Is Neuropathy Associated with Klippel-Feil Syndrome?
Yes, neuropathy is definitively associated with Klippel-Feil syndrome (KFS), manifesting primarily as nerve pain, nerve root compression, and myelopathy due to the anatomical abnormalities of cervical vertebral fusion.
Evidence of Neurological Involvement
The association between KFS and neuropathy is well-documented in recent literature. In a comprehensive analysis of 75 KFS patients, 93.3% experienced pain associated with their condition, with nerve pain being a prominent feature 1. The nerve pain was characterized as tingling/pins and needles (49% of patients) and was primarily located in the shoulders/upper back (76%), neck (72%), and back of head (50.7%) 1.
Specific Neuropathic Manifestations
Patients with KFS experience several distinct neuropathic presentations:
- Nerve root compression: Progressive bilateral paraesthesias and motor weakness in specific cervical distributions (C6, C7, C8) have been documented 2
- Myelopathy: Spinal cord compression occurs when the cord is displaced or stretched by the anatomical abnormalities, particularly in cases with anterior cervical meningomyelocele 2
- Limb numbness and weakness: These are recognized neurological manifestations of the syndrome 3, 4
Severity Correlates with Fusion Pattern
Type III fusions (multilevel, contiguous cervical fusions) are significantly associated with greater nerve pain compared to other fusion types (p = 0.02) 1. Patients with cervical fusions in the middle region (C2-6) tend to report greater nerve pain (p = 0.06) 1. This correlation is critical for risk stratification.
Mechanism of Neuropathy
The neuropathy in KFS results from:
- Mechanical compression: Fused vertebrae create abnormal biomechanics, leading to degenerative changes and neural compression in adjacent intervertebral discs 5
- Spinal cord tethering: In cases with associated meningomyelocele, the spinal cord can be displaced and severely stretched, affecting nerve roots 2
- Instability: Hypermobility at segments adjacent to fused vertebrae causes chronic nerve irritation
Clinical Implications
Surgical intervention in KFS patients is frequently indicated for neurological symptoms 5. In one series, 26% of patients underwent spine surgery, primarily for stenosis and myelopathy, with 75% of procedures performed at or adjacent to the level of congenital fusion 5. Surgery involving osseous decompression, untethering, and adhesiolysis under electrophysiological monitoring can provide significant radiological and clinical improvement 2.
Important Clinical Pitfalls
- Do not dismiss persistent neck pain and upper extremity symptoms as simple musculoskeletal complaints in KFS patients—these may represent progressive nerve root compression requiring intervention
- Median age when pain worsens is 28 years 1, so maintain long-term surveillance even in initially asymptomatic patients
- Patients requiring surgery typically have more comorbidities and neurological symptoms (balance and gait disturbances) but not necessarily more pain than non-surgical patients 1
Diagnostic Approach
When evaluating suspected neuropathy in KFS:
- MRI is essential to identify spinal cord displacement, nerve root compression, and associated anomalies like meningomyelocele 2, 3
- Electrophysiological monitoring (evoked somatosensory potentials) should be used intraoperatively when surgical intervention is pursued 2
- Look for associated conditions: Split cord malformations commonly occur with KFS and can contribute to neurological symptoms 6
The evidence clearly establishes that neuropathy is not merely an incidental finding but a core feature of KFS requiring systematic evaluation and management.