3.8 of 83 Ratings
Technique guides are not considered high yield topics for orthopaedic standardized exams including ABOS, EBOT and RC.
A 12-year-old boy is evaluated for limb length inequality. He has a history of osteomyelitis of the left distal femur that was successfully treated. He is otherwise healthy with no other past medical history. Standing full length radiographs confirm a limb length discrepancy of 20 millimeters, attributable to differences in the lengths of the femora. Radiographs of the knee show complete closure of the left distal femoral physis with no angular deformity. If left untreated, what is the projected limb length discrepancy at maturity?
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A 12-year-old male patient is scheduled to undergo femoral lengthening. The 2 techniques at your disposal are (1) femoral lengthening along the mechanical axis of the limb with an external fixator, and (2) femoral lengthening along the anatomical axis of the femur with a telescoping nail. What happens to the mechanical axis of the limb when performing these techniques?
There is no mechanical axis deviation in (1), and medial mechanical axis deviation in (2).
There is lateral mechanical axis deviation in (1) and medial mechanical axis deviation in (2).
There is no fixed direction of mechanical axis deviation in either technique.
There is medial mechanical axis deviation in (1) and lateral mechanical axis deviation in (2).
There is no mechanical axis deviation in (1), and lateral mechanical axis deviation in (2).
At what age does longitudinal growth usually arrest in boys at the distal femur physeal growth plate?
A 13-year-old boy presents with a leg-length discrepancy with the right leg shorter than the left. He has normal height for his age and his skeletal age is equal to his chronologic age. History and examination of Tanner staging reveals that he began puberty 1 month ago. His final leg length discrepancy at skeletal maturity is projected to be 4.0cm. Which of the following surgical options is the most appropriate?
Physeal stapling of the medial left tibial and femoral physis now with staged removal of staples at age 16
Immediate lengthening of the right femur with ring external fixator
Epiphysiodesis of the left femur 1 year after the onset of puberty
Epiphysiodesis of the left femur and tibia 6 months from now
Epiphysiodesis of the bilateral femurs and shortening of the left tibia now
A 14-year-old boy sustains a significant distal femoral physeal fracture. Assuming that he has a complete growth arrest, what is the predicted leg length discrepency?
An 8-year-old girl was treated for a Salter-Harris type I fracture of the right distal femur 2 years ago. Examination reveals symmetric knee flexion, extension, and frontal alignment compared to the contralateral knee. She has 1-cm of shortening of the right femur. History reveals that she has always been in the 50th percentile for height, and her skeletal age matches her chronologic age. Radiographs are shown in Figure 9. What is the expected consequence at maturity?
7-cm limb-length discrepancy with the right femur longer
7-cm limb-length discrepancy with the left femur longer
12-degree varus deformity
18-degree valgus deformity
20-degree recurvatum deformity
A teenager is undergoing a correction of deformity and lengthening of the femur. Distractions are proceeding as expected; however, during his 6-week follow-up examination, the patient reports that the distraction motors have become harder to turn over for the past 2 to 3 days. Figures 37a and 37b show current radiographs. What is the most likely complication being encountered?
Poor regenerate bone formation
A 14-year-old boy undergoes application of a circular frame with tibial and fibular osteotomy for gradual limb lengthening. He initiates lengthening 7 days after surgery. During the first week of lengthening, he reports that turning of the distraction devices is becoming increasingly difficult. On the 9th day of lengthening, he is seen in the emergency department after feeling a pop in his leg and noting the acute onset of severe pain. What complication has most likely occurred?
Joint subluxation and acute ligament rupture
Incomplete corticotomy at the time of surgery with spontaneous completion and acute distraction
Premature consolidation of the osteotomy with breakage of bone transfixation wire
Fracture through the bone regenerate
Fracture of the tibia through a unicortical half-pin track
Which of the following is considered the best method to measure limb-length discrepancy in a patient with a knee flexion contracture?
Obtain a standard scanogram
Obtain a lateral CT scanogram
Measure the distance from the anterior superior iliac spine to the medial malleolus
Measure the distance from the umbilicus to the medial malleolus
Stand the patient on blocks to measure the difference in the heights of the iliac wings
A 9-year-old male sustains the fracture seen in Figure A. If a complete growth arrests occurs, his expected leg length discrepancy at skeletal maturity would be?
A 14-year-old male patient with a leg-length discrepancy undergoes a distal femoral and proximal tibial epiphysiodesis on the longer leg. What is the anticipated amount of correction achieved with this procedure in this child?
A 9-year-old girl presents with a history of juvenile rheumatoid arthritis, and a 20 degree flexion contracture of her left knee. A clinical photo is shown in Figure A. Which of the following is the most accurate method of determining leg length discrepancy in this patient?
A 17-year-old female presents for evaluation of a limb length discrepancy. While standing, a 10mm block is placed under her short leg resulting in a leveled pelvis. She has no lower extremity contractures. Which of the following next steps would be most appropriate following her initial screening?
Perform a CT scanogram
Epiphysiodesis of the longer limb
Femoral lengthening of the shorter limb
Physeal bar excision
A 14-year-old boy has complete growth arrest of his left proximal tibia after a skateboarding injury. He currently has a 3mm leg-length discrepancy with left shorter than the right. A radiograph of the patients left hand, wrist, and fingers demonstrate a bone-age of 14 years. What is the most appropriate management of this patient?
Left tibial lengthening
Right tibia epiphysiodesis
Right femur epiphysiodesis