Abstract
Purpose
Tarsal Tunnel Syndrome (TTS) was first reported by Keck and Lam separately in 1962. It has been regarded as the lower limb equivalent to Carpal Tunnel Syndrome (CTS). The gold standard of diagnosis proposed over the years is nerve conduction study (NCS). In reality, TTS is much harder to diagnose and treat compared to CTS. Signs and symptoms can be mimicked by other foot and ankle conditions. Our unit had not seen a single positive nerve conduction result of TTS in clinically suspicious cases. We have therefore audited our 10 year experience.
Methods and Results
This is a retrospective audit. Patient list retrieved from neurophysiology. 42 patients were identified. All were referred with a clinical suspicion of TTS. There was no single positive nerve conduction result showing tarsal tunnel compression. Of these, 27 case notes were retrieved (64%). The demographics are: A) age (23 to 78), B) 12 males, 15 females, and C) 12 involving left side, 4 right side and 11 bilateral. These studies were conducted according to national guidelines. There were 8 abnormal studies: 4 showing spinal radiculopathy, 3 showing higher peripheral neuropathy and 1 showing tibial nerve irritation following previous decompression. 4 cases were operated on. These are: 2 for removal of lumps, 1 for partial plantar fascia release, and 1 for redo-decompression. As for the rest: 16 had no change in the symptoms and were discharged, 6 were referred to other disciplines, 2 resolved spontaneously, 2 lost to follow up and 1 resolved after a total knee replacement.
Conclusion
Our result does not reflect the findings reported in the literature in the past. Our neurophysiologist also agreed it is very rare to see one positive test. We feel that our understanding of TTS is not complete. The routine NCS done at resting position may not be able to replicate the clinical situations which bring on the symptoms in the first place. Changing lifestyle and improved footwear designs may also have contributed to a change in disease presentation. Further studies are required to clarify the situation.