Klippel-Feil syndrome: Should additional examination be conducted?

Area of Science:

• Medical Genetics
• Radiology
• Orthopedics

Background:

• Klippel-Feil syndrome (KF) is characterized by congenital cervical vertebral fusion.
• The necessity of whole spine screening in isolated KF cases remains unclear.
• Understanding KF prevalence, associated anomalies, and risk factors is crucial for diagnosis and management.

Purpose of the Study:

• To determine the prevalence and gender distribution of Klippel-Feil syndrome.
• To classify fusion types and analyze the frequency of accompanying anomalies based on KF type.
• To investigate the association between cervical scoliosis and additional anomalies in KF patients.

Main Methods:

• Retrospective analysis of 40,450 cervical spine MRI scans from a single center.
• Evaluation for KF, fusion level, classification, cervical scoliosis, and other musculoskeletal/spinal anomalies.
• Statistical analysis to determine prevalence, gender distribution, and associations between anomaly types.

Main Results:

• Klippel-Feil syndrome was diagnosed in 0.309% of patients, with a higher prevalence in women (P < 0.001).
• Single fused segments were most common (84.8%), followed by contiguous (8.8%) and multilevel (6.4%) fusions.
• Additional anomalies were significantly more frequent in upper-level KF (P < 0.001) and in KF patients with cervical scoliosis (P < 0.001).

Conclusions:

• Klippel-Feil syndrome prevalence is 0.309%, predominantly affecting women, often at the C2-C3 level.
• Associated anomalies are particularly linked to 'contiguous fused segments' and 'upper level' KF.
• KF with scoliosis indicates a higher risk of associated anomalies, supporting the recommendation for whole spine examination.