The shoulder is the most mobile joint in the body. Because it offers movement in many directions the joint is at risk for dislocation. Traumatic shoulder dislocation is the most common major joint dislocation affecting 2% of the population during their lifetime. Dislocation is often accompanied by a labral lesion which predisposes to chronic shoulder instability. 70% of dislocations occur in young men. Older women are also at risk.
The shoulder is a ball and socket joint made of the head of the upper arm bone (the ball of the humerus), which fits into the socket of the scapula or shoulder blade. The socket is fairly flat and is surrounded by a rim of cartilage called the labrum, which helps to deepen the socket, and acts like a bumper. The primary joint stabilizer is the rotator cuff made of a group of muscles and ligaments. The ligaments provide support and stability and allow the joint to move within its normal range of motion. The muscles and tendons offer stability during motion.
What is a shoulder dislocation?
Dislocation occurs when the head of the upper arm bone is forced out of its socket by trauma from an auto accident, a fall on an outstretched arm, a direct hit to the shoulder or the sharp twist of the arm from contact sports like football, baseball, basketball and volley ball. It requires immediate intervention.
Anterior dislocation is the most common type of shoulder dislocation. However, 25% of anterior shoulder dislocations involve a fracture of the joint. Symptoms include severe pain, bruising and swelling, the inability to move the shoulder, muscle spasms, numbness, tingling and weakness and shoulder instability.
Acute treatment is called a reduction where the shoulder is restored to its normal anatomical position either by manipulation (closed reduction) or open surgery (open reduction) to treat the dislocation and any fracture and or labral tear. The ideal treatment of an acute dislocation is still controversial.
Young and active patients and athletes are most likely to benefit from surgery. Additionally, when a patient also has a labral tear or a fracture, early surgery to repair the tear and/or treat the fracture reduces the risk of recurrent dislocations.
A partial dislocation is called Subluxation (Instability). It is related to lose joints, which may be hereditary. It is often caused by repetitive overhead motion found in sports like baseball and volleyball.
What is a labral tear?
Dislocation often injures the supporting ligaments and can tear the cartilage rim called the labrum. This type of tear is called a Bankart tear. A labral tear can also occur from a fall on an outstretch arm, heavy lifting and a forceful overhead motion in sports that involve overhead throwing. This type of tear is called a SLAP tear. Symptoms of a labral tear include dull and aching pain and instability, catching and locking of the joint, night pain, reduced range of motion and loss of strength.
Minor tears can sometimes heal with nonsurgical treatment and physical therapy. However, competitive athletes and individuals who participate is repetitive overhead motions may be unable to return to sports or labor that requires overhead motion without surgery. Minimally invasive arthroscopic surgery is the most often procedure.
Rehabilitation and return to play
The goal is to prevent long-term joint instability. The risk of recurrent dislocation in young athletes with a first-time dislocation is high. When the athlete returns to activity without rehabilitation recurrent dislocation ranges from 37% to 90%.
The rehabilitation protocol will depend on the injury and the treatment. The goal is to restore range of motion, stability, flexibility and strength. Specially designed rehab protocols have been shown to accelerate time to return to play, but the patient must be pain free, and demonstrate shoulder strength and functional range of motion that allows sport specific participation. Optimal management requires each patient to be evaluated and rehab personalized.
Patients typically can return to sport from 4-6 months after surgery and most are able to achieve pre-injury levels of activity. However, the appropriate time to return to play is determined by a full functional assessment.
Center’s for Advanced Orthopaedics team of sports, rehabilitation and surgical professionals offer next level training, surgical expertise, and rehabilitative care as part of a holistic care program to get you back to the life and hobbies you love better than ever.