Upper limb

Scapula

Before you say anything

A flat triangular bone that students identify instantly and then orient badly. Everything follows from one fact: the spine and acromion are on the back. Once you have the dorsal surface facing away from you, the glenoid cavity points laterally and the coracoid points forwards, and the side answers itself.

Which side? Three checks

Hold it like this first: Hold it against the back of the chest with the glenoid cavity directed laterally, forwards and slightly upwards, the coracoid process pointing forwards, and the spine on the surface facing backwards.

Check 1 — Find the spine
A prominent shelf of bone ending in the acromion lies on one surface only
That surface is dorsal and must face backwards
Check 2 — Find the glenoid cavity
A shallow pear-shaped articular hollow at one angle
It is the lateral angle, so it points to the side the bone belongs to
Check 3 — Find the coracoid process
A hooked process arising near the glenoid and curving forwards and laterally
It confirms which way is forwards once the spine is already facing back

Drill this against the clock →

Work it out, one rung at a time

Answer each question in your head first. Then open it.

1
Identify
What is this?
2
Orient
Which surface faces backwards?
3
Side
Which side?
4
Landmarks
What can you point out?
5
Attachments
What is attached?
6
Applied
Why does it matter?

Landmarks to point out

Spine
Across the upper dorsal surface
Divides the dorsal surface into supraspinous and infraspinous fossae and gives attachment to trapezius and deltoid.
Acromion
The lateral, expanded end of the spine
Forms the point of the shoulder and articulates with the clavicle.
Coracoid process
Arising from the upper border, hooking forwards and laterally
Gives attachment to pectoralis minor, coracobrachialis and the short head of biceps.
Glenoid cavity
Lateral angle
The shallow socket of the shoulder joint — its shallowness is why the joint is so mobile and so easily dislocated.
Supraglenoid tubercle
Just above the glenoid cavity
Origin of the long head of biceps brachii.
Infraglenoid tubercle
Just below the glenoid cavity
Origin of the long head of triceps brachii.
Suprascapular notch
Upper border, medial to the root of the coracoid
The suprascapular nerve passes beneath the superior transverse scapular ligament while the vessels pass above it.

Say these first

Flat and triangular with three borders and three angles
A spine ending in the acromion on the dorsal surface
A shallow glenoid cavity with a hooked coracoid beside it

Do not confuse it with

The hip bone
The hip bone's socket, the acetabulum, is deep and cup-shaped and is pierced by a notch; the scapula's glenoid cavity is shallow and unbroken.

Examiner trap

Turning the bone so the spine faces you and then reading the glenoid side directly. The spine is dorsal, so holding it towards you reverses left and right.

Memory hook

Spine at the back, glenoid to the side, coracoid to the front.

Why it matters

Paralysis of serratus anterior after injury to the long thoracic nerve lets the medial border lift off the chest wall — a winged scapula.
At the suprascapular notch the nerve runs under the ligament and the vessels over it, so the notch is a site of nerve entrapment.
The scapula is protected by thick muscle on both surfaces, so a fracture implies considerable force and should prompt a search for other injuries.

Senior’s 30-second takeaway

Scapula — the whole bench in four lines. Read this on the way in.

If you see this: A flat triangular bone · A spine ending in the acromion · A shallow glenoid cavity beside a hooked coracoid
If asked to identify it: This is a scapula; the spine lies on the dorsal surface and the glenoid cavity at the lateral angle gives the side.
If asked one more: Three of the four rotator cuff muscles arise from its fossae; teres minor comes from the lateral border.
If asked why it matters: Long thoracic nerve injury paralyses serratus anterior and produces a winged scapula.

Then stop. Let the examiner ask the next question.

Scapula

Before you say anything

Which side? Three checks

Work it out, one rung at a time

Landmarks to point out

Senior’s 30-second takeaway

Attachments

Articulations

Ossification

Viva voce

See it in 3D

🩺 Before you say anything

Which side? Three checks

Work it out, one rung at a time

Landmarks to point out

Senior’s 30-second takeaway

Attachments

Articulations

Ossification

🎙️ Viva voce

See it in 3D

Before you say anything

Viva voce