Effects of Microselective Neurotomy on Focal Spasticity and Description of the Surgical Technique

We studied the microselective neurotomy (MSN) and its advantages to alleviate disabling spasticity. The best indication for MSN is focal spasticity. We performed 298 MSN, 87 nerves on the upper limb, 211 nerves on the lower limb) in 68 patients. The initial causes were: stroke, cranial trauma, postoperative complications and multiple sclerosis. MSN procedures were performed on the median nerve (n = 40) for wrist and finger flexion; musculo-cutaneus nerve (n = 38) for elbow flexion; ulnaris nerve (n = 9) for cubital deviation of the hand; gastrocnemius nerve (n = 98) and soleus nerve (n = 49) for equinus foot, tibial posterior nerve (n = 45) for varus foot, and fascicles (or bundles) of the flexor digitorum for “claw” toes (n = 19). The main preoperative test to identify the responsible nerve was a neuromuscular block with local anesthesia (lidocaine or bupivacaine) injected into the site of the nerve connecting the spastic muscle. During surgery, the identified nerve was exposed and its epineurium opened. Nerve bundles were teased apart into individual rootlets and a number of rootlets cut were previously planned, according to the spasticity. Follow-up was performed for up to 10 years, with a mean period of 29 months. Results demonstrated a reduction of limb spasticity of 2 to 3 points: modified Ashworth scale (MAS). Pain and clonus were also diminished in the affected limb. In some cases, voluntary movement was once again possible. MSN is a useful alternative in those cases of focal spasticity where physiotherapy and nerve block with botulinum toxin or phenol no longer produce satisfactory results.