|
| |
| Lumbar Radiculopathy |
| Herniated disc |
90% at L4-L5 & L5-S1, which nerve root is affected
depends on whether the disc herniation is central or lateral |
| Spinal stenosis |
most common at L4-L5 & L3-L4, midsagittal diameter
<10mm |
| Root |
Signs, symptoms |
| L5 |
 | Pain: lateral leg to dorsum of foot & big toe |
| Weakness: dorsiflexion of foot and toes (tibialis
anterior & ext hallucis longus) |
| Reflex change: none |
| EMG findings
 | Peroneus longus and tensor fascia lata.
Positive in most patients. |
| Flexor digitorum longus, tibialis posterior, and tibialis anterior muscles
abnormal in over 75% of the patients. |
| Paraspinal muscles, positive in 50%. |
| Posterior tibialis or flexor digitorum longus is critical, as these are the only L5 innervated muscles below the knee not innervated by the peroneal nerve. |
|
|
| S1 |
| Pain: back of calf to lateral foot & little
toe |
| Weakness: plantar flexion and eversion of foot. |
| Reflex change: ankle jerk |
| EMG findings:
| Biceps femoris short head and long head, and medial gastrocnemius.
Exclusively innervated by the S1 root, involved in > 80% of
patients: |
| Paraspinal
muscles. 25%
of patient shows abnormalities. |
| Other S1 muscles: abductor
hallucis, gluteus maximus |
|
|
| L4 |
| Pain: back pain down to knee and to medial malleolus |
| Weakness: inversion of foot |
| Reflex change: knee jerk |
|
| L3 |
| Pain: across thigh |
| Weakness: knee extension, thigh adduction |
| Reflex change: adductor reflex |
|
| L2 |
| Pain: across thigh |
| Weakness: hip flexion, adduction |
| Reflex change: none |
|
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