O&T SC045: My Granny Broke Her Hip: Management Of Osteoporotic Fractures Flashcards
Anatomy of Hip
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
- Ligamentum teres artery
- from obturator artery / medial femoral circumflex artery (MFCA)
- not effective in adults - Intramedullary vessel (Nutrient artery)
- small contribution
Clinical features of Hip fracture
- Shortened leg
- Externally rotated
Risk factors for Hip fracture
- Increased risk of falls
- Concurrent medical illness
- Drugs - tranquillisers, alcohol
- Dementia / Sarcopenia / Visual impairment - Reduction in protective responses
- Loss of local shock absorbers
- Loss of bone strength
- Drugs - corticosteroids, anticonvulsants, thyroxine, alcohol
- Smoking
- Vit D deficiency
- Ca deficiency
- Physical inactivity
Investigations in Hip pain with normal X-ray
- Repeat X-ray (not sensitive but specific)
- CT (not sensitive but specific)
- MRI (Most sensitive + specific)
- Bone Scan (sensitive but not specific) (Tc-99m taken up by osteoblast)
***Classification of Hip fracture
This classification have different management!!!
- 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
- 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
Considerations in Fracture NOF
- ***Age
- ***Displacement
- Save the femoral head in young age / undisplaced
- Time of presentation: AVN ( 6hr)
- Patient’s general health
- Risk factors for internal fixation failure
- Old age
- Osteoporosis
- Too comminuted
- Sepsis
- Vertical fracture pattern (∵ larger shear stress)
- Delayed presentation
***Surgical treatment of Hip fracture + Garden’s classification
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)
Stable vs Unstable extracapsular fracture
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
Dynamic hip screw, Proximal femoral nail
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
Complications of Hip fracture (SpC Revision)
- Non-union
- Avascular necrosis
- Secondary OA
- Implant related complication (e.g. failure, infection)
- Immobility —> Contracture, Pneumonia, Bed sores, UTI, DVT
Fragility fracture
- 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
Osteoporosis
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
Epidemiology of Fragility fracture
- 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
***Principles of fracture treatment
- Reduction if necessary
- Immobilisation if necessary
- 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
Typical patient presentation in Fragility fracture
- Abnormal bones (very porotic)
- Comorbidities (ASA (American Society of Anesthesiology) class)
- cause / complicate fall - Polypharmacy
- Impaired physiological reserve (e.g. poor cardiopulmonary function)
- Impaired cognitive function
- Unable to unload injured extremity due to general weakness / poor balance —> must bear full weight
- Marginally independent ADL +/- live alone
Timing of surgery
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)
Surgical challenges in fixing fractures
- 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 - Fragile soft tissue
- Surgical trauma - Existing metal implant
- Limited fixation options
- Osteoporotic bone: Solutions
- Improve fixation implants for osteoporotic bone
- Alternative fixation / replacement implants
- Surgical technique advancement
- 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
- Fragile soft tissue: Solution
- Minimally invasive surgery
- Gentle retraction + manipulation
- Indirect reduction
- Intramedullary device (rather than long plates: longer wound)
Summary: Surgical intervention for elderly
- 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
Multidisciplinary rehabilitation
- Return patient to pre-fracture capabilities
- Prevent recurrent falls + fracture
- Geriatric Fracture Hip Pathway (in HA —> more standardised treatment)
- Multidisciplinary: cognition, depression, mobility, fall risk, nutrition, continence, vision
- Sustainable rehabilitation services in the community post-discharge
Address 2 tissues:
1. Bone fragility
2. Tendency to fall
Secondary prevention
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
Fall prevention
- Review +/- Adjust patient’s medication
- Anti-HT
- Psychoactive drugs
- Anticonvulsants - Evaluation of gait
- Evaluation of vision
- Evaluation of cognitive function
- Home assessment (rails, lighting, loose rugs / carpets, pets)
- Proper footwear
Standards for Fragility hip fracture care
- Admission to orthopaedic ward in 4 hours
- Surgery in 48 hours
- Prevent pressure ulcer
- Pre-op assessment by ortho-geriatrician
- Optimal surgical + non-surgical management
- Short stay in acute hospital
- Speedy discharge home
- Multidisciplinary sustainable rehabilitation service in community
- Discharged on bone protection medication
- Receive a fall assessment
- Prevention of secondary fracture
