The evaluation of the inverted supinator reflex in asymptomatic patients.
METHODS
A prospective study was undertaken over a 6-month period to determine the incidence of the inverted supinator reflex in asymptomatic, neurologically normal individuals.


OBJECTIVE
The objective of our study is to assess asymptomatic patients for the presence of the inverted radial reflex and to determine its clinical relevance.


BACKGROUND
The inverted radial reflex sign is commonly used in clinical practice to assess cervical myelopathy. It is unknown whether the sign correlates with the presence or severity of myelopathy, and no consensus exists regarding the significance of a positive sign in asymptomatic individuals.


METHODS
Patients attending the Trauma Clinic at our institution were invited to participate. Each patient was examined neurologically and specifically for the presence or absence of the Babinski test, Hoffman's sign, the finger escape sign, static and dynamic Romberg's test, and the inverted supinator reflex. Patients were excluded if they had any history of neck pain, any history of neurosurgical procedure or spinal surgery, any known neurologic disorder or deficit, or if there was any outstanding medicolegal case.


RESULTS
We examined 277 patients in 6-month period. The male to female ratio was 1.1:1. The mean age was 27 years (range, 16-78). The incidence of the inverted supinator reflex was 27.6% (75/271). Of the 75 positive patients, the inverted supinator reflex was present bilaterally in 39% (29/75). Nine of 75 patients (10%) had an associated positive Hoffman's sign but had no other signs suggestive of myelopathy. The proportion of patients with a positive inverted supinator reflex reduced with increasing age (Pearson correlation coefficient > 0.80).


CONCLUSIONS
This study demonstrates that an isolated, inverted supinator reflex may be a variation of normal clinical examination. We believe that an isolated inverted supinator reflex, in the absence of other clinical findings, is not a reliable sign of cervical myelopathy; however, it must be interpreted with caution in the older patient.
Kiely
Paul
P
National Spinal Injuries Unit, Department of Trauma and Orthopaedic Surgery, Mater Misericordiae Univeristy Hospital, Eccles Street, Dublin 7, Ireland.
Baker
Joseph F
JF
O'hEireamhoin
Sven
S
Butler
Joseph S
JS
Ahmed
Motaz
M
Lui
Darren F
DF
Devitt
Brian
B
Walsh
Alan
A
Poynton
Ashley R
AR
Synnott
Keith A
KA
D000293:Adolescent; D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D012021:Reflex, Abnormal; D013118:Spinal Cord Diseases / Q000175:diagnosis* / Q000503:physiopathology