From the Guidelines
Causes of Sciatica with Hyperesthesia
Herniated disc is the most likely cause of sciatica with hyperesthesia, as it can compress a nerve root, leading to pain, numbness, and tingling sensations in the leg.
- A typical history for sciatica, including back and leg pain in a typical lumbar nerve root distribution, has a fairly high sensitivity but uncertain specificity for herniated disc 1.
- More than 90% of symptomatic lumbar disc herniations occur at the L4/L5 and L5/S1 levels, which can cause hyperesthesia due to nerve root compression.
- A focused examination, including straight-leg-raise testing and a neurologic examination, can help assess the presence and severity of nerve root dysfunction.
- A positive result on the straight-leg-raise test has a relatively high sensitivity (91%) but modest specificity (26%) for diagnosing herniated disc 1.
- Other potential causes of sciatica with hyperesthesia, such as lumbar spinal stenosis, should also be considered, although the evidence on the utility of history and examination for identifying this condition is sparse 1.
From the Research
Causes of Sciatica with Hyperesthesia
- Sciatica is defined as pain or discomfort along the regions innervated by the sciatic nerve, and it can be caused by various factors, including compression or irritation of lumbar spinal roots, lumbar disc herniation, or spinal stenosis 2, 3.
- Hyperesthesia, or increased sensitivity, can occur in conjunction with sciatica, and it may be related to partial damage to dorsal root fibers at a point medial to the dorsal root ganglion 4.
- In some cases, sciatica with hyperesthesia can be caused by extraspinal factors, such as gluteal varicosities 2, sciatic herniae 5, or other local pathologies that compress the sciatic nerve.
- The symptoms and signs of sciatica, including pain projection and neurologic symptoms, can vary depending on the location and severity of the underlying cause, and may not always be reliable indicators of the level of disc herniation 6.
Possible Underlying Causes
- Compression or irritation of lumbar spinal roots, most commonly due to lumbar disc herniation or spinal stenosis 2, 3.
- Gluteal varicosities or other vascular compressive neuropathies 2.
- Sciatic herniae or other local pathologies that compress the sciatic nerve 5.
- Partial damage to dorsal root fibers at a point medial to the dorsal root ganglion, which can cause hyperesthesia 4.
Diagnostic Considerations
- A thorough examination of the course of the sciatic nerve for local pathology is necessary when the cause of sciatica is not obvious 5.
- Imaging studies, such as lumbar computerized tomography or myelography, may be recommended as a routine preoperative study to confirm the diagnosis and identify the underlying cause 3, 6.