J Korean Acad Rehabil Med.  2001 Aug;25(4):609-614.

Relation between Symptom Duration and Abnormal Spontaneous Activity in S1 Radiculopathy

• Kwon BS
• Lee SJ
• Park CH
• Chun DJ

Abstract

OBJECTIVE
It is a widely accepted belief that paraspinal muscles tend to show spontaneous activity on needle electromyography early on in a radiculopathy and distal muscles become abnormal later on. But most studies have shown the limitations of using symptom duration when interpreting electrodiagnostic findings in radiculopathy. The purpose of this study was to determine the relationship between symptom duration and abnormal spontaneous activity in S1 radiculopathy confined to abnormal H-reflex. METHOD: A retrospective study that collected the informations on symptom duration and spontaneous activity in paraspinal muscle and gastrocnemius for 112 patients with S1 radiculopathy diagnosed by unilateral H-reflex abnormality was undertaken.
RESULTS
Abnormal spontaneous activity in paraspinal muscle had shown a significant negative correlation with symptom duration, that is a tendency to decrease its expression over symptom duration. On the contrary abnormal spontaneous activity in gastrocnemius muscle was rare at first a few weeks and became to show after 7 weeks. Patients with symptom duration over 1 year had higher incidence of having no abnormal spontaneous activities both in paraspinal and gastrocnemius muscle.
CONCLUSION
These results suggested that symptom duration had a potential role in the diagnosis of S1 radiculopathy when H-reflex were abnormal unilaterally.

Keyword

Paraspinal muscle; Spontaneous activity; H-reflex; S1 radiculopathy

MeSH Terms

Diagnosis
Electromyography
H-Reflex
Humans
Incidence
Muscle, Skeletal
Muscles
Needles
Paraspinal Muscles
Radiculopathy*
Retrospective Studies