Humeral Shaft Fracture: Optimal Treatment & Orthopedic Board Prep MCQs
Key Takeaway
For most closed, stable humeral shaft fractures, non-operative management using a functional brace, like a Sarmiento brace, is the gold standard. This approach achieves over 90% union rates. Initial treatment often involves coaptation splinting, followed by a functional brace once swelling reduces, provided angulation and shortening are within acceptable limits.
A 45-year-old male sustains a closed, mid-shaft humeral fracture. You are presented with the following radiograph. The patient has intact sensation and power in the radial nerve distribution. What are the indications for surgery, and how would you manage this patient?
Candidate: "This is a closed mid-shaft humeral fracture. I would manage this non-operatively with a functional brace, provided the alignment is acceptable. Acceptable criteria are <20 degrees of angulation and <3cm of shortening. Surgery is indicated for absolute reasons like open fractures, floating elbow, vascular injury, or compartment syndrome, or relative reasons like failure of conservative management."
Candidates often fail to mention the timing of radial nerve assessment or conflate "absolute" versus "relative" indications. They may also neglect to describe the specific clinical examination needed to confirm neurovascular integrity before deciding on non-operative management.
A high-scoring answer structures the response by: 1) Defining the fracture characteristics. 2) Stating the management goal (functional bracing is the gold standard for closed, stable fractures). 3) Explicitly listing the "absolute" surgical indications (Open, vascular compromise, compartment syndrome, floating elbow, pathological). 4) Addressing the Radial Nerve: Mentioning that a primary palsy is NOT an indication for immediate surgery unless the fracture itself requires ORIF (observation for 3 months), whereas an iatrogenic palsy after manipulation/surgery IS an indication for exploration.
Suppose you opt for ORIF with a plate. During your approach, you are concerned about the radial nerve. What are the specific risk zones for the radial nerve in the posterior approach, and how do you protect it?
Candidate: "The radial nerve runs in the spiral groove. In a posterior approach, I would identify it proximal to the fracture site and trace it distal to the lateral intermuscular septum. I protect it by gently mobilizing it with a vessel loop."
Failing to mention the anatomical proximity to the lateral intermuscular septum or the specific "10-14cm" rule from the lateral epicondyle. Candidates often fail to emphasize that if the nerve is not seen, it is not safe.
The candidate should state: "The radial nerve exits the spiral groove through the lateral intermuscular septum approximately 10–14 cm proximal to the lateral epicondyle. During the posterior approach, the nerve must be identified and visualized before any retraction or instrumentation. Once identified, it is protected with a wet vessel loop. If the fracture is in the distal third, the nerve is at high risk as it crosses the posterior to lateral border."
