Acromioclavicular Joint Injury - Tossy Injury - AC Joint Rupture - Shoulder Surgery
Anatomy: Acromio-clavicular joint
In addition to the main shoulder joint, e.g. the humeral head and the socket in which it moves, there is a small but very important joint, called the acromio-clavicular joint or in short AC joint.
The AC joint is the articulation (connection) between the outer end of the collarbone (clavicle) and the acromion (part of the scapula that forms the highest point of the shoulder); the intervertebral disc, the so-called "discus" functioning as a buffer, is located between the cartilage surfaces. The AC joint, a very tight joint, is surrounded by a strong joint capsule. It is additionally stabilized by the coracoclavicular ligaments.
Consequences: Acromioclavicular joint injury
Depending on the extent of the force, in an injury one or more of the stabilizing ligaments are overstretched to a point of a completely torn joint capsule.
Consequences of a coracoclavicular injury are a more or less strong instability of the joint with corresponding deformity of the outer end of the collarbone. The severity of the injury is classified into grades, whereby the most commonly used classifications are those according to Tossy (I-III) and Rockwood (I-VI).
Symptoms: Acromioclavicular joint injury
The injured person generally complaints about pain that is especially strong when moving the arm. Most often, the affected individual will keep the arm in a protective posture, typically supporting the injured arm with the hand of the healthy arm. In addition to swelling in the shoulder region, the outer end of the collarbone often protrudes through the skin, and there is possibly also a displacement toward the back.
Emergency measures: Acromioclavicular joint injury
An immediate measure is to stabilize the arm in a bandage or sling in front of the stomach, which helps to reduce the pain. As with all other acute injuries, applying an ice pack will lessen the tissue swelling and at the same time reduce the pain. It is, however, essential to immediately consult a physician.
Diagnosis: Acromioclavicular joint injury
An accurate diagnosis includes in addition to the patient fully describing the incident, a comprehensive examination of the shoulder. Most often this also requires x-raying the shoulder to rule out a possible fracture. in addition to the patient description of the accident.
A more accurate indication of the severity of the coracoclavicular injury (Tossy I-III and Rockwood I-IV), can be obtained by so-called load imaging, which allows the orthopedist to compare the joints on both sides. The extent of the high level of the clavicle under tension is a direct measure of the severity of the injury. Alternatively, an ultrasound will show the instability of the injured joint and a magnetic resonance imaging (MRI) identifies the injured ligament.
Conservative treatment: Acromioclavicular joint injury
In minor injuries of the acromioclavicular joint (Grade I and II), the coracoclavicular structures are merely slightly overstretched and/or ruptured. Consequently there is only slight instability of the joint, which should be treated conservatively, i.e. non-operative.
As a first measure, the shoulder should be immobilized with a supportive bandage to relieve the pain. Additionally, ice packs and possibly medications reducing the swelling (e.g. diclofenac, ibuprofen) are initially helpful. Physiotherapy can also help the healing process.
In cases of a minor injury (Tossy I-II, Rockwood I-II), the patient can return to light training after the pain has lessened, provided, however, the type of sport he or she participates in is not too stressful for the shoulder.
To facilitate healing of partially injured ligaments after having sustained a moderate acromioclavicular joint injury, the patient should not return to active sports until six to eight weeks after the incident. If the patient participates in contact or high risks sports activities, he or she should not return to his/her regular sports activities until 12 weeks after the incident. With a rupture of all ligaments (Grade III and above), surgical treatment is highly recommended; the advantages and disadvantages of different treatment methods must, however, be weighed individually.
Surgery: Acromioclavicular joint injury
The anatomical restoration of the joint structures in young and physically active people must be more comprehensive since otherwise the function of the shoulder may remain limited.
Additionally, the development of premature degenerating of the shoulder joint (Osteoarthritis) has to be taken into consideration. Finally, there is also the cosmetic aspect, since some patients consider a clearly protruding collarbone as bothersome.
Whether an operation is meaningful in case of a higher grade of injury (Tossy III, Rockwood III - IV), depends on the each case and should definitely be discussed with a shoulder specialist.
Surgical techniques: Acromioclavicular joint injury
schulgelgrThe aim of surgery is the precise anatomical recovery of the injured, unstable acromioclavicular joint. The principle of the surgery is based on the setting the shifted parts of the joint back into place. Thereafter, the joint must be temporarily secured so that the ruptured capsule ligaments heal and can assume their stabilizing function again.
To achieve the best results, it is essential that such surgery is performed as soon as possible after the injury has been sustained, meaning within two weeks after the accident. After a two-week period, the injured ligaments cannot heal sufficiently and must be replaced by a tendon transplant.
Previously this surgery was performed by open surgery in which a plate was inserted and wires or bioresorbable suture materials were used. These techniques had partially significant disadvantages since a second surgery was necessary to remove the implants.
Today shoulder specialists are able to perform a minimally invasive - arthroscopic surgery (key hole surgery). This technique requires merely four approx. three millimeter incisions, through which an optic with a mini-camera and the finest surgical instruments are inserted.
The actual internal fixation is done with two arthroscopic suture systems, which are secured with small titanium plates (Tight Rope; Arthrex Fa). Also here it is essential that the surgery is done within the first two weeks (acute phase) after the injury took place. Again, a quick and accurate diagnosis is necessary within the first week after the injury has occurred, so that the most effective method can be used.
Already after two weeks, an acromioclavicular joint separation turns into a chronic injury. The injured ligaments cannot heal sufficiently. For this reason, after more than two weeks past the time of the injury, an autologous ligament (body's own tendon) is used to reconstruct the ligament structures (like in a cruciate ligament surgery). This surgery is also supported arthroscopically and is minimally invasive.
Arthroscopic stabilization surgeries for an acromioclavicular joint injury are done under general anesthesia. Generally, a short hospital stay of two nights is necessary.
Postoperative: Surgery acromioclavicular joint injury
If an acromioclavicular joint (AC joint) injury was treated surgically, the shoulder should be protected for about two weeks with a functional bandage. An early physiotherapy will assist the healing process and prevent a frozen shoulder. Activities above shoulder height and more intense activities and movements, should be avoided for eight to ten weeks. High-risk and high-impact sports should be avoided for four to six weeks.
Specialists: Acromioclavicular joint injury
For an optimal treatment of an acromioclavicular joint injury, the shoulder experts at the Klinik am Ring are particularly well-qualified. Stefan Preis, M.D. and Jörg Schroeder, M.D., senior physicians at the Practice and Department of Orthopedics and Sports Traumatology at the Klinik am Ring in Cologne, specialize together with their team in the treatment of knee and shoulder disorders. In 2004, they founded the WEST GERMAN SHOULDER KNEE & CENTER, Cologne. The team consisting of eight specialists treats more than 10,000 patients per year. The team performs more than 2500 knee and shoulder surgeries per year of which are meantime several hundred surgeries are surgeries of the acromioclavicular joint.