Supracondylar Femur Fracture (Periprosthetic) - ORIF

Pre-operative Planning

Patient Assessment

Comprehensive evaluation of three domains:

1. Patient Factors:

• Age and physiological status (typically elderly 70-85 years)
• Comorbidities: cardiovascular disease, diabetes, renal impairment, PVD
• Ambulatory status pre-fracture (independent vs assisted vs non-ambulatory)
• Bone quality assessment (DEXA if available, radiographic osteoporosis)
• Cognitive function (delirium risk, compliance with restricted weight-bearing)
• Social situation (discharge planning, home support)

2. Fracture Factors:

• Displacement and alignment (varus collapse common)
• Comminution pattern (simple vs complex metaphyseal comminution)
• Bone stock proximal and distal to fracture
• Fracture location relative to TKR component (above, at, or through component)
• Associated injuries (rare in low-energy periprosthetic fractures)
• Mechanism (low-energy fall most common)

3. Prosthesis Factors:

• Type of TKR (cruciate-retaining, posterior-stabilized, constrained)
• Component stability (CRITICAL - determines ORIF vs revision)
• Cementing technique (cemented vs uncemented, cement mantle extent)
• Age of prosthesis (recent more likely stable, older higher loosening risk)
• Reason for original TKR (primary OA better bone stock than inflammatory)
• Previous TKR complications or revisions

Imaging Protocol

Standard X-rays:

• AP and lateral of ENTIRE femur (hip to below knee)
• Include ALL hardware (proximal femoral hardware if present, entire TKR)
• Comparison views to contralateral knee for rotation reference
• Stress views if component stability uncertain

Assess on X-rays:

• Fracture pattern and classification
• Displacement and angulation
• Femoral component position and orientation
• Signs of loosening: lucency around component (>2mm), subsidence, osteolysis
• Bone stock: cortical thickness, medullary canal diameter, osteoporosis severity
• Previous cement mantle extent (affects IM nail feasibility)

CT Scan (selective indications):

• Complex comminution requiring surgical planning
• Uncertain component stability on plain films
• Coronal plane fracture extension
• 3D reconstruction for pre-operative planning and templating

Classification Systems

Lewis & Rorabeck Classification (Most Commonly Used):

Type I: Non-displaced fracture, prosthesis stable

• Initial conservative management (hinged brace, TTWB)
• Close monitoring for displacement (weekly X-rays initially)
• Convert to ORIF if displacement occurs
• Rare for this to succeed long-term in mobile patients

Type II: Displaced fracture, prosthesis stable

• ORIF with lateral locking plate = STANDARD TREATMENT
• Most common operative indication
• Good outcomes if adequate fixation achieved

Type III: Fracture with loose/failing prosthesis

• REVISION ARTHROPLASTY = STANDARD TREATMENT
• Options: long-stem revision TKR or distal femoral replacement (DFR)
• ORIF alone will FAIL (>80% failure if component loose)
• Alternative: ORIF + simultaneous component revision (complex, experienced surgeons)

Su Classification:

Type I: Proximal to femoral component (above component)

• Treat as native supracondylar fracture if sufficient distal bone
• ORIF with locking plate (easier than Type II - more distal fixation options)

Type IIA: Originates at proximal aspect of component, component stable

• ORIF with lateral locking plate
• Most challenging distal fixation

Type IIB: Originates at component, component loose

• Revision arthroplasty required

Type III: Distal to femoral component (rare, <5%)

• Intra-articular, usually associated with tibial component loosening
• Complex management, often requires revision arthroplasty

Treatment Algorithm

RORABECK TYPE I (non-displaced, stable):

• Conservative: hinged knee brace, TTWB 6-12 weeks
• Weekly X-rays initially (high displacement risk)
• Low threshold to convert to ORIF if any displacement
• Only suitable for low-demand, compliant patients

RORABECK TYPE II (displaced, stable):

• ORIF with lateral locking plate (first-line)
• Retrograde IM nail IF:
  • Adequate distal fragment (minimum 5-6cm)
  • Canal not blocked by long cement stem
  • Minimal comminution
• Consider DFR if: very elderly, severe osteoporosis, high surgical risk

RORABECK TYPE III (displaced, loose):

• Long-stem revision TKR IF:
  • Adequate distal bone stock
  • Primary loosening (not osteolysis/bone loss)
  • Experienced revision surgeon
• Distal femoral replacement IF:
  • Severe bone loss
  • Very distal fracture
  • Comminuted metaphysis
  • Elderly, low-demand (allows early weight-bearing)
• ORIF + component revision: complex, only if very experienced

Special Considerations

Severe Osteoporosis:

• Assess intra-operatively: "eggshell" cortices, poor screw purchase
• May require conversion to DFR rather than plate fixation
• High screw pullout risk even with optimal technique

Very Elderly/Low Demand:

• DFR may be superior to ORIF:
  • Single-stage surgery
  • Allows early weight-bearing
  • Avoids fixation failure risk
  • Shorter rehabilitation

Medical Optimization:

• Cardiac clearance if high-risk
• Glycemic control in diabetics
• Hold anticoagulation appropriately (bridging protocol)
• Nutritional assessment (vitamin D, calcium supplementation)
• DVT prophylaxis planning (high-risk population)

Patient Positioning

Operating Room Setup

Table Configuration:

• Radiolucent table (full-length imaging capability)
• Ensure C-arm can access from hip to below knee
• Contralateral leg in leg holder (allows comparison imaging)
• Hip bump and lateral thigh support available

Patient Position - Supine:

• Small bump (folded towel) under ipsilateral hip
  • Controls rotation (prevents excessive external rotation)
  • Facilitates reduction
• Sandbag lateral to thigh for stability during preparation
• Affected leg free-draped from iliac crest to toes
• Contralateral leg in leg holder (compare length and rotation)

Tourniquet Considerations:

• Thigh tourniquet available but CONTROVERSIAL in elderly
• Benefits: Improved visualization, easier dissection through scar
• Risks in elderly: PVD common, prolonged surgery time, reperfusion injury
• Recommendation: Avoid if PVD, use limited time (<90min) if needed
• Alternative: Meticulous hemostasis without tourniquet

Fluoroscopy Planning

C-arm Positioning:

• From contralateral side for AP
• Ensure can obtain: AP, lateral, obliques, hip view, knee view
• Check imaging quality BEFORE draping:
  • AP: entire femur, hip joint, TKR components
  • Lateral: true lateral (femoral condyles superimposed)
  • Hip: proximal plate extent and screws
  • Knee: TKR component position, distal screw relationship

Pre-operative Imaging Checklist:

• Fracture visualization on AP and lateral
• TKR component clearly visible
• Contralateral leg for rotation comparison
• Proximal femur/hip visible (assess plate length)
• Distal tibia visible (assess overall alignment)

Surgical Approach - Lateral to Distal Femur

Incision Planning

Assessment of Previous Scars:

• Previous TKR typically: midline or medial parapatellar
• Assess skin quality: thin, atrophic, previous complications?
• Plan incision to maximize perfusion, minimize tension

Two Incision Strategies:

Option 1: Utilize Existing Scar (More Common)

• Extend previous midline/medial parapatellar scar proximally
• Curve laterally in proximal extension to access lateral femur
• Advantages: Single incision, familiar anatomy
• Disadvantages: May compromise skin perfusion, longer scar

Option 2: New Lateral Incision (If Skin Concerns)

• Create separate lateral incision parallel to femur
• Maintain skin bridge >7-10cm from existing scar
• Advantages: Better skin perfusion
• Disadvantages: Multiple scars, bridge skin at risk

Typical Lateral Incision:

• Proximal: 10-15cm above fracture (mid-femur level)
• Distal: lateral epicondyle or joint line
• Total length: 20-30cm (extended exposure for plate application)
• Centered over lateral femur (ITB palpable landmark)

Superficial Dissection

Skin and Subcutaneous Layer:

• Incise with sharp knife in single pass
• CAREFUL: Elderly skin thin, fragile, poor healing
• Ligate superficial bleeding vessels meticulously
• Expect scar tissue from previous TKR

Identify and Incise ITB:

• Palpate ITB (thick fascial band on lateral thigh)
• May be adherent to underlying structures from scarring
• Longitudinal split in line with fibers
• Length: match bone exposure needed (fracture zone + proximal/distal plate)
• Ligate lateral superior genicular vessels if encountered distally

Deep Dissection

Vastus Lateralis Mobilization:

• In elderly with previous TKR, expect:
  • Atrophic, thin muscle (chronic disuse)
  • Scarred to lateral femur from previous surgery
  • May be partially detached already

Submuscular Plane Development:

• Elevate vastus lateralis ANTERIORLY off lateral intermuscular septum
• This creates plane for plate placement (submuscular)
• Use SHARP dissection through scar tissue
• PRESERVE muscle tissue (often limited in elderly)
• Blunt dissection along periosteum proximally and distally

Exposure Goals:

• Proximal: adequate for plate length (10-15cm above fracture)
• Fracture site: clear visualization for reduction
• Distal: to femoral component level (assess stability, plan screw placement)

Hemostasis:

• Meticulous as dissection progresses
• Elderly on anticoagulation = significant bleeding risk
• Cautery for small vessels, ligate larger vessels
• Consider tranexamic acid (1g IV at induction, 1g at 3 hours)

Fracture Exposure and Assessment

Fracture Site Visualization

Clear Fracture Zone:

• Evacuate hematoma (save for biology if MIPO technique)
• Minimal periosteal stripping (preserve blood supply)
• Identify major fragments (typically two main fragments, variable metaphyseal comminution)

Intra-operative Assessment:

• Fracture pattern: transverse, short oblique, comminuted
• Bone quality: "eggshell" cortices? Normal density? (critical for fixation decision)
• Distal fragment: adequate for screw fixation? Fracture extension into condyles?
• Proximal fragment: length, quality, deformity

Critical Decision Point - Bone Stock:

• If SEVERE osteoporosis with very thin cortices (eggshell):
  • Plate fixation may be futile (screw pullout inevitable)
  • Consider conversion to DFR intra-operatively
  • Discuss with patient/family if not consented pre-op
• If adequate bone stock: proceed with ORIF

TKR Component Assessment

Component Stability Testing (CRITICAL):

Pre-fixation Assessment:

• Direct visualization if component exposed
• Look for lucency at cement-bone interface
• Look for gross motion of component

Stress Testing:

• Apply varus and valgus stress to knee
• Palpate component and fracture site simultaneously
• Any component motion? (suggests loosening)
• Compare to expected normal stability

Fluoroscopic Assessment:

• Image during stress testing
• Look for component motion or fracture gapping
• Compare to pre-operative films

If Component LOOSE (Rorabeck Type III):

• STOP and RECONSIDER plan
• Options:
  1. Abort ORIF, convert to revision arthroplasty (preferred)
  2. ORIF + simultaneous component revision (complex, experienced surgeon)
  3. ORIF alone if patient too sick for revision (accept high failure risk)
• Communicate with patient/family

If Component STABLE:

• Proceed with ORIF
• Note component position for distal screw planning (blocks posterior screws)

Fracture Reduction Technique

Reduction Principles in Osteoporotic Bone

GENTLE Technique Essential:

• Osteoporotic bone fragments easily with force
• "Don't crush the egg" principle
• Accept metaphyseal comminution if major fragments aligned
• Biological bridging technique (not anatomic reduction of every fragment)

Reduction Goals

Length:

• Restore to contralateral limb length
• Measure fluoroscopically (compare landmarks to opposite side)
• Usually 1-2cm shortening acceptable (elderly, low demand)

Alignment:

• Coronal: 5-7° valgus (normal distal femur alignment)
• Sagittal: 0° (no anterior/posterior angulation)
• Axial: neutral rotation (CRITICAL - compare to contralateral)

Rotation Assessment:

• Clinical: patella orientation, epicondylar axis alignment
• Fluoroscopic: lesser trochanter profile AP view, compare to contralateral
• MALROTATION is common error - meticulous assessment

Reduction Techniques

1. Manual Traction and Manipulation:

• Longitudinal traction to restore length (gentle, sustained)
• Correct varus/valgus with medial/lateral force
• Correct anterior/posterior angulation with flexion/extension

2. Reduction Clamps:

• Pointed reduction forceps across fracture
• Large bone clamps for stability
• CRITICAL: Use PADDING under clamps (osteoporotic bone crushes)
• GENTLE compression only (no forceful crushing)
• Alternative: use clamps on plate rather than bone

3. Provisional K-wire Fixation:

• Once reduced, place 1-2 K-wires for temporary stability
• Away from planned screw locations
• Allows hands-free for plate application

4. Plate as Reduction Tool:

• Apply plate to proximal shaft and distal femur
• Use plate to maintain length, alignment, rotation (bridging technique)
• Particularly useful in comminuted metaphyseal zone
• Locking screws maintain reduction without compression

Fluoroscopic Verification

Before Plate Application:

• AP: valgus alignment, no medial/lateral translation
• Lateral: no anterior/posterior angulation, reduction acceptable
• Comparison to contralateral: rotation, length

Accept Acceptable Reduction:

• Perfect anatomic reduction often impossible in osteoporotic bone
• Acceptable: length within 1cm, alignment within 5°, rotation <10°
• Unacceptable: varus (high failure risk), malrotation >15°, shortening >2cm

Plate Selection and Application

Plate Selection Criteria

Plate Type:

• Anatomically contoured lateral distal femur locking plate
• Periprosthetic-specific plates available (optimized design)
• Fixed-angle locking screws essential (stability in osteoporotic bone)

Plate Length (CRITICAL in Periprosthetic):

• Must be LONGER than native fracture fixation
• Minimum: 6-8 cortices (3-4 screws) proximal to fracture
• Preferred in osteoporotic bone: 10-12 cortices (5-6 screws) proximal
• Rationale: distribute stress, reduce stress riser at plate end
• Too short = fixation failure at proximal plate end (common complication)

Plate Features:

• Sufficient distal holes (TKR component limits distal screw number)
• Combination of locking and non-locking holes
• Pre-contoured (minimize bending needed)
• Low profile if possible (soft tissue coverage)

Plate Positioning

Correct Position - LATERAL Cortex:

• Plate sits on true lateral cortex
• NOT anterior or posterior (causes sagittal malreduction)
• Check fluoroscopy: AP view - plate on lateral edge, Lateral view - plate superimposed on cortex

Proximal-Distal Position:

• Distal end: at or just proximal to femoral component
• Don't extend beyond component (no bone for screws)
• Proximal end: extends well above fracture (10-15cm minimum)

Plate Contouring:

• Pre-contoured plates usually fit well
• MINIMAL bending if needed (excessive bending weakens plate)
• Use gentle bending tools (plate benders), avoid notching plate
• In osteoporotic bone, plate sits ON cortex (not pressed down)

Provisional Plate Fixation:

• K-wires through plate holes to stabilize
• Or temporary cortical screws (converted to locking later)
• Allows assessment before definitive screw insertion

Screw Fixation - Proximal

Proximal Screw Strategy

Number of Screws:

• In osteoporotic periprosthetic fractures: FILL MORE HOLES than young patient
• Typically use 5-6 screws (10-12 cortices) proximal to fracture
• This is MORE than native fracture (which uses 3-4 screws, 6-8 cortices)

Working Length Principle (Modified):

• Traditional: leave 2-3 empty holes near fracture for working length
• In elderly osteoporotic: leave only 1-2 empty holes (need more stability)
• Rationale: weaker bone needs more fixation, less reliance on biology

Screw Type Mix:

• Non-locking cortical screws: can compress plate to bone if gap present
• Locking screws: fixed-angle stability, no compression needed
• Strategy: use non-locking if want compression, then locking for definitive stability

Screw Technique:

• Use fixed-angle targeting guide (attached to plate)
• Drill 3.2mm drill bit
• Bicortical purchase (maximum stability in osteoporotic bone)
• Measure carefully
• Insert locking screw (torque-limiting screwdriver)

Screw Distribution:

• Stagger screw lengths if possible (reduces stress concentration)
• Fill most proximal holes (distribute stress)
• Leave 1-2 holes empty near fracture (minimal working length)

Screw Fixation - Distal (Most Challenging)

Challenge: TKR Component Blocks Screws

Anatomy:

• TKR femoral component sits posterior on distal femur
• Blocks traditional posterior screw trajectories
• Cement mantle extends around component (very hard, breaks drills)

Consequences of Hitting Component:

• Dulls or breaks drill bit
• May damage component (cement chip, component crack)
• Screw will not advance or will break
• May need to remove screw (difficult)

Strategies for Distal Fixation

1. Anterior-to-Posterior Screws (SAFEST, FIRST CHOICE):

• Trajectory from anterior cortex toward posterior
• AWAY from component (which sits posteriorly)
• AWAY from popliteal vessels (which run posteriorly)
• Unicortical or short bicortical (stop before component/vessels)
• Most reliable distal fixation method

2. Medial-to-Lateral or Lateral-to-Medial Screws:

• If plate design includes perpendicular screw holes
• Trajectory parallel to joint line
• Avoids component in AP direction
• Not all plates have these holes

3. Through Femoral Component Pegs:

• If modular TKR with femoral pegs/lugs
• Some components allow screws through peg screw holes
• Check component specifications
• Requires precise trajectory

4. Unicortical Screws:

• If bicortical risks hitting component or vessels
• Locking unicortical screws provide SIGNIFICANT stability
• Better than no screws or risking complications

Distal Screw Technique

Pre-insertion Planning:

• Assess component position on AP and lateral fluoroscopy
• Identify "safe zones" for screw placement
• Typically anterior cortex safe, posterior risky

Drilling:

• Use targeting guide attached to plate
• 3.2mm drill bit
• FREQUENT fluoroscopy (AP and lateral)
• Check drill position before advancing
• Stop if drill encounters cement (very hard resistance)

Screw Insertion:

• Measure carefully (unicortical vs short bicortical)
• Insert locking screw
• Verify on fluoroscopy (AP and lateral)
• Ensure not penetrating component or joint

Typical Achievable Distal Fixation:

• 2-4 distal screws typical (limited by component)
• Even 2-3 well-placed screws sufficient if proximal fixation robust
• Quality more important than quantity in distal fixation

Fixation Verification

Fluoroscopic Assessment

AP View:

• Alignment: 5-7° valgus maintained
• No medial-lateral translation
• Screws not hitting component
• Length restored

Lateral View:

• No anterior-posterior angulation
• Reduction satisfactory
• Screws not penetrating posteriorly (vessels risk)
• Screws not hitting component

Oblique Views:

• Overall reduction assessment
• Hardware position

Hip View:

• Proximal plate extent
• Proximal screw position and length

Knee View:

• Distal screws relative to TKR component
• No intra-articular screw penetration

Clinical Stability Testing

Fracture Stability:

• Palpate fracture site
• No motion with gentle manipulation?
• Stable construct?

Knee Range of Motion:

• Gently flex knee to 45-60°
• Fracture remains stable?
• Avoid forced flexion (stresses distal fixation)

Length and Rotation:

• Measure length against contralateral (clinical and fluoroscopic)
• Assess rotation: patella position, epicondylar axis
• Compare to contralateral limb

Final Decision Point

If Stable and Well-Reduced:

• Proceed to closure

If Concerns About Stability:

• Inadequate distal fixation (<2 screws)
• Severe osteoporosis with poor screw purchase
• Questionable reduction
• CONSIDER: Additional fixation, bone grafting, or conversion to DFR

Augmentation Techniques (Selective)

Bone Grafting Indications

Metaphyseal Void or Comminution:

• Significant bone defect after reduction
• Comminuted metaphyseal zone with gap
• Fill with graft to support fixation and promote healing

Graft Options:

• Autograft: iliac crest (gold standard biology but donor morbidity in elderly)
• Allograft: morselized cancellous chips (avoid donor site)
• Bone graft substitutes: synthetic or biologic (e.g., calcium phosphate, DBM)

Technique:

• Pack graft into metaphyseal void through fracture site
• Minimize periosteal stripping
• Compress graft to support reduction

Cement Augmentation (Off-Label)

Rationale:

• Severe osteoporosis with poor screw purchase
• Increase pullout strength of proximal screws
• Used in some centers, NOT FDA approved for this indication

Technique:

• Mix PMMA bone cement
• Inject small amount (1-2ml) around selected proximal screws
• Before full polymerization (remain semi-liquid for minutes)
• Creates cement mantle around screw threads

Risks:

• Thermal necrosis (exothermic polymerization)
• Cement embolism (fat embolism syndrome risk)
• Infection risk (foreign material)
• Not evidence-based for this indication

Alternative:

• Better to use longer plate with more screws
• OR consider DFR if bone stock inadequate for reliable fixation

Biologics (Selective)

High Non-Union Risk Cases:

• Active smoking
• Diabetes
• Severe osteoporosis
• Open fracture or significant soft tissue injury

Options:

• BMP-2 or BMP-7 (off-label use, expensive)
• Demineralized bone matrix (DBM)
• Platelet-rich plasma (limited evidence)

Typical Approach:

• Most cases: no biological augmentation beyond addressing voids
• MIPO technique preserves fracture hematoma (biological bridge)

Wound Closure

Irrigation

Copious Irrigation:

• Minimum 3 liters normal saline
• Pulsatile lavage or bulb syringe
• Remove debris, hematoma, bone fragments
• Reduce infection risk

Antibiotic Irrigation:

• Controversial, some use bacitracin solution
• Not evidence-based for routine use

Layered Closure Technique

Deep Layer - Vastus Lateralis:

• Re-approximate to lateral intermuscular septum if possible
• Often atrophic and may not hold sutures well
• 0 or 1 absorbable suture (Vicryl)
• Interrupted or running based on tissue quality
• Don't over-tension (tissue tears in elderly)

ITB Layer:

• Close longitudinal split in ITB
• 0 or 1 absorbable suture
• Running or interrupted
• Provides strong fascial layer

Subcutaneous Layer:

• 2-0 or 3-0 absorbable suture
• Interrupted or running
• MINIMIZE DEAD SPACE (hematoma prevention)
• Careful hemostasis before closure

Skin Closure:

• Options: staples (fast, strong), interrupted sutures, subcuticular suture
• Consider skin glue reinforcement over closure
• AVOID TENSION (thin elderly skin tears easily)
• If tension present, consider relaxing incisions or alternate closure

Drain Placement

Indications:

• Large dissection
• Elderly patient (high hematoma risk)
• Expected post-operative anticoagulation
• Oozing despite meticulous hemostasis

Technique:

• 12-14Fr round drain (Hemovac or Jackson-Pratt)
• Exit separate stab incision
• Position deep to ITB layer
• Avoid direct contact with hardware

Management:

• Remove at 24-48 hours (when output <30ml per 8 hours)
• Prolonged drainage increases infection risk

Dressing and Immobilization

Sterile Dressing:

• Non-adherent layer over incision
• Absorbent gauze
• Compression wrap (gentle - avoid compartment syndrome)

Hinged Knee Brace:

• Locked in extension initially
• Provides comfort and protection
• Limits flexion stress on distal fixation
• Unlocked for ROM exercises per protocol

Post-operative Management

Immediate Post-operative Period (0-48 hours)

Pain Management:

• Multimodal analgesia (reduce opioid use in elderly)
• Scheduled acetaminophen
• NSAIDs if renal function permits (caution with bone healing)
• Opioids for breakthrough pain (minimize dose)
• Regional anesthesia (femoral nerve block) if used intra-op

VTE Prophylaxis (HIGH PRIORITY):

• Mechanical: TED stockings + intermittent pneumatic compression
• Chemical: LMWH (enoxaparin 40mg daily) OR warfarin (INR 2-2.5)
• Start within 12-24 hours post-op
• Continue minimum 6 weeks (high-risk population)
• Consider extended prophylaxis to 12 weeks

Monitoring:

• Neurovascular checks every 4 hours initially
• Compartment syndrome assessment (rare but catastrophic)
• Drain output monitoring
• Pain control adequacy
• Delirium screening (common in elderly post-op)

Drain Management:

• Monitor output
• Remove at 24-48 hours when <30ml per 8-hour shift

Early Mobilization (Days 1-7)

Bed Mobility and Transfers:

• Log roll with assistance
• Sit edge of bed day 0 or 1
• Transfer to chair with assistance

Standing and Ambulation:

• Stand day 1 with physiotherapy
• Ambulate day 1-2 with walker or crutches
• Weight-bearing per protocol (see below)

Range of Motion:

• Start day 1-2 (early ROM critical, but protected)
• Initial limitation: 0-45° for first 6 weeks
• Rationale: protect distal fixation from flexion stress
• Passive and active-assisted ROM
• CPM machine optional (traditional use, limited evidence)

Weight-Bearing Protocol (CRITICAL)

General Principle:

• MORE RESTRICTED than native distal femur fractures
• Reason: osteoporotic bone, limited distal fixation, elderly

Typical Protocol (Individualized Based on Fixation):

Weeks 0-12:

• Touch-down weight-bearing (TTWB) or Partial weight-bearing 20-30kg
• Foot contact for balance only
• Walker or crutches mandatory
• Significant upper extremity strength needed (challenging for elderly)

Weeks 12-16:

• If early callus visible on X-ray
• Advance to PWB 50% (half body weight)
• Continue walker or single crutch

Weeks 16-24 (4-6 months):

• If bridging callus on 3 cortices
• Advance to Weight-bearing as tolerated (WBAT)
• Progress to cane or no assistive device

Months 6-12:

• Full unrestricted weight-bearing
• Return to baseline activities if healed

Factors Allowing Earlier Weight-Bearing:

• Excellent bone quality (unusual in this population)
• Robust fixation (6+ distal and proximal screws)
• Simple fracture pattern

Factors Requiring Prolonged Restriction:

• Severe osteoporosis
• Limited distal fixation (<3 screws)
• Comminuted fracture
• Questionable fixation stability

Range of Motion Progression

Weeks 0-6:

• 0-45° flexion (protect distal fixation)
• Passive and active-assisted
• Quadriceps sets, ankle pumps
• Avoid active knee extension against resistance

Weeks 6-12:

• Advance to 0-90° flexion
• Continue passive and active-assisted
• Begin gentle active ROM
• Light resistance quadriceps strengthening

Weeks 12-24:

• Goal 0-120° flexion by 6 months
• Progressive active ROM
• Functional activities
• Balance and gait training

Follow-up Schedule

Week 2:

• Wound check
• Suture or staple removal
• Assess for wound complications
• Reinforce weight-bearing and ROM restrictions

Week 6:

• X-ray (AP and lateral)
• Assess: alignment maintained, early healing, hardware position
• Advance ROM to 0-90°
• Continue TTWB/PWB 20-30kg

Week 12:

• X-ray (AP and lateral)
• Assess callus formation (early bridging?)
• If progressing: advance to PWB 50%
• If no callus: continue TTWB, closer monitoring

Month 4-6:

• X-ray
• Assess for bridging callus (3 cortices minimum)
• If healed: advance to WBAT
• If delayed union: consider stimulation, continued protection

Month 6-12:

• X-ray
• Final assessment
• Most healed by 6 months, up to 12 months not uncommon
• Return to full activities if healed

Radiographic Healing:

• Periprosthetic fractures heal SLOWER than native
• Bridging callus on 3 of 4 cortices = union
• Typical: 4-6 months
• Delayed union common: up to 12 months

Rehabilitation Protocol

Quadriceps Strengthening:

• Essential for return to function
• Start with isometric sets (quad sets)
• Progress to SLR (when ROM adequate)
• Resistance exercises when healing progressing

Gait Training:

• Walker technique with TTWB/PWB
• Balance exercises (fall prevention critical)
• Progress assistive device as weight-bearing allows
• Normalize gait pattern

Functional Training:

• Transfers (bed, chair, toilet, car)
• Stairs (later, when adequate strength and healing)
• Activities of daily living
• Home safety assessment

Complications Monitoring

Fixation Failure (10-20%):

• Screw pullout, varus collapse, plate breakage
• Early signs: increased pain, loss of reduction on X-ray
• Management: revision fixation vs conversion to DFR

Non-union (10-15%):

• No progression of healing by 6 months
• Management: revision with bone grafting, compression, ± stimulation vs DFR

Infection (2-5%):

• Superficial: wound drainage, erythema - antibiotics ± debridement
• Deep: catastrophic near TKR - may require component removal, antibiotic spacer

Malunion/Malrotation (10-15%):

• Varus most common and problematic
• Rotation often not recognized until healed
• May require corrective osteotomy if symptomatic

Medical Complications (10-20%):

• MI, stroke, PE, pneumonia
• Common in elderly population
• Multidisciplinary management

Stiffness (5-10%):

• Less common than fixation failure
• Aggressive physiotherapy
• Manipulation under anesthesia if severe (caution with fixation)

Mortality (5-10% at 1 year):

• Elderly population with multiple comorbidities
• Fracture accelerates functional decline

Functional Outcome:

• 70-80% return to pre-fracture mobility IF healing successful
• Lower than native fractures
• Many never regain independence

Complications

Outcomes and Prognosis

Radiographic Outcomes

Union Rate:

• 80-90% union rate with appropriate technique
• 10-15% non-union (higher than native fractures)
• Time to union: 4-6 months typical, up to 12 months acceptable

Alignment:

• Valgus 5-7° target (normal distal femur)
• Varus malunion associated with poor outcomes and TKR failure
• Rotation within 10° acceptable

Fixation Survival:

• 80-90% fixation survival at 1 year
• 10-20% fixation failure requiring revision
• Factors predicting failure: osteoporosis severity, inadequate fixation, premature weight-bearing

Functional Outcomes

Return to Pre-fracture Mobility:

• 70-80% if fracture heals successfully
• LOWER than native distal femur fractures (90% in young patients)
• Many elderly never regain full independence

Knee Range of Motion:

• Average: 0-100° at 1 year (if healed)
• Pre-fracture ROM often limited in TKR patients
• Goal: maintain pre-fracture ROM minimum

Weight-bearing Status:

• If healed: full weight-bearing by 6-12 months
• If non-union or fixation failure: may remain restricted or require revision

Pain:

• Most patients have improved pain compared to immediate post-fracture
• Residual pain common (30-40%) - from fracture, TKR, or both
• Functional pain better predictor than rest pain

Mortality and Medical Outcomes

Mortality:

• 5-10% at 1 year (elderly population, multiple comorbidities)
• Fracture accelerates functional decline
• Medical complications common cause

Medical Complications:

• 10-20% experience MI, stroke, PE, pneumonia
• Delirium common post-operatively (30-40%)
• Functional decline even if fracture heals

Institutionalization:

• 20-30% require nursing home placement (were independent pre-fracture)
• Loss of independence common

Factors Predicting Poor Outcome

Patient Factors:

• Advanced age (>85 years)
• Multiple comorbidities
• Poor pre-fracture function
• Cognitive impairment
• Malnutrition

Fracture Factors:

• Severe comminution
• Bone loss
• Open fracture (rare)

Technical Factors:

• Inadequate fixation (plate too short, too few screws)
• Malreduction (varus, malrotation)
• Component loosening
• Complications (infection, fixation failure)

Comparison: ORIF vs DFR

ORIF Advantages:

• Preserves bone stock
• Lower infection risk
• Lower cost
• Familiar technique

ORIF Disadvantages:

• High complication rate (fixation failure 10-20%)
• Prolonged protected weight-bearing (12+ weeks)
• Slower rehabilitation
• Non-union risk (10-15%)

DFR Advantages:

• Allows early weight-bearing (immediate to 6 weeks)
• Lower fixation failure risk
• Single-stage surgery
• Predictable outcome in elderly, low-demand

DFR Disadvantages:

• Removes bone stock (limits future options)
• Higher infection risk (large implant)
• Expensive
• Technically demanding
• Aseptic loosening long-term

Current Trend:

• Increasing use of DFR in elderly, osteoporotic, low-demand
• ORIF remains standard for younger, higher-demand, adequate bone stock