Craniovertebral junction instability in Larsen syndrome: An institutional series and review of literature

Abstract

Objective: Larsen syndrome (LS) is characterized by osteo-chondrodysplasia, multiple joint dislocations, and craniofacial abnormalities. Symptomatic myelopathy is attributed to C1–C2 instability and sub-axial cervical kyphosis. In this article, we have analyzed the surgical outcome after posterior fixation in LS with craniovertebral junction instability. Methods: Ten symptomatic pediatric patients, operated between 2011 and 2019, were included, and the clinical outcome was assessed by Nurick grade, neurological improvement, and complications. The requirement of anti-spasticity drugs, the degree of bony fusion, and restriction of neck movement were also noted. At last follow-up, patient satisfaction score (PSS) and back to school status were studied. We also reviewed the literature and categorized two types of presentation of reported LS patients and discussed the pattern of disease progression among both. Results: Ten patients, age range 1.5–16 years, underwent 12 surgeries (6 C1–C2 fixation, 4 long-segment posterior cervical fixation, and 2 trans-oral decompressions as the second stage); the mean follow-up was 23 (range, 6–86 months). All the ten patients in our study had the characteristic “dish-” like face and nine patients had acral anomalies. The median Nurick grade improved from preoperative (median = 4) to follow-up (median = 3). The requirement of anti-spasticity drugs decreased in seven patients and the neck-pain improved in nine patients. The median satisfaction at follow-up was good (median PSS = 2); five patients were going back to school. Conclusion: Craniovertebral junction instability in LS is rare and surgically challenging. Early posterior fixation showed a promising outcome with a halt in the disease progression.

Keywords

• cervical kyphosis
• cranio-vertebral junction anomalies
• larsen syndrome
• long segment fusion
• sub-axial compression
• syndromic atlantoaxial dislocation