Medial Approach to the Arm and Distal Humerus

What it exposes. Henry's medial approach to the brachium exposes the medial humeral shaft and the brachial neurovascular bundle (brachial artery, median nerve and ulnar nerve) by developing the interval along the medial intermuscular septum between the biceps and brachialis anteriorly and the triceps posteriorly. It is the principal extensile route to the brachial artery in the arm and gives simultaneous access to the ulnar and median nerves. Why this approach is chosen. The medial aspect of the arm carries the brachial neurovascular bundle deep to the medial intermuscular septum. When pathology involves these structures - vascular injury, nerve compression, or medial cortical bone disease - the medial approach delivers direct and extensile access along a true internervous plane. For isolated humeral shaft fracture fixation it is a secondary option, because the anterolateral and posterior approaches provide better working room and radial nerve visualisation. Position & landmarks. Position the patient supine with the arm abducted approximately 90 degrees on a padded arm board or hand table and externally rotated, so the medial intermuscular septum faces the surgeon; apply a high-arm tourniquet and inflate after exsanguination. For distal ulnar nerve work, the arm across the chest with the elbow flexed is a practical alternative. Palpate the groove between biceps and triceps (overlying the medial intermuscular septum), the medial supracondylar ridge and medial epicondyle distally, and the deltopectoral groove proximally; mark the planned longitudinal incision along the medial border of the arm and the anticipated course of the basilic vein and medial antebrachial cutaneous nerve. Confirm C-arm access from the opposite side when imaging is required.

Primary indications:

• Exploration and repair of the brachial artery (penetrating vascular trauma, iatrogenic injury, or vascular compromise after supracondylar humerus fracture)
• Ulnar nerve decompression or anterior transposition in cubital tunnel syndrome when extensile proximal release is required
• Median nerve exploration in the arm (entrapment, traumatic injury, tumour)
• Exposure of the medial humeral cortex for tumour resection or biopsy, chronic osteomyelitis, sequestrectomy, or medial-based delayed union and nonunion
• Limited medial-column distal humerus fracture fixation where direct medial access is required
• Concurrent vascular and skeletal procedures needing medial humeral and brachial vessel access through one incision Contraindications:
• Most humeral shaft fractures (anterolateral or posterior approaches are preferred)
• Compromised or heavily scarred medial-arm soft tissue from previous surgery or trauma
• When broad posterior or lateral cortical visualisation is the primary goal
• Poor soft-tissue envelope over the planned medial incision

Alternative approaches:

• Anterolateral approach (Henry) - workhorse for humeral shaft fracture fixation; exposes the radial nerve in the distal arm
• Posterior approach - best for visualising the radial nerve in the spiral groove and for the posterior humeral shaft
• Minimally invasive anterior plating - for select diaphyseal fractures
• Functional (Sarmiento) bracing - non-operative management for the majority of closed humeral shaft fractures

Work down through the layers along the medial border of the arm, protecting the basilic vein and medial antebrachial cutaneous nerve superficially, then develop the true brachialis-triceps internervous plane on the medial intermuscular septum to reach the neurovascular sheath and the medial humeral cortex.

Structures at risk, by layer

Extensile options. Extend proximally toward the axilla and the deltopectoral groove, developing the plane between deltoid and pectoralis major, to reach the proximal humerus, the axillary vessels and the cords of the brachial plexus - the basis for combined shoulder-arm and vascular exposure. Extend distally to the medial epicondyle and into the cubital tunnel, tracing the ulnar nerve behind the medial epicondyle; the exposure then merges with the medial (Hotchkiss) approach to the elbow for coronoid, medial collateral ligament and ulnar nerve transposition work. For complex injuries requiring circumferential humeral access, pair the medial approach with an anterolateral or posterior approach through separate incisions, and for concurrent vascular injury plan the incision jointly with the vascular surgeon so a single extensile corridor exposes both the brachial artery and the humerus. Closure. Achieve meticulous haemostasis, particularly around the venous and arterial branches. Re-approximate the deep fascia loosely over the intermuscular septum only if it does not compress the neurovascular bundle. Close subcutaneous tissue and skin in layers and consider a drain for large dead space. Document the position and status of the brachial artery, median nerve and ulnar nerve in the operative note, and apply a splint appropriate to the procedure performed. Nerve injury management:

• If a nerve is found transected intra-operatively: primary repair or grafting by an appropriate specialist
• If a neurapraxia is suspected post-operatively: document the deficit, remove constricting dressings, obtain EMG and nerve conduction studies at three to four weeks
• Consider exploration if there is no clinical or electrical recovery by three months
• For permanent ulnar or median deficits, consider nerve grafting or appropriate tendon transfers

Post-operative care. Document distal neurovascular status, comparing with the pre-operative baseline, and specifically test ulnar and median nerve function and distal pulses; splint or sling appropriate to the procedure and elevate the limb. For nerve work, begin early protected range of motion to prevent adhesions; for vascular repair, monitor perfusion closely and use antiplatelet or anticoagulation per the vascular protocol; for bone work, immobilise then progress loading guided by healing. Functional outcome depends on the underlying pathology and the integrity of the neurovascular structures.

Guidelines, Registries & Global Practice The medial approach to the arm and distal humerus is a classical Henry exposure taught and examined worldwide across advanced orthopaedic practice, DNB/MS, MRCS and SICOT systems. Its principles - supine positioning, a true brachialis-triceps internervous plane along the medial intermuscular septum, and systematic protection of the brachial artery, median nerve, ulnar nerve, basilic vein and medial antebrachial cutaneous nerve - are consistent internationally.

Population and clinical evidence:

• Humeral shaft fractures have an incidence of roughly 12 to 15 per 100,000 per year, and the majority unite with functional bracing.
• Pulseless supracondylar fractures are most often associated with a kinked or in-spasm intact artery rather than transection; formal vascular repair is required in a minority.
• Ulnar neuropathy at the elbow is the second most common upper-limb compressive neuropathy, and surgical technique selection remains individualised. Global practice variation. In high-resource centres, dedicated vascular repair and microsurgical nerve reconstruction are immediately available, and small-fragment pre-contoured medial plates support limited fixation. In resource-limited settings, the same anatomical principles apply with standard small-fragment implants; non-operative bracing has a correspondingly larger role for shaft fractures, and brachial artery repair may rely on vein graft and limited instrumentation. Consent (globally applicable): discuss injury to the ulnar or median nerve (variable incidence, mostly transient), injury to the medial antebrachial cutaneous nerve with possible painful neuroma, bleeding from the basilic vein or brachial artery, infection (1 to 3 percent), haematoma, and stiffness if the elbow is incorporated.