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Question 6921

Topic: 5. Sports Medicine

Following an anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone autograft, the graft undergoes a process of 'ligamentization'. During which phase is the graft mechanically at its weakest?

. Inflammatory phase (0-4 weeks)
. Early remodeling phase (6-12 weeks)
. Proliferation phase (3-4 weeks)
. Maturation phase (1-2 years)
. The graft strength remains constant post-fixation

Correct Answer & Explanation

. Early remodeling phase (6-12 weeks)


Explanation

The remodeling phase (often termed the necrotic or revascularization phase initially, transitioning to remodeling) occurs roughly 6 to 12 weeks post-operatively. During this time, the graft undergoes necrosis and revascularization, resulting in the lowest mechanical strength before fibroblasts lay down new collagen and maturation occurs.

Question 6922

Topic: Shoulder & Hip Sports

A 22-year-old rugby player has suffered multiple anterior shoulder dislocations. Pre-operative advanced imaging demonstrates 25% anterior glenoid bone loss. Which of the following surgical procedures is most appropriate to minimize recurrence?

. Arthroscopic Bankart repair
. Open capsular shift
. Latarjet procedure
. Remplissage
. Superior labrum anterior-posterior (SLAP) repair

Correct Answer & Explanation

. Latarjet procedure


Explanation

Significant anterior glenoid bone loss (> 20-25%) in the setting of recurrent anterior instability is a contraindication to an isolated soft-tissue repair (Bankart). The Latarjet procedure (coracoid transfer) is the standard of care to restore the osseous arc and provide a sling effect from the conjoined tendon.

Question 6923

Topic: Knee Sports

A 40-year-old male sustains a posterior medial meniscus root tear. Biomechanically, this injury is most equivalent to which of the following?

. A 25% partial meniscectomy
. A 50% partial meniscectomy
. A total meniscectomy
. An anterior horn meniscus tear
. A bucket-handle meniscus tear

Correct Answer & Explanation

. A total meniscectomy


Explanation

A posterior meniscus root tear completely disrupts the hoop stresses of the meniscus, rendering it biomechanically equivalent to a total meniscectomy. This drastically increases peak contact pressures in the compartment, leading to rapid osteoarthritis.

Question 6924

Topic: 5. Sports Medicine

When performing an anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone (BPTB) autograft, which of the following is the most commonly reported long-term complication compared to hamstring autografts?

. Higher rate of graft rupture
. Increased anterior knee pain and pain with kneeling
. Greater incidence of deep vein thrombosis
. Decreased hamstring strength
. Increased risk of postoperative stiffness requiring lysis of adhesions

Correct Answer & Explanation

. Increased anterior knee pain and pain with kneeling


Explanation

Bone-patellar tendon-bone (BPTB) autografts are associated with a significantly higher incidence of donor site morbidity compared to hamstring grafts. This is most frequently manifested as anterior knee pain and discomfort with kneeling.

Question 6925

Topic: 5. Sports Medicine

When evaluating graft choices for anterior cruciate ligament (ACL) reconstruction, how do the biomechanical properties of a 10mm bone-patellar tendon-bone (BPTB) autograft compare to those of the native intact ACL?

. BPTB has a lower ultimate load to failure and lower stiffness
. BPTB has a lower ultimate load to failure but higher stiffness
. BPTB has a higher ultimate load to failure and higher stiffness
. BPTB has an identical ultimate load to failure but lower stiffness
. BPTB has a higher ultimate load to failure but lower stiffness

Correct Answer & Explanation

. BPTB has a higher ultimate load to failure and higher stiffness


Explanation

A 10mm bone-patellar tendon-bone (BPTB) autograft is biomechanically stronger and stiffer than the native ACL. The native ACL has an ultimate load to failure of approximately 2160 N and a stiffness of 242 N/mm. A 10mm BPTB graft has an ultimate load to failure of approximately 2977 N and a stiffness of 620 N/mm. Therefore, it has both higher ultimate load to failure and higher stiffness than the native ACL.

Question 6926

Topic: Shoulder & Hip Sports

A 50-year-old male sustains a traumatic anterior shoulder dislocation. After reduction, he continues to have severe anterior shoulder pain and significant weakness in internal rotation. Examination demonstrates a positive lift-off test. Given this specific injury pattern, which adjacent structure is at the highest risk for subluxation or instability?

. Long head of the biceps tendon
. Short head of the biceps tendon
. Acromioclavicular joint
. Coracoclavicular ligaments
. Suprascapular nerve

Correct Answer & Explanation

. Long head of the biceps tendon


Explanation

The patient has a traumatic subscapularis tear, indicated by weakness in internal rotation and a positive lift-off test. The subscapularis tendon insertion forms the medial wall of the bicipital groove and, together with the coracohumeral ligament, creates the biceps pulley. A tear of the upper border of the subscapularis profoundly destabilizes this pulley system, allowing the long head of the biceps tendon (LHBT) to subluxate or dislocate medially.

Question 6927

Topic: 5. Sports Medicine

Following an anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone (BPTB) autograft, at what time point postoperative is the graft substance structurally at its weakest mechanics due to remodeling?

. 1 to 2 weeks
. 6 to 12 weeks
. 4 to 5 months
. 6 to 8 months
. 12 months

Correct Answer & Explanation

. 6 to 12 weeks


Explanation

The autograft undergoes a process of necrosis, revascularization, and remodeling (ligamentization). During the 6-12 week postoperative window, the graft substance undergoes significant cellular repopulation and collagen remodeling, making it mechanically at its weakest point and most vulnerable to elongation or rupture.

Question 6928

Topic: Shoulder & Hip Sports
A 22-year-old baseball pitcher presents with vague anterior shoulder pain. An MRI arthrogram reveals a SLAP tear. Which type of SLAP lesion involves detachment of both the superior labrum and the origin of the long head of the biceps tendon from the supraglenoid tubercle?
. Type I
. Type II
. Type III
. Type IV
. Type V

Correct Answer & Explanation

. Type II


Explanation

Type II SLAP tears are characterized by the detachment of the superior labrum and the long head of the biceps anchor from the supraglenoid tubercle. Type I is degenerative fraying; Type III is a bucket-handle tear with an intact biceps anchor; Type IV is a bucket-handle tear extending into the biceps tendon.

Question 6929

Topic: Knee Sports

During reconstruction of the anterior cruciate ligament (ACL), the surgeon must be aware of the native ligament's vascular supply to optimize graft incorporation. The primary blood supply to the native ACL arises from which vessel?

. Lateral inferior genicular artery
. Medial inferior genicular artery
. Middle genicular artery
. Descending genicular artery
. Recurrent tibial artery

Correct Answer & Explanation

. Middle genicular artery


Explanation

The primary blood supply to the ACL is the middle genicular artery, which branches from the popliteal artery and pierces the posterior joint capsule to supply the cruciate ligaments.

Question 6930

Topic: Knee Sports
Articular cartilage is primarily composed of water, collagen, and proteoglycans. Which type of collagen constitutes the vast majority of the collagenous framework in normal, healthy adult hyaline articular cartilage?
. Type I
. Type II
. Type III
. Type IV
. Type X

Correct Answer & Explanation

. Type II


Explanation

Type II collagen accounts for 90-95% of the collagen in healthy hyaline articular cartilage, providing its necessary tensile strength. Fibrocartilage, which often forms after microfracture procedures, is predominantly composed of Type I collagen.

Question 6931

Topic: Knee Sports

A 25-year-old skier presents with acute knee swelling after a twisting fall. Plain radiographs reveal an avulsion fracture of the lateral tibial plateau (Segond fracture). This radiographic finding is pathognomonic for an injury to which of the following structures?

. Posterior cruciate ligament
. Anterior cruciate ligament
. Medial collateral ligament
. Posterolateral corner
. Popliteus tendon

Correct Answer & Explanation

. Anterior cruciate ligament


Explanation

A Segond fracture is an avulsion fracture of the anterolateral proximal tibia, representing an avulsion of the anterolateral ligament (ALL) or lateral capsular attachment. It is highly pathognomonic for an anterior cruciate ligament (ACL) tear.

Question 6932

Topic: Shoulder & Hip Sports

A 20-year-old athlete undergoes arthroscopic evaluation for recurrent anterior shoulder instability. An 'engaging' Hill-Sachs lesion is identified. What is the most appropriate concurrent procedure to perform alongside an arthroscopic Bankart repair?

. Latarjet procedure
. Remplissage procedure
. Biceps tenodesis
. Superior capsular reconstruction
. Subscapularis advancement

Correct Answer & Explanation

. Remplissage procedure


Explanation

An engaging Hill-Sachs lesion can lever the humeral head out of the glenoid during external rotation and abduction. The Remplissage procedure, which involves tenodesis of the infraspinatus and capsule into the defect, converts an intra-articular defect into an extra-articular one, preventing engagement.

Question 6933

Topic: Knee Sports

In a posterior-stabilized total knee arthroplasty, the posterior cruciate ligament is sacrificed. What design feature is primarily responsible for substituting the function of the PCL to achieve physiologic femoral rollback during deep flexion?

. The conforming geometry of the anterior tibial polyethylene lip
. The interaction between the femoral cam and the tibial polyethylene post
. The inherent tension of the medial collateral ligament
. An asymmetrical posterior femoral condylar offset
. The preservation of the anterior cruciate ligament

Correct Answer & Explanation

. The interaction between the femoral cam and the tibial polyethylene post


Explanation

In a posterior-stabilized (PS) total knee arthroplasty, the PCL is excised. To replicate the PCL's normal function of causing posterior translation (rollback) of the femur on the tibia during flexion, a cam mechanism on the femoral component engages with a central post on the tibial polyethylene insert. This engagement mechanically forces the femur to roll back as the knee flexes past a certain point, optimizing the extensor mechanism moment arm and improving maximum flexion.

Question 6934

Topic: 5. Sports Medicine

Which of the following commonly utilized grafts for anterior cruciate ligament (ACL) reconstruction demonstrates the highest ultimate load to failure in biomechanical testing compared to the native ACL?

. 10 mm Bone-Patellar Tendon-Bone (BPTB) autograft
. Quadrupled hamstring autograft
. Central third quadriceps tendon autograft
. Fascia lata autograft
. Double-stranded semitendinosus autograft

Correct Answer & Explanation

. Quadrupled hamstring autograft


Explanation

Biomechanical studies have shown that the native ACL has an ultimate load to failure of approximately 2160 N. A quadrupled hamstring graft (double-stranded semitendinosus and gracilis) is the strongest of the standard autografts, with an ultimate load to failure exceeding 4000 N. A 10 mm BPTB graft fails at roughly 2977 N, and a central quadriceps tendon graft at ~2350 N.

Question 6935

Topic: 5. Sports Medicine

A 22-year-old athlete sustains a non-contact pivoting injury to the knee, resulting in an acute anterior cruciate ligament (ACL) rupture. Which of the following is the most commonly associated meniscal injury in the acute setting?

. Medial meniscus posterior horn tear
. Lateral meniscus posterior horn tear
. Medial meniscus bucket-handle tear
. Lateral meniscus anterior horn tear
. Medial meniscus root tear

Correct Answer & Explanation

. Lateral meniscus posterior horn tear


Explanation

In acute ACL ruptures, the lateral meniscus is most commonly torn (specifically the posterior horn) due to the pivot-shift mechanism of injury and the collision of the lateral femoral condyle against the posterolateral tibial plateau. In contrast, chronic ACL deficiency most commonly leads to tears of the posterior horn of the medial meniscus, as it acts as the primary secondary restraint to anterior tibial translation over time.

Question 6936

Topic: Shoulder & Hip Sports

The Instability Severity Index Score (ISIS) is used to predict the risk of recurrent anterior shoulder instability following arthroscopic Bankart repair. Which of the following is NOT a parameter evaluated in the ISIS?

. Age < 20 years at the time of surgery
. Involvement in competitive sports
. Presence of a Hill-Sachs lesion on an AP radiograph
. Presence of an isolated SLAP tear on MRI
. Loss of anterior glenoid contour on an AP radiograph

Correct Answer & Explanation

. Presence of an isolated SLAP tear on MRI


Explanation

The ISIS predicts the risk of recurrent anterior shoulder instability. Parameters include age <20 (2 pts), competitive sports (2 pts), contact/forced overhead sports (1 pt), Hill-Sachs lesion on AP radiograph (2 pts), and glenoid bone loss on AP radiograph (2 pts). A score >6 historically suggested an unacceptably high failure rate for arthroscopic repair, prompting consideration for a Latarjet procedure. A SLAP tear is not a component of the score.

Question 6937

Topic: Knee Sports

Biomechanical studies have demonstrated that a complete posterior root avulsion of the medial meniscus disrupts the circumferential hoop stresses of the knee. This specific injury leads to medial compartment contact pressures most equivalent to which of the following states?

. An intact, healthy meniscus
. A partial meniscectomy removing 50% of the posterior horn
. A total medial meniscectomy
. An isolated anterior cruciate ligament deficiency
. An isolated posterior cruciate ligament deficiency

Correct Answer & Explanation

. A total medial meniscectomy


Explanation

A complete radial tear or root avulsion of the posterior horn of the medial meniscus breaks the continuity of the meniscal ring, completely abolishing its ability to convert axial loads into circumferential hoop stresses. Biomechanically, this results in medial compartment peak contact pressures and kinematics that are completely equivalent to a total meniscectomy, leading to rapid, progressive osteoarthritis if left untreated.

Question 6938

Topic: Knee Sports

A 28-year-old competitive athlete sustains a high-energy knee injury resulting in a knee dislocation with rupture of the ACL, PCL, and posterolateral corner (PLC). Neurovascular examination reveals intact distal pulses and sensation. After emergent reduction, the knee remains grossly unstable. What is the most appropriate surgical management strategy and timing for this patient?

. Acute repair of all ruptured ligaments within 24-72 hours
. Staged reconstruction, with acute repair of the PLC and delayed reconstruction of the ACL/PCL
. Single-stage reconstruction of all ruptured ligaments once swelling subsides (2-3 weeks post-injury)
. Non-operative management with bracing and rehabilitation
. Arthroscopic debridement followed by 6 weeks of immobilization

Correct Answer & Explanation

. Single-stage reconstruction of all ruptured ligaments once swelling subsides (2-3 weeks post-injury)


Explanation

For multi-ligament knee dislocations without vascular compromise, the current consensus typically favors a single-stage, comprehensive reconstruction of all ruptured ligaments. The optimal timing is generally delayed until acute swelling and inflammation have subsided, typically 2-3 weeks post-injury. This allows for better tissue handling, reduced arthrofibrosis risk, and improved surgical outcomes. Acute repair of multiple ligaments often fails due to poor tissue quality and high tension. Staged reconstruction is an option but can be more complex and prolong recovery; single-stage is preferred for efficiency. Non-operative management is usually reserved for very low-demand patients or those with severe comorbidities and is generally not recommended for athletes with significant instability. Arthroscopic debridement alone does not address gross instability.

Question 6939

Topic: Shoulder & Hip Sports

A 22-year-old rugby player has recurrent anterior shoulder instability. CT arthrogram demonstrates 25% anterior glenoid bone loss and an engaging Hill-Sachs lesion. Which of the following surgical procedures is most appropriate?

. Arthroscopic Bankart repair with Remplissage
. Arthroscopic Bankart repair alone
. Latarjet procedure
. Capsular shift
. Putti-Platt procedure

Correct Answer & Explanation

. Latarjet procedure


Explanation

Glenoid bone loss greater than 20-25% in a contact athlete is an absolute indication for a bony augmentation procedure like the Latarjet. Soft tissue repairs alone have an unacceptably high failure rate in this scenario.

Question 6940

Topic: 5. Sports Medicine

A 19-year-old female soccer player undergoes ACL reconstruction using a bone-patellar tendon-bone (BPTB) autograft. Which of the following complications is most specific to this graft choice compared to a hamstring autograft?

. Increased risk of deep vein thrombosis
. Postoperative arthrofibrosis
. Patellar fracture
. Graft tunnel mismatch
. Saphenous nerve injury

Correct Answer & Explanation

. Patellar fracture


Explanation

Patellar fracture is a recognized, specific complication of the BPTB autograft due to the harvest of the bone block from the patella. Hamstring grafts have a higher association with saphenous nerve neuropathy.