49. Klippel-Feil Syndrome
Definition
Klippel-Feil syndrome is a rare congenital disorder in which any two of the seven cervical vertebrae are absent or fused, resulting in a short neck with limited range of motion.
Classification of Klippel-Feil Syndrome
Type I | Massive fusion of the cervical spine |
Type II | Fusion of one or two cervical interspaces |
Type III | Thoracic and/or lumbar spine anomalies in conjunction with Type I or II |
Incidence
The true incidence of Klippel-Feil syndrome is not known.
Etiology
The true etiology of Klippel-Feil syndrome is not fully understood. There are various suggestions as to the etiology of this malady, including congenital failure of segmentation of the cervical vertebrae, which results from failure of segmentation of cervical somites during the third through eighth weeks of gestation. Some have suggested the occurrence of some manner of global fetal insult, whereas others suggest the malady may be caused by some manner of vascular disruption.
Signs and Symptoms
For anomalies, see box below.
Anomalies Associated with Klippel-Feil Syndrome
• Brainstem anomalies
• Congenital heart disorder (most commonly ventricular septal defect)
• Congenital scoliosis
• Craniosynostosis
• Dyskinesia
• Renal disease (horseshoe kidney, renal ectopia, bilateral tubular ectasia, hydronephrosis, absent kidney)
• Sprengel’s deformity (elevation of scapula)
Klippel-Feil Syndrome. A, Short neck (fused cervical vertebrae and nonfunctioning right thumb caused by lack of tendons to this digit. Intravenous pyelogram (B) reveals crossed renal ectopia of the left kidney, whereas the ureter from the left kidney crosses the midline and inserts into the left side of the trigone. |
• Abnormal hand position
• Ataxia
• Blurred vision
• Bruxism