Bursitis

Bursitis is a common musculoskeletal condition characterized by inflammation of the bursae, small fluid-filled sacs that cushion the bones, tendons, and muscles around joints. It can cause pain, swelling, and restricted movement, affecting daily activities and quality of life. Understanding its anatomy, function, and pathophysiology is essential for effective management.

Anatomy and Function of Bursae

Structure of Bursae

Bursae are small, sac-like structures lined by a synovial membrane and filled with a thin layer of synovial fluid. They are strategically located in areas where friction occurs between bone, tendons, muscles, and skin.

• Definition and Types: Bursae can be categorized as synovial bursae, which are naturally occurring and contain synovial fluid, and adventitial bursae, which develop in response to repeated friction or pressure.
• Locations: Major bursae are found in the shoulder, elbow, hip, knee, and heel, with each site having specific clinical relevance.

Physiological Role

The primary function of bursae is to facilitate smooth movement and reduce friction between musculoskeletal structures.

• They allow tendons to glide smoothly over bones during joint movement.
• Bursae absorb mechanical stress and protect tissues from repetitive trauma.
• They help maintain joint integrity by minimizing wear and tear on surrounding structures.

Pathophysiology of Bursitis

Mechanisms of Inflammation

Bursitis develops when the bursa becomes irritated, leading to inflammation and accumulation of excess fluid. The causes can be mechanical, infectious, or systemic.

• Overuse and Repetitive Trauma: Activities involving repetitive motion or prolonged pressure on a joint can lead to mechanical irritation of the bursa.
• Infectious Causes: Septic bursitis occurs when bacteria, commonly Staphylococcus aureus, infect the bursa, causing redness, warmth, and swelling.
• Systemic Inflammatory Conditions: Conditions such as rheumatoid arthritis, gout, and spondyloarthropathies can trigger inflammatory changes in bursae.

Classification

• Acute vs Chronic Bursitis: Acute bursitis is short-term, often caused by sudden injury or infection, whereas chronic bursitis results from prolonged irritation or repetitive trauma.
• Septic vs Aseptic Bursitis: Septic bursitis involves bacterial infection, requiring prompt antibiotic treatment, while aseptic bursitis arises from non-infectious causes such as overuse or systemic inflammation.

Etiology and Risk Factors

Bursitis can arise from a variety of causes, often influenced by lifestyle, occupation, and underlying health conditions. Identifying risk factors is essential for prevention and targeted management.

• Occupational and Sports-Related Overuse: Repetitive movements such as throwing, kneeling, or lifting heavy objects increase stress on bursae, particularly in the shoulder, elbow, and knee.
• Age-Related Degenerative Changes: Aging leads to decreased elasticity and resilience of tendons and bursae, making them more susceptible to inflammation.
• Underlying Medical Conditions: Conditions such as diabetes, obesity, and metabolic disorders can predispose individuals to bursitis by impairing tissue healing and increasing mechanical stress.
• Trauma or Direct Injury: Acute trauma, such as a fall or blow to a joint, can directly irritate the bursa and trigger inflammatory responses.

Clinical Presentation

Signs and Symptoms

Bursitis typically presents with localized symptoms that vary depending on the affected site and severity of inflammation.

• Pain: Often worsens with movement or pressure over the affected joint and may be sharp or aching.
• Swelling and Tenderness: The bursa may become visibly swollen, soft, and tender to touch.
• Reduced Range of Motion: Pain and inflammation can limit joint mobility and functional use of the limb.
• Redness and Warmth: Common in septic bursitis or acute inflammatory episodes.

Commonly Affected Sites

Bursitis can occur in any bursa, but certain locations are more frequently involved due to mechanical stress or overuse.

• Shoulder (Subacromial Bursitis): Pain during overhead movements or lifting objects.
• Elbow (Olecranon Bursitis): Swelling at the tip of the elbow, often due to leaning or trauma.
• Hip (Trochanteric Bursitis): Lateral hip pain, worsened by walking, climbing stairs, or lying on the affected side.
• Knee (Prepatellar and Infrapatellar Bursitis): Swelling in front of the kneecap, common in occupations requiring kneeling.
• Other Less Common Sites: Achilles, wrist, and ankle bursae can also be affected depending on activity or injury.

Diagnostic Evaluation

Clinical Examination

Diagnosis of bursitis begins with a thorough clinical evaluation focusing on symptoms, joint function, and physical findings.

• Inspection: Observing for swelling, redness, or deformity over the affected joint.
• Palpation: Identifying tenderness, warmth, and localized fluid accumulation.
• Range-of-Motion Testing: Assessing limitations and pain during active and passive joint movements.
• Special Maneuvers: Site-specific tests to provoke symptoms and distinguish bursitis from tendon or joint pathology.

Imaging Studies

Imaging helps confirm the diagnosis, evaluate the extent of inflammation, and rule out other conditions.

• Ultrasound: Detects fluid accumulation, bursa thickening, and guide for aspiration or injections.
• MRI: Provides detailed visualization of soft tissues, useful in chronic or complex cases.
• X-ray: Primarily to exclude fractures, bone spurs, or degenerative joint disease.

Laboratory Tests

Laboratory evaluation is indicated especially in suspected infectious or systemic causes of bursitis.

• Blood Tests: Complete blood count, inflammatory markers (ESR, CRP), and uric acid levels.
• Aspiration and Synovial Fluid Analysis: Confirms infection, identifies crystals, and guides antibiotic therapy if needed.

Management and Treatment

Conservative Management

Most cases of bursitis respond to non-invasive treatment aimed at reducing inflammation and restoring joint function.

• Rest and Activity Modification: Avoiding activities that exacerbate symptoms.
• Physical Therapy: Stretching and strengthening exercises to support joint stability and reduce recurrence.
• NSAIDs and Analgesics: Medications to relieve pain and inflammation.
• Ice or Heat Therapy: Ice reduces acute inflammation, while heat can alleviate chronic stiffness.

Interventional Treatments

For persistent or severe bursitis, targeted interventions can provide faster relief.

• Corticosteroid Injections: Directly reduce inflammation within the bursa.
• Platelet-Rich Plasma (PRP) Therapy: Emerging treatment aimed at enhancing tissue healing and reducing inflammation.

Surgical Management

Surgery is reserved for cases unresponsive to conservative and interventional therapies or complicated by infection.

• Bursa Excision (Bursectomy): Removal of the inflamed bursa to relieve chronic pain.
• Indications: Recurrent bursitis, persistent pain, or septic bursitis not responding to antibiotics.

Complications

Although bursitis is generally manageable, untreated or severe cases can lead to complications that affect joint function and overall health.

• Chronic Pain and Disability: Persistent inflammation can result in long-term discomfort and limitation of joint movement, affecting daily activities.
• Septic Spread of Infection: In cases of septic bursitis, infection can extend to surrounding tissues or bloodstream, posing serious health risks.
• Recurrence: Repeated irritation or inadequate treatment may lead to recurrent episodes of bursitis at the same site.
• Joint Stiffness: Prolonged inflammation can cause fibrosis of the bursa or surrounding structures, restricting mobility.

Prevention

Preventing bursitis focuses on reducing mechanical stress on joints, maintaining muscle strength, and early management of injuries.

• Ergonomic and Activity Modifications: Adjusting workstations, using protective pads, and avoiding repetitive joint strain.
• Strengthening and Flexibility Exercises: Regular exercise to enhance muscle support around joints and maintain range of motion.
• Prompt Treatment of Minor Injuries: Early care of trauma, sprains, or overuse injuries can prevent progression to bursitis.
• Weight Management: Maintaining healthy body weight to reduce mechanical stress on weight-bearing joints.

Prognosis

The prognosis of bursitis is generally favorable, especially when identified early and managed appropriately. Most patients experience significant symptom relief with conservative measures.

• Expected Recovery Timeline: Acute bursitis often resolves within a few weeks, while chronic cases may require several months of treatment.
• Factors Influencing Prognosis: Early intervention, adherence to therapy, absence of infection, and management of underlying medical conditions improve outcomes.
• Recurrence Risk: Without preventive measures, repetitive stress or overuse may lead to recurrence.

References

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