Shoulder Pain

Shoulder is a 'ball and socket' joint. Shoulder is the most mobile and flexible joint in the human body as the ball is quite large as compared to the shallow socket. The joint is reasonably stable due to complex, delicately balanced arrangement of bones, muscles, tendons and ligaments. Three bones are interconnected at shoulder to form a girdle – collar bone (clavicle), shoulder blade (scapula) and humerus (bone in the arm – shoulder to elbow). Acromion is a part of shoulder blade bone which projects above head of humerus and restricts upward arm movement at shoulder joint. Ligaments of shoulder joint are not very tight and capsule too is quite lax to allow free movement. Four small muscles (the rotator cuff) retain the head of humerus in the socket and act as dynamic ligaments. Long muscles such as deltoid (overlying shoulder), biceps (front of arm), triceps (back of arm) and others move shoulder in various directions. Subacromial bursa, a fluid filled sac, underlies acromion and extending downwards acts as a cushion preventing rubbing of rotator cuff tendons over the bones.
Greater range of movements at shoulder makes it more prone to injury and resultant pain. Pain interferes with day-to-day functions. Pain also disturbs sleep as lying on the side of affected shoulder is painful. Risk of shoulder problem is particularly high in athletes, older people and in those who work with overhead movements (swimming, throwing, painting and construction work).

Common problems around shoulder joint leading to pain are as follows:

  • Frozen shoulder (Adhesive capsulitis): Mild to severe restriction of shoulder movement along with pain is a common complaint. Risk of frozen shoulder increases as age advances beyond 40 years. It is more common in females and in those with diabetes, previous shoulder injury or surgery, heart or lung disease, stroke and overactive thyroid gland. Deficiencies of calcium as well as that of vitamins B12 and D are also implicated in various conditions leading to shoulder weakness and pain. Inflammation of soft tissue around shoulder joint leads to thickening and tightening due to adhesions and restricts joint movement. Frozen shoulder usually starts as pain for 3-9 months. This is followed by phase of restricted motion lasting for 4-12 months. Discomfort and stiffness makes it difficult to carry out routine activities such as making hair, buttoning blouse or reaching a high shelf. Pain in these activities is noted at the extreme of a particular motion. Lying on the affected side is also difficult due to painful shoulder. Pain will reduce slowly over a period of 6-24 month though restriction persists and shoulder never regains its complete normal range of movement. Exercise under expert physiotherapy guidance is the best treatment for frozen shoulder. Painkillers can be used in initial stages. Oral steroids may also be useful in early stages of frozen shoulder. Local steroid injection may reduce pain in some cases. Manipulation under general anesthesia and other surgical procedures should be considered in recalcitrant cases.
  • Rotator Cuff Lesions (Swimmer’s shoulder): Four muscles of rotator cuff steady the shoulder during movements of arm. Muscles of rotator cuff or their tendons can get swollen due to repetitive overuse or get torn during a single stressful event. Supraspinatus muscle and tendon, which form upper part of the cuff, are most often injured as they lie between bones. Pain and limitation of movements is a common feature. Pain is usually worse during overhead activities. Lifting the arm away from body becomes painful. Avoidance of stressful shoulder movements (but not complete rest), painkillers and exercises under supervision of a physiotherapist is the treatment of choice. Local steroid injection or surgery may be required in selected cases.
  • Calcific Tendonitis:Deposition of calcium (chalk like)in rotator cuff tendons without any symptoms is seen in 3-20% population. It is more common in elderly individuals although the process in not exactly age related degeneration. The exact cause of calcium deposition is not known. Pain in calcific tendonitis can be of sudden onset and very severe. The pain may awaken a patient from sleep. The pain usually radiates lower down the arm and may radiate upwards towards neck. Pain is often aggravated by raising arm above the shoulder. Stiffness and weakness of shoulder may be associated. Acute severe symptoms can resolve spontaneously in 3-4 weeks. In other non-acute cases pain is mild with intermittent flares. Shoulder may get locked due to large calcium deposit. X-ray of shoulder may show calcification. 70% patients respond to pain killers and exercises under supervision of an expert physiotherapist. Local steroid injections, needling and lavage and surgery may be contemplated in nonresponsive cases. Calcium depositions can recur in 16-18% cases following surgery.
  • Subarachnoid Bursitis: Supraspinatus muscle originates from the top of the shoulder blade and runs under the acromion to get attached to the top of the humerus bone. A bursa, largest in our body, intervenes between this muscle and acromion and protects friction of the muscle against bone. Inflammation of this Subacromial bursa usually results from overuse and may indicate degenerative joint disease. Painful movements and tenderness on pressure above head of femur bone are important features. A swelling may present in the area. Treatment consists of painkillers, rest (avoidance of strenuous activities), exercises and local steroid injections.
  • Bicipital Tendinitis: One of the tendinous origins of biceps muscle lies just in front of the shoulder joint. Bicipital tendinitis can occur as a part of rotator cuff lesions or may occur after an unusual stress. Overuse and wear and tear are common causes of Bicipital tendinitis.Pain increases on local pressure below the front of shoulder joint. Conservative treatment with painkillers, rest and heat is usually sufficient. Local steroid injection also helps but must be given carefully as this can lead to rupture of the tendon. Surgery is rarely indicated.


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