CHAPTER 19 • ELECTRODIAGNOSTIC TESTING 117- The medial plantar nerve is easily tested as a motor
nerve conduction study, stimulating at the tibial nerve
proximal to the medial malleolus and recording over
the abductor hallucis. - The lateral plantar motor nerve study is performed by
stimulating the tibial nerve proximal to the medial malle-
olus and recording over the flexor digit minimi brevis. - The inferior calcaneal motor nerve study is performed
to the abductor digiti minimi pedis. - The medial calcaneal nerve can be studied as a sensory
nerve antidromic study, where the recording electrode
is placed over the skin of the medial calcaneus. - The sensory components of the medial and lateral
plantar nerves may be practically tested with an
antidromic mixed nerve study. - The medial and lateral plantar nerves are stimulated
individually at the plantar aspect of the foot and the
SNAP is recorded under the medial malleolus.
PERONEAL NERVE
- The peroneal nerve’s motor and sensory components
can be consistently studied with nerve conduction
studies. - The motor nerve study is performed by stimulating the
peroneal nerve at multiple sites, including the anterior
ankle, the fibular head, and the popliteal fossa. - Recording is usually over the extensor digitorum
brevis; however, the anterior tibialis can be used as an
alternative muscle. - The sensory nerve study is performed by stimulating
the superficial peroneal branch as it exits the lateral
compartment and recording over the ankle.
EMG REPORT
- The electrophysiologic report should include a number
of important pieces of data for the referring physician. - The report should correlate with physical finding and
any discrepancies identified. Inconsistencies may
have as much importance in the clinical treatment of
the patient as consistent results. - Also, the degree of definitiveness of findings needs to
be conveyed to the referring physician. A diagnosis of
S1 radiculopathy by H reflex changes alone will carry
different weight than abundant spontaneous activity in
the S1 myotomal distribution. - One abnormal finding does not make the diagnosis if
all other evidence is pointing to a different diagnosis
(Rogers, 1996).
•Sufficient evidence to rule out alternative possibilities
and to identify superimposed conditions
•Degree of injury and chronicity, if possible- Prognosis is critical if obtainable
- Comparison with previous EDX data whenever possible
SUMMARY•Effectiveness and reliability of EDX in detecting
pathology in athletes is high, but it must always be
understood in light of its capabilities and limitations.- EDX studies are examiner-dependent and when possi-
ble, should be performed by a physician who is a spe-
cialist in EDX medicine. - EDX studies evaluate the degree and location of nerve
injury but do not measure pain. - When performed at the appropriate time, athletes with
neurologic symptoms may be aided by EDX studies.
REFERENCES
Bachner EJ, Friedman MJ: Injuries to the leg, in Nicholas JA,
Hershman EB (eds.), The Lower Extremity and Spine in Sports
Medicine, St. Louis, MO, Mosby, 1995.
Basmajian JV, DeLuca CJ: Muscles Alive: Their Functions Reve-
aled by Electromyography,5th ed. Baltimore, MD, Williams &
Wilkins, 1988.
Dimitru D: Electrodiagnostic Medicine. Philadelphia, PA,
Hanley & Belfus, 1995.
Dyck PJ, Classen SM, Stevens JC, et al: Assessment of nerve
damage in the feet of long-distance runners. Mayo Clin Proc
62:568, 1987.
Feinberg JH: The role of electrodiagnostics in the study of muscle
kinesiology, muscle fatigue and peripheral nerve injuries in
sports medicine. J Back Musculoskelet Med 12;73, 1999.
Fisher MA: AAEM Minimonograph: Part 13: H reflexes and F 2
waves: Physiology and clinical indications. Muscle Nerve
15:1223, 1992.
Fisher MA: The contemporary role of F-wave studies. F-wave
studies: Clinical utility (see comments). Muscle Nerve 21:
1098, discussion 1105, 1998.
Fishman LM, Zybert PA: Electrophysiologic evidence of piri-
formis syndrome. Arch Phys Med Rehabil 73:359, 1992.
Jackson DL, Haglund B: Tarsal tunnel syndrome in athletes. Case
reports and literature review. Am J Sports Med 19:61, 1991.
Jensen MC, Brant-Zawadzki MN, Obuchowski N, et al: Magnetic
resonance imaging of the lumbar spine in people without back
pain. N Engl J Med 331:69, 1994.
Kraft GH: Fibrillation potential amplitude and muscle atrophy
following peripheral nerve injury. Muscle Nerve 13:814, 1990.
Leach RE, Purnell MB, Saito A: Peroneal nerve entrapment in
runners. Am J Sports Med 17:287, 1989.
Mann RA: Biomechanics of running, in Nicholas JA, Hershman
EB, (eds.), The Lower Extremity and Spine in Sports Medicine,
St. Louis, MO, Mosby, 1995, p 335.
Park TA, Del Toro DR: Electrodiagnostic evaluation of the foot.
Phys Med Rehabil Clin North Am 9(87):vii, 1998.