Frozen Shoulder

The shoulder joint is enclosed in a capsule, a sleeve of tissue that is normally loose and redundant, particularly at the bottom of the joint, which is what allows the arm to elevate fully. In frozen shoulder, also called adhesive capsulitis, this capsule becomes inflamed and then thickens and contracts. The redundant fold at the bottom of the joint scars down, and the ligaments at the front of the joint become thick and stiff. The result is a joint that has physically lost the tissue slack required to move. This is why frozen shoulder behaves differently from a rotator cuff problem. A patient with a rotator cuff tear cannot lift the arm themselves but the shoulder can be moved passively by someone else. A patient with frozen shoulder cannot be moved into that position by anyone, and loss of outward rotation with the arm at the side is the characteristic finding.

The condition classically progresses through overlapping phases. A freezing phase, lasting roughly two to nine months, is dominated by pain, with motion loss developing progressively and night pain that is often severe. A frozen phase, lasting roughly four to twelve months, brings less pain but marked stiffness and functional limitation. A thawing phase, lasting five months to two years or longer, brings gradual return of motion. Knowing which phase a patient is in matters, because aggressive stretching during the inflammatory phase increases pain and can prolong the course.

Frozen shoulder is often called idiopathic, meaning it arises without an identifiable cause, but several strong associations are well established.

• Diabetes: The single strongest association. Patients with diabetes have a substantially higher lifetime risk, are more likely to be affected in both shoulders, and often have a more resistant course. Any patient presenting with frozen shoulder and no known diagnosis warrants screening.
• Thyroid disease: Both underactive and overactive thyroid conditions are associated.
• Age and sex: Most common between the ages of forty and sixty, and more common in women.
• Immobilization: A period in a sling after injury or surgery, or after a fracture anywhere in the arm.
• Prior shoulder surgery or injury: Stiffness following an operation or trauma, sometimes described as secondary or post-surgical stiffness.
• Other medical conditions: Cardiovascular disease, Parkinson disease, and Dupuytren contracture are each associated.
• Prior frozen shoulder: Involvement of the opposite shoulder occurs in a meaningful proportion of patients, though recurrence in the same shoulder is uncommon.

• Progressive loss of motion: Increasing difficulty reaching overhead, behind the back, and across the body, developing over weeks to months.
• Loss of outward rotation: Difficulty rotating the arm outward with the elbow at the side, the most characteristic finding and the one that distinguishes it from cuff disease.
• Severe night pain: Often the most distressing symptom, frequently disrupting sleep for months during the early phase.
• Sharp pain at the end of motion: A sudden catching pain when the arm reaches the limit of its range.
• Difficulty with everyday tasks: Fastening a bra, reaching a back pocket, putting on a coat, washing hair, reaching a seatbelt.
• A shoulder that feels stuck: Patients often describe the sensation as a hard stop rather than weakness or pain limiting the motion.

Frozen shoulder is a clinical diagnosis. Dr. Rynecki Baker takes a detailed history covering the onset and progression of stiffness, sleep disturbance, prior injury or surgery, and medical conditions including diabetes and thyroid disease. The decisive part of the examination is comparing active and passive motion: when the patient cannot move the arm and the examiner cannot either, particularly in outward rotation, the diagnosis is established. She also examines the rotator cuff and the neck, as frozen shoulder is frequently confused with cuff tearing, arthritis, and cervical spine pathology, and can coexist with them.

X-rays are typically normal in frozen shoulder, and obtained principally to exclude arthritis, a missed dislocation, or a fracture, all of which can also produce a stiff shoulder. MRI is not required to make the diagnosis and is often ordered unnecessarily. It is useful when a rotator cuff tear is suspected alongside the stiffness, or when the presentation is atypical. Findings can include thickening of the capsule and the ligaments at the front of the joint. Screening for diabetes and thyroid dysfunction is appropriate in patients with concerning symptoms without a known diagnosis, as frozen shoulder is sometimes the first presentation of undiagnosed diabetes.

Frozen shoulder is commonly mistaken for a rotator cuff problem, and the consequences of that error are real. Patients spend months in a therapy program aimed at strengthening a shoulder that will not move, undergo an MRI that finds incidental cuff changes, and in some cases have an operation for a cuff tear that was never the problem, emerging with a stiffer shoulder than they started with. Operating on an inflamed, frozen shoulder is one of the more reliable ways to make it worse.

Dr. Rynecki Baker’s training at NYU Langone Health and Hospital for Special Surgery and her dedicated focus on shoulder surgery and sports medicine mean patients are evaluated by a specialist who makes the diagnosis on examination rather than on imaging, and who matches treatment to the phase of the condition. The biology of stiffness and scar tissue is also an area of her research interest: she is a co-investigator on a national randomized controlled trial, funded by the Arthroscopy Association of North America, testing whether a common blood pressure medication can prevent the stiffness and scar tissue that sometimes follow ligament reconstruction.

She is also realistic with patients about the timeline, which is one of the hardest parts of this condition.