1. Femoral Neck Fractures

2. Anatomy Physeal closure age 16 Neck-shaft angle 130° ± 7° Anteversion 10° ± 7° Calcar Femorale Posteromedial dense plate of bone

3. Blood Supply Lateral epiphysel artery –terminal branch MFC artery –predominant blood supply to weight bearing dome of head Artery of ligamentum teres –from obturator artery –supplies anteroinferior head Lateral femoral circumflex a. –less contribution than MFC

4. Blood Supply Greater fracture displacement = greater risk of vascular disruption to femoral head revascularization of the head – intact vessels –vascular ingrowth across fracture site importance of quality of reduction –metaphyseal vessels

5. Epidemiology 250,000 Hip fractures annually –Expected to double by 2050 At risk populations –Elderly: poor balance & vision, osteoporosis, inactivity, medications, malnutrition incidence doubles with each decade beyond age 50 –higher in white population –Other factors: smokers, small body size, excessive caffeine –Young: high energy trauma

6. Classification Pauwels [1935] –Angle describes vertical shear vector

7. Classification Garden [1961] I Valgus impacted or incomplete II Complete Non-displaced III Complete Partial displacement IV Complete Full displacement ** Portends risk of AVN and Nonunion I II III IV

8. Classification Functional Classification –Stable Impacted (Garden I) Non-displaced (Garden II) –Unstable Displaced (Garden III and IV)

9. Treatment Goals –Improve outcome over natural history –Minimize risks and avoid complications –Return to pre-injury level of function –Provide cost-effective treatment

10. Treatment Options –Non-operative very limited role Activity modification Skeletal traction –Operative ORIF Hemiarthroplasty Total Hip Replacement

11. Treatment Decision Making Variables Patient Characteristics –Young (arbitrary physiologic age < 65) High energy injuries –Often multi-trauma High Pauwels Angle (vertical shear pattern) –Elderly Lower energy injury Comorbidities Pre-existing hip disease Fracture Characteristics –Stable –Unstable

12. Treatment Young Patients (Arbitrary physiologic age < 65) –Non-displaced fractures At risk for secondary displacement Urgent ORIF recommended –Displaced fractures Patients native femoral head best AVN related to duration and degree of displacement Irreversible cell death after 6-12 hours Emergent ORIF recommended

13. Treatment Elderly Patients Operative vs. Non-operative –Displaced fractures Unacceptable rates of mortality, morbidity, and poor outcome with non-operative treatment [Koval 1994] –Non-displaced fractures Unpredictable risk of secondary displacement –AVN rate 2X –Standard of care is operative for all femoral neck fractures Non-operative tx may have developing role in select patients with impacted/ non-displaced fractures [Raaymakers 2001]

14. Treatment Pre-operative Considerations Regional vs. General Anesthesia –Mortality / long term outcome No Difference –Regional Lower DVT, PE, pneumonia, resp depression, and transfusion rates –Further investigation required for definitive answer

15. Treatment Pre-operative Considerations Surgical Timing –Surgical delay for medical clearance in relatively healthy patients probably not warranted Increased mortality, complications, length of stay –Surgical delay up to 72 hours for medical stabilization warranted in unhealthy patients

16. ORIF Hemi THR

17. Non-displaced Fractures ORIF standard of care Predictable healing –Nonunion < 5% Minimal complications –AVN < 8% –Infection < 5% Relatively quick procedure –Minimal blood loss Early mobilization –Unrestricted weight bearing with assistive device PRN

18. Open Reduction or Closed Reduction? Open reduction can be considered for any displaced femoral neck fractures that are treated with reduction and internal fixation Open reduction is indicated after an attempt at gentle closed reduction results in a non-anatomic reduction Primary open reduction is preferred in young patients with a displaced femoral neck fracture

19. Approach For Open Reduction Smith-Peterson Anterior approach Best for transcervical and subcapitol fractures Fixation is performed through a second approach

20. Approach For Open Reduction Watson-Jones Anteriolateral exposure Best for basalar neck and IT patterns Allows placement of sliding hip screw through same incision

21. What Reduction Is Acceptable? Ideal reduction is Anatomic –Acceptable: < 15º valgus < 10º AP angulation Any varus is unacceptable Fixation: Multiple screws in parallel –No advantage to > 3 screws –Uniform compression across fracture –In-situ pin impacted fractures * ↑ AVN with disimpaction [Crawford 1960] –Fixation most dependent on bone density

22. Screw Fixation Screw location –Avoid posterior/ superior quadrant »Blood supply »Cut-out –Biomechanical advantage to inferior/ calcar screw [Booth 1998]

23. Sliding Compression Screw Fixation Compression Hip Screws –Sacrifices large amount of bone –May injure blood supply –Biomechanically superior in cadavers –Anti-rotation screw often needed –Increased cost and operative time No clinical advantage over parallel screws * May have role in high energy/ vertical shear fractures

24. Intracapsular Hematoma incidence- 75% have some intracapsular pressure –no difference displaced/nondisplaced sensitive to leg position –extension + internal rotation= bad animal models: intracapsular pressure = perfusion Theoretical benefit with NO clinical proof –but it doesn’t hurt

25. Case Example 42 yo male, MVC

26. Open reduction via Smith-Pete approach, screw fixation placed through separate incision

27. Displaced Fractures Hemiarthroplasty vs. ORIF ORIF is an option in elderly ** Surgical emergency in young patients ** Complications Nonunion 10 -33% AVN 15 – 33% AVN related to displacement Early ORIF no benefit Loss of reduction / fixation failure 16%

28. Displaced Fractures Hemiarthroplasty vs. ORIF Hemi associated with Lower reoperation rate (6-18% vs. 20-36%) Improved functional scores Less pain More cost-effective Slightly increased short term mortality Literature supports hemiarthroplasty for displaced fractures [Lu-yao JBJS 1994] [Iorio CORR 2001]

29. Hemiarthroplasty Unipolar vs. Bipolar Bipolar theoretical advantages Lower dislocation rate Less acetabular wear/ protrusio Less Pain More motion

30. Hemiarthroplasty Unipolar vs. Bipolar Bipolar –Disadvantages Cost Dislocation often requires open reduction Loss of motion interface (effectively unipolar) Polyethylene wear/ osteolysis not yet studied for Bipolars

31. Hemiarthroplasty Unipolar vs. Bipolar –Complications / Mortality / Length of stay No Difference –Hip Scores / Functional Outcomes No significant difference Bipolar slightly better walking speeds, motion, pain –Revision rates Unipolar 20% vs. Bipolar 10% (7 years) –Unipolar more cost-effective Literature supports use of either implant

32. Hemiarthroplasty Cemented vs. Non-cemented Cement (PMMA) –Improved mobility, function, walking aids –Most studies show no difference in morbidity / mortality Sudden Intra-op cardiac death risk slightly increased: –1% cemented hemi for fx vs. 0.015% for elective arthroplasty Non-cemented (Press-fit) –Pain / Loosening higher –Intra-op fracture (theoretical)

33. Hemiarthroplasty Cemented vs. Non-cemented Conclusion: –Cement gives better results Function Mobility Implant Stability Pain Cost-effective –Low risk of sudden cardiac death Use cement with caution

34. Treatment Pre-operative Considerations Surgical Approach –Posterior approach to hip 60% higher short-term mortality vs. anterior –Dislocation rate No significant difference [Lu-Yao JBJS 1994]

35. Total Hip Replacement Dislocation rates: –Hemi 2-3% vs. THR 11% (short term) 2.5% THR recurrent dislocation [Cabanela Orthop 1999] Reoperation: –THR 4% vs. Hemi 6-18% DVT / PE / Mortality no difference Pain / Function / Survivorship / Cost-effectiveness THR better than Hemi [Lu –Yao JBJS 1994] [Iorio CORR 2001]

36. ORIF or Replacement? Prospective, randomized study ORIF vs. cemented bipolar hemi vs. THA ambulatory patients > 60 years of age –37% fixation failure (AVN/nonunion) –similar dislocation rate hemi vs. THA (3%) –ORIF 8X more likely to require revision surgery than hemi and 5X more likely than THA –THA group best functional outcome Keating et al OTA 2002

37. Stress Fractures Patient population: –Females 4–10 times more common Amenorrhea / eating disorders common Femoral BMD average 10% less than control subjects –Hormone deficiency –Recent increase in athletic activity Frequency, intensity, or duration Distance runners most common

38. Stress Fractures Clinical Presentation –Activity / weight bearing related –Anterior groin pain –Limited ROM at extremes –± Antalgic gait –Must evaluate back, knee, contralateral hip

39. Stress Fractures Imaging –Plain Radiographs Negative in up to 66% –Bone Scan Sensitivity 93-100% Specificity 76-95% –MRI 100% sensitivity / specificity Also Differentiates: synovitis, tendon/ muscle injuries, neoplasm, AVN, transient osteoporosis of hip

40. Stress Fractures Classification –Compression sided Callus / fracture at inferior aspect femoral neck –Tension sided Callus / fracture at superior aspect femoral neck –Displaced

41. Stress Fractures Treatment Compression sided Fracture line extends < 50% across neck –“stable” –Tx: Activity / weight bearing modification Fracture line extends >50% across neck –Potentially unstable with risk for displacement –Tx: Emergent ORIF Tension sided Unstable –Tx: Emergent ORIF Displaced –Tx: Emergent ORIF

42. Stress Fractures Complications Tension sided and Compression sided fx’s (>50%) treated non-operatively Varus malunion Displacement –30-60% complication rate AVN 42% Delayed union 9% Nonunion 9%

43. Femoral Neck Nonunion Definition: not healed by one year 0-5% in Non-displaced fractures 9-35% in Displaced fractures Increased incidence with –Posterior comminution –Initial displacement –Inadequate reduction –Non-compressive fixation

44. Femoral Neck Nonunion Clinical presentation –Groin or buttock pain –Activity / weight bearing related –Symptoms more severe / occur earlier than AVN Imaging –Radiographs: lucent zones –CT: lack of healing –Bone Scan: high uptake –MRI: assess femoral head viability

45. Femoral Neck Nonunion Treatment –Elderly patients Arthroplasty –Results typically not as good as primary elective arthroplasty Girdlestone Resection Arthroplasty –Limited indications –deep infection?

46. Femoral Neck Nonunion Young patients (must have viable femoral head) –Varus alignment or limb shortened Valgus-producing osteotomy –Normal alignment Bone graft / muscle-pedicle graft Repeat ORIF

47. Osteonecrosis (AVN) Femoral Neck Fractures 5-8% Non-displaced fractures 20-45% Displaced fractures Increased incidence with –INADEQUATE REDUCTION –Delayed reduction –Initial displacement –associated hip dislocation –?Sliding hip screw / plate devices

48. Osteonecrosis (AVN) Femoral Neck Fractures Clinical presentation –Groin / buttock / proximal thigh pain –May not limit function –Onset usually later than nonunion Imaging –Plain radiographs: segmental collapse / arthritis –Bone Scan: “cold” spots –MRI: diagnostic

49. Osteonecrosis (AVN) Femoral Neck Fractures Treatment –Elderly patients »Only 30-37% patients require reoperation Arthroplasty –Results not as good as primary elective arthroplasty Girdlestone Resection Arthroplasty –Limited indications

50. Osteonecrosis (AVN) Femoral Neck Fractures Treatment –Young Patients »NO good option exists Proximal Osteotomy –Less than 50% head collapse Arthroplasty –Significant early failure Arthrodesis –Significant functional limitations ** Prevention is the Key **

51. Femoral Neck Fractures Complications Failure of Fixation –Inadequate / unstable reduction –Poor bone quality –Poor choice of implant Treatment –Elderly: Arthroplasty –Young: Repeat ORIF Valgus-producing osteotomy Arthroplasty

52. Femoral Neck Fractures Complications Post-traumatic arthrosis Joint penetration with hardware AVN related Blood Transfusions –THR > Hemi > ORIF –Increased rate of post-op infection DVT / PE –Multiple prophylactic regimens exist –Low dose subcutaneous heparin not effective

53. Femoral Neck Fractures Complications One-year mortality 14-50% Increased risk: –Medical comorbidities –Surgical delay > 3 days –Institutionalized / demented patient –Arthroplasty (short term / 3 months) –Posterior approach to hip