High Yield Overview

SCAPHOID ORIF - DORSAL APPROACH (PROXIMAL POLE)

Dorsal approach through 3rd and 4th extensor compartment interval (EDC-EPL interval) or direct over Lister's tubercle | advanced

Mnemonic

D-O-R-S-A-LDORSAL ACCESS

Mnemonic

P-R-O-X-I-M-A-LPROXIMAL POLE PRIORITIES

Critical Danger Structures - 5 SPECIFIC Anatomical Zones

Danger 1: Dorsal Scaphoid Blood Supply

Location: Dorsal ridge of scaphoid (junction between waist and proximal pole) - dorsal carpal branch of radial artery enters through foramina at dorsal ridge

Protection: Minimal periosteal stripping. Create radially-based capsular flap. Use elevator gently only where necessary. Preserve soft tissue attachments at dorsal ridge. No aggressive curettage or debridement near dorsal surface.

Danger 2: Superficial Radial Nerve

Location: Terminal branches cross dorsal wrist in subcutaneous tissue radial to 3rd compartment, over radial border of anatomical snuffbox

Protection: Identify branches during skin incision. Protect with vessel loops and gentle retraction. Avoid cautery near nerve. Keep incision centered over Lister's (more ulnar than SRN branches).

Danger 3: Scapholunate Ligament

Location: Dorsal SL ligament runs from dorsal scaphoid to dorsal lunate just ulnar to scaphoid - strongest portion of SL complex

Protection: Capsulotomy OVER scaphoid, not extending ulnarly into SL interval. Gentle capsular elevation. Avoid instruments in SL interval. Careful reduction maneuvers - no excessive rotation.

Danger 4: Extensor Pollicis Longus

Location: EPL tendon in 3rd compartment courses around Lister's tubercle with sharp turn, vulnerable to ischemia and rupture

Protection: Gentle retraction only. No prolonged tension. Preserve blood supply during retraction. Confirm smooth gliding after retinaculum repair. Warn patient of delayed rupture risk.

Danger 5: Radiocarpal Articular Cartilage

Location: Proximal scaphoid articular surface articulates with scaphoid fossa of distal radius - vulnerable to guidewire, screw, and instrument penetration

Protection: Fluoroscopic confirmation of wire position before drilling. Check screw length measurement twice. Avoid excessive force during reduction. Countersink screw head below articular surface with retrograde technique.

Absolute Indications

Displaced proximal pole fracture (Herbert B3) - displacement greater than 1mm
Proximal pole non-union - failed conservative management or delayed presentation
AVN of proximal pole - requires vascularized bone graft (1-2 ICSRA) + fixation

Relative Indications

Non-displaced proximal pole fracture in high-demand patient - athletes, manual laborers
Failed volar approach to proximal pole - inadequate visualization, unable to achieve fixation
Proximal pole fracture with scapholunate ligament injury - allows direct SL repair

Contraindications

Absolute

Severe comminution - fragment too small for any fixation (may need salvage procedures)
Active infection - relative emergency, debridement first

Relative

Severe osteoporosis - screw purchase inadequate, consider K-wire augmentation
Waist or distal pole fractures - volar approach preferred for better access

Pre-operative Planning

Imaging Requirements

Plain radiographs: PA, lateral, scaphoid views (PA with ulnar deviation), oblique
CT scan: Assess fragment size (can it accept screw?), displacement, comminution, arthritic changes
MRI: Essential to assess AVN (T1 dark signal indicates need for vascularized graft)

Decision Algorithm

Fragment size assessment: greater than 25% of scaphoid length required for retrograde screw
AVN assessment: If present on MRI, plan 1-2 ICSRA vascularized graft
Screw trajectory: Retrograde (proximal-to-distal) preferred; antegrade (distal-to-proximal) if fragment too small
Graft planning: Non-vascularized cancellous for non-union without AVN; vascularized ICSRA for AVN

Equipment Checklist

Mini C-arm positioned for perfect scaphoid views BEFORE draping
Headless compression screw set (variety of lengths 16-30mm)
0.045-inch guidewire, cannulated drill bits
K-wires for provisional fixation and joystick control
Microsurgical instruments if planning ICSRA vascularized graft
Wrist positioning bump for 10-20° flexion

Comprehensive Operative Steps

Step 1: Positioning & Dorsal Approach Planning

Positioning & Dorsal Approach Planning: Position forearm PRONATED with wrist flexed 10-20° over bump. This flexion opens up dorsal scaphoid space and brings proximal pole into operative field. Test C-arm for perfect PA, lateral, and oblique scaphoid views BEFORE draping. Mark Lister's tubercle - palpable dorsal prominence on distal radius. Plan incision centered on Lister's between 3rd and 4th compartments. Review imaging: proximal pole fracture location, displacement, size of proximal fragment.

Exam Pearl

Technical Tip: EXAM KEY: 'Dorsal approach is SPECIFICALLY for proximal pole fractures - provides direct visualization of proximal pole and access to dorsal blood supply. Wrist FLEXION (not extension like volar) opens dorsal scaphoid space. I palpate Lister's tubercle as key landmark. Forearm pronated. C-arm setup critical - proximal pole can be difficult to visualize on fluoroscopy. Dorsal approach allows screw insertion from proximal to distal (retrograde) or distal to proximal (antegrade) depending on fragment size.'

Dangers at this step

Wrong approach for waist fracture - volar preferred
Excessive wrist extension - closes dorsal scaphoid space
Poor C-arm setup - inadequate intraoperative imaging
Failure to assess fragment size pre-operatively

Step 2: Incision & Retinaculum Division

Incision & Retinaculum Division: 4cm longitudinal incision over Lister's tubercle extending from distal radius to carpus. Incise through skin and subcutaneous tissue. Identify and protect superficial radial nerve (SRN) branches with vessel loops. Identify extensor retinaculum. Incise retinaculum longitudinally between 3rd (EPL) and 4th (EDC) compartments. Elevate retinacular flaps for later repair. Identify EPL tendon in 3rd compartment (single tendon), EDC tendons in 4th compartment (multiple tendons).

Exam Pearl

Technical Tip: EXAM KEY: 'I make longitudinal incision over Lister's tubercle - this is the landmark separating 3rd and 4th extensor compartments. I identify SRN branches in subcutaneous tissue and protect them with vessel loops or gentle retraction. I incise retinaculum between EPL (3rd) and EDC (4th) - this is an INTERNERVOUS plane. EPL is posterior interosseous nerve, EDC is also PIN but different branches. I elevate retinacular flaps for later repair to prevent bowstringing. EPL is single tendon, EDC has 4 tendons to digits 2-5.'

Dangers at this step

SRN branch injury - painful neuroma and Wartenberg syndrome
EPL injury during retinaculum division
Incising wrong compartment
Inadequate retinacular flap elevation - difficult repair

Step 3: Retract EPL & Expose Capsule

Retract EPL & Expose Capsule: Retract EPL tendon RADIALLY (away from field). Retract EDC tendons ULNARLY. This exposes radiocarpal joint capsule over scaphoid. The capsule overlies proximal scaphoid and scapholunate interval. Identify Lister's tubercle on radius - this is reference point. Dorsal radiocarpal ligament (DRC) and dorsal intercarpal ligament (DIC) visible on capsule.

Exam Pearl

Technical Tip: EXAM KEY: 'I retract EPL radially and EDC ulnarly - this opens up the interval and exposes dorsal wrist capsule. The dorsal capsule contains important ligaments: DRC (radiocarpal) and DIC (intercarpal). The scaphoid proximal pole lies deep to this capsule, just radial to the scapholunate interval. I must preserve EPL blood supply during retraction - gentle traction only, no prolonged tension. Use self-retaining retractors carefully.'

Dangers at this step

Excessive EPL retraction - ischemia and delayed rupture
Inadequate exposure - poor visualization of proximal pole
Disorientation of anatomy - injury to SL structures
Damage to dorsal wrist ligaments

Step 4: Capsulotomy & Scaphoid Exposure - PRESERVE BLOOD SUPPLY

Capsulotomy & Scaphoid Exposure - PRESERVE BLOOD SUPPLY: Make CAREFUL longitudinal capsulotomy over proximal scaphoid. Create radially-based capsular flap to preserve DRC and DIC ligaments. Exposure reveals proximal pole of scaphoid. CRITICAL: Minimize periosteal stripping - the dorsal blood supply enters at dorsal ridge (area between waist and proximal pole). Use elevator gently. Remove minimal soft tissue. Identify fracture site. If non-union, fibrous tissue visible.

Exam Pearl

Technical Tip: EXAM KEY: 'This is the CRITICAL step - I must expose proximal pole while preserving dorsal blood supply. The dorsal vessels enter at the DORSAL RIDGE between waist and proximal pole - this is 70-80% of scaphoid blood supply. I create capsular flap with minimal periosteal stripping. Only remove soft tissue necessary for visualization. Aggressive stripping causes AVN. For acute fractures, hematoma present. For non-union, fibrous tissue or sclerotic bone. I preserve all soft tissue attachments at dorsal ridge where vessels enter.'

Dangers at this step

Excessive periosteal stripping - disrupts blood supply causing AVN
Injury to scapholunate ligament - causes SL dissociation and DISI
Inadequate exposure of proximal fragment - poor reduction
Joint cartilage damage during exposure

Step 5: Assess Fragment & Plan Fixation

Assess Fragment & Plan Fixation: Assess proximal pole fragment size. Small fragment (less than 25% scaphoid) may not accept screw. Assess displacement, rotation, and angulation. Clean fracture site gently - remove hematoma or fibrous tissue. For acute fracture with good fragment size, plan screw fixation. SCREW DIRECTION OPTIONS: (1) RETROGRADE (proximal to distal) - screw inserted from proximal pole into distal fragment. Preferred if proximal fragment large enough. (2) ANTEGRADE (distal to proximal) - screw from waist into proximal pole. Used if proximal fragment too small for retrograde.

Exam Pearl

Technical Tip: EXAM KEY: 'I assess proximal fragment size - this determines fixation strategy. Proximal pole fractures (Herbert B3) have high AVN risk due to tenuous blood supply. RETROGRADE screw (proximal to distal) preferred if fragment accepts screw - provides compression and good purchase. ANTEGRADE screw (distal to proximal, like volar approach) if fragment too small. For very small fragments (less than 25%), may need alternative fixation (K-wires, headless pins) or accept non-operative in elderly. For non-union with AVN, I plan vascularized bone graft (1-2 ICSRA) at this stage.'

Dangers at this step

Forcing screw into small fragment - causes fragmentation
Inadequate fracture site preparation - impedes union
Missed AVN on pre-op imaging - graft not planned
Failure to plan screw trajectory appropriately

Step 6: Fracture Reduction

Fracture Reduction: Reduce fracture anatomically. Techniques: (1) Joystick with 0.9mm K-wire in proximal fragment to control rotation and angulation. (2) Wrist positioning - slight flexion/extension to align fragments. (3) Direct manipulation with elevator or dental pick. Check reduction: cortical alignment on volar, dorsal, radial, ulnar sides. No articular step-off. Provisionally stabilize with K-wire if needed. Confirm reduction on fluoroscopy PA, lateral, and oblique.

Exam Pearl

Technical Tip: EXAM KEY: 'Dorsal approach allows direct visualization of proximal pole reduction - major advantage over percutaneous techniques. I use K-wire joystick in proximal fragment for precise control of rotation and angulation. Perfect reduction is CRITICAL - any malunion of proximal pole causes abnormal kinematics and arthritis. I check all cortical surfaces align on direct visualization and fluoroscopy. If reduction unstable or fragment too small, I use K-wire provisional fixation before screw. I confirm reduction on PA (no displacement), lateral (scapholunate angle 30-60°), and oblique (cortical alignment) views.'

Dangers at this step

Incomplete reduction - malunion causes arthritis and abnormal kinematics
Fragment comminution during manipulation
Loss of reduction during screw insertion
Iatrogenic SL injury with excessive manipulation

Step 7: Guidewire Placement - Retrograde Technique

Guidewire & Screw Insertion - Retrograde Technique: RETROGRADE (proximal to distal): With fracture reduced, place guidewire at CENTER of proximal pole articular surface. Aim wire parallel to scaphoid long axis toward distal pole. Check wire position on fluoroscopy - PA (central), lateral (parallel to dorsal cortex), oblique (no joint violation). Advance wire across fracture into distal fragment. Wire should be in center of distal scaphoid on all views. Confirm wire position before proceeding.

Exam Pearl

Technical Tip: EXAM KEY: 'For retrograde dorsal screw, I place guidewire at CENTER of proximal pole articular surface - this seems counterintuitive but headless screw buries completely below cartilage and heals over. Wire must be parallel to scaphoid long axis. CRITICAL: wire must be central on ALL fluoroscopy views - PA, lateral, and oblique. Eccentric wire causes malreduction or screw cutout. I advance wire carefully across fracture site maintaining reduction. Wire should reach distal pole cortex for measurement. Check wire position multiple times before drilling.'

Dangers at this step

Eccentric wire placement - fracture displacement or screw cutout
Wire trajectory not parallel to scaphoid axis - malreduction
Loss of reduction during wire insertion
Radiocarpal joint violation with wire
SL ligament injury during guidewire placement

Step 8: Screw Insertion - Retrograde Technique

Screw Insertion - Retrograde Technique: Measure screw length from proximal pole to distal scaphoid cortex. Drill with cannulated drill over guidewire. Insert headless compression screw. Screw head BURIES into proximal pole articular surface - must be countersunk BELOW cartilage level. Advance screw until leading threads engage distal fragment and compression achieved. Final fluoroscopy confirms screw position, fracture compression, no joint penetration.

Exam Pearl

Technical Tip: EXAM KEY: 'I measure screw length carefully - from proximal pole surface to distal cortex, usually 20-28mm for average scaphoid. I drill with cannulated drill - gentle pressure to avoid fragment comminution. Headless compression screw provides interfragmentary compression as trailing threads wider than leading threads. Screw head MUST countersink below articular cartilage surface - I confirm this on lateral fluoroscopy. Screw head proud above cartilage causes radiocarpal impingement. Cartilage heals over buried screw head - confirmed in literature. Final fluoroscopy shows screw centered in scaphoid, fracture compressed, no joint violation.'

Dangers at this step

Screw head proud above proximal pole - radiocarpal impingement and arthritis
Over-drilling - loss of screw purchase in small fragment
Screw too long - penetrates distal pole cortex or STT joint
Screw too short - inadequate compression
Fragment comminution during screw insertion

Step 9: Alternative - Antegrade Screw Technique

Alternative - Antegrade Screw Technique: ANTEGRADE (if proximal fragment too small for retrograde): Create small dorsal window at waist level. Place guidewire from waist directed PROXIMALLY into proximal pole fragment. Check wire central on all views. Wire should engage proximal pole fragment adequately (at least 10-15mm). Measure, drill, and insert headless screw from waist to proximal pole. Screw provides compression of proximal fragment onto distal. Countersink screw head at waist level below dorsal cortex.

Exam Pearl

Technical Tip: EXAM KEY: 'Antegrade technique is alternative if proximal fragment too small for retrograde screw entry (less than 25% scaphoid). I place guidewire from WAIST directed proximally into proximal pole - similar trajectory to volar approach but from dorsal. Advantage: larger entry point at waist allows easier screw insertion. Disadvantage: screw doesn't bury completely, head at waist level must be countersunk below dorsal cortex to avoid extensor irritation. I ensure adequate proximal pole engagement - minimum 10-15mm screw purchase in proximal fragment. This technique salvages fixation when proximal pole very small.'

Dangers at this step

Inadequate proximal pole engagement - screw pulls out, non-union
Screw head prominent dorsally - extensor tendon irritation
Fracture displacement during screw insertion from waist
Screw penetrates proximal pole articular surface into radiocarpal joint

Step 10: Bone Grafting if Non-Union or AVN

Bone Grafting if Non-Union or AVN: For proximal pole non-union or AVN, bone grafting essential. OPTIONS: (1) Non-vascularized cancellous from distal radius - harvest from same incision, window in radius 2cm proximal to joint, pack around fracture site. (2) Vascularized bone graft (1-2 ICSRA) - pedicled bone graft based on 1st or 2nd dorsal intercompartmental supraretinacular artery, for AVN with dark MRI signal. ICSRA graft: identify artery between 1st-2nd or 2nd-3rd compartments, harvest bone from radius with arterial pedicle, rotate into scaphoid non-union site, screw fixation through graft.

Exam Pearl

Technical Tip: EXAM KEY: 'Proximal pole non-union has high failure rate without bone graft due to tenuous blood supply. For NON-UNION without AVN: non-vascularized cancellous graft from distal radius adequate - I harvest through small window 2cm proximal to joint, pack graft around non-union site after debridement to bleeding bone. For AVN (MRI T1 dark signal): vascularized bone graft ESSENTIAL - non-vascularized fails. 1-2 ICSRA graft is pedicled vascularized graft from dorsal distal radius based on supraretinacular vessels between compartments. I identify vessel between 1st-2nd compartments (or 2nd-3rd), harvest rectangular bone block 8x15mm with pedicle attached, rotate 90° into scaphoid defect, provides both blood supply and structural support. Union rate 85-90% with ICSRA vs 50% without in AVN cases.'

Dangers at this step

Inadequate debridement of non-union site - persistent non-union
ICSRA pedicle injury - graft becomes non-vascularized and fails
Graft too large - disturbs scaphoid anatomy and kinematics
Not addressing AVN with vascularized graft - high failure rate
Donor site morbidity from radius graft harvest

Step 11: Confirm Fixation and Final Fluoroscopy

Confirm Fixation and Final Fluoroscopy: Perform final fluoroscopy views - PA, lateral, oblique. Confirm: (1) Screw position central in scaphoid on all views, (2) Screw head buried below proximal pole cartilage (retrograde) or waist cortex (antegrade), (3) Fracture anatomically reduced with no gap, (4) No joint penetration, (5) Adequate screw length and engagement. Test fracture stability under direct vision. Document intraoperative findings and images.

Exam Pearl

Technical Tip: EXAM KEY: 'Final fluoroscopy is critical quality control step. I obtain perfect PA, lateral, and oblique views. On PA: screw should be centered in scaphoid, no displacement. On lateral: screw parallel to scaphoid axis, scapholunate angle 30-60° (no DISI), screw head buried. On oblique: no joint violation, screw centered. I test fracture stability by gentle manipulation - should be rigid with screw fixation. If any concern about reduction or screw position, I revise NOW rather than accept suboptimal fixation. Document all findings for operative note and patient discussion.'

Dangers at this step

Accepting suboptimal reduction - leads to malunion
Missing joint penetration - causes arthritis
Inadequate documentation - medicolegal issues
Excessive radiation exposure to hands

Step 12: Capsular and Retinacular Repair

Capsular and Retinacular Repair: Irrigate wound thoroughly. Repair dorsal capsule with 3-0 absorbable suture using interrupted or figure-of-8 technique to restore ligamentous stability. Ensure SL ligament intact and stable. Repair extensor retinaculum between 3rd and 4th compartments with 3-0 absorbable suture. Check EPL glides smoothly through 3rd compartment over Lister's tubercle without bowstringing.

Exam Pearl

Technical Tip: EXAM KEY: 'Capsular repair is important to restore proprioception and dorsal wrist stability. I use 3-0 absorbable suture with interrupted or figure-of-8 technique. Retinaculum repair is CRITICAL - prevents EPL bowstringing which causes loss of thumb extension power and potential delayed rupture. I reconstruct the retinaculum between 3rd and 4th compartments, ensuring EPL courses through Lister's tunnel properly. I test EPL gliding by passive thumb IP flexion/extension - should glide smoothly without catching. Extensor tendon adhesions are risk with dorsal approach - meticulous repair minimizes this.'

Dangers at this step

Inadequate retinaculum repair - EPL bowstringing and rupture risk
Capsule not repaired - proprioceptive deficits and instability
Over-tight retinaculum repair - EPL stenosis and triggering
Injury to EPL during repair

Step 13: Skin Closure and Dressing

Skin Closure and Dressing: Close subcutaneous tissue with 4-0 absorbable suture. Close skin with 4-0 or 5-0 nylon interrupted sutures or running subcuticular absorbable suture. Apply sterile dressing. Apply well-padded thumb spica splint with wrist neutral, thumb in column position (IP joint free for motion). Confirm adequate padding over bony prominences and no constriction.

Exam Pearl

Technical Tip: EXAM KEY: 'I close in layers - subcutaneous 4-0 absorbable, skin with interrupted nylon or running subcuticular. For hand surgery, I prefer interrupted nylon for easier removal and wound inspection. Post-op splinting is CRITICAL: thumb spica with wrist neutral (not extended), thumb column position, IP joint FREE for motion to prevent stiffness. Immobilization protocol same as volar approach: thumb spica 6-8 weeks until union. However, proximal pole fractures take LONGER to unite - typically 12-20 weeks. I warn patients about prolonged healing time and AVN risk (30-50%).'

Dangers at this step

Wound tension - dehiscence or necrosis
Thumb IP joint immobilized - stiffness
Inadequate padding - pressure sores
Splint too tight - compartment syndrome or vascular compromise

Complications - Recognition, Prevention, and Management

Major Complications of Scaphoid ORIF - Dorsal Approach

Post-operative Care Protocol

Immediate Post-operative (0-2 weeks)

Immobilization

Thumb spica splint with wrist neutral, thumb column position
IP joint FREE for active motion (prevents stiffness)
Elevate hand above heart for 48-72 hours
Ice therapy for pain and swelling

Wound Care

Keep surgical dressing clean and dry
Suture removal at 10-14 days
Monitor for infection (rare, less than 1%)

Pain Management

Multimodal analgesia: acetaminophen + NSAIDs (if no contraindication)
Short course of opioids (3-5 days) for severe pain
Cryotherapy

Early Post-operative (2-8 weeks)

Immobilization

Convert to thumb spica cast at 2 weeks
Continue casting for 6 weeks total (8 weeks from surgery)
LONGER than waist fractures due to proximal pole tenuous blood supply

Radiographic Follow-up

X-rays at 2, 6 weeks: assess fracture position, no hardware loosening
Expect minimal callus (scaphoid is intra-articular, limited periosteal reaction)

Activity Restrictions

No lifting, pushing, pulling with affected hand
Light ADLs with splint on (eating, typing)
No sports or heavy labor

Mid Post-operative (8-12 weeks)

Mobilization

Removable thumb spica splint at 8 weeks IF early union signs
Begin hand therapy: AROM wrist and thumb
Gentle strengthening at 10 weeks
Continue splint protection between exercises

Radiographic Follow-up

X-rays at 8, 12 weeks
CT scan often needed to confirm union (proximal pole union difficult to see on plain films)
Union typically 12-20 weeks (LONGER than waist fractures)

Activity Progression

Light resistive activities at 10 weeks
Gradual return to work (office work 8-10 weeks, manual labor 12-16 weeks)

Late Post-operative (3-6 months)

Advanced Rehabilitation

Progressive strengthening program
Proprioceptive training
Return to sports protocol

Radiographic Follow-up

X-rays at 16, 20 weeks if union uncertain
CT scan gold standard for confirming union
MRI at 3-6 months if concern for AVN (T1 signal assessment)

Return to Full Activity

Unrestricted activity at 4-6 months after solid union
Contact sports at 6 months minimum (LATER than waist fractures)
Counsel patient: AVN can develop in 30-50% even with optimal surgery

Long-term Follow-up (greater than 6 months)

Monitoring

Annual X-rays first 2 years to detect AVN or SNAC arthritis
Hardware removal rarely needed (5-10% for symptomatic prominence)
Patient education on signs of non-union, AVN, arthritis

Expected Outcomes

Union rate: 80-85% for acute fractures with ORIF
ROM: 80-90% of contralateral wrist
Grip strength: 85-95% of contralateral
Return to pre-injury activity: 85% of patients at 1 year

Exam Viva Scenarios

Practice these scenarios to excel in your viva examination

VIVA SCENARIOStandard

EXAMINER

"Why does the proximal pole have such high AVN risk and how does this influence your surgical approach?"

EXCEPTIONAL ANSWER

The proximal pole has the HIGHEST AVN risk (30-50%) of any scaphoid region due to unique vascular anatomy. The scaphoid receives blood supply from: (1) Dorsal vessels (70-80%): dorsal carpal branch of radial artery enters at DORSAL RIDGE (junction of middle and proximal thirds) through multiple foramina. (2) Volar vessels (20-30%): volar branches enter at tubercle and waist. CRITICAL CONCEPT: The proximal pole has NO direct blood supply - it receives 100% of its blood via RETROGRADE intraosseous flow from the dorsal ridge vessels. When a proximal pole fracture occurs, this retrograde flow is INTERRUPTED. The proximal fragment becomes essentially avascular. Compare to waist fractures where proximal fragment still has some retrograde flow from dorsal vessels, and distal fractures which have excellent volar supply. Surgical implications: (1) I preserve dorsal blood supply by MINIMAL periosteal stripping during exposure. (2) Create radially-based capsular flap. (3) Only remove soft tissue essential for visualization. (4) Preserve ALL attachments at dorsal ridge. (5) If pre-op MRI shows AVN (T1 dark signal), I plan 1-2 ICSRA vascularized bone graft to provide revascularization. (6) Counsel patient pre-operatively about 30-50% AVN risk despite optimal technique.

VIVA SCENARIOStandard

EXAMINER

"What is the 1-2 ICSRA vascularized bone graft and when do you use it for proximal pole non-union?"

EXCEPTIONAL ANSWER

ICSRA stands for Intercompartmental Supraretinacular Artery. These are small dorsal vessels (0.5-1mm diameter) running between extensor compartments on the dorsal distal radius. The 1-2 ICSRA refers to the artery between the 1st compartment (APL/EPB) and 2nd compartment (ECRL/ECRB). The 2-3 ICSRA is between 2nd and 3rd (EPL) compartments. TECHNIQUE: Through the same dorsal approach for proximal pole fixation, I identify the ICSRA between compartments - it's a small vessel coursing on the dorsal radius surface. I harvest a rectangular bone block (8-10mm x 15-20mm) from the dorsal radius with the artery pedicle attached (pedicled vascularized graft). I rotate the graft 90 degrees into the proximal pole non-union site after debridement. Screw fixation through the graft into the distal scaphoid provides compression and stability. The arterial pedicle provides REVASCULARIZATION to the avascular proximal pole. INDICATIONS: (1) Proximal pole non-union WITH AVN on MRI (T1 dark signal) - this is ESSENTIAL indication. (2) Failed previous non-vascularized graft for proximal pole. (3) Proximal pole non-union with small fragment size where non-vascularized graft insufficient. OUTCOMES: Union rate 85-90% with ICSRA vascularized graft for AVN proximal pole, versus only 50-60% with non-vascularized graft. The graft provides both structural support AND revascularization. MRI at 3 months post-op shows improved T1 signal indicating revascularization. This is superior to free vascularized grafts (medial femoral condyle) for proximal pole due to easier technique and same outcomes.

VIVA SCENARIOStandard

EXAMINER

"Explain the differences between retrograde and antegrade screw fixation for proximal pole fractures - when would you use each technique?"

EXCEPTIONAL ANSWER

Proximal pole scaphoid fractures can be fixed with screws in two directions: RETROGRADE (proximal to distal) or ANTEGRADE (distal to proximal). RETROGRADE TECHNIQUE: Guidewire placed at CENTER of proximal pole articular surface. Screw inserted from proximal pole into distal fragment. Screw head BURIES into proximal pole articular cartilage below the surface. ADVANTAGES: (1) Best interfragmentary compression of fracture site. (2) Excellent screw purchase if fragment adequate size. (3) Direct visualization of proximal pole with dorsal approach. (4) Screw head buried in cartilage heals over with no impingement. DISADVANTAGES: (1) Requires adequate proximal fragment size (greater than 25% scaphoid length). (2) Technically challenging wire placement on articular surface. (3) Concern about screw head on articular cartilage (though literature confirms this heals). INDICATIONS: Proximal pole fractures with fragment greater than 25% scaphoid, adequate bone quality. ANTEGRADE TECHNIQUE: Guidewire from waist directed PROXIMALLY into proximal pole. Screw from waist to proximal pole. Screw head at waist level countersunk below dorsal cortex. ADVANTAGES: (1) Larger entry point at waist - easier screw insertion. (2) Can salvage fixation when proximal fragment too small for retrograde. (3) Similar trajectory to volar approach. DISADVANTAGES: (1) Screw head at waist doesn't bury completely - must countersink to avoid extensor irritation. (2) May provide less compression than retrograde. (3) Requires adequate proximal pole engagement (10-15mm minimum). INDICATIONS: Proximal pole fractures with fragment less than 25% scaphoid, inability to achieve retrograde screw placement. BIOMECHANICS: Studies show no significant difference in compression between retrograde vs antegrade IF wire placement perfectly central. Clinical preference: RETROGRADE for adequate fragments, ANTEGRADE for small fragments.