Bone Abstracts

Osteogenesis Imperfecta (OI) is a genetic condition which alters collagen biosynthesis⁽¹⁾. Prevalence is estimated at 1 in every 15, 000 births. It is a disorder with a wide spectrum of severity, with cases ranging from the extremely mild to those of perinatal mortality. Typical features include bone fragility; short stature; long bone deformity and persistent blue sclera⁽²⁾. Although currently there is no cure for OI, with the input of a multidisciplinary team those with the condition can be supported to live a full and independent live. Intramedullary fixation is a common orthopaedic intervention in children with osteogenesis imperfecta. It is associated with reduced fracture incidence and improved ambulation^(3–4). Complications such as rod migration are documented in the literature^(5–6). However a reduction in knee extension, a common clinical finding is not reflected in the current evidence base. As such a retrospective review of knee range of movement in children aged three to eighteen years diagnosis with OI who underwent intramedullary fixation at Sheffield Children’s Hospital (SCH) between 2007 and 2014 was completed. This service evaluation gained approval from the clinical governance department at SCH. Thirty children and 35 limbs were reviewed. Of the 30 children who had received orthopaedic surgery 26 had rodding of their femurs; 8 of their tibia’s and 1 of both femur and tibia jointly. Type of OI varied as did the type of intramedullary rod and post-operative care. Of the 35 limbs reviewed 15 lost knee extension following the surgery. Of these 7 resolved fully, 4 had an unknown outcome and 5 remained restricted. There is evidence to suggest that knee range of movement can be restricted post intramedullary rodding, with the suggestion that this is more likely following rodding of the tibiae. This piece of work had many limitations and as such there is a need to examination the issue further with more robust techniques.

Disclosure: The authors declared no competing interests.

Reference
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2. Forlino A, Cabral WA, Barnes AM, Marini JC. New perspectives on osteogenesis imperfecta. Nat Rev Endocrinol 2011 7 (9) 540–557.

3. Birke O, Davies N, Latimer M, Little D G, & Bellemore M. Experience with the Fassier-Duval telescopic rod: first 24 consecutive cases with a minimum of 1-year follow-up. J Pediatr Orthopaed 2011 31 (4) 458–464.

4. Esposito P, Plotkin H. Surgical treatment of osteogenesis imperfecta: current concepts. Curr Opin Pediatr 2008 Feb 1 20 (1) 52–57.

5. Lee K, Park M S, Yoo W J, Chung C Y, Choi I H, & Cho T J. Proximal migration of femoral telescopic rod in children with Osteogenesis Imperfecta. J Pediatr Orthopaed 2015 35 (2), 178–184.

6. Nicolaou N, Bowe J D, Wilkinson J M, Fernandes J A, & Bell M J. Use of the Sheffield Telescopic Intramedullary Rod System for the management of osteogenesis imperfecta. J Bone Joint Surg 2011 93 (21) 1994–2000.