## Median Nerve Course in the Forearm ### Correct Statements (Options 0, 1, 2) **Key Point:** The median nerve has a well-defined course with consistent anatomical landmarks. | Anatomical Feature | Details | | --- | --- | | **Entry into forearm** | Passes between the two heads (humeral and ulnar) of pronator teres | | **Anterior interosseous nerve (AIN)** | Terminal branch arising in proximal forearm, supplies deep flexors (FPL, FDP to digits 1–2, pronator quadratus) | | **Superficial flexor supply** | Flexor carpi radialis, palmaris longus, flexor digitorum superficialis (pronator teres also supplied) | ### Why Option 3 Is Wrong **High-Yield:** The median nerve crosses the wrist **DEEP to the flexor retinaculum** (within the carpal tunnel), not superficial to it. The recurrent motor branch (thenar branch) is a terminal branch in the palm, not a crossing structure at the wrist. **Clinical Pearl:** Carpal tunnel syndrome compresses the median nerve *within* the tunnel, beneath the retinaculum, causing sensory loss in the lateral 3.5 digits and motor loss in the thenar eminence and lumbricals of digits 1–2. **Warning:** Confusion arises because the palmaris longus tendon runs superficial to the flexor retinaculum; the median nerve itself lies deep to it. ### Median Nerve Branches Summary ```mermaid flowchart TD A["Median Nerve (Axilla)"]:::outcome --> B["Pronator Teres"]:::action A --> C["Flexor Carpi Radialis"]:::action A --> D["Palmaris Longus"]:::action A --> E["Flexor Digitorum Superficialis"]:::action A --> F["Anterior Interosseous Nerve"]:::outcome F --> G["Flexor Pollicis Longus"]:::action F --> H["Flexor Digitorum Profundus (Digits 1–2)"]:::action F --> I["Pronator Quadratus"]:::action A --> J["At Wrist: Deep to Flexor Retinaculum"]:::outcome J --> K["Recurrent Motor Branch (Thenar)"]:::action J --> L["Digital Sensory Branches"]:::action ``` [cite:Clinically Oriented Anatomy 8e Ch 6]
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.