ANATOMY OF THE SHOULDER
The shoulder joint consists of 3 bones: the scapula, the clavicle and the humerus. The majority of shoulder movement occurs in the Glenohumeral joint (ball and socket) of the humerus (arm bone) with the scapula or shoulder blade and the coracoacromial arch above . The shoulder joint allows the arm to be lifted forwards and backwards (flexion, extension), away from and against the side of the body (abduction, adduction) and rotated inwards and outwards (internal, external rotation). When the arm is abducted away from the side of the body, it can only raise so far before the arm bone impacts on the bony coracoacromial arch. Therefore, in order to raise your arm more than 90 degrees, the arm must externally rotate.
The Glenohumaeral joint has a very large range of motion. This joint does not rely on ligaments to limit and control excess movement, it engages the use of 4 small muscles known as the Rotator Cuff. If one or more of these muscles is injured, weak, or swollen, the joint will be misaligned, ranges of movement will be decreased, and pain will follow.
There are also several large muscles which add strength to the shoulder, including deltoid, biceps, triceps, pectorals, latissimus dorsi and rhomboids. If one of these muscles is injured, weak or overly strong it will cause dysfunction of the shoulder and may also cause pain in the neck or back. Normal shoulder movement and strength depends on a balance of these large muscles and the Rotator Cuff musculature. Any imbalance of these muscles can lead to a number of Shoulder conditions.
Rotator Cuff Tendonitis
The Rotator Cuff musculature attaches to the top of the Humerus, or arm bone. The supraspinatus, infraspinatus and teres minor attach to the back of the scapula. The subscapularis attaches to the front of the scapula. Overuse of any of these muscles may cause inflammation or a tendonitis. Weakness or strain of one or more of these muscles causes an imbalance in the movement of the shoulder joint and may lead to impingement of the tendons or bursa against the coracoacromial arch, causing inflammation. Rotator cuff injuries usually occur due to a sports injury, such as overthrowing a baseball/football, lifting heavy weights improperly. Chronic repetitve movements are also known to cause this type of shoulder dysfunction.
of a rotator cuff injury include: pain, deep aching over the shoulder and top of the arm, restricted ranges of motion, decreased strength, etc.. Pain is normally worse at night and can be very sharp with certain movements such as putting on a coat, or reaching behind. If the arm is abducted away from the side, there is a
between 60º and 120º. If the arm is fully externally rotated the abduction may be full range and painless.
TREATMENT of a rotator cuff injury by a Chiropractor includes Low Volt Current or TENS, Ultrasound, Joint Mobilization, and Adjustments. TENS and Ultrasound help to eliminate inflammation within the musculature allowing it to heal with little of no permanent scar tissue. Joint manipulation allows correction of joint mechanics, enabling the Glenohumeral joint to produce synovial fluid and repair itself. Treatment should begin as soon as possible, a rotator cuff injury leads to bursitis and a condition known as frozen shoulder if left untreated.
A bursa is a fluid filled sac that protects tendons from injury where they rest over bone. There are many bursae in the shoulder, the most commonly affected is the Subacromial bursa . This bursa protects and enables smooth movement of the supraspinatus tendon and head of humerus under the coracoacromial arch. Chronic injury, to the supraspinatus tendon, rotator cuff imbalance or even carrying heavy objects resting on the shoulder joint may cause the bursa to become inflamed. Sports injuries and direct trauma to the area can also lead to bursitis.
Effective treatment of shoulder bursitis begins with decreasing inflammation. TENS, Ultrasound are modalities used to decrease the inflammatory process. Patients with bursitis are encouraged to avoid repetitive shoulder movements, sleep on the unaffected shoulder, and apply ice compresses to the area. Bursitis responds to treatment within the first 4-6 visits. Cold therapy works as a natural anti-inflammatory, and should be continued until normal ranges of movement are pain free. Patients undergoing treatment should avoid any heavy lifting, abduction of the arm, excessive rotation, etc. If treatment is started early most patients can avoid Cortisone injections.
Frozen shoulder is also known as Adhesive Capsulities. A frozen shoulder condition is an inflamed shoulder joint that becomes
difficult to move as the synovial fluid thickens. This inflammation begins within the joint surface making the joint very painful. The pain starts gradually causing the shoulder to stiffen, eventually all movements are very restricted, especially abduction and internal rotation. The pain starts in the shoulder joint an can radiate down the arm.
Adhesive Capsulitis can last anywhere from 6 months to 2 years. Starting treatment in the early stages is recommended in order to decrease length of symptoms.
Typically, a Frozen Shoulder condition follows Bursitis, Tendonitis, sports injury or a repetitive strain. Any injury to the shoulder should be treated immediately.
Treatment by a Chiropractor involves decreasing the inflammation that is present, reducing muscular hypertonicity, restoring normal shoulder movement including the Cervial/Thoracic spine, Glenohumeral joint, AC joint, SC joint. Massage Therapy helps in reducing muscular spasm of the Rhomboids,Traps, Scalenes, Deltoids, Levator Scapula, Teres and Pectoral muscualture. Patients are encouraged to start treatment early to avoid the long term effects of the inflammation which can lead to Capsulitis. Treatment includes modalities to eliminate inflammation and restore joint mobility. Patients should avoid physical activity, apply cold compresses to the shoulder region, sleep on opposite shoulder, to help improve recovery time.
This condition is caused by straining the biceps tendon located on the front of the shoulder. Injury to the tendon can occur during weight lifting, overthrowing, shovelling, even lifting heavy grocery bags. Pain is localized to the front of the shoulder, in severe case the pain can radiate down the arm. Patients with BT are unable to flex arm ( bring wrist to shoulder ), lift and experience point tenderness where the bicep tendon connects to the shoulder. BT can occur with a Rotator Cuff injury, Bursitis, direct trauma to the front of the arm and overuse.
Treatment for BT is similar to most shoulder injuries with the main objective being to limit and reduce inflammation of the tendon as quickly as possible to avoid permanent damage. Modalities are use to reduce inflammation and restore normal mechanics and blood flow to the area. Massage is incorporated to aid in reducing scar tissue formation. Patients are encouraged to rest, avoid physical activity, sleep on opposite shoulder, apply ice to the area, and gradually start ranges of motion exercises. This condition responds well when treatment is started early.
Shoulder dislocation can occur with an acute sports injury common in contact sports like hockey and football. The shoulder normally dislocates through the front of the joint. Once the dislocation has been reset, it is important to strengthen the joint as the Rotator Cuff musculature will have been stressed and this can lead to chronic instability. Effective treatment of this condition includes small, very light exercises to strengthen the RC muscles. Patients should avoid physical activity during the strengthening phase of treatment.
ACROMIOCLAVICULAR JOINT DISLOCATION
The AC joint can become dislocated with forceful injury to the front of the shoulder. This injury is common in football, hockey, martial arts, wrestling, soccer etc. This condition responds well to early treatment. Correcting the alignment of the AC joint can reduce the chances of arthritis of this joint in later years. Patients may be left with a prominent bump above the AC joint.
Usually of the acromioclavicular joint due to recurrent injuries, subluxations and chronic rotator cuff tendonitis. Causes pain on reaching high overhead, which is therefore best avoided! Best managed by improving rotator cuff stability.Of the glenohumeral joint itself, is more rare and is usually secondary to fractures or chronic stiffness due to rotator cuff tendonitis or frozen shoulder.