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Chronic Shoulder Pain

Spotlight on Dr. Benjamin DuBois and Reverse Total Shoulder Replacement

Posted on: July 29th, 2021 by Our Team

What is a Reverse Total Shoulder Replacement?

A traditional shoulder replacement (known as an Anatomic Total Shoulder Arthroplasty) is typically performed on a patient who has end-stage osteoarthritis of the shoulder, or are what we call “bone-on-bone.” In this procedure the humeral head (ball) and the glenoid (socket) are replaced with a cobalt chrome ball and a plastic socket. Instead of your shoulder grinding bone on bone your shoulder will glide smoothly with metal on plastic. The procedure is actually pretty similar to a hip replacement when you think about it.

In an Anatomic Total Shoulder Arthroplasty (TSA) we are keeping the anatomy the same as your native anatomy. The ball is still the ball and the socket is still the socket but just replaced for metal and plastic parts. So, what makes the Reverse Total Shoulder Arthroplasty different you ask? Well, it’s in the name. The anatomy is reversed. Instead of having a metal ball replacing your native humeral head that will be switched to a plastic socket. Similarly, in place of your native socket you will instead have a metal ball. So, now the ball and socket are switched or….reversed, hence the name Reverse Total Shoulder Arthroplasty.

Why are the indications for a Reverse Total Shoulder Arthroplasty?

In order to have a successful Anatomic TSA you need to have two very important things. First, it is imperative to have an intact rotator cuff. The Anatomic TSA relies heavily on the function of the supraspinatus (one of the main rotator cuff tendons). This muscle and tendon are mainly responsible for helping to raise the arm away from the body. This tendon originates from the top of the shoulder blade and attaches to the humeral head. If this tendon is torn completely, it will be extremely difficult to perform this movement. The supraspinatus also occupies the space between the humeral head and the acromion (the bone that creates the roof of the shoulder joint). If this tendon no longer occupies this space the ball will ride up and hit the acromion which will prohibit the motion of raising the arm.

The Reverse TSA has found a way to solve this problem. With the ball and socket reversed, there is no possible way that the ball can ride up into the acromion anymore. With the anatomy reversed the physics of the shoulder joint has changed. You no longer require the use of the supraspinatus to produce that arm motion. Instead, the deltoid muscle will be used primarily to power this movement.

In addition to an intact rotator cuff, the second thing needed is enough glenoid bone stock for the plastic socket to attach onto. A reverse TSA is usually the right choice for a patient who has an intact rotator cuff but has significant glenoid (socket) bone loss. The reason for this is because the glenoid component of the Reverse TSA uses a metal base plate with 5 metal screws that anchor securely into the socket. The traditional anatomic Total Shoulder Replacement the glenoid component is made of a polyethylene plastic with plastic pegs that are cemented into the socket. If there is not enough bony material to adhere to, this method does not work well. This can be the case for some of the most severe cases of osteoarthritis of the shoulder where the ball actually starts to erode away the socket.

Why Choose Dr. Benjamin DuBois?

It’s simple, because experience matters! Dr. Benjamin DuBois is a Superspecialist in this exact procedure. The FDA approved this device in 2004 and Dr. DuBois performed the very first Reverse TSA surgery in San Diego County that same year. He has been perfecting his skills with this surgery ever since. He is the only surgeon in San Diego who does nothing but shoulder surgery with about half of his surgical cases consisting of shoulder joint replacement procedures. He has done over 1,000 Reverse Total Shoulder Replacements, averaging over 100 per year.

Considering his expertise in this area, Dr. DuBois was asked to be part of the design team for Donjoy Orthopedics (DJO) for the latest generation of the Reverse TSA in 2011. This model made it’s way onto the market in 2015. It is still the same implant that Dr. DuBois utilizes today! Dr. DuBois performs these operations weekly at Sharp Grossmont Hospital and University Ambulatory Surgery Center. Call our office at (619) 462-3131 or visit our website to make an appointment with our highly skilled shoulder specialist today for a consultation.