also referred to as posterior tibial neuralgia is a condition that involves compression neuropathy and a painful foot which is caused by the compression of the tibial nerve in the tarsal tunnel.
The tarsal tunnel is located behind the medial malleoluS, or the bump in the inner part of the ankle. The tunnel provides passage for the flexor hallucis longus muscles, flexor digitorum longus, tibialis posterior tendons, tibial nerve ad the tibial artery.
In the tunnel the nerve splits into 3 segments. The calcaneal, which is the nerve that goes to the heel, and the medial and lateral plantar which continue to the bottom of the foot are the three splits.
This tunnel is delineated by the flexor retinaculum on the outer part and by bone on the inner side.
Patients suffering from tarsal tunnel pain or syndrome will complain of foot numbness which radiates to the big, and the first 3 toes.
There will also be burning tingling, electrical sensation and pain. Other areas of the foot might be affected depending on the entrapment area. When the entrapment is high, the entire foot will most likely be affected because different branches of the tibial nerve will be affected.
Ankle pain has been reported by patients with high entrapment. The flexor retinaculum will have limited stretching ability and this will increase pressure that causes the nerve compression in the tunnel.
When there is pressure increase on the nerve, there will be reduced blood flow. The involved nerves will respond through numbness and tingling.
There will be fluid collection when the patient is walking or standing and this will make the condition worse. The small muscles of the foot will lose nerve supply and this will result in cramping.
Some of the symptoms that characterize tarsal tunnel syndrome include but not limited to:
1. Pain and tingling experienced around the ankle area and sometimes in the toes
2. Swollen feet Electric shock sensation.
3. A painful burning or numbing sensation experienced in the lower part of the leg. The pain will worsen with activities such as walking and standing for long durations of time and will be alleviated by rest.
4. Hot and cold sensation experienced in the feet.
5. Pain while driving.
6. A feeling as though the feet lack ample padding
7. Pins and needles sensation in the feet Pain experienced along the path of the posterior tibial nerve.
8. Burning sensation radiating from the bottom of the knee and can go up to the knee
A positive Tinel’s sign is also a symptom of tarsal tunnel syndrome. This is the electric shock sensation that occurs when an affected nerve is tapped.
This sensation typically travels into the affected foot but in some cases, it might travel up the inner part of the leg.
The cause of tarsal tunnel pain can be difficult to determine. Medical experts will therefore start by trying to find out if there is an underlying cause of the pain.
The treatment direction followed and the results achieved will depend on the cause of the pain. Anything or any condition that can create pressure in the tarsal tunnel can cause tarsal tunnel syndrome.
This includes things such as cysts or tumors, tendon sheath inflammation, bone spurs, nerve ganglions and swelling caused by a sprained or broken ankle. Varicose veins (may or may not be visible) have been found to cause compression that leads to the syndrome and pain.
Tarsal tunnel syndrome is more common in active individuals such as athletes. This is as a result of the force applied to the tarsal tunnel area during the different activities.
Flat feet have been observed to increase the tunnel region pressure and this may lead to compression of the nerves. In some cases, the tarsal tunnel syndrome has been associated with rheumatoid arthritis while in some, the syndrome is idiopathic.
The cause of tarsal tunnel syndrome differs with every patient. Though this is the case, the end result is the same since the condition is caused by the compression of the tibial nerve.
Since there are many causes behind the compression of the tibial nerve, there are equally many preventive measures. One of the preventive measures is immobilization where the foot is placed in a neutral position and supported by a brace in efforts to relieve the pressure from the nerve.
Proper footwear is a preventive measure since improper wear has been indicated as a cause of compression. Wearing shoes that are tight for a long time might increase the pressure to the tibial nerve and this might lead to the syndrome and cause pain.
This means that wearing properly fitting shoes can simply prevent tarsal tunnel syndrome.
The diagnosis of tarsal tunnel syndrome will depend on the finding of a physical examination. The pain history of the patient and Tine’s sign will also be used in the evaluation of the condition. X-ray may be used in ruling out fracture.
Magnetic resonance imaging might be employed in the assessment of the space occupying lesions or in identifying any other possible cause of the compression.
Other diagnostic measures include ultra sound for assessment of ganglia or synovitis and nerve conduction studies which will assist in the confirmation of the clinical diagnosis.
Treatment will include manipulation, rest, tibialis anterior and posterior strengthening, walker boot casting, corticosteroids and anesthetic injection, wrapping, hot wax, orthotics and compression hose.
Medication will mostly involve anti-inflammatories such as anaprox and other types of medications such as neurontin, lyrics, and ultracet. Some patients have reported the effectiveness of lidocaine patches.
When all the non-invasive conservative treatment methods fail, tarsal tunnel release surgery is recommended with an aim of decompressing the tunnel. There are a lot of patients that have reported improvement and recovery with the surgery but there is a noticeable percentage that has reported no improvement while others had complications.
Success of the surgery will be increased by the release of all the 4 medial ankle tunnels and the patient walks with a walker after the surgery.