See Table 1.
Case 1. Mr. H, a 71-year-old patient, presented to the emergency department with a history of hypertension controlled with lisinopril. He had fallen from a tall tree 7 days before presentation. An x-ray and CT scan showed an uncomplicated supracondylar humeral fracture with dislocation (AO-classification 13- C1). An open reposition and internal fixation was performed 17 days after the accident, delayed due to severe soft tissue swelling. Fixation was performed using double plating with distal humeral plates (DePuy Synthes, Zeist, The Netherlands).
Six (6) days after surgery, Mr. H presented to the emergency department with a fever and pain at the surgical site. Infection parameters were elevated (CRP 211 mg/L, leukocytes 10.8 10^9/l). Due to the combination of pain, illness, and elevated infection parameters in laboratory tests, a postoperative wound infection (POWI) was diagnosed. Mr. H was admitted to the hospital and antibiotic therapy using flucloxacillin IV, 6 g/24 hours, was started. Despite 3 days of antibiotic therapy, surgical exploration was required around the fixation site due to ongoing redness, swelling, and pain. Pus was drained, and the wound edges were approximated over gentamycin beads. A wound culture showed S aureus sensitive for flucloxacillin.
Three (3) days after removal of pus at the surgical site, the gentamycin-beads were removed and NPWTi-d was applied. The wounds were instilled as described. After 5 days of NPWTi-d, rapid granulation of the wound was seen (see Figure 1). At that time, the infection parameters had returned to almost normal values (CRP 31 mg/L, leukocytes 6.1x10^9/L). After 12 days, the NPWTi-d was changed to a NPWT system and Mr. H was discharged 21 days after re-admission (see Figure 2). The NPWT was continued at home without antibiotic therapy. After 1 month, a split skin graft was performed to close the wound. The skin graft was managed using NPWT for 5 days. Epithelialization of the wound and good adhesion of the graft (see Figure 3) were noted after removal of the NPWT system. Follow-up at 6 months showed no further complications, with a good function of the elbow. No adverse events occurred during wound treatment.
Case 2. Otherwise healthy 49-year-old Ms. K fell off her bike onto the sidewalk. (A few years before this accident, she had a correction of her hammertoes.) She suffered an uncomplicated fracture of the tibia plateau (Schatzker classification 6). Nine (9) days after the trauma, she underwent open reposition and internal fixation using a tibia-locking compression plate. The postoperative x-ray and CT scan 1 day after surgery showed a persistent depression of the lateral tibia plateau, necessitating reoperation during which the depression was corrected and the plate replaced. The skin was closed over a gentamycin-collagen resorbable dressing using staples. The surgeon provided 3 doses of antibiotics postoperatively (cefazolin IV, 1500 mg, over 24 hours) because of the estimated higher risk of infection; this was not a standard procedure.
When Ms. K went for follow-up in the outpatient clinic 14 days later, a wound infection was diagnosed. Wound cultures showed S aureus infection with no resistance for flucloxacillin. Multiple surgical wound debridements, NPWT, and long-term antibiotic treatment over 4 months had no effect. Despite lateral gastrocnemius transposition to close the wound, the infection persisted.
Six (6) months later, Ms. K was admitted with a persistent infection of the tibial plate (see Figure 4). Surgical debridement was performed and NPWTi-d was used to cover the wound combined with antibiotic therapy using intravenous flucloxacillin, 6 g/day, for 5 weeks. The wound was instilled with polyhexanide biguanide, and NPWTi-d was provided as described. After 3 weeks, the wound was fully granulated (see Figure 5) and NPWT continued without the instill option. After 2 more weeks, the wound was closed (see Figure 6). Infection did not recur during the follow-up, and 6 months later the orthopedic surgeon successfully placed a total knee prosthesis, due to functional limitations. Six (6) months of follow-up by the orthopedic surgeon showed no infection or complications of the knee prosthesis placement. No adverse events occurred during wound treatment.
Case 3. Ms. L, a 64-year-old with a medical history including alcohol abuse and Korsakoff syndrome with severe memory impairment, presented to the emergency room 6 weeks after an inversion trauma of the left ankle. Her only noted medication was thiamine; her health was otherwise normal.
X-rays showed a trimalleolar ankle fracture. Ms. L was admitted to the hospital, and conservative treatment with cast therapy was started due to severe soft tissue swelling. During admission, Ms. L’s condition improved and an open reduction and internal fixation was performed using a tritubular plate (DePuy Synthes, Zeist, The Netherlands) on the lateral side. No fixation on the medial side was performed due to soft tissue problems. A cast was placed postoperatively, and Ms. L was advised to avoid weight-bearing while ambulating. Despite this advice, Ms. L stood on her left ankle and x-ray studies showed a progressive subluxation of the talar bone with bowing of the fibular plate.
Eighteen (18) days after the first operation, redo surgery was performed using 2 plates on top of each other on the fibula and an extra Drittelrohr plate at the dorsal side of the fibula. The medial fracture was fixated with tension band wiring. The lateral wound could not be closed due to soft tissue problems. NPWTi-d was placed (see Figure 7) and the wound was instilled with polyhexanide biguanide, with dwell time and NPWT provided as described.
Wound cultures of the medial wound showed normal dermal bacteria (ie, no specific growth of any type). Intravenous prophylactic antibiotic treatment was started using flucloxacillin, 4 g/day. After 4 weeks, granulation tissue completely covered the plate. Instill therapy was changed to NPWT (see Figure 8). Two (2) weeks later, NPWT was discontinued because the wound was fully granulated.
Ms. L died a few weeks after she was discharged from the hospital. It was believed chronic alcohol abuse and cerebral complications of Korsakoff syndrome led to her death. In this patient, Korsakoff syndrome was a big risk factor in developing a wound infection. Because she could not remember to avoid weight-bearing on her operated ankle, the implant was bent, necessitating a second operation, which is associated with a higher risk of infection.14 No adverse events occurred during wound treatment.
Case 4. Ms. M is 59 years old and presented to the outpatient orthopedic clinic with a pressure ulcer at the medial malleolus, a compression ulcer related to the valgus position of the foot. Ms. M had undergone an ankle prosthesis placement due to rheumatoid arthritis (for which she used methotrexate) 5 years before. Additional medication included aspirin, a beta-blocker, and a statin. Ms. M also suffered from a normocytic anemia caused by chronic illness. On presentation, she used carbasalate calcium, a beta-blocker, a statin, omeprazole, and vitamin B tablets.
Corrective osteotomy was performed through medial and lateral incisions. Prophylactic antibiotics were provided postoperatively for 24 hours. After 4 weeks, a wound infection developed at the lateral surgical wound. The plate was visible after surgical debridement (see Figure 9). Antibiotic treatment was started using intravenous flucloxacillin, 6 g/day. Wound cultures showed S aureus and an Escherichia coli infection.
NPWTi-d therapy was started on the lateral wound. The hypothesis was the NPWTi-d would be able to temper bacterial counts and reduce the biofilm presumed to be present on the hardware. If the infection could not be treated, amputation of the lower leg was the last resort. The wound was instilled with polyhexanide biguanide, and dwell time and NPWT were provided as previously described during admission. Due to an allergic reaction to the flucloxacillin, Ms. M’s antibiotic therapy was switched to vancomycin. The medial and lateral wounds closed without complications and demonstrated granulation tissue (see Figures 10 and 11). After 5 weeks of NPWTi-d, therapy was changed to a low pressure, portable NPWT system for another 120 days until full closure (see Figure 12). The antibiotic treatment was continued for 6 months. After 10 months of follow-up, both wounds were fully closed without signs of infection (see Figure 13). No adverse events occurred during wound treatment.