SPORT INJURIES

Common sporting injuries of the shoulder include dislocations, Acromioclavicular joint (AC-JOINT) injuries, rotator cuff injuries, labral tears, thrower's shoulder, biceps injuries, bursitis and fractures. Dislocations and AC-JOINT injuries are more common in contact sports, such as rugby and wrestling, whilst rotator cuff tears and biceps lesions are common in sports involving explosive heavy weightlifting. Fractures around the shoulder are seen with sports involving crashes and falls from heights (of which there are many).

It is often quite difficult to adequately assess the severity of a shoulder injury and the structures damaged following sports injuries, as simple muscle strains look very similar to more serious injuries. Thus, early assessment from a skilled Shoulder Therapist or Surgeon is essential for early appropriate management. This may involve x-rays, and a special scan.

Causes of sports injuries to the shoulder

1. Injury to the shoulder joint

Common sporting injuries involving the shoulder:

• Shoulder dislocations

Because the shoulder joint is the most mobile joint in the body it is potentially unstable. It is therefore the most common joint to dislocate in the body. In some people only minor trauma can cause the shoulder to "pop out" of joint. If your shoulder does dislocate it needs to be 'put back' as soon as possible and you then require physiotherapy.

Over 50% of dislocations can recur, especially in young sports people. Repeated dislocations lead to more instability and stretching of the shoulder joint, leading to long periods off sports and poor performance. We therefore recommend early surgical fixation. Keyhole repair offers the advantages of less pain, less complications and an earlier return to sports.

• Acromioclavicular Joint Injuries

The hard, small lump you feel on the top of your shoulder is your Acromioclavicular Joint (AC-JOINT). This joint is very important for overhead and throwing athletes. It is commonly sprained by repeated falls on the shoulder and tackling. It can also dislocate resulting in a more prominent painful lump on your shoulder.

Sprained joints tend to cause more long-term pain than true dislocated joints. Injections and physiotherapy often improve the pain, but surgical removal of the joint is often required for persisting pain. This operation can be done by keyhole (arthroscopic) surgery, which has the advantages of less post-op pain and an early return to sport. Traditional open surgery can also weaken the shoulder, by dividing important ligaments. This is avoided with arthroscopic AC-JOINT excision.

• Rotator Cuff Tears

The rotator cuff is a very important group of tendons that provide movement and stability for your shoulder. Therefore, when it is damaged pain and weakness can be significant. Tears caused by injury, especially in athletes, benefit from early repair because the tears can get bigger and more difficult to repair later. Rotator cuff repair can be done by keyhole surgery or open surgery. We repair most tears by keyhole surgery with the same success rate as for open surgery.

• Biceps Injuries

The weak points of the biceps muscle are where the tendon attaches to the bone at the elbow and the junction between the biceps muscle and it's tendon. The biceps usually rupture at the elbow in athletes. You will usually feel a pop and notice a lump in the front of your arm. In athletes and manual workers prompt early repair is advisable, as it can be very difficult to repair these later. The biceps may also rupture at the shoulder - this is usually in older people and associate with rotator cuff tears - if surgery is needed the tendon is attached to the humerus (this is called a tenodesis).

• Labral Tears

The labrum is a cushion surrounding the socket of the shoulder joint (like the meniscus of the knee). Likewise, it can tear like the knee meniscus with injuries of the shoulder. Labral tears usually follow falls or direct blows to the shoulder but may also occur with throwing or pulling injuries. They can be diagnosed with MR Arthrograms (MR scan with special dye injected into the shoulder joint) and confirmed at keyhole surgery (arthroscopy). Large tears are associated with shoulder dislocations and called Bankart tears.

• Rugby Shoulder

The shoulder is commonly injured and a detailed article by Prof Len Funk explains the detail.

• Swimmers Shoulder

Swimming involves repetitive overhead activity, with muscular imbalances occurring around the shoulder complex to accommodate this. Thus, swimmers are prone to shoulder pain, with over two thirds of elite swimmers suffering this at some stage. Treatment usually involves addressing the muscular imbalance by an experienced shoulder therapist. Arthroscopic surgery may be required for subacromial impingement and shoulder instability.

• Shoulder Fractures

Fractures around the shoulder have always been difficult to treat operatively, thus the results of shoulder fractures have not been as good as other fractures. With new fixation devices and safer surgical techniques, we can fix difficult fractures early and allow early return to sports better than in the past.

• Frozen Shoulder

True frozen shoulder (a very stiff painful shoulder with no obvious cause) is very rare in athletes. However, a stiff painful shoulder following an injury (sometimes, quite minor) is not rare. In these cases, it is essential to treat the stiffness early and then also treat the underlying injury that caused the stiffness. The joint teamwork of an experienced physiotherapist and shoulder surgeon is very useful for an early recovery.

• Shoulder Arthritis

Arthritis is when a joint wear with age or overuse. The lubricant is reduced, and the joint becomes stiff and painful. Keeping the shoulder active and the muscles toned is of benefit, along with painkillers. However, when the pain is severe enough to affect daily life and sleep a joint replacement is of benefit.

2. Shoulder injuries in the throwing athlete

Overhand throwing places extremely high stresses on the shoulder, specifically to the anatomy that keeps the shoulder stable. In throwing athletes, these high stresses are repeated many times and can lead to a wide range of overuse injuries.

Although throwing injuries in the shoulder most commonly occur in baseball pitchers, they can be seen in any athlete who participates in sports that require repetitive overhand motions, such as volleyball, tennis, and some track and field events.

In addition to the ligaments and rotator cuff, muscles in the upper back play an important role in keeping the shoulder stable. These muscles include the trapezius, levator scapulae, rhomboids, and serratus anterior, and they are referred to as the scapular stabilizers. They control the scapula and clavicle bones — called the shoulder girdle — which functions as the foundation for the shoulder joint.

The phases of pitching a baseball

When one structure — such as the ligament system of the shoulder — becomes weakened due to repetitive stresses, other structures must handle the overload. As a result, a wide range of shoulder injuries can occur in the throwing athlete.

Common throwing injuries in the shoulder:

• SLAP Tears (Superior Labrum Anterior to Posterior)

In a SLAP injury, the top (superior) part of the labrum is injured. This top area is also where the long head of the biceps tendon attaches to the labrum. A SLAP tear occurs both in front (anterior) and in back (posterior) of this attachment point. Typical symptoms are a catching or locking sensation, and pain with certain shoulder movements. Pain deep within the shoulder or with certain arm positions is also common.

(Left) The labrum helps to deepen the shoulder socket.

(Right) This cross-section view of the shoulder socket shows a typical SLAP tear.

• Biceps Tendinitis and Tendon Tears

Repetitive throwing can inflame and irritate the upper biceps tendon. This is called biceps tendinitis. Pain in the front of the shoulder and weakness are common symptoms of biceps tendinitis. Occasionally, the damage to the tendon caused by tendinitis can result in a tear. A torn biceps tendon may cause a sudden, sharp pain in the upper arm. Some people will hear a popping or snapping noise when the tendon tears.

(Left) The biceps tendon helps to keep the head of the humerus centered in the glenoid socket.

(Right) Tendinitis causes the tendon to become red and swollen.

• Rotator Cuff Tendinitis

When a muscle or tendon is overworked, it can become inflamed. The rotator cuff is frequently irritated in throwers, resulting in tendinitis. Early symptoms include pain that radiates from the front of the shoulder to the side of the arm. Pain may be present during throwing, other activities, and at rest. As the problem progresses, pain may occur at night, and the athlete may experience a loss of strength and motion. Rotator cuff tears often begin by fraying. As the damage worsens, the tendon can tear.

Problems with the rotator cuff often lead to shoulder bursitis. There is a lubricating sac called a bursa between the rotator cuff and the bone on top of your shoulder (acromion). The bursa allows the rotator cuff tendons to glide freely when you move your arm. When the rotator cuff tendons are injured or damaged, this bursa can also become inflamed and painful.

• Internal Impingement

During the cocking phase of an overhand throw, the rotator cuff tendons at the back of the shoulder can get pinched between the humeral head and the glenoid. This is called internal impingement and may result in a partial tearing of the rotator cuff tendon. Internal impingement may also damage the labrum, causing part of it to peel off from the glenoid. Internal impingement may be due to some looseness in the structures at the front of the joint, as well as tightness in the back of the shoulder.

Pain and loss of throwing velocity will be the initial symptoms, rather than a sensation of the shoulder "slipping out of place." Occasionally, the thrower may feel the arm "go dead." A common term for instability many years ago was "dead arm syndrome."

• Glenohumeral Internal Rotation Deficit (GIRD)

As mentioned above, the extreme external rotation required to throw at high speeds typically causes the ligaments at the front of the shoulder to stretch and loosen. A natural and common result is that the soft tissues in the back of the shoulder tighten, leading to loss of internal rotation. This loss of internal rotation puts throwers at greater risk for labral and rotator cuff tears.

• Scapular Rotation Dysfunction (SICK Scapula)

Proper movement and rotation of the scapula over the chest wall is important during the throwing motion. The scapula (shoulder blade) connects to only one other bone: the clavicle. As a result, the scapula relies on several muscles in the upper back to keep it in position to support healthy shoulder movement. During throwing, repetitive use of scapular muscles creates changes in the muscles that affect the position of the scapula and increase the risk of shoulder injury. Scapular rotation dysfunction is characterized by drooping of the affected shoulder. The most common symptom is pain at the front of the shoulder, near the collarbone. In many throwing athletes with SICK scapula, the chest muscles tighten in response to changes in the upper back muscles. Lifting weights and chest strengthening exercises can aggravate this condition.

Prevention of shoulder injuries

Shoulder injuries can often be prevented, by following simple guidelines. Pre-season screening of athletes by an experienced physiotherapist can help prevent common sports injuries. This should include assessment and management of the following key areas:

1. Sports-specific technique: poor performance and shoulder pain commonly originate in bad habits of technique. Often, they are only clearly seen when muscle fatigue sets in. The variety of overhead movements required for each sport gives rise to very subtle and unique technique faults. These will depend on the type of sport and shoulder dominance.


2. Flexibility: flexibility varies for the different muscles around the shoulder. For the major power muscles, it is important that flexibility allows freedom of movement for the pelvis, trunk, scapula, and humerus. For the rotator cuff, the critical issue is the balance of forces centering the head of the humerus, and to a lesser degree, freedom of movement. It is more critical that the internal and external rotators are equally flexible, rather than how flexible they are.


3. Core stability: core stability is critical it is for the inner core of the body and providing a stable strong support for the shoulder to work off. A good shoulder needs a good foundation. The core also provides the kinetic chain for overhead activities, allowing the trunk muscles to transfer energy and momentum to the shoulder for overhead sports. For the shoulder, the critical areas are the lumbar and cervical spine and the scapulothoracic joint. If these areas are not stable, significant extra loading and strain is passed on to the shoulder joint.



4. Rotator-cuff strength and control: the rotator-cuff muscles are dependent on the good positioning of the scapula for effective control. If the scapula is angled too far forward or downward, for instance, while the tennis player reaches overhead to smash, the rotator-cuff muscles are biomechanically disadvantaged and may result in failure of the prime mover muscles to generate power. The rotator cuff should be balanced throughout the overhead movement, centering the humeral head on the glenoid. This requires equal strength and flexibility of the force couples of the rotator cuff.


5. General muscle strength: once the essential issues of technique, flexibility, core stability, and rotator-cuff control are being implemented, we then should also look at the 'outer core'. What is the rest of your body like - does it help or hinder the performance of the shoulder? Athletes often overwork and build up their 'mirror muscles' at the front of the shoulder, such as pec major, front deltoids, trapezius and rectus abdominis ("six pack"). What is often critically overlooked, however, is the imbalance that can develop between the front of the shoulder and the back. In those athletes that are carrying an overuse injury in the shoulder, nine times out of ten they have overdeveloped pecs and lats relative to their lower trapezius, rhomboids, posterior deltoids, and posterior rotator cuff.