Subtrochanteric Fracture

Subtrochanteric fractures occur within the proximal 5 cm of femoral shaft below the lesser trochanter. This region is subject to extreme mechanical forces — high compressive stress medially and high tensile stress laterally — making it one of the most challenging areas of the femur to fix. They occur in two populations: high-energy trauma in younger patients, and low-energy or even atypical fractures in older patients on long-term bisphosphonate therapy.

Upper thigh pain, inability to bear weight, and thigh swelling. AP pelvis and full-length femur X-rays are mandatory. CT scan helps delineate comminuted fragments. Contralateral femur X-ray is taken to check for bisphosphonate-related stress reaction on the other side.

Nearly all subtrochanteric fractures are treated surgically. The goal is stable fixation that allows early mobilization.

External patient-education references and related OSI pages for additional background:

• Britannica — Bone disease (fractures)
• Britannica — Hip (anatomy)
• AAOS OrthoInfo — patient education library
• OSI glossary — orthopedic terminology in plain language