Conservative Management
Basic, conservative therapy is generally sufficient to treat the condition. These include ice, NSAIDS and avoiding provocative maneuvers such as the bench press. The success rate of such therapy is upwards of 80%.
Modification of the bench press is a way to avoid undo stress on the distal clavicle during hyper-extension of the shoulder. Not only does this help alleviate symptoms, but it also allows the weight-lifter to return to weight training activities. The main idea is to prevent the elbows from descending beyond the level of the AC joint. One such way to do this is to place towels on the chest that restrict the distance of barbell descent during the exercise (this is known as the Honing technique). Performing the exercise with the hands closer together may also prevent extreme shoulder hyperextension.
Complete avoidance of the supine bench press is helpful. Alternatives may include the declined or inclined bench press and the cable crossover.
However, convincing a power-lifter to modify his or her weight training routine for a self-limiting, benign condition is often difficult. Also, many patients never present to the office and tend to push themselves through the pain. Continuing the exacerbating maneuver for a period of time will result in self-surgery, as the distal clavicle will lyse on its own and ultimately resect itself.
Surgical Management
Distal clavicle resection (Mumford procedure) has long been the surgical treatment of choice for this condition. The procedure may be performed either open or arthroscopically. As with any other treatment modality, open versus arthroscopic distal clavicle resection have their pros and cons.
Open Mumford
The advantages of the open procedure include improved visualization allowing an adequate amount of the distal clavicle to be removed. The disadvantages are increased surgical trauma that prevent early range of motion exercises. Arthroscopic procedures require a bit more experience and precision. In other words, technical inexperience with arthroscopic procedure is an indication for the open procedure.
There are two approaches to the distal clavicle that are most commonly used: the strap approach (vertical incision that utilizes the lines of Langer for improved cosmesis) and the horizontal approach. The decision to use either approach is usually as simple as the surgeon's preference.
Following resection, there are several options for closure. One method requires suturing the deltoid fascia to the AC joint capsule, thereby eliminating dead space. Another is to partially detach the coracoacromial ligament from the acromion and transfer it to the distal clavicle, providing more stability for the athlete.
In general, active range of motion exercises are delayed until at least one week has passed after surgery.
Arthroscopic Mumford
The advantages of the arthroscopic Mumford procedure are minimal scarring, less soft tissue dissection and a quicker recovery. Early active range of motion exercises can be started within the first week after surgery. The main disadvantage is that less bone can be removed arthroscopically.
There are two basic arthroscopic approaches to distal clavicle resection. The first is the superior approach and the second is the subacromial approach.
The subacromial approach preserves the integrity of the superior AC ligament which diminishes the possibility of post-operative instability. This also allows for visualization of any other shoulder pathology. However, this approach requires removal of the subacromial bursa.
The superior approach is mainly used to avoid trauma to the subacromial space, especially if no pathology is expected in that area. It also involves disruption of the superior AC ligament, which may necessitate removal of more bone than the subacromial approach. Removal of more bone is required to prevent abutment of the acromion into the distal clavicle because the joint is less stable after removal of the superior AC ligament.
In general, postoperative therapy involves early passive range of motion such as pendulum exercises. If the procedure was open, delay active range of motion until after the first week. If it was arthroscopic, active range of motion can begin within the first week.
Outcome
As outlined above, distal clavicle osteolysis is a self-limiting condition that will resolve within 2 years , but resof activity modification. Some patients experience either a return of symptoms or contralateral involvement if the inciting maneuver is continued.Both surgical and conservative treatments have excellent results, especially if the etiology is atraumatic. The traumatic version may have a slightly increased risk of unfavorable results, such as continued pain.
Complications
As with any surgical procedure, certain risks are always present. These include infection, anesthesia, and neuromuscular injuries that may result from surgical dissection. Surgery around the clavicle always involves a risk to the subclavian vessels, brachial plexus and supraclavicular nerves that reside in the posterior triangle of the neck.Limited postoperative mobility and/or excessive sling usage may result in frozen shoulder (aka adhesive capsulitis) that may permanently impede mobility of the glenohumeral joint. It is therefore necessary to start range of motion exercises in the early postoperative period to prevent this complication.
Pearls and Pitfalls
Controversy
The actual pathogenesis of distal clavicle osteolysis is controversial. However, it is now widely accepted that repetitive microtrauma is most likely involved.A more recent controversy involves the amount of clavicle resection that is required to alleviate symptoms. In the open procedure, it has generally been routine to resect 1-2 cm of the distal clavicle. However, it is nearly impossible to resect that amount of clavicle in the arthroscopic procedure (often less than 1 cm). After much debate and research, it is now generally accepted to resect at least 4mm of clavicle in order to provide relief of symptoms. In general, enough of the clavicle needs to be removed in order to allow full range of motion of the shoulder without impingement of the acromion onto the clavicle.
References
DeLee, Jesse C., et al. "Osteolysis of the Distal Clavicle". DeLee and Drez's Orthopaedic Sports Medicine, 3rd Edition. Philadelphia. Elsevier, Inc. Copyright 2010.Owens, Brett D. "Distal Clavicle Osteolysis". Medscape Reference. Keenan, Mary Ann. Updated 15 July 2011. Accessed 14 Oct 2011 <http://emedicine.medscape.com/article/1262297-overview>.
Schwarzkopf, R., et al. "Distal Clavicular Osteolysis: A Review of the Literature". Bulletin of the NYU Hospital for Joint Diseases. 2008. Volume 66. pp94-101.
