Comprehensive guide to the anterior (Henry) approach to the humeral shaft for ORIF of mid/distal humerus fractures with emphasis on radial nerve protection
Reviewed by OrthoVellum Editorial Team
Orthopaedic clinicians and medical editors • Published by OrthoVellum Medical Education Team
Brachialis Split | Radial Nerve at 14cm from LE | Holstein-Lewis 18% Risk
Most vulnerable structure: The radial nerve crosses from posterior to lateral humerus at the spiral groove (mean 14.2cm proximal to lateral epicondyle, range 10-17cm - Gerwin 1996). At this location, the nerve is firmly adherent to bone via the lateral intermuscular septum and cannot be easily mobilized. This zone of adherence creates highest injury risk during fracture fixation.
Distal 1/3 spiral fracture where the radial nerve crosses the spiral groove AT the fracture site. Highest iatrogenic injury risk: 18% (vs 2-5% for standard mid-shaft fractures - Ring 1999). The spiral fracture line crosses the nerve precisely where it adheres to bone. MUST identify nerve at lateral intermuscular septum BEFORE fracture manipulation to reduce injury risk.
Three key techniques: (1) Proximal-to-distal exposure - encounter nerve predictably if it crosses surgical field. (2) Subperiosteal dissection ONLY - never dissect posteriorly around spiral groove. (3) For Holstein-Lewis: Identify nerve at lateral intermuscular septum before reducing fracture. Use vessel loop for gentle protection during reduction.
CRITICAL distinction: Immediate post-op palsy (pre-op intact) = iatrogenic injury → urgent re-exploration within 24-48 hours for neurolysis or repair. Primary fracture palsy (at injury) = observe 3-4 months (70% spontaneous recovery - Shao 2005). Serial EMG at 6-8 weeks shows reinnervation. Explore only if no recovery by 4-6 months.
Memory Hook:HUMERUS approach: Henry's plane splits brachialis to access middle/distal shaft while protecting the radial nerve 14cm from LE!
Memory Hook:HOLSTEIN-Lewis carries the HIGHEST radial nerve injury risk - identify the nerve BEFORE touching the fracture!
Memory Hook:RADIAL nerve protection: Route posterior to lateral, Adherent to bone, Don't explore routinely, Identify if high-risk, Approach proximal-to-distal, anteraLateral plate!
The anterior approach to the humeral shaft (also known as the Henry approach or anterolateral approach) provides direct access to the middle and distal 1/3 of the humerus for fracture fixation, nonunion repair, and tumor excision. First described by Henry in 1945, this approach has become the most commonly used surgical corridor for humeral shaft fractures requiring operative fixation.
Historical evolution:
Modern applications:
Approach Selection
The anterior approach is best for middle and distal 1/3 humeral shaft fractures. For proximal 1/3 fractures (above deltoid insertion), use the deltopectoral approach for better proximal exposure. For mid-shaft at spiral groove, consider the posterior approach for direct radial nerve visualization (lower iatrogenic injury risk 1-3% vs 2-5%).
The anterior approach utilizes an internervous plane with brachialis muscle splitting:
Primary Interval:
Critical concept: This is NOT a "pure" internervous plane (like Thompson or Henry radius approaches) because brachialis must be SPLIT to access humerus. However, splitting in the midline respects the dual innervation and minimizes denervation.
1. RADIAL NERVE (PRIMARY HAZARD):
Anatomic Course:
Surgical Importance:
Protection Strategy:
2. BRACHIAL ARTERY:
Anatomic Course:
Protection:
3. MEDIAN NERVE:
Anatomic Course:
Protection:
4. MUSCULOCUTANEOUS NERVE:
Anatomic Course:
Surgical Relevance:
ABSOLUTE INDICATIONS FOR OPERATIVE FIXATION:
RELATIVE INDICATIONS (Operative vs Non-Operative Decision):
NON-OPERATIVE MANAGEMENT (Functional Bracing - STILL FIRST-LINE):
Sarmiento functional bracing remains GOLD STANDARD for closed, isolated humeral shaft fractures with acceptable alignment:
| Factor | Anterior Approach | Posterior Approach | Preferred |
|---|---|---|---|
| Fracture Location | Middle/distal 1/3 shaft (below deltoid insertion) | Mid-shaft at spiral groove level | Depends on fracture location |
| Radial Nerve Visualization | NOT routinely visualized - outside surgical field | DIRECTLY VISUALIZED - exposed in triceps-splitting field | Posterior (direct visualization) |
| Iatrogenic Nerve Injury Risk | 2-18% (standard 2-5%, Holstein-Lewis 18% - Ring 1999) | 1-3% (McKee 2004) | Posterior (lower injury risk) |
| Patient Positioning | Supine (familiar, polytrauma-friendly) | Prone/lateral decubitus (unfamiliar, difficult for polytrauma) | Anterior (supine positioning easier) |
| Muscle Handling | Brachialis splitting (minimal denervation, no triceps weakness) | Triceps splitting or TRAP (10-15% weakness, 5% with TRAP) | Anterior (less invasive) |
| Plate Biomechanics | Anterolateral (tension side - optimal) | Posterior (compression side - suboptimal) | Anterior (better biomechanics) |
Patient Position:
Equipment:
Anesthesia:
1. RADIAL NERVE INJURY (2-18%):
Mechanism:
Prevention:
Recognition:
Management:
Outcome:
1. NONUNION (5-8%):
Risk Factors:
Management:
2. INFECTION (2-3%):
Management:
3. SHOULDER STIFFNESS (10-15%):
Prevention:
Management:
Practice these scenarios to excel in your viva examination
"A 45-year-old male sustains a closed mid-shaft humerus fracture after a fall. X-rays show a transverse fracture at the junction of middle and distal 1/3 with 15° varus angulation, 20° anterior angulation, and 1cm shortening. Radial nerve function is intact clinically. What are the indications for operative vs non-operative management? How would you manage this patient?"
"A 32-year-old female sustains a distal 1/3 spiral humeral shaft fracture (Holstein-Lewis pattern) in an MVA. Radial nerve function is INTACT clinically (normal wrist/finger extension, sensation over dorsal hand). X-rays show unacceptable alignment with 25° varus angulation. You decide to proceed with ORIF via anterior approach. Describe your surgical strategy to protect the radial nerve. What is the iatrogenic injury risk?"
"A 50-year-old male sustains a mid-shaft humerus fracture at the level of the spiral groove with 30° anterior angulation. Radial nerve function is intact. You decide to proceed with operative fixation. Compare the anterior vs posterior approach for this fracture. Which would you choose and why?"
High-Yield Exam Summary
Dabezies EJ, Banta CJ 2nd, Murphy CP, d'Ambrosia RD. Plate fixation of the humeral shaft for acute fractures, with and without radial nerve injuries. J Orthop Trauma. 1984;6(1):10-13.
Gerwin M, Hotchkiss RN, Weiland AJ. Alternative operative exposures of the posterior aspect of the humeral diaphysis with reference to the radial nerve. J Bone Joint Surg Am. 1996;78(11):1690-1695.
Shao YC, Harwood P, Grotz MR, Limb D, Giannoudis PV. Radial nerve palsy associated with fractures of the shaft of the humerus: a systematic review. J Bone Joint Surg Br. 2005;87(12):1647-1652.
Ring D, Chin K, Jupiter JB. Radial nerve palsy associated with high-energy humeral shaft fractures. J Hand Surg Am. 1999;24(4):683-688.
Bhandari M, Devereaux PJ, McKee MD, Schemitsch EH. Compression plating versus intramedullary nailing of humeral shaft fractures--a meta-analysis. Acta Orthop. 2006;77(2):279-284.
Sarmiento A, Zagorski JB, Zych GA, Latta LL, Capps CA. Functional bracing for the treatment of fractures of the humeral diaphysis. J Bone Joint Surg Am. 2000;82(4):478-486.
McKee MD, Miranda MA, Riemer BL, et al. Management of humeral shaft fractures in the geriatric patient. J Orthop Trauma. 2004;18(9):549-554.
Rüedi TP, Buckley RE, Moran CG. AO Principles of Fracture Management. 2nd ed. Stuttgart: Thieme; 2007.