Combined Two-Incision Approach for Both-Bone Forearm Fractures

What it exposes. The combined two-incision approach gives independent, direct access to both the radial and ulnar diaphyses so each bone is reduced and plated through its own exposure: the volar Henry (or dorsal Thompson) to the radius and the direct dorsoulnar approach to the subcutaneous ulna. It is the workhorse exposure for ORIF of displaced both-bone forearm fractures in adults. Why two incisions, never one. The forearm is a functional joint whose motion depends on anatomic length, rotation and the radial bow. A single incision crossing the interosseous membrane strips the soft tissues of both bones, devascularises fragments and dramatically increases the rate of radioulnar (cross-union) synostosis - a complication that permanently abolishes pronation-supination and is extremely difficult to treat. Two separate incisions preserve the interosseous membrane, respect each bone's soft-tissue envelope, and allow early motion. Position & landmarks. The patient is supine on a radiolucent table with the affected arm on a hand table and a high-arm tourniquet. The limb is draped free so it can rotate from full supination (for the volar Henry radius exposure) to pronation (for the ulna and the dorsal Thompson radius exposure), letting both incisions be completed from one position. An image intensifier is brought in from the head of the table. Surface landmarks: for the volar Henry, the brachioradialis and flexor carpi radialis tendons (with the biceps tendon and radial styloid marking proximal and distal extent); for the dorsal Thompson, a line from the lateral epicondyle to Lister's tubercle; and for the ulna, the entire subcutaneous (dorsoulnar) border from olecranon to ulnar styloid. Incision planning. Mark two separate longitudinal incisions, each centred over its fracture under fluoroscopy, separated by a skin bridge of at least 5 to 7 cm of healthy skin. Never connect the incisions across the interosseous membrane.

All three exposures use a true internervous plane, so each interval can be developed without denervating muscle. Work the radius and the ulna as two independent dissections, protecting the PIN, the radial artery and leash of Henry, and the ulnar neurovascular bundle.

Structures at risk, by layer

Extensile options. The volar Henry extends proximally into the antecubital fossa to reach the bicipital tuberosity and elbow, and distally to the volar wrist and distal radius. The dorsal Thompson extends proximally to the lateral elbow and distally to the dorsal wrist. The ulnar approach runs along the entire subcutaneous border from olecranon to ulnar styloid, so it can be lengthened freely in either direction. Closure. Irrigate copiously and achieve meticulous haemostasis. Close the deep fascia loosely over each plate - do not strangulate muscle and never close across the interosseous space. Re-approximate the elevated origins of supinator or pronator where they were raised, then close subcutaneous tissue and skin, ensuring the skin bridge stays well perfused. A suction drain is rarely required.

• Both-bone forearm fracture ORIF - the principal operation done through this exposure.
• Isolated diaphyseal radius or ulna fractures, Monteggia and Galeazzi fracture-dislocations, and revision fixation or plate removal. Sequencing. As a general rule, reduce and plate the simpler, less comminuted fracture first - very often the ulna, because its straight subcutaneous border makes length and rotation straightforward to restore - then use the fixed bone as a template for length and rotation of the other. For highly comminuted fractures, restore length by using the plate as a bridge and confirm against the contralateral forearm. Restore the radial bow. The radius carries a single lateral bow of about 10 mm (range roughly 7 to 15 mm) with its apex near the junction of the middle and distal thirds, about 60 percent of forearm length from the distal end. Use pre-contoured 3.5 mm forearm plates and confirm magnitude, apex location and rotational alignment fluoroscopically before final screws.

Plating principles. Use a 3.5 mm limited-contact dynamic compression or locking compression plate; for a simple fracture aim for six cortices (three bicortical screws) each side, with longer bridge plates for comminution. Apply an interfragmentary lag screw for suitable oblique or spiral patterns before the neutralisation plate. The radial plate sits on the flat volar (tension) surface and the ulnar plate on the subcutaneous border; use locking screws in osteoporotic bone or periarticular comminution. Bone graft. Reserve autograft for genuine bone loss or marked comminution, and never place it in the interosseous space between the radius and ulna. Check the radioulnar joints. After fixation, assess the proximal radioulnar joint (exclude a Monteggia pattern - confirm the radial head is reduced and stable) and the distal radioulnar joint (exclude a Galeazzi pattern - confirm the ulnar head is stable) through a full arc of pronation and supination. If either is unstable, reduce and stabilise it.

Diaphyseal both-bone forearm fractures in adults are managed worldwide by open reduction and internal fixation with plating of both the radius and the ulna through two separate incisions. The principle that the forearm is a functional joint, requiring anatomic restoration of length, rotation and the radial bow, is common to the AO Foundation, BOA/BOAST guidance, AAOS, and the European (EFORT/advanced orthopaedic practice) and Australasian examination systems. Side-by-side principles (where guidance converges): | Body | Position on forearm shaft fractures | |------|-------------------------------------| | AO Foundation | Anatomic reduction and stable 3.5 mm plating of both bones; two separate approaches to preserve the interosseous membrane; early motion; lag screw and neutralisation for simple patterns, bridge plating for comminution | | BOA / BOAST (open fractures) | Urgent washout and staged soft-tissue care for open injuries; definitive fixation once the soft-tissue envelope permits; antibiotic and tetanus prophylaxis | | OTA / AAOS | Operative fixation for displaced adult both-bone fractures; non-operative only for undisplaced or low-demand patients | Population and outcome evidence: - Diaphyseal forearm fractures show a bimodal distribution - high-energy injuries in young adults (often men) and lower-energy fractures in older adults.

• Modern compression-plating series report union in the great majority of adult both-bone fractures, with functional outcome driven by restoration of the radial bow and rotation rather than by patient age. Global practice variation: In well-resourced settings, pre-contoured locking plates and routine fluoroscopy are standard and the volar Henry approach is the workhorse for the radius. In resource-limited settings the same biomechanical principles are achieved with standard small-fragment implants and the subcutaneous ulnar exposure is unchanged; external fixation has a limited role for polytrauma or open injuries as a temporising measure. Consent (globally applicable): discuss posterior interosseous or superficial radial nerve injury, radioulnar synostosis, non-union or mal-union with loss of the radial bow and restricted rotation, compartment syndrome, infection, symptomatic hardware, and the small possibility of re-operation for removal of metalwork or synostosis excision.