Menu

Question 6901

Topic: Knee Sports
A 30-year-old sustains a full-thickness articular cartilage defect of the medial femoral condyle. Microfracture is performed to promote healing. The resulting repair tissue that eventually fills the defect relies primarily on which collagen type?
. Type I collagen
. Type II collagen
. Type III collagen
. Type IX collagen
. Type X collagen

Correct Answer & Explanation

. Type I collagen


Explanation

Microfracture penetrates the subchondral bone to release marrow elements, leading to the formation of a fibrocartilage clot. Unlike native hyaline articular cartilage (which is rich in Type II collagen), the resulting fibrocartilage is primarily composed of Type I collagen and has inferior wear properties.

Question 6902

Topic: Knee Sports

Which of the following structures is considered the primary static stabilizer to external tibial rotation at 30 degrees of knee flexion?

. Anterior cruciate ligament
. Posterior cruciate ligament
. Popliteofibular ligament
. Lateral collateral ligament
. Popliteus tendon

Correct Answer & Explanation

. Popliteofibular ligament


Explanation

The popliteofibular ligament (PFL), along with the popliteus tendon and the lateral collateral ligament (LCL), forms the primary components of the posterolateral corner (PLC) of the knee. The PFL and popliteus tendon are the primary stabilizers to external rotation, particularly evaluated at 30 degrees of flexion, whereas the LCL is the primary restraint to varus stress.

Question 6903

Topic: Shoulder & Hip Sports

The 'horn blower's sign' (Patte's test) is used during a physical examination to evaluate the integrity of which of the following rotator cuff muscles?

. Supraspinatus
. Infraspinatus
. Teres minor
. Subscapularis
. Teres major

Correct Answer & Explanation

. Teres minor


Explanation

The horn blower's sign evaluates the teres minor. It is positive when the patient is unable to hold the arm in external rotation with the shoulder abducted to 90 degrees and the elbow flexed to 90 degrees. A positive sign indicates a massive rotator cuff tear involving the teres minor.

Question 6904

Topic: Knee Sports

During an anterior cruciate ligament (ACL) reconstruction, the surgeon elects to drill the femoral tunnel independently through an anteromedial (AM) portal rather than using a transtibial technique. Which of the following is the primary biomechanical advantage of the AM portal technique?

. More vertical graft orientation
. Shorter tibial tunnel length
. Improved rotational stability
. Decreased risk of posterior wall blowout
. Elimination of the need for suspensory fixation

Correct Answer & Explanation

. Improved rotational stability


Explanation

Drilling the femoral tunnel through an anteromedial portal allows for anatomic placement of the femoral footprint (lower and further posterior in the notch with the knee in hyperflexion). This creates a more oblique graft orientation, which is biomechanically proven to better restore rotational stability compared to the vertical graft orientation typically resulting from a transtibial approach.

Question 6905

Topic: Shoulder & Hip Sports

A 24-year-old overhead athlete undergoes surgical stabilization for recurrent anterior shoulder instability. The surgeon performs a 'Remplissage' procedure to address a large, engaging Hill-Sachs defect. This procedure involves the capsulotenodesis of which structure into the humeral defect?

. Supraspinatus tendon
. Subscapularis tendon
. Infraspinatus tendon
. Long head of the biceps tendon
. Coracoacromial ligament

Correct Answer & Explanation

. Infraspinatus tendon


Explanation

The Remplissage procedure (French for 'filling') addresses an off-track or engaging Hill-Sachs lesion by suturing the posterior joint capsule and the infraspinatus tendon into the humeral head defect, preventing the defect from engaging the anterior glenoid rim during external rotation and abduction.

Question 6906

Topic: Knee Sports

A 45-year-old active male presents with medial compartment knee osteoarthritis and varus malalignment. He is being considered for a high tibial osteotomy (HTO). Which of the following preoperative clinical findings is generally considered an absolute contraindication for performing an HTO?

. Age greater than 40 years
. A flexion contracture of 20 degrees
. Intact anterior cruciate ligament (ACL)
. Body Mass Index (BMI) of 28
. Range of motion from 0 to 120 degrees

Correct Answer & Explanation

. A flexion contracture of 20 degrees


Explanation

High Tibial Osteotomy (HTO) relies on redistributing weight-bearing forces to the relatively preserved lateral compartment. Absolute contraindications typically include inflammatory arthritis, a flexion contracture greater than 15 degrees, knee flexion less than 90 degrees, severe patellofemoral arthritis, and significant instability (unless concurrently addressed). A 20-degree flexion contracture prevents normal gait biomechanics and results in poor outcomes post-HTO.

Question 6907

Topic: Shoulder & Hip Sports

A 24-year-old rugby player undergoes evaluation for recurrent anterior shoulder instability. Advanced imaging reveals a large 'engaging' Hill-Sachs lesion and a glenoid bone loss measured at 28%. What is the most appropriate surgical intervention?

. Arthroscopic Bankart repair with capsular shift
. Arthroscopic remplissage alone
. Open inferior capsular shift without osseous transfer
. Latarjet procedure (coracoid transfer)
. Thermal capsulorrhaphy

Correct Answer & Explanation

. Latarjet procedure (coracoid transfer)


Explanation

Glenoid bone loss exceeding critical thresholds (traditionally cited as 20-25%, though some recent literature suggests >13.5-15% in high-risk athletes) is a contraindication to an isolated soft-tissue Bankart repair due to unacceptably high recurrence rates. A Latarjet procedure (transfer of the coracoid process with the attached conjoint tendon to the anterior glenoid neck) restores the osseous arc and provides a 'sling' effect, making it the procedure of choice for massive glenoid bone loss.

Question 6908

Topic: 5. Sports Medicine

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

. Initial necrosis phase (0-4 weeks)
. Revascularization and cellular proliferation phase (6-12 weeks)
. Early remodeling phase (3-6 months)
. Late remodeling phase (6-12 months)
. Maturation phase (1-2 years)

Correct Answer & Explanation

. Revascularization and cellular proliferation phase (6-12 weeks)


Explanation

An ACL autograft undergoes histologic phases: necrosis, revascularization/proliferation, remodeling, and maturation. The graft is structurally at its weakest during the revascularization and cellular proliferation phase (typically between 6 and 12 weeks postoperatively) because the initial necrotic collagen framework is being broken down by enzymes before new organized collagen can mature.

Question 6909

Topic: Knee Sports

During the physical examination of a 22-year-old athlete, the Dial test demonstrates 15 degrees of increased external rotation at 30 degrees of knee flexion compared to the contralateral side, but symmetric external rotation at 90 degrees. Which structure is most likely injured?

. Posterolateral corner (PLC) only
. Posterior cruciate ligament (PCL) only
. Both PLC and PCL
. Anterior cruciate ligament (ACL) only
. Medial collateral ligament (MCL)

Correct Answer & Explanation

. Posterolateral corner (PLC) only


Explanation

The Dial test evaluates external rotation of the tibia. Increased external rotation (>10 degrees compared to the normal side) at 30 degrees only indicates an isolated posterolateral corner (PLC) injury. Increased external rotation at both 30 and 90 degrees indicates injury to both the PLC and the PCL.

Question 6910

Topic: Shoulder & Hip Sports

A 22-year-old baseball pitcher presents with posterior shoulder pain during the late cocking phase of throwing. MRI arthrogram reveals a 'peel-back' lesion of the superior labrum. What is the primary pathophysiologic mechanism of internal impingement in this athlete?

. Impingement of the supraspinatus against the coracoacromial arch
. Contact between the greater tuberosity and the posterosuperior glenoid
. Traction injury to the long head of the biceps tendon
. Contracture of the anteroinferior capsule
. Scapular dyskinesia causing subcoracoid impingement

Correct Answer & Explanation

. Contact between the greater tuberosity and the posterosuperior glenoid


Explanation

Internal impingement in overhead athletes occurs in extreme abduction and external rotation (late cocking phase). The undersurface of the posterior rotator cuff becomes impinged (pinched) between the greater tuberosity of the humeral head and the posterosuperior glenoid labrum, often causing SLAP lesions and partial articular-sided cuff tears.

Question 6911

Topic: 5. Sports Medicine

When comparing freeze-dried (lyophilized) cortical allograft to fresh-frozen cortical allograft, which of the following statements is true regarding the freeze-dried allograft?

. It has a higher risk of viral disease transmission
. It provides superior structural and biomechanical strength
. It elicits a weaker host immune response
. It is intensely osteoinductive
. It contains viable osteoprogenitor cells

Correct Answer & Explanation

. It elicits a weaker host immune response


Explanation

Freeze-drying (lyophilization) depletes major histocompatibility complex (MHC) antigens, significantly decreasing the immunogenicity of the allograft. However, this process alters the physical properties of the bone, markedly reducing its structural and biomechanical strength compared to fresh-frozen allografts. Neither graft contains viable osteoprogenitor cells.

Question 6912

Topic: 5. Sports Medicine

During an anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone autograft, the surgeon inadvertently places the femoral tunnel too anteriorly. What is the most likely clinical consequence of this technical error?

. Knee stiffness in full extension
. Tightness of the graft in flexion causing loss of flexion
. Laxity of the graft in flexion
. Graft impingement on the PCL
. Patellar fracture

Correct Answer & Explanation

. Tightness of the graft in flexion causing loss of flexion


Explanation

An anteriorly placed femoral tunnel creates a graft that is loose in extension and tight in flexion. This typically results in a severe restriction of knee flexion, or graft rupture if forced flexion is attempted.

Question 6913

Topic: Shoulder & Hip Sports

A 22-year-old football player with recurrent anterior shoulder dislocations is found to have 25% bipolar bone loss (glenoid and Hill-Sachs lesion). Which of the following is the most appropriate surgical intervention?

. Arthroscopic Bankart repair
. Arthroscopic SLAP repair
. Latarjet procedure
. Remplissage alone
. Open capsular shift

Correct Answer & Explanation

. Latarjet procedure


Explanation

The Latarjet procedure (coracoid transfer) is indicated for anterior shoulder instability in the setting of critical glenoid bone loss (typically >20-25%). Arthroscopic soft tissue stabilization alone has an unacceptably high failure rate in this scenario.

Question 6914

Topic: 5. Sports Medicine

Which of the following is an inherent biomechanical advantage of using a bone-patellar tendon-bone (BPTB) autograft over a quadruple-stranded hamstring autograft for anterior cruciate ligament (ACL) reconstruction?

. Higher ultimate tensile load of the graft material
. Larger cross-sectional area of the graft
. Bone-to-bone healing within the osseous tunnels
. Decreased incidence of anterior knee pain
. Preservation of the extensor mechanism

Correct Answer & Explanation

. Bone-to-bone healing within the osseous tunnels


Explanation

BPTB autografts allow for rigid osseous fixation and true bone-to-bone healing within the tunnels, which occurs reliably at about 6 weeks. Soft tissue grafts rely on slower Sharpey fiber incorporation, requiring more prolonged biological integration.

Question 6915

Topic: 5. Sports Medicine

A 22-year-old professional soccer player sustains a severe knee injury involving rupture of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and posterolateral corner (PLC). He undergoes staged surgical reconstruction of all ligaments. Which of the following is the most critical factor to consider when determining his readiness for return to professional-level sports?

. Time elapsed since surgery (e.g., 9-12 months).
. Resolution of knee effusion and full range of motion.
. Isokinetic strength testing demonstrating >90% symmetry compared to the contralateral limb.
. Completion of a sport-specific rehabilitation program and passing a functional hop test battery.
. Psychological readiness and absence of fear of re-injury.

Correct Answer & Explanation

. Psychological readiness and absence of fear of re-injury.


Explanation

For high-level professional athletes returning after complex multi-ligament knee reconstruction, psychological readiness is increasingly recognized as a paramount factor, often dictating the success and durability of their return to sport. Even if physical parameters like strength, range of motion, and functional test scores are met, a lingering fear of re-injury, lack of confidence, or an inability to emotionally tolerate the demands of competition can significantly impair performance and increase the risk of re-injury. While time elapsed, resolution of effusion, full range of motion, and objective strength/functional testing are all necessary prerequisites, psychological readiness acts as the gatekeeper for successful and sustainable return to elite-level sports.

Question 6916

Topic: Knee Sports

A 25-year-old soccer player sustains a twisting knee injury. On examination, the dial test shows 15 degrees of increased external rotation at 30 degrees of knee flexion compared to the contralateral side, but symmetric rotation at 90 degrees of flexion. Which structure is most likely injured?

. Anterior cruciate ligament
. Posterior cruciate ligament
. Popliteofibular ligament
. Medial patellofemoral ligament
. Superficial medial collateral ligament

Correct Answer & Explanation

. Popliteofibular ligament


Explanation

An isolated injury to the posterolateral corner (PLC), which includes the popliteofibular ligament, presents with increased external rotation at 30 degrees but not at 90 degrees. Combined PLC and PCL injuries exhibit increased external rotation at both 30 and 90 degrees.

Question 6917

Topic: 5. Sports Medicine

A 19-year-old soccer player undergoes arthroscopy for a bucket-handle medial meniscus tear located in the red-white zone. What is the primary source of blood supply to the peripheral menisci?

. Middle genicular artery
. Medial superior genicular artery
. Lateral inferior genicular artery
. Medial and lateral inferior genicular arteries
. Popliteal artery penetrating branches

Correct Answer & Explanation

. Medial and lateral inferior genicular arteries


Explanation

The peripheral vascular supply of the menisci is provided primarily by the medial and lateral inferior genicular arteries, forming a perimeniscal capillary plexus. This dictates the healing potential of peripheral repairs.

Question 6918

Topic: Shoulder & Hip Sports

A 22-year-old rugby player undergoes preoperative evaluation for recurrent anterior shoulder instability. A 3D-CT scan reveals a large Hill-Sachs lesion. Based on the 'glenoid track' concept, what specific feature categorizes his Hill-Sachs lesion as 'engaging' (off-track)?

. Its lateral margin extends past the lateral border of the footprint
. Its medial margin extends medial to the established glenoid track
. It involves more than 10% of the humeral head articular surface
. It is associated with a concurrent superior labral anterior-posterior (SLAP) tear
. It remains completely lateral to the medial margin of the glenoid track

Correct Answer & Explanation

. Its medial margin extends medial to the established glenoid track


Explanation

An 'engaging' or off-track Hill-Sachs lesion is one where the medial margin of the defect extends medial to the intact glenoid track. This allows the defect to drop over the anterior glenoid rim during abduction and external rotation.

Question 6919

Topic: 5. Sports Medicine

A 28-year-old athlete tears his medial meniscus. An MRI demonstrates the tear is limited to the peripheral 10% of the meniscus, an area known for having excellent healing potential due to its vascularity. This peripheral 'red-red' zone receives its direct vascular supply from the perimeniscal capillary plexus, which originates from the:

. Middle genicular artery
. Popliteal artery
. Medial and lateral superior genicular arteries
. Medial and lateral inferior genicular arteries
. Anterior tibial recurrent artery

Correct Answer & Explanation

. Medial and lateral inferior genicular arteries


Explanation

The peripheral 10-30% of the menisci (the red-red zone) is highly vascularized by the perimeniscal capillary plexus. This plexus is supplied primarily by branches of the medial and lateral inferior genicular arteries.

Question 6920

Topic: 5. Sports Medicine

A 22-year-old female collegiate soccer player undergoes anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone (BPTB) autograft. Compared to a hamstring autograft, the BPTB autograft is most closely associated with an increased incidence of which of the following postoperative complications?

. Increased graft rupture rate
. Anterior knee pain
. Femoral tunnel widening
. Hamstring weakness
. Deep surgical site infection

Correct Answer & Explanation

. Anterior knee pain


Explanation

Bone-patellar tendon-bone (BPTB) autografts provide excellent structural stability but are associated with a higher incidence of donor site morbidity, specifically anterior knee pain and kneeling pain, compared to hamstring autografts.