Management of Distal Humerus Fractures: Principles, Techniques, and Complications

Priorities in Fracture Management

• Surgical goals must follow a strict hierarchy of precedence.
• Higher-ranked priorities must not be compromised for lower-ranked ones.
• If joint congruence cannot be maintained, motion must be withheld.

Surgical Approach & Ulnar Nerve Handling

• Surgical Approach: An olecranon osteotomy provides the most reliable exposure for complex intra-articular distal humerus fractures.
• Ulnar Nerve Debate: Routine anterior transposition creates subcutaneous flaps that increase the risk of hematoma and wound infection.
• Transposition Indication: Transpose the ulnar nerve if it directly contacts hardware (especially titanium plates) at closure to prevent neural tethering and perineural fibrosis.

Biomechanics of Failure: Parallel vs. Perpendicular Plating

• Mode of Failure: Open reduction and internal fixation (ORIF) typically fails by non-union at the supracondylar level.
• Gravitational Load: Upper extremity usage exposes the lateral column to varus gravitational torque.
• Sagittal Plating Risk: A plate placed on the posterior aspect of the lateral column experiences tensile distraction, pulling away from bone.
• Parallel Plate Architecture: Plates placed along the medial and lateral margins resist varus-valgus bending and rotational stress significantly better than 90-90 (orthogonal) plating.

Biomechanical Principles & Technical Objectives

• Fundamental Rule 1: Maximize structural fixation within the distal fragments.
• Fundamental Rule 2: Ensure all distal fixation directly contributes to supracondylar stability.

The Technical Objectives Checklist

• Every screw in the distal fragments should pass through a plate.
• Every distal screw must anchor into a fragment secured by the contralateral plate.
• Distal screws must be as long as possible.
• Distal screws must engage as many articular fragments as possible.
• Distal screws should interdigitate and lock together in the center to create a rigid arch.
• Apply plates under axial compression at the supracondylar level.
• Use plates that are stiff and strong enough to prevent fatigue failure before union.

Step-by-Step Surgical Technique

• Step 1: Articular Reduction
  • Reduce articular fragments anatomically.
  • Stabilize provisionally using smooth Kirschner wires.
• Step 2: Plate Application & Provisional Fixation
  • Apply pre-contoured parallel plates to the medial and lateral columns.
  • Place 2.0 mm guide pins through the distal epicondylar plate holes into the bone.
  • Leave these pins in place to reserve pathways for definitive distal screws.
• Step 3: Distal Fragment Fixation
  • Drill and place distal screws around the reserved epicondylar pins without hardware collision.
• Step 4: Supracondylar Compression
  • Loosen the proximal shaft screw in the slotted hole on one column.
  • Apply dynamic compression across the supracondylar fracture zone using a large tenaculum clamp.
  • Drill eccentrically and tighten a dynamic compression screw on the shaft.
  • Repeat supracondylar compression on the contralateral column.
• Step 5: Final Screw Insertion
  • Remove the provisional 2.0 mm guide pins.
  • Advance the final long locking or cortex screws through the prepared epicondylar holes.

Complex Patterns: Coronal Shear Fractures

• Coronal shear fragments (capitellum and trochlea) do not require a posterior plate.
• Step 1: Drive two screws from medial to lateral through the plate into the anterior coronal shear fragment.
• Step 2: Place two lateral-to-medial screws through the lateral plate, interdigitating them with the medial screws.
• Step 3: Place one or two screws from posterior to anterior to lock the construct in the third dimension.

Supracondylar Bone Loss: The SOS Procedure

• Indication: Severe supracondylar comminution or bone loss preventing column-to-column contact.
• Technique: Perform a Supracondylar Osteotomy and Shortening (SOS).
• Re-sect or trim the humeral shaft to fit the distal articular segment.
• Obtain end-to-end bone contact on both columns, or end-to-end contact on one column and side-to-side overlap on the other.
• Overlap can be bridged with adjacent cortical spikes (e.g., bone fragments with brachioradialis origin).
• Compress the distal articular segment rigidly onto the shortened diaphysis.
• Preventing Fossa Impingement:
  • Recreate the olecranon fossa by burring bone proximally.
  • Shift the distal articular segment slightly anteriorly to maintain the coronoid fossa clearance.

Specialized Fixation, Rehabilitation & Wound Complications

• Olecranon Osteotomy Repair: Utilize a Harris wire tightener for tension-band wiring to achieve maximal wire tension with a low-profile twist knot.
• Immediate Postoperative Management:
  • Apply a well-padded anterior plaster splint (Jones-type dressing) with the elbow in extension.
  • Maintain splinting for at least 5 days (or until open wounds heal) to reduce posterior skin tension, wound blister formation, and hematoma.
  • Elevate the limb, but lower it for 5 minutes every hour to prevent forearm compartment syndrome.
• Posterior Wound Dehiscence & Infection Management:
  • Debride necrotic margins thoroughly.
  • Apply negative pressure wound therapy (wound VAC) for approximately 5 weeks.
  • Transition to daily wet-to-dry dressings with 0.025% Dakin’s solution.
  • Allow the stable hardware and bone to granulate beneath a clean-contaminated bed.
  • Remove hardware only after complete CT-confirmed osseous union.
  • Elevate local skin edges and close the wound primarily; avoid regional muscle flaps.