How common is shoulder pain?
Shoulder pain is a very common condition. About 4.7% to 46.7% population suffers from it in one year. The chance of suffering shoulder pain in a lifetime is up to 66.7% and at any point in time, every 4th or 5th person has shoulder pain.
How is our shoulder joint?
The shoulder joint is a ball and socket joint with a wide range of mobility; but it is not a single joint, it has 4 joints that work together. These four joints are glenohumeral joint, acromioclavicular joint, thoracoscapular joint and sternoclavicular joint. There are also several tendons, ligaments, bursas around the joint, and any of these alone or in combination can be a source of pain. The most important tendons are together called rotator cuff tendons. These are the tendons that lift & rotate the shoulder in different directions.
What are the causes of shoulder pain?
The common causes of shoulder pain are tendinopathies and tear, frozen shoulder or adhesive capsulitis, bursitis, damaged cartilages or ligaments, and arthritis of these joints. Fracture or tumor is a less common cause of shoulder pain. Sometimes shoulder pain is not because of shoulder pathology, it may be referred pain from the cervical spine, chest, or abdominal pathology.
The most common causes of shoulder pain are rotator cuff tendinopathies and frequently tendon tear is associated with these tendinopathies. These tears can be partial-thickness tears or full-thickness tears. If a tear is there in tendons, there will be pain and restricted movements of the shoulder. Among all these tendinopathies, supraspinatus tendinopathy is the most common. Surgery was the main treatment for a tear in earlier days, but regeneration therapy with platelet-rich plasma is the most popular non-operative treatment for these tears.
Treatment of shoulder pain:
Diagnosis: The treatment plan depends on the exact diagnosis of shoulder pain. Apart from a thorough history and clinical evaluation, the most important bedside evaluation is the evaluation of the shoulder with ultrasonography. In the majority situation, clinical evaluation and ultrasound evaluation together make a diagnosis. X-ray, CT scan, or MRI is needed only in a specific situations.
Red flags: Dangerous diagnoses like a tumor, fracture tendon tear, or infection must be diagnosed early for better treatment outcome.
Initial treatment of shoulder pain: These are mostly conservative with simple exercises, hot or cold compress, and analgesics. But in presence of tendon tear, exercises are avoided. Conservative management is effective in most situations, but the dangerous diagnosis must be ruled out.
Interventional pain management:
- Steroid injection in shoulder pain: Injection of depo-steroid is beneficial and recommended in arthritis, bursitis, or joint effusion. This depot steroid has minimal systemic side-effects with the recommended doses. But repeated steroid injections are harmful and are not recommended.
- Platelet-rich plasma (PRP) injection in the shoulder has replaced steroid injection in most types of shoulder pain. It is effective in tendinopathies, tendon tears, frozen shoulders, or early osteoarthritis of the glenohumeral joint. PRP injection is also called regeneration therapy because it can regenerate degenerated tendons, ligaments or joints. However, this process of regeneration is slow and takes almost one to two month/s for its optimum action. Also, PRP injections are effective in early diseases. In advanced conditions, the PRP injections are repeated at 3-8 weeks intervals.
PRP injections are always done under the guidance of ultrasonography to identify the pathological area and to inject exactly at the site where it is needed. For PRP injection, the patient’s own blood is taken in a kit which is then centrifuged in a special centrifuge machine, and the separated PRP is taken in the syringe for injection.
PRP injections are not effective if the patient’s platelet count is very low; if the patient is taking strong anti-platelet medicine like clopidogrel or taking a steroid for some reason.
- Radiofrequency or cryoneurolysis: In advanced condition or, if every treatment has been failed or if patients are not fit for surgery, sometimes pain-carrying nerves are blocked permanently with radiofrequency or cryoneurolysis. These nerves are only articular pain-carrying nerves not having other important functions. This is a highly specialized skill to identify these nerves and only a few hospitals have these facilities. In radiofrequency nerves are precisely heated at 60-degree centigrade and for cryoneurolysis nerve are cooled at minus 78-80 degrees centigrade. Cryoneurolysis is a very advanced mode of treatment and now it is available in Kolkata.
Surgery: Surgery is sometimes needed particularly for complete tendon tear, fracture, or advanced osteoarthritis when the shoulder joint replacement may be advised.