Subacromial decompression is a common surgical procedure used to alleviate chronic shoulder pain that has not responded to non-surgical treatments. The operation is designed to increase the physical space within the shoulder joint, preventing the pinching of soft tissues. This intervention is often completed using minimally invasive techniques to restore comfortable movement and function.
Understanding Shoulder Impingement
Subacromial decompression is typically recommended for shoulder impingement syndrome, also known as subacromial pain syndrome. The shoulder is a highly mobile ball-and-socket joint, stabilized and powered by the rotator cuff. These tendons, particularly the supraspinatus tendon, pass through a narrow passageway beneath a bony arch called the acromion, which is the outer part of the shoulder blade. The space between the acromion and the rotator cuff tendons is called the subacromial space. Within this area is the subacromial bursa, a fluid-filled sac that acts as a cushion to allow the tendons to glide smoothly during arm movement.
Impingement occurs when this space narrows due to inflammation of the bursa or the formation of bony growths, called spurs, on the acromion. When the arm is raised, especially during overhead activities, the tendons and bursa get compressed or “pinched” against the acromion. This repeated friction causes irritation, swelling, and tendon inflammation, which restricts motion and generates pain in the outer shoulder or upper arm. If left unaddressed, this mechanical irritation can lead to tendon degeneration or a rotator cuff tear.
What Subacromial Decompression Involves
Subacromial decompression is most frequently performed using an arthroscopic or “keyhole” technique. This minimally invasive approach uses two or three small incisions around the shoulder, through which instruments and a tiny camera (arthroscope) are inserted. The operation is typically performed under general anesthesia, often supplemented by a regional nerve block to manage immediate post-operative discomfort.
Bursectomy
The surgeon first inserts a narrow, tube-like camera, called an arthroscope, to inspect the subacromial space and surrounding structures. The initial step is often a bursectomy, which involves removing the inflamed and thickened subacromial bursa. Removing this tissue reduces the overall volume of soft tissue in the area.
Acromioplasty
Following the bursectomy, the surgeon performs an acromioplasty, which is the core of the decompression procedure. This involves using a high-speed surgical burr to smooth the undersurface of the acromion bone. The goal is to remove bone spurs or irregularities pressing on the rotator cuff tendons, effectively widening the passageway. The procedure may also include minor repairs if additional issues, such as small rotator cuff fraying, are discovered during the exploration. Once the space is cleared and smoothed, the instruments are removed, and the small incisions are closed with sutures or surgical tape.
The Post-Surgical Recovery Timeline
Recovery begins immediately, with most patients able to go home the same day. The initial two weeks focus on pain control and protecting the surgical site using medication and ice. A sling is often provided for comfort and protection, but it is typically not worn full-time for a standalone decompression procedure. Gentle, passive movements, such as pendulum exercises, begin almost immediately to prevent stiffness.
The intermediate phase, generally spanning from two to eight weeks, centers on regaining the full range of motion. Physical therapy is important during this time, introducing active assisted range of motion exercises using a cane or pulley. Patients then progress to active motion without assistance, aiming to achieve near-normal movement of the shoulder by the end of this phase.
The advanced phase, beginning around eight to sixteen weeks, transitions the focus from mobility to strength. The patient begins strengthening the rotator cuff and scapular muscles using light resistance, often using elastic bands or very small weights. Full recovery, allowing a return to heavy physical activity or overhead sports, typically takes four to six months, though complete resolution of symptoms may take up to nine months.