MCQ – 91784

Fracture at which site affects the longitudinal growth of a bone?

Correct Answer » A Explanation

–Clinical Reasoning for the Correct Answer:
– The epiphyseal plate (also known as the growth plate or physis) is the site where new bone is produced during growth.
– Damage to the epiphyseal plate can disrupt endochondral ossification, leading to impaired or asymmetric longitudinal bone growth.

Why Option A (Epiphyseal plate) is correct:
– Directly responsible for longitudinal bone growth in children/adolescents.
– Injury can cause premature closure or growth disturbance.

Why Option B (Diaphysis) is incorrect:
– Diaphysis = shaft of the long bone; primarily involved in appositional (width) growth and mechanical strength.
– Fractures here do not disrupt longitudinal growth unless vascular supply to the physis is compromised.
– Examples of diaphyseal fractures: mid-shaft femur, humerus.

Why Option C (Epiphysis) is incorrect:
– Epiphysis = end of the long bone, where articular cartilage is located.
– While close to the growth plate, isolated epiphyseal fractures may not affect the physis unless the plate itself is involved.
– Epiphyseal injuries can cause joint surface problems if the articular surface is disrupted.

Why Option D (Metaphysis) is incorrect:
– Metaphysis = flared region just adjacent to the growth plate.
– Rich in blood supply; common site for some pediatric fractures (e.g., supracondylar humerus).
– Fractures here do not typically cross into or damage the physis itself.

High‑Yield Synopsis:

Etiology & Pathogenesis
– Epiphyseal plate = specialized cartilage for longitudinal bone growth in children/adolescents
– Fractures involving physis → disruption of endochondral ossification → growth arrest/deformity risk

Clinical Features
– Growth plate injuries (Salter-Harris fractures) most common in pediatric populations
– Possible leg length discrepancy or angular deformity if physis is damaged

Differential Diagnoses
– Metaphyseal fracture: No longitudinal growth disturbance unless physis involved
– Diaphyseal fracture: No growth disturbance
– Epiphyseal fracture: May affect joint, less often growth

Diagnostic Findings
– Radiographs detect physeal widening, displacement, or fracture lines through the physis
– MRI can delineate growth plate injury if X-ray unclear

Management & Prognosis
– Accurate anatomic reduction crucial in physeal fractures
– Risk: Growth disturbance, especially with higher-grade Salter-Harris types
– Early orthopedic intervention reduces risk of limb length discrepancy