Lower Extremity Trauma MCQs

A 40-year-old male presents with post-traumatic deformity. Standing radiographs show a lateral Mechanical Axis Deviation (MAD). Measurement of the mechanical Lateral Distal Femoral Angle (mLDFA) is 80 degrees, while the MPTA is 87 degrees. Based on Paley's normal parameters, what is the primary deformity?

During preoperative planning for a sagittal plane tibial deformity, the Posterior Proximal Tibial Angle (PPTA) is measured. The normal anatomic PPTA is approximately 81 degrees. If a patient has a PPTA of 95 degrees, what type of deformity is present?

In the context of the Fixator-Assisted Nailing (FAN) technique, which of the following is an absolute contraindication to utilizing this method for deformity correction?

When calculating the magnitude of translation generated by applying Paley's Rule 2 (ACA at CORA, osteotomy distant from CORA), the amount of translation is mathematically dependent on which two factors?

A 45-year-old patient presents with medial knee pain. Standing long-leg radiographs reveal a Mechanical Axis Deviation (MAD) of 35 mm medial to the midline. The Mechanical Proximal Tibial Angle (MPTA) is 87 degrees, the mechanical Lateral Distal Femoral Angle (mLDFA) is 96 degrees, and the Joint Line Convergence Angle (JLCA) is 1 degree. Where is the primary source of the patient's deformity?

A surgeon is evaluating a patient for a sagittal plane deformity of the proximal tibia prior to an osteotomy. What is the normal accepted range for the Posterior Proximal Tibial Angle (PPTA)?

A surgeon utilizes the Fixator-Assisted Nailing (FAN) technique to correct a severe distal tibial varus deformity. To guide the intramedullary nail and prevent recurrent deformity, blocking (Poller) screws are planned. Where must the blocking screws be placed relative to the medullary canal to achieve optimal correction?

Evaluation of sagittal plane alignment is crucial prior to proximal tibial osteotomy to avoid inadvertently altering knee kinematics. What is the approximate normal value for the posterior proximal tibial angle (PPTA)?

When executing a malalignment test on a standing full-length radiograph, the mechanical lateral distal femoral angle (mLDFA) is precisely measured. Which of the following correctly defines the mLDFA?

A 48-year-old patient presents with a symptomatic genu varum deformity and confirmed significant lateral collateral ligament (LCL) laxity, leading to a varus thrust. Following the Paley Method, the orthopedic surgeon plans a proximal tibial osteotomy. What is the primary biomechanical rationale for intentionally overcorrecting the limb into 3 to 5 degrees of mechanical tibiofemoral valgus in this specific scenario?

A 68-year-old female presents with severe medial compartment osteoarthritis, a 20mm medial Mechanical Axis Deviation (MAD), and a 7° laterally open Joint Line Convergence Angle (JLCA) on weight-bearing radiographs. She also exhibits a significant varus thrust during gait. Based on the Paley Method, what is the most appropriate surgical strategy to address both the bony malalignment and the ligamentous laxity?

A 30-year-old male presents with a chronic varus knee deformity and a history of a prior lateral knee injury. His standard double-leg stance long-leg radiograph shows a relatively well-aligned mechanical axis. However, a single-leg stance radiograph of the affected limb reveals a significant medial shift of the Mechanical Axis Deviation (MAD) and an increased Joint Line Congruency Angle (JLCA). What is the most critical implication of these findings for surgical planning?

A 45-year-old male has a Mechanical Axis Deviation (MAD) of 30 mm medial to the knee center. His mechanical lateral distal femoral angle (mLDFA) is 88 degrees, and his medial proximal tibial angle (MPTA) is 80 degrees. Where is the primary site of the structural varus deformity?

When planning a high tibial osteotomy for medial compartment osteoarthritis in a varus knee, the traditional target for the new mechanical axis is the Fujisawa point. Where is this point anatomically located on the tibial plateau?

A patient undergoes Paley method evaluation for varus malalignment. The surgeon decides to measure the Joint Line Convergence Angle (JLCA) to evaluate soft tissue contributions. Which anatomical landmarks define the JLCA?

A 30-year-old male with symptomatic genu varum is found to have an mLDFA of 95 degrees and an MPTA of 88 degrees. What is the primary anatomic source of his mechanical axis deviation?

A 50-year-old female presents with severe right knee varus. Her standing full-length radiographs demonstrate a mechanical axis deviation (MAD) of 45 mm medial to the center of the knee. The mechanical lateral distal femoral angle (mLDFA) is 88 degrees, and the medial proximal tibial angle (MPTA) is 75 degrees. What is the primary source of her varus deformity?

A patient with profound medial compartment osteoarthritis and varus thrust is planned for deformity correction. The surgeon notes that correcting the entire deformity through a single proximal tibial osteotomy would result in a medial proximal tibial angle (MPTA) of 98 degrees. What is the most appropriate surgical strategy according to Paley's principles?

During the Paley malalignment test for a patient with severe genu varum,

you note the mechanical axis line falls entirely medial to the medial tibial plateau. If the MPTA is 80 degrees and the mLDFA is 88 degrees, where does the center of rotation of angulation (CORA) lie?

When planning a high tibial osteotomy (HTO) for medial compartment osteoarthritis with a varus deformity, the mechanical axis is typically shifted slightly laterally. According to the Paley method and classic literature, the target correction point (the Fujisawa point) is located at approximately what percentage of the tibial plateau width from the medial edge?