1. Ludwig Boltzmann Institute of Osteology, at the Hanusch Hospital of WGKK and, AUVA Trauma Centre Meidling, First Medical Department, Hanusch Hospital, Vienna, Austria.
2. Orthopaedic Hospital of Speising, Paediatric Department, Vienna, Austria.
3. Institute of Radiology and Research -Ibn Zohr Centre of Radiology, Tunis, Tunisia.
4. Pediatric Orthopedic Institute n.a. H. Turner, Department of Foot and Ankle Surgery, Neuro-Orthopaedics and Systemic Disorders, Saint-Petersburg, Russia.
5. Department of Radiology-Hanusch Hospital; Vienna, Austria.
Objective: To further investigate the underlying pathology of axial and appendicular skeletal abnormalities such as painful spine stiffness, gait abnormalities, early onset osteoarthritis and patellar instability in patients with Stickler syndrome type I. Radiographic and tomographic analyses were organized.
Methods: From a series of Stickler syndrome patients followed from early life to late childhood. Ten patients (6 boys and four girls of different ethnic origins were consistent with the diagnosis of Stickler syndrome type I ). Phenotypic characterization was the baseline tool applied for all patients and genotypic correlation was performed on four families
Results: A constellation of axial abnormalities namely; anterolateral ossification of the anterior longitudinal spinal ligament with subsequent fusion of two cervical vertebrae, early onset Forestier disease (progressive spinal hyperostosis with subsequent vertebral fusion on top of bridging osteophytes and “Bamboo-like spine” resembling ankylosing spondylitis) and severe premature spine degeneration were evident. Appendicular abnormalities in connection with generalized epiphyseal dysplasia were the underlying aetiology in patients with Intoeing gait and femoral anteversion, early onset severe osteoarthritis of the weight bearing joint. Remarkable trochleo-patellar dysplasia secondary to severe osteoarthritis causing effectively the development of patellar instability was additional pathology. Mutation of COL2A1 has been confirmed as the causative gene for Stickler syndrome type I
Conclusion: We concluded that conventional radiographs and the molecular determination of a COL2A1 in patients with (Stickler syndrome type I) are insufficient tools to explain the reasons behind the tremendous magnitude of axial and appendicular skeletal abnormalities. We were able to modify the criteria of the clinical phenotype as designated by Rose et al in accordance with the novel axial and appendicular criteria as emerged from within our current study.
Keywords: Stickler syndrome type I, Mutation of COL2A1 gene, Premature spine degeneration, Forestier disease, Intoeing gait, Osteoarthritis, Patellar instability, CT scan.