The suprascapular nerve is a nerve in the upper limb that provides both sensory and motor functions. It plays a crucial role in the shoulder's functionality.
Functions of the Suprascapular Nerve
The suprascapular nerve has two primary types of functions:
Sensory Function
- It provides sensory innervation to the acromioclavicular joint and the glenohumeral joint. This means it transmits information about pain, pressure, and position from these joints back to the brain.
Motor Function
- It controls the muscles that are vital for shoulder movement. Specifically, the suprascapular nerve innervates the:
- Supraspinatus muscle, which helps in the initial abduction (lifting away from the body) of the arm.
- Infraspinatus muscle, which is responsible for external rotation of the arm.
Summary of Suprascapular Nerve Functions
| Function | Targeted Area/Muscle | Purpose |
|---|---|---|
| Sensory | Acromioclavicular and Glenohumeral Joints | Provides sensory feedback (pain, pressure, position) from the shoulder joints. |
| Motor | Supraspinatus Muscle | Assists in arm abduction |
| Infraspinatus Muscle | Helps with external rotation of the arm |
Clinical Significance
Damage to the suprascapular nerve can cause various issues, including:
- Shoulder Pain: Sensory damage can lead to chronic pain in the shoulder region.
- Muscle Weakness: Impaired motor function results in weakness or paralysis of the supraspinatus and infraspinatus muscles, leading to difficulty in arm abduction and external rotation.
- Atrophy: Over time, muscle damage may cause these muscles to waste away or atrophy.
Potential Issues & Examples
- Nerve Entrapment: The suprascapular nerve can become compressed or trapped in the suprascapular notch, causing pain, weakness, and dysfunction.
- Sports Injuries: Athletes, particularly those involved in overhead activities, are at risk of injuring this nerve.
- Trauma: Direct trauma to the shoulder can also cause injury to this nerve.
