Baxter first described this condition in 1984. Baxter proposed that the first branch of the lateral plantar branch of the posterior tibial nerve would become entrapped in the medial heel. The entrapment would result in heel pain and numbness of the plantar aspect (bottom) of the heel.

Diagnosing Baxter's nerve entrapment requires a high degree of clinical suspicion. Clinical testing as described below (Phalen's maneuver and abductor digiti minimi testing) is not considered to be a definitive or conclusive set of tests. MRI's, nerve conduction studies and EMG studies are also limited in their ability to 'rule in' a diagnosis of Baxter's entrapment.

Treatment

Conservative treatment of Baxter's entrapment is limited. Some advocate the use of oral or injectable steroids. Orthotics may be helpful to control contributing biomechanical issues such as pronation.

Surgical release of the nerve, called external neurolysis, is the preferred method of care. The procedure is completed in a surgery center or hospital setting. External neurolysis of Baxter's nerve may be performed with a local anesthetic and sedation or with a general anesthetic. The goal of neurolysis is to identify the physical irritation or the nerve, release those strictures and allow the nerve to return to normal function. Recovery varies but typical neurolysis cases do require a period of non-weight bearing on crutches.

Other methods of treatment described in the literature include cryosurgical neurolysis, chemical neurolysis and radiofrequency ablation.  Each of these methods use cold, chemicals or heat to ablate, or destroy Baxter's nerve.  The literature does not discuss comparative success rates of these methods compared to traditional surgical neurolysis.  When comparing the safety and efficacy of each of these methods of care, you must remember that surgical neurolysis is a nerve sparing surgery where as cryo, chemical and radio frequency ablation is a nerve destructive procedure.  Therefore patients who are considering one of these methods of treating a Baxter's nerve entrapment should discussed the pros and cons of each of these methods with their doctor prior to surgery.

Due to the fact that Baxter's nerve entrapment is commonly found in conjunction with plantar fasciitis, a plantar fasciotomy is often perform in addition to neurolysis.  And for sake of clarity, surgical external neurolysis is a surgical release of one of the three branches of the posterior tibial nerve.  Surgeons will often perform a release of all three branches of the posterior tibial nerve during the course of surgery.  When all three branches are released, this procedure is called a tarsal tunnel release.  Tarsal tunnel releases are often used to treat tarsal tunnel syndrome.  Doctors will often refer to a Baxter's nerve entrapment as a partial tarsal tunnel, suggesting and isolated entrapment of the calcaneal branch of the posterior tibial nerve.