Calcifying Tendinopathy of the shoulder isn't the most common presentation, and I think might be better presented initially as a case which might make your day 1 management easier before we get into the pathophysiology.
Case Presentation: Calcifying Tendinopathy of the Shoulder¶
Typical Patient History¶
Patient Demographics: The patient is typically a middle-aged adult, most frequently presenting between the ages of 30 and 60 years. Rotator cuff calcific tendinopathy occurs a little bit more commonly in women (in about 70% of cases). The condition is generally not correlated with physical activity. In approximately 10--20% of patients, the calcific deposits are bilateral. Associated conditions may include diabetes and thyroid disorders.
Clinical Presentation
The clinical features vary depending on the stage of the disease.
• Most Common Location: The condition usually affects the supraspinatus tendon in the rotator cuff (about 80% of cases). The calcification is often found in the "critical zone," located 1.5--2 cm away from the tendon\'s insertion on the greater tuberosity.
Knowledge Check
The supraspinatus tendon is affected in about 80% of calcific tendinopathy cases, typically in the "critical zone" located 1.5-2 cm from the greater tuberosity insertion.
• Symptom Onset (Acute Presentation):
If the patient seeks acute care, they are typically in the resorptive phase of the calcific stage. This phase is classically characterized by severe acute pain that occurs suddenly and is highly disabling. The pain is often resistant to common analgesics and tends to increase at night. Patients may seek emergency medical consultation due to the sudden onset of symptoms.
• Symptom Onset (Chronic Presentation):
If the patient is in the formative or resting stages, they may be asymptomatic in 20% of cases. If symptoms are present, they are often characterized by low-grade or chronic intermittent pain. This chronic pain may occur during shoulder forward flexion.
Typical Physical Examination Findings¶
Physical examination findings depend heavily on the severity of the inflammatory reaction, particularly if the patient is in the painful resorptive phase:
• Inspection and Palpation:
Local signs of inflammation may be present, including local heat, redness, swelling, and oppressive pain. Tenderness is common upon palpation of the greater tuberosity, deltoid, bicipital groove, acromial process, and coracoid process.
• Range of Motion (ROM):
Patients usually present with restriction of range of movements (ROM). All glenohumeral movements, including forward flexion, abduction, and rotation, may be painful and limited. Patients may instinctively maintain a posture of internal rotation to relieve pain.
• Impingement Signs:
Findings typical of subacromial impingement may be present. A painful arc (pain during the midrange of abduction, typically between 70 and 120 degrees) is often observed. Positive Hawkins-Kennedy test and pain on forced shoulder flexion to end range may be present.
• Specific Tests (If Supraspinatus is Involved):
Tests stressing the affected tendon, such as the long lever shoulder abduction (internal or external rotation, abduction, or flexion, doesn't really make a huge difference, if pain is tolerable), may provoke pain. Active range of motion should be intact, albeit painful, distinguishing it from a complete tendon tear. Severe motion limitations and associated swelling may necessitate differentiation from acute conditions like septic arthritis.
What should you be doing on Day 1?¶
First Assessment Priorities¶
- Stage Identification:
Use clinical history (acute, severe pain suggests the resorptive phase; chronic low-grade pain suggests the formative/resting phase) to estimate the underlying pathological stage, which guides prognosis and intervention strategy.
- Imaging Review:
Confirm the presence, location, size, and morphology of the calcific deposits using imaging studies like conventional radiography (CR) or ultrasound (US), which are the preferred diagnostic methods.
- ROM Assessment:
Assess both passive and active range of motion to determine the degree of restriction. This is crucial to identify or rule out secondary joint stiffness, such as adhesive capsulitis (frozen shoulder), which can occur as a complication of chronic pain.
- Conservative Failure Check:
If the condition is chronic, ascertain if the patient has had prior symptoms persisting for at least six months, including three months of standardized nonoperative treatment (a definition of failed conservative treatment).
Answering Patient Questions¶
"What's wrong with me?"
What is wrong is that you have a condition called "Calcific Tendinopathy of the Rotator Cuff". This is a very common condition characterized by the deposition of calcium hydroxyapatite crystals within the shoulder tendons, primarily the supraspinatus tendon.
Calcifying tendinopathy of the rotator cuff is thought to be a cell-mediated disease. The tendon tissue undergoes a change (metaplasia) that allows the calcium to deposit, but no-one is really sure why this happens.
The reason your pain is so severe right now is likely because you are in the resorptive phase. In this phase, your body recognizes the calcium deposits as foreign and initiates a strong inflammatory reaction to break them down and absorb them. This process causes swelling and increased pressure inside the tendon, leading to intense, debilitating pain.
"What's going to happen?"¶
The good news is that calcifying tendinopathy of the rotator cuff is usually a self-limiting disorder. This means that in the majority of cases, the condition tends to resolve spontaneously over time. The natural course of the disease includes the eventual reabsorption of the calcium deposits by the body.
Knowledge Check
Calcifying tendinopathy is usually a self-limiting disorder that tends to resolve spontaneously over time, with eventual reabsorption of calcium deposits by the body. This is why conservative management is the primary treatment approach.
When the calcification resolves completely, the involved tendon undergoes complete healing or remodeling ("restitutio ad integrum"). This entire process can take several months. While spontaneous resolution occurs in many cases, if symptoms persist, active intervention may be needed.
"What can be done?"¶
The primary treatment is conservative and focuses on symptom management, especially because the condition often resolves naturally.
1. Pain Management (Immediate):¶
◦ Rest: Relative rest and potentially using an arm sling temporarily to reduce acute strain are recommended.
◦ Medication: Oral Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are commonly used to relieve pain and reduce the intense inflammation associated with the resorptive phase.
2. Rehab:¶
◦ Once the acute pain is managed (often within 1--2 weeks), we will begin physical therapy. The immediate goal is to prevent the shoulder joint from becoming stiff (frozen shoulder).
◦ We will start with exercises focused on maintaining range of motion (ROM), such as passive exercises and pendulum exercises.
◦ Later, once pain is comfortable, we will introduce strengthening exercises to optimize joint mechanics.
3. Minimally Invasive Options (If Symptoms are Severe or Persistent): If your pain remains severe, or if the conservative approach fails to provide relief after 3--6 months, we may consider highly effective minimally invasive options:
◦ Ultrasound-Guided Needling (UGPL/Barbotage): This procedure, which is safe and effective, uses a needle under ultrasound guidance to wash out and aspirate the calcium deposits. This procedure is generally indicated in the acute phase, especially if the calcification is soft or fluid-like.
◦ Extracorporeal Shock Wave Therapy (ESWT): This involves applying repetitive pulses over the affected shoulder to break up the deposits and promote resorption. High-energy focused ESWT (H-FSW) is considered effective for pain relief and deposit resolution.
4. Surgery (Last Resort): Surgery remains the most invasive option and is reserved for chronic cases that fail to improve after other approaches, typically lasting more than six months.
The priority now is managing your acute pain and starting conservative therapy, as most patients respond favourably to conservative treatment. This is often highly effective due to the condition\'s natural tendency toward spontaneous resolution
Pathophysiology¶
OK, read on if you genuinely are interested in this, knowing full well that you aren't going to be seeing many of these patients in a typical sports setting -- this is far more likely to be one of the support staff for a club/team, or a former player still involved.
The pathophysiology of rotator cuff calcific tendinopathy is complex, controversial, and characterized as a dynamic pathological process involving the deposition and eventual spontaneous reabsorption of calcium crystals within the rotator cuff tendons.
1. Aetiology and Mechanism of Calcification¶
While the precise cause of calcifying tendinopathy of the rotator cuff remains unclear, the most accepted model views it as a cell-mediated disease rather than a simple degenerative process.
A. Reactive Calcification Theory (Dominant) The prevalent theory, popularized by Uhthoff and Loehr, describes calcifying tendinopathy of the rotator cuff as a series of processes occurring in otherwise-healthy tendons.
1. Metaplastic Transformation: *The process is initiated by a metabolic disorder or low oxygen tension (**hypoxia*) inside the tendon. This leads to the transformation, or fibrocartilaginous metaplasia, of native tendon cells (tenocytes) into chondrocyte-like cells.
2. Mineralization: These chondrocyte-like cells express key enzymes, such as tissue non-specific alkaline phosphatase (TNAP) and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Because pyrophosphate inhibits mineralization, the action of these enzymes promotes the formation of calcium hydroxyapatite crystals within the tendon matrix. The deposits are usually characterized as a focal collation of these crystals embedded between grossly healthy collagen fibers.
3. Self-Resolution: This cell-mediated process explains why calcifying tendinopathy of the rotator cuff is typically a self-limiting disorder that leads to spontaneous resorption of the deposits and eventual complete healing (restitutio ad integrum).
B. Degenerative Calcification (Competing Theory) The older degenerative hypothesis, proposed by Codman, suggested that repetitive microtrauma, aging, and decreased blood supply lead to tissue degeneration, necrosis, and eventual calcification. This theory is generally dismissed as it fails to explain the disease's characteristic peak age incidence (30--60 years) or its self-limiting nature.
2. Pathological Stages of calcifying tendinopathy of the rotator cuff (Uhthoff Cycle)¶
The development of calcifying tendinopathy of the rotator cuff follows a distinct progression, primarily comprising three stages:
I. Pre-calcific Stage¶
This is the preconditioning phase.
• Pathology: The area of future calcification undergoes fibrocartilaginous metaplasia as tenocytes transform into chondrocytes.
• Clinical Relevance: This phase is considered "silent" or rarely symptomatic due to the absence of calcification or inflammation.
II. Calcific Stage¶
This stage is subdivided into three phases:
1. Formative Phase:¶
◦ Pathology: Active calcium hydroxyapatite crystals are formed and begin to coalesce into large foci.
◦ Appearance: The deposit is dense, homogeneous, and typically has a chalk-like appearance.
◦ Clinical Relevance: Patients are often asymptomatic or experience mild, subacute, or chronic intermittent pain.
2. Resting Phase:¶
◦ Pathology: Calcium deposition ceases. The calcifications are stable and mature, typically presenting as a hard, arc-shaped plaque.
◦ Clinical Relevance: Symptoms are usually mechanical pain caused by the hard mass impinging on surrounding structures, sometimes resulting in clicking or snapping sensations during movement.
3. Resorptive Phase:¶
◦ Pathology: This is characterized by an aggressive inflammatory reaction as the body attempts to resolve the condition.
◦ Cellular Mechanism: Macrophages and multi-nuclear giant cells infiltrate the area through thin-walled vascular channels to phagocytose (absorb) the deposits.
◦ Appearance: The deposit liquefies and becomes soft, creamy, or toothpaste-like.
◦ Clinical Relevance: This stage causes severe acute, disabling pain due to edema, extravasation of calcium crystals into the subacromial bursa (SASD), and resulting increased intratendinous pressure.
Knowledge Check
The resorptive phase causes severe acute, disabling pain as the body mounts an aggressive inflammatory response to break down and absorb the calcium deposits through macrophages and giant cells, creating increased intratendinous pressure.
III. Postcalcific Stage¶
• Pathology: The tendon tissue undergoes remodeling by fibroblasts. The space previously occupied by the calcium is replaced by granulation tissue, then Type III collagen, and finally Type I collagen, leading to the restoration of tendon architecture and complete healing.
• Clinical Relevance: This phase is typically associated with symptom resolution.
3. Mechanisms of Pain and Migration¶
Pain in calcific tendinopathy is multifactorial, particularly during the unstable resorptive phase.
A. Causes of Pain The mechanisms producing shoulder pain include:
1. Chemical Irritation: Caused by the calcium deposits or the resulting inflammatory response.
2. Increased Local Pressure: Due to swelling within the tight tendon tissue, often leading to the formation of "chemical furuncles".
3. Impingement: Resulting from bursal thickening or irritation by prominent calcific deposits, causing collision in the subacromial space.
4. Chronic Stiffness: Pain caused by chronic stiffness of the glenohumeral joint, often resembling secondary adhesive capsulitis (frozen shoulder).
B. Migration of Calcific Deposits During the resorption process, particularly when the deposits are soft and unstable, the hydroxyapatite calcium crystals may migrate from the rotator cuff tendons to adjacent tissues, often due to mechanical forces.
• Intrabursal Migration: This is the most common pattern, where calcium is extruded towards the sub-bursal space and subacromial bursa, leading to acute microcrystalline bursitis and severe inflammatory pain.
• Intraosseous Migration: Calcium may migrate caudally into the bone, causing erosion or osteolysis of the greater tuberosity.
• Intramuscular Migration: Migration into adjacent muscle belly is an unusual evolution of calcifying tendinopathy of the rotator cuff.
C. Link to Adhesive Capsulitis The pathology of calcifying tendinopathy of the rotator cuff is linked to shoulder arthrofibrosis (Adhesive Capsulitis, AC). Chronic micro-leakage of calcium from the tendon fibers into the synovial recesses of the glenohumeral joint may be a contributing factor, initiating synovial inflammation and thickening, a condition known as chemical synovitis, potentially leading to AC. Additionally, prolonged pain-induced hypomobility associated with CT can contribute to the development of secondary adhesive capsulitis