الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 89 |  |  |
| | | from | 89 | | |
Abstract
Lumbosacral radiculopathy is a clinical disorder caused by impaired function (compression or irritation) of lumbosacral spinal nerve roots. It is manifested by LBP radiating down into LLs in a dermatomal pattern, numbness, loss or decreased reflexes and also muscle weakness along myotomal pattern may be present.
There is a wide range of etiologies of lumbosacral radiculopathy, the most common etiology is spondylodegenerative changes as LDH.
For definitive diagnosis of lumbosacral radiculopathy, there are variable diagnostic modalities which include MRI of lumbosacral spine and electrophysiological studies of LL nerves.
F wave is one of the late responses which is used to study proximal nerve involvement, it is a low amplitude response produced by antidromic activation of motor neurons.
Our objective was to evaluate the diagnostic efficacy of F wave as an electro-diagnostic test and its reliability for diagnosing lumbosacral radiculopathy in clinically suspected patients.
Thirty five patients (above 18 years old) presented with clinical manifestations of lumbosacral radiculopathy participated in this study. Another 30 healthy subjects were enrolled as a control group.
For each patient and healthy subject, the followings were done:
• Detailed history taking.
• Complete neurological examination and SLRT.
• Motor nerve conduction study of posterior tibial and deep peroneal nerves, the measured parameters were DL in ms, peak to peak CMAP amp in mV and nerve CV in m/s.
• Sensory nerve conduction study of sural and superficial peroneal nerves to exclude peripheral neuropathy.
• F wave of tibial and peroneal nerves, the measured parameters were minimal F latency in ms and F estimate.
• H reflex was performed measuring predicted H value and H latency in ms.
• MRI of the lumbosacral spine was performed.
According to neurological examination, there were affected deep tendon reflexes in 69.9% of patients, hypothesia along L 4,5 and S 1 dermatomes in 31.4% of patients, weakness of hip abductors in 17.2% of patients, hip extensors in 17.2% of patients, ankle dorsiflexors in 17% of patients, long toe extensors in 15.6% of patients, ankle plantar flexors in 17.1% of patients, and positive SLRT in 54.3% with statistical significant differences between cases and controls as regards affected deep tendon reflexes, hypothesia along L 5 and S1 dermatomes, weakness of hip abductors, hip extensors, ankle dorsiflexors, long toe extensors, ankle plantar flexors and Straight leg raising test.
According to electrophysiological assessment, There was statistically significant difference between 2 studied groups as regards the mean value of Peroneal DL, Peroneal amp, Peroneal CV(1stand 2nd segments), H reflex latency, tibial F latency and peroneal F latency.
According to MRI findings of studied patients, the most commonly affected root was S1 (61.4%) followed by L5 (60%).
There was statistical significant association between MRI findings and some clinical and electrophysiological parameters as affected knee reflex and ankle reflex, weakness of hip abductors, ankle dorsiflexors, weakness of long toe extensors, affected peroneal DL, amp and affected F wave latency and affected H reflex latency.
F wave reflects the status of proximal motor nerve conduction so in lumbosacral radiculopathy we get abnormal F wave latencies because in radiculopathy, excitability of motor neuron pool and conductive properities of different motor units are affected.
MRI and NCS are considered complementary tools for diagnosis of lumbosacral radiculopathy.