The three main types at a glance

Illustrations are simplified and not to scale.

The key question: is your rotator cuff working?

The rotator cuff is a group of four tendons that hold the ball of the shoulder centred in the socket as you move your arm. A normal (anatomic) shoulder replacement relies on these tendons to work properly.

If the rotator cuff is badly torn or worn out, an anatomic replacement can’t stay centred. A reverse replacement solves this by changing the mechanics of the joint, so the large deltoid muscle over the shoulder can lift the arm instead.

Reverse shoulder replacement

A reverse replacement is the most common shoulder replacement in Australia. About three in four primary total shoulder replacements recorded by the Australian joint replacement registry are reverse replacements.¹

It is commonly recommended for:

• arthritis with a damaged or torn rotator cuff (cuff tear arthropathy)
• large rotator cuff tears that can no longer be repaired, especially when the arm can’t be lifted
• arthritis where the socket is badly worn or misshapen
• many complex fractures of the top of the arm bone in older people
• revision of a previous shoulder replacement

Reverse replacements are also used for arthritis when the rotator cuff is intact, particularly in older people. A large English registry study of people aged 60 and over with osteoarthritis and an intact rotator cuff found that reverse and anatomic replacements had similar shoulder function scores, complications and long-term revision rates. Reverse replacements had fewer reoperations in the first year.³

Read more about reverse shoulder replacement.

Dr Brumby-Rendell uses a bone-preserving mini reverse shoulder replacement, and reverse replacements can be performed with Mako robotic assistance at Eastwood Private Hospital.

Anatomic shoulder replacement

An anatomic replacement recreates the normal shape of the shoulder: a smooth metal ball on the arm bone and a new polyethylene surface on the socket. Because it works like a normal shoulder, it depends on a healthy rotator cuff.

It is mainly used for osteoarthritis when the rotator cuff is intact and the socket has enough good bone to support the new surface. A review of studies comparing anatomic and reverse replacements in this group found similar overall function scores, with anatomic replacements giving better external rotation (turning the arm outwards).²

Dr Brumby-Rendell uses a stemless anatomic implant. It is fixed in the top of the arm bone and has no long stem down the shaft, which preserves bone. Stemless implants were the most common type of anatomic shoulder replacement used in Australia in 2024.¹

Pyrocarbon hemiarthroplasty

In a hemiarthroplasty, only the ball of the shoulder is replaced and your own socket is kept. Traditionally the new ball was made of metal, and over time a metal ball can wear away the socket. Pyrocarbon is a carbon-based material with a stiffness much closer to bone, and it is designed to be gentler on the socket.

Because there is no plastic socket component to wear or loosen, pyrocarbon hemiarthroplasty is an option for some younger, active people with arthritis and a healthy rotator cuff.

• In a 2026 study of 103 pyrocarbon hemiarthroplasties in young, active patients (average age 56), 94% of shoulders had not needed revision at 5 years and 89% at 10 years. Of those still working before surgery, 92% returned to work.⁴
• In the Australian registry, pyrocarbon hemiarthroplasty has had revision rates similar to reverse and stemless anatomic replacements after the first six months.¹

The pyrocarbon head sits on a convertible stem. If the socket wears in later years, the shoulder can usually be converted to a total or reverse replacement without removing the stem.⁴ Results are best when the new ball is sized to match your own anatomy, which is one reason the operation is planned in 3D first.⁴

Shoulder replacement after a fracture

Some fractures of the top of the arm bone (proximal humerus) can’t be reliably fixed, particularly in older people with softer bone. Many of these fractures can be treated without surgery, but for badly displaced fractures a reverse shoulder replacement is increasingly used.

A 2026 randomised trial compared reverse shoulder replacement with non-surgical treatment in 80 people aged 60 to 90 with three- and four-part fractures. At one year, the reverse replacement group had better shoulder scores, less disability and could lift the arm higher (an average of 119° compared with 90°). Most fractures treated without surgery healed out of position.⁵

Dr Brumby-Rendell uses a reverse replacement with a stem designed specifically for fractures. He was the first surgeon in Australia to use this new fracture stem for proximal humerus fractures. See proximal humerus fractures.

What else guides the choice?

• Your rotator cuff – whether the tendons are intact and working.
• The shape of your socket – how much it has worn, and whether there is enough healthy bone to support a new surface.
• Your age and activity – what you want to do with your shoulder, and for how many years the replacement needs to last.
• Bone quality – particularly after a fracture.
• Previous surgery – including earlier rotator cuff repairs or stabilisation operations.
• Your goals – pain relief, range of movement, strength, and the activities that matter to you.

How the decision is made

At your consultation, Dr Brumby-Rendell examines your shoulder and reviews your X-rays. Sometimes an ultrasound or MRI is used to check the rotator cuff. Before surgery, a CT scan is used to build a 3D model of your shoulder and plan the size and position of the implant.

The recommendation is made with you, based on your shoulder and what you want from it. Whichever type you have, the operation uses the same minimally invasive approach and hospital pathway at Eastwood Private Hospital.

Frequently asked questions

Is a reverse shoulder replacement a second-best option?

No. A reverse replacement is designed for shoulders where the rotator cuff no longer works properly, and it is now the most common shoulder replacement in Australia. For arthritis with a healthy rotator cuff, large studies show reverse and anatomic replacements give similar overall results.³

Can a pyrocarbon hemiarthroplasty be converted later?

Yes. Pyrocarbon heads are used with a convertible stem, so if the socket wears in later years the shoulder can usually be converted to a total or reverse replacement without removing the stem.

Are all shoulder replacements done with the robot?

The Mako robotic system is currently used for reverse shoulder replacement. Every shoulder replacement is still planned in 3D from a CT scan.

What tests are needed to decide?

An examination and X-rays, plus a CT scan to plan the operation in 3D. Sometimes an ultrasound or MRI is used to assess the rotator cuff.

Do I need a referral?

Yes. A referral from your GP or another specialist is needed to claim a Medicare rebate for a specialist consultation. Once you have one, you can book online or call (08) 7077 0101.