There are four muscles around the shoulder which form the rotator cuff. As the name suggests, the rotator cuff rotates the shoulder joint. They are the supraspinatus, infraspinatus, teres minor and subscapularis muscles.
Each of the four muscles moves the joint in a different direction. If one of the tendons attaching these muscles to bone is torn, you will lose the movement that specific muscle would have provided to the joint.
The rotator cuff muscles also have another important function – to keep the ball centered in the socket of this ball-and-socket joint. If one of them is torn, an imbalance can develop which could lead to rotator cuff arthropathy – a type of arthritis in the shoulder.
Two types of tears are encountered. The first, an acute tear is due to trauma like a fall on an outstretched arm.
The second develops gradually over time and is caused by diminished blood supply in the area where the tendon attaches to the bone. Blood supply to this area gets less with age and smoking can make it worse. The tendons then weaken and can wither away from the bone.
Diagnosing a rotator cuff tear starts with a good patient history and a thorough examination. An ultrasound is a very useful tool to diagnose a tear. If it is unclear on the ultrasound a MRI scan can be requested.
Treatment includes painkillers, anti-inflammatories and physiotherapy.
Cortisone injections may be used once to utilize the anti-inflammatory effect of the cortisone. Repeated injections should be avoided, however, as this might compromise the quality of the tendon.
Treatment depends on the age of the patient and the type of tear. An acute tear will need surgery to repair. If a tendon tear does not respond to conservative treatment it is best to repair it.
Certain factors may influence the success of a repair. These include the quality of the muscle, the retraction of the tendon, the quality of the tendon and the body mass index (BMI) of the patient.
A complete tear of the rotator cuff will not heal and needs surgery.
There are two types of operations one can do – open surgery or arthroscopic surgery.
In my practice mostly arthroscopic (keyhole) surgery is done. This has the advantage of being less invasive and allows the surgeon to evaluate the whole joint.
Tiny 3-5mm incisions are made and instruments are passed through, including a camera which becomes the ‘eye’ of the surgeon by projecting a picture of everything it sees onto a screen.
The rotator cuff tear is evaluated and then repaired. Small anchors are placed in the bone and sutures from the end of the anchor are used to pull the tendon back onto the bone.
A shoulder sling will be worn for three weeks after the operation. An occupational therapist should advise you on how to go about your daily life for this period while your shoulder is protected in a sling.
After three weeks your sling will be taken off and an ultrasound will once again be done to evaluate the repair. The good news is that 90% of rotator cuff repairs are successful.
Once this is confirmed on ultrasound, you will be asked to see a physiotherapist. He or she will then start to mobilize your rotator cuff. This will take place over the next three to nine weeks. It may take up to six months for the shoulder to recover completely.
Complications are rare and may include a failed repair due to poor tissue quality, infection, or post-operative frozen shoulder.