Ligaments hold one bone to another bone and limit the amount of motion available in the joint. This prevents excess movement or motion in directions not intended for a particular joint. The tighter the ligaments are, the less motion available. Because the shoulder is a highly mobile joint, the ligaments must be loose to allow motion in all directions. This creates some inherent instability in the joint, and an avenue to potential injury.
Anterior Ligament Sprain/Dislocation
This injury usually occurs when we raise the arm overhead or out to the side and apply a force, such as with retrieving a heavy object from an overhead shelf. If the load is too great, then the ligaments in the front of the shoulder become overloaded and can tear, causing a sprain. If the ligaments tear enough, then the bones can separate and cause a dislocated shoulder. Dislocations should get immediate medical attention in the emergency room. Treatment involves applying traction to the joint, which allows the shoulder to return to its normal position and then a period of immobilization to allow the ligaments to heal.
Unfortunately, the ligaments do not heal quite as tightly as they once were. The shoulder becomes increasingly unstable, disposing it to another dislocation. Conservative treatment following a dislocation involves strengthening of the rotator cuff, a group of four muscles that provide additional stability to the shoulder. As you move your arm through space, the rotator cuff sucks the head of the arm bone, medically termed the humerus, into the socket. After a dislocation, it is even more important to keep the rotator cuff working properly. You may be referred to a physical therapist, who can provide instruction in the proper exercises.
Should the shoulder continue to dislocate, surgical intervention may be required. This entails tightening the shoulder capsule by “pulling up the slack” in the loose ligaments and stitching them back in place. This surgery is highly successful at stopping future dislocations, but there is a period of immobilization and rehabilitation for several weeks following the surgery.
This is a common traumatic injury caused by falling on an outstretched hand. With this injury, the force of landing on the hand is transmitted through the shoulder, causing a tear in the ligament that holds the collarbone in place. The result is a dislocation of the joint where the collarbone meets the shoulder blade, located at the bony area on top of the shoulder. This joint is called your acromioclavicular, or AC joint, and because this is the pivot point where the shoulder blade rotates, an injury here can cause significant loss of function in the arm, especially in the overhead range of motion. Minor sprains in the ligament may heal, but active individuals who have difficulty or pain with arm use may need to undergo surgical correction, as conservative treatment usually will not restore proper mechanics and movement patterns. Surgery involves harvesting a tendon from elsewhere in the body and using is as a replacement for the broken ligament. This effectively anchors the collarbone back in its correct position.
Medically termed adhesive capsulitis, this condition may be a result of injury to the shoulder, but just as often occurs without any type of trauma. It is an inflammation of the shoulder joint capsule, which contains the shoulder ligaments. As the capsule becomes inflamed and thickened, the shoulder becomes painful and loses significant mobility. Frozen shoulder may persist from several months to a year or longer and usually follows a predictable pattern of presentation that includes three stages.
1. The acute stage is marked by sharp pain in the shoulder throughout the range of motion, but especially with reaching overhead and out to the side. Shoulder mobility becomes limited.
2. During the frozen stage, acute pain starts to subside, but mobility of the shoulder continues to be limited.
3. The final phase is the thawing phase, where the joint mobility of the shoulder begins to improve, and functional use returns.
Although frozen shoulder can afflict a wide range of people, there are certain risk factors that may dispose someone to getting this condition including diabetes, cardiac disease, and hypo or hyperthyroid issues. Treatment is usually non surgical, as the condition usually gets better with time. During the acute and frozen phases, anti-inflammatory medications may be prescribed, as well as a steroid injection directly into the joint capsule, which significantly limits the degree of inflammation. Physical therapy may be ordered in order to learn some gentle mobility exercises, followed by more aggressive stretching and mobilization of the shoulder as the condition progresses into the thawing phase.