Shoulder pain can be caused by a number of different conditions, including:
- Clavicle fracture also referred to as a broken collarbone
- Acromioclavicular joint disorders (AC)
- Frozen shoulder
- Rotator cuff disorders
- Shoulder dislocation / instability
Clavicle fracture also referred to as a broken collarbone
A broken collarbone usually happens after a fall onto the shoulder. It takes about six to eight weeks to heal in adults and three to four weeks in children.
The collarbone, or clavicle, is a long slender bone that runs from the breastbone to each of the shoulders. You should be able to feel it running across the top of your chest, just below your neck. The collarbone is connected to the breastbone and to the shoulder blade via tough bands of tissue called ligaments.
AC - Acromioclavicular Joint Injuries
The acromioclavicular joint, or AC joint, is a joint at the top of the shoulder. It is the junction between the acromion (part of the scapula that forms the highest point of the shoulder) and the clavicle.
The AC joint allows the ability to raise the arm above the head. This joint functions as a pivot point (although technically it is a gliding synovial joint), acting like a strut to help with movement of the scapula resulting in a greater degree of arm rotation.
Frozen shoulder is a painful condition that affects movement of the shoulder.
Frozen shoulder is also known as adhesive capsulitis or shoulder contracture.
If you have frozen shoulder, the amount of movement in your shoulder joint will be reduced. In severe cases, you may not be able to move your shoulder at all.
Rotator Cuff Disorders
The rotator cuff is a group of four muscles that are positioned around the shoulder joint and work as one unit. They help to stabilise the shoulder joint and also help with shoulder joint movement. The four tendons of the rotator cuff muscles join together to form one larger tendon, called the rotator cuff tendon. This tendon attaches to the head of the humerus (the bony surface at the top of the upper arm bone). There is a space underneath the acromion of the scapula, called the subacromial space. The rotator cuff tendon passes through here.
The shoulder joint has the greatest range of motion of any joint in the body and as a result is particularly susceptible to Shoulder dislocation or luxation.
The shoulder joint can dislocate forward Anterior dislocation, backward Posterior dislocation or downward Inferior dislocation. Subluxation is a partial dislocation that occurs when bones in a joint become displaced or misaligned. It is often caused by a sudden impact to the joint.
A common type of shoulder dislocation is when the shoulder slips forward (anterior instability). This means the upper arm bone moved forward and down out of its joint. It may happen when the arm is put in a throwing position.
Hemiplegic Shoulder Pain – from hemorrhagic or ischemic stroke.
Shoulder pain resulting from hemiplegia (Hemiplegia is total paralysis of the arm, leg, and trunk on the same side of the body) is a common clinical consequence of a focal cerebral insult resulting from a vascular lesion (i.e. hemorrhagic or ischemic stroke).
Painful hemiplegic shoulder can occur as early as 2 weeks post stroke but an onset time of 2-3 months post stroke is more typical. Shoulder pain can negatively affect rehabilitation outcomes as good shoulder function is a prerequisite for successful transfers, maintaining balance, performing activities of daily living and for effective hand function. Similarly, shoulder hand syndrome is pervasive in hemiplegic patients and can lead to significant medical complications.
The shoulder is susceptible to arthritis in different areas both in the glenohumeral joint (ball and socket joint of the shoulder) and in the acromioclavicular joint at the top of the shoulder.