http://www.fpnotebook.com/

Human BiteAka: Clenched-fist Injury, Fight Bite

Mechanism: Hand is often injured in fist fight
1. Known as clenched-fist injury or fight bite
2. Index or Long finger MCP joint strikes tooth
  1. Site of injury obscured in extension
  2. High risk for infection spread
  3. Often associated with 5 mm Laceration over MCP
3. Associated injuries (in 75% of cases)
  1. Penetrated tendon
  2. MCP joint capsule
  3. Metacarpal head
  4. Extensor Tendon Injury
Etiologies
1. Mixed Anaerobes and aerobes
2. Staphylococcus aureus
3. Streptococcus
4. Eikenella corrodens (anaerobic Gram Negative Rod)
Signs
1. Thorough inspection
  1. Neurovascular evaluation
  2. Extensor tendon function
2. Cleansing and debridement is critical
3. Extend Laceration as needed for full visualize
Labs
1. Anaerobic and aerobic cultures from wound
2. Wound Gram Stain
Radiology: XRay affected finger
1. Fracture
2. Osteomyelitis
3. Foreign body
Management
1. Hand surgeon consultation
2. Tetanus prophylaxis
3. Wound left open, and no structures are repaired
4. Extend Puncture Wounds in distal to proximal plane
  1. Explore, irrigate, and debride wound
5. Wick placed in wound, and removed the next day
6. Apply Soft Bulky Dressing
7. Antibiotics
  1. Oral agents
    1. Amoxicillin-clavulanate (Augmentin) or
    2. Dicloxacillin with Penicillin (covers E. corrodens)
    3. Cephalexin (Keflex) with Penicillin or
    4. Clindamycin with Fluoroquinolone or
    5. Clindamycin with Trimethoprim-sulfamethoxazole
  2. Parenteral agents
    1. Indications
      1. Consider 1 parenteral dose and then oral
      2. Diabetes Mellitus
      3. Peripheral Vascular Disease
      4. Immunocompromised patient
      5. Wound older then 24 hours
      6. Signs of extensor tendon, capsule, or bone injury
      7. Systemic symptoms
      8. Concurrent Cellulitis
    2. Agents
      1. Ampicillin-sulbactam (Unasyn)
      2. Ticarcillin-clavulanate (Timentin)
      3. Cefoxitin (Mefoxin)
8. Daily Wound Cleansing and dressing changes
  1. if satisfactory healing:
    1. Antibiotics for 2-3 weeks
  2. if not improving then:
    1. Additional surgical debridement
    2. Consider IV antibiotics
  3. Complete Extensor Tendon Laceration
    1. Requires secondary repair
    2. Otherwise Secondary wound closure is not necessary
9. Inpatient Management
  1. Indicated for wound older than a few hours
References
1. Clark (2003) Am Fam Physician 68:2167
2. Presutti (1997) Postgrad Med 101(4):243

Navigation Tree

Please see the Terms and Conditions. Please also see the privacy statement regarding advertising on this page. Although access to this page is not restricted, the information found here is intended for use by medical providers. Patients should address specific medical concerns with their physicians.

This page was written by Scott Moses, MD. This page was last revised before 5/10/08, prior to consistent tracking of revision date. This page was last published on 5/10/2008. Please send comments and questions to the editor. Contact information may be found on the page About the Family Practice Notebook. These pages are best viewed with Microsoft Internet Explorer 6.0.