As the season kicks off, we focus on a common shoulder rugby injury

As the new rugby season gets underway, specialists across the country brace themselves for an increase in shoulder-related injuries, including AC joint shoulder injuries.

Rugby is a notoriously tough, physical contact sport which puts the body through a significant amount of trauma. A study published last year in the Journal for Orthopaedic Sports Medicine, Arthroscopy and Knee Arthroplasty, evaluated injury risk in International Rugby Union, focusing on the Welsh National Team. The shoulder was found to have the highest injury incidence and suffered one-third of recurrent injuries. Shoulder dislocations were also found to result in the most days lost per injury.

The shoulder is a complex joint, composed of a number of different joints, bone groups, muscles, ligaments and tendons. It has the the greatest range of motion in the body and is susceptible to a number of different injuries and conditions. One of the most common injuries suffered by rugby players is injury to the acromioclavicular or AC joint.

What are AC joint shoulder injuries?

The AC joint is situated at the top of the shoulder, being the junction between the shoulder blade (acromion) and collar bone (clavicle). Due to its location, the joint is particularly susceptible to trauma during rugby, with separation and dislocation being the most common problem experienced. A direct hit to the joint can cause it to become separated, along with a fall onto an outstretched hand.

Understanding the different types of AC joint separation

Like many shoulder injuries, there are different classifications of separation that can occur in AC joint shoulder injuries. They are measured using the Rockwood scale:

Grade 1 – pain is experienced around the AC joint, but the bones remain in position.

Grade 2 – as well as pain around the joint, there is some damage to the capsule, as well as a partial tear in the superior ligament. A lump may also be visible through the skin.

Grade 3 – the coracoclarvicular and the AC ligaments are both ruptured, causing a large lump to be visible under the skin. A true separation occurs and the trapezius and deltoid will have been detached.

Grade 4 – the trapezius is ruptured due to the clavicle moving behind the joint. As with grade 3, the trapezius and deltoid are detached.

Grade 5 – similar to grade 3 injuries, though the separation is more severe. The clavicle punctures the above muscle and, as with grades 3 and 4, the trapezius and deltoid are detached.

Grade 6 – the least common injury, grade 6 sees the clavicle become hooked underneath the coracoid process after being pushed downwards. It ends up behind the coracobrachialis and biceps.

AC joint injuries: symptoms and prevention

Pain is the most notable symptom of AC joint shoulder injuries. This will be experienced towards the outer end of the collarbone. It will also likely feel tender to touch and be inflamed too. Once the injury has settled, the pain will be very localised and won’t radiate towards other parts of the body. You’ll likely notice the pain becomes worse with certain activities, such as lifting your arm above your head.

The symptoms are similar to a variety of collarbone and shoulder injuries. Therefore, a specialist diagnosis is required to ensure you receive the appropriate treatment.

If the ACJ is injured, then the lesser grade injuries can generally be treated without surgery, however, higher grade injuries may need an intervention. Recently, Mr Steve Corbett of the London Shoulder Specialists has presented both nationally and internationally on the decision making involved.

It’s very difficult to prevent AC joint shoulder injuries in rugby, as it is a contact sport with a high likelihood of knocks to the collarbone. Learning how you can stabilise the shoulder and also building up the muscles can help somewhat.

If you’re concerned that you may have an AC joint injury, book a consultation with London Shoulder Specialists at Fortius Clinic today. There are a number of treatment options available and our specialists are highly experienced in treating rugby injuries at every level of the sport.