Inter-trochanteric Fractures (IT Fracture)
IT fractures occur between the Greater and Lesser Trochanters. Unlike neck fractures, these are extracapsular. They heal very well due to rich cancellous bone blood supply, but malunion (Varus) is common.
1. Evans Classification
- Stable: Posteromedial cortex is intact. 2-part fractures.
- Unstable: Posteromedial cortex comminution, Reverse Obliquity, or 4-part fractures. The "Lesser Trochanter" is the key to stability.
2. Clinical Features
- Leg is Shortened and in External Rotation (often 90 degrees, unlike neck fracture which is ~45 degrees due to capsule limits).
- Significant bruising/swelling (extracapsular bleeding).
3. Management
- DHS (Dynamic Hip Screw): For stable fractures. Allows controlled collapse (compression) of the fracture.
- PFN (Proximal Femoral Nail): Intramedullary nail. Gold standard for Unstable or Reverse Oblique fractures.
25 Practice MCQs
Q1. Intertrochanteric fractures are:
Answer: A). Non-union is rare; Malunion is the issue.
Q2. The most important structure determining stability is:
Answer: B). If the buttress is gone, the fracture collapses into varus.
Q3. The limb attitude in IT fracture is:
Answer: A). The capsule does not restrict the rotation (extracapsular).
Q4. DHS (Dynamic Hip Screw) works on the principle of:
Answer: A). The screw slides in the barrel as bone resorbs, maintaining contact.
Q5. Reverse Obliquity fractures are best treated with:
Answer: A). DHS causes the shaft to slide laterally in reverse patterns (failure).
Q6. Coxa Vara malunion leads to:
Answer: A). Neck-shaft angle < 120 degrees.
Q7. Tip-Apex Distance (TAD) should be:
Answer: A). To prevent screw "Cut-out" through the femoral head.
Q8. Evans Classification is based on:
Answer: A). Stable vs Unstable.
Q9. Which muscle attaches to the Lesser Trochanter?
Answer: A). Pulls the fragment proximally.
Q10. Which muscle attaches to the Greater Trochanter?
Answer: A). And external rotators.
Q11. Is AVN a common complication of IT fractures?
Answer: B). Blood supply is usually intact.
Q12. The Z-effect is a complication of:
Answer: A). One screw backs out, the other migrates in.
Q13. PFN (Proximal Femoral Nail) is biomechanically superior because:
Answer: A). It sits closer to the weight-bearing axis.
Q14. "Lateral Wall Blowout" makes which implant unstable?
Answer: A). The barrel loses support.
Q15. Mortality rate is similar to Neck of Femur fractures. True/False?
Answer: A). Due to patient age and comorbidities.
Q16. Blood loss in IT fracture vs Neck fracture:
Answer: A). Can lose > 1 liter into the thigh.
Q17. Subtrochanteric extension of the fracture requires:
Answer: A). To bypass the fracture line and stress riser.
Q18. Weight bearing after PFN fixation is:
Answer: A). Key advantage for elderly.
Q19. Derotation screw helps to:
Answer: A). Used in some nail systems.
Q20. External Rotation deformity is caused by:
Answer: A). Typical posture.
Q21. Basicervical fracture behaves like:
Answer: A). Transitional zone.
Q22. "Cut-out" refers to:
Answer: A). Due to poor positioning (high TAD) or poor bone quality.
Q23. A "Shortening" of 1-2 cm after DHS fixation is:
Answer: A). Compression aids healing.
Q24. An elderly patient with severe arthritis AND an IT fracture should get:
Answer: A). Solves both problems.
Q25. Heterotopic ossification is common?
Answer: B). Unless abductor muscles are severely traumatized.
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