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Type V, VI, VII have been added to the original classification system (these have no Type I collagen mutation but have abnormal bone on microscopy and a similar phenotype)
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A 12-year-old girl has been diagnosed with a severe form of osteogenesis imperfecta that has resulted in thin bones and multiple fractures. She now presents for follow-up of scoliosis which was noticed by her mother 1 year ago. She has no back pain and is neurologically intact. Radiographs show a 42-degree right thoracic curve, which has increased from 31-degree from her previous radiographs taken 9 months earlier. What is the most appropriate management for her spinal deformity?
Observation alone with serial radiographic and clinical monitoring.
Posterior spinal fusion with instrumentation
Anterior spinal fusion with instrumentation
Fixation with telescoping rods
Custom-molded bracing with serial radiographic and clinical monitoring.
Select Answer to see Preferred Response
Children with severe forms of osteogenesis imperfecta and progressive scoliosis should be treated with posterior spinal fusion with instrumentation when the curve exceeds 35 degrees.
Spinal deformity is common in children with osteogenesis imperfecta, particularly in severe forms. Curves develop early and generally progress. Bracing is not indicated due to the complications associated with the brace on the soft bones of the rib cage. In the patient with severe disease with thin bones and numerous fractures, posterior correction and fusion is indicated, and should be done early when the curve is greater than 35 degrees. In the patient with mild disease and thick bones surgery is indicated when the curve is greater than 45 degrees.
Burnei et al review the diagnosis and treatment of OI. They report that medical treatment with bisphosphonates, even in patients younger than age 2 years, have become widely accepted in the symptomatic treatment of OI. They report alendronate has a proven beneficial effect, demonstrating a decrease in fracture frequency and improvement of vertebral bone density and quality of life.
Janus et al. retrospectively studied 20 children who underwent halo gravity traction and posterior spine instrumentation for scoliosis. They emphasize that correction and stabilization of the scoliotic spine in osteogenesis imperfecta is difficult, primarily due to implant pull-out due to the poor bone quality. With their technique, they found an overall improved sitting balance and an increased functional ability in 7 of 20 patients after surgery. They conclude that although partial loss of correction seems inevitable, operative stabilization is possible.
Pan et al. emphasize the surgical treatment of scoliosis in patients with osteogenesis imperfecta is difficult due to poor bone quality, which often leads to breakage of bones, dislodgement of implants, and late loss of correction. They found the usage of pedicle screw and a 3-rod fixation technique, together with cyclic intravenous bisphosphonate administration and halo-gravity traction preoperatively, contributed to improved outcomes.
Illustration A shows the sequential radiographs before and after surgical treatment of one patient from the Janus et al study. Image A,B and C is prior to surgery. Image D is immediately postoperative, and Image E and F are at 2 years. Notice in Image E and F the alignment of the spine is maintained without loss of correction despite the pull-out of the distal hook due to the fracture of the lamina.
Answer 1: Due to the progressive nature of scoliosis in children with OI, this patient should be treated with surgery.
Answer 3: Due to the pulmonary compromise associated with OI, an anterior approach is less favorable than a posterior approach.
Answer 4: A Growing rod construct is not required at age 11 and likely would be complicated in an osteopenic patient. Telescoping rods are utilizing for long bone deformity such as in the humerus or femur.
Answer 5: Bracing is minimally effective and associated with complications, and therefore, is not indicated in children with osteogenesis imperfecta and scoliosis.
Burnei G, Vlad C, Georgescu I, Gavriliu TS, Dan D
J Am Acad Orthop Surg. 2008 Jun;16(6):356-66. PMID: 18524987 (Link to Abstract)
Janus GJ, Finidori G, Engelbert RH, Pouliquen M, Pruijs JE
Eur Spine J. 2000 Dec;9(6):486-91. PMID: 11189916 (Link to Abstract)
Pan CH, Ma SC, Wu CT, Chen PQ.
J Spinal Disord Tech. 2006 Jul;19(5):368-72. PMID: 16826011 (Link to Abstract)
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Average 3.0 of 19 Ratings
A 10-year-old girl has bilateral knee radiographs as shown in Figure A. Which of the following conditions is most likely present?
Osteogenesis imperfecta (OI)
Ellis-van Creveld (EVC) syndrome/chondroectodermal dysplasia
Juvenile idiopathic arthritis (JIA)
The AP radiograph of the knee shows dense parallel bands in distal femoral and proximal tibial and fibular metaphyses. This radiographic finding is associated with long-term bisphosphonate use, and from the options provided, bisphosphonate administration is most appropriately prescribed in the setting of OI.
Poyrazoglu et al reviewed 35 patients with OI that were given pamidronate on 3 consecutive days every 3 to 4 months. They found that bone mineral density increased and fracture rate decreased in children and infants with OI during pamidronate treatment.
Onwuneme et al present a case report and discuss the radiographic findings of parallel dense metaphyseal lines in two children treated with cyclical intravenous pamidronate. It has been found that the number of lines correspond to the number of pamidronate treatments received and the separation of the lines was determined by the age of the child and the rate of growth of the bone imaged.
Namazi presents a Level 5 editorial on an article authored by Bajpai et al. Bajpai et al conducted a study on 20 OI patients and found that pamidronate treatment led to an increase in bone mineral density (BMD) Z score and a decrease in fracture rate.
Illustration A and B demonstrates an OI patient with history of multiple fractures and horizontal parallel metaphyseal lines from chronic pamidronate therapy.
J Pediatr Orthop. 2009 Sep;29(6):650-1. PMID: 19700999 (Link to Abstract)
Poyrazoglu S, Gunoz H, Darendeliler F, Bas F, Tutunculer F, Eryilmaz SK, Bundak R, Saka N
J Pediatr Orthop. 2008 Jun;28(4):483-7. PMID: 18520289 (Link to Abstract)
Onwuneme C, Abdalla K, Cassidy N, Hensey O, Ryan S.
Arch Dis Child. 2007 Dec;92(12):1087. PMID: 18032639 (Link to Abstract)
Average 4.0 of 21 Ratings
Which of the following pediatric congenital disorders is caused by a glycine substitution in the procollagen molecule?
Osteogenesis imperfecta (OI) is caused by a defect in Type I collagen (COL1A1 and COL1A2) that causes abnormal cross-linking via a glycine substitution in the procollagen molecule. This defect leads to decreased collagen secretion, bone fragility, “wormian” bones, short stature, scoliosis, tooth defects, hearing defects, and ligamentous laxity.
The article by Cole explains that OI includes a wide spectrum of disease and has various inheritance patterns (autosomal dominant or autosomal recessive). Fibrous dysplasia is caused by a germ line defect in the Gsa protein. Scurvy is caused by a vitamin C deficiency that causes a decrease in chondroitin sulfate synthesis and subsequent defect in intracellular hydroxylation of collagen peptides. Diastrophic dysplasia is caused by a mutation of a gene coding for a sulfate transport protein. Ochronosis (alkaptonuria) is caused by a defect in the homogentisic acid oxidase system.
Clin Orthop Relat Res. 1997 Oct;(343):235-48. PMID: 9345229 (Link to Abstract)
Average 3.0 of 22 Ratings
Type I collagen defects are responsible for the clinical manifestations of osteogenesis imperfecta. Mutation of what gene or genes are most responsible for this?
Pathological manifestions of osteogenesis imperfecta (OI) occur because of abnormal collagen type I. Clinical manifestions include multiple fractures, blue sclera, and scoliosis. The genes responsible for collagen synthesis are COL1A1/COL1A2 and many mutations have been characterized which result in OI. Quantitative collagen defects result in the milder OI form whereas qualitative collagen defects result in more severe clinical manifestations.
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An adolescent male with a known genetic mutation of COL1A1 presents to the emergency department with symptoms of unsteady gait and difficulty with buttoning his shirt. On physical exam, when the patient holds his fingers extended and adducted, the small finger spontaneously abducts. Snapping of the patient's distal phalanx of the middle finger leads to spontaneous flexion of the other fingers. What is the most likely cause of the patient's symptoms?
C6 cervical disc foraminal herniation
Ossification of the posterior longitudinal ligament (OPLL)
The clinical presentation is consistent for symptoms of myelopathy in a patient with Osteogenesis imperfecta (OI). Basilar invagination is the most likely cause.
Osteogenesis imperfecta (OI) is a genetic disease resulting from mutations in type I collagen genes causing bone fragility and deformities (including wormian bone appearance). Patients with osteogenesis imperfecta are known to develop basilar invagination, defined as a protrusion of the odontoid process into the foramen magnum. Basilar invagination is commonly seen with Klippel-Feil syndrome, occipitocervical synostosis, achondroplasia, osteogenesis imperfecta, Morquio syndrome, and spondyloepiphyseal dysplasia.
Kovero et al evaluated skull base anatomy in 54 patient with OI (type I, III, and IV) and 108 controls. They found 22.2% of the OI group had basilar invagination while none of the controls did. Screening radiographs are recommended in this group along with MRI in those whose films suggest the possibility of basilar invagination. Surgical decompression and fusion is recommended in those with neurologic symptoms. In patients with severe OI, an open door maxillotomy may be required (Le Fort I osteotomy of the maxilla combined with a midline split of the soft palate and maxilla).
Illutrations A and B are CT and MRI images, respectively, that demonstrate basilar invagination with associated central canal stenosis.
Answer 2: Cervical disc foraminal herniation is not associated with Osteogenesis imperfecta (OI) and would not cause myelopathy.
Answer 3: Atlantoaxial instability is often associated with Down's syndrome but is not commonly associated with Osteogenesis imperfecta (OI).
Answer 4: OPLL is not associated with Osteogenesis imperfecta (OI).
Answer 5: Epidural abscess is not commonly associated with Osteogenesis imperfecta (OI).
Kovero O, Pynnönen S, Kuurila-Svahn K, Kaitila I, Waltimo-Sirén J
J. Neurosurg.. 2006 Sep;105(3):361-70. PMID: 16961127 (Link to Abstract)
Average 3.0 of 26 Ratings
A mutation in the COL1A1 and COL1A2 genes is associated with all of the following manifestations EXCEPT:
Olecranon apophyseal avulsion fractures
Discoloration of sclerae
A mutation in the COL1A1 and COL1A2 genes results in a weakened organic bone matrix (qualitative defect in Type I collagen) and is the underlying cause of Osteogenesis Imperfecta (OI). Quantitative defects in Type I collagen result in less severe forms of OI.
Kocher et al reviews the various orthopaedic conditions associated with osteogenesis imperfecta. These conditions include bone bowing, multiple fractures, olecranon apophyseal fractures, dentinogenesis imperfecta resulting in brownish opalescent teeth, hearing loss, blue sclerae , joint hyperlaxity, basilar invagination, severe scoliosis, and wormian skull bones.
Cole et al discusses how the discovery of the collagen mutation in OI (COL1A1 and COL1A2 genes) can serve as a template to discover the genetic etiologies for other connective tissue disorders.
Illustration A shows basilar invagination with the tip of the odontoid and anterior arch of atlas are well above Chamberlain line (white line) and the clivus canal angle is <150° (yellow line).
Illustration B shows blue sclerae associated with OI.
Illustration C shows an olecranon apophyseal avulsion fracture and its postoperative fixation is shown in Illustration D.
Illustration E demonstrates the scoliosis associated with OI.
Kocher MS, Shapiro F.
J Am Acad Orthop Surg. 1998 Jul-Aug;6(4):225-36. PMID: 9682085 (Link to Abstract)
J Pediatr Orthop. 1993 May-Jun;13(3):392-403. PMID: 8496379 (Link to Abstract)
A 12-year-old girl presents with a history of numerous long bone fractures in the past. Examination reveals normal-appearing sclera, and the dentin abnormality shown in Figure A. A radiograph of her lower extremities is shown in Figure B. The patient’s disorder is the result of which of the following?
Vitamin D deficiency
Abnormal osteoclast function
Qualitative defect of type I collagen synthesis
Mutated fibroblast growth factor receptor
Defective N-Ac-Gal-6 sulfate sulfatase enzyme
The question stem is describing a patient with osteogenesis imperfecta Type IV, which is caused by a qualitative defect in the synthesis of Type I collagen. Inherited or spontaneous genetic mutations of genes COL1A1 and COL1A2 are known to be the basic anomaly that alters the collagen synthesis and structure. The quantitative disorders of type I collagen are associated with milder forms of OI (Type I), whereas the qualitative disorders are associated with more severe phenotypes (Types II, III and IV). Moderate clinical severity with white sclera and dentinogenesis imperfecta, shown in Figure A, are classically associated with Type IV OI. Figure B demonstrated lower extremity bowing and malunion, characteristic of OI.
In their review article, Baitner et al describe the major osteochondrodysplasias, define their causes and clinical manifestations, and discuss the underlying molecular defects as well as the anatomical aspects of these disorders.
1-Vitamin D deficiency is associated with Rickets, of which there are many types. It presents with a variety of symptoms including genu varum, increased fracture risk, and bone pain.
2-Abnormal osteoclast function is associated with osteopetrosis, and excessive bone accumulation and fragility.
4-Mutated FGFR is associated with achondroplasia.
5-Defective N-Ac-Gal-6 sulfatase enzyme is associated with Morquio Syndrome.
Baitner AC, Maurer SG, Gruen MB, Di Cesare PE.
J Pediatr Orthop. 2000 Sep-Oct;20(5):594-605. PMID: 11008738 (Link to Abstract)
A child has a genetic disorder of the COL1A1 gene resulting in a decreased production of functional type I collagen. Which of the following radiographs is MOST consistent with his condition?
Figure D depicts a telescoping rod in the right femur and bowing of the left femur with coxa vara; a common finding in osteogenesis imperfecta (OI). OI is a genetic defect which results in abnormal type I collagen with subsequent fragility fractures.
Figure A shows dysplastic clavicles, characteristic of cleidocranial dysplasia. Figure B is a hand radiograph showing dense bone and obliterated medullary canals, suggesting osteopetrosis. Figure C shows epiphyseal abnormalities found in multiple epiphyseal dysplasia (MED) or spondyloepiphyseal dysplasia (SED). Figure E depicts squared iliac wings and horizontal acetabuli, characteristic of achondroplasia.
Cole et al provide an overview of OI and non-skeletal manifestations including blue sclera and long bone bowing (Illustrations A and B). There were initially four, but now seven types of OI based on severity and inheritance (see Review Topic).
Average 4.0 of 25 Ratings
HPI - 1 week history of left elbow pain. X-rays taken show a chronic non union of olecranon. Patient and parents can NOT remember ever having any problems with the elbow.
How would you treat this acute on chronic fracture?