Treatment of Shoulder Instability

What is the shoulder joint?

The shoulder is a remarkable joint and quite complex. It allows a wide range of motion and is the most mobile joint in the body. It is a ball-and-socket type joint, consisting of the humerus (upper arm bone) and the glenoid (shallow cavity) of the scapula (shoulder blade).

Stability of the joint is a result of:

  • Shoulder ligaments that run from the humerus to the scapula.
  • The labrum which is a type of cartilage tissue that encircles the bony glenoid, deepening the cavity of the joint.
  • Tendons of the rotator cuff muscles that runs from the scapula to the humerus and stabilize the upper part of the humerus.
  • Negative pressure inside the shoulder joint that acts like a suction cup.
  • The shoulder becomes unstable when these structures are not able to keep the humeral head onto the glenoid.

There are two main groups:

  • Traumatic: The most common is from an injury.
  • Atraumatic: Normally there is no injury and is a result of weak ligaments / tendons because of ligament laxity or inherited diseases like Marfan’s or Ehlers-Danlos Syndrome.

 

With an injury, the humeral head can be forced out of the socket causing either stretching or tearing of the ligaments,capsule, and labrum. After reduction of the joint, this can heal in a stretched out / loose position, or the labrum detaches from the bone. Sometimes, especially in people over 40, there is also damage to the rotator cuff tendons. There may also be damage to the back of the humeral head causing an indentation, called a “Hill-Sachs” lesion.

The most common dislocation is where the humerus comes out towards the front (anterior dislocation) normally because of contact sports. Much more uncommon, is where the shoulder dislocates towards the back (posterior dislocation), which is normally a result of an electric shock or an epileptic fit.

How is instability diagnosed?

A complete history and physical examination will be done – this includes assessing range of motion, strength, and tests to assess looseness or laxity of the shoulder.

You might need to have further tests done to confirm the rotator cuff injury / tear.

These tests include:

  • X-ray of the shoulder.
  • CT (Computed tomography) scan.
  • Magnetic resonance imaging, sometimes with injection of dye into the shoulder.

Treatment of shoulder instability:

Treatment of a shoulder dislocation after reduction includes the following:

  • Rest / immobilisation for a period in a sling.
  • Pain medication, which is normally a combination of Paracetamol and anti-inflammatories.
  • Physiotherapy to strengthen the rotator cuff and shoulder muscles.
  • Activity modification – avoid activities that causes subluxation / dislocation.
  • Surgery.

 

Surgical treatment of shoulder instability:

It is important to remember that not all shoulder instability needs to be fixed by having surgery. Surgery is normally reserved for the following:

  • Shoulder dislocation in an older patient associated with a rotator cuff tear.
  • Recurrent dislocations especially with ‘normal activities’ like dressing / sleeping.
  • Dislocation in a patient under 20 years of age.

 

Type of Surgery:

Surgery for instability can be done arthroscopically through small incisions most of the time. Sometimes it is necessary for open surgery. The most common surgery performed for shoulder instability is the attachment of the labrum known as a Bankart repair.

With a Bankart repair, a camera is placed into the shoulder joint and through keyhole surgery the damaged cartilage,loose and abnormal labrum are removed. The labrum is then mobilised and fixed to the front of the shoulder with multiple anchors.

If there is significant bone loss, a Bankart repair this is not possible. To address the bone loss, a bone from the front of the shoulder blade, called the coracoid process with its attached muscles are screwed to the front of the socket (glenoid). This is called a Latarjet procedure.

General risks of surgery:

  • Shoulder stabilisation surgery is done using general anaesthesia, where a patient is put to sleep. Unexpected death from an anaesthetic is very rare.
  • Antibiotics are routinely used during surgery to prevent infection – some patients may have an allergic reaction or anaphylaxis.
  • Wound infection.
  • Bleeding in the wound with haematoma (big collection of blood) formation.
  • Pain / numbness around the incision.
  • Allergies to antiseptic solutions used to clean the surgical site.
  • Allergies to sutures and / or dressings.
  • Deep vein thrombosis – there is always a risk of DVT with surgery.
  • Nausea and vomiting after surgery.

 

Specific Risks of Surgical Repair of Instability:

  • The patient will be asked to wash the shoulder daily for 3 days before the surgery with a shampoo called Benzoyl peroxide to prevent an infection by an organism (Cutibacterium Acnes), living in hair follicles which can cause a low-grade infection with shoulder surgery – this might cause an allergy.
  • The patient is positioned in either the ‘beach chair’ position for the surgery or lying on the opposite side (lateral decubitus), with the operated arm in traction. In the” beach chair” position, the patient is in a “seated” position. Because this can lead to a drop in blood pressure, the anesthetist will insert an arterial line into the opposite arm to monitor the patient’s blood pressure very carefully.
  • The anesthetist will discuss a nerve block to help with pain relief, which will be done after the patient goes to sleep. The nerve block normally lasts for about 12 hours – during this time the arm will feel very heavy and numb.
  • During arthroscopic surgery, a pump is used to control bleeding in the shoulder. This results in swelling of the shoulder that can be quite significant, but usually settles overnight after the surgery.
  • Injury to the nerves around the shoulder.
  • Despite a good repair of the labrum, further dislocations are possible if there is another significant injury.
  • After surgery, the patient is placed in a shoulder sling for 6 weeks.
  • Because the shoulder is immobilized for a period of 6 weeks, stiffness is common after the surgery. It will take a long time for the movement to return. Persistent stiffness may need further surgery.
  • The surgery might not work and there might be further dislocations.
  • Ongoing pain and discomfort.

 

Recovery after Surgery:

The patient will wake up in the recovery room and with a shoulder brace in position on the operated arm. The nurses in the recovery room will monitor the patient’s recovery by regularly checking the vital signs (pulse, blood pressure etc), pain levels and consciousness.

When the patient gets home, he / she will need to continue using the shoulder brace all the time, including when going to sleep. Oftentimes it is easier to sleep in a recliner after the surgery.

The patient will be discharged home with strong pain medication. It is better to use the stronger pain medication only if normal pain medication like Paracetamol is not effective.

It is important to keep the surgical area clean and dry and to keep the wound dressings intact. The dressings on the shoulder should be waterproof and if the dressings get wet, it needs to be changed.

The patient will be supplied with a follow-up date for the removal of sutures and a wound review.

A physiotherapist will see the patient in hospital and will supply them with some initial exercises. These are very gentle exercises that the patient needs to do for the first 6 weeks. It is important to book an appointment with a physiotherapist of choice to continue with rehabilitation after 6 weeks.

Recovery after surgery is different for every patient. It is very important follow instructions from the healthcare team. Recovery is a slow and gradual process and can take up to 12 months. It is common that there will be some discomfort and stiffness after surgery. The patient will be advised about return to sport and other activities.

Please contact the surgery immediately if you have any of the following:

  • Any redness, swelling, bleeding or drainage from your incision site.
  • Any fever or chills.
  • Any increase in pain around the incision site.
  • Any tingling / numbness in arm.

Please find some additional information by following the links below:

The following link have wonderful animation:

Latarjet Shoulder Repair