Spine and Peripheral Nerve Surgery
Core concepts
Understand spinal stability concepts (three-column model), the difference between radiculopathy and myelopathy, and when urgent decompression is indicated (cauda equina syndrome, progressive myelopathy, epidural abscess/hematoma). Know the classic presentations: cervical spondylotic myelopathy (gait disturbance, hyperreflexia, Hoffman sign), lumbar stenosis (neurogenic claudication relieved by flexion), and disc herniation patterns. Understand degenerative vs traumatic vs neoplastic spine disease. For peripheral nerve, know entrapment syndromes (carpal tunnel, cubital tunnel), the role of EMG/NCS, and nerve injury classification (neurapraxia, axonotmesis, neurotmesis). Understand when fusion is added to decompression (instability, deformity, spondylolisthesis).
Traps
A classic trap is missing cauda equina syndrome (saddle anesthesia, urinary retention) and delaying surgery. Another is attributing neurogenic claudication to vascular disease. Questions may test whether a patient with a single-level radiculopathy needs surgery versus conservative care. Watch for confusing the levels of nerve root compression with the disc level (e.g., L4-L5 disc affects the L5 root).
Worked rule of thumb
Cauda equina syndrome is a surgical emergency - decompress urgently. For radiculopathy without red flags, conservative therapy first. Remember the disc-level-to-root rule in the lumbar spine: a paracentral disc herniation typically compresses the traversing root below the disc level.