Posterior Elbow Approaches: Triceps-Sparing, TRAP, and Campbell - Step by Step

Overview Comparison Table

Flowchart

1. TRICEPS-SPARING APPROACH (Paratricipital / Bryan-Morrey)

First described by Alonso-Llames (1972); popularized by Bryan and Morrey for TEA

Step-by-Step

• Patient supine; bolster under ipsilateral scapula; elbow rests on chest bolster
• Sterile tourniquet applied; prophylactic IV antibiotics before inflation

• Posterior longitudinal midline incision centered over the olecranon
• Raise full-thickness medial and lateral fasciocutaneous flaps

• Identify and mobilize the ulnar nerve in its groove
• Prepare for anterior subcutaneous transposition (protects nerve throughout)

• Develop interval between the triceps muscle and the medial intermuscular septum
• Excise the medial intermuscular septum to create working space
• Elevate the triceps muscle off the posterior surface of the distal humerus subperiosteally
• Exposes: medial column, olecranon fossa, posterior trochlea

• Elevate triceps off the lateral intermuscular septum and posterior humerus
• The anconeus is also elevated in continuity, preserving its neurovascular supply
• Exposes: lateral column, olecranon fossa, posterior trochlea

• Release MCL and LCL to allow dislocation for implant insertion
• Deliver distal humeral shaft under the triceps

• Triceps insertion is intact - no tendon repair required
• Early active range of motion is permitted postoperatively

• Triceps tendon insertion completely preserved - no postoperative extension restriction
• No olecranon osteotomy risk (nonunion, hardware complications)
• Preserves anconeus innervation (dynamic posterolateral stability)
• Can be converted to olecranon osteotomy if needed
• Preferred approach for planned-TEA in elderly with unrepairable distal humerus fractures

• Limited articular visualization - inadequate for C3 fractures
• More complex dissection

2. TRAP APPROACH (Triceps-Reflecting Anconeus Pedicle)

Described by O'Driscoll; elevates triceps and anconeus as a single vascularized pedicle

Step-by-Step

• Lateral decubitus or prone, arm over a support; tourniquet applied

• Posterior longitudinal midline incision
• Raise medial and lateral fasciocutaneous flaps

• Identify ulnar nerve medially and protect throughout

• Use Kocher interval (between ECU and anconeus) to elevate the anconeus
• Elevate anconeus off the lateral epicondyle and posterior lateral humerus
• This forms the distal lateral portion of the pedicle flap
• Preserves radial nerve supply to anconeus (enters from proximal)

• Subperiosteal dissection from the subcutaneous border of the ulna medially
• Creates medial portion of the combined triceps-anconeus flap

• Anconeus flap is reflected proximally to expose the triceps insertion
• Triceps insertion is then sharply released from the olecranon
• The entire triceps-anconeus unit is reflected proximally
• Full posterior elbow joint is now visible, including:
  • Trochlear sulcus (used as articular template for reduction)
  • Posterior capitellum
  • Olecranon fossa

• Reattach the triceps-anconeus flap to the olecranon via transosseous sutures
• Postoperative triceps protection required (typically 6 weeks)

• Good posterior elbow exposure (better than paratricipital)
• Avoids olecranon osteotomy complications
• Anconeus neurovascular supply is preserved (blood supply from radial nerve enters proximally - safe when reflecting distally)
• Trochlear sulcus visible for articular reduction template

• Triceps completely released - risk of triceps dehiscence and extensor weakness
• Requires postoperative extensor mechanism protection
• More demanding technique than Campbell approach

3. CAMPBELL APPROACH (Triceps-Splitting)

The original Campbell approach uses a midline split through the triceps tendon and medial head

Step-by-Step

• Patient lateral decubitus or prone
• Arm draped free; sterile tourniquet applied
• For the elbow: arm positioned over a support with elbow flexed ~90°

• Posterior midline longitudinal incision
• Proximal extent: ~10-12 cm above olecranon tip
• Distal extent: along subcutaneous border of ulna as needed
• Raise full-thickness medial and lateral fasciocutaneous flaps

• Identify ulnar nerve in its groove medially
• Protect throughout the procedure

• Split the triceps tendon in the midline longitudinally
• Extend the split through the medial head of triceps proximally
• Distally, the split can be extended through the triceps insertion on the olecranon
  • Release Sharpey fibers at the olecranon to create medial and lateral fasciotendinous sleeves
• Subperiosteal dissection from the midline outward on both the medial and lateral columns

• Flex the elbow to improve articular visualization
• Partially excise the olecranon tip if further articular access is needed
• Exposes: medial column, lateral column, olecranon fossa, posterior trochlea

• The split can be extended proximally to the level of the radial nerve as it crosses the humeral shaft in the spiral groove

• For ORIF: medial and lateral collateral ligaments are preserved
• For TEA conversion: MCL and LCL may be released for dislocation

• Repair triceps tendon to olecranon via transosseous nonabsorbable braided sutures
• Some modifications (Gschwend) incorporate a flake of olecranon bone to improve healing
• Postoperative protection of the triceps repair required

• Technically easiest of the three approaches
• Good visualization for both ORIF and TEA
• Most familiar approach for trauma surgeons
• Easy intraoperative conversion from ORIF to TEA
• Extensile - can expose entire posterior humeral shaft to radial nerve level

• Disrupts triceps insertion - postoperative extension protection required (typically 4-6 weeks)
• Risk of extensor mechanism failure/avulsion
• Limited articular exposure compared to olecranon osteotomy

Summary of Surgical Approaches to the Posterior Elbow

Anatomical Key Points for All Three Approaches

When to Use Which Approach

DISTAL HUMERUS FRACTURE
        |
        ├── Elderly patient, TEA planned directly
        |       └── TRICEPS-SPARING (Paratricipital)
        |           - Fastest to TEA
        |           - Early motion
        |
        ├── ORIF planned, possible TEA conversion
        |   ├── Less comminuted (C1-C2) → TRICEPS-SPARING or CAMPBELL
        |   └── High comminution, full ORIF attempt → CAMPBELL
        |       - Best ORIF visualization
        |       - Easy conversion to TEA
        |
        ├── Complex articular (C3), need full joint view
        |       └── TRAP approach OR Olecranon Osteotomy
        |           (TRAP avoids osteotomy complications)
        |
        └── Associated complete triceps laceration
                └── VAN GORDER (Triceps Tongue) with V-Y plasty

🎬 SURGICAL VIDEO SCRIPT

Triceps-Sparing Paratricipital Approach for Distal Humerus Fracture ORIF

A Step-by-Step Operative Guide

PREOPERATIVE DECISION ALGORITHM

SCENE 1 - OPERATING ROOM SETUP & PREOPERATIVE CHECKLIST

Preoperative Checklist

SCENE 2 - PATIENT POSITIONING

1. Place patient supine on the operating table
2. Place a bolster under the ipsilateral scapula to elevate the shoulder
3. Rest the elbow on a sterile rolled sheet on the patient's chest - this supports the arm throughout the case and allows an assistant to adjust position
4. Surgeon and assistant stand on the side of the injury
5. Scrub nurse and arthroplasty/implant table on the contralateral side

• Place on a bean bag with elbow flexed over an arthroscopy positioner
• Useful when no surgical assistant is available

🎯 Tip: The supine position is preferred as the nurse can dynamically assist with arm positioning during reduction maneuvers.

SCENE 3 - SKIN INCISION

Steps:

• Extends 10-12 cm proximal to the olecranon tip (following the posterior midline of the arm)
• Curves slightly medial to the olecranon tip to avoid direct pressure over the incision
• Extends 5-6 cm distally along the subcutaneous border of the ulna

• Use sharp dissection in the subdermal plane
• Keep flaps thick to protect the blood supply
• Expose the full posterior elbow and distal arm

⚠️ Hazard: Avoid multiple thin-plane flaps. A single full-thickness medial flap and a single full-thickness lateral flap minimizes skin necrosis risk.

SCENE 4 - ULNAR NERVE IDENTIFICATION AND MOBILIZATION

Steps:

⚠️ Hazard: Traction injury to the ulnar nerve is the most common neurologic complication. Never retract it under tension. Check vessel loop position at every stage.

SCENE 5 - MEDIAL WINDOW (FIRST SURGICAL WINDOW)

Steps:

⚠️ Hazard: The ulnar nerve runs just anterior to this septum. It must be fully protected before excising the septum. Confirm the vessel loop position before proceeding.

• Medial column of the distal humerus
• Medial aspect of the olecranon fossa
• Posterior aspect of the medial trochlea

SCENE 6 - LATERAL WINDOW (SECOND SURGICAL WINDOW)

Steps:

• Lateral column of the distal humerus
• Lateral aspect of the olecranon fossa
• Posterior capitellum and lateral trochlea

⚠️ Hazard: The radial nerve enters the posterior compartment through the lateral intermuscular septum at the junction of the middle and distal thirds of the humerus (~7-10 cm above the lateral epicondyle). Do not extend the lateral dissection proximal to this level without formally identifying the nerve.

SCENE 7 - FRACTURE ASSESSMENT AND PROVISIONAL REDUCTION

Steps:

🎯 Tip: If articular visualization is insufficient through the paratricipital windows alone, a third Boyd interval window can be added between the anconeus and the lateral olecranon. This gives additional articular exposure without touching the triceps insertion. If still insufficient, convert to olecranon osteotomy at this point.

SCENE 8 - DEFINITIVE FIXATION

Stage 8A - Articular Segment Reconstruction

• Screws pass from lateral to medial through the capitellum and trochlea
• Trajectory should be perpendicular to the fracture line
• Countersink screw heads to avoid articular prominence

🎯 Tip: Supplementary implants for small fragments - mini-fragment plates, headless compression screws (e.g., Acutrak), or bioabsorbable pins. These must be placed so they do not block subsequent bicolumnar plate application.

Stage 8B - Column Fixation (Shaft to Articular Segment)

• In parallel plating: both plates lie roughly in the same coronal plane, one on each column
• Plates should interdigitate distally so screws from one plate pass between screws from the other

• Insert as many screws as possible through the plates into the articular segment
• Screws should be as long as possible to engage maximum bone stock
• Screws should engage as many articular fragments as possible
• Do NOT place screws through the olecranon fossa - this causes impingement and blocks extension

• Articular congruence
• Column alignment
• Screw length (no intra-articular prominence)
• No olecranon fossa screw

🎯 Tip: Orthogonal plating (90-90 configuration - one medial, one posterolateral) is equally effective biomechanically. Choose based on fracture pattern and surgeon familiarity. Triple plating adds a third implant for highly comminuted C3 patterns.

SCENE 9 - INTRAOPERATIVE CONVERSION CHECK

• Fixation is biomechanically insufficient
• Patient is elderly with high articular comminution
• Bone quality precludes adequate screw purchase

SCENE 10 - WOUND CLOSURE

Steps:

• If previously transposed anteriorly, now decide final position: anterior subcutaneous transposition vs. replace in groove
• Most surgeons perform formal anterior subcutaneous transposition when the nerve has been fully mobilized
• Secure the transposed nerve with a loose fascial sling (avoid tight constriction)

SCENE 11 - POSTOPERATIVE PROTOCOL

🎯 Key Advantage: Because the triceps insertion is completely intact, there is no postoperative extension restriction. Active elbow extension is permitted from day 1. This is the primary clinical advantage over the Campbell and TRAP approaches.

SCENE 12 - POTENTIAL PITFALLS AND HOW TO AVOID THEM

COMPLETE SURGICAL CHECKLIST (Quick Reference)

PRE-OP
  □ CT reviewed, fracture classified (AO type)
  □ Implants templated and available
  □ IV antibiotics given before tourniquet inflation
  □ Ulnar nerve baseline documented

POSITIONING
  □ Supine, ipsilateral scapula bolster
  □ Elbow on chest bolster
  □ Sterile tourniquet applied

APPROACH
  □ Posterior midline skin incision (curve medial to olecranon tip)
  □ Full-thickness fasciocutaneous flaps raised
  □ Ulnar nerve identified, vessel-looped, transposed anteriorly
  □ Cubital tunnel retinaculum released
  □ MEDIAL WINDOW: interval between triceps and MIS developed
  □ Medial intermuscular septum EXCISED
  □ Triceps elevated subperiosteally off medial column
  □ LATERAL WINDOW: triceps/anconeus elevated off lateral column
  □ Radial nerve level confirmed - do not dissect proximal

REDUCTION
  □ Hematoma irrigated
  □ Articular fragments identified
  □ K-wire joysticks used
  □ Elbow flexed 90° to improve visualization
  □ Provisional reduction confirmed on fluoroscopy

FIXATION
  □ Articular screw(s) along capitellar-trochlear axis
  □ Parallel (or orthogonal) bicolumnar plates applied
  □ Maximum screws into articular segment
  □ No screws in olecranon fossa
  □ Final AP + lateral fluoroscopy - articular congruence confirmed

CLOSURE
  □ Tourniquet released, hemostasis
  □ Ulnar nerve transposition secured
  □ Deep fascia closed - NO triceps repair needed
  □ Skin closed
  □ Posterior splint 90°

POST-OP
  □ Neurovascular check (ulnar nerve first)
  □ Elevation and ice
  □ Active ROM started day 1

🎬 SURGICAL VIDEO SCRIPT

TRAP Approach (Triceps-Reflecting Anconeus Pedicle) for Distal Humerus Fracture ORIF

A Step-by-Step Operative Guide

WHY THE TRAP APPROACH?

SCENE 1 - PREOPERATIVE SETUP & CHECKLIST

Indications for the TRAP Approach

• Intra-articular distal humerus fractures with moderate-to-high articular comminution where direct trochlear visualization is needed
• Cases where the surgeon wishes to avoid olecranon osteotomy complications (nonunion, hardware, ulnar nerve neuritis - reported at 33% in osteotomy series)
• Complex articular fractures where the trochlear sulcus is needed as a reduction template
• Intraoperative conversion from ORIF to TEA remains possible through the same exposure

Preoperative Checklist

⚠️ Important: Pre-brief the team that this approach involves complete triceps detachment. Postoperative extension restriction will be in place for 6 weeks. All team members should be aware.

SCENE 2 - PATIENT POSITIONING

1. Patient in lateral decubitus on a bean bag or padded support
2. Operative arm draped free over an arthroscopy arm positioner or padded support, elbow flexed approximately 90°
3. Arm positioned so elbow hangs free, allowing gravity-assisted retraction during the approach
4. Tourniquet on the upper arm, sterile field from mid-arm distally
5. Surgeon stands posterior to the patient; assistant on the opposite side

• Bolster under ipsilateral scapula
• Elbow rests on a folded sterile sheet on the patient's chest

🎯 Tip: The lateral decubitus position allows the arm to be repositioned (pronated/supinated, flexed/extended) freely during different phases - essential for visualizing anterior articular fragments via internal rotation of column fragments.

SCENE 3 - SKIN INCISION

Steps:

• Tip of the olecranon
• Medial epicondyle
• Lateral epicondyle

• Begin 10-12 cm proximal to the olecranon tip, in the posterior midline of the arm
• Curve slightly medial to the olecranon tip (avoids direct pressure over the incision post-op)
• Extend distally 6-8 cm along the subcutaneous border of the ulna (this distal extension is important for the TRAP - you need access along the full length of the ulnar border)

• Maintain the plane immediately on the deep fascia
• Thick flaps protect the subdermal plexus and reduce wound healing complications
• Expose the olecranon, medial epicondyle, and lateral epicondyle fully

⚠️ Hazard: The medial antebrachial cutaneous nerve branches cross the medial flap distally. Protect them during flap elevation to avoid dysesthesia.

SCENE 4 - ULNAR NERVE IDENTIFICATION AND TRANSPOSITION

Steps:

• Bluish-white cord, approximately 4-5 mm diameter
• First branch (to FCU) exits ~3 cm distal to the epicondyle

⚠️ Critical: Ulnar nerve neuritis was reported in 0% of TRAP/triceps-tongue cases vs 33% in olecranon osteotomy cases. The TRAP approach's zero neuritis rate depends on meticulous nerve handling.

SCENE 5 - LATERAL FLAP: KOCHER INTERVAL AND ANCONEUS ELEVATION

Understanding the Key Anatomy First:

• Kocher interval = the surgical plane between ECU (extensor carpi ulnaris) and anconeus
• The interval is marked by a thin fat stripe running longitudinally, or by the perforating branches of the recurrent posterior interosseous artery
• The anconeus originates from the lateral epicondyle and inserts broadly on the posterior ulna
• The anconeus receives its nerve supply (branch of radial nerve) proximally - therefore, reflecting it distally-to-proximally is safe and preserves innervation

Steps:

• Palpate the lateral epicondyle
• The interval runs from the lateral epicondyle distally along the posterior-lateral forearm
• Look for the thin fat stripe between ECU (anterior) and anconeus (posterior)

⚠️ Hazard: The posterior interosseous nerve (PIN) lies at risk if the interval is extended distally below the radial neck. Pronate the forearm during distal extension - this moves the PIN anteriorly and increases the safe working distance.

SCENE 6 - MEDIAL FLAP: SUBPERIOSTEAL DISSECTION FROM THE ULNAR BORDER

Steps:

🎯 Tip: Keep the dissection strictly subperiosteal throughout. Staying on bone avoids injury to the ulnar nerve (medially) and PIN (laterally), and keeps the flap vascular.

SCENE 7 - REFLECTING THE TRICEPS-ANCONEUS FLAP PROXIMALLY

Steps:

• Keep the release as close to bone as possible to preserve maximum tendon length for later reattachment
• Release proceeds from lateral to medial across the entire olecranon footprint

• Entire olecranon fossa
• Both medial and lateral columns
• Trochlear sulcus (key articular landmark - used as reduction template)
• Posterior capitellum
• Posterior trochlea

🎯 The Signature Advantage: The trochlear sulcus is now directly visible and can be used as a template for articular reduction - a unique benefit of the TRAP approach not available with the paratricipital or triceps-splitting approaches.

⚠️ Hazard: Keep the vessel loop on the ulnar nerve visible at all times. With the entire posterior joint now open, it is easy to lose sight of the nerve especially when placing retractors medially.

SCENE 8 - FRACTURE ASSESSMENT, REDUCTION, AND FIXATION

Stage 8A - Fracture Inventory

• Identify the capitellar fragment (lateral)
• Identify the trochlear fragment(s) (medial)
• Identify any free osteochondral fragments
• Confirm the trochlear sulcus is identifiable - this is the central reference point

Stage 8B - Articular Reconstruction: Trochlea-First Strategy

• The trochlear sulcus must be anatomically restored
• The capitellar articular surface must be flush with the lateral trochlear ridge

• Countersink screw heads to avoid articular prominence
• Confirm screw length on fluoroscopy (must not protrude beyond medial cortex)

Stage 8C - Column Fixation: Articular Segment to Shaft

• Medial column plate along the medial column
• Lateral column plate along the lateral column
• Plates sit roughly in the same coronal plane; distal screws from each plate interdigitate

• One plate on the posterior medial column
• One plate on the posterolateral column (90° to the first plate)

• Insert as many screws as possible through both plates into the articular segment
• Screws should be as long as possible, spanning the full width of the articular segment
• Each screw should engage as many articular fragments as possible
• Avoid the olecranon fossa - screws through the fossa cause impingement and block full extension

• Insert the first diaphyseal screw eccentrically in the plate's shaft holes to compress the supracondylar fracture site
• Fill remaining shaft holes with locking or cortical screws
• Minimum 3 bicortical shaft screws each side above the fracture

• Articular congruence
• Column reduction and alignment
• All screw lengths safe (no articular prominence, none through olecranon fossa)
• Carrying angle approximately correct

🎯 Tip: The TRAP approach allows the trochlear sulcus to guide articular reduction. Unlike the paratricipital approach where the articular surface is obscured by the intact triceps, here you can directly visualize and confirm articular congruence under direct vision before plating.

SCENE 9 - CHECK RANGE OF MOTION UNDER DIRECT VISION

• Normal flexion arc: 0-140° should be achievable
• Listen and feel for any crepitus or bony block

• Screw in olecranon fossa (remove and replace)
• Residual small bony fragment in the fossa (remove)
• Olecranon tip overhang (partial tip excision)

SCENE 10 - WOUND CLOSURE

Steps:

• Confirm the ulnar nerve is positioned in the anterior subcutaneous transposition
• Secure the transposition with a loose Z-plasty fascial sling (2-0 Vicryl) - the sling must allow finger to pass under it without resistance
• Remove the vessel loop

• One tunnel on the medial side of the olecranon
• One tunnel on the lateral side
• Optional third tunnel in the middle
• Tunnel orientation: from posterior (dorsal) olecranon surface through to the anterior (articular) surface of the triceps footprint

⚠️ Critical: Triceps dehiscence is the most feared complication of the TRAP approach. A weak or inadequate repair here directly leads to extensor mechanism failure. Use the strongest available suture; do not spare the number of passes.

SCENE 11 - POSTOPERATIVE PROTOCOL

Key difference from paratricipital approach: Because the triceps was fully detached and reattached, elbow extension is restricted for 6 weeks to protect the triceps repair.

SCENE 12 - PITFALLS AND HOW TO AVOID THEM

COMPLETE SURGICAL CHECKLIST (Quick Reference Card)

PRE-OP
  □ CT reviewed, fracture pattern mapped (AO/OTA type)
  □ Trochlear sulcus identifiable on CT (landmark for reduction)
  □ Bicolumnar plates templated; headless screw set available
  □ Contingency plan if conversion to TEA needed
  □ IV antibiotics before tourniquet inflation
  □ Ulnar nerve baseline documented

POSITIONING
  □ Lateral decubitus or supine with chest bolster
  □ Arm draped free
  □ Sterile tourniquet applied

APPROACH
  □ Posterior midline incision - curves medial to olecranon tip
  □ Extends distally 6-8 cm along subcutaneous ulnar border
  □ Full-thickness fasciocutaneous flaps raised medially and laterally
  □ Ulnar nerve identified, vessel-looped, anterior subcutaneous transposition
  □ LATERAL: Kocher interval (ECU/anconeus) incised; anconeus elevated from lateral epicondyle and lateral ulna, distal-to-proximal
  □ Forearm pronated during distal dissection (protects PIN)
  □ MEDIAL: Periosteal elevation off medial ulnar border, medial-to-lateral across posterior ulna
  □ Medial and lateral planes connected across posterior ulna
  □ Anconeus flap reflected proximally → triceps insertion exposed
  □ Triceps insertion sharply released from olecranon (close to bone)
  □ Triceps muscle elevated subperiosteally off posterior distal humerus
  □ Full posterior joint exposed; trochlear sulcus identified

REDUCTION & FIXATION
  □ Fracture hematoma irrigated
  □ All fragments inventoried vs. preop CT
  □ Trochlear sulcus used as primary reduction reference
  □ K-wire joysticks for fragment manipulation
  □ Articular segment reduced and provisionally K-wired
  □ Fluoroscopy confirms provisional reduction
  □ Definitive articular screws (capitellar-trochlear axis)
  □ Parallel or orthogonal bicolumnar plates applied
  □ Maximum screws into articular segment
  □ First diaphyseal screw eccentric (fracture compression)
  □ No screws in olecranon fossa
  □ Final AP + lateral + oblique fluoroscopy
  □ Intraoperative ROM check - no impingement

CLOSURE
  □ Tourniquet released; hemostasis; 3L irrigation
  □ Ulnar nerve transposition secured (fascial sling, finger passes freely)
  □ Vessel loop removed
  □ Transosseous bone tunnels drilled in olecranon (2-3 tunnels)
  □ Triceps reattached with FiberWire #2 Krackow through bone tunnels
  □ Repair tensioned in full extension and tied
  □ Repair integrity tested (flex/extend cycle under direct vision)
  □ Kocher interval fascia closed
  □ Deep fascia closed
  □ Drain placed
  □ Skin closed
  □ Posterior splint at 30-45° flexion

POST-OP
  □ Neurovascular check (ulnar nerve first)
  □ Elevation and ice
  □ Active hand/wrist exercises from day 1
  □ Elbow extension restricted 6 weeks (hinged brace)
  □ Active elbow extension begins week 6 (after radiograph)

TRAP vs PARATRICIPITAL - SIDE-BY-SIDE SUMMARY