Tarsal tunnel syndrome is a painful entrapment neuropathy involving the posterior tibial nerve as it enters the foot. The term entrapment neuropathy denotes injury to a nerve from an external source. Examples of an entrapment neuropathy could include sciatica symptoms of low back pain originating from an injured disc in the back region that is putting pressure on the nerve root from the spinal cord. Another example would include carpal tunnel syndrome which is hand and wrist pain associated oftentimes with overuse leading to inflammation of the nerves at the wrist level.
Tarsal tunnel, like carpal tunnel is pain associated with abnormal function of the posterior tibial nerve as it enters the foot. Symptoms associated with tarsal tunnel syndrome include pain with descriptions of “knife like”, “sharp lancinating” or “numbness” involving the inside ankle and the bottom of the foot. Limited pain in the morning with intensified presentation during the day’s activity.
Causes of tarsal tunnel are diverse, including; abnormal pressure placed on the nerve from scar tissue occurring from direct nerve trauma, varicose veins, soft tissue masses, thickening of the small muscles of the foot at the region of the tarsal tunnel and biomechanical instability including abnormal foot pronation.
Tarsal tunnel oftentimes is found in conjunction with a form of heel pain called plantar fascitis. Treatment for tarsal tunnel includes the use of anti-inflammatory medications like ibuprofen and ice, as well as the use of shoe and orthotic therapy to decrease the mechanical load on the inflamed nerve. Occasional use of cast boots to increase the ankle motion and stress may be required. The clinical course of tarsal tunnel syndrome can be unpredictable despite treatment and can occasionally advance to surgical care.