Description of the Rotator Cuff
The rotator cuff refers to a group of 4 muscles and tendons enveloping the shoulder joint. They arise from the scapular (shoulder blade) and insert onto the head of the humerus. The rotator cuff muscle function to assist movement of the shoulder joint, like lifting or rotating the arm. It also has a secondary function of keeping the shoulder joint stable.
Cause of Rotator cuff injury or damage
Rotator cuff tendon disorders/damage/injury can range from tendinitis (a strained or overused tendon) to a full-thickness tear. They develop because of 1 of 2 main reasons. Firstly, the rotator cuff can be damaged gradually over time from ‘wear and tear’ (usually in an older patient). Secondly, the rotator cuff can be damaged from a traumatic injury like a fall (usually in a younger patient).
When the rotator cuff is damaged or injured, the supraspinatus tendon is the most common tendon to be affected first, although other tendons like the infraspinatus and the subscapularis tendons can be involved as well with a more significant fall or over a longer period of time.
Rotator cuff or shoulder impingement essentially refers to rotator cuff tendinitis resulting from external compression (impingement) by the acromion, usually from repetitive overhead activities in an overhead sports athlete or someone who works with the arm over shoulder level for prolonged periods of time.
Symptoms of Rotator Cuff injury/damage
Patients with rotator cuff injury or degeneration mostly complain of pain in the front or side of the shoulder or upper arm. This pain of the affected shoulder will typically be felt while lifting the arm up, or when dressing and reaching the hand to the back. The affected patient will typically report ‘stiffness’ and a limited range of motion of the shoulder because of this pain. There may also be a pain at night with affected patients noticing difficulty sleeping on the side of the injured or painful shoulder. With more significant damage, patients may also complain of weakness and inability to lift the arm up to the functional position for activities of daily living.
In the young or middle age patient, the rotator cuff is usually injured due to a one-time traumatic injury like a fall onto the injured shoulder, as a result of repetitive overhead upper limb activities due to sports (baseball, various throwing sports, and racket sports) or an occupation (painting or construction). In the older patient, the patient’s rotator cuff tendon quality may deteriorate gradually due to ageing, and they may not experience any significant injury for the tendon to tear (degenerative tear).
Shoulder x-rays will usually be done in older patients. X-rays in this group of patients are useful to look for any evidence of bone spurs (a potential cause of the tendon degeneration/impingement), and any signs of pre-existing arthritis or degeneration of the shoulder joint.
Magnetic resonance imaging (MRI)
MRI scans are a much better option for assessing soft tissues problems like rotator cuff tears or tendinitis. The MRI scan also allows us to evaluate other soft tissue structures of the shoulder like the labrum and the cartilage, which can be injured together with the rotator cuff, especially with traumatic injuries to the shoulder.
For most rotator cuff injuries, especially in the setting of a rotator cuff tendinitis or a partial tear, the initial methods to treat these injuries are non-surgical; this can take weeks or even months, but the gradual improvement can potentially help patients regain pain-free motion, and gradually return to sporting activities of their choice over time.
Non-operative treatment involves:
- Resting the injured joint and modifying activities involving the shoulder. (limiting overhead activities and avoiding sports involving the use of the upper limb)
- Use of anti-inflammatory medications for short periods of time to bring down the acute inflammation and aid pain relief in patients with acute pain exacerbation.
- A course of physiotherapy that may include soft tissue massages & releases, stretching exercises, strengthening programs, and posture adjustment.
- Possible use of a steroid injection to control acute or persistent pain when other non-operative treatment measures do not work.
If non-operative treatment is not successful, surgical repair may then be recommended. Surgical repair will also be recommended at the outset for:
- acute traumatic complete full-thickness tears in a young active individual.
- large and retracted tears.
- tears that result in significant weakness and loss of function.
- tears that have resulted in persistent pain and disability for a long period of time.
Rotator cuff repair surgery is done in a minimally invasive manner. Dr Wee does these procedures in a keyhole, arthroscopic fashion, and as a day surgery or a single overnight stay under general anaesthesia. Depending on the complexity of the rotator cuff damage, a combination of 3 to 5 sub-centimetre keyholes will be made and utilized to perform the different steps of the procedure.
Performing rotator cuff repair using arthroscopic minimally invasive technique has the advantage of earlier recovery and less surgical trauma to the surrounding normal shoulder soft tissue. On top of that, the surgery is more accurate, and surgical incisions cosmetically more pleasing.
The arthroscopic procedure, (akin to a car servicing session) typically involves a few steps and processes:
- Cleaning and addressing any inflamed tissue. (bursectomy and articular debridement)
- Removing any bone spurs. (acromioplasty) to prevent bone spur impingement on the injured rotator cuff tendon; to allow more room for repaired tendon. (bone spurs are more common in the older patient)
- Repairing the torn rotator cuff using special rotator cuff suture anchors to re-attach the torn tendon to its original bony attachment. If the tendon is only partially torn, the damaged portions are debrided, and healing of the intact portions of the tendon is augmented with biologics (see advancement in rotator cuff surgery)
- Possible additional arthroscopic procedures are done at the same setting if the biceps tendon is damaged or the distal clavicle (collarbone) has degenerated.
After surgery, the operated arm will be placed in a sling for 4 to 6 weeks to minimise excessive movement of the operated shoulder to allow the repaired tendon to heal. The sling will have to be removed at least 3 to 5 times daily to allow simple exercises to begin immediately after surgery. Using the operated arm to perform simple activities like handling a handphone, writing, and eating can begin immediately after surgery with due care.
Physiotherapy is crucial in the post-operative recovery and will typically begin about 4 to 6 weeks after surgery once the sling is weaned off. Driving will be allowed once the arm is weaned off the sling. Physiotherapy aims to improve the range of motion and strength of the operated shoulder gradually. This will continue for 4 to 6 months after surgery. Most patients will recover a reasonable function and range of motion by 3 to 4 months after surgery, but physically demanding activities will usually be reserved until 6 months after surgery.