LE JOURNAL CANADIEN DES SCIENCES NEUROLOGIQUES
which ultimately spread to the remaining digits. He denied any
symptoms of radiating pain or paresthesias.
REFERENCES
1. Radin EL. Tarsal tunnel syndrome. Clin Orthop 1983; 181:167-170.
2. Oh SJ, Meyer RD. Entrapment neuropathies of the tibial (posterior
tibial) nerve. Neurol Clin 1999; 17(3):593-615.
Ill-fitting footwear or tight casts are the most common causes
of external compression in TTS.12,13 Other causes include focal
foot trauma, tumours, tenosynovitis, bony deformities, ganglion,
anomalous or hypertrophied foot muscles, fibrous bands,
varicosities, biomechanical dysfunction, and a variety of
systemic diseases, which promote nerve entrapment.4 Tarsal
tunnel syndrome has also been reported in athletes, particularly
in runners and mountain climbers.5-7,11,14-18 As well, ski boots
have been implicated in the development of TTS.11,19,20 Our case
is an example of suspected TTS caused by a hockey skate with
inflatable bladders designed to promote a better fit. His remote
history of left ankle surgery is unlikely to be directly
contributory to his symptoms as he made complete clinical
recovery and X-rays of the left foot and ankle at the time of our
assessment revealed only mild osteoarthritic changes.
3. Cimino WR. Tarsal tunnel syndrome: review of the literature. Foot
Ankle Int 1990; 11:47-52.
4. Dumitru D. Focal peripheral neuropathies. In: Electrodiagnostic
Medicine. Philadelphia: Hanley & Belfus, Inc., 1995:905-908.
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treatment and prevention. Sports Med 1993; 16(2):130-147.
6. Hainline B. Nerve injuries. Med Clin North Am 1994; 78(2):327-343.
7. Schon LC. Nerve entrapment, neuropathy, and nerve dysfunction in
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8. Kimura J. Electrodiagnosis in Diseases of Nerve and Muscle:
Principles and Practice. 3rd ed. New York: Oxford University
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9. Miller RG, Peterson GW, Daube JR, Albers JW. Prognostic value of
electrodiagnosis in Guillain-Barre syndrome. Muscle Nerve
1988; 11: 769-774.
10. DeLisa JA, Saeed MA. The tarsal tunnel syndrome. Muscle Nerve
1983; 6:664-670.
In electrophysiological studies of TTS, sensory or mixed
nerve conduction studies are more likely to be abnormal than
motor conduction studies.2,11,21,22 Initially, our case showed a
significant reduction in the left medial and lateral plantar mixed
nerve amplitudes with mildly slowed conduction velocities. The
left abductor hallucis negative peak amplitude was only
modestly reduced. Repeat studies 1.5 months later, after the
patient stopped wearing his hockey skates, demonstrated
significant improvement in the medial plantar sensory response
and modest improvement in the abductor hallucis response.
In the rare instances when TTS is present, it is more likely to
show electrophysiological changes of axonal loss rather than
focal demyelination.23 The reduced motor and sensory negative
peak amplitudes without electrophysiological evidence of motor
conduction block and the observation of fibrillation potentials
and positive sharp waves suggest that in our case the primary
pathology was axonal. It is possible that there may have been
conduction block in the mixed plantar nerve studies across the
tarsal tunnel, however, the electrophysiological concerns of
phase cancellation outweighed any attempts to accurately
quantify this possibility.8 In our case, the mechanisms
responsible for injury were likely mechanical compression and
ischemia, although it is difficult to determine the relative
contribution of each.24-26
11. Jackson DL, Haglund B. Tarsal tunnel syndrome in athletes: case
reports and literature review. Am J Sports Med 1991; 19(1):61-65.
12. Ward PJ, Porter ML. Tarsal tunnel syndrome: a study of the clinical
and neurophysiological results of decompression. J R Coll Surg
Edinb 1998; 43(1):35-36.
13. Bailie DS, Kelikian AS. Tarsal tunnel syndrome: diagnosis, surgical
technique, and functional outcome. Foot Ankle Int 1998;
19(2):65-72.
14. Henricson AS, Westlin NE. Chronic calcaneal pain in athletes:
entrapment of the calcaneal nerve? Am J Sports Med 1984;
12:152-154.
15. Hirasawa Y, Sakakida K. Sports and peripheral nerve injury. Am J
Sports Med 1983; 11(6):420-426.
16. Murphy PC, Baxter DE. Nerve entrapment of the foot and ankle in
runners. Clin Sports Med 1985; 4(4):753-763.
17. Rask MR. Medial plantar neurapraxia (jogger’s foot). Clin Orthop
Rel Res 1978; 134:193-195.
18. Schon LC, Baxter DE. Neuropathies of the foot and ankle in
athletes. Clin Sports Med 1990; 9(2):489-509.
19. Antonini G, Gragnani F, Vichi R. Tarsal tunnel syndrome in skiers.
Case report. Ital J Neurol Sci 1993; 14(5):391-392.
20. Yamamoto S, Tominaga Y, Yura S, Tada H. Tarsal tunnel syndrome
with double causes (ganglion, tarsal coalition) evoked by ski boots.
Case report. J Sports Med Phys Fitness 1995; 35(2):143-145.
21. Galardi G, Amadio S, Maderna L, et al. Electrophysiologic studies
in tarsal tunnel syndrome. Diagnostic reliability of motor distal
latency, mixed nerve and sensory nerve conduction studies. Am J
Phys Med Rehabil 1994; 73:193-198.
22. Oh SJ, Sarala PK, Kuba T, et al. Tarsal tunnel syndrome:
electrophysiological diagnosis. Ann Neurol 1979; 5:327-330.
23. Wilbourn AJ. Two uncommon nerve entrapment disorders: thoracic
outlet syndrome and tarsal tunnel syndrome. AAN 52nd Annual
Meeting, Apr 29-May 6, 2000, San Diego, California; Course #
2DS.010.
CONCLUSION
We report a rare case of suspected TTS caused by an
inflatable ice hockey skate. The patient improved clinically and
electrophysiologically when he stopped wearing the boot.
Importantly, the patient continued to remain active without
provoking symptoms of TTS while wearing other sport footwear.
24. Yates SK, Hurst LN, Brown WF. The pathogenesis of pneumatic
tourniquet paralysis in man. J Neurol Neurosurg Psychiat 1981;
44:759-767.
25. Fowler TJ, Danta G, Gilliatt RW. Recovery of nerve conduction
after a pneumatic tourniquet: observations on the hind-limb of the
baboon. J Neurol Neurosurg Psychiat 1972; 35:638-647.
26. Fullerton PM. The effect of ischaemia on nerve conduction in the
carpal tunnel syndrome. J Neurol Neurosurg Psychiat 1963;
26:385-397.
ACKNOWLEDGEMENT
The authors thank Mr. George Moogk for the artwork and Ms. Cathy
Stuart for the photography.
Volume 29, No. 4 – November 2002
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