O&T SC045: My Granny Broke Her Hip: Management Of Osteoporotic Fractures

Question 1

Anatomy of Hip

Answer 1

Hip: Misnomer —> Correct name: Proximal femur

Anatomy of femur:
1. Head
2. Neck
3. Trochanter
4. Subtrochanteric region

Blood supply to femoral head:
1. Retinaculum vessels (majority)
- from **Medial (> Lateral) femoral circumflex artery (MFCA)
—> extra-capsular arterial ring (form an arterial anastomosis at base of femoral neck)
—> ascending cervical capsular branches (retinacular arteries) (within hip capsule)
—> **epiphyseal arteries that penetrate femoral head

2. Ligamentum teres artery
   - from obturator artery / medial femoral circumflex artery (MFCA)
   - not effective in adults
3. Intramedullary vessel (Nutrient artery)
   - small contribution

Question 2

Clinical features of Hip fracture

Answer 2

1. Shortened leg
2. Externally rotated

Question 3

Risk factors for Hip fracture

Answer 3

1. Increased risk of falls
   - Concurrent medical illness
   - Drugs - tranquillisers, alcohol
   - Dementia / Sarcopenia / Visual impairment
2. Reduction in protective responses
3. Loss of local shock absorbers
4. Loss of bone strength
   - Drugs - corticosteroids, anticonvulsants, thyroxine, alcohol
   - Smoking
   - Vit D deficiency
   - Ca deficiency
   - Physical inactivity

Question 4

Investigations in Hip pain with normal X-ray

Answer 4

1. Repeat X-ray (not sensitive but specific)
2. CT (not sensitive but specific)
3. MRI (Most sensitive + specific)
4. Bone Scan (sensitive but not specific) (Tc-99m taken up by osteoblast)

Question 5

***Classification of Hip fracture

Answer 5

This classification have different management!!!

1. Extracapsular (Stable vs Unstable (Calcar comminution, Lateral wall fracture))
   - **Trochanteric (TOF)
   —> Intertrochanteric (line of fracture between 2 trochanter)
   —> Peritrochanteric (line of fracture going through 2 trochanter)
   - **Subtrochanteric

Effect:
- Only nutrient artery is disrupted, capsule remain intact —> blood supply from MFCA intact

2. Intracapsular (**Garden’s classification: Displaced vs Undisplaced)
   - **Neck of femur (NOF)
   —> Subcapital
   —> Transcervical
   —> Basicervical

Effect:
- Blood supply to femoral head is jeopardised
- Accumulation of haematoma within capsule —> build up pressure —> reduce blood supply to femoral head
—> End result: ***Avascular necrosis of femoral head

Question 6

Considerations in Fracture NOF

Answer 6

1. ***Age
2. ***Displacement
3. Save the femoral head in young age / undisplaced
4. Time of presentation: AVN ( 6hr)
5. Patient’s general health
6. Risk factors for internal fixation failure
   - Old age
   - Osteoporosis
   - Too comminuted
   - Sepsis
   - Vertical fracture pattern (∵ larger shear stress)
   - Delayed presentation

Question 7

***Surgical treatment of Hip fracture + Garden’s classification

Answer 7

Extracapsular:
- Stable —> **Reduction + Fixation: Dynamic hip screw / Proximal femoral nail
- Unstable —> **Reduction + Fixation: Proximal femoral nail (Dynamic hip screw not sufficient)

Intracapsular:
Garden’s classification:
- Undisplaced:
Class 1: **valgus impacted, undisplaced fracture
Class 2: **complete but undisplaced fracture
—> Avascular necrosis 5-10%, Non-union 5-10%
—> ***Reduction + Fixation: Cannulated screws / Femoral neck system (FNS)
(Reduction may not even be needed (i.e. In-situ))

• Displaced:
  Class 3: complete fracture, **partial displacement indicated by **change in angle of trabeculae
  Class 4: complete fracture, **complete displacement leading to **parallel orientation of trabeculae (no more soft tissue connection between head and trochanter —> head will align with acetabulum)
  —> Avascular necrosis 10-20%, Non-union 20-30%
  —> **Young (<65): Urgent Reduction (open / close) + Fixation: Femoral neck system (FNS)
  —> **Geriatric (>65): Replacement: Hemiarthroplasty / Total hip replacement (NOT save the femoral head ∵ destined to fail)

Question 8

Stable vs Unstable extracapsular fracture

Answer 8

Stable:
1. Oblique pattern
2. Minimal comminution
—> Repair with DHS

Unstable:
1. Calcar comminution —> after reduction —> very little support on posteromedial side —> proximal femur prone to displacement + collapse
2. Lateral wall fracture —> cannot prevent proximal femur from sliding
3. Reverse obliquity

Calcar:
Posteromedial cortex of trochanter
—> Thick bone
—> Important for support of proximal femur

Question 9

Dynamic hip screw, Proximal femoral nail

Answer 9

Dynamic hip screw (aka Sliding hip screw)
- an **extramedullary device
- **dynamic: more than 1 component —> provide controlled subsidence
- Cheap ~$1000
- Technically easier
- Less risk of iatrogenic fracture
- Requires more simple fracture patterns

Proximal femoral nail (aka Cephalomedullary device)
- an ***intramedullary device
- also dynamic that can slide —> provide controlled subsidence
- much stronger implant than DHS
- Expensive ~$7000
- Technically difficult
- Intramedullary fixation is mechanically stronger
- Less change for excessive collapse

Question 10

Complications of Hip fracture (SpC Revision)

Answer 10

1. Non-union
2. Avascular necrosis
3. Secondary OA
4. Implant related complication (e.g. failure, infection)
5. Immobility —> Contracture, Pneumonia, Bed sores, UTI, DVT

Question 11

Fragility fracture

Answer 11

• A fracture caused by injury that would be insufficient to fracture a normal bone, that occurs as a result of a ***minimal trauma e.g. fall from standing height or less, or no identifiable trauma
  —> osteoporosis until proven otherwise

Common sites:
1. Distal radius (Wrist)
2. Olecranon
3. Proximal humerus
4. Vertebral collapse
5. Proximal femur
6. Distal femur
7. Pelvic insufficiency fracture

Question 12

Osteoporosis

Answer 12

Disease characterised by loss of bone mass, reduction in bone quality by microarchitectural deterioration of bone tissue, reduced ability of bone to withstand loading
—> Consequently, susceptible to fragility fracture

Question 13

Epidemiology of Fragility fracture

Answer 13

• 1 in 3 women / 1 in 5 men >50 yo will sustain an osteoporosis-related fracture
• 2 in 10 will die in first year
• 1 in 5 will have a history of previous fracture (frequent relapse) (Progression: Wrist fracture —> Vertebral fracture —> Hip fracture)
• 4 in 10 will not return to house / independent living
• 8 in 10 cannot carry out independent ADL
• 2 in 10 will be re-admitted within 60 days (frequent hospitalisation)
• 8 in 10 will not be investigated / treated for osteoporosis
• Risk higher in CA breast / uterus / ovarian / prostate

Incidence in HK:
- 14000 fragility fracture in 2014 (1 fragility fracture every 37 mins)
- Personal suffering
- Economic cost

Question 14

***Principles of fracture treatment

Answer 14

1. Reduction if necessary
2. Immobilisation if necessary
3. Rehabilitation always

Principles of ***Fragility fracture treatment:
- Goes beyond fracture fixation
4. Keep patient alive —> Medical optimisation (Optimise physiology, may need geriatric consultation)
5. Pain control
6. Fix fracture —> Surgical challenges
7. Keep patient mobile —> Multidisciplinary rehabilitation
8. Keep patient from coming back —> Osteoporosis management + Secondary prevention

Question 15

Typical patient presentation in Fragility fracture

Answer 15

1. Abnormal bones (very porotic)
2. Comorbidities (ASA (American Society of Anesthesiology) class)
   - cause / complicate fall
3. Polypharmacy
4. Impaired physiological reserve (e.g. poor cardiopulmonary function)
5. Impaired cognitive function
6. Unable to unload injured extremity due to general weakness / poor balance —> must bear full weight
7. Marginally independent ADL +/- live alone

Question 16

Timing of surgery

Answer 16

Balance: Time spent for medical optimisation (risk of morbidity / mortality of delayed surgery) vs Benefit of prompt surgery (risk of inadequate optimisation —> medical complications)

Principle:
- **As early as possible (<48 hours)
- **Quick optimisation —> Early surgery
- Patient should be optimised if there are measures to lower risk of surgery
- But if risk of surgery cannot be altered —> surgery should be performed without further delay

Pre-op quick workup:
1. CBC
2. LRFT
3. ECG
4. CXR
5. Medication: Anticoagulant, Antiplatelet (may need stop for 1-2 days)

Conditions that need optimisation:
1. Anaemia
2. Anticoagulation
3. Volume depletion
4. Electrolyte imbalance
5. Uncontrolled DM
6. Uncontrolled heart failure
7. Correctable cardiac arrhythmia + ischaemia
8. Acute chest infection
9. Exacerbation of chronic chest condition (e.g. COPD)

Question 17

Surgical challenges in fixing fractures

Answer 17

1. Osteoporotic bone
   - Impaired ability to hold screw in place —> pullout of screw
   - Bone void (bone defect) after disimpaction / close reduction —> alignment difficult to be maintained with cast
   - Iatrogenic comminution
2. Fragile soft tissue
   - Surgical trauma
3. Existing metal implant
   - Limited fixation options

Question 18

1. Osteoporotic bone: Solutions

Answer 18

1. Improve fixation implants for osteoporotic bone
2. Alternative fixation / replacement implants
3. Surgical technique advancement
4. Bone void management

Screw design:
- Locking screw (screw and plate locked together to become one angle-stable construct —> stronger)
- Blade
- Cement augmentation

Plate design:
- Fixed angle plate / Locking plate
- Long plate (spanning whole long bone)

Intramedullary device:
- Load sharing implant
—> Mechanically more advantagious than Extramedullary device —> less affected by osteoporosis than plate and screws

Arthroplasty (Joint replacement):
- No fracture fixation —> Avoid complication from fixation failure
- Allow early mobilisation

Surgical technique advancement:
- Use of soft tissue attachment (suture soft tissue to screw) to improve fixation

Question 19

2. Fragile soft tissue: Solution

Answer 19

1. Minimally invasive surgery
2. Gentle retraction + manipulation
3. Indirect reduction
4. Intramedullary device (rather than long plates: longer wound)

Question 20

Summary: Surgical intervention for elderly

Answer 20

• As early as possible
• Aim: Pain free, Stable, Mobile
• “Single-shot” surgery
• As short as possible, minimise blood loss
• Minimally invasive / Biologically friendly technique
• Optimal implant for osteoporotic bone
• Must allow immediate full weight-bearing —> by Rigid fixation
• ***Early mobilisation + Restoration of function MORE important than perfect anatomy —> in elderly some degree of deviation / minor loss of reduction is accepted (against traditional principles of immobilisation in younger adults)

Paradigm shift:
Past:
- Conservative
- 3rd class priority
- Low precision surgery

Now:
- Prompt attention + priority
- Elderly specifically benefits from surgical stabilisation of fracture for early mobilisation
- Pain relief, prevent functional decline, maintain independence, prevent complication of immobilisation

Question 21

Multidisciplinary rehabilitation

Answer 21

1. Return patient to pre-fracture capabilities
2. Prevent recurrent falls + fracture
3. Geriatric Fracture Hip Pathway (in HA —> more standardised treatment)
4. Multidisciplinary: cognition, depression, mobility, fall risk, nutrition, continence, vision
5. Sustainable rehabilitation services in the community post-discharge

Address 2 tissues:
1. Bone fragility
2. Tendency to fall

Question 22

Secondary prevention

Answer 22

Determined attempt to prevent another one after 1 fragility fracture
1. Identify (capture the fracture)
2. Investigate
- Blood tests
- DEXA scan
- FRAX score (calculate risk of future fracture)
3. Initiate treatment
4. Discharge with bone protection medication
- Ca, Vit D, Bisphosphonate
—> pharmacological intervention can substantially attenuate risk of second fracture, improve QoL, reduce mortality

Fracture Liaison Service:
- A nurse coordinator-based service
- For secondary fracture prevention + sustained rehabilitation in the community
- By systemically identifying all eligible patients at the time of acute fracture
- Providing them easy access to osteopororis + multidisciplinary care
- Orthopaedic ward / Fracture clinic / General orthopaedic clinic —> Fracture Liaison Service —>
1. Osteoporosis assessment + treatment
2. Fall risk assessment
3. Exercise programme
4. Education programme

Members:
1. Coordinator (leader)
2. Patient
3. Orthopaedic team
4. Family physician
5. Fall service
6. Osteoporosis service

Question 23

Fall prevention

Answer 23

1. Review +/- Adjust patient’s medication
   - Anti-HT
   - Psychoactive drugs
   - Anticonvulsants
2. Evaluation of gait
3. Evaluation of vision
4. Evaluation of cognitive function
5. Home assessment (rails, lighting, loose rugs / carpets, pets)
6. Proper footwear

Question 24

Standards for Fragility hip fracture care

Answer 24

1. Admission to orthopaedic ward in 4 hours
2. Surgery in 48 hours
3. Prevent pressure ulcer
4. Pre-op assessment by ortho-geriatrician
5. Optimal surgical + non-surgical management
6. Short stay in acute hospital
7. Speedy discharge home
8. Multidisciplinary sustainable rehabilitation service in community
9. Discharged on bone protection medication
10. Receive a fall assessment
11. Prevention of secondary fracture

Question 25

Summary

Answer 25

• Fragility fracture is a serious challenge: Medical, Surgical, Logistic complexity
• Treatment of fragility fracture goes beyond fracture fixation
• Multidisciplinary work is crucial
• Surgical intervention tailored to elderly physiology + anatomy
• Absolute necessity to deliver secondary prevention to prevent further fractures + save lives

Question 26

SpC O/T Seminar: Osteoporotic Related Fractures
Other bones prone to AVN

Answer 26

Scaphoid, Talus (∵ retrograde bloodflow)

Question 27

Osteoporosis

Answer 27

Definition:
- Systemic skeletal disorder
- Characterised by low **bone mass
- Micro-architectural deterioration of **bone tissue
- Leading to bone fragility

End result:
- Consequent increase in fracture risk

Treatment:
Non-pharmacological
1. Exercise
2. Sunlight
3. Nutritional (Vitamin D + Calcium)
4. Risk factor modification

Pharmacological
1. Bisphosphonates (Alendronate)
2. Teriparatide (PTH analogue)
3. Denosumab (RANKL inhibitor)
4. Strontium ranelate
5. SERMs (Raloxifene)
6. HRT

Question 28

Upper vs Lower limb fracture

Answer 28

Lower limb
- For locomotion
- **Difficulty pain control with weight bearing
- **Significant morbidity with displacement / delayed union

Upper limb
- For self care function
- Better managed by ***immobilisation
- Usually recovers with time and rehabilitative training

Question 29

Atypical femoral fractures related to Bisphosphonates

Answer 29

1. Reduced bone turnover
2. Microfractures accumulation
3. Stress fracture
4. Eventual displacement with minimal trauma
5. **“Beak” sign on X-ray and **“Dreaded black line”
   - osteoclast cannot remove bone but osteoblast keep forming new bone
6. Relation with ***bisphosphonate use >3 years
7. Benefit of bisphosphonates still > risks

Question 30

Distal radial fractures

Answer 30

Evaluation:
- Patient’s functional demand
- ***Neurological exam (median nerve)
- Fluoroscopy
- CT assessment

Classification:
A: Extraarticular (within width of joint) —> **Colles’ / Smith Fracture (Dorsal angulation, Dorsal displacement, Radial angulation, Radial displacement, Radial shortening)
B: “Partial” articular —> **Barton fracture
C: “Complete” articular

Problem:
- Changes in wrist mechanics may lead to arthrosis especially with intraarticular steps

Problems with acute displacement:
- Pain
- Unstable
- Nerve impingement (Median nerve)
- Loss of reduction
- Skin impingement
- **Tendon impingement (*EPL)

(From SpC O/T 10 common ortho problems)
P/E:
1. Neurology
- **Carpal tunnel syndrome
- **EPL (due to decreased in nutrient supply after injury)

Investigations:
1. X-ray
Normal alignment:
- Coronal plane: **Radial Angle (RA) (Ulnar slant) 22o
- Sagittal plane: **Palmar Tilt (PT) (Volar inclination) 11o

Look for:
- **Malalignment (Dorsal angulation, Dorsal displacement, Radial angulation, Radial displacement)
- **Radial shortening
- ***Intra-articular fracture: step-off and gap (acceptable < 2mm)

Factors for treatment:
1. Fracture characteristics
2. Age

Treatment:
1. ***CR + POP
- if alignment not acceptable + immobilisation
—> Intra-articular fracture: long arm POP x3 weeks then short arm x3 weeks
—> Old patient: slab x 4-6 weeks
—> May need change of POP if decrease swelling
—> F/U X-ray

2. ***OR + IF
   - poor alignment / sign of Intra-articular step/gap

Question 31

Late complication of Distal radial fracture (SpC Revision)

Answer 31

1. Median nerve palsy
   - related to malunion
2. EPL rupture
   - fracture abrasion / blood supply disruption
   - usually 4-8 weeks after fracture (delayed rupture)
   - treatment: Tendon transfer
3. Compartment syndrome / Pressure ulcers
   - cast too tight
4. Stiffness
   - immobilise for too long / lack of rehabilitation
   - cast not kept >6 weeks

Question 32

Treatment of Distal radial fractures

Answer 32

Treatment:
1. CR + Immobilisation
—> Anaesthesia (Haematoma block with 1% Lidocaine)
—> Longitudinal traction
—> Disimpact fracture by exaggerate angulation
—> 3 point fixation with cast

Indications: (Most do NOT need an operation)
- Non-displaced fractures
- Well reduced stable fractures
- Very low demand patients
- Geriatric

Caution:
- Bad cast: too tight (compartment syndrome) / too loose
- Loss of reduction

Post-treatment:
- Cast immobilization
- Bone Healing after 4 weeks
- Physiotherapy / Occupational therapy
- ROM exercise and strengthening

2. Surgery
   - Evaluate patient’s functional demand
   - Do a neurological exam (median nerve)
   - Fluoroscopy
   - CT assessment

Indications:
- High grade open fracture
- Acute (progressing) median nerve palsy
- Associated carpal dislocation

Post-treatment:
- Immediate stability
- Early mobilisation
- Strengthening after 4-6 weeks

Question 33

Healing time for fractures

Answer 33

Prerequisite for fracture healing:
1. Good blood supply
2. Strength of bone
3. Fracture site not under stress (lower limb > upper limb, shaft > joint area)

Upper limb (48484 rule):
Distal radius: 4 weeks
Radial shaft: 8 weeks
Elbow: 4 weeks
Humeral shaft: 8 weeks
Shoulder: 4 weeks

Lower limb (8168168 rule):
Hip: 8 weeks
Femoral shaft: 16 weeks
Knee: 8 weeks
Tibial shaft: 16 weeks
Ankle: 8 weeks