Femoral Shaft Fractures

Demographics

Bimodal Age Distribution:

• Young adults (15-44): High-energy trauma (MVA, motorcycle, GSW)
• Elderly (over 65): Low-energy falls, pathological fractures

Incidence:

• 10-20 per 100,000 population per year
• Male predominance (2:1) in high-energy
• Associated injuries common in polytrauma (50%)

Mechanism:

• Motor vehicle accidents (most common)
• Motorcycle crashes
• Falls from height
• Gunshot wounds
• Pedestrian vs vehicle

High-energy mechanisms predominate in the young, low-energy falls in the elderly.

Associated Injury Screening

Polytrauma Considerations:

• Head injury common
• Chest trauma (fat embolism risk)
• Abdominal injuries
• Other long bone fractures

Complete ATLS assessment is essential in all high-energy mechanisms.

Hemorrhage Management

Expected Blood Loss:

• Closed fracture: 1-1.5 liters
• Open fracture: Higher, variable
• Can be occult - thigh swelling

Resuscitation:

• Early blood products (massive transfusion protocol if indicated)
• Avoid crystalloid over-resuscitation
• Monitor hemoglobin perioperatively
• Tranexamic acid consideration

Anticipate 1-1.5L blood loss and resuscitate accordingly.

Femoral Shaft Anatomy

Definition:

• From 5cm below lesser trochanter
• To supracondylar metaphyseal flare
• Approximately 40-50cm in length

Key Features:

• Anterior bow (apex anterior, radius approximately 120cm)
• Isthmus: narrowest point (9-12mm diameter)
• Linea aspera: posterior ridge (muscle attachments)
• Cortical bone throughout

Muscular Compartments:

• Anterior: Quadriceps (encase anterior femur)
• Medial: Adductors
• Posterior: Hamstrings

Understanding muscle attachments helps predict deformity patterns.

Vascular Anatomy

Periosteal Supply:

• Perforating branches of profunda femoris
• Supply outer 1/3 of cortex
• Preserved with careful technique

Endosteal Supply:

• Nutrient artery (branch of profunda)
• Enters posterior cortex at mid-shaft
• Supplies inner 2/3 of cortex
• Disrupted by fracture and reaming

Reaming Effect:

• Temporarily disrupts endosteal supply
• Provides local autograft (reaming debris)
• Net effect: promotes healing

The biological benefit of reaming outweighs the temporary endosteal disruption.

Mechanical Principles

Load Transmission:

• Primary weight-bearing bone of lower limb
• Experiences bending, torsion, and axial load
• Anterior bow affects nail insertion

Fracture Deformity:

• Proximal third: Flexed, abducted, ER (like subtrochanteric)
• Middle third: Variable based on muscles
• Distal third: Extension (gastrocnemius)

Nail Biomechanics:

• Intramedullary splint (load-sharing)
• Length and diameter affect stiffness
• Locking mode: static vs dynamic

Nail design must match the fracture pattern and patient factors.

Winquist-Hansen Classification

Describes comminution and guides locking strategy:

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AO/OTA Classification

32 = Femoral Shaft:

Location-Based Classification

Physical Examination

General Findings:

• Thigh swelling (blood loss indicator)
• Shortening and rotation
• Deformity visible
• Skin condition (open vs closed)

Neurovascular:

• Distal pulses (DP, PT)
• Motor: dorsiflexion, plantarflexion, toe movements
• Sensory: all dermatomes of foot
• Compartments: thigh has 3 compartments

Associated Injury Screen:

• Hip: pain, ROM if possible
• Knee: effusion, ligament stability (exam under anesthesia often needed)
• ATLS for polytrauma

Document baseline neurovascular status carefully before any intervention.

Ipsilateral Neck Fracture Screen

Screening Protocol:

1. Dedicated AP hip view
2. Internal rotation view if possible
3. CT scan if any suspicion
4. Intraoperative screening if not done preop

Missing a neck fracture is a serious complication with significant medicolegal implications.

Radiographic Protocol

Essential X-rays:

• Full-length femur (AP and lateral) - MUST include hip and knee
• AP pelvis - screen hip, compare sides
• AP and lateral knee - assess for extension, ligament injury

CT Scan Indications:

• Suspicion of ipsilateral neck fracture
• Complex fracture pattern assessment
• Pre-operative planning for difficult cases

MRI Considerations:

• Occult neck fracture if CT inconclusive
• Knee ligament injury assessment
• Usually delayed, not acute

MRI is rarely needed acutely but valuable for occult injuries.

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Laboratory Workup

Trauma Panel:

• Full blood count (baseline Hb, platelets)
• Coagulation studies (INR, PTT)
• Group and screen/crossmatch (2-4 units)
• Renal function
• Blood gas if polytrauma

Intraoperative Monitoring:

• Serial hemoglobin
• Blood product availability
• Cell saver consideration for bilateral/complex

Blood product availability is essential before starting surgery.

Surgical Planning

Measurements:

• Femoral length (compare to contralateral)
• Canal diameter at isthmus
• Neck-shaft angle (for proximal fractures)

Decision Points:

• Antegrade vs retrograde?
• Entry point (piriformis vs trochanteric)?
• Nail length and diameter?
• Locking mode (static vs dynamic)?
• Timing (immediate vs delayed)?

These decisions should be made before entering the operating room.

Core Management Principles

Gold Standard:

• Locked intramedullary nailing for virtually all femoral shaft fractures
• Reamed, locked technique
• Early fixation (within 24 hours if physiologically stable)

Goals:

• Restore length, alignment, and rotation
• Stable fixation for early mobilization
• Preserve biology where possible

Timing Considerations:

• Stable patient: Definitive IMN within 24 hours
• Unstable patient: Damage control (external fixation), convert when stable
• Early fixation reduces pulmonary complications (ARDS, fat embolism)

Early stabilization is both safe and beneficial in appropriately resuscitated patients.

Entry Point Selection

Choosing Direction

Surgical Technique

Positioning:

• Antegrade: Fracture table (supine) or lateral decubitus
• Retrograde: Supine, knee flexed over radiolucent triangle

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Key Steps (Antegrade):

1. Position, prep, drape whole leg
2. Entry point identification (trochanteric or piriformis)
3. Guidewire into femoral canal
4. Opening reamer
5. Ball-tipped guidewire across fracture
6. Sequential reaming (1-1.5mm larger than nail)
7. Nail insertion to correct depth
8. Proximal locking (under fluoro)
9. Distal locking (perfect circles technique)
10. Final rotation and length check

Rotation Assessment:

• Cortical diameter matching on fluoro
• Compare trochanter-patella relationship to other side
• Clinical assessment: hip IR/ER, foot progression angle

Multiple assessment methods should be used to confirm rotation alignment.

Damage Control Orthopaedics

Indications:

• Physiological instability (hypothermia, coagulopathy, acidosis)
• Massive transfusion ongoing
• Head injury with raised ICP
• Polytrauma with multiple priorities

Technique:

• Spanning external fixator (hip to knee or simple femoral frame)
• Stabilizes fracture, reduces bleeding
• Allows other surgical priorities

Conversion to IMN:

• When physiologically stable (24-72 hours typically)
• Plan carefully for pin site infection risk
• Remove ex-fix, prep widely, then nail

Conversion timing balances patient physiology with soft tissue and infection concerns.

Postoperative Care

Weight-Bearing:

• WBAT for most patterns with adequate fixation
• Protected for comminuted (Winquist III-IV)
• Progress based on healing

DVT Prophylaxis:

• LMWH for 4-6 weeks
• Mechanical prophylaxis
• Early mobilization critical

Follow-Up:

• 2 weeks: Wound check
• 6 weeks: X-rays, progress weight-bearing
• 3 months: Assess union
• 6 months: Confirm union, consider dynamization if delayed

Most patients return to normal activity by 4-6 months.

Antegrade Intramedullary Nailing - Standard Approach

Patient Positioning:

• Fracture table with traction (most common)
• OR lateral decubitus on radiolucent table
• Ensure adequate C-arm access

Entry Point:

• Piriformis fossa: standard trochanteric tip
• Greater trochanter: for trochanteric entry nails
• Medial to tip of GT, in line with femoral canal

Step-by-Step Technique:

1. Position and prep entire limb
2. Make 3-5cm incision proximal to GT
3. Split gluteus medius in line with fibers
4. Identify entry point with awl under fluoro
5. Open canal with reamer or awl
6. Pass guidewire across fracture
7. Ream in 0.5mm increments to 1-1.5mm above nail diameter
8. Insert nail over exchange guidewire
9. Lock proximally (targeting jig)
10. Verify length and rotation
11. Lock distally (freehand or jig)
12. Final imaging all planes

The antegrade approach is preferred for most femoral shaft fractures due to excellent biomechanical properties.

Intraoperative Technical Pearls

Reduction Techniques:

• Closed reduction with traction and manipulation
• Blocking (Poller) screws for metaphyseal extension
• Reduction clamps percutaneously for simple patterns
• Open reduction for irreducible fractures only

Avoiding Malrotation:

• Compare cortical diameters proximal and distal
• Assess lesser trochanter profile vs contralateral
• Check patella-to-tubercle alignment clinically
• Intraoperative CT if uncertain

Length Restoration:

• Pre-operative templating essential
• Compare to contralateral femur on traction
• Overlay technique on AP views
• Allow 1cm shortening in elderly if needed

Entry Point Considerations:

• Piriformis entry: true anatomic axis
• Trochanteric entry: avoids piriformis tendon damage
• Avoid varus start (medial wall breach)

Meticulous attention to rotation and length prevents the most common technical errors.

Variations and Alternatives

Retrograde Nailing:

• Indicated for: ipsilateral knee injury, pregnancy, obese patients
• Entry: intercondylar notch, anterior to PCL
• Cannot use for proximal third fractures

Plating Indications:

• Narrow canal (below 8mm)
• Existing hardware
• Periarticular extension
• Vascular repair requiring stability

External Fixation:

• Damage control in polytrauma
• Contaminated open fractures
• Temporary stabilization

Pediatric Considerations:

• Avoid piriformis entry (AVN risk)
• Lateral trochanteric entry or flexible nails
• Submuscular plating for school-age children

Technique selection depends on fracture pattern, patient factors, and available implants.

Intraoperative Complications

Malrotation:

• Most common error (especially ER)
• Prevention: careful intraoperative assessment
• Check cortical diameter, compare to other side

Guidewire/Reamer Breakage:

• Avoid excessive force
• Ensure wire doesn't kink in canal
• Retrieve broken hardware

Fracture Displacement:

• Can occur during nail insertion
• Maintain reduction during reaming and insertion
• Use fracture table traction

Iatrogenic Fracture:

• Entry point comminution
• Distal fracture at nail tip
• Avoid oversized nails in narrow canals

Careful technique and appropriate implant selection minimize these risks.

Early Complications

Fat Embolism Syndrome:

• Petechial rash, hypoxia, confusion
• Usually 24-72 hours post-injury
• Supportive treatment, early fixation is protective

Pulmonary Complications:

• ARDS in polytrauma
• Early fixation reduces risk
• Damage control if unstable

Compartment Syndrome:

• Thigh compartments can be affected
• Monitor for increasing pain, swelling
• Fasciotomy if diagnosed

Infection:

• Under 1% for closed nailing
• Higher for open fractures
• Antibiotics, debridement, may need nail exchange

Early recognition and aggressive management optimize outcomes.

Late Complications

Nonunion:

• 2-5% with modern techniques
• Risk factors: open fracture, comminution, infection
• Treatment: exchange nailing, bone graft, plate augmentation

Malunion:

• Rotation most common (ER)
• Shortening if comminuted
• Angular deformity rare with IMN
• May need derotation osteotomy

Hardware Prominence:

• Proximal screws causing trochanteric pain
• Knee pain from retrograde nail
• Remove hardware after union if symptomatic

Limb Length Discrepancy:

• From shortening at fracture site
• Shoe lift if under 2cm
• May need lengthening if significant

Prevention through careful intraoperative length restoration is key.

Immediate Postoperative (Days 0-14)

Day of Surgery:

• Neurovascular checks hourly for 4 hours
• Pain management: multimodal analgesia
• DVT prophylaxis: LMWH started 6-12h post-op
• Check post-op X-rays for implant position

Day 1:

• Sit out of bed with physio
• Commence range of motion exercises
• Weight-bearing as per fixation stability
• Most IMN: WBAT (weight-bearing as tolerated)

First 2 Weeks:

• Wound care and suture removal at 10-14 days
• Continue DVT prophylaxis (4-6 weeks total)
• Progress mobility with physio supervision
• Monitor for wound complications

Early mobilization is critical to prevent complications and optimize outcomes.

Rehabilitation Phase (Weeks 2-12)

Week 2-6:

• Progress weight-bearing per surgeon guidance
• Active ROM exercises hip and knee
• Gait training: progress from walker to crutches
• Pool exercises if wound healed

Week 6-12:

• X-ray review at 6 weeks to assess callus
• Advance to single crutch, then cane
• Strengthen hip abductors and quadriceps
• Address any developing stiffness

Red Flags to Monitor:

• Increasing pain (may indicate hardware failure)
• New deformity
• Wound drainage beyond 2 weeks
• Persistent thigh swelling

Regular clinical and radiographic review ensures early detection of problems.

Return to Function (3-6 Months)

Month 3:

• X-ray to assess union progress
• If bridging callus: advance activities
• Wean walking aids as strength permits
• Commence light gym/cycling

Month 4-6:

• Expect radiographic union by 4 months
• Return to driving when off analgesia and able to brake
• Gradual return to work (desk work earlier)
• Sport-specific rehabilitation if athlete

Hardware Removal:

• Not routine - only if symptomatic
• Wait minimum 18-24 months post-union
• Counsel re-fracture risk (refracture through screw holes)

Long-term Considerations:

• Annual review until 2 years
• Address any limb length discrepancy
• Malrotation usually well tolerated under 15 degrees

Most patients achieve excellent functional outcomes with modern fixation techniques.