Causes, Diagnosis and Treatment of Heel Pain:

Tarsal tunnel syndrome occurs as a result of entrapment of the posterior tibial nerve in the tarsal tunnel where the nerve winds around the medial malleolus. It may also involve only one of its terminal branches distal to the tarsal tunnel.

Causes of Heel Pain:

In approximately 50% of cases the cause of tarsal tunnel syndrome is idiopathic. It may also occur as a result of trauma (e.g. inversion injury to the ankle) or overuse associated with excessive pronation. Other less common causes include:

• Ganglion
• Talonavicular coalition
• Varicose veins
• Synovial cyst
• Lipoma
• Accessory muscle-flexor digitorum accessories longus
• Tenosynovitis
• Fracture of the distal tibia or calcaneus.

Clinical Features:

• Poorly defined burning, tingling, or numb sensation on the plantar aspect of the foot, often radiating into the toes.
• Pain is usually aggravated by activity and relieved by rest.
• In some patients the symptoms are worse in bed at night and relieved by getting up and moving or massaging the foot.
• Swellings, varicosities, or thickenings may be found on examination around the medial ankle or heel.
• A ganglion or cyst may be palpable in the tendon sheaths around the medial ankle.
• Tenderness in the region of the tarsal tunnel is common.
• Tapping over the posterior tibial nerve may elicit the patient's pain and occasionally cause fasciculations but this ‘classic’ sign is not commonly seen.
• There may be altered sensation along the arch of the foot.
• The distribution of the sensory changes in the foot needs to be differentiated from the typical dermatomal distribution of Sl nerve root compression.

Diagnosis of Heel Pain:

Nerve conduction studies should be performed. These not only help to confirm the diagnosis but they can also guide the surgeon as to the location of the nerve compression. Ultrasound or MRI may be required to assess for a space-occupying lesion as a cause of the syndrome. An X-ray and, if required, a CT scan should be performed in the case of excessive pronation or if a tarsal coalition is suspected. Differential diagnosis includes entrapment of the medial and/or lateral plantar nerves, or both, plantar fasciitis, intervertebral disk degeneration, and other causes of nerve inflammation or degeneration.

Treatment of Heel Pain:

• Conservative treatment should be attempted in those with either an idiopathic or biomechanical cause.
• Treatment with NSAID and, if required an injection of a corticosteroid agent into the tarsal tunnel may be helpful. If excessive pronation is present, an orthosis should be utilized.
• Surgical treatment is required if there is mechanical pressure on the nerve.
• A decompression of the posterior tibial nerve and its branches should be performed, but only after both the diagnosis and site of nerve entrapment have been confirmed.
• Results of surgery have not been encouraging, with a high perioperative complication rate.