What Is Frozen Shoulder?

What Is Frozen Shoulder?. A simple patient guide to frozen shoulder, explaining what happens inside the joint, how it progresses, and what to expect during recovery. Learn what to a

Frozen shoulder, medically known as adhesive capsulitis, is a condition where the shoulder joint becomes painful and progressively stiff.

Everyday movements such as reaching overhead, dressing, or sleeping on the affected side can feel difficult for many months.

What Happens Inside the Joint

The shoulder is a ball-and-socket joint surrounded by a thin connective tissue capsule that normally stretches to allow wide motion. In frozen shoulder, this capsule:

  • Becomes inflamed and irritated, often without an obvious triggering injury
  • Gradually thickens, with new collagen fibres laid down in a disorganised way
  • Loses its normal elasticity, particularly in the front and lower portions
  • Develops adhesions and a shortened coracohumeral ligament
  • Restricts joint movement actively (when the patient moves it) and passively (when someone else moves it)

This combination of capsular contracture and fibrosis is what separates frozen shoulder from simple stiffness after an injury.

Typical Phases

Frozen shoulder usually progresses through three overlapping phases:

  • Freezing phase (2-9 months) - increasing pain, often worse at night, with growing stiffness
  • Frozen phase (4-12 months) - pain may ease but stiffness becomes the dominant problem
  • Thawing phase (5-24 months) - gradual return of motion, sometimes incomplete

The full cycle can last from nine months to more than two years. A meaningful minority of patients are left with residual loss of motion even after the cycle ends.

Common Causes and Risk Factors

While the exact trigger is not always clear, common contributors include:

  • Prolonged immobilisation after rotator cuff injury, fracture, or surgery
  • Diabetes (risk is several times higher and the condition is often more severe)
  • Thyroid disorders, both underactive and overactive
  • Age between 40 and 60 years
  • Female sex (slightly more affected)
  • Previous shoulder problems, including subacromial impingement
  • Parkinson's disease and certain cardiovascular conditions

Common Symptoms

Patients often describe:

  • Deep, dull pain in the outer shoulder, sometimes radiating to the upper arm
  • Pain that is worst at night and disturbs sleep, especially on the affected side
  • Difficulty reaching behind the back (fastening a bra, tucking in a shirt)
  • Difficulty reaching overhead or out to the side
  • A feeling that the shoulder is "stuck" or has a hard end-point
  • Loss of both active and passive motion in multiple directions

How It Is Diagnosed

Diagnosis is usually based on:

  • A clinical examination comparing active and passive range of motion
  • A detailed history of symptom onset, diabetes, thyroid status, and previous injuries
  • Imaging such as X-ray to exclude arthritis, calcific tendinitis, or fracture
  • MRI or ultrasound to exclude rotator cuff tears when the picture is unclear
  • Sometimes blood tests for glucose, HbA1c, and thyroid function in unexplained cases

How It Is Managed

Standard management often includes:

  • Pain relief and anti-inflammatory medication during the painful phase
  • Physiotherapy focused on capsular stretching, scapular control, and gradual mobility work
  • Intra-articular corticosteroid injections, sometimes ultrasound-guided
  • Hydrodilatation (injection of fluid to gently stretch the capsule)
  • Manipulation under anaesthesia or arthroscopic capsular release for unresponsive cases
  • Sleep positioning advice and night-time pain management

Regenerative approaches such as MSC therapy are being explored as supportive options for selected patients whose symptoms have plateaued.

Key Takeaway

Frozen shoulder is a self-limiting but long-lasting condition that affects the shoulder capsule. Understanding its phases helps patients set realistic expectations and follow a structured management plan, with most regaining functional motion over time.

This article is for general informational and educational purposes only and is not a substitute for personalized medical advice. Always consult a qualified healthcare professional before considering stem cell therapy.

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