Fracture Of Femoral Neck In Adults

1. Fracture Of Femoral
Neck In Adults
By
Ihab El-Desouky (M.D.)
Associate Prof. Pelvis and Reconstruction unit.
Kasr Al-Ainy School of Medicine
November 2018

2. Femoral neck fracture in Adults
•Aim
1. Background
2. Anatomy
3. Epidemiology
4. Patho-anatomy + Classifications
5. Mechanism of injury
6. Clinical presentation/Radiological
investigation
7. Aims of treatment
8. Management
9. Complications

3. Femoral neck fracture in Adults
•Background:
• Predominantly in the elderly, low-energy
falls, with osteoporosis
• In young patients (below 50 years)
a high-energy mechanism, associated
injuries
• Intra-capsular and may compromise the
tenuous blood supply to the femoral head
• Basi-cervical fractures are extracapsular

4. Femoral neck fracture in Adults
•Anatomy
• The upper femoral epiphysis closes by
age16-18 years.
• Neck-shaft angle:
130 ±7 degrees
• Femoral Anteversion:
10 ±7degrees

5. Femoral neck fracture in Adults
•Anatomy:
• Three ligaments attach :
• 1. Iliofemoral: Y –ligament of
Bigelow(anterior)
• 2. Pubofemoral: Anterior
• 3. Ischiofemoral:Posterior

6. Femoral neck fracture in Adults
•Anatomy
• Calcar Femorale
Posteromedial dense plate of bone
• Trabecular pattern

7. Femoral neck fracture in Adults
• Anatomy: Blood supply
1-Capsular vessels:medial circumflex (major)
+lateral cir femoral artery----
Extracapsular ring (neck base) -›
Ascending cervical arteries ---- penetrate cap
-› 4 groups
Subsynovial intraarticular ring (head base)
lateral group (lateral epiphyseal vs) Post +Sup
is largest contributor to head.
2- Artery of ligamentum teres -› of
Obtutaror artery
3-Medullary vessels/ endosteal supply

8. Femoral neck fracture in Adults
•Anatomy
• Greater fracture displacement = greater risk of
retinacular vessel disruption
• Tamponade effect of blood after # in intact
capsule
• Theoretical risk of AVN with increased pressure

9. Femoral neck fracture in Adults
•Epidemiology:
• 250,000 hip fractures occur in the United States each
year (50% involve the femoral neck)
• Elderly : (97%)
• Female to male ratio:3 :1
• Patients with a femoral neck fracture are at risk for a
second hip fracture and falls :by 5 -7 folds within 3 years
• Young (3%)

10. Femoral neck fracture in Adults
• Epidemiology: Bimodal distribution.
• Elderly
• incidence doubles each decade beyond age 50
• Earlier than intertrochanteric #
• higher in females, caucasians ,smokers, lower BMI (fat),
excessive caffeine & alcoholics.
• Predisposing factors
1-Loss of bone strength
2-Loss of local shock absorbers (fat)
3-Reduction in protective responses (muscle weakness)
4-Increased risk of falls (alcholics,visual acuity)
5-Previous fractures: 5-7 folds
• Young
• high energy trauma

11. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
• The hip capsule inserts into the intertrochanteric
line (anteriorly) and the intertrochanteric crest
(posteriorly).
• Intracapsular fractures ----disruption of the
capsular retinacular vessels---
blood supply to the femoral head at risk

12. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
• Trauma: anterior capsule holds the femoral
head fixed-----hip rotates externally+
the posterior cortex of the neck impinges on the
lip of the acetabulum.
• Anterior cortex fails in tension
+ posterior cortex is compressed ---
posterior comminution—External
Rotation
• Distal fragment – ext rotation,
Adducted and proximal migration (muscle pull)

13. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
• Classifications:
1-Anatomical Location
2-Garden
3-Pauwels
4- AO/OTA
1-Anatomical Location:
Sub-capital
Trans-cervical
Basi-cervical

14. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
2-Garden ‘s Classification (1961)
Degree of displacement
Relates to risk of vascular disruption
Most commonly applied to geriatric/ insuffiency fractures
Stage I: Stage II:
incomplete fracture line complete fracture line;
(valgus impacted) nondisplaced

15. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
Stage III: Stage IV:
complete fracture line complete fracture line;
Partially displaced totally displaced (continuous)
• But:Poor inter-observer reliability
• Modified to:
• Non-displaced: stages I &II
• Displaced: stages III &IV (retinacular vs disruption)

16. Femoral neck fracture in Adults
• Patho-anatomy and classifications:
3-Pauwels’ Classification (1935)
-Fracture line angle from horizontal, three types
-Relates to biomechanical stability---more vertical
fracture has more shear force
-More commonly applied to younger patients or higher
energy fractures

17. Femoral neck fracture in Adults
4-AO/OTA
FEMUR NECK IS 31-B
• B1 nondisplaced (minimally displaced)
subcapital fracture
• B2 transcervical
• B3 all displaced
Subcapital fractures

18. Femoral neck fracture in Adults
• Mechanism of injury
• Low Energy: elderly
-Direct: Falling directly onto the hip
-Indirect: Twisting mechanism (tripping over a
loose carpet)
• High Energy: young.
Motor car accident, fall from a height
• Cyclical Loading :Stress fracture

19. Clinical presentation/Radiological investigation
1-Clinical Presentation:
History of a traumatic event (except in
stress fractures)
• Young patients with high-energy ---associated injuries
including head.
• Missed fracture can be disastrous.
Clinical examination
• Shortening
• External rotation
• Inability to SLR
• Groin tenderness
Femoral neck fracture in Adults

20. Femoral neck fracture in Adults
• Radiological investigation:
1-Plain radiograph (Antero-posterior and Lateral)
2-MRI
3-CT
4-Bone Scan
1-Plain radiography:
• Extent Of fracture : Complete/Incomplete
• Pauwels’ angle
• Break of Shenton Line
• Proximal migration of the greater trochan.
• Prominent lesser trochanter (ex rot)
• Posterior Wall Comminution (lat. View)

21. Femoral neck fracture in Adults
1-Plain radiography: Views:
• X-ray A/P View Pelvis
•Cross-table Lateral View Of The Hip
• Full femur A/P And Lateral (# femur in 5%)
• Traction and internal rotation A/P view of Hip
(incomplete or un-displaced #)

22. Femoral neck fracture in Adults
2-MRI
• Occult femoral neck fracture.
• elderly patient who is persistently unable to
weight bear.
• 100% sensitive and specific
• May reduce cost by
shortening time to diagnosis
• Femoral head viability in FU

23. Femoral neck fracture in Adults
3-CT
- Comminution preoperatively
-Abnormalities of bone in pathological #
-Check for union postoperatively
4-Bone Scan
Increased uptake :
80% of cases after 24 hr
; 95% at 7 days

24. Femoral neck fracture in Adults
7. Aims of treatment:
For elderly patients : >65 ys.
• Mobilize
• Weight bearing as tolerated
• Minimize period of bedrest
• Minimize surgical morbidity
• Safest operation
• Decrease chance of reoperation

25. Femoral neck fracture in Adults
7. Aims of treatment:
For young patients : <55- 65 ys
• Spare femoral HEAD
• Avoid varus deformity
• Improves union rate
• Optimal functional outcome (offset)
• Minimize vascular injury
• Avoid AVN

26. Femoral neck fracture in Adults
• Treatment Options
• Non-operative
• Limited role
• Usually high operative risk patient
• Valgus impacted fracture
• Elderly need to be WB as tolerated
• Mobilize early
• Operative:
• Reduction and fixation
• Open or percutaneous
• Arthroplasty
• Hemi or total

27. Femoral neck fracture in Adults
• Operative treatment: Decision Making Variables:
1-Patient Factors
• Young (active)
– High energy
injuries
• Often multi-
trauma
– Often High
Pauwels Angle
(shear)
• Elderly
– Lower energy
injury (falls)
– Comorbidities
– Pre-existing hip
disease

28. Femoral neck fracture in Adults
2-Fracture Characteristics
• Displacement: (I &II) Vs (III & IV)
• Stability
– Pauwels’ angle
– Comminution, especially posteromedial

29. Femoral neck fracture in Adults
•Pre-operative Considerations
• Traction not beneficial
– No effect on fracture reduction
– No difference in analgesic use
– Pressure sore/ skin problems (limited Pt rolling)
– Increased cost
– Traction position decreases capsular volume
• Capsule volume greatest in flexion/external rotation
• Potential hazardous effect on blood flow by increasing
intra-capsular pressure (tamponade)

30. Femoral neck fracture in Adults
•Pre-operative Considerations:
Timing of surgery in Young
• Surgical Urgency

31. Femoral neck fracture in Adults
•Pre-operative Considerations:
Timing of surgery in Young
-Jain et al. (2002) : fixation within 12 h Vs delayed fixation
(>12 h) ----AVN 16% in the delayed group & 0% in the early
group .
-Barnes et al.(1976) timing of surgery did not affect the
rates of nonunion and AVN within the first week post-
injury
-Experimental studies (Keating ;2009) ---- osteocytes
viability continue up to 3 weeks post-fractures
-Fixation is done on day of trauma, delayed cases up to 2
weeks --- fixation with accepted imperfect reduction

32. Femoral neck fracture in Adults
•Pre-operative Considerations:
Timing of surgery in Elderly >65ys
• Surgical urgency in relatively healthy patients
(decreased mortality, complications, length of
stay)
• Surgical delay up to 72 hours for medical
stabilization warranted in unhealthy patients
• 2.25 increase in MORTALITY if > 4 day delay
• related to increased severity of medical
problems (chest, cardiac, Renal)

33. Femoral neck fracture in Adults
Treatment Options:
Young patient
• Open reduction
– Improved accuracy
– Decompresses capsule
(capsulotomy)
• May have greater risk
of infection
• Closed reduction
– Less surgical morbidity

34. • Higher rate of deep infection in open reduction group
• 0.5% versus 4%
• No difference in AVN
• 17% in both groups
• No difference in nonunion
• 12% in closed group versus 15% in open group (p = 0.25)
MUST achieve an appropriate reduction regardless of
either method
Closed versus Open Reduction INJURY 2015

35. Closed Reduction Techniques
• Leadbetter Technique
• Flexion, slight adduction
• Apply traction, internally
rotate to 45 degrees,
followed by full
extension, slight
abduction
• Whitman technique
traction to the abducted,
extended, externally
rotated hip
followed by internal
rotation.

36. Open Reduction: Approach
• Watson-Jones
• anterolateral
• Between TFL and
gluteus medius
• Best for basicervical

37. • Fracture table Radiolucent under pelvis
• Use Schanz pins, weber clamps for reduction
Open Reduction Technique

38. Femoral neck fracture in Adults
Assessment of reduction:
-Reduction should be judged on A/P and lateral
views
-Junction of the convex femoral head and neck --
---S-shaped curve in all planes
-Valgus reduction is preferable to a varus
reduction (more stable less risk of fixation
failure)

39. Femoral neck fracture in Adults
• Assessment of Reduction
Garden Alignment Index bony trabecular alignment.
A/P view Angle between central axis of medial trabecular
system in the head + medial cortex ---160°.
-Lateral view the central trabecular axis is in
line + femoral head at 180°
Angle between 160-180° in either view good
reduction

40. Fixation Methods
• 3 cannulated Screws
• 4 cannulated Screws
• Dynamic hip screw
(with anti-rotation S)
• Blade plate

41. Femoral neck fracture in Adults
• 3 cannulated screws fixation:
• 3 partially threaded screws in inverted triangle
configuration (apex-distal)

42. Fixation Concepts
• Reduction makes it
stable
• Avoid ANY varus
• Avoid inferior offset
• Malreduction likely
to fail

43. Fixation Concepts
• Screw position Spread
• Inferior within 3 mm of cortex
• Posterior within 3 mm of cortex
• Need one screw resting on calcar
• Threads should end at least 5mm
from subchondral bone
• Multiple views to check
appropriate depth
• Avoid posterior/superior
• to avoid iatrogenic vascular damage (lat
epiphyseal V.)
• Should not start below level of
lesser trochanter
• Avoid many perforations
• Avoid stress riser---subtrochanteric #

44. Fixation Concepts
Good Bad
Posterior Anterior
Lateral
Epiphyseal
Artery
- Good spread
- Hugging Calcar and
posterior cortex
- Posterior and inferior
screws are most important
- Clustered together
- Nothing on calcar

45. Fixation Concepts
• Apex distal screws less prone to subtrochanteric
fractures then apex proximal
• Vertical fractures (Pauwels angle > 50)
More shear forces ---
prone to failure (use DHS)

46. Fixation Concepts
• 4 cannulated screws
In significant comminution
• Sliding hip screw
• May help with comminution
• Basicervical
• Vertical fractures
• Accessory screw for rotation
• Revision if screws failed
• No mechanical Advantage
over screws.

47. Treatment Options:
Geriatric Patients
• Fixation
• Lower surgical risk
• Higher risk for
reoperation
• Replacement
• Higher surgical risk
• Fewer reoperations
• Better function
• Use
– Stable (valgus
impacted) fractures
– Minimally displaced
fractures
• Use
– Displaced fractures
– Unstable fractures
– Poor bone quality

48. Treatment Options:
Geriatric Patients

49. Treatment Options:
Geriatric Patients

50. Arthroplasty Issues:
Hemiarthroplasty versus THA
• Hemi
• More revisions
• 6-18%
• Smaller operation
• Less blood loss
• More stable (large head
• Total Hip
• Fewer revisions
• 4%
• Better functional outcome
• More dislocations
( use Dual Mobility)

51. Hemiarthroplasty Issues:
Unipolar vs. Bipolar Hemiarthroplasty
• Unipolar
• Lower cost
• Simpler
• Bipolar
• Theoretical less wear
• More modular
• More expensive
• Can dissociate
• NO PROVEN
ADVANTAGE

52. Arthroplasty Issues:
Cement Or Cementless
• Cement (PMMA)
• Improved mobility,
function, walking aids
• Most studies show no
difference in morbidity /
mortality
• Sudden Intra-op cardiac
arrest
• Non-cemented (Press-fit)
• Pain / Loosening higher
• Intra-op or periop fracture
risk higher (in men > 80
years)

53. Arthroplasty Issues:
Surgical Approach
• Posterior
• 60% higher short-term
mortality
• Higher dislocation rate
• Anterior/Anterolateral
• Fewer dislocations

54. GERIATRIC Summary
• MRI to rule out occult fracture in older patients
unable to weight bear
• CRPP for valgus impacted or nondisplaced fractures
• Arthroplasty if displaced
• Hemi in debilitated
• Consider THA for active older patients and
associated arthritis.
• Cemented stems
• Anterior and antero-laterl approach

55. Special Issue:
Stress Fractures
• Females 4–10 times more common
• Amenorrhea / eating disorders (Coeliac disease common)
• Hormone deficiency
• Recent increase in athletic activity
• Clinical Presentation
• Activity / weight bearing related pain
• Anterior groin pain
• Limited ROM at extremes
• ± Antalgic gait
• Must evaluate back, knee, contralateral hip

56. 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

57. Stress Fractures
• Classification
• Compression sided
• Callus / fracture at inferior
aspect femoral neck
• Tension sided
• Callus / fracture at superior
aspect femoral neck
• Displaced or non

58. Stress Fractures:
Treatment
• Compression sided
• Fracture < 50% across neck
• “stable”
• TTT: Activity / weight bearing modification
• Fracture >50% across neck
• Potentially unstable with risk for displacement
• TTT: fixation
• Tension sided
• - Nondisplaced------Unstable
• TTT: fixation (Protect weight bearing till fixation ASAP)
• - Displaced
• TTT: fixation
• Fix within 24 hours

59. COMPLICATIONS
1-Non-union
2-Osteonecrosis (AVN)
3-Failure of fixation
4-Fracture distal for fixation (sub trochanteric)
5-Post-traumatic arthrosis.
6-Blood transfusion
7-DVT and PE
8-Mortality.

60. COMPLICATIONS
1-Non-union
• 0-5% in Non-displaced fractures
• 9-35% in Displaced fractures
• Increased incidence with
– Posterior comminution
– Initial displacement -Imperfect reduction
– Non-compressive fixation
• Clinical presentation
– Groin or buttock pain
– Activity / weight bearing related
– Symptoms : more severe / occur earlier than AVN

61. Non-union
• Imaging
• Radiographs: lucent zones
• CT: lack of healing
• Bone Scan: high uptake
• MRI:
assess femoral head viability

62. Non-union
Treatment:
• Young patients
– Valgus intertrochanteric
osteotomy (Pauwels)
– Creates compressive forces

63. Non-union
•Elderly patients
•Arthroplasty
• Results typically not as good as
primary elective arthroplasty
•Girdlestone Resection Arthroplasty
• Limited indications (if infection)

64. Special Problems:
Osteonecrosis (AVN)
• Up to 10% of nondisplaced and up to 30% of
displaced fractures
• Increased incidence with
• Inadequate Reduction
• Delayed reduction ??
• Initial displacement
• associated hip dislocation

65. Osteonecrosis (AVN)
• 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

66. Osteonecrosis (AVN)
• Treatment
• Elderly patients
• Only 30-37% patients require reoperation
• Arthroplasty
• Results not as good as primary elective arthroplasty
• Girdlestone Resection Arthroplasty
• Limited indications
Young Patients
-Proximal Femoral Osteotomy
If Less than 50% head collapse
-Arthroplasty
-Arthrodesis
Significant functional limitations
** Prevention is the Key **

67. COMPLICATIONS
• Failure of Fixation
• Inadequate / unstable reduction
• Poor bone quality
• Poor choice of implant (Vertical #)
• Treatment
• Elderly: Arthroplasty
• Young: -Repeat ORIF by DHS
augmented by tri-calcium phosphate
or bone cement
-Valgus-producing osteotomy
-Arthroplasty

68. COMPLICATIONS
• Fracture Distal to Fixation (Subtrochat)
– 20% if screws at or below Lesser Trochanter
– Poor bone quality esp. with anterior start site
– Poor angle of screw fixation
– Multiple passes of drill or guide pin
Treatment
– Elderly & Young:
– Fixation of subtrochanteric with IMN

69. Complications
• Post-traumatic arthrosis
• Joint penetration with hardware
• AVN related
• Blood Transfusions
• THR > Hemi > ORIF
• DVT / PE
• Multiple prophylactic regimens exist

70. Complications
Mortality
• One-year mortality 14-50%
• Increased risk:
• Medical comorbidities: more falls
• Surgical delay > 3 days
• Dementia patient

72. Thank you