How should a penetrating foot injury from stepping on a nail be managed?

Management of Penetrating Foot Injury from Stepping on a Nail

Obtain plain radiographs immediately regardless of clinical findings, as penetrating trauma is an explicit exclusion criterion for clinical decision rules like the Ottawa rules and mandates imaging to detect foreign bodies, fractures, and establish baseline bone architecture. 1, 2

Immediate Wound Assessment and Care

Initial Examination Requirements

• Ensure adequate lighting and analgesia before examination, as inadequate pain control compromises thorough assessment 3
• Measure and document wound dimensions (length, width, depth) to establish baseline 3
• Use a sterile blunt metal probe to measure wound depth and determine if there is communication with joint cavities, tendon sheaths, or bone—this is critical for detecting serious complications 3
• Pain disproportionate to injury severity near bone or joint suggests periosteal penetration and requires urgent specialist evaluation 3

Wound Cleansing and Debridement

• Cleanse with sterile normal saline only—no iodine or antibiotic-containing solutions are needed for irrigation 3
• Remove superficial debris during cleansing 3
• Debride necrotic or devitalized tissue, but do this cautiously to avoid enlarging the wound and impairing closure 3, 4
• Do not close infected wounds or wounds with suspected deep contamination 3

Neurovascular Assessment

• Check distal pulses bilaterally 3
• Test sensation and motor function distal to the wound to assess for nerve injury 3
• Weak or absent pulses require immediate surgical consultation or rapid CT angiography 3

Imaging Protocol

Plain Radiography (First-Line)

• Obtain foot radiographs immediately—penetrating trauma mandates imaging regardless of Ottawa rule criteria 1, 2
• Plain films have 98% sensitivity for radiopaque foreign bodies and detect fractures, bone disruption, and establish baseline bone architecture 2
• Do not delay imaging based on clinical decision rules, as penetrating injuries explicitly exclude their use 1, 2

Advanced Imaging When Indicated

• Order MRI if radiographs are negative but clinical suspicion for osteomyelitis remains high (especially if symptoms develop 7-14 days post-injury), as it provides superior soft tissue contrast and high sensitivity for bone marrow edema 2, 5
• Consider CT if MRI is contraindicated or if better characterization of bony destruction is needed 2
• Ultrasonography is useful for detecting retained foreign bodies, particularly rubber fragments from shoe soles 6

Tetanus Prophylaxis

Dosing Protocol

• Administer 250 units tetanus immune globulin (TIG) intramuscularly in one extremity 7
• Simultaneously give tetanus-diphtheria toxoid (Td) in a different extremity with a separate syringe 7
• For patients with uncertain or incomplete vaccination history, initiate primary series and ensure booster doses every 10 years 7
• For contaminated wounds, give booster if patient has not received tetanus toxoid within 5 years 7

Administration Precautions

• Inject TIG into deltoid or lateral thigh muscle—never use gluteal region due to sciatic nerve injury risk 7
• Aspirate before injection to confirm needle is not in a vein or artery 7
• Never administer TIG intravenously, as this can cause precipitous blood pressure drop 7

Antibiotic Management

Pathogen Considerations

• Pseudomonas aeruginosa is the most common pathogen in nail puncture wounds, especially through rubber-soled shoes 8, 5, 9
• Staphylococcus aureus is the second most common organism 8
• Diabetic patients are more likely to have polymicrobial infections 9

Treatment Algorithm

• If infection develops within 7 days: Initiate aggressive intravenous antibiotics immediately 5
• If infection develops after 7-14 days: Surgical debridement is required in addition to antibiotics 5
• Oral ciprofloxacin 750 mg twice daily for 7 days (cellulitis) or 14 days (osteochondritis) is effective after surgical intervention 8
• All treatment with ciprofloxacin requires surgical debridement, drainage, and bone exploration first 8

Surgical Intervention Criteria

Immediate Surgical Referral Required For:

• Exposed tendon or bone 3
• Signs of abscess, gas, or necrotizing fasciitis 1
• Suspected osteomyelitis with symptoms developing 7-14 days post-injury 5
• Foreign body detected on imaging 6

Surgical Approach

• Perform debridement, drainage, and bone exploration before initiating oral antibiotics 8
• In the study of 96 adult patients, 62.5% required operative intervention, with 25% having foreign body extraction 6

High-Risk Patient Considerations

Diabetic Patients

• Diabetic patients with calcaneal osteomyelitis from nail puncture wounds are more likely to have multiple pathogens and higher amputation risk 9
• Diabetic neuropathy increases risk of chronic ulceration and amputation 9
• These patients should not use Ottawa rules for imaging decisions due to diminished pain perception 10

Prognostic Factors

• Longer time from injury to hospital admission (>10 days median) correlates with treatment failure 6
• Patients receiving antibiotics in the community before hospitalization have worse outcomes 6
• Diabetes is associated with poorer treatment outcomes 6
• Fever, white blood cell count, and ESR are not reliable predictors of treatment success 6

Follow-Up Monitoring

• Warn patients about signs of infection: increasing pain, swelling, erythema, drainage, or fever 5
• Clinical presentation of osteomyelitis is often subtle with minimal systemic symptoms and few laboratory abnormalities until obvious bone infection develops 5
• Symptoms developing within 7 days require immediate aggressive IV antibiotic treatment 5
• Symptoms after 7-14 days mandate surgical intervention 5