Shoulder Surgery
Shoulders, elbows, innovation
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Impingement

 

The modern concepts of subacromial impingement start with Charles Neer (Obituary).  He hypothesized that impingement of the rotator cuff is from the anterior  acromion, the coracoacromial ligament, and the acromioclavicular joint rather than by just the lateral aspect of the acromion. There is also evidence that formation of spurs in the lateral acromion leads to attrition damage to the cuff.

The modern concepts of subacromial impingement start with Charles Neer (Obituary).  He hypothesized that impingement of the rotator cuff is from the anterior  acromion, the coracoacromial ligament, and the acromioclavicular joint rather than by just the lateral aspect of the acromion. There is also evidence that formation of spurs in the lateral acromion leads to attrition damage to the cuff.

Diagnosis and Clinical Tests

Calcific tendonitis

deposits of calcium (a crystalline calcium phosphate) in any tendon of the body, but most commonly this is seen in the tendons of the rotator cuff, especially the supraspinatus. This can cause intense pain in the shoulder due to a pressure build up as well as chemical irritation.

Diagnosis Clinical features can be similar to impingement or frozen shoulder, and definitive diagnosis is made by X rays and/or scans Treatment Ultrasound guided needle (barbotage) - a needle is introduced into the calcium repeatedly to break up the mass. The area is throughly washed with saline.

Surgery - Performed through arthroscopic techniques, this is usually very successful in releasing the calcium and relieving pain

Physical examination is often conclusive but Neer's test1 is an useful adjunct. This involves injecting about 10 mls of local anaesthetic in the subacromial bursa and then repeating the examination. This abolishes the pain in impingement. This is also a reliable test for predicting results after subacromial decompression2.

Xrays may demonstrate a curved/hooked acromion, and ultrasound scanning may provide evidence of dynamic impingement.

Treatment

Non operative treatment with analgesics and physiotherapy is often successful, but some patients will need surgery in the form of a subacromial decompression.

Steroid injections in the subacromial space can be effective in the short term, but there is little evidence to show any long term benefit. Rotator cuff tears should be excluded before steroids are injected. This often requires scans.

For a more detailed discussion on steroid injections look here

Subacromial decompression

Normally undertaken through keyhole techniques, this involves a day case procedure (Usually home the day of surgery) performed under general anaesthetic and often a nerve block as well. Two or three small incisions are made and part of the acromion with any bony spurs are shaved away. The coraco-acromial ligament is also released. This creates more space for the shoulder to move and the rotator cuff tendons to glide freely.

The recovery is fairly quick and most patients are driving witin 10 days. Return to work depends on the type of work, but there are no specific restrictions placed on patients.

Physiotherapy is essential after this operation. This is to enable return of movements and strength while maintaining a normal movement pattern

Usually there is minimal or no scarring, and over 85% of patients report significant improvent in pain and function.

References

  1. Neer, C. S., II: Impingement lesions. Clin. Orthop., 173: 70-77, 1983.

  2. Mair SD, Viola RW, Gill TJ, Briggs KK, Hawkins RJ. Can the impingement test predict outcome after arthroscopic subacromial decompression? J Shoulder Elbow Surg. 2004 Mar-Apr;13(2):150-3.