Introduction Epidemiology most common skeletal dysplasia Genetics autosomal dominant (AD) a sporadic mutation initially in >80%, then AD risk increases with advanced paternal age caused by G380 mutation of FGFR3 (fibroblast growth factor receptor 3, on chromosome 4P) gain of function mutation that increases inhibition of chondrocyte proliferation in the proliferative zone of the physis results in defect in endochondral bone formation a quantitative cartilage defect Associated conditions medical conditions weight control problems hearing loss tonsillar hypertrophy frequent otitis media spinal manifestations lumbar stenosis patients at risk due to short pedicles, thick facets and ligamentum flavum most likely to cause disability thoracolumbar kyphosis foramen magnum stenosis may cause periods of apnea or suddent death in infants Presentation Symptoms history normal intelligence delayed motor milestones symptoms of spinal stenosis pseudoclaudication and standing discomfort numbness and paresthesias subjective weakness Physical exam rhizomelic dwarfism humerus shorter than forearm and femur shorter than tibia normal trunk adult height ~ 50 inches facial features frontal bossing extremities trident hands (fingers same length with divergent ring and middle fingers) genu varum radial head subluxation muscular hypotonia in infancy spine thoracolumbar kyphosis excessive lordosis Imaging Radiographs lumbar spine findings shortened pedicles decreased interpedicular distance from L1-S1 (pathognomonic) vertebral wedging in thoracolumbar kyphosis posterior vertebral scalloping pelvis and extremities recommended views AP pelvis and weight-bearing hip-to-ankle AP findings champagne glass pelvis (pelvis is wider than deep) Squared iliac wings Inverted V in distal femur physis MRI indications to evaluate spinal stenosis adjunct to sleep study for screening foramen magnum stenosis in infants Treatment - Spine Conditions Thoracolumbar kyphosis nonoperative observation 90% improve bracing if persitent vertebral wedging after age 3 years may be poorly tolerated operative anterior strut corpectomy with posterior fusion or isolated posterior fusion indications bracing has failed kyphosis of > 45-60° Lumbar stenosis nonoperative weight loss, physical therapy, corticosteroid injections indications first line of treatment and frequently effective operative multilevel laminectomy and fusion indications spinal stenosis with severe symptoms nonoperative management has failed Lumbar hyperlordosis nonoperative observation treatment typically not required Foramen magnum stenosis operative surgical decompression of foramen magnum indications sleep apnea or cord compression Treatment - Extremity Conditions Genu varum operative tibial +/- femur osteotomies (based on CORA) indications pain or fibular thrust progressive deformity Short stature operative lower limb lengthening indications (very controversial) feasible due to soft tissue redundancy upper extremity lengthening indications upper extremity lengthening required to maintain ADL's Complications
QUESTIONS 1 of 17 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ12.82) Which of the following radiographs represents the condition associated with the genetic mutation G380R in the transmembrane domain of fibroblast growth factor receptor 3 (FGFR3)? Review Topic QID: 4442 FIGURES: A B C D E 1 Figure A 5% (219/4359) 2 Figure B 6% (281/4359) 3 Figure C 75% (3269/4359) 4 Figure D 10% (426/4359) 5 Figure E 2% (103/4359) ML 2 Select Answer to see Preferred Response PREFERRED RESPONSE 3 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ06.139) A 7-year-old presents to your office for general orthopedic evaluation at the request of his primary care physician. A clinical picture of the patient with his taller sibling is shown in Figure A. What physeal zone is affected by the mutation leading to this patient's condition? Review Topic QID: 325 FIGURES: A 1 Zone of hypertrophy 25% (698/2809) 2 Reserve zone 1% (40/2809) 3 Zone of proliferation 72% (2022/2809) 4 Primary spongiosa 1% (28/2809) 5 Secondary spongiosa 0% (6/2809) ML 2 Select Answer to see Preferred Response PREFERRED RESPONSE 3 (OBQ09.10) Which of the following conditions is associated with a mutation in fibroblast growth factor receptor-3 (FGFR3)? Review Topic QID: 2823 1 Marfan syndrome 2% (25/1154) 2 Gaucher's disease 0% (1/1154) 3 Fibrous dysplasia 4% (49/1154) 4 Achondroplasia 92% (1057/1154) 5 Diastrophic dysplasia 2% (22/1154) ML 1 Select Answer to see Preferred Response PREFERRED RESPONSE 4 (OBQ10.161) Dwarfism caused by a defect of fibroblast growth factor receptor-3 (FGFR3) is associated with all of the following traits EXCEPT: Review Topic QID: 3254 1 Rhizomelic limb shortening 8% (213/2785) 2 Normal intelligence 4% (104/2785) 3 Frontal bossing 4% (109/2785) 4 Cervical spine instability 75% (2089/2785) 5 Spinal stenosis 10% (268/2785) ML 2 Select Answer to see Preferred Response PREFERRED RESPONSE 4 (OBQ06.226) Achondroplasia results from abnormal chondrocyte function in the physis. What receptor is defective and what region of the physis is affected? Review Topic QID: 237 1 FGFR-3, zone of proliferation 77% (813/1054) 2 FGFR-2, zone of proliferation 5% (56/1054) 3 FGFR-3, zone of hypertrophy 15% (160/1054) 4 FGFR-2, zone of hypertrophy 2% (21/1054) 5 COMP, zone of hypertrophy 0% (2/1054) ML 2 Select Answer to see Preferred Response PREFERRED RESPONSE 1 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK
Login to View Community Videos Login to View Community Videos 12th International Congress on Early Onset Scoliosis - 2018 Achondroplasia in 2018 - Paul Sponseller, MD (ICEOS 2018, #57) Pediatrics - Achondroplasia 2/9/2019 38 views