SKELETAL-DYSPLASIA- AND-ALL-ITS-TYPES.

For Orthopedics residents

1. SKELETAL DYSPLASIA BY Dr. VIVEK MADANKAR Post graduate student, Dept. of Orthopaedics, MGMH, Warangal

2. MODERATORS Dr. S. Lakshminarayana sir (Prof & Unit Chief) Dr. B. Kiran Kumar sir ( Assit . Prof.) Dr. K. Ravikanth sir ( Assit . Prof.) Dr. Bliss Agape ( Assit . Prof.)

3. Definition: “Dysplasia means abnormal development” Genetically heterogeneous group of 350 distinct disorder generalized abnormality list in the skeletal system. Affects development of chondroosseous tissues leading to abnormalitis in size, mineralization and shape of various segments of skeleton SKELETAL DYSPLASIA Shortening of the involved bones affects specific portions of the growing bone, hence the term dwarfism. Most forms of dwarfism are related to genetic defects (single or multiple genes).

4. ACHONDROPLASIA

5. Normal trunk and short limbs ( rhizomelic ) with hypotonia Normal intelligence but delayed motor milestones Frontal bossing, button nose, small nasal bridge, trident hands (inability to approximate extended middle and ring fingers) Thoracolumbar kyphosis (resolves around the age at ambulation) Lumbar stenosis (most likely to cause disability) and excessive lordosis Compression at foramen magnum (evidences of sleep apnea ) Radial head subluxation Sitting height may be normal, standing height is below the third percentile . Signs and symptoms

6. trident hands

7. Spine: narrowed interpedicular distance in the distal spine (L1–S1), T12–L1 wedging, generalized posterior vertebral scalloping Radiographic findings

8. b) Pelvis: champagne glass pelvic outlet (wider than deep), tombstone pelvis (squaring of iliac wings)

9. Treatment

10. Clinically similar to achondroplasia Autosomal dominant Defect of cartilage oligometric matrix protein (COMP) on chromosome 19 Signs and symptoms Normal facies Cervical instability and scoliosis with increased lumbar lordosis Significant lower extremity bowing Hip, knee, and elbow flexion contractures with precocious osteoarthritis Radiographic findings: Metaphyseal flaring and delayed epiphyseal ossification PSEUDOACHONDROPLASIA

11. MULTIPLE EPIPHYSEAL DYSPLASIA

12. MED is characterized by irregular delayed ossification at multiple epiphyses Radiographic findings

13. b) Short, stunted metacarpals and metatarsals, irregular proximal femora, abnormal ossification ( tibial slant sign and flattened femoral condyles , patella with double layer ), valgus knees (early osteotomy should be considered), waddling gait, and early hip arthritis are common.

14. Proximal femoral involvement can be confused with that in Perthes disease. MED is bilateral and symmetric , early acetabular changes, with no metaphyseal cysts . Treatment Physiodesis or osteotomy for limb alignment deformity physiotherapy to maintain joint motion .

15. Defect in type II collagen Must be differentiated from MED Both MED and SED involve abnormal epiphyseal development in the upper and lower extremities. Distinguishing feature of SED is the added spine involvement. Scoliosis : typically with a sharp curve over a small number of vertebrae Atlantoaxial instability with cervical myelopathy Retinal detachment and respiratory problems are common. SPONDYLOEPIPHYSEAL DYSPLASIA

16. Characterized by multiple punctate calcifications seen on radiographs during infancy Autosomal dominant form ( Conradi-Hünermann ) has a wide variation of clinical expression. Autosomal recessive rhizomelic form usually fatal during first year of life Cataracts , asymmetric limb shortening that may necessitate surgical correction, and spinal deformities are common CHONDRODYSPLASIA PUNCTATA

17. Autosomal dominant; defect in type II collagen Short-trunked , disproportionate dwarfism Joint stiffness/contractures , scoliosis, kyphosis, dumbbell-shaped femur , and hypoplastic pelvis and spine Recurrent otitis media and loss of hearing are common. Radiographic findings: osteopenia and dumbbell-shaped bones Treatment Early therapy for joint contractures is required. Reconstructive procedures may be required for early hip degenerative arthritis. KNIEST SYNDROME

18. dumbbell-shaped long bones

19. METAPHYSEAL CHONDRODYSPLASIA Heterogeneous group of disorders characterized by metaphyseal changes of tubular bones with normal epiphyses

20. Jansen (rare): Autosomal dominant most severe form Genetic defect in parathyroid hormone–related peptide Mental retardation , markedly short-limbed dwarfism with wide eyes, monkeylike stance , and hypercalcemia Striking bulbous metaphyseal expansion of long bones is a distinctive radiographic finding.

21. 2) Schmid type More common , less severe form Genetic defect is in type X collagen , autosomal dominant , short-limbed dwarfism is not diagnosed until patient is older, as a result of coxa vara and genu varum . Predominantly involves proximal femur. Gait is often Trendelenburg , and patients have increased lumbar lordosis . Condition often confused with rickets, but laboratory test results normal

22. 3) McKusick type Autosomal recessive , cartilage-hair dysplasia (hypoplasia of cartilage and small diameter of hair) is observed most commonly among the Amish population and in Finland. Atlantoaxial instability is common ( odontoid hypoplasia ). Ankle deformity develops as a result of distal fibular overgrowth. Affected patients may have abnormal immunocompetence and have an increased risk for malignancies , intestinal malabsorption , and megacolon .

23. Clinical features Autosomal dominant Affected children are often “late walkers” (because of associated muscle weakness ). Symmetric cortical thickening of long bones Tibia , femur, and humerus are most often involved ( in that order ), with only the diaphyseal portion of bone affected. Limb Length Descripancy should be watched for. PROGRESSIVE DIAPHYSEAL DYSPLASIA (CAMURATI-ENGELMANN DISEASE)

24. Symmetric cortical thickening of long bones ( diaphyseal )

25. Radiographic findings Widened fusiform diaphyses with increased bone formation and sclerosis Treatment Salicylates, NSAIDs, and steroids for refractory cases

26. Differentiated on the basis of the presence of complex sugars in the urine Accumulation of mucopolysaccharides as a result of a hydrolase enzyme deficiency Proportionate dwarfism MUCOPOLYSACCHARIDOSIS

27. Hurler syndrome (autosomal recessive ) Sanfilippo syndrome (autosomal recessive )

28. Hunter syndrome ( sex-linked recessive )

29. Morquio syndrome (autosomal recessive ) Radiological finding:

30. MUCOPOLYSACCHARIDOSES IN NUTSHELL

31. Autosomal recessive ; severe short-limbed dwarfism Deficiency in DTDST gene , which codes for sulfate transport protein Cleft palate (59% of cases) Severe joint contractures (especially hip and knee) Cauliflower ears (80% of cases), hitchhiker’s thumb Rigid clubfeet Radiographic findings cervical kyphosis (often severe, necessitating immediate treatment), thoracolumbar kyphoscoliosis (83% of cases), spina bifida occulta , and atlantoaxial instability. Treatment Quadriplegia is a major concern with deformities of the cervical spine. Early fusion required Surgical release of clubfoot deformities Osteotomies for contractures Spinal fusion often required DIASTROPHIC DYSPLASIA

32. Autosomal dominant Defect in transcription factor for osteocalcin (CBFA1) Proportionate dwarfism that affects bones formed by intramembranous ossification ( clavicles, cranium, pelvis ) Radiographic findings Hypoplasia or aplasia of the clavicle (no intervention necessary) Delayed closure of skull sutures and frontal bossing Coxa vara Delayed ossification of the pubis with small iliac wings Treatment Intertrochanteric valgus osteotomy if neck-shaft angle is less than 100 degrees CLEIDOCRANIAL DYSPLASIA (DYSOSTOSIS) (A) Anteroposterior (AP) shoulder radiographs show hypoplasia of the clavicle (B) AP pelvic radiograph shows a lack of ossification of the symphysis pubis

33. OSTEOPETROSIS Clinical features Bone pain Loss of the medullary canal can cause anemia , encroachment on the optic and oculomotor nerves, and blindness.

34. Radiographic findings Rugger jersey spine Marble bone Erlenmeyer flask deformity of proximal humerus and distal femur Treatment Healing is normal, but amount of time for healing may be prolonged. Bone marrow transplantation may be helpful for treating the “malignant” form.

35. Soft tissue swelling and bony cortical thickening (especially jaw and ulna) that follow a febrile illness in infants 0 to 9 months old This disorder may be differentiated from trauma (and child abuse) on the basis of single-bone involvement. Infection , scurvy, tumor , and progressive diaphyseal dysplasia may be included in the differential diagnosis. The condition is benign and self-limiting INFANTILE CORTICAL HYPEROSTOSIS (CAFFEY DISEASE) Clinical features

36. Thank you