F wave studies of neurogenic intermittent claudication in lumbar spinal stenosis.
OBJECTIVE
Lumbar spinal stenosis (LSS) may result in neurogenic claudication (NC), which is thought to be a result of transient ischemia during exercise. In this study we evaluated the changes in F wave studies before and immediately after walking stress in patients with NC.


METHODS
Twenty-six patients with LSS who had signs and symptoms of NC and 20 healthy volunteers were included in this study. Routine motor and sensory nerve conduction studies and tibial F wave studies were performed in both groups. Immediately after walking stress test, tibial F wave studies were repeated. Exercise treadmill protocol was used for ambulation. Time to first symptoms and total ambulation time were recorded.


RESULTS
After completion of the baseline electrophysiological examination, a walking stress test was performed using a treadmill, and 16 patients (61.5%) experienced neurogenic claudication during the trial. The mean time to first symptoms was 2.0 +/- 3.5 mins (minimum = 0, maximum = 14). In the control group 18 subjects (90%) completed the trial without any symptoms, and 2 (10%) subjects had to stop at an average of 10 mins because of generalized fatigue. Within 5 mins after the walking stress test, tibial F wave studies were repeated in both groups. There were significant increases in F latency values bilaterally in the patient group (P = 0.001 for both sides) but not in control subjects (P = 0.435 for right side and P = 0.122 for left side).


CONCLUSIONS
Our data suggest that F wave studies after walking stress test provide more information for the diagnosis of NC.
Bal
Serpil
S
Atatürk Research and Education Hospital, Department of Physical Medicine and Rehabilitation, 220 sk No: 8/4 Basin sitesi, 35360 Yzmir, Turkey.
Celiker
Reyhan
R
Palaoglu
Selçuk
S
Cila
Ayşenur
A
D016022:Case-Control Studies; D004576:Electromyography; D005080:Exercise Test; D005260:Female; D006801:Humans; D007383:Intermittent Claudication / Q000175:diagnosis / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D010147:Pain Measurement; D013130:Spinal Stenosis / Q000503:physiopathology*; D013979:Tibial Nerve / Q000503:physiopathology*