What is tenosynovitis?

Tenosynovitis: Definition, Diagnosis, and Management

Tenosynovitis is inflammation of a tendon and its surrounding synovial sheath, which can present as either exudative (inflammatory) or stenosing (restrictive) forms, causing pain, swelling, and limited function of the affected area. 1

Pathophysiology and Classification

Tenosynovitis occurs when the synovial lining of the tendon sheath becomes inflamed, leading to:

• Excess fluid production within the sheath
• Thickening of the tendon sheath
• Restricted tendon movement
• Pain and functional limitation

Two main types exist:

1. Exudative tenosynovitis: Characterized by fluid accumulation and inflammation
2. Stenosing tenosynovitis: Characterized by thickening of the retinaculum or pulley that constricts the osseofibrous tunnel through which the tendon runs 2

Etiology

Tenosynovitis can result from various causes:

• Mechanical factors: Repetitive movements, overuse, or trauma
• Inflammatory conditions:
  • Rheumatoid arthritis
  • Psoriatic arthritis 3
  • Seronegative spondyloarthropathies 4
• Infectious causes: Bacterial (including syphilis) 5
• Metabolic conditions: Diabetes is a risk factor and associated with poor prognosis 6
• Anatomical factors: Local anatomy can predispose to stenosing forms

Common Presentations

Tenosynovitis can affect various anatomical locations:

• Upper extremities:

  • De Quervain's tenosynovitis (first dorsal compartment of the wrist)
  • Trigger finger (flexor digitorum tendons)
  • Extensor carpi ulnaris, extensor carpi radialis tenosynovitis

• Lower extremities:

  • Posterior tibial tendon tenosynovitis
  • Flexor hallucis tenosynovitis
  • Peroneal tendon tenosynovitis

Clinical Features

• Pain along the tendon course
• Swelling over the affected area
• Crepitus with movement
• Limited range of motion
• Tenderness to palpation
• In stenosing forms: catching, locking, or triggering of digits

Diagnostic Approach

Imaging

• Ultrasound: First-line imaging modality

  • Highly effective for detecting tenosynovitis with a detection rate 2.48-4.69 times better than clinical examination 3, 1
  • Can identify synovial thickening, fluid in tendon sheath, and increased vascularity
  • Allows dynamic assessment of tendon movement

• MRI:

  • Superior for detecting tenosynovitis compared to clinical examination 3
  • Particularly sensitive for detecting extracapsular inflammation 3
  • MRI studies have identified tenosynovitis as both the most prevalent abnormality and the strongest risk factor for arthritis development in at-risk individuals 3

Laboratory Tests

For suspected inflammatory or infectious causes:

• ESR and CRP (may be elevated)
• Rheumatoid factor, anti-CCP antibodies
• Analysis of synovial fluid when possible
• Appropriate tests for suspected infectious causes

Management

Conservative Treatment

1. Rest and Activity Modification:

   • Avoiding repetitive movements that aggravate symptoms
   • Relative rest of the affected area 1

2. Medications:

   • NSAIDs for short-term pain relief (1-2 weeks)
   • Topical NSAIDs may have fewer systemic side effects 1

3. Physical Interventions:

   • Splinting (particularly thumb spica splinting for De Quervain's)
   • Cryotherapy (ice application for 10-minute periods)
   • Physical or occupational therapy with eccentric strengthening and tendon gliding exercises 1

Interventional Treatments

• Corticosteroid Injections:

  • Effective for symptom relief in many cases
  • Intra-articular glucocorticoid injections are conditionally recommended for initial therapy 1
  • Should be performed with ultrasound guidance when possible

• Disease-Modifying Antirheumatic Drugs (DMARDs):

  • For tenosynovitis associated with inflammatory arthritis
  • Conventional synthetic DMARDs are strongly recommended for inadequate response to NSAIDs/steroid injections
  • Methotrexate is conditionally recommended as the preferred agent 1

• Biologic DMARDs:

  • Conditionally recommended for inadequate response to conventional DMARDs
  • No preferred biologic DMARD has been identified 1

Surgical Management

• Indicated when conservative measures fail (typically after 4-6 months)
• Procedures include:
  • Synovial debridement
  • Release of constricting pulley or retinaculum
  • Repair of any longitudinal split tears 4
  • Surgical synovial débridement should be performed early (6 weeks) in patients with enthesopathies 4

Prognostic Considerations

• Tenosynovitis detected on imaging is a significant predictor of disease progression in inflammatory arthritis
• MRI-detected tenosynovitis is strongly associated with arthritis development (HR 8.39) 3
• Early detection and treatment are crucial to prevent long-term complications
• Baseline tenosynovitis on ultrasound appears to be predictive of erosive progression at 1 year (OR 7.18) and 3 years (OR 3.4) 3

Special Considerations

• For infectious tenosynovitis, appropriate antimicrobial therapy is essential
• In cases associated with systemic conditions, treatment of the underlying disorder is crucial
• Regular monitoring with ultrasound can help assess treatment response and disease progression

Tenosynovitis represents an important clinical entity that requires prompt diagnosis and appropriate management to prevent long-term complications and preserve function.