Fracture Neck of Femur (Intracapsular)
Fracture of the Femoral Neck is the "Unsolved Fracture." It is intracapsular (inside the joint capsule), meaning the fracture line cuts off the blood supply to the femoral head, creating a high risk of non-union and AVN.
1. The Vascular Problem
The femoral head is supplied by the Retinacular Vessels (branches of the Medial Circumflex Femoral Artery). A displaced fracture tears these vessels, starving the head.
2. Garden Classification
- Type I: Incomplete/Impacted (Valgus). Stable.
- Type II: Complete but Undisplaced. Stable.
- Type III: Complete and Partially Displaced.
- Type IV: Complete and Fully Displaced. (Highest AVN risk).
3. Management Algorithm
- Undisplaced (Garden I/II): Fixation with Cannulated Cancellous Screws (CCS). Preserve the head.
- Displaced (Garden III/IV) in Young (<60): Urgent Reduction + Fixation (DHS/Screws). Try to save the head.
- Displaced (Garden III/IV) in Elderly (>60): Replace the head.
- Active Elderly: Total Hip Replacement (THR).
- Low Demand/Frail: Hemiarthroplasty (Austin Moore/Bipolar).
25 Practice MCQs
Q1. Which artery provides the main blood supply to the femoral head?
Answer: A). Specifically the lateral epiphyseal branch.
Q2. Intracapsular fractures have a high risk of:
Answer: A). Due to lack of periosteum (no callus) and vascular damage.
Q3. Garden Type I is:
Answer: A). The most stable type.
Q4. Clinical presentation of displaced NOF fracture:
Answer: A). Psoas pulls it short; Gravity/Glutes rotate it out.
Q5. Treatment for Garden III/IV in a 75-year-old patient:
Answer: A). Fixation has a high failure rate; replacement allows immediate walking.
Q6. The Pauwels Classification is based on:
Answer: A). Type III (Vertical) is most unstable due to shear forces.
Q7. Why is cambium layer of periosteum absent in the neck?
Answer: A). Healing must be by primary union (contact healing).
Q8. Hemiarthroplasty involves replacing:
Answer: A). The acetabulum is left native.
Q9. Treatment for Garden I/II in a young patient:
Answer: A). Fix "in situ" to prevent displacement.
Q10. Ward's Triangle is:
Answer: A). Makes it prone to fracture.
Q11. The "Golden Window" for fixing a young neck femur fracture to save the head is:
Answer: A). Urgent reduction improves blood flow.
Q12. Austin Moore Prosthesis is:
Answer: A). Has holes in the stem for bone ingrowth (fenestrated).
Q13. Bipolar Hemiarthroplasty differs from Monopolar because:
Answer: A). Less erosion of the patient's cartilage.
Q14. Trendelenburg Gait post-surgery is due to weakness of:
Answer: A). Especially if Lateral approach was used.
Q15. Subcapital fracture is located:
Answer: A). Worst prognosis.
Q16. Can a patient walk with an impacted (Garden I) fracture?
Answer: A). Dangerous as it can displace later ("Secondary displacement").
Q17. Which position is avoided after Posterior Approach Hip Arthroplasty?
Answer: A). Risk of posterior dislocation.
Q18. A "Stress Fracture" of the femoral neck is seen in:
Answer: A). Repetitive loading.
Q19. Singh Index grades:
Answer: A). Grade 6 is normal, Grade 1 is severe.
Q20. Capsulotomy is done during fixation to:
Answer: A). Tamponade effect can kill the head.
Q21. Basicervical fracture behaves like:
Answer: A). Base of neck, better blood supply.
Q22. 1-year mortality rate after hip fracture in elderly is approx:
Answer: A). Due to DVT, PE, pneumonia, comorbidities.
Q23. Cement Bone Implantation Syndrome leads to:
Answer: A). Embolization of marrow contents.
Q24. Full weight bearing is allowed after Hemiarthroplasty:
Answer: A). The implant is stable. Early mobilization saves lives.
Q25. "Crescent Sign" on X-ray indicates:
Answer: A). Late sign of failure.
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