import { OnePagerSummary, ContentSection, ExamWarning, InfoCardGrid, InfoCard, EvidenceCard, ComparisonTable, VivaScenario, MnemonicCard, ExamCheatSheet, ExamPearl, Tab, Tabs } from '@/components/mdx' The **Henry approach** is the STANDARD anterolateral (volar) approach to the **entire length of the radius** from the **proximal 1/3 to the distal metaphysis** (Henry 1945). It is the MOST VERSATILE radius approach, providing EXTENSILE exposure for radial shaft fractures, nonunion, malunion, and forearm pathology. ### Internervous Plane The Henry approach utilizes a **TRUE internervous plane** that VARIES by location along the radius: **Proximal 1/3 Radius (Elbow to Proximal Shaft):** - **Interval**: Between **brachioradialis** (radial nerve) laterally and **pronator teres** (median nerve) medially - **Deep dissection**: Requires **supinator muscle splitting** to expose proximal radial shaft (PIN on deep surface of supinator - AT RISK) - **PIN location**: 2-5cm distal to radial head, on deep surface of supinator (Spinner 1968) **Middle 1/3 Radius (Mid-Shaft):** - **Interval**: Between **brachioradialis** (radial nerve) laterally and **flexor carpi radialis (FCR)** (median nerve) medially - **Critical structure**: **Radial artery** lies BETWEEN brachioradialis and FCR in this region (PRIMARY vascular hazard - Leversedge 2008) - **Deep plane**: Direct exposure of radius periosteum after mobilizing radial artery medially with FPL **Distal 1/3 Radius (Distal Shaft to Metaphysis):** - **Interval**: Between **FCR** (median nerve) medially and **brachioradialis tendon** laterally - **Critical nerve**: **Superficial radial nerve** emerges from under brachioradialis 6-9cm proximal to radial styloid - MOST INJURED nerve structure (5-10% sensory dysesthesia - Ring 2004) - **Deep plane**: Between **pronator quadratus** (covers distal radius volar surface) and radius periosteum ### Critical Neurovascular Structures **1. RADIAL ARTERY (PRIMARY VASCULAR HAZARD):** - **Course**: Lies **between brachioradialis and FCR** in middle/distal radius (medial to brachioradialis throughout) - **Surgical strategy**: Identify artery in PROXIMAL wound, mobilize MEDIALLY with FPL and median nerve (safer than lateral retraction) - **Injury risk**: 0.5-1% iatrogenic injury during Henry approach (Leversedge 2008) - **Clinical pearl**: Radial artery pulsation is the LANDMARK for identifying the internervous plane **2. SUPERFICIAL RADIAL NERVE (MOST INJURED NERVE):** - **Course**: Runs DEEP to brachioradialis in proximal/middle forearm, emerges 6-9cm proximal to radial styloid, crosses surgical field to dorsum of hand - **Surgical strategy**: Identify nerve under distal brachioradialis, protect with MEDIAL retraction (avoid stretching or compression) - **Injury risk**: 5-10% sensory dysesthesia (transient 10%, permanent 2% - Ring 2004) - **Clinical manifestation**: Painful neuroma, dysesthesia over dorsal thumb/index finger web space **3. POSTERIOR INTEROSSEOUS NERVE (PIN):** - **At risk ONLY in proximal 1/3 dissection**: PIN lies on deep surface of supinator 2-5cm distal to radial head - **Surgical strategy**: Split supinator in LINE OF ITS FIBERS with forearm in FULL SUPINATION (PIN migrates anteriorly with supination - increases safety clearance - Stern 1984) - **Injury risk**: 2-5% transient PIN palsy with proximal dissection (Spinner 1968) - **Clinical manifestation**: Finger/thumb extension weakness (EPL, EDC, EIP), wrist drop if radial nerve involved **4. LATERAL ANTEBRACHIAL CUTANEOUS NERVE (LABC):** - **Course**: Terminal branch of musculocutaneous nerve, emerges lateral to biceps tendon, crosses volar forearm - **Surgical strategy**: Protect with lateral skin flap retraction (avoid electrocautery near subcutaneous tissue) - **Injury risk**: 2-3% sensory dysesthesia over lateral volar forearm (usually transient) **5. MEDIAN NERVE:** - **Course**: Lies MEDIAL to brachial artery in antecubital fossa, passes between two heads of pronator teres, gives off AIN 4-6cm distal to lateral epicondyle - **Surgical strategy**: Usually NOT visualized (lies medial to surgical field), mobilize radial artery medially to avoid medial dissection - **Injury risk**: Less than 0.5% (median nerve rarely injured in standard Henry approach) **Most vulnerable vascular structure**: The radial artery is the SINGLE MOST VULNERABLE structure during Henry approach (0.5-1% iatrogenic injury rate - Leversedge 2008). The artery lies BETWEEN brachioradialis (lateral) and FCR (medial) in the middle/distal radius - NOT in the internervous plane itself. **Surgical strategy**: (1) Identify radial artery pulsation as LANDMARK for internervous plane. (2) Incise fascia LATERAL to artery (between BR and artery). (3) Mobilize artery MEDIALLY with FPL and median nerve using BLUNT dissection. (4) Avoid LATERAL retraction of artery (increases tension and injury risk). (5) Control artery with vessel loops if high-risk dissection. **If injured**: Immediate vascular surgery consultation for primary repair or reverse interposition graft. **Most common complication**: The superficial radial nerve (SRN) is the MOST COMMONLY INJURED nerve structure during Henry approach (5-10% sensory dysesthesia, 2% permanent - Ring 2004). The SRN emerges from under brachioradialis 6-9cm proximal to radial styloid and crosses the surgical field to reach the dorsum of the hand. **Prevention**: (1) Identify SRN exiting from under distal brachioradialis tendon. (2) Protect with GENTLE MEDIAL retraction (avoid stretching). (3) Avoid electrocautery near SRN. (4) Minimize retraction time. **Clinical manifestation**: Painful neuroma, dysesthesia over dorsal thumb/index finger web space (SRN distribution). Most resolve spontaneously by 3-6 months. Persistent neuroma may require neuroma excision or nerve transfer. ### Patient Positioning **Setup:** - **Supine** position on operating table - **Arm abducted 90° on arm board** (standard upper extremity positioning) - **Forearm supinated** (palm up) for most of dissection (except proximal 1/3 where supination protects PIN) - **Tourniquet** on upper arm (250-280mmHg for 90-120 minutes) - **Fluoroscopy** (C-arm) available for intraoperative reduction/fixation verification ### Incision Planning **Skin Incision:** - **Proximal extent**: 2-3cm distal to antecubital fossa (to avoid crossing elbow crease) - **Distal extent**: To within 4-5cm of radial styloid (to avoid SRN injury with excessive distal dissection) - **Course**: Follows the **mobile wad** (brachioradialis muscle belly) in proximal/middle forearm - **Distal course**: Curves RADIALLY toward FCR tendon (staying lateral to FCR) to reach distal radius **Incision Landmarks:** - **Proximal**: Lateral to biceps tendon in antecubital fossa - **Middle**: Over brachioradialis muscle belly (easily palpable with wrist extension) - **Distal**: Between FCR tendon (palpable with wrist flexion) and radial styloid ### Superficial Dissection **1. Subcutaneous Layer:** - Incise skin and subcutaneous tissue sharply - Identify and protect **lateral antebrachial cutaneous nerve** (LABC) - runs longitudinally in subcutaneous fat lateral to incision - Ligate small superficial veins crossing surgical field **2. Fascia Incision:** - Identify **brachioradialis** muscle belly (lateral landmark) - Palpate **radial artery pulsation** between brachioradialis and FCR/PT (medial landmark) - Incise **deep fascia LATERAL to radial artery** (between artery and brachioradialis) ### Deep Dissection - Three Zones **ZONE 1: PROXIMAL 1/3 RADIUS (Elbow to Proximal Shaft)** **Interval:** Between brachioradialis (lateral, radial nerve) and pronator teres (medial, median nerve) **Steps:** 1. **Retract brachioradialis laterally** - exposes underlying supinator muscle and proximal radius 2. **Identify biceps tendon insertion** on radial tuberosity (deep medial landmark) 3. **Supinator muscle splitting:** - **CRITICAL**: Place forearm in **FULL SUPINATION** (migrates PIN anteriorly away from surgical field - Stern 1984) - Identify supinator covering proximal radius (extends from lateral epicondyle to radial shaft) - Split supinator in **LINE OF ITS FIBERS** (parallel to radius) using blunt dissection - Avoid deep dissection on dorsal radius (PIN on deep surface of supinator) 4. **Subperiosteal elevation** - elevate supinator from radius periosteum using elevator (exposes proximal radial shaft) **PIN Protection:** - PIN lies 2-5cm distal to radial head on **deep surface of supinator** (Spinner 1968) - **Full supination** increases safety clearance (PIN migrates anteriorly with supination) - Split supinator in line of fibers (NOT perpendicular to fibers) - Avoid dissection around radial neck (highest PIN concentration) **ZONE 2: MIDDLE 1/3 RADIUS (Mid-Shaft)** **Interval:** Between brachioradialis (lateral, radial nerve) and FCR (medial, median nerve) **Steps:** 1. **Identify radial artery** - lies between brachioradialis and FCR (use pulsation as landmark) 2. **Mobilize radial artery MEDIALLY:** - Incise fascia LATERAL to artery (between BR and artery) - Use **BLUNT dissection** to mobilize artery medially with FPL muscle and median nerve - Control artery with vessel loops if needed 3. **Retract brachioradialis laterally** - exposes FPL and radius shaft 4. **Identify FPL muscle** - covers volar radius in middle 1/3 5. **Subperiosteal elevation** - elevate FPL from radius periosteum (exposes mid-shaft radius) **Radial Artery Protection:** - **Medial mobilization** is safer than lateral retraction (reduces tension on artery) - Use **blunt dissection** (avoid sharp dissection near artery) - Vessel loops for control (NOT aggressive retraction) **ZONE 3: DISTAL 1/3 RADIUS (Distal Shaft to Metaphysis)** **Interval:** Between FCR (medial, median nerve) and brachioradialis tendon (lateral, radial nerve) **Steps:** 1. **Identify FCR tendon** - palpable with wrist flexion (medial landmark) 2. **Identify brachioradialis tendon** - inserts on radial styloid (lateral landmark) 3. **Identify superficial radial nerve (SRN):** - Emerges from under brachioradialis 6-9cm proximal to radial styloid - Crosses surgical field to dorsum of hand - **CRITICAL**: Protect with GENTLE MEDIAL retraction 4. **Incise deep fascia** - between FCR and brachioradialis 5. **Identify pronator quadratus (PQ):** - Covers distal radius volar surface (square muscle) - Extends from distal 1/4 radius to distal ulna 6. **Elevate PQ from radius:** - Incise PQ along radial (lateral) border - Elevate PQ MEDIALLY as flap (preserves muscle for closure) - Exposes distal radial metaphysis **SRN Protection:** - Identify SRN exiting from under BR tendon (6-9cm proximal to styloid) - **Gentle medial retraction** (NOT lateral traction) - Minimize retraction time (release retractors periodically) - Avoid electrocautery near nerve ### Radius Exposure and Fracture Fixation **Radius Periosteum:** - **Subperiosteal elevation** from fracture site using elevator - Preserve periosteal blood supply (minimize stripping at non-fracture zones) - Expose fracture site circumferentially (BUT avoid excessive dorsal dissection - interosseous membrane preserves vascular supply) **Fracture Reduction:** - **Direct manipulation** of proximal and distal fragments - **Reduction clamps** for provisional fixation - **Fluoroscopy** for reduction verification (AP and lateral views) **Plate Fixation:** - **3.5mm LC-DCP or LCP** plate on volar radius surface (standard implant) - **Screw fixation**: 6 cortices proximal and distal to fracture (AO principles - Chapman 1989) - **Plate position**: Centered on volar radius (avoid ulnar placement - interosseous membrane tension) - **Compression**: Dynamic compression with compression screws or lag screws through plate ### Closure **Deep Layers:** 1. **Pronator quadratus repair** (distal 1/3 dissection) - reattach PQ to radial border with interrupted sutures 2. **Supinator muscle repair** (proximal 1/3 dissection) - reapproximate supinator fibers (NOT MANDATORY - muscle heals spontaneously) 3. **Hemostasis** - meticulous cautery (avoid cautery near SRN or radial artery) **Superficial Layers:** 1. **Deep fascia closure** - interrupted absorbable sutures (2-0 Vicryl) 2. **Subcutaneous layer** - interrupted absorbable sutures (3-0 Vicryl) 3. **Skin closure** - running subcuticular (4-0 Monocryl) or interrupted nylon sutures **Postoperative:** - **Sugar tong splint** (prevents forearm rotation) for 7-10 days - **Wound check** at 1-2 weeks - **Early ROM** at 2 weeks (wrist/elbow/finger motion to prevent stiffness) - **Radiographic follow-up** at 2, 6, 12 weeks for union assessment ### Indications (When to Use Henry Approach) **PRIMARY INDICATIONS:** **1. Radial Shaft Fractures (MOST COMMON INDICATION):** - **Displaced fractures** with greater than 50% displacement or greater than 10° angulation - **Open fractures** (Gustilo I-IIIA) with volar wound (contraindication if volar contamination - use posterior Thompson approach) - **Both-bone forearm fractures** (Henry for radius, subcutaneous approach for ulna through SAME INCISION) - **Biomechanical advantage**: Volar plating in TENSION (resists bending forces better than dorsal plating) **2. Radial Nonunion/Malunion:** - **Nonunion** with inadequate fixation or infection - **Malunion** with functional impairment (loss of forearm rotation, reduced grip strength) - **Revision ORIF** with bone grafting (iliac crest autograft or allograft) **3. Forearm Pathology:** - **Radioulnar synostosis** takedown (single volar approach reduces re-synostosis risk to 2% - Vince 1990) - **Radial osteotomy** for angular deformity correction - **Tumor excision** (osteoid osteoma, enchondroma, bone metastases) - **Infection** (osteomyelitis with debridement and antibiotic cement spacer) - **Vascular injury** (radial artery repair or reconstruction) **RELATIVE INDICATIONS:** - Minimally displaced fractures with progressive displacement on serial X-rays - Fractures in polytrauma patients (facilitates early mobilization) - Pathological fractures (tumor, infection, osteoporosis) ### Contraindications (When NOT to Use Henry Approach) **ABSOLUTE CONTRAINDICATIONS:** - **Open fractures with volar contamination** (high infection risk - use posterior Thompson approach for debridement/fixation) - **Acute compartment syndrome requiring fasciotomy** (use dorsal approach for 4-compartment fasciotomy, delay ORIF) **RELATIVE CONTRAINDICATIONS:** - **Proximal radius fractures** involving radial neck (higher PIN injury risk with supinator splitting - consider antegrade nailing or posterior approach) - **Distal radius metaphyseal fractures** (consider volar plating via FCR approach - more direct distal exposure) - **Active soft tissue infection** (volar cellulitis or abscess - delay surgery until infection controlled) ### Outcomes **Union Rates:** - **Isolated radius fractures**: 95-98% union at 12-16 weeks (Chapman 1989) - **Both-bone fractures**: 92-95% union (slightly lower due to higher energy mechanism) - **Nonunion rate**: 2-3% (higher with inadequate fixation, smoking, NSAIDs) **Functional Outcomes:** - **Forearm rotation**: Mean 85-90% of contralateral side (limited by soft tissue scarring, NOT bone healing) - **Grip strength**: Mean 90-95% of contralateral side at 12 months - **Return to work**: Mean 12-16 weeks (manual labor), 6-8 weeks (sedentary work) **Complications:** - **Nerve injury**: 5-10% (SRN dysesthesia most common, 2% permanent - Ring 2004) - **Infection**: 2-3% (superficial 2%, deep 0.5-1%) - **Nonunion**: 2-3% (requires revision ORIF with bone grafting) - **Synostosis**: 2-9% (2% single incision, 9% dual incision - Vince 1990) - **Hardware irritation**: 10-15% (plate removal rate 10-12% at 12-18 months) ### Intraoperative Complications **1. RADIAL ARTERY INJURY (0.5-1%):** **Mechanism:** - Sharp dissection too close to artery (between BR and FCR) - Aggressive lateral retraction of artery (excessive tension) - Laceration during supinator splitting or periosteal elevation **Prevention:** - Use radial artery pulsation as LANDMARK (incise fascia lateral to artery) - Mobilize artery MEDIALLY with BLUNT dissection (safer than lateral retraction) - Control with vessel loops (NOT aggressive retractors) - Avoid sharp dissection near artery (use blunt elevator) **Management:** - **Recognition**: Pulsatile bleeding from surgical field - **Immediate control**: Direct pressure with gauze, then vascular clamps proximal/distal - **Repair options:** - **Primary repair** (less than 1cm defect) - 6-0 or 7-0 Prolene interrupted sutures - **Reverse interposition vein graft** (greater than 1cm defect) - reverse saphenous vein or cephalic vein graft - **Ligation** (LAST RESORT) - only if hand perfusion via ulnar artery is adequate (Allen test positive, pulse oximetry on thumb adequate) - **Vascular surgery consultation** MANDATORY for repair **Outcome:** - Primary repair: 95% patency at 6 months (Leversedge 2008) - Ligation: 5% hand ischemia risk (median artery contribution variable) **2. POSTERIOR INTEROSSEOUS NERVE (PIN) INJURY (2-5% in Proximal Dissection):** **Mechanism:** - Deep dissection through supinator in forearm pronation (PIN on deep surface) - Excessive retraction around radial neck - Direct trauma during periosteal elevation **Prevention:** - Place forearm in FULL SUPINATION during proximal dissection (migrates PIN anteriorly 4mm - Stern 1984) - Split supinator in LINE OF ITS FIBERS (parallel to radius) - Avoid deep dissection on dorsal radius (PIN lies on deep supinator surface) - Minimize retraction around radial neck **Recognition:** - Decreased triggered EMG during supinator splitting (if neuromonitoring used) - Postoperative finger/thumb extension weakness (EPL, EDC, EIP) - Wrist extension preserved (ECRL/ECRB innervated by radial nerve proximal to PIN origin) **Management:** - **Immediate**: If recognized intraoperatively, release supinator and reposition retractors - **Postoperative palsy**: - Observation for 3-6 months (90% spontaneous recovery - Ring 2004) - Dynamic splinting (tenodesis splint for finger/thumb extension) - Nerve exploration if no recovery by 6 months (neurolysis vs nerve grafting) - Tendon transfers if no recovery by 12 months (PT to ECRB, FCR to EDC, PL to EPL) **Outcome:** - 90% spontaneous recovery by 6 months - Permanent deficit rare (less than 1%) ### Postoperative Complications **1. SUPERFICIAL RADIAL NERVE (SRN) DYSESTHESIA (5-10%):** **Mechanism:** - Excessive retraction during distal dissection - Traction injury from retractors - Electrocautery injury **Clinical Manifestation:** - Painful dysesthesia over dorsal thumb/index finger web space (SRN distribution) - Painful neuroma at SRN injury site - Hypersensitivity to light touch **Prevention:** - Identify SRN exiting from under BR (6-9cm proximal to styloid) - Gentle MEDIAL retraction (avoid stretching) - Avoid electrocautery near SRN - Minimize retraction time (release retractors periodically) **Management:** - **Transient dysesthesia** (most cases): - Observation for 3-6 months (spontaneous resolution in 80%) - Desensitization therapy (massage, graded textures) - Neuropathic pain medications (gabapentin 300mg TDS, amitriptyline 25mg nocte) - **Persistent neuroma** (2% cases): - Neuroma excision if symptoms persist beyond 6 months - Nerve transfer to deeper tissue (to avoid repeated trauma) - Consider nerve grafting if large nerve defect **Outcome:** - 80% resolve spontaneously by 6 months - 2% permanent dysesthesia (Ring 2004) **2. NONUNION (2-3%):** **Risk Factors:** - Inadequate fixation (less than 6 cortices proximal/distal) - Excessive periosteal stripping (devascularizes fracture site) - Smoking (10-fold increased nonunion risk) - NSAIDs (COX-2 inhibitors safe, traditional NSAIDs increase nonunion risk) - Infection (deep infection 5% nonunion risk) **Diagnosis:** - Persistent pain at fracture site beyond 4 months - Radiographic: No bridging callus at 6 months, persistent fracture line, hardware loosening/failure **Management:** - **Revision ORIF with bone grafting:** - Remove failed hardware - Debride nonunion site to bleeding bone - Iliac crest autograft (gold standard) or allograft - Larger plate (3.5mm LCP with locking screws) - Longer fixation (8-10 cortices proximal/distal) - **Adjuncts**: Bone morphogenetic protein (BMP-2 or BMP-7), low-intensity pulsed ultrasound (LIPUS) - **Smoking cessation**: MANDATORY (10-fold reduced union rate if continued smoking) **Outcome:** - Revision ORIF with bone grafting: 85-90% union (Chapman 1989) - Persistent nonunion: Vascularized bone graft (less than 5% cases) **3. RADIOULNAR SYNOSTOSIS (2-9%):** **Risk Factors:** - Both-bone forearm fractures (vs isolated radius fracture) - Proximal 1/3 fractures (interosseous membrane narrower proximally) - High-energy mechanisms (Gustilo II-III open fractures) - Head injury (heterotopic ossification risk) - Delayed fixation (greater than 48 hours) - Dual incision approach (9% vs 2% single volar incision - Vince 1990) **Clinical Manifestation:** - Progressive loss of forearm rotation (supination/pronation) - Radiographic: Bone bridge between radius and ulna (usually proximal 1/3) **Prevention:** - **Single volar incision** for both-bone fractures (Henry for radius, subcutaneous for ulna) - Preserve interosseous membrane (avoid dissection between bones) - Prophylactic indomethacin 25mg TDS for 6 weeks (HIGH-RISK patients: head injury, proximal 1/3 fractures) - Early fixation (within 48 hours) **Management:** - **Observation** if asymptomatic (minimal functional impairment) - **Synostosis excision** if symptomatic: - Wait 12-18 months for maturation - Excise bone bridge - Interpose fat or silastic sheet (prevents recurrence) - Postoperative indomethacin 25mg TDS for 12 weeks - Aggressive ROM therapy **Outcome:** - Synostosis excision: 70-80% improved rotation (mean 40° gain) - Recurrence rate: 15-20% (higher if excised before maturation) **4. INFECTION (2-3%):** **Risk Factors:** - Open fractures (Gustilo II-III: 10-15% infection rate) - Diabetes, smoking, immunosuppression - Prolonged surgery (greater than 2 hours) - Inadequate soft tissue coverage **Clinical Manifestation:** - **Superficial** (2%): Erythema, drainage from incision, no deep involvement - **Deep** (0.5-1%): Persistent pain, fever, elevated CRP/ESR, purulent drainage, hardware loosening **Management:** - **Superficial infection**: - Oral antibiotics (flucloxacillin 500mg QDS or cephalexin 500mg QDS for 10-14 days) - Wound care (daily dressings) - Close monitoring (watch for progression to deep infection) - **Deep infection**: - **Irrigation and debridement** (I&D) - remove necrotic tissue, cultures for microbiology - **Hardware retention** if fracture healing progressing (biofilm formation common, but removal risks nonunion) - **Hardware removal** if nonunion or loose hardware (debridement + antibiotic cement spacer + revision ORIF after infection cleared) - **IV antibiotics** (6 weeks minimum) - guided by culture sensitivities (common: S. aureus, coagulase-negative staphylococci) **Outcome:** - Superficial infection: 95% resolution with oral antibiotics - Deep infection with hardware retention: 70-80% infection clearance (Zimmerli 2004) - Deep infection with hardware removal: 90-95% infection clearance (but nonunion risk if premature removal)

Anterolateral Approach to Radius (Henry)

Anterolateral Approach to Radius (Henry)