Posterior Tarsal Tunnel Syndrome

Aka: Posterior Tarsal Tunnel Syndrome, Tarsal Tunnel, Tibial Neuropathy, Posterior Tibial Nerve Entrapment

1. Anatomy (See Ankle Anatomy)
   1. Posterior Tibial Nerve
      1. Behind medial malleolus and under flexor Retinaculum
   2. Flexor Retinaculum
      1. Arises from medial malleolus
      2. Insertion into medial Calcaneus
      3. Encases
         1. Posterior tibial nerve
         2. Tibialis posterior tendon
         3. Flexor digitorum longus tendon
         4. Flexor hallucis longus tendon
         5. Posterior tibial artery
         6. Posterior tibial vein
2. Epidemiology
   1. Uncommon
3. Pathophysiology
   1. Posterior Tibial Nerve compressed in flexor Retinaculum
4. Associated Conditions
   1. Phlebitis
   2. Rheumatoid Arthritis
   3. Pes planus
   4. FootFracture
   5. Foot traction injury
   6. Heel or foot deformity
   7. Foot mass lesion
5. Symptoms
   1. Burning, numbness, or tingling sensation
      1. Starts at plantar heel
      2. May radiate to distal sole of foot to toes
      3. May radiate to calf
   2. Provocative
      1. Worse with ambulation
      2. Worse at night
6. Signs
   1. Sensory loss in posterior tibial nerve distribution
   2. Motor function usually intact
      1. Intrinsic Muscle Weakness may be present
   3. Provocative maneuvers may elicit symptoms
      1. Tinel's sign
         1. Percussion over Tarsal Tunnel (Flexor Retinaculum)
         2. Identify posterior tibial tendon
            1. Lies behind medial malleolus
            2. Find tendon by inverting foot against resistance
         3. Posterior tibial nerve lies behind tibial tendon
      2. Stretch, compress posterior tibial nerve
         1. Simultaneous dorsiflexion and eversion of foot
7. Differential Diagnosis
   1. Complex Regional Pain Syndrome
   2. Plantar Fasciitis
   3. Diabetic Neuropathy
   4. Lumbar Disc Disease (Lumbosacral Radiculopathy)
   5. Peripheral Neuropathy
   6. Posterior tibial dysfunction
   7. Exertional Compartment Syndrome
8. Management
   1. Stretching Program
   2. Medial Heel wedge or Heel Seat
      1. Inverts heel
      2. Removes traction from tibial nerve
   3. Orthotics to correct foot Posture (e.g. pes planus)
   4. Tarsal Tunnel Injection
   5. Surgical release of entrapment
      1. Indicated for persistent symptoms
9. References
   1. Del Toro in Frontera (2002) Essentials PM&R, p. 453-6
   2. Mann in DeLee (2003) Orthopedic Sports Med, p. 2474-6
   3. Shapiro (2003) Med Clin North Am 87(3):663-96