Distal Clavicle Excision, also known as the Mumford procedure, is a surgical intervention designed to relieve chronic shoulder pain originating from the acromioclavicular (AC) joint. This procedure involves the precise removal of a small segment of the collarbone’s end. The goal is to eliminate painful friction between the bones, which typically occurs due to degeneration or injury. Orthopedic surgeons recommend this solution when non-surgical treatments fail to provide lasting relief.
Understanding the Acromioclavicular Joint
The shoulder is a complex structure involving three main bones, and the acromioclavicular (AC) joint is where two of these meet: the distal end of the clavicle, or collarbone, and the acromion, which is the highest point of the shoulder blade. The AC joint is a small, plane-type synovial joint that allows for gliding movement and helps transmit forces from the arm to the rest of the skeleton. It is stabilized by a capsule and several strong ligaments.
This joint plays an important role in the overall range of motion of the shoulder, particularly during overhead and cross-body movements. Because of its location, the AC joint is frequently subjected to considerable stress, making it susceptible to wear and tear over time. As the protective cartilage within the joint wears down, the bare bone surfaces can begin to rub together, leading to inflammation and pain.
Conditions Requiring Distal Clavicle Excision
A surgeon typically recommends a Distal Clavicle Excision when shoulder pain localized to the AC joint has not responded to conservative treatments like rest, anti-inflammatory medication, or corticosteroid injections. The two main indications for the Mumford procedure are AC joint osteoarthritis and distal clavicle osteolysis. Both conditions cause significant pain and tenderness directly over the joint.
AC Joint Osteoarthritis
Acromioclavicular joint osteoarthritis is a common degenerative condition where the cartilage cushioning the joint erodes, often seen in older individuals or following prior trauma. This leads to bone-on-bone friction and the formation of painful bone spurs. Post-traumatic arthritis following an AC joint separation or fracture is another form of joint degeneration that may necessitate this surgery.
Distal Clavicle Osteolysis
Distal clavicle osteolysis, sometimes referred to as “weightlifter’s shoulder,” involves the breakdown and dissolution of the bone at the end of the clavicle. This condition often affects athletes who engage in repetitive, heavy overhead or compressive activities that overload the joint. Symptoms for all these conditions include pain with overhead lifting, reaching across the body, or tenderness when touching the joint.
How the Excision Procedure is Performed
The Distal Clavicle Excision is performed to create a permanent space between the end of the collarbone and the acromion, eliminating the painful bone-on-bone contact. The procedure is typically performed while the patient is under general anesthesia. The critical step involves removing a small, precise segment of the distal clavicle, usually between 6 and 10 millimeters.
Arthroscopic Technique
The preferred and more common approach today is the arthroscopic technique, a minimally invasive procedure that utilizes an arthroscope and specialized instruments inserted through small incisions. The surgeon visualizes the joint on a monitor while using a surgical burr to shave off the end of the clavicle. The arthroscopic method is favored because it results in less trauma to the surrounding soft tissues and promotes a faster initial recovery.
Open Procedure
An alternative is the open procedure, which requires a larger incision directly over the AC joint. While the open technique is still used in certain complex or revision cases, it is less common for an isolated Mumford procedure. In both methods, the goal is to ensure adequate removal of the bone to prevent re-impingement, while carefully preserving the surrounding stabilizing ligaments. The surgeon closes the incisions with sutures or adhesive strips once the space is successfully created.
Recovery Timeline and Rehabilitation
Recovery from a Distal Clavicle Excision relies heavily on a dedicated rehabilitation program to achieve a successful outcome. Immediately following the surgery, the patient’s arm is typically placed in a sling for comfort and protection, which may be worn for the first two to four weeks. Pain management is a focus during this initial period, and patients are encouraged to move their elbow, wrist, and hand to prevent stiffness.
The early rehabilitation phase, often starting within the first week, focuses on restoring passive range of motion. A physical therapist guides the patient through gentle, controlled movements that protect the surgical site. This phase aims to prevent the formation of scar tissue and stiffness, which can limit long-term mobility.
As healing progresses, typically around four to eight weeks post-operation, the patient moves into the strengthening phase. This involves starting active range of motion exercises, followed by light strengthening activities targeting the rotator cuff and scapular muscles. Return to functional and sport-specific activities generally occurs between three and six months after the procedure. Adherence to physical therapy is paramount to rebuild strength and ensure a full return to normal shoulder function.