Adhesive capsulitis (frozen shoulder) is a painful inflammatory process in the shoulder that causes decreased range of motion. Often, there is no known cause or event leading to the development of this condition. Most frequently, the condition is caused by a relatively benign activity such as reaching in the back seat of a car. Patients may also get a frozen shoulder after a surgery as a result of scarring.
The capsule is a tissue layer attached to each side of a joint. The lining of the capsule is called synovium, which is what makes the fluid that lubricates the joint. When patients have adhesive capsulitis, the capsule becomes inflamed, which is what causes pain. In adhesive capsulitis the capsule also becomes thick, which causes it to contract and leads to the decreased range of motion.
Frozen shoulders are most commonly treated without surgery. Conservative treatments include physical therapy with a daily home exercise program, pain medication, and steroid injections. When patients fail to progress with conservative treatments and have pain/limited range of motion that significantly interferes with their quality of life, surgery can be considered. This involves a manipulation under anesthesia and a scope with lysis of adhesions.
- Shoulder pain
- Decreased range of motion, particularly with rotating the arm with the arm out to the side
- Shoulder weakness from pain
- Physical Therapy - A formal course of physical therapy (PT) is the first line of treatment. It is very important that this be coupled with a gentle daily stretching home exercise program. PT can help patients regain the strength and range of motion and will keep track of the progress (or lack thereof). It is important not to overstretch the shoulder while doing the exercises as this can sometimes cause more inflammation.
- Injections - Steroid injections into the shoulder joint (intra-articular) can be very effective at alleviating pain, which can make it easier to participate in physical therapy. Intra-articular steroids can also stop the inflammatory process of frozen shoulder, preventing further scar tissue from forming. Steroid injections into the subacromial space above the rotator cuff can also be effective, but these are not used as frequently as steroid injections into the shoulder joint.
- Anti-inflammatories - Nonsteroidal anti-inflammatory medications such as Ibuprofen or Aleve can help decrease inflammation and pain caused by a frozen shoulder. This can be beneficial in addition to physical therapy, so patients can have less pain while regaining their motion and strength. Prescription-strength anti-inflammatory medications are occasionally prescribed if over-the-counter medications are not working.
- Surgery - When patients fail to progress or respond to conservative treatments, surgery is recommended.
Frozen shoulder often starts after a trivial shoulder injury such as straining the shoulder after reaching back. The pain progressively gets worse and then leads to significant shoulder stiffness. Typically shoulder strength is preserved, although the shoulder may feel weak because of pain. In clinic, radiographs appear normal. If weakness is noted on a physical exam, an MRI is ordered to ensure there are no other abnormalities to the shoulder. An MRI evaluates soft tissue structures such as the rotator cuff tendons and can also reveal thickening/scarring of the capsule, which is what tightens in cases of frozen shoulder.
Surgery is reserved for patients who fail to progress with conservative treatment such as gentle stretching, anti-inflammatory pain medication, and steroid injections. The patient’s age and the patient’s level of function/demand will determine whether conservative or surgical treatment is best.
The risks include persistent stiffness and weakness from lack of use of the affected arm. Frozen shoulder can resolve on its own, but studies have shown that it can take up to two years. Guided physical therapy and steroid injections can shorten this time course substantially. Patients typically regain 80-85% of their shoulder function with time.