Inside Insights On Treating Puncture Wounds
Treating puncture wounds in the lower extremity can be challenging, especially given the potential for retained foreign bodies. In the first part of a discussion, our expert panelists discuss appropriate workup and diagnostic studies for such wounds, offer their perspectives on imaging modalities, and impart a few helpful surgical pearls.
Q: What are your general workup/diagnostic studies for a plantar foot puncture wound?
A: Molly Judge, DPM emphasizes obtaining a thorough medical history as well as a very concise account of the history of the puncture wound. All of the panelists recommend radiographs to rule out a retained foreign body. Depending on the clinical picture, Dr. Judge says one might use other, more detailed imaging studies but she notes these are not always necessary.
If the puncture occurred recently, Michael Keller, DPM, suggests obtaining radiographs and ultrasound views. If the puncture occurred several days prior to the appointment, Dr. Keller says an MRI might be relevant to rule out the possibility of osteomyelitis, especially if an infection is present. In the event of a retained foreign body, he says MRI or ultrasound views are relevant. If a metallic object has punctured the foot, Dr. Keller says plain films or fluoroscopy can provide “significant benefit.”
Dr. Judge adds that plain radiographs can also rule out soft tissue emphysema in these cases. Lawrence Karlock, DPM, points out that puncture wounds “notoriously have more soft tissue damage than what is noted superficially.”
With puncture wounds, blood work (including CBC, CMP, ESR and CRP) is indicated, according to Dr. Keller. Dr. Judge concurs, noting that CBC, CRP and creatinine are “the bare minimum for a healthy individual.” When it comes to patients with a chronic disease, Dr. Judge suggests checking electrolytes and disease specific chemistries. She says one should also check the patient’s HgbA1C if he or she has diabetes and the potential for poor disease control.
If there is any question of a retained foreign body or shoe/sock material within the wound, Dr. Karlock says one should explore the majority of these wounds. After she discusses possible medication allergies with patients, Dr. Judge performs an in-office incision and drainage as appropriate for the clinical picture. After a sterile prep, draping and nerve block, she debrides the wound, widens the portal of entry and explores for the foreign body.
After copious irrigation, Dr. Judge says there is now a reasonable setting for obtaining a deep wound culture. As she notes, a simple wound packing of plain 1/4-inch gauze strips and a sterile compressive dressing with surgical shoe is often sufficient to keep the region clean and dry.
Dr. Judge closely monitors puncture wounds and has patients return to the office in three days so she can review culture reports, modify antibiotics if necessary and consider timing for a delayed primary closure if indicated.
Q: How often do you utilize diagnostic ultrasound or MRI or bone scans in these cases?
A: As Dr. Keller notes, one can use diagnostic ultrasound to detect any loose foreign bodies deep in the soft tissues, particularly in early presentation. He stresses that ultrasound is highly dependent on the technician “and, for that reason, is often underutilized.”
For puncture wounds, Dr. Judge often uses ancillary imaging based upon the clinical presentation. For example, if she wants to retrieve a retained foreign body that is deeply seated, she uses ultrasound for guidance in the OR.
“It is often pretty simple to triangulate the location of the object using this modality and it obviates the need to use other more expensive techniques,” points out Dr. Judge.