Shoulder injuries
Check the axillary nerve before and after any reduction. Look closely at the skin over a broken collarbone.
A 28-year-old fell onto his outstretched arm playing cricket. The shoulder looks squared off and he holds the arm away from his body, slightly turned out, supporting it with the other hand. He can't feel a patch on the outer upper arm.
An hour later, a 40-year-old man is brought in after an electric shock at work. He holds his arm across his body, turned in, and can't turn it outwards. The AP X-ray is reported as "no dislocation".
What does each have, and what must you document before reducing?
- Check and document nerves before reductionAxillary nerve: sensation over the "regimental badge" area and deltoid contraction. Also radial, median, ulnar.
- Check pulsesBrachial artery injury, especially in older patients.
- X-ray before reductionAP plus a Y or axillary view. Look for fractures.
- AnalgesiaEntonox, IV opioid titrated, or an intra-articular block.
- ReduceGentle external rotation or other unit techniques. Never force.
- After reductionRecheck nerves and pulses, X-ray, broad arm sling.
- Follow-upFracture or shoulder clinic. Young first dislocators recur often.
- Neurovascular deficit
- Fracture-dislocation
- Failed reduction (stop after 2 attempts)
- Skin tenting over a clavicle fracture
- Posterior dislocation
- Open injury
- Posterior dislocation
- Axillary nerve injury
- Greater tuberosity or humeral neck fracture
- Rotator cuff tear in older patients
- Brachial plexus injury
- Cardiac or diaphragmatic pain called "shoulder strain"
| Anterior dislocation | Over 95% of shoulder dislocations, arm held away and externally rotated |
| Posterior dislocation | After fits or electric shock, arm held internally rotated, easily missed on AP view |
| Axillary nerve | Sensation over the lower deltoid ("regimental badge") |
| Morphine | 2.5–5 mg IV titrated |
| Intra-articular lidocaine 1% | Up to 20 mL (within max dose) per unit protocol |
| Over 40 with dislocation | Rotator cuff tear common, review strength at follow-up |
Check every dose against a current drug reference and your hospital protocol.
On this page
History
- Mechanism: fall onto the arm or shoulder, sports, fit or electric shock (posterior dislocation), road accident.
- Previous dislocations (recurrence common in young people).
- Numbness, weakness, cold hand.
- Age: older patients more often have fractures and cuff tears.
- Left shoulder pain without injury: think heart (MI), and right shoulder tip pain: think gallbladder or diaphragm.
Examination
- Look: squared-off shoulder (anterior dislocation), step at the top (ACJ), deformity over the clavicle, skin tenting, bruising down the arm (humerus fracture).
- Feel: clavicle, ACJ, humeral head, greater tuberosity, humeral shaft.
- Move: don't force movement in obvious dislocation.
- Nerves: axillary (regimental badge sensation, deltoid), radial, median, ulnar, musculocutaneous.
- Pulses: radial, capillary refill.
Which injury?
Anterior dislocation
Posterior dislocation
Clavicle fracture
ACJ injury
Proximal humerus fracture
| Injury | Clues | X-ray |
|---|---|---|
| Anterior dislocation | Squared shoulder, arm externally rotated | Humeral head below and in front of the glenoid |
| Posterior dislocation | After fit or electric shock, arm internally rotated, can't externally rotate | "Light bulb" humeral head on AP; clear on Y or axillary view |
| Clavicle fracture | Tender deformity, usually middle third | Clavicle view |
| ACJ injury | Step at the top | Widened ACJ |
| Proximal humerus fracture | Older, bruising, pain | Surgical neck or tuberosity fractures |
| Rotator cuff tear | Over 40, weak abduction, painful arc | Usually normal; ultrasound later |
A single AP view can miss a posterior dislocation. Always get a second view (Y or axillary).
Reducing an anterior dislocation
- Consent and analgesiaEntonox, IV opioid, or intra-articular lidocaine; procedural sedation only by trained staff.
- External rotation methodArm by the side, elbow at 90°, slowly rotate outward over a few minutes; often reduces without force.
- AlternativesCunningham massage, scapular manipulation, traction-countertraction.
- Stop ifTwo failed attempts, fracture-dislocation, or nerve deficit: orthopaedics.
- ConfirmPain relief, normal contour, recheck nerves and pulse, post-reduction X-ray, broad arm sling.
Clavicle and ACJ
- Middle-third clavicle fracture with intact skin: broad arm sling for comfort, analgesia, early pendulum exercises, fracture clinic. Most heal well.
- Skin tented, white or broken, or neurovascular problems: orthopaedics urgently.
- ACJ injury: sling and analgesia; displaced types to orthopaedics.
Proximal humerus fracture
Common in older people with osteoporosis. Collar and cuff, analgesia, early pendulum exercises when comfortable, fracture clinic. Displaced or fracture-dislocations need orthopaedics. Check the axillary nerve.
Treatment doses
Common mistakes
- Not documenting nerves before reduction.
- Missing a posterior dislocation on a single AP view.
- Using force or repeated attempts.
- Missing a greater tuberosity fracture on the pre-reduction film.
- Calling left shoulder pain a strain without thinking of the heart.
- Leaving an older patient in a sling too long (stiff shoulder).
Follow-up
- First dislocation in a young person: shoulder or fracture clinic (high recurrence; may need surgery).
- Sling for comfort; early movement as advised to prevent stiffness.
- Over 40: check rotator cuff strength at follow-up.
Frequently asked questions
Which nerve is injured in shoulder dislocation?
The axillary nerve: numbness over the lower part of the deltoid ("regimental badge" area) and weak deltoid. Check and document before and after reduction.
How is a posterior shoulder dislocation recognised?
After a fit or electric shock, the arm is held internally rotated and can't be turned outwards. The AP X-ray may show a "light bulb" humeral head; a Y or axillary view confirms it.
How is a clavicle fracture treated?
Most middle-third fractures heal in a broad arm sling with analgesia and early movement. Skin tenting, open fractures and neurovascular problems need orthopaedics.
How is an anterior shoulder dislocation reduced?
After analgesia, gentle external rotation with the elbow at 90° often reduces it. Other techniques include Cunningham massage and scapular manipulation. Check nerves and X-ray afterwards.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. Before reducing an anterior shoulder dislocation, which nerve must be checked?
Answer: Axillary nerve. Check and document sensation over the lateral deltoid before and after reduction.
- Radial nerve only: Axillary is most commonly injured.
- Phrenic nerve: No.
- Long thoracic nerve: No.
- Median nerve only: Less common.
2. After an electric shock, a man holds his arm internally rotated and can't rotate it outwards. What is likely?
Answer: Posterior dislocation. Posterior dislocations follow fits or electric shocks.
- Frozen shoulder: Not acute.
- Rotator cuff tendinitis: No.
- Anterior dislocation: Arm is externally rotated.
- Clavicle fracture: No.
3. A clavicle fracture is tenting the skin. What is the management?
Answer: Urgent orthopaedic review. Skin tenting can break the skin; reduce or fix urgently.
- Figure-of-eight bandage only: Not enough.
- No treatment: No.
- Physiotherapy: No.
- Sling and routine clinic: Tenting risks an open fracture.
4. A rugby player dislocates his shoulder anteriorly. After reduction, he has numbness over the ‘regimental badge’ area. Which nerve is injured?
Answer: Axillary nerve. Anterior dislocation (95%) — arm abducted and externally rotated; flattened shoulder contour. Check axillary nerve (sensation over deltoid ‘badge’ area, deltoid power) before and after reduction. X-ray before (exclude fracture) and after reduction. Hill–Sachs (humeral head) and Bankart (glenoid labrum) lesions predispose to recurrence. Posterior dislocation: seizures/electric shock, ‘light bulb’ sign.
- Radial nerve: Radial nerve injury causes wrist drop.
- Musculocutaneous nerve: Musculocutaneous injury causes lateral forearm numbness.
- Long thoracic nerve: Long thoracic nerve injury causes a winged scapula.
5. A 20-year-old fell off a bike and has a closed midshaft clavicle fracture with minimal displacement; skin and neurovascular status are intact. What is the treatment?
Answer: Broad arm sling + early mobilisation. Midshaft clavicle fractures (commonest) usually heal with a sling for comfort for 1–2 weeks and early mobilisation. Surgical fixation for open fractures, skin tenting, neurovascular injury, floating shoulder, significant shortening/displacement (> 2 cm) in active patients, or non-union. Lateral-third displaced fractures have higher non-union rates.
- ORIF for all: ORIF is not needed for minimally displaced fractures.
- Figure-of-eight bandage strictly: A figure-of-eight bandage gives no advantage.
- Immobilise for 12 weeks: Twelve weeks causes stiffness.
6. Which rotator cuff muscle starts abduction of the arm and is most often torn?
Answer: Supraspinatus. The rotator cuff muscles are supraspinatus, infraspinatus, teres minor and subscapularis (SITS). Supraspinatus starts abduction (first 15°) and its tendon passes under the acromion, where it is often impinged or torn. Teres major is not part of the cuff.
- Infraspinatus: Lateral rotation.
- Teres minor: Lateral rotation.
- Subscapularis: Medial rotation.
- Teres major: Not a rotator cuff muscle.
7. During a difficult breech delivery, the baby's arm is pulled upwards. Later the baby has a claw hand with wasting of the small hand muscles and a Horner's syndrome on that side. Which part of the brachial plexus is injured?
Answer: Lower trunk (C8–T1): Klumpke's palsy. Forced abduction of the arm (breech delivery, grabbing a branch while falling) tears the lower trunk (C8–T1). This paralyses the intrinsic hand muscles (claw hand) and loses sensation on the medial forearm and hand. Injury to T1 near the cord can include sympathetic fibres, causing Horner's syndrome. Erb's palsy (C5–C6) gives the 'waiter's tip' position.
- Upper trunk (C5–C6): Erb's palsy: Waiter's tip: arm adducted, internally rotated, elbow extended.
- Posterior cord: Wrist drop and weak shoulder.
- Lateral cord: Weak elbow flexion and lateral forearm numbness.
- Long thoracic nerve: Winged scapula.
References and dose sources
- NICE NG38 — Fractures (non-complex)
- BOAST — Shoulder dislocation
- Morphine dosing: Drugs.com: Morphine dosage (see also our morphine dose page)
- Lidocaine (lignocaine) dosing: Drugs.com: Lidocaine dosage (see also our lidocaine (lignocaine) dose page)
- Paracetamol dosing: Drugs.com: Acetaminophen (paracetamol) dosage (see also our paracetamol dose page)
- Ibuprofen dosing: Drugs.com: Ibuprofen dosage (see also our ibuprofen dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.