Volar Approach to Distal Radius

Why This Approach Dominates Distal Radius Surgery

The volar approach to the distal radius has achieved near-universal adoption for ORIF of distal radius fractures, representing one of the most dramatic surgical paradigm shifts in modern orthopaedics:

The Revolution (1990s-2000s):

• Pre-2000: Dorsal plating standard (via dorsal approach) - high extensor tendon rupture rates (10-15%), prominent hardware, poor cosmesis
• 2000-2005: Volar locked plating introduced (Orbay, Jupiter) - fixed-angle screws prevent collapse, low-profile plates reduce tendon irritation
• 2005-Present: Volar approach becomes the dominant operative approach worldwide - the large majority of distal radius ORIF is now performed volarly across UK, European, North American and Asia-Pacific practice

Three Reasons Volar Plating Won:

1. Biomechanical Superiority: Fixed-angle (locked) screws resist dorsal collapse (most common deformity in Colles fractures) better than dorsal non-locked plates
2. Soft Tissue Friendly: Volar surface has pronator quadratus muscle coverage - acts as biological barrier between plate and flexor tendons (dorsal surface is subcutaneous - no muscle coverage)
3. Early Mobilization: Stable fixation allows immediate wrist ROM - reduces stiffness (critical in elderly patients prone to frozen wrist)

Global Epidemiology and Practice: Distal radius fractures are among the most common fractures in adults, with a bimodal distribution (high-energy injuries in young adults, low-energy fragility fractures in older adults, particularly post-menopausal women). They represent roughly one in six fractures presenting to emergency departments worldwide. The shift to volar locked plating is reflected across major registries and society guidance (AAOS, BOA/BSSH, AO Foundation), driven by evidence for a lower rate of hardware- and tendon-related complications than historical dorsal plating (Rozental 2006). Importantly, high-level evidence shows that in low-demand older patients the functional advantage of plating over non-operative care is modest and time-limited - approach choice should be patient-specific, not reflexive.

Fracture Indications (Primary Use)

Absolute Indications for ORIF:

• Displaced Intra-articular Fracture: Articular step-off >2mm (post-reduction films)
• Unstable Extra-articular Fracture: Dorsal comminution, dorsal tilt >20°, radial shortening >5mm, ulnar variance >3mm positive
• Open Fractures: Gustilo I-II (volar ORIF + soft tissue coverage)
• Bilateral Fractures: Functional independence requires bilateral surgery (patient cannot use crutches/walker)

Relative Indications:

• Failed Closed Reduction: Loss of reduction in cast at 7-10 days (acceptable parameters lost)
• Patient Factors: High functional demands (professional/athletes), manual labourers (need strength restoration)
• Age and Activity: Young patients (<65) with any displacement (higher functional demands than elderly)

Fracture Patterns Suited to Volar Approach:

1. Colles Fracture (Dorsally Displaced Extra-articular)

   • Most common distal radius fracture (90%)
   • Dorsal tilt, radial shortening, impaction
   • Volar plate resists dorsal collapse (buttress effect)

2. Smith's Fracture (Volarly Displaced)

   • "Reverse Colles" - volar tilt, volar displacement
   • Volar plate directly buttresses volar fragment (ideal indication)

3. Intra-articular Patterns:

   • Die-punch fragment: Lunate facet impaction (reduces via volar, plate holds)
   • Volar Barton: Volar rim fracture with radiocarpal subluxation (direct fixation via volar)
   • 3-part/4-part: Complex intra-articular (requires articular reduction via approach or arthroscopy-assisted)

4. Chauffeur's Fracture (Radial Styloid)

   • Avulsion fracture radial styloid (scapholunate ligament insertion)
   • Volar approach provides access to styloid for ORIF

Non-Fracture Indications

Malunion Correction:

• Symptomatic distal radius malunion (loss of radial height, dorsal angulation causing DRUJ incongruity)
• Approach allows osteotomy, reduction, plate fixation

Carpal Tunnel Release:

• Can combine CTR with fracture fixation (same skin incision, extended distally into palm)
• Useful if acute carpal tunnel syndrome complicates fracture (10-15% of distal radius fractures)

Volar Plate Removal:

• Symptomatic hardware (flexor tendon irritation, prominent plate)
• Same approach for explantation

Contraindications

Absolute:

• Active Infection: Volar soft tissue infection, osteomyelitis (staged treatment required)
• Severe Open Fracture: Gustilo III with volar contamination (consider external fixation, delayed ORIF)

Relative:

• Dorsal Barton Fracture: Dorsal rim fracture (may need dorsal plate for buttress)
• Highly Comminuted Volar Cortex: No stable platform for plate (consider bridging external fixation)
• Severe Soft Tissue Injury: Volar skin loss, crush injury (wound healing concerns)
• Patient Non-compliance: Dementia, unable to follow postop precautions (consider percutaneous pinning or casting)

Clinical Assessment

Mechanism of Injury (Informs Fracture Pattern):

• Fall on outstretched hand (FOOSH): Low-energy Colles (elderly) vs high-energy comminuted (young)
• Dashboard injury: High-energy axial load (expect intra-articular involvement, carpal injuries)
• Crush injury: Open fracture risk, soft tissue damage (consider external fixation)

Physical Examination:

Inspection:

• Deformity: "Dinner fork" (Colles - dorsal angulation) vs "Garden spade" (Smith - volar angulation)
• Swelling: Severe swelling may delay surgery (compartment syndrome risk, skin blisters)
• Skin integrity: Open wounds, blisters, abrasions (infection risk, surgical timing)

Palpation:

• Tenderness: Radiocarpal joint (intra-articular), DRUJ (associated injury), scaphoid (concomitant scaphoid fracture 5%)
• Pulses: Radial artery (thrombosis rare but catastrophic - document preop)
• Distal radioulnar joint (DRUJ): Painful DRUJ suggests triangular fibrocartilage complex (TFCC) injury or distal ulna fracture

Neurovascular Examination (MANDATORY):

• Median nerve: Thumb opposition (APB), sensation index finger (carpal tunnel syndrome in 10-15% acute fractures)
• Ulnar nerve: Finger abduction (interossei), sensation small finger
• Radial nerve: Wrist/finger extension (PIN), sensation first web space (superficial radial nerve)
• Vascular: Radial pulse, ulnar pulse (Allen test if radial artery concern), capillary refill

Imaging Essentials

Radiographs (PA, Lateral, Oblique):

PA View Measurements:

• Radial Height: Normal 11-13mm (distance from radial styloid to articular surface of ulnar head)
  • Accept <5mm shortening in elderly, <2mm in young
• Radial Inclination: Normal 22-23° (angle between articular surface and perpendicular to radial shaft)
  • Accept >15° in elderly, >20° in young
• Ulnar Variance: Normal neutral to 2mm negative (ulna shorter than radius)
  • Positive variance >3mm associated with TFCC injury, DRUJ arthritis

Lateral View Measurements:

• Volar Tilt: Normal 10-12° volar (distal radius articular surface tilts volarly)
  • Colles fracture: Dorsal tilt (reverse of normal)
  • Smith fracture: Excessive volar tilt (>20°)
  • Accept neutral to 10° volar tilt in elderly, require anatomic in young
• Dorsal Comminution: Predicts instability (requires fixation vs casting)

Oblique View:

• Radial styloid fracture (chauffeur's)
• Volar/dorsal Barton fragments (rim fractures with carpal subluxation)

CT Scan (Intra-articular Fractures):

• Articular Step-off: Quantify gap/step (>2mm = surgical indication)
• Die-punch Fragment: Lunate facet impaction (central articular depression)
• Fracture Comminution: Plan fixation (may need dorsal plate if dorsal Barton, fragment-specific screws)
• DRUJ Assessment: Distal ulna fracture, sigmoid notch fracture (associated DRUJ instability)

MRI (Rarely Indicated):

• TFCC injury suspected (painful DRUJ, ulnar-sided wrist pain persists post-healing)
• Scapholunate ligament injury (widened scapholunate interval on PA X-ray - >3mm)

Surgical Planning Decision Points

Fixation Strategy:

Plate Positioning - The Watershed Line: The "watershed line" is the critical anatomical boundary for volar plate positioning:

• Definition: Proximal extent of volar distal radius where flexor tendons contact bone (approximately 2cm proximal to radiocarpal joint)
• Rule: Plate MUST be distal to watershed line (flush with volar radius surface, not proud)
• Why: Plates proximal to watershed = prominent = flexor tendon (especially FPL) irritation/rupture

Screw Length Planning:

• Distal Screws: Subchondral purchase (within 3mm of articular surface on lateral fluoro) - provides best fixation
• Length Calculation: Lateral fluoroscopy measurement minus 2mm (accounts for articular cartilage thickness)
• Avoid: Dorsal penetration (extensor tendon irritation), intra-articular penetration (arthritis)

Essential Instrumentation

Standard Orthopaedic Set:

• Scalpel (15 blade - smaller incision, better control)
• Self-retaining retractor (small Weitlaner)
• Army-Navy retractors (superficial tissue)
• Freer elevator (pronator quadratus elevation - subperiosteal)
• Electrocautery (bipolar preferred - less collateral thermal injury)

Fracture-Specific Instruments:

• Reduction Forceps: Pointed reduction clamps (reduce fracture before plating)
• K-wires: 1.2mm for provisional fixation (hold reduction during plating)
• Distractor: External fixator or manual traction (restores radial length if impacted)
• Fluoroscopy: C-arm (MANDATORY - intraop imaging for reduction, screw length, hardware position)

Volar Plate System:

• Anatomic Volar Locked Plate: Manufacturer-specific (DVR Biomet, Acu-Loc Acumed, VariAx Stryker)
  • Distal locking screws (fixed-angle or variable-angle) - 3.5mm diameter
  • Proximal cortical or locking screws - 3.5mm diameter
  • Plate benders (contour to volar radius if needed - minimal bending)
• Screwdriver: Locking (dedicated for locked screws), standard (cortical screws)
• Drill: 2.7mm drill bit (pilot hole for 3.5mm screws)
• Depth Gauge: Measure screw length (critical - avoid dorsal penetration)

Fragment-Specific Fixation (If Needed):

• Small fragment screws (2.0mm, 2.4mm headless compression screws for styloid, lunate facet)
• Additional mini-plates (radial styloid plate, lunate facet plate)

Implant Selection

Volar Locked Plate Choice:

• Standard Profile: 2.4mm thick plates (most common - Acu-Loc, DVR)
• Ultra Low-Profile: 1.8mm thick plates (higher flexor tendon irritation risk if prominent, but less bulky)
• Variable-Angle Screws: Allow screw angulation ±15° (target specific fragments - die-punch, styloid)

Screw Selection:

• Distal Screws: Locking (provide angular stability - resist dorsal collapse)
• Proximal Screws: Locking or cortical (cortical adequate if good bone quality, cheaper)
• Length: Critical decision - measure EVERY screw intraoperatively (lateral fluoro)

Graft Options (If Needed):

• Bone Void Filler: Calcium phosphate cement (Norian, Callos) for metaphyseal defects (die-punch impaction)
• Autograft: Distal radius cancellous bone (harvest from fracture fragments) or iliac crest (rare - major defects)
• Allograft: Cancellous chips (metaphyseal void filling)

Standard Positioning - Hand Table

Setup:

1. Patient Position: Supine on OR table, operative arm abducted 90° on radiolucent hand table
2. Hand Table: Radiolucent (allows fluoroscopy - AP, lateral, oblique views)
3. Arm Position: Shoulder abducted 80-90°, elbow flexed 90°, forearm supinated (volar surface up)
4. Tourniquet: Upper arm pneumatic tourniquet (inflated to 250mmHg - exsanguinate with Esmarch first)

Advantages:

• Surgeon Ergonomics: Seated position, arm at comfortable working height (avoid back strain)
• Fluoroscopy Access: C-arm easily positioned (perpendicular to forearm for lateral, parallel for AP)
• Assistant Position: Across table (provides countertraction, handles reduction clamps)

Disadvantages:

• Requires Hand Table: Not all ORs equipped (can use standard table with arm board)
• Limited Extension: Cannot extend incision above mid-forearm (hand table length limits)

Alternative Positioning - Arm Board

Setup:

1. Patient supine, arm on standard radiolucent arm board (attached to OR table side)
2. Position allows full forearm exposure (elbow to hand)
3. Less ideal for fluoroscopy (C-arm positioning more difficult)

Tourniquet Considerations

Tourniquet Use (Standard Practice):

• Advantages: Bloodless field (visualization of median nerve, radial artery), faster surgery
• Technique:
  • Upper arm pneumatic cuff
  • Exsanguinate with Esmarch bandage (elevate arm 1 minute, then wrap distal to proximal)
  • Inflate to 250mmHg (add 100mmHg to systolic BP)
  • Safe time limit: 2 hours (most distal radius ORIF under 60 minutes)
• Release Before Closure: Achieve haemostasis before tourniquet deflation (prevents postop haematoma)

No Tourniquet (Alternative):

• Used if tourniquet contraindicated (arterial disease, sickle cell, limb ischemia risk)
• Requires meticulous haemostasis with bipolar cautery
• Median nerve and radial artery more difficult to identify (not exsanguinated)

Surface Landmarks

Palpable Structures (Mark Preoperatively):

1. Radial Styloid: Most distal radial prominence (lateral wrist) - palpable
2. FCR Tendon: Palpate at wrist crease - most prominent flexor tendon on radial side (ask patient to flex wrist against resistance)
3. Radial Artery Pulse: Lateral to FCR tendon (palpate between FCR and brachioradialis)
4. Distal Wrist Crease: Approximate level of radiocarpal joint

Incision Planning:

• Start: 1cm proximal to distal wrist crease (avoid crease itself - hypertrophic scar)
• Direction: Longitudinal along FCR tendon (radial border of volar forearm)
• Length: 8-10cm (allows exposure from mid-pronator quadratus to proximal radius metaphysis)
• Endpoint: Distal end at radial styloid level (can extend into palm if CTR needed)

Anatomic Intervals and Structures

The FCR Interval:

• Radial Border: FCR tendon (flexor carpi radialis - inserts at base of 2nd metacarpal)
• Lateral Structure: Radial artery (runs between FCR and brachioradialis in forearm)
• Medial Structure: Median nerve (deep to flexor digitorum superficialis at wrist level)

Key Point: This is NOT an internervous plane - it's a tendon-artery interval. The FCR is innervated by the median nerve, and the brachioradialis (lateral) is innervated by the radial nerve, but you're NOT dissecting between these muscles - you're working between the FCR tendon and the radial artery.

Critical Neurovascular Anatomy

Palmar Cutaneous Branch of Median Nerve (PCB):

• Course: Arises from the radial/volar aspect of the median nerve approximately 5-7cm proximal to the wrist crease, travels distally in the subcutaneous plane (superficial to the flexor retinaculum) toward the thenar skin
• Position: Lies close to the FCR, typically just ulnar to it - on average only 3.4mm from the FCR tendon at the watershed level (McCann cadaveric study), making it the structure at highest anatomic risk in this approach
• Innervation: Sensory to the skin over the thenar eminence and thenar/proximal palm
• Injury Consequences: Painful neuroma if divided, sensory loss over the thenar eminence, scar/pillar hypersensitivity

Median Nerve (Main Trunk):

• Position: Medial (ulnar) to FCR tendon at wrist level - on average ~8.9mm from the FCR tendon (McCann cadaveric study)
• Course: Deep to flexor digitorum superficialis (FDS), enters carpal tunnel at wrist
• At Risk: If retraction too aggressive medially (traction injury), during pronator quadratus elevation if dissect too far ulnar
• Protection: Gentle medial retraction, stay on radial side of pronator quadratus

Radial Artery:

• Position: Lateral (radial) to FCR tendon (between FCR and brachioradialis in forearm, between FCR and radial styloid at wrist)
• Course: Runs on volar surface of pronator quadratus distally, winds around radial styloid into anatomic snuffbox
• At Risk: During FCR sheath opening (may be adherent to radial border of sheath), fracture manipulation (spasm/thrombosis rare <1%)
• Palpate: Throughout case (ensure pulse present - if lost, assess for kinking, spasm, thrombosis)

Anterior Interosseous Nerve (AIN):

• Position: Deep on interosseous membrane (between radius and ulna)
• Course: Travels distally with anterior interosseous artery, innervates pronator quadratus (motor), distal radius periosteum (sensory)
• At Risk: During pronator quadratus elevation (nerve on deep surface), fracture manipulation
• Function: Motor to FPL, FDP to index, pronator quadratus (not testable intraop - patient asleep)

Flexor Tendon Anatomy

Flexor Pollicis Longus (FPL):

• Position: Most radial flexor tendon (crosses distal radius at watershed line level)
• At Risk: Screw penetration dorsal cortex (screw tips contact FPL), plate prominence proximal to watershed (plate-tendon friction = rupture)
• Protection: Measure screw length accurately (lateral fluoro - subtract 2mm), ensure plate distal to watershed

Flexor Carpi Radialis (FCR):

• Sheath: Tendon runs in fibro-osseous tunnel (FCR groove on volar radius - trapezium distally)
• Surgical Use: FCR sheath is opened (tendon retracted ulnar) to access radius
• Repair: FCR sheath usually NOT repaired (no functional consequence)

Pronator Quadratus Muscle

Anatomy:

• Origin: Distal ulna volar surface (distal 25% of ulna)
• Insertion: Distal radius volar surface (distal 25% of radius)
• Fibers: Horizontal (deepest forearm muscle - directly overlies volar distal radius)
• Innervation: Anterior interosseous nerve (AIN) - branch of median nerve

Surgical Importance:

1. Covers Volar Radius: Must elevate pronator quadratus to expose fracture/distal radius
2. Plate Coverage: Repair of pronator quadratus over the plate provides a soft-tissue barrier between the implant and the flexor tendons (theoretical protection; not shown to change functional outcome in meta-analysis - Shi 2020)
3. Blood Supply to Distal Radius: Pronator quadratus has rich vascular supply (healing benefit if preserved)

Elevation Technique:

• L-shaped Flap: Incise pronator along radial insertion (vertical limb), extend ulnar along distal border (horizontal limb)
• Subperiosteal: Elevate muscle off radius as flap (preserves muscle, allows anatomic repair)
• Preserve Ulnar Insertion: Keeps muscle viable (blood supply from ulnar side)

Step 1: Skin Incision and Superficial Dissection

Incision:

• Start Point: 8-10cm proximal to wrist crease (mid-volar forearm)
• Direction: Longitudinal along FCR tendon (palpate tendon, mark with skin marker)
• Length: 8-10cm (allows exposure of distal radius from metaphysis to radiocarpal joint)
• End Point: Distal end at radial styloid level (or extend into palm if CTR needed)

Avoid Wrist Crease: Do NOT make incision directly in wrist crease (hypertrophic scarring, wound breakdown risk). Stay 1-2cm proximal to crease.

Skin Dissection:

• 15 blade scalpel, incise dermis
• Deepen through subcutaneous fat (3-5mm depth)
• Identify superficial veins (ligate or cauterize with bipolar)

Protect the Palmar Cutaneous Branch (CRITICAL STEP): The PCB runs in the subcutaneous plane very close to the FCR (on average ~3.4mm ulnar to it - McCann). Rather than relying on seeing a 1-2mm nerve, protect it by technique:

• Keep the skin incision and deep dissection over/just radial to the FCR tendon
• Open the FCR sheath and work through its floor, retracting FCR ulnarward (this carries the FCR - and the adjacent PCB - away from the operative field)
• Avoid wide blunt subcutaneous undermining toward the ulnar/palmaris side
• If the nerve is seen: protect it with a vessel loop and gentle retraction throughout the case (do NOT divide)

Step 2: Identify and Open FCR Tendon Sheath

Palpate FCR Tendon:

• Most prominent radial-sided flexor tendon at wrist
• Firm white cord (visible through deep fascia once subcutaneous tissue divided)
• Distal to proximal: Tendon enters FCR groove (trapezium), then runs in sheath on radius

Palpate Radial Artery:

• Lateral to FCR (between FCR and brachioradialis distally)
• Pulsatile (if tourniquet not inflated) or cord-like (if exsanguinated)
• Mark position mentally (MUST protect throughout case)

Open FCR Sheath:

1. Identify sheath (thin white fascial layer overlying FCR tendon)
2. Incise sheath longitudinally (15 blade - parallel to tendon fibers)
3. Open sheath from wrist crease (distal) to 8cm proximally
4. Reflect sheath edges (FCR tendon now visible in base of wound)

Retract FCR Tendon:

• Place small Army-Navy or Senn retractor ULNAR to FCR (retracts FCR medially)
• Radial artery retracts LATERALLY with brachioradialis (stays protected lateral)
• You've now created the interval: Radial artery (lateral), FCR tendon (medial/ulnar)

Step 3: Expose Pronator Quadratus

Identify Pronator Quadratus:

• Deepest structure in wound (after FCR retracted ulnar, radial artery retracted radial)
• Horizontal muscle fibers (perpendicular to forearm long axis)
• Covers entire volar distal radius surface

Palpate Fracture Through Pronator:

• Dorsal displacement palpable (Colles - dorsal step in bone under muscle)
• Radial shortening palpable (fracture fragments may be impacted)
• Swelling/haematoma within pronator muscle (fracture haematoma)

Step 4: Elevate Pronator Quadratus (L-Shaped Flap)

Incision Design:

1. Vertical Limb: Incise pronator along radial insertion (where muscle inserts on radius radial border)

   • Start at radial styloid (distal), extend 6-8cm proximally
   • Stay on muscle insertion (elevate muscle off bone subperiosteally)

2. Horizontal Limb: At proximal extent of vertical incision, turn 90° ulnar

   • Incise along distal border of pronator (just proximal to radiocarpal joint)
   • Extend ulnar 2-3cm (creates L-shaped flap)

Elevate Flap:

• Freer elevator (or periosteal elevator) - subperiosteal dissection
• Elevate pronator quadratus OFF radius (from radial to ulnar direction)
• Muscle elevates as flap (ulnar insertion intact - preserves blood supply)
• Reflect flap ulnar (exposes entire volar distal radius surface)

What You See:

• Volar distal radius cortex (bone surface)
• Fracture line(s) visible
• Haematoma (evacuate with suction)
• Assess fracture pattern (extra-articular vs intra-articular, comminution)

Step 5: Fracture Reduction

Reduction Maneuvers:

Extra-articular Fractures (Colles):

1. Restore Radial Length: Apply longitudinal traction (assistant pulls on thumb, surgeon grasps proximal fragment)

   • Disimpact fracture (dorsal cortex usually impacted)
   • Consider external distractor if severe impaction (rare - manual traction usually sufficient)

2. Correct Dorsal Tilt: Volar translation of distal fragment (push volar from dorsal)

   • Dorsally displaced fragment needs volar translation + flexion force
   • Palpate dorsal cortex (ensure reduced - should feel flush)

3. Provisional Fixation: K-wires (1.2mm) from radial styloid into proximal fragment

   • 2-3 K-wires hold reduction while applying plate
   • Check fluoroscopy (AP and lateral - confirm acceptable reduction)

Intra-articular Fractures:

1. Identify Articular Fragments: Die-punch (lunate facet impaction), radial styloid, volar/dorsal rim
2. Reduce Articular Surface:
   • Elevate die-punch fragment (Freer elevator through fracture site)
   • Reduce styloid fragment (clamp to shaft with pointed reduction forceps)
   • Bone graft/void filler if metaphyseal defect (die-punch creates void when elevated)
3. Provisional Fixation: K-wires hold fragments reduced
4. Fluoroscopy: Confirm articular step <2mm (AP, lateral, oblique views)

Reduction Goals (Fluoroscopy Confirmation):

• AP View: Radial height restored (11-13mm), radial inclination >20°, no articular step
• Lateral View: Volar tilt 0-10° (neutral to slight volar), no dorsal angulation, articular surface congruent

Step 6: Plate Application

Plate Selection:

• Anatomic volar locked plate (sized to distal radius - small, standard, large based on patient size)
• Most adults: Standard plate (covers volar radius without overhang)

Plate Positioning (CRITICAL):

Distal-Proximal Position:

• Plate should sit JUST PROXIMAL to watershed line (2cm proximal to radiocarpal joint)
• Distal edge of plate at pronator quadratus distal insertion level
• Too distal: Plate extends onto volar rim (intra-articular, blocks wrist flexion)
• Too proximal: Plate proud of watershed line (flexor tendon irritation)

Radial-Ulnar Position:

• Plate centered on volar radius (avoid radial or ulnar overhang)
• Radial edge of plate at junction of radial styloid and volar shaft

Plate Contouring:

• Minimal bending (plates are pre-contoured to volar radius anatomy)
• If needed: Gentle bending with plate benders (avoid sharp angles - stress risers)

Provisional Plate Fixation:

1. Place plate on volar radius (position as above)
2. Insert 1-2 proximal NON-locking screws (cortical screws) - do NOT lock yet
   • Screws in oblong holes (allow plate to slide distally if needed)
3. Fluoroscopy (AP and lateral): Confirm plate position, check distal screw trajectories

Adjust Plate:

• If distal screws will penetrate dorsal cortex OR enter radiocarpal joint: Reposition plate (usually move proximal 2-3mm)

Step 7: Distal Screw Insertion (Most Critical Step)

Distal Screw Principles:

• Goal: Subchondral purchase (screws within 3mm of articular surface - provides best fixation)
• Fixed-Angle: Locking screws (prevent toggling, resist dorsal collapse)
• Length: CRITICAL - must check EACH screw intraoperatively

Distal Screw Insertion Technique:

1. Drill Distal Holes: 2.7mm drill bit through locking holes (drill guide ensures correct angle)

   • Lateral fluoroscopy: Confirm drill bit trajectory (parallel to articular surface, subchondral depth)
   • Drill until dorsal cortex (feel breakthrough, watch fluoro)

2. Measure Screw Length:

   • Depth gauge through drill hole (measures to dorsal cortex)
   • SUBTRACT 2mm from measurement (accounts for articular cartilage thickness - prevents intra-articular penetration)
   • Example: Depth gauge reads 18mm → Use 16mm screw

3. Insert Locking Screws:

   • Self-tapping locking screws (or tap first if non-self-tapping)
   • Insert 3-4 distal screws (depends on plate - usually 2 rows, 4-6 screws total)
   • Screw heads lock into plate (fixed angle - cannot toggle)

4. Check EVERY Screw (Fluoroscopy):

   • Lateral View: Screws should not penetrate the dorsal cortex (dorsal screw prominence risks extensor tendon irritation/rupture)
   • Dorsal Tangential ("skyline") View: Critical adjunct - the dorsal cortex of the distal radius is undulating (Lister's tubercle, dorsal ridges), so a screw that looks contained on a true lateral can still be dorsally prominent. The skyline view (forearm vertical, wrist flexed, beam tangential to the dorsal cortex) reliably detects this and is the most sensitive view for dorsal screw penetration
   • AP View: Screws within bone (not exiting radially or ulnarly), not crossing the radiocarpal or DRUJ articulations
   • If Screw Long: Remove, measure again, insert shorter screw

Step 8: Proximal Screw Insertion

Proximal Fixation:

• Goal: Secure plate to radial shaft (prevents toggling, transfers load)
• Screw Type: Locking or non-locking (cortical screws adequate if good bone quality)

Technique:

1. Drill proximal holes (2.7mm drill bit)
2. Measure screw length (depth gauge - bicortical purchase ideal)
3. Insert 3-4 proximal screws (locking or cortical)
4. Tighten proximal screws (final plate position fixed)

Remove K-wires:

• Provisional K-wires removed (plate now provides definitive fixation)

Step 9: Final Fluoroscopy Check

Systematic Fluoroscopy Protocol:

AP View:

• Radial height restored (11-13mm normal)
• Radial inclination >20°
• No articular step-off (gap <2mm)
• Screws within bone (no radial/ulnar overhang)
• Ulnar variance neutral to 2mm negative

Lateral View:

• Volar tilt 0-10° (neutral to slight volar)
• NO screw penetration dorsal cortex (screws 2-3mm from dorsal surface)
• Plate proximal to radiocarpal joint (not blocking wrist flexion)
• Articular congruity maintained

Oblique View:

• Radial styloid fragment reduced (if fractured)
• Screw position acceptable (no joint penetration)

Range of Motion:

• Release tourniquet (assess reperfusion)
• Passive wrist flexion/extension (ensure no block - plate not impinging)
• Finger flexion/extension (ensure no tendon injury - FPL, FDP move freely)

Step 10: Closure and Pronator Quadratus Repair

Pronator Quadratus Repair (Reasonable Coverage - Not Evidence-Mandated):

Why Repair Pronator?

• Aims to restore a soft-tissue layer between the plate and the flexor tendons
• May contribute vascular supply to the distal radius
• Evidence caveat: meta-analyses (Shi 2020; Lu 2020) found NO significant difference in DASH, grip strength or ROM with vs without repair - so it is a reasonable, low-cost step for coverage but should not be claimed to improve function or to halve complications

Repair Technique:

Option 1: Side-to-Side Repair (Preferred)

1. Pronator quadratus flap reflected ulnar (radial insertion detached, ulnar insertion intact)
2. Re-approximate radial insertion to radius periosteum
3. 2-0 or 3-0 Vicryl sutures (mattress or simple interrupted)
4. 4-6 sutures along radial border (reattach muscle to insertion site)

Option 2: Transosseous Repair

1. Drill small holes (2mm) in distal radius (lateral edge)
2. Pass sutures through bone holes, then through pronator muscle edge
3. Tie sutures (muscle apposed to bone)

If Pronator Cannot Reach:

• Severe comminution or tissue loss may prevent tension-free repair
• Accept partial coverage (better than no coverage)
• Consider brachioradialis turndown flap (advanced technique - rarely needed)

Fascial Closure:

• FCR sheath: Usually not repaired (no functional benefit)
• Deep fascia (over pronator): 3-0 Vicryl interrupted (loose approximation)

Subcutaneous Closure:

• 3-0 Vicryl interrupted sutures (invert skin edges)
• Ensure haemostasis (meticulous - wrist haematomas are common)

Skin Closure:

• 4-0 Monocryl subcuticular running suture (excellent cosmesis)
• Dermabond or Steri-Strips (skin adhesive)

Dressing:

• Sterile gauze, cotton padding (circumferential but not compressive)
• Volar splint (wrist neutral, forearm neutral rotation, fingers free to PIP joints)
• Elevate hand postop (reduce swelling)

Pre-Closure Verification

Fluoroscopy Final Check:

• AP: Radial height, inclination, no articular step, screws within bone
• Lateral: Volar tilt 0-10°, NO dorsal screw penetration, plate position acceptable
• Oblique: Fragment reduction adequate

Hardware Position:

• Plate distal to watershed line (will not irritate FPL)
• All screws measured and checked (no dorsal penetration)
• No screws intra-articular (lateral view confirms)

Haemostasis:

• Tourniquet deflated, bleeding controlled (cauterize vessels)
• Radial artery pulse present (confirm perfusion)
• No active bleeding from fracture site or soft tissue

Range of Motion:

• Passive wrist flexion/extension (no block from hardware)
• Finger flexion/extension (FPL, FDP intact - no resistance)

Layer-by-Layer Closure

Deep Layers:

1. Pronator Quadratus Repair: 2-0 Vicryl × 4-6 sutures (side-to-side to radial periosteum)
2. Deep Fascia: 3-0 Vicryl × 3-4 interrupted (loose approximation over pronator)

Superficial Layers: 3. Subcutaneous: 3-0 Vicryl × 6-8 interrupted (invert edges, meticulous haemostasis) 4. Skin: 4-0 Monocryl subcuticular running, Dermabond

Splint Application:

• Volar plaster splint (forearm-based, wrist neutral)
• Fingers free to PIP joints (allows digit ROM - prevents stiffness)
• Thumb IP joint free (allows thumb motion)
• Splint extends to proximal palmar crease (allows full finger flexion)

Intraoperative Complications

Palmar Cutaneous Nerve Injury (structure at highest anatomic risk - ~3.4mm from FCR, McCann)

• Mechanism: Divided or stretched during subcutaneous dissection, or caught by aggressive ulnar-side retraction
• Presentation: Cannot be tested intraoperatively (patient asleep); postoperatively a painful thenar eminence and scar hypersensitivity
• Management:
  • If recognized intraop (nerve cut): primary repair (microsurgical - 8-0 nylon, nerve ends approximated)
  • If recognized postop: observation 3-6 months (many improve), and if persistent painful neuroma = excision + nerve burial
• Prevention: technique-based - work through the FCR sheath, retract FCR ulnarward, keep deep dissection radial, avoid wide ulnar-side subcutaneous undermining; vessel loop if the nerve is seen

Radial Artery Injury (<1%)

• Mechanism: Laceration during FCR sheath opening (artery adherent to sheath), fracture manipulation (spasm)
• Presentation: Loss of radial pulse, bleeding (if laceration)
• Management:
  • Spasm: Warm saline, topical papaverine (usually resolves)
  • Laceration: Vascular repair (primary vs vein graft) - consult vascular if available
  • Ligation: Acceptable IF ulnar artery intact (check Allen test preop - documented), but preferably repair
• Prevention: Identify radial artery before FCR sheath opening, palpate throughout case

Median Nerve Injury (<1%)

• Mechanism: Traction (aggressive medial retraction), direct trauma (dissection too far ulnar)
• Presentation: Postop thenar weakness (APB), numbness median distribution
• Management: Usually neuropraxia (observation, recovery 3-6 months), EMG at 6 weeks if no improvement
• Prevention: Gentle medial retraction, stay on radial side of pronator quadratus

Flexor Pollicis Longus Tendon Injury

• Mechanism: Screw dorsal penetration (drill bit or screw perforates dorsal cortex, enters FPL)
• Presentation: Cannot test intraop, postop weak/absent thumb IP flexion
• Management: Revision surgery (remove offending screw, repair tendon if lacerated)
• Prevention: Lateral fluoroscopy check of EVERY screw before proceeding

Loss of Reduction During Fixation

• Mechanism: Provisional K-wires lose purchase, fracture collapses during plating
• Presentation: Fluoroscopy shows dorsal tilt recurrence or articular step
• Management: Remove plate, re-reduce fracture, consider bone graft (if metaphyseal void), re-plate
• Prevention: Adequate provisional fixation (2-3 K-wires), check reduction before drilling distal holes

Early Postoperative Complications (0-6 weeks)

Carpal Tunnel Syndrome (10-15% transient)

• Mechanism: Median nerve compression (postop swelling, haematoma, fracture displacement pre-reduction)
• Presentation: Numbness median distribution (thumb, index, middle fingers), weak thumb opposition
• Natural History: Most resolve with swelling reduction (2-6 weeks), elevation, splint removal
• Management:
  • Transient (improving): Observation, elevate hand, remove splint at 2 weeks
  • Persistent (>6 weeks) or severe: Carpal tunnel release (decompress median nerve)
• Prevention: Adequate fracture reduction (relieves median nerve pressure), elevate hand postop

Infection (1-2%)

• Presentation: Wound erythema, drainage, pain, fevers (usually 7-14 days postop)
• Organisms: Staph aureus (80%), Strep species
• Diagnosis: Wound culture, blood cultures if systemic signs, CRP/ESR
• Management (follow local microbiology/antimicrobial guidance for agent and dose):
  • Superficial (skin/subcutaneous): oral anti-staphylococcal antibiotics, wound care
  • Deep (plate contaminated): surgical debridement with plate retention if the fixation is stable and the fracture is unhealed, plus IV antibiotics; remove hardware once the fracture has united if infection persists
  • Severe (osteomyelitis, loose plate): explant plate, debride, stabilise (e.g. external fixation), delayed re-fixation
• Prevention: prophylactic IV antibiotic at induction (typically a first-generation cephalosporin per local protocol), meticulous haemostasis, gentle tissue handling

Compartment Syndrome (Rare <1%)

• Mechanism: Volar forearm compartment pressure (haematoma, fracture displacement, tight splint/cast)
• Presentation: Pain out of proportion (especially with passive finger extension), tense forearm, paresthesias
• Diagnosis: Clinical (high suspicion), compartment pressure measurement if uncertain (>30mmHg = compartment syndrome)
• Management: EMERGENCY fasciotomy (release volar and dorsal forearm compartments)
• Prevention: Elevate hand postop, loose splint (not circumferential cast immediately postop), educate patient (return if severe pain)

Late Postoperative Complications (>6 weeks)

Flexor Tendon Irritation/Rupture (2-5%)

• Mechanism: Plate prominence (proximal to watershed line), screw dorsal penetration (FPL contact)
• Presentation:
  • Irritation: Painful wrist flexion, triggering sensation (FPL catching on plate)
  • Rupture: Sudden loss of thumb IP flexion (FPL rupture - usually 3-12 months postop)
• Diagnosis: Clinical (inability to flex thumb IP joint), ultrasound (tendon discontinuity)
• Management:
  • Irritation: Plate removal (if >6 months postfracture - bone healed)
  • Rupture: Tendon reconstruction (FPL tendon transfer - use palmaris longus graft, FDS ring finger transfer)
• Prevention: Plate distal to watershed line, pronator quadratus repair, screw length checks

Malunion (5-10%)

• Mechanism: Loss of reduction (inadequate fixation, osteoporotic bone), non-compliance (early splint removal)
• Presentation: Dorsal angulation (Colles deformity recurrence), radial shortening, ulnar-sided wrist pain (DRUJ incongruity)
• Diagnosis: X-ray (lateral shows dorsal tilt, AP shows radial shortening, ulnar variance)
• Management:
  • Symptomatic + under 6 months: Corrective osteotomy (re-cut, re-reduce, re-plate ± bone graft)
  • Asymptomatic: Observation (many elderly patients tolerate mild malunion)
• Prevention: Adequate fixation (locked distal screws, bone graft if metaphyseal void), splint compliance 6 weeks

Stiffness (10-20%)

• Presentation: Limited wrist ROM (especially extension - normal 60-70°, stiffness may be 20-30°)
• Risk Factors: Prolonged immobilization (>6 weeks), intra-articular fractures, elderly patients
• Prevention: Early ROM exercises (begin 2 weeks postop - gentle PROM, progress to AROM at 6 weeks)
• Management:
  • Under 6 months: Intensive physiotherapy (3× per week, static progressive splinting)
  • >6 months: Manipulation under anaesthesia (rarely needed for distal radius - arthrofibrosis uncommon)

Complex Regional Pain Syndrome (CRPS) (5-10%)

• Presentation: Severe pain, swelling, skin color changes (red/blue), temperature changes (hot/cold), hypersensitivity
• Diagnosis: Clinical (Budapest criteria - pain disproportionate to injury, vasomotor/sudomotor/motor changes)
• Management:
  • Early mobilization (CRITICAL - prevents CRPS progression)
  • PT (desensitization, mirror therapy, graded motor imagery)
  • Medications (gabapentin, amitriptyline for neuropathic pain)
  • Stellate ganglion block (if refractory - anesthesia pain clinic)
• Prevention: Adequate analgesia, early mobilization, avoid prolonged immobilization

Immediate Postoperative Care (Day 0-1)

Recovery Room:

• Neurovascular check (median nerve function, radial pulse - document)
• Pain control: Regional block (brachial plexus at axilla or forearm level), oral opioids (oxycodone 5mg PRN)
• X-ray (AP and lateral wrist - confirm hardware position unchanged, no intraop loss of reduction)

Ward Care:

• Hand elevation (above heart level - reduces swelling, prevents haematoma)
• Cryotherapy (ice packs 20 min Q2h - reduces swelling, improves pain)
• Digit ROM (immediate finger/thumb flexion-extension - prevents stiffness, CRPS)

Discharge Criteria (Same Day or Day 1):

• Pain controlled (NRS under 4/10 on oral meds)
• Neurovascularly intact (median nerve, radial pulse documented)
• Safe mobilization (sling not required - hand in splint, patient independent)
• Understands splint care (keep dry, elevate, finger ROM exercises)

Outpatient Follow-up Protocol

Week 2:

• Wound Check: Remove dressing, assess for infection (erythema, drainage)
• Suture Removal: If non-absorbable (most use absorbable - no removal needed)
• Splint: Continue volar splint (wrist neutral, fingers free)
• X-ray: AP and lateral wrist (assess hardware position, early healing)
• Physiotherapy: Finger/thumb ROM (full flexion-extension), gentle wrist PROM (PT-assisted if stiff)

Week 6:

• X-ray: AP, lateral, oblique (assess fracture healing - bridging callus expected)
• Clinical Exam: ROM (PROM vs AROM), tenderness, grip strength
• Splint Removal: Discontinue splint (fracture stable with plate, bone healing progressing)
• Physiotherapy Progression:
  • Active wrist ROM (AROM - flexion, extension, radial/ulnar deviation)
  • Light resistance (Theraband, putty exercises)
  • Avoid heavy lifting >2kg (bone still healing)

Week 12:

• X-ray: Confirm union (cortical bridging on 3/4 cortices)
• ROM Goals: Flexion 60-70° (80% contralateral), extension 50-60° (80% contralateral)
• Strength Testing: Grip strength 50-70% of contralateral (Jamar dynamometer)
• Return to Activity: Unrestricted ADLs, light work (no heavy labour yet)

Month 6:

• Final X-ray: Confirm mature union, assess for hardware complications (loosening rare)
• ROM: Should be 80-90% of contralateral wrist (near-normal function)
• Return to Full Activity: Manual labour, contact sports OK (fracture healed, plate provides long-term support)
• Hardware Removal: Consider if symptomatic (flexor tendon irritation, plate prominence) - remove >12 months postop (bone remodeling complete)

Physiotherapy Protocol

Phase 1 (Weeks 0-2): Protection + Digit Mobilization

• Goals: Prevent finger stiffness, reduce swelling
• Exercises:
  • Finger flexion-extension (make full fist, then fully extend - 10 reps Q2h)
  • Thumb opposition (touch thumb to each fingertip - prevents CMC stiffness)
  • Elevation (hand above heart - gravity drainage of edema)
• Restrictions: Wrist immobilized in splint (no wrist ROM), no lifting

Phase 2 (Weeks 2-6): Gentle Wrist PROM

• Goals: Prevent wrist stiffness, maintain fracture reduction
• Exercises:
  • Passive wrist flexion-extension (PT-assisted or opposite hand - gentle ROM)
  • Forearm rotation (pronation-supination - elbow at side, 90° flexed)
  • Edema control (retrograde massage, compression glove if persistent swelling)
• Restrictions: NO active wrist ROM (bone healing 3-6 weeks - avoid loads on fracture), NO lifting

Phase 3 (Weeks 6-12): Active ROM + Light Strengthening

• Goals: Restore active wrist ROM, begin strengthening
• Exercises:
  • Active wrist flexion-extension (no weight - gravity resistance only)
  • Wrist radial-ulnar deviation (active ROM)
  • Theraband resistance (light - wrist flexion/extension against band)
  • Grip strengthening (putty, sponge squeeze - light resistance)
• Restrictions: Avoid heavy lifting >2kg

Phase 4 (Months 3-6): Return to Function

• Goals: Full ROM, near-normal strength
• Exercises: Progressive resistance (weights 2-5kg), functional activities (lifting, carrying)
• Return to Work: Sedentary 6 weeks, light duty 3 months, heavy labour 6 months

Return to Function and Documentation

Hand Therapy Access: Supervised hand therapy improves outcomes and should be arranged early; funding pathways differ by health system (public, private insurance, statutory/workers-compensation schemes). The clinical principle is consistent worldwide - early supervised digit and forearm mobilisation, then graded wrist ROM and strengthening.

Return to Work (guide - individualise):

• Sedentary: 6-8 weeks (office work, keyboard use)
• Light Manual: ~3 months (occasional lifting under 5kg)
• Heavy Manual: ~6 months (repetitive lifting, manual labour)

Driving (counsel preoperatively, follow local licensing rules):

• Dominant/steering-side wrist: typically not safe until out of splint with adequate grip and control (around 6 weeks)
• Non-dominant wrist (automatic transmission): often earlier (2-4 weeks)
• Patients are responsible for safe vehicle control; advise arranging transport for the early period

Documentation: Record median nerve function before and after surgery. If acute carpal tunnel syndrome is present preoperatively, document it clearly; if it develops postoperatively, distinguish a surgical (iatrogenic) cause from fracture/haematoma-related compression.