Acromioclavicular Separation

Acromioclavicular or AC Joint Injury is a common injury which results from falling directly onto the point of the shoulder and is most commonly seen following a sporting accident. Mild injury results in pain at the top of the shoulder, short term restricted use of the arm, and does not require surgery. More severe separation can result in persistent symptoms which may include restricted function of the arm and will often require surgery.

Anatomy [See Fig.1]

The area of interest lies just on top of the shoulder joint itself and involves the connection between the collar bone (clavicle) and a part of the shoulder blade called the acromion. The AC joint itself is a small joint which lies between the very outer tip of the collar bone and the acromion. It is made up of a small piece of cartilage sandwiched between the two bones and covered in a sack called the capsule. Relatively weak ligaments span between the two bones also. The collarbone is held firmly in place by these ligaments and also a set of much stronger ligaments which run between the under surface of the collar bone and a projection of bone from the shoulder blade called the coracoid. These are called the coracoclavicular ligaments.

Fig. 1 AC joint area anatomy

Structural damage and consequences

In a mild injury there is a simple sprain of the ligaments and capsule of the AC joint (Grade I),or a partial tearing of the ligaments allowing slight separation of the AC joint (Grade II). [See Fig 2 & 3]

Fig.2 Grade I

Fig.3 Grade II

These injuries result in pain and local swelling and in the case of Grade II injuries a permanent increase in the bump of the outer end of the collar bone. Grade I and Grade II injuries can be treated in a sling for a few weeks to allow pain to settle and thereafter by a physiotherapy programme to ensure full movement of the shoulder is regained and to restore strength.

Occasionally persistent pain from these injuries will require a small surgical procedure at a later stage. This will usually take the form of resection of the outer end of the collar bone and the associated capsule and ligaments of the AC joint.

Fig.4 Grade III

A severe AC joint injury involves complete rupture of both the AC joint ligaments and the coracoclavicular ligaments. This results in a wide separation of the AC joint with elevation of the collar bone and subsequently a prominent bump and change in contour of the shoulder (Grade III) [See Fig. 4]

These ligaments do not heal by themselves and ongoing problems can occur.
These may take the form of :

• persistent pain in the area
• clicking or catching with movement of the shoulder in certain positions
• reduction of full strength in the arm
• restriction in the ability to carry out sporting activities particularly of a throwing nature, or work place duties where there is a requirement to frequently lift or manoeuvre objects at or above the shoulder height.

Treatment

Grade III AC separation can be treated with or without surgery and the decision regarding this needs to be individualised.

Non operative treatment for this injury is similar initially to that of Grade I or II injuries with the use of a sling until pain settles and thereafter physiotherapy to restore movement and strength. It may take 6-8 weeks for the pain to settle sufficiently to allow normal use of the arm and up to 3 months before adequate strength returns for competitive sport or overhead physical work. The prominent bump and change in shape of the shoulder will not change.

Following this form of treatment adequate movement and strength with minimal or no pain may result. If so, the ability to return to previous work or sporting activities will be possible. In other cases however significant persistent pain or feelings of clicking or catching or reduced strength will prevent return to previous activities.

Surgical treatment for this condition is undertaken when this situation arises. At this stage the operation consists of a reconstruction of the coracoclavicular ligament with a graft of some kind and the use of an artificial implant device to provide the initial strength.

Surgery is much more successful for Grade III AC separations when performed early (within 2 to 3 weeks of the injury). When done early the surgery is less complicated and results in the natural healing of the coracoclavicular ligaments rather than requiring a graft. There is less reliance on the ongoing strength of an artificial implant.

It is recommended to consider having the surgery performed early after the injury in people who engage in throwing or contact sports or those who perform overhead or heavy manual work.

In most others it is reasonable to take a non operative approach to this injury initially and undergo the surgery only if persistent symptoms become unacceptable. There is a higher chance that people with lower demands will not require the surgery.

EARLY SURGERY: Acromioclavicular repair

Fig. 5 Metal plate fixation

SURGERY AFTER 2 to 3 WEEKS: Acromioclavicular Reconstruction Surgery

The surgery for a reconstruction of the AC joint involves a vertical incision of 3-4 cm over the front of the shoulder. The outer 1cm of the prominent collar bone is cut off and the AC joint thus is replaced with some scar tissue once healing has occurred. The strong coracoclavicular ligament which normally holds the collar bone down is reconstructed using either a hamstring graft harvested from the leg or using a small ligament which is nearby at the top of the shoulder.

An implant is then added to provide initial strength to the area while the grafted ligament matures. The implant is either made of a synthetic ligament substitute or a metal plate as above. The implant is designed to remain in the body permanently but can be removed if necessary. The larger metal plate always requires removal, usually at 3-4 months following the operation. A dissolving stitch is used at the end.

What to expect after the surgery

(The following comments apply to both the early repair and full reconstruction surgery.)

A general anaesthetic is used and occasionally a local nerve block injection to numb the area. The operative area is initially covered with a bulky dressing and a sling applied. Pain will be present but by evening should be well controlled with tablets.

Discharge from hospital is usual the following morning but may be in the same evening following a morning operation. The bulky dressing is taken down and the waterproof dressing replaced if soiled. This should be left in place until the post operative review by Mr. Dallalana and the date of this will be given to you at the time surgery is booked (10 to 14 days post surgery). You may shower but try not to directly soak the dressings. The wound should be kept dry until review.

A physiotherapist will see you prior to discharge and instruct on simple exercises to do and how to manage the sling. In general it should be used when standing or walking. It may be taken off for exercises, cleaning and when resting at home as well as at night.

Rehabilitation

The goal of the early recovery period is to limit excessive movement of the shoulder and in particular any extra load on the arm to reduce the strain through the repaired area. Any weight held in the hand or lifted with the arm has a tendency to separate the AC joint which is working against the goal of the surgery.

The first 6 weeks is important for healing and use of the arm should be minimized. Avoid sports and loads heavier than those required for general living. You should not raise the arm above the level of the shoulder during this time. You should not run during this period and it is not permitted to drive when using a sling. Use of the sling can be gradually reduced as tolerated after the first 2 weeks post surgery.

From 6 weeks after the surgery you will be permitted to move the arm in any direction as you please. It is usual to require some physiotherapy and home exercises to regain full movement of the shoulder and to commence a strengthening programme. Swimming and running may commence after this time if comfortable.

Sporting activity and heavy manual labour may commence from the 3 month point if adequate strength has been regained.

Prognosis

In the majority of cases full use of the arm is expected.

Since a lot of force passes through a relatively small area Grade III AC joint separation is notoriously difficult to treat surgically. It is normal for the collar bone to ride up a small amount following the surgery which has no ill effect, however on occasion the graft may not take and/or the implant fails resulting in the collar bone elevating to a similar height as it was before the surgery. In these situations it is not always necessary to repeat the reconstruction as some degree of healing has often occurred and symptoms may not warrant it.

Occasionally, in the situation where the surgery is performed within the first 2 weeks of the injury and the collar bone is simply brought back down and held in place with the implant, pain due to injury to the AC joint itself which has not healed properly may require a second small operation where the outer end of the clavicle is removed. This can be done through a keyhole technique and does not require a prolonged recovery period.

Possible complications

Complications are rare from this type of surgery.

Some complications which are related directly to the shoulder:

• Bleeding under the skin related to the incision may lead to local bruising. This bruising may run down the arm and across to the chest area. It is common, goes away in a couple of weeks, and does not require treatment.
• Infection may occur and may be suspected by an increase in pain, fever, nausea and generally feeling unwell. The surgical wounds may be surrounded by reddening of the skin and may discharge fluid, blood or pus. There may be a foul odour. Infection around the small wounds only will settle without consequence after treatment to the area such as removing the stitch, local dressings and possibly antibiotic tablets. Infection deep within the operated area is very rare however more serious when it occurs, and may require surgical washout of the AC joint and local area or removal of any metal or graft material. A prolonged course of antibiotics is required.
• Stiffness of the shoulder joint itself due to the period in a sling may occur despite appropriate rehabilitation with exercise and physiotherapy. It is uncommon. On occasions a brief procedure under anaesthetic may be required to free up the shoulder.
• It is common following this type of surgery to have a small numb patch over the top of the shoulder due to stretching or damage to a small nerve in the area of the incision. It does not always resolve with time and is of no particular consequence. Damage of important nerves which pass near the surgical area into the arm is possible however extremely rare.
• Injury to major blood vessels passing to the shoulder is also possible. Some large vessels pass directly beneath the collar bone and are open to injury during surgery in this area. If this happens, surgery to reconstruct the artery or vein could be needed. Permanent loss of muscle function in the arm or hand may occur.

Some complications of a more general nature:

• The surgery is carried out under general anaesthetic which is very safe, however on very rare instances a problem relating to the airway, lungs or heart and circulation may occur.
• An intravenous line is always required, and occasionally an additional line into a small artery near the wrist to monitor blood pressure. Its use may result in pain or bruising at the point of entry, and rarely an infection or thrombosis of the vein or artery.
• Blood clots in the veins of the calf and / or leg (Deep Venous Thrombosis) may occur despite the surgery not involving these areas. It is very rare but when large can pose the threat of movement of the clots within the veins to the lungs (Pulmonary Embolus) and this can be serious or even fatal.
• Your anaesthetist will discuss the use of an injection above the shoulder near the neck (Nerve Block) to help ‘deaden’ the shoulder and arm for approximately 24 hours to help control pain. There are complications reported relating to this including bruising and nerve damage.
• Allergy to the antibiotic which is routinely used immediately prior to the surgery can occur. This most often causes a rash. Very rarely when serious an allergy can cause obstruction to the airway or reduced blood pressure.
• Pain killing tablets will be issued at discharge from hospital to use as needed. Reaction to the tablets may occur and can include a rash, nausea, stomach pain, dizziness or light-headedness. Stop them and see your local doctor for alternatives if needed.

In case of problems:

1. Pain control – contact local GP initially
2. Signs of infection (persistent increase in pain, wound discharge beyond 2 days following surgery, foul odour, fevers) – contact Mr. Dallalana via the rooms or through the hospital where you had your surgery if out of business hours. GP may be contacted for review concomitantly.
3. Tingling in the arm or hand or calf pain – contact Mr. Dallalana via the rooms or GP if convenient.
   Contact the hospital where you had your operation if out of hours.
4. numbness or persistent coolness in the hand or fingers – attend nearest emergency department
5. Shortness of breath, severe lack of energy or sudden high fevers with chills or shakes – attend nearest emergency department.

Non-urgent matters should be listed for discussion at the next review with Mr. Dallalana or alternatively queries can be directed via e-mail at This e-mail address is being protected from spam bots, you need JavaScript enabled to view it or by calling the rooms.

Certificates can be obtained at review or by your GP at other times.

• Please contact Mr Dallalana's rooms if you require further information.