What is the Rotator Cuff?
The rotator cuff is a group of four tendons that lift and rotate the humeral head (ball part of the upper arm bone) and help contain the humeral head in the socket throughout movement. These tendons are called the supraspinatus, infraspinatus, teres minor and subscapularis. The tendons pass under the acromion (part of the shoulder blade) and are vulnerable to injury.
What is a Rotator Cuff Tear and how does it happen?
A tear of the rotator cuff can occur as a result of an injury or insidiously with degeneration (often as part of aging). The most commonly torn tendon is the supraspinatus which runs on the top of the humeral head and helps keep the humeral head in the socket as the shoulder is lifted by the deltoid muscle by the side or higher up.
A traumatic rotator cuff tear can result from a fall or a wrenching injury usually causing pain and weakness. Tears can be partial affecting only one tendon or full thickness tears affecting one or more tendons. Partial tears often cause pain but no significant weakness. They may progress to become full thickness tears. Full thickness tears may cause weakness, loss of function and pain.
Degenerate tears usually occur with daily “wear and tear” and as a result of the tendon weakening with age. These are often identified on MRI scan but tend not to cause any symptoms or dysfunction. If symptoms occur they may require treatment.
What are the symptoms of a cuff tear?
A rotator cuff tear may present with pain often in the front and side of the shoulder extending into the side of the arm. They frequently have pain at night and when trying to perform certain activities such as lifting or reaching upwards and outwards for items such as on the top shelf. There may be pain on tucking the shirt into the back of the trousers or putting an arm through a coat sleeve. Occasionally with larger tears there may be an ache with the arm simply hanging unsupported.
The pain can be avoided by not performing certain movements, however there may be weakness particularly when trying to perform daily activities at shoulder level or above.
How are rotator cuff tears diagnosed?
This is based on a careful history, establishing the mechanism of injury, and a physical examination. An ultrasound and/or MRI scan confirm the diagnosis and can report the site, size and nature of the tear and whether it has resulted in the associated muscle becoming thin and degenerate.
How are rotator cuff tears treated? Surgical VS Non-Surgical management
The natural history for partial articular sided rotator cuff tears is that some will heal, some will become smaller in size and some will become larger with time. Even asymptomatic full thickness tears of the rotator cuff may cause symptoms with time. A full thickness rotator cuff tear will not heal with time. Traumatic rotator cuff tears tend to become bigger with time.
Cortisone injections will often reduce the inflammation and pain allowing a pain-free window for physiotherapists to start therapy. Injections may result in a temporary relief of symptoms and it is often advisable not to have repeat steroid injections as they may weaken the tendon.
Physiotherapy aims at keeping the joint flexible, keeps the shoulder strong and may help improve symptoms. With large cuff tears special deltoid muscle recruiting physiotherapy exercises may be performed.
Surgery is recommended for traumatic cuff tendon tears. Surgery is also recommended for degenerate tears on which conservative (nonsurgical treatment) has failed. The aim of surgery is to restore strength and function and improve pain.
Surgery is generally performed arthroscopically (keyhole) but may be open (larger incision) or mini-open (smaller incision) using a combination of special stitches and bone anchors (stitches into the bone via a small mechanical device). Occasionally if the tear is very large and retracted (has pull backwards due to being left for a long time) a reconstruction may be required using a special patch graft between the tendon and the bone ends.
After surgery there is a period of immobilisation in a shoulder sling followed by a tailored physiotherapy rehabilitation programme by a specialist shoulder physiotherapist under the surgeons supervision to restore shoulder function and strength. Success of surgery is dependent on the size of the tear, quality of the remaining tendon tissue and often having better outcomes with earlier treatment.