What is the treatment for a plant thorn injury?

Treatment of Plant Thorn Injuries

Plant thorn injuries require immediate thorough wound irrigation, removal of any retained foreign body material, and consideration of antibiotic prophylaxis for deep wounds or high-risk locations, with tetanus prophylaxis if vaccination status is not current.

Initial Wound Management

Wound Cleansing and Irrigation

• Irrigate the wound thoroughly with copious amounts of sterile saline or potable water to remove foreign bodies and contaminants 1
• Avoid high-pressure irrigation as this may drive bacteria and plant material deeper into tissue layers 2
• Remove superficial debris carefully without causing additional tissue damage 2
• Deep debridement should be performed cautiously to avoid enlarging the wound 2

Foreign Body Detection and Removal

• Retained plant material is the primary cause of complications including chronic synovitis, tenosynovitis, and septic arthritis 3, 4, 5, 6, 7
• High-resolution ultrasonography is the preferred imaging modality for detecting retained thorns, as it can identify foreign bodies smaller than 0.5 mm and is inexpensive, non-radioactive, and readily accessible 4
• Immediate surgical removal of retained thorn material results in complete cure, while delayed diagnosis leads to significant morbidity 3
• If a foreign body is suspected near a joint or bone (indicated by pain disproportionate to injury severity), imaging and surgical exploration are warranted 2, 4

Antibiotic Considerations

Risk Stratification for Antibiotic Prophylaxis

While universal antibiotic prophylaxis is not recommended for all penetrating injuries 2, consider 3-5 days of prophylactic antibiotics for:

• Deep wounds 2
• Wounds in critical locations: hands, feet, areas near joints, face, genitals 2
• Patients at elevated infection risk (immunocompromised, diabetes, peripheral vascular disease) 2
• Patients with implants (artificial heart valves, joint prostheses) 2

Antibiotic Selection

• First-line: Amoxicillin-clavulanate for broad-spectrum coverage 2
• Alternative oral agents: Doxycycline, or penicillin VK plus dicloxacillin 2
• For soil-contaminated wounds with tissue damage, add penicillin coverage for anaerobes including Clostridium species 2
• Avoid first-generation cephalosporins (cephalexin), penicillinase-resistant penicillins (dicloxacillin), macrolides, and clindamycin alone as these have inadequate coverage for potential pathogens 2

Important Microbiologic Consideration

• Contrary to traditional teaching, thorn injuries should not be presumed sterile 6
• Pantoea agglomerans (a gram-negative enteric pathogen) is the most commonly isolated organism when bacterial growth occurs 6
• If infection develops, empiric coverage should include gram-negative enteric pathogens until culture results are available 6

Wound Closure and Dressing

• Do not close infected wounds 2
• For fresh, clean wounds presenting within 8 hours, wound margin approximation with Steri-Strips followed by delayed primary or secondary closure is prudent 2
• Cover the wound with antibiotic ointment (if no allergies) and a clean occlusive dressing to maintain moisture and prevent contamination 1
• Facial wounds may be an exception and can be closed primarily by a plastic surgeon after meticulous wound care and prophylactic antibiotics 2

Tetanus Prophylaxis

• Administer tetanus toxoid if vaccination is not current (last dose >5 years for contaminated wounds, >10 years for clean wounds) or vaccination status is unknown 1

Adjunctive Measures

• Elevate the injured extremity during the first few days to reduce swelling and accelerate healing 2, 1
• For hand injuries, use a sling for outpatients 2

Follow-up and Monitoring

• Follow up within 24 hours either by phone or office visit 2
• Monitor for signs of infection: progressive erythema, increasing pain, warmth, purulent drainage, foul odor, fever, or increasing swelling 1
• If infection progresses despite appropriate antimicrobial and supportive therapy, hospitalization should be considered 2

Critical Pitfalls to Avoid

• Do not dismiss the possibility of retained foreign material, even if not visible on initial examination - this is the most common cause of delayed complications 3, 4, 5, 6, 7
• Do not assume sterility - bacterial infection, particularly with Pantoea agglomerans, can occur 6
• Do not delay treatment - immediate diagnosis and intervention prevent chronic synovitis, tenosynovitis, and septic arthritis 3, 4, 5, 6, 7
• Pain near a joint or bone should raise suspicion for deeper penetration requiring imaging and possible surgical exploration 2, 4

Surgical Intervention

If synovitis or tenosynovitis develops, arthroscopic or open synovectomy with foreign body removal is the only curative treatment 4, 5, 6, 7

• Begin empiric antibiotics with gram-negative coverage until culture results return 6
• Complete synovectomy may be necessary for full resolution 6, 7