Dislocations

Dislocation of a joint occurs when there is a separation of two bones at a joint. It can be very difficult sometimes to clinically distinguish between a fracture and dislocation and the two can occur together. If there is clinical doubt the limb should be immobilised, splinted and radiographs taken, before attempting any manipulation. Dislocations are normally associated with a soft tissue injury, which may need to be immobilised pre and post-reduction, to reduce pain and prevent further damage.

Shoulder Dislocations

The shoulder comprises 20% of all rugby injuries being the second most commonly injured joint after the knee.  35% of shoulder injuries are recurrent injuries.  In rugby the part of the game most strongly associated with shoulder injuries is the tackle, accounting for 49% of all injuries (Brooks et al 2005). Acute shoulder dislocation is a relatively common injury in rugby, 95-98% of which are anterior dislocations.

Mechanism: Anterior dislocation of the shoulder is described most commonly as due to a fall with a posteriorly directed force onto an outstretched arm, which is abducted and externally rotated. A study which specifically analysed shoulder trauma in rugby players, described a position of forced abduction and external rotation (ABER), accounting for 32% of recurrent injuries. This was either in a tackle situation or when landing with the upper limb outstretched holding the ball when trying to score a try (Funk and Snow 2007). Posterior dislocation is much less common and usually caused by an anterior force when the shoulder is held in internal rotation and adduction.

Presentation: Most often this will follow a contact episode and the player will complain of shoulder pain and dysfunction.

Anterior Dislocation: The player will generally cradle the arm to their side. Typically there is loss of the deltoid roundness, although in modern day players, the wearing of shoulder pads makes this almost impossible to see. It may be detected by palpation, although once again, this may be difficult due to the tight shirts and shoulder pads. Sometimes it is possible to palpate the humeral head as a fullness in the clavipectoral groove.

Attempting active shoulder movements, will be painful and severely limited. The player often knows their shoulder has dislocated. Check for, and document, the presence of a radial pulse. If possible, check the sensation over the “Regimental badge” area adjacent to the insertion of deltoid; this may be impractical due to clothing and padding. This is to assess and document if the axillary nerve is affected The integrity of the radial nerve can be assessed by assessing wrist and elbow function, and testing for reduced sensation over the dorsum of the hand.

Posterior Dislocation: The player may present with the arm adducted and internally rotated, or holding their arm in forward elevation with their opposite hand and complaining of increased pain if they try to lower it and attempting abduction or lateral rotation are painful. A posterior bulge may be present palpated below the acromion; once again this may be difficult to identify due to clothing and padding. The same neurovascular checks need to be carried out as for an anterior dislocation.

Removal of player from field of play: If a dislocation is suspected the player will need to leave the field of play. Generally the player will be able to walk off the field, the limb may be supported by the player, the player’s shirt can be rolled up from below, over the arm to provide support, or a Polysling can be applied with a swathe around the chest.

Reduction Techniques: As soon as possible, give pain relief. Early reduction is recommended when dislocation has occurred, to reduce the amount of muscle spasm that must be overcome and minimise the amount of stretch and compression of neurovascular structures (Christofi T, et al 2007).

If the person attempting reduction is not confident when applying these techniques they will fail to reduce the joint, will induce further muscle spasm and make the player more anxious. So be firm and controlled when carrying out any of the techniques. DO NOT FORCE THE RELOCATION, there may be other damage!

Spaso Technique: The player is placed in the supine position. The carer stands on the same side as the dislocation and takes hold of the affected arm by the wrist with a two-handed grip and gently raises the limb to approximately 90° flexion whilst applying gentle traction. The shoulder is then externally rotated, reduction usually occurs spontaneously.

Kocher's Method: With the player seated on a chair with back support, bend the affected arm at 90º at the elbow, ask the player to hold the elbow adducted against their body. The carer grasps their wrist and slowly externally rotates the arm between 70º to 85º until resistance is felt. Lift the externally rotated upper arm as far as possible forwards. From this point internally rotate the shoulder bringing the patient's hand towards the opposite shoulder. The humeral head should now slip back into the glenoid fossa.

Modified Milch: Have the player seated on a chair with back support, stand behind the affected shoulder and place your near hand over the superior aspect of the shoulder girdle to fix the scapula. Holding the arm at the wrist, slowly and gently abduct the arm to 100°, whilst gradually externally rotating the arm as it is lifted. If the relocation does not occur an assistant can gently push the humeral head anteriorly.

Stimson Method: Position the player prone on an examination table with the affected arm hanging over the side of the table. An assistant applies a downward traction force on the arm or attaches a 5-10 kg weight to the wrist, which should not touch the floor. Spontaneous reduction should occur as the shoulder muscles relax.

Following reduction, reassess and document the neurovascular status. Place the arm in a Polysling with the swathe around the chest and transport to hospital for radiographs, any further treatment and appropriate follow up.

Elbow Dislocation

The elbow joint is the second most commonly dislocated joint of the upper limb, and is more commonly injured in adolescents and young adults. It has been reported that elbow dislocation most frequently occurs in a posterolateral direction (90%) due to the stable bone configuration and muscular support across the joint.

The most common cause of posterior elbow dislocation is a fall onto an outstretched hand or a direct blow to the elbow.

Signs & symptoms

• Severe pain at the time of injury
• Loss of elbow function
• Visible deformity
• Tenderness over the dislocation
• Swelling and bruising around the elbow
• Numbness or paralysis in the arm below the dislocation
• Reduced or absent pulse at the wrist

Prior to attempting joint reduction, the neurovascular status needs to be checked and documented and adequate analgesia should be administered

Examine the functions of the radial (wrist extension), median (wrist pronation), and ulnar (flexion of 4th and 5th fingers) nerves before attempting reduction.

The median nerve or brachial artery can be injured at the time of reduction by becoming trapped in the joint. Altered neurovascular status is a medical emergency and necessitates rapid transport to hospital.

Reduction; lie the patient supine with the affected arm abducted in slight flexion, an assistant applies counter-traction to the humerus, whilst the operator stands to the same side facing the player and supports the flexed, and slightly supinated forearm, with their near arm and supports the player’s arm against their body. At the same time the operator “hooks” his fingers of both hands over the superior aspect of the prominence of the olecranon whilst applying in-line traction to the forearm.

An alternative method is to lay the player face down/prone on an examination couch with the shoulder in abduction, and the humerus supported by the couch, and the elbow flexed. The examiner takes hold of the forearm just above the wrist, and uses the other arm to stabilise the humerus around the elbow and with their thumb resting on the olecranon, applies gentle in-line traction to the forearm, while the thumb is used to apply gentle pressure to facilitate reduction.

Following reduction, the neurovascular status must be rechecked and documented,  player‘s arm is then placed in a sling and transported for check radiographs.

Possible complications:

• Injury to brachial artery
• Injury to a nerve
• Compartment syndrome
• Fractures of the head of the radius and/or coronoid process of the ulnar
• Fracture and entrapment of the medial epicondyle
• Heterotropic ossification (myositis ossificans)