Overview

The suprascapular nerve is a small but important nerve that supplies two of your four rotator cuff muscles — the supraspinatus and infraspinatus. It travels a twisting path through two narrow bony tunnels on the shoulder blade, which makes it more vulnerable to getting pinched or compressed than most other nerves in the shoulder. When this happens, it can cause deep shoulder pain, weakness, and sometimes visible muscle wasting, especially in people who do a lot of overhead activity.

Location

Branches off the upper trunk of the brachial plexus (the network of nerves supplying the arm), carrying fibers mainly from the C5 and C6 spinal nerve roots
Travels behind the collarbone and across the top of the shoulder blade
Passes through the suprascapular notch, a groove in the top of the shoulder blade covered by a ligament (forming a tunnel), before reaching the supraspinatus muscle
Continues through a second narrow passage, the spinoglenoid notch, before reaching the infraspinatus muscle

Function

Provides motor (movement) signals to the supraspinatus and infraspinatus muscles, both part of the rotator cuff
Carries sensory signals from the shoulder socket joint and the acromioclavicular joint, contributing to your awareness of deep shoulder position and pain
Contributes sensory fibers to the subacromial bursa and some shoulder ligaments

In plain English: this nerve is the "wiring" that tells your supraspinatus (which starts arm-raising) and infraspinatus (which turns your arm outward) muscles when to fire — without it working properly, those two muscles weaken even though they're otherwise perfectly healthy (Radiopaedia: Suprascapular nerve).

Structures It Connects To

Brachial plexus — its origin, specifically the upper trunk
Suprascapular notch — a bony groove on the scapula that the nerve passes through, alongside its own artery and vein
Supraspinatus muscle — receives motor branches from this nerve
Spinoglenoid notch — a second bony passage further along the nerve's path
Infraspinatus muscle — receives motor branches from this nerve after it passes the spinoglenoid notch
Glenohumeral and acromioclavicular joints — receive sensory branches from this nerve

Movements It Assists

Shoulder abduction (raising the arm out to the side) — via its supply to the supraspinatus
External rotation of the arm — via its supply to the infraspinatus
Contributes indirectly to overall shoulder joint stability, since both muscles it supplies are part of the rotator cuff's stabilizing team

Common Injuries

Suprascapular nerve entrapment/compression — most often at the suprascapular notch (affecting both supraspinatus and infraspinatus) or the spinoglenoid notch (affecting only infraspinatus), sometimes caused by cysts, repetitive overhead motion, or anatomical variations (PMC: Suprascapular Nerve Pathology)
Can contribute to or complicate the picture of rotator cuff tear, since nerve-related weakness can look similar to tendon tear weakness
Traction injury — can occur alongside significant shoulder trauma or dislocation

Pain Referral Patterns

Pain from suprascapular nerve issues is typically felt as a deep, dull ache at the back or top of the shoulder, often poorly localized
Compression at the spinoglenoid notch specifically can sometimes cause weakness without much pain at all
Overhead athletes, particularly volleyball players, sometimes notice gradual weakness in outward arm rotation with minimal pain, a pattern that raises suspicion for this specific nerve issue

Clinical Relevance

Because suprascapular nerve compression can closely mimic a rotator cuff tear — both cause weakness in similar movements — clinicians use imaging (MRI or ultrasound) and sometimes nerve conduction studies to tell the two apart (PMC: Suprascapular Nerve Pathology). This distinction is clinically important because nerve compression, when caused by a cyst or other structural issue, may need a different treatment approach than a torn tendon. Suprascapular nerve blocks are also sometimes used clinically to manage shoulder pain, since this nerve carries a large share of the joint's sensory signals.

Interesting Facts

Suprascapular nerve dysfunction is thought to contribute to shoulder pain in as many as one-third of overhead athletes with shoulder pain, according to some estimates, despite being a relatively obscure nerve to most people (StatPearls: Suprascapular Nerve Injury).
The suprascapular notch comes in several different shapes across the population — some people have a shallow groove while others have a nearly enclosed tunnel — and this variation can affect how likely someone is to develop nerve compression here.
This nerve is unusual in that it has almost no role in skin sensation (unlike most peripheral nerves) — its main jobs are muscle control and deep joint sensation, not surface touch.

Supraspinatus — supplied by this nerve
Infraspinatus — supplied by this nerve
Scapula — contains the suprascapular and spinoglenoid notches this nerve passes through
Brachial plexus (shoulder overview) — the nerve network this nerve branches from
Glenohumeral joint — receives sensory branches from this nerve

References

StatPearls (NCBI Bookshelf). "Anatomy, Shoulder and Upper Limb, Suprascapular Nerve." https://www.ncbi.nlm.nih.gov/books/NBK557880/
StatPearls (Point of Care). "Suprascapular Nerve Injury." https://www.statpearls.com/point-of-care/29748
PMC (The Open Orthopaedics Journal). "Suprascapular Nerve Pathology: A Review of the Literature." https://pmc.ncbi.nlm.nih.gov/articles/PMC5366386/
Radiopaedia. "Suprascapular nerve." https://radiopaedia.org/articles/suprascapular-nerve
Physiopedia. "Suprascapular Nerve." https://www.physio-pedia.com/Suprascapular_Nerve

Suprascapular Nerve