Suppurative Tenosynovitis

Aka: Suppurative Tenosynovitis, Infective Tenosynovitis, Pyogenic Flexor Tenosynovitis, Purulent Tenosynovitis, Kanavel's Cardinal Signs

1. See Also
   1. Hand Infection
   2. Fight Bite
2. Definition
   1. Closed space Infection within hand flexor tendon sheath
3. Pathophysiology
   1. Synovial Fluid is an ideal medium for Bacterial growth
      1. Tendon sheaths have a poor vascular supply
      2. Synovial Fluid collection
4. Causes: Organisms
   1. Most common causative organisms
      1. Staphylococcus aureus
      2. Streptococcus
   2. Other infections
      1. Gram Negative Bacteria (10% of responsible organisms)
      2. Disseminated Neisseria gonorrhoeae
      3. Disseminated candida albicans (Immunocompromised patients)
      4. Mixed oral anaerobic and aerobic Bacteria (Injection drug use)
5. Mechanisms
   1. Deep penetrating wound to the palmar surface of the hand or finger (most common)
   2. Blunt Hand Trauma
   3. Extension of felon
   4. Puncture Wound of finger
   5. High Pressure Injection Wounds
      1. Paint injection (most toxic!)
      2. Oil or grease injection
   6. Disseminated Infection (e.g. Neisseria gonorrhoeae)
6. Risk Factors
   1. Immunocompromised patients (e.g. HIV Infection)
   2. Worse outcomes with >5 years of Tobacco Abuse
      1. More serious infections, delayed Wound Healing
7. Signs
   1. Febrile and toxic appearing patient
   2. Kanavel's four cardinal signs
      1. Findings
         1. Finger is uniformly swollen (digital fusiform swelling)
         2. Finger held in slight flexion for comfort
         3. Course of inflamed sheath is markedly tender
         4. Passive finger extension causes intense pain
            1. Highly sensitive for flexor tendon infection
      2. Efficacy
         1. Test Sensitivity: 91 to 97%
         2. Test Specificity: 51 to 69%
         3. Kennedy (2017) Hand 12(6):585-90 +PMID: 28720000 [PubMed]
8. Differential Diagnosis
   1. Deep space abscess (localized tenderness)
   2. Felon
   3. Cellulitis
   4. Animal Bite
   5. Clenched-fist Injury (Fight Bite)
   6. Necrotizing Fasciitis
   7. Disseminated Candida albicans (Immunocompromised patients)
   8. Disseminated Neisseria gonorrhoeae
   9. Osteomyelitis
   10. Septic Joint
9. Diagnostics
   1. Ultrasound may show tendon effusion or abscess
10. Management
    1. Early recognition and treatment is critical
    2. Consult hand surgery urgently (within 72 hours)
    3. Hand surgery indications: No improvement in 24 hours of antibiotics
       1. Minimal incision with catheter irrigation of tendon sheath (preferred) OR
       2. Wide Incision and Drainage
          1. May be indicated in High Pressure Injection Wound
    4. Extremity elevation and Splinting
    5. Remove rings from fingers
    6. Initial parenteral antibiotics
       1. First-line parenteral coverage for MRSA
          1. Vancomycin
          2. Daptomycin
          3. Linezolid
          4. Televancin
          5. Clindamycin (depending on local sensitivities to MRSA)
       2. Injection drug use (polymicrobial coverage as well as MRSA)
          1. Vancomycin AND
          2. Piperacillin/Tazobactam (Zosyn)
       3. Disseminated Neisseria gonorrhoeae suspected
          1. Ceftriaxone (Rocephin)
       4. Older antibiotic regimens that may be considered in more mild, borderline cases (Streptococcus, Staphylococcus)
          1. Cefazolin (Ancef) or
          2. Ampicillin-sulbactam (Unasyn) or
    7. Later oral antibiotics for home
       1. Continue for 5 to 14 days after discharge
    8. Following initial surgical and antibiotics management
       1. Occupational therapy (hand therapy) Consultation
11. Complications: Acute
    1. Contiguous spread of Infection throughout hand
    2. Associated with rapid increase in pressure
       1. Pus accumulation
       2. May obliterate tendon blood supply
       3. Results in tendon necrosis, function loss, and ultimately tendon rupture
12. Complications: Chronic
    1. Chronic finger stiffness and reduced function
    2. Finger Amputation due to worsening infection
13. References
    1. Hori (2015) Crit Dec Emerg Med 29(3): 2-7
    2. Boles (1998) Hand Clin 14:567-78 [PubMed]
    3. Clark (2003) Am Fam Physician 68:2167-76 [PubMed]
    4. Mamane (2018) J Orthop 15(2): 701-6 [PubMed]
    5. Rerucha (2019) Am Fam Physician 99(4):228-36 [PubMed]