The shoulder joint is the most mobile joint and this makes it intrinsically unstable, thereby making it the most often dislocated joint in the body.
The head of the humerus (upper arm) fits in to the glenoid fossa of the scapula (shoulder blade). The glenoid fossa is shallow, thus, the other structures surrounding the joint need to maintain joint stability.
When the structures within the joint and / or surrounding the joint get weakened, dislocation occurs. In the joint, a fibrous ring of cartilage extends from the glenoid fossa and proffers a deeper repository for the head of the humerus. The capsule tissue maintains stability. The rotator cuff muscles and the tendons which move the joint give considerable protection as well.
What Causes A Dislocated Shoulder?
Dislocation occurs when the head of the humerus gets powerfully removed from the socket. Maximum shoulder dislocations are anterior, i.e. the head of the humerus is moved to a location in front of the joint. Anterior dislocation occurs when the shoulder is in a defenseless position; e.g. when the arm is held over the head with the elbow bent, and a force is applied pushing the elbow backwards and moves the head of the humerus out of the glenoid fossa or falling on an outstretched hand.
Posterior shoulder dislocations occur when the head of the humerus has moved backwards. Posterior dislocations are rare and are related to seizures, lightning strikes, and electrical injuries.
Dislocations in younger people occur due to trauma and are associated with sports or falls. Older people develop a dislocation because of a gradual weakening of the ligaments and cartilage that support the shoulder joint in conjunct with trauma.
Symptoms Of A Dislocated Shoulder
A dislocated shoulder is characterized by:
- Severe pain and the patient will refuse to move the arm in any direction.
- The muscles go in to spasm, making any movement agonizing.
- The patient will hold the arm slightly away from the body.
- A bulge may be apparent in front of the shoulder joint.
- Sweating, nausea, vomiting, giddiness and fatigue are associated symptoms.
How To Fix A Dislocated Shoulder?
The chief aim is to reduce the dislocation and return the head of the humerus to its original place in the glenoid fossa. The decision as to which technique is employed to reduce the dislocation depends on the situation, patient, and experience of the doctor. By and large, doctors make use of a closed reduction, i.e. no incision is made in to the joint to return the bones to their normal position. Open reduction is surgical intervention to manage the dislocation.
Closed reduction
- Scapular manipulation: The patient will lie down and the physician will rotate the scapula, dislodging the head of the humerus, and facilitating relocation. An assistant is required to help stabilize the arm.
- External rotation: The patient lies down and the doctor will flex the elbow to 90 degrees and slowly and progressively rotate the shoulder outwards, helping the shoulder to relocate.
- Traction counter traction: With the patient lying down, a sheet is coiled around the armpit. The doctor pulls down on the arm, whilst the assistant pulls on the sheet to provide counter traction. As the muscles relax, the head of the humerus returns to normal position.
All these procedures are closed reduction. In exceptional circumstances, it may be difficult to reduce the shoulder joint because a ligament, tendon or bone fragment may get caught in the joint, not allowing relocation. Thus, an open reduction by an orthopedic surgeon becomes necessary.
Open reduction: Pain medications as well as muscle relaxants are given to the patient before and during the procedure. Local or general anesthesia is administered and the shoulder reduction is carried out.