Klippel-Feil syndrome: rare clinical associations and significance

Abstract

Klippel–Feil syndrome (KFS) is a rare congenital disorder characterized by fusion of cervical vertebrae and accompanied by a wide spectrum of systemic anomalies. This narrative review summarizes current knowledge on the genetic basis, clinical spectrum, and rare associations of KFS with implications for multidisciplinary care. Recent genetic studies have identified variants in several developmental pathways, suggesting an emerging concept of oligogenic inheritance and variable expressivity. Clini-cally, beside the classic triad of short neck, low posterior hairline, and restricted cervical motion, pati-ents may present with scoliosis, Sprengel deformity, craniovertebral junction abnormalities, split cord malformations, posterior fossa lesions, and genitourinary and cardiovascular anomalies. Otologic invol-vement, including conductive or sensorineural hearing loss and cochlear implant challenges, further complicates management. Awareness of potential difficult airway and spinal cord vulnerability is cru-cial for anesthesiologists and surgeons. Early recognition, systematic screening for associated anomalies, and coordinated follow-up are essential to prevent complications and optimize long-term outcomes. We narratively reviewed recent clinical, radiologic, and genetic literature to contextualize reported prevalen-ces and rare associations.

Keywords

• Klippel-Feil syndrome
• congenital abnormalities
• spinal diseases

Klippel-Feil sendromu: nadir klinik ilişkiler ve önemi

Abstract

Klippel–Feil sendromu (KFS), servikal vertebraların konjenital füzyonu ile karakterize, çok sayıda sistemik anomali ile birlikte görülebilen nadir bir gelişimsel bozukluktur. Bu derlemede, KFS’nin gene-tik altyapısı, klinik özellikleri ve nadir eşlik eden durumları güncel literatür ışığında ele alınmakta; multidisipliner yaklaşımın önemi vurgulanmaktadır. Son yapılan genetik çalışmalar, birden fazla geli-şimsel yolakta saptanan varyantları ortaya koymuş olup, tek genli bir mekanizmadan ziyade değişken ekspresyonla seyreden, ortaya çıkmakta olan oligenik bir katkıya işaret etmektedir. Klinik olarak, kısa boyun, düşük posterior saç çizgisi ve servikal hareket kısıtlılığından oluşan klasik triada ek olarak; skolyoz, Sprengel deformitesi, kraniovertebral bileşke anomalileri, split kord malformasyonları, poste-rior fossa patolojileri ile genitoüriner ve kardiyovasküler anomaliler eşlik edebilir. Ayrıca iletim tipi veya sensörinöral işitme kaybı gibi otolojik tutulumlar ve bu hastalarda koklear implant uygulamala-rında karşılaşılan teknik güçlükler, klinik yönetimi daha karmaşık hâle getirebilir. Anestezi ve cerrahi girişimler sırasında zor havayolu yönetimi ve spinal kord yaralanması riski açısından dikkatli olunması büyük önem taşımaktadır. Erken tanı, eşlik eden anomalilere yönelik sistematik tarama ve disiplinler arası koordineli izlem, komplikasyonların önlenmesi ve uzun dönem klinik sonuçların iyileştirilmesi açısından kritik rol oynamaktadır. Bildirilen prevalansları ve nadir birliktelikleri bağlamsallaştırmak amacıyla güncel klinik, radyolojik ve genetik literatür narratif olarak gözden geçirilmiştir.

Keywords

• Klippel-Feil sendromu
• konjenital anomaliler
• spinal hastalıklar

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