR entails the rerouting of nerves cut during amputation into surrounding muscle.

    According to Dr. Ian Valerio, division chief of Burn, Wound, and Trauma at the Ohio State’s Department of Plastic and Reconstructive Surgery, the process of attaching the nerve endings to motor nerves in a nearby muscle allows the body to re-establish its neural circuitry. It gives the severed nerves something to do as opposed to being left alone to be entangled.

    Primary TMR surgery was initially developed to allow upper limb amputees to control their prosthesis better. This was how surgeons discovered that the procedure could also improve specific causes of pain. Eventually, they began using primary TMR to treat disorganized nerve endings called symptomatic neuromas or phantom limb pain.   

    In three years, surgeons at Ohio State performed 22 TMR surgeries—18 primary and four secondary—on below-the-knee (BK) amputees. None of the patients developed phantom limb pain. Only 13% of those who received primary TMR reported experiencing phantom pain six months after the surgery. Furthermore, those who underwent the procedure reportedly reduced or, in some cases, stopped the use of narcotics and other nerve-related pain medications.

    Given the results, the researchers believe that when primary TMR is done at the time of initial amputation, there is a minimal health risk. Meanwhile, recovery is similar to that of traditional amputation surgery.

    What do you think of this technique? It appears promising for sufferers of phantom limb pain. Share your thoughts with us in the comments section below.