In a 15-year-old with distal femoral osteosarcoma undergoing limb salvage, the surgical margin requires clearance of the neurovascular bundle. The reconstructive option that best preserves longitudinal growth potential in a skeletally immature patient is:

• A Intercalary allograft with plates
• B Vascularized fibular graft
• C Expandable (growing) endoprosthesis ✓
• D Osteoarticular allograft

Explanation

In skeletally immature patients requiring distal femoral resection, standard endoprostheses cause limb-length discrepancy as the contralateral limb continues to grow. An expandable (growing) endoprosthesis allows non-invasive or minimally invasive lengthening to compensate for projected growth, maintaining limb length equality. This is the preferred reconstruction in children with adequate remaining growth. Allograft options are prone to fracture, non-union, and infection, and do not address growth.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.