Vancouver Classification | Stem Stability | Bone Stock
Vancouver Classification
Critical Must-Knows
- Vancouver classification based on fracture location, stem stability, bone stock
- B1 = stem stable → ORIF. B2 = stem loose → Revision
- Stem stability is KEY determinant of treatment
- Assess with X-rays (lucent lines, subsidence) and intraoperatively
- Cable plates for ORIF around stem
Clinical Pearls
- "A = Around trochanters (above stem tip)
- "B = Around stem body (B1/B2/B3)
- "C = Below stem (treat as standard fracture)
- "Cementless stems loosen differently to cemented
Clinical Imaging
Imaging Gallery




Critical Periprosthetic Hip Fracture Points
Vancouver B
B1: Stem stable, good bone → ORIF with cable plate. B2: Stem loose, good bone → Revision stem. B3: Stem loose, poor bone → Revision with augmentation (impaction grafting, megaprosthesis).
Stem Stability
KEY QUESTION: Is the stem stable or loose? Check X-rays for lucent lines, subsidence. Intraoperative assessment is definitive. If loose, cannot just fix fracture.
ORIF Technique
Cable plates for B1 and C. Cables wrap around femur and stem. Locking screws distally (unicortical if around stem, bicortical below stem).
Type C
Fracture below stem (well distal). Stem usually not involved. Treat as standard femoral fracture with plate +/- cables, or IM nail if enough space.
At a Glance
Periprosthetic hip fractures around total hip arthroplasty are classified using the Vancouver system based on fracture location, stem stability, and bone stock. The key clinical question is whether the stem is stable or loose - this determines treatment. Type B1 (stable stem, good bone) is treated with ORIF using cable plates. Type B2 (loose stem, good bone) requires revision to a longer stem. Type B3 (loose stem, poor bone) needs revision with bone augmentation (impaction grafting, megaprosthesis). Type A fractures (around trochanters) are usually treated conservatively, while Type C (below stem) is treated as a standard femoral shaft fracture.
B1-B2-B3Vancouver B Types
| B1 | Stable stem, good bone ORIF (cables) |
| B2 | Loose stem, good bone Revision stem |
| B3 | Loose stem, poor bone Revision + augment |
| B1 | Stable stem, good bone ORIF (cables) |
| B2 | Loose stem, good bone Revision stem |
| B3 | Loose stem, poor bone Revision + augment |
Hook:B1 = ORIF. B2/B3 = Revision (loose = revise)!
SLIPSSigns of Stem Loosening
| S | Subsidence Stem sinking distally over time |
| L | Lucent lines Greater than 2mm around stem |
| I | Implant migration Varus or valgus tilt |
| P | Particle debris Osteolysis from wear particles |
| S | Stem motion Gross motion on intraop assessment |
| S | Subsidence Stem sinking distally over time | P | Particle debris Osteolysis from wear particles |
| L | Lucent lines Greater than 2mm around stem | S | Stem motion Gross motion on intraop assessment |
| I | Implant migration Varus or valgus tilt |
Hook:If the stem SLIPS, it's loose - needs revision!
ABCVancouver Classification Location
| A | Around trochanters AG (greater) or AL (lesser) |
| B | Body of stem Around stem (B1/B2/B3) |
| C | Clear below stem Distal to stem tip |
| A | Around trochanters AG (greater) or AL (lesser) |
| B | Body of stem Around stem (B1/B2/B3) |
| C | Clear below stem Distal to stem tip |
Hook:ABC = Above stem, Body of stem, Clear below stem!
Overview
Periprosthetic hip fractures are fractures around a total hip arthroplasty. They are increasingly common as more THRs are performed and the population ages.
Risk Factors
Patient: Osteoporosis, female, advanced age, rheumatoid arthritis.
Implant: Revision surgery, cementless stems (higher risk than cemented), osteolysis.
Technical: Cortical perforation, stress risers.
Pathophysiology
Periprosthetic fractures result from the complex interaction between bone quality, implant characteristics, and mechanical forces.
Mechanisms of Fracture
Intraoperative fractures:
- Occur during primary or revision arthroplasty
- Femoral preparation: Broaching, reaming, or rasping can split cortex
- Implant insertion: Press-fit stems generate hoop stresses that can crack cortex
- Uncemented stems: Higher intraoperative fracture risk (1-3%) vs cemented (0.1-1%)
- Risk factors: Osteoporotic bone, tight canal, oversized components, varus positioning
Postoperative fractures (more common):
- Early (less than 5 years post-THR): Usually trauma-related, often at stress risers
- Late (greater than 5 years post-THR): Combination of bone loss and trauma
- Spontaneous: Severe osteoporosis or osteolysis may result in atraumatic fracture
Bone Changes Around Implants
Stress shielding:
- Stiff femoral stem carries load, bypassing proximal femur
- Reduced mechanical stimulus leads to bone resorption (Wolff's law)
- Proximal bone density decreases up to 30% in first 2 years
- More pronounced with:
- Fully porous-coated stems (stiffer)
- Larger diameter stems
- Younger, more active patients
- Clinical significance: Weakened bone at risk of fracture with minimal trauma
Osteolysis:
- Wear particles (polyethylene, metal, ceramic) trigger inflammatory response
- Macrophages release cytokines (TNF-α, IL-1, IL-6) activating osteoclasts
- Progressive bone resorption creates cavitary and cortical defects
- Gruen zones 1 and 7 (proximal medial and lateral) most commonly affected
- Compromises both fracture risk and fixation options
Cortical remodeling:
- Adaptive remodeling around stem alters bone architecture
- Proximal: Cortical thinning from stress shielding
- Distal (stem tip): Cortical thickening from stress concentration
- Hypertrophy: Calcar remodeling, endosteal scalloping
- Net effect: Altered bone quality makes fracture more likely
Biomechanical Factors
Stress concentration at stem tip:
- Stem tip acts as fulcrum during loading
- Bending moment greatest 2-3 cortical diameters below stem tip
- Type C fractures commonly occur at this location
- Longer, stiffer stems increase stress concentration
Torsional stress:
- Hip rotation generates torsional forces on femoral shaft
- Cemented stems: Cement-bone interface can fail in torsion
- Uncemented stems: Bone-implant interface may fail if not well-fixed
- Spiral fractures result from excessive torsion
Cyclic loading:
- Repeated loading cycles cause fatigue micro-damage
- Normally repaired by bone remodeling
- If damage accumulates faster than repair: stress fracture
- May present as impending fracture with progressive pain
Anatomy and Biomechanics
Understanding the anatomy of the proximal femur and hip arthroplasty is essential for classifying and managing periprosthetic fractures.
Proximal Femoral Anatomy
Bone anatomy:
- Greater trochanter: Insertion of hip abductors (gluteus medius, gluteus minimus). Fractures here (Type AG) affect abduction strength.
- Lesser trochanter: Insertion of iliopsoas. Avulsion (Type AL) may indicate underlying osteolysis and stem loosening.
- Femoral shaft: Cortical bone tube surrounding the stem. Bone quality critical for fixation.
- Calcar: Medial cortex at femoral neck base, often resected or resorbed around stems.
Vascular supply:
- Femoral head blood supply disrupted by arthroplasty (not relevant to fracture healing)
- Femoral shaft: Nutrient artery plus periosteal blood supply
- Fracture healing relies on periosteal and endosteal blood supply
- Extensive soft tissue stripping during ORIF may compromise healing
Hip Arthroplasty Components
Femoral stem types:
- Cemented: Cement mantle transmits forces to bone. Fracture through cement or at cement-bone interface. Generally more stable initially.
- Uncemented: Press-fit, relies on bone ingrowth. May have extensive porous coating (fully coated) or proximal coating (proximally coated). Stress shielding can weaken proximal bone over time.
Stem geometry:
- Straight stems: Easier to bypass with long revision stems
- Curved/anatomic stems: May limit revision options
- Modular stems: Allow length adjustment but have junction points that may fail
Biomechanical Considerations
Forces on proximal femur:
- Hip joint reaction force: 3-5x body weight during walking
- Abductor muscle force: Stabilizes pelvis in single-leg stance
- Torsional forces: Rotational stress on femoral shaft
- Bending moments: Anterior bow of femur creates bending stress
Effect of stem on bone stress:
- Stress shielding: Stiff stem bypasses proximal bone, reducing load. Leads to bone resorption (Wolff's law). Common in fully coated stems.
- Stress concentration: Stem tip acts as stress riser. Type C fractures often occur 2-3 cortical diameters below stem tip.
- Cortical windows: Surgical defects (e.g., cerclage wire holes, screw holes from prior surgery) create weak points.
Fracture stability determinants:
- Stem fixation: Loose stem cannot support ORIF. Must revise if loose.
- Bone stock: Poor bone (osteoporosis, osteolysis, radiation) reduces healing potential and screw purchase.
- Fracture pattern: Transverse fractures more stable than comminuted or spiral patterns.
Clinical Assessment
Thorough clinical assessment guides diagnosis, classification, and treatment planning.
History
Mechanism of injury:
- Low-energy trauma: Fall from standing height most common. Indicates pathological fracture through weakened bone.
- High-energy trauma: Rare but possible (MVA). May have associated injuries.
- Spontaneous: Severe osteoporosis or osteolysis may cause atraumatic fracture.
Pain characteristics:
- Acute onset: Suggests acute fracture
- Chronic/progressive pain: May indicate impending fracture or loosening
- Pain location: Groin (hip), thigh (shaft), knee (referred from hip)
Functional history:
- Pre-injury mobility: Walking aids, distance, independence
- Time since THR: Recent vs remote (affects loosening likelihood)
- Previous revisions: Higher risk of bone loss and complications
- Reason for THR: Osteoarthritis, fracture, inflammatory arthritis (affects bone quality)
Medical history:
- Osteoporosis: Fragility fractures, DEXA scan results, current treatment
- Medications: Bisphosphonates, steroids, anticoagulation
- Comorbidities: Cardiac, respiratory, renal disease (affects surgical risk)
- Smoking, alcohol: Impair bone healing
Physical Examination
Inspection:
- Deformity: Shortening, rotation (usually external rotation if displaced)
- Swelling: Thigh swelling common, ecchymosis may appear after several days
- Surgical scars: Previous hip incisions (lateral, posterior, anterolateral)
- Leg length: Measure from umbilicus to medial malleolus (compare to contralateral)
Palpation:
- Tenderness: Localized to fracture site (trochanteric, shaft, distal thigh)
- Crepitus: May be palpable with gentle manipulation
- Soft tissue: Check for tense compartments (rare but possible)
Range of motion:
- Hip ROM: Painful and limited. Do not force motion if fracture suspected.
- Knee ROM: Check to rule out ipsilateral knee injury
Neurovascular examination (CRITICAL):
- Femoral artery: Palpate femoral, popliteal, dorsalis pedis, posterior tibial pulses
- Femoral nerve: Test quadriceps strength (knee extension), sensation over anterior thigh
- Sciatic nerve: Test ankle dorsiflexion (deep peroneal), plantarflexion (tibial), sensation
- Document carefully: Baseline neurovascular status essential for medicolegal reasons
Clinical Pearl
Sciatic nerve palsy can occur with periprosthetic fractures, especially posterior fracture-dislocations or during revision surgery. Always document motor (ankle dorsiflexion/plantarflexion) and sensory examination. Sciatic nerve injury dramatically worsens prognosis.
Systems Assessment
Medical optimization:
- Cardiorespiratory fitness: Exercise tolerance, functional capacity
- Anemia: Common in elderly, may need pre-op transfusion
- Anticoagulation: Warfarin, DOACs - plan reversal for surgery
- Nutrition: Albumin, protein-calorie malnutrition impairs healing
Frailty assessment:
- Cognitive function: Delirium risk, ability to comply with weight-bearing restrictions
- Social support: Home situation, carers, discharge planning needs
- Goals of care: Some patients may decline surgery if severe comorbidities
Investigations
Systematic imaging and laboratory investigations establish diagnosis, guide classification, and inform treatment planning.
Plain Radiography
Essential views:
- AP pelvis: Assesses both hips, allows comparison to contralateral side. Shows acetabular component, pelvic discontinuity if present.
- AP hip: Centered on affected hip, better visualization of stem and proximal femur.
- Lateral hip: Cross-table or frog lateral. Shows anterior/posterior displacement, stem position in sagittal plane.
- Full-length femur: AP and lateral of entire femur from hip to knee. Essential to see entire prosthesis and exclude distal fracture.
Radiographic assessment (Vancouver classification):
1. Fracture location:
- Type A: Fracture line involves trochanters (AG = greater, AL = lesser). Stem tip uninvolved.
- Type B: Fracture around or at level of stem. Most common and challenging.
- Type C: Fracture well below stem tip. Prosthesis not directly involved.
2. Stem stability (CRITICAL for B1 vs B2 distinction):
Signs of loose stem:
- Subsidence: Stem has migrated distally compared to immediate post-op X-rays. Measure distance from lesser trochanter to stem shoulder.
- Lucent lines: Radiolucent line around stem greater than 2mm, especially if progressive or circumferential.
- Cement mantle fracture: Broken cement indicates stem loosening (cemented stems).
- Varus/valgus tilt: Stem alignment changed from original position.
- Pedestal formation: Bone formation at stem tip blocking further subsidence (indicates prior loosening).
Signs of stable stem:
- No subsidence: Stem position unchanged from post-operative X-rays.
- Bone ingrowth: Spot welds, cortical hypertrophy, trabecular remodeling (uncemented stems).
- Intact cement mantle: No fracture lines in cement (cemented stems).
- No lucent lines: Or only thin, non-progressive radiolucent lines less than 1mm.
3. Bone stock:
- Good bone: Adequate cortical thickness, normal bone density, minimal osteolysis.
- Poor bone: Severe osteoporosis, extensive osteolysis (especially Gruen zones 1, 7, 8), cortical thinning, cavitary defects.
Comparison X-rays Essential
Always obtain previous post-operative X-rays for comparison. Without these, assessing stem stability and subsidence is very difficult. Contact the hospital/surgeon who performed the THR to obtain historical imaging.
Advanced Imaging
CT scan:
- Indications: Complex fracture patterns, assess bone stock, surgical planning for revision, evaluate cement mantle.
- Advantages: Better visualization of fracture displacement, bone defects, osteolysis. 3D reconstructions helpful for complex cases.
- Limitations: Metal artifact from prosthesis. Metal artifact reduction software (MARS) improves image quality.
MRI:
- Rarely indicated for acute fractures (metal artifact prohibitive)
- Possible uses: Assess soft tissues (muscle tears), occult fractures, infection (if suspected)
Bone scintigraphy/SPECT-CT:
- Not routine for acute fractures
- Possible use: Differentiate fracture from loosening in chronic pain, assess for infection
Laboratory Investigations
Routine blood tests:
- FBC: Hemoglobin (anemia common, may need transfusion), WCC (infection screen)
- U&E: Renal function (important for surgical planning, contrast if CT needed)
- Coagulation: INR if on warfarin, assess bleeding risk
- Bone profile: Calcium, phosphate, ALP (osteoporosis/metabolic bone disease screen)
- CRP/ESR: Elevated in fracture, but very high levels raise infection concern
Infection screen (if any suspicion of prosthetic joint infection):
- CRP and ESR: Elevated in infection but also in fracture
- Aspiration: If infection suspected, aspirate hip under image guidance for cell count, culture, alpha-defensin
- Synovial fluid analysis: WCC greater than 3000 cells/μL or PMN greater than 80% suggests infection
Bone health assessment:
- Vitamin D: Deficiency common in elderly, correct before surgery
- PTH: If hypercalcemia or renal dysfunction
- DEXA scan: May be arranged electively post-operatively to guide osteoporosis treatment
Differential Diagnosis
The painful arthroplasty with a possible fracture has important mimics. Missing infection or loosening before fixing a fracture is a classic exam (and clinical) trap.
Differential Diagnosis of the Painful THA with Suspected Periprosthetic Fracture
| Diagnosis | Key clue | Decisive test | Why it matters |
|---|---|---|---|
| Periprosthetic fracture | Acute pain after a fall, deformity, cortical break on X-ray | Full-length femur radiographs +/- CT | Drives the Vancouver/UCS treatment algorithm |
| Aseptic stem loosening (no fracture) | Chronic start-up thigh pain, no clear injury | Serial X-rays: subsidence, progressive lucent lines, pedestal | Loose stem mandates revision even without a fracture - and upgrades a B1 to B2 |
| Periprosthetic joint infection | Rest/night pain, warmth, raised CRP/ESR, sinus | CRP/ESR, image-guided aspiration (cell count, culture, alpha-defensin) | Changes plan to debridement or staged revision; never implant into sepsis |
| Stress / insufficiency fracture (impending) | Progressive pain, no displaced cortical break, stress riser | Repeat X-ray, CT, bone scan/SPECT-CT | Prophylactic fixation prevents catastrophic completion |
| Trochanteric bursitis / abductor tear | Lateral pain, weak abduction, no fracture line | Examination +/- ultrasound or MARS MRI | Non-operative or soft-tissue problem - avoid unnecessary fixation |
| Osteolysis / impending pathological fracture | Gruen-zone lysis, polyethylene wear | X-ray, CT for defect mapping | Bearing exchange and grafting before fracture occurs |
Vancouver Classification
Vancouver Classification System
| Type | Location | Stem Status | Bone Stock | Treatment |
|---|---|---|---|---|
| A (AG) | Greater trochanter | Stable | N/A | Conservative (unless displaced) |
| A (AL) | Lesser trochanter | Stable | N/A | Conservative (check for loosening) |
| B1 | Around stem | Stable | Good | ORIF with cable plate |
| B2 | Around stem | Loose | Good | Revision to long stem |
| B3 | Around stem | Loose | Poor | Revision + augmentation |
| C | Below stem tip | Stable | Variable | Standard ORIF or IM nail |
Stem Stability Assessment
Critical Decision Point: The distinction between B1 and B2 determines treatment (ORIF vs revision). Always confirm stem stability intraoperatively - X-ray findings can be misleading. If uncertain, assume B2 (loose) and plan for revision. It is safer to revise a stable stem than ORIF a loose one.
Type A (Trochanters)
AG: Greater trochanter fracture. AL: Lesser trochanter fracture.
Usually conservative treatment unless significant displacement affecting abductor function (AG) or suggests stem loosening (AL avulsion from osteolysis).
Type B (Around Stem)
B1: Fracture around stem, stem STABLE, adequate bone stock.
- ORIF with cable plate (cerclage cables + plate).
B2: Fracture around stem, stem LOOSE, adequate bone stock.
- Revision to longer stem +/- ORIF.
B3: Fracture around stem, stem LOOSE, poor bone stock.
- Revision with augmentation (impaction grafting, allograft struts, tumor prosthesis if severe).
Type C (Below Stem)
Fracture distal to stem (not involving prosthesis directly).
Treat as standard femoral shaft fracture: Plate (with cables proximally if needed) or IM nail (if space allows above fracture for nail entry).
Management Pathway

Periprosthetic Hip Fracture Management Algorithm
History: Mechanism (low energy = pathological), pain severity, ambulatory status pre-injury, medical comorbidities.
Examination: Neurovascular status, wound (open fracture rare), leg length/rotation, implant type/age.
Imaging: AP pelvis + lateral hip X-rays. Compare to previous post-op films if available.
Determine fracture location: A (trochanter), B (around stem), C (below stem).
Assess stem stability: Look for lucent lines (greater than 2mm), subsidence, varus tilt, cement mantle fracture.
Evaluate bone stock: Gruen zones, osteolysis, cortical thickness.
Classification drives treatment: B1 vs B2 is the critical distinction.
B1 (stable stem): Plan ORIF - cable plate system, cables + screws, lateral approach.
B2/B3 (loose stem): Plan revision - long uncemented stem, possible augmentation (struts, impaction grafting).
Type C: Standard femoral fracture fixation - plate or nail if space permits.
Prepare: Blood available, implants/instruments ready, consider cell saver.
Confirm classification intraoperatively: Test stem stability under direct vision.
B1: ORIF with cables (proximal) + locking screws (distal). Unicortical around stem.
B2/B3: Remove loose stem, revision with long cementless bypass stem (4-6 inches past fracture).
Augmentation for B3: Strut allografts, impaction grafting, or proximal femoral replacement.
Weight-bearing: Protected (toe-touch to partial) for 6-12 weeks, then progress per X-ray union.
Monitoring: Serial X-rays at 6 weeks, 12 weeks, 6 months. Check for union, subsidence, loosening.
Complications: Nonunion (5-10% for ORIF), re-fracture, infection, dislocation (revision), implant failure.
Rehabilitation: Physical therapy, gait training, falls prevention, osteoporosis treatment.
Management
Indications: Vancouver B1 (stable stem), Vancouver C.
Technique:
- Lateral approach
- Cable plate (Dall-Miles or similar)
- Cerclage cables around stem/bone and plate
- Unicortical locking screws around stem (cannot penetrate stem)
- Bicortical screws below stem
Principles: Bypass fracture with 2-3 cables above and screws 2-3 cortical diameters below.
Post-op: Protected weight-bearing 6-12 weeks. Monitor union.
Surgical Techniques Comparison
| Feature | ORIF (B1/C) | Revision Stem (B2) | Revision + Augmentation (B3) |
|---|---|---|---|
| Indication | Stable stem OR below stem | Loose stem, good bone stock | Loose stem, poor bone stock |
| Approach | Lateral | Lateral or posterolateral | Extended lateral or transfemoral |
| Fixation | Cable plate + screws | Long uncemented stem | Long stem + struts/grafts/megaprosthesis |
| Stem bypass | N/A (stem retained) | 4-6 inches past fracture | Entire proximal femur if PFR |
| Augmentation | Cables only | May add struts | Struts, impaction grafting, or PFR |
| Weight-bearing | TDWB 6-12 weeks | TDWB/PWB 6-12 weeks | TDWB 12+ weeks |
| Union rate | 90-95% | 85-90% | 70-80% |
| Complication risk | Low-moderate | Moderate | High |


Complications
Periprosthetic hip fractures and their treatment carry significant complication risks, both from the fracture itself and the surgical management required.
Nonunion
Incidence: 5-10% after ORIF, higher in revision surgery. Risk factors: Poor bone quality, inadequate fixation, radiation therapy, loose stem. Management: Revision to long stem with bone grafting, or conversion to arthroplasty if severe.
Infection
Risk: 2-5% for ORIF, 5-15% for revision surgery. Elderly patients with comorbidities at higher risk. Prevention: Perioperative antibiotics, meticulous technique. Treatment: Debridement +/- implant retention vs two-stage revision depending on timing and organism.
Re-fracture
Incidence: 3-8%, typically at plate/nail ends (stress riser). Prevention: Ensure adequate fixation length bypassing lesions. Management: Extension of fixation or revision to longer implant. Consider bone quality and patient factors.
Neurovascular Injury
Sciatic nerve: At risk in posterior approaches and revision surgery (1-2%). Femoral vessels: Anterior cortical penetration risk. Prevention: Careful surgical technique, avoid over-retraction. Management: Early recognition, nerve exploration if deficit.
Dislocation
Incidence: 2-10% after revision arthroplasty, higher with proximal femoral replacement. Risk factors: Abductor deficiency, component malposition, multiple revisions. Management: Closed reduction, consider constrained liner or dual mobility cup for recurrent cases.
Implant Failure
Causes: Inadequate fixation, bone loss progression, screw pullout, plate breakage. Risk factors: Poor bone quality, inadequate construct, patient non-compliance. Management: Revision surgery with improved fixation, cement augmentation, or conversion to arthroplasty.
Prevention Strategies
Key prevention measures: Adequate fixation length (bypass fracture/lesion by 2-3 cortical diameters), cement augmentation in poor bone, protected weight-bearing until union, treatment of osteoporosis, early recognition and management of complications.
Medical Complications
Thromboembolic events: DVT/PE risk 2-5% despite prophylaxis. Elderly patients with prolonged immobility at highest risk. Mechanical and pharmacological prophylaxis essential.
Cardiopulmonary complications: MI, pneumonia, respiratory failure more common in elderly patients undergoing revision surgery. Medical optimization and early mobilization critical.
Mortality: 30-day mortality 2-5%, one-year mortality 10-20%. Higher in elderly, comorbid patients. Comparable to native hip fractures. Early surgery and medical optimization improve outcomes.
Controversies and Areas of Uncertainty
Periprosthetic hip fracture management has several genuinely unresolved questions - useful for the higher viva marks.
ORIF vs revision for B1/C
Even with a confirmed stable stem, comparative data show plate ORIF carries a higher surgery-related complication rate than revision (Laurer 2011), and registry mortality data favoured revision over ORIF for type B (Bhattacharyya 2007). Many surgeons now revise borderline cases - but ORIF remains correct for a truly stable stem with good bone.
The unreliable B1/B2 distinction
Radiographic B1 vs B2 agreement is only moderate-substantial (kappa ~0.68, Naqvi 2012). A proportion of fractures classified B1 on X-ray are loose intraoperatively. Hence the maxim: confirm stem stability in theatre, and if in doubt, treat as B2.
Cemented vs cementless revision stem
Long cementless modular tapered-fluted stems dominate, but cementing into an osteoporotic or fractured femur risks extravasation and embolism. Optimal fixation in very poor bone remains debated; impaction grafting retains advocates.
Weight-bearing after fixation
Traditional protected weight-bearing competes with the fragility-fracture principle of immediate full weight-bearing. Construct- and patient-specific decisions prevail; high-quality evidence defining safe early loading is lacking.
Vancouver vs Unified Classification System
The UCS (A-F) extends Vancouver to all implants and joints with good reliability (Van der Merwe 2014). Whether it should fully replace Vancouver in everyday hip practice is still in transition - know both.
Role of proximal femoral replacement
PFR gives immediate stability and early mobility for B3 in the frail elderly, but at the cost of higher dislocation and infection rates and abductor compromise. Thresholds for PFR versus biological reconstruction (struts/impaction grafting) are not standardised.
Postoperative Care and Rehabilitation
Successful outcomes require structured postoperative care addressing both the fracture and the underlying prosthesis.
Postoperative Rehabilitation Protocol
Pain management: Multimodal analgesia (paracetamol, NSAIDs if safe, opioids as needed). Regional techniques where appropriate.
Mobilization: Early mobilization critical. Weight-bearing status depends on fixation:
- B1 ORIF: Touch/partial weight-bearing (10-20kg) for 6-12 weeks
- B2/B3 revision: Touch/partial weight-bearing for 6-12 weeks, may progress based on construct
- Type C: Partial weight-bearing, progress as tolerated
Thromboprophylaxis: LMWH or rivaroxaban for minimum 35 days. Mechanical prophylaxis (TED stockings, pneumatic compression).
Wound care: Monitor for signs of infection. Drain removal when output less than 30mL/24hr.
Physiotherapy: Gait training with aids, hip range of motion, isometric strengthening. Avoid hip flexion greater than 90 degrees initially.
Radiographs: 6-week X-rays to assess alignment, fixation, early union. Look for hardware loosening, subsidence.
Weight-bearing progression: May advance to partial weight-bearing (30-50% body weight) if X-rays satisfactory and pain controlled.
Osteoporosis treatment: Initiate if not already on treatment. Calcium/vitamin D supplementation, consider bisphosphonates or denosumab.
Radiographs: 12-week X-rays critical. Assess for:
- Callus formation (ORIF cases)
- Stem stability (revision cases)
- Hardware integrity
- Alignment maintenance
Weight-bearing: Progress to weight-bearing as tolerated if union progressing. Full weight-bearing by 12 weeks for most B1 ORIF if united.
Strengthening: Progressive resistance exercises for hip abductors, extensors, quadriceps. Pool therapy if available.
Radiographs: 6-month X-rays. Should see union in ORIF cases, stable fixation in revision cases.
Functional goals: Independent ambulation, stairs, return to activities of daily living. Gait aids may still be needed.
Driving: May resume when safely able to perform emergency stop (typically 6-8 weeks, check insurance requirements).
Return to work: Depends on occupation. Sedentary work 6-12 weeks, physical work 3-6 months.
Annual review: Monitor for late complications (loosening, periprosthetic osteolysis, further fractures).
Osteoporosis management: Continue long-term. DEXA scan to monitor bone density. Treat underlying causes.
Falls prevention: Home assessment, balance training, review medications, treat visual/vestibular issues.
Surveillance: Educate patient on warning signs requiring urgent review (pain, deformity, wound issues).
Discharge Planning
Equipment needs: Elevated toilet seat, shower chair, reaching aids, walking frame or crutches.
Home modifications: Remove trip hazards, install grab rails, ensure bedroom/bathroom on same level if possible.
Support services: Consider home care package, meals on wheels, community physiotherapy. Involve occupational therapy.
Patient education: Hip precautions (avoid low chairs, crossing legs), weight-bearing restrictions, signs of complications, when to seek help.
Evidence Base
Vancouver Classification (Duncan & Masri, 1995)
- Original description of the Vancouver classification system
- Stratifies fractures by location, stem stability, and bone stock
- Type B subdivided into B1 (stable), B2 (loose, good bone), B3 (loose, poor bone)
- Became the gold-standard framework guiding the treatment algorithm worldwide
Vancouver Reliability & Validity (Naqvi et al, 2012)
- Six observers reviewed radiographs of 45 patients on two occasions
- Interobserver agreement substantial (kappa 0.69 consultants, 0.61 trainees)
- Intraobserver kappa 0.74 to 0.90 (substantial)
- Type B subgroup (B1/B2/B3) agreement 81% (kappa 0.68) on radiographs alone
Unified Classification System Field Test (Van der Merwe, Haddad & Duncan, 2014)
- International panel of 10 experts and 10 trainees, two reading rounds
- Interobserver reliability substantial (kappa 0.74 experts, 0.77 pre-experts)
- Intraobserver reliability near-perfect (weighted kappa 0.88 to 0.90)
- UCS extends the Vancouver A-F system to any implant, bone, and joint
ORIF vs Revision for Stable-Stem B1/C (Laurer et al, 2011)
- 32 stable-stem fractures: 16 ORIF (plate) vs 16 revision arthroplasty
- Functional outcome (Timed Up and Go) similar between groups
- Surgery-related complications significantly higher after ORIF (10 vs 3, p=0.03)
- Authors warn misreading a B2 (loose) as B1 causes ORIF failure
Loose-Stem Burden: Swedish Hip Arthroplasty Register (Lindahl et al, 2005)
- 1049 postoperative periprosthetic femoral fractures (1979-2000)
- Majority of LATE periprosthetic fractures occurred around a LOOSE stem
- Implant-related factors significantly associated with fracture risk
- Historically poor outcomes: low survivorship, high complication rate
Mortality After Periprosthetic Femoral Fracture (Bhattacharyya et al, 2007)
- 106 surgically treated periprosthetic femoral fractures
- One-year mortality 11% - similar to native hip fracture, far above primary THA (2.9%)
- Surgery delayed over two days associated with higher one-year mortality (p=0.0007)
- For type B: revision arthroplasty 12% vs ORIF 33% one-year mortality (p=0.03)
Bone Augmentation for B3 (Tsiridis et al, 2007)
- Narrative review of bone augmentation strategies for deficient proximal femur
- Allograft is the workhorse: morsellised (impaction) or structural (strut / whole proximal femur)
- Strut onlay grafts augment cortical bone; proximal femoral replacement substitutes for it
- Risks: immune reaction, disease transmission, delayed cortical revascularisation
Exam Viva Scenarios
Use these scenarios to practise clinical reasoning and management decisions
Scenario 1: Periprosthetic Fracture
"A patient with a THR falls and has a fracture around the mid-stem. X-rays show the stem is well-fixed with no lucency. How do you classify and manage?"
Scenario 2: Vancouver B3 with Poor Bone Stock
"An 82-year-old woman with a THR from 15 years ago falls. X-rays show a fracture around the stem with significant stem loosening and extensive osteolysis. There is minimal remaining cortical bone in the proximal femur. What is your classification and surgical plan?"
Scenario 3: Intraoperative Surprise - B1 or B2?
"You are fixing what you thought was a Vancouver B1 fracture with planned ORIF. During surgery, when you test the stem, you find it has some motion. What do you do?"
MCQ Practice Points
Clinical Pearl
Q: What is the Vancouver classification of periprosthetic femoral fractures?
A: Type A: Trochanteric (AG greater, AL lesser). Type B1: Around stem, stem stable. Type B2: Around stem, stem loose, adequate bone. Type B3: Around stem, stem loose, poor bone stock. Type C: Below stem tip. Classification guides treatment: B1 - ORIF; B2/B3 - revision with long stem; C - standard fixation.
Clinical Pearl
Q: How do you assess stem stability in a Vancouver B periprosthetic fracture?
A: Radiographic signs of loosening: Subsidence, varus migration, progressive radiolucent lines greater than 2mm, cement mantle fracture, particle debris. Intraoperatively: Inability to impact stem, gross motion. Preoperative planning: Serial radiographs showing migration. If uncertain, assume B2 (loose) and plan for revision - safer to revise a stable stem than ORIF an unstable one.
Clinical Pearl
Q: What is the treatment algorithm for Vancouver B1 periprosthetic fractures?
A: B1 (stable stem, good bone): ORIF with plates - use cerclage wires/cables proximally, locking screws distally. Consider anterior locking plate or cable-plate constructs. Goal: Protect well-fixed stem while achieving fracture union. Long-stemmed revision NOT required if stem truly stable. Union rates over 90% with appropriate fixation.
Clinical Pearl
Q: What reconstruction options exist for Vancouver B3 fractures?
A: B3 (loose stem, poor bone): Long uncemented extensively porous-coated stem (bypass fracture by 2 cortical diameters), proximal femoral replacement (tumor prosthesis) for severe bone loss, allograft-prosthetic composite. Cement contraindicated with poor bone stock. May require structural allograft for severe deficiency.
Clinical Pearl
Q: What are risk factors for periprosthetic hip fractures?
A: Patient factors: Osteoporosis, female sex, advancing age, rheumatoid arthritis, previous revision. Implant factors: Uncemented stems higher intraoperative risk, cemented stems higher postoperative risk (stress risers at cement tips). Technical factors: Aggressive reaming, eccentric stem placement, cortical perforation. Incidence increasing with aging THA population.
Guidelines, Registries & Global Practice
Global Epidemiology
- Periprosthetic femoral fracture is now among the leading indications for revision THA worldwide, rising as the primary arthroplasty population ages.
- Swedish Hip Arthroplasty Register: postoperative incidence approximately 0.4% after primary THA and 2.1% after revision THA, increasing from roughly 1.0 to 1.4 per 1000 primary THRs over the study era.
- Cementless (uncemented) stems carry the higher INTRAoperative fracture risk (hoop stress on press-fit); cemented stems carry relatively more LATE fractures at the cement-tip stress riser.
- Most LATE periprosthetic fractures occur around an already-loose stem (Swedish register), which is why a high proportion of type B fractures prove to be B2/B3.
Side-by-Side Guidance
Society / Source Positions
| Source | Emphasis | Practical recommendation |
|---|---|---|
| BOA / BOAST (UK) | Combined ortho-geriatric, fragility-fracture pathway | Treat like a hip fracture - early senior-led surgery, medical co-management, definitive fixation that permits immediate full weight-bearing where possible |
| AAOS (US) | Evidence-based work-up and classification-led treatment | Exclude infection/loosening; ORIF stable stems, revise loose stems; treat underlying osteoporosis |
| AO Foundation | Construct mechanics and fixation principles | Locked plate plus cerclage, adequate working length, bypass stem tip; unicortical/locking-attachment or cables at stem level |
| EFORT / European consensus | Unified Classification System (UCS A-F) and revision technique | Adopt UCS terminology; long cementless modular revision stem for loose stems, augmentation for bone loss |
Registry Insights
- National registries (Swedish/SHAR, NJR England & Wales, AOANJRR Australia, AJRR US, Norwegian, NZJR) all record periprosthetic fracture as a discrete revision indication with rising frequency.
- Implant design influences risk: collarless polished tapered cemented and certain cementless designs differ in fracture pattern and timing; registries track these signals.
- Long cementless bypass stems dominate revision for loose stems; modular proximal femoral replacement is increasingly used for B3 with unreconstructable bone, especially in the frail elderly.
High- vs Limited-Resource Practice
- Well-resourced centres: pre-operative CT, full revision implant inventory (long modular stems, struts, megaprostheses), cell salvage, ortho-geriatric co-management, and tertiary referral pathways.
- Limited-resource settings: emphasis on robust plate-cerclage ORIF for stable stems and standard fixation for type C; revision implants and structural allograft may be scarce, so accurate B1 vs B2 triage and appropriate transfer are critical to avoid predictable ORIF failure on a loose stem.
- Universal priorities everywhere: early surgery, fracture-permitting weight-bearing, infection exclusion, and treatment of the underlying osteoporosis that drove the fragility fracture.
PERIPROSTHETIC HIP FRACTURE
Clinical summary
Vancouver Classification
- •A: Trochanters (AG/AL) - conservative
- •B: Around stem
- •C: Below stem - standard ORIF
Vancouver B
- •B1: Stable stem → ORIF (cable plate)
- •B2: Loose stem, good bone → Revision
- •B3: Loose stem, poor bone → Revision + augment
Key Principle
- •Stem stability is KEY
- •Check X-rays for lucency/subsidence
- •Confirm intraoperatively
ORIF Technique
- •Cable plate system
- •Cables around bone and stem
- •Unicortical screws around stem