The Role of Negative-Pressure Wound Therapy in Lower-Limb Reconstruction

Comparison of the effects of negative pressure wound therapy and negative pressure wound therapy with instillation on wound healing in a porcine model

Background

Negative pressure wound therapy with instillation (NPWTi) is a novel method based on standard negative pressure wound therapy (NPWT). This study aimed to compare the effects of standard NPWT and NPWTi on bioburden and wound healing in a Staphylococcus aureus (S.aureus) infected porcine model.

Methods

Green fluorescent protein-labeled S.aureus infected wounds were created on the back of porcine. Wounds were treated with NPWT or NPWT with instillation (saline). The tissue specimens were harvested on days 0 (12 h after bacterial inoculation), 2, 4, 6, and 8 at the center of wound beds. Viable bacterial counts, laser scanning confocal microscopy, PCR, western blot, and histological analysis were performed to assess virulence and wound healing.

Results

The bacterial count in the NPWTi group was lower than that of the NPWT group and the difference was statistically significant on day 2, day 4, day 6, and day 8 (P < 0.05). The expression levels of agrA, Eap, Spa, and Hla genes of the NPWTi group were significantly lower than that of the NPWT group on day 8 (P < 0.05). The bacterial invasion depth of the NPWTi group was significantly lower than that of the NPWT group on day 2, day 4, day 6, and day 8 (P < 0.05). Though the NPWTi group showed a significantly increased expression of bFGF and VEGF than that of the NPWT group in the early time (P < 0.05), NPWTi cannot lead to better histologic parameters than the NPWT group (P > 0.05).

Conclusion

Our results demonstrated that NPWTi induced a better decrease in bacterial burden and virulence compared with standard NPWT. These advantages did not result in better histologic parameters on the porcine wound model.

Complications of the surgical treatment of fractures of the tibial plateau: prevalence, causes, and management

Open reduction and internal fixation is the gold standard treatment for tibial plateau fractures. However, the procedure is not free of complications such as knee stiffness, acute infection, chronic infection (osteomyelitis), malunion, non-union, and post-traumatic osteoarthritis. The treatment options for knee stiffness are mobilisation under anaesthesia (MUA) when the duration is less than 3 months, arthroscopic release when the duration is between 3 and 6 months, and open release for refractory cases or cases lasting more than 6 months. Early arthroscopic release can be associated with MUA. Regarding treatment of acute infection, if the fracture has healed, the hardware can be removed, and lavage and debridement can be performed along with antibiotic therapy. If the fracture has not healed, the hardware is retained, and lavage, debridement, and antibiotic therapy are performed (sometimes more than once until the fracture heals). Fracture stability is important not only for healing but also for resolving the infection. In cases of osteomyelitis, treatment should be performed in stages: aggressive debridement of devitalised tissue and bone, antibiotic spacing and temporary external fixation until the infection is resolved (first stage), followed by definitive surgery with grafting or soft tissue coverage depending on the bone defect (second stage). Intra-articular or extra-articular osteotomy is a good option to correct malunion in young, active patients without significant joint damage. When malunion is associated with extensive joint involvement or the initial cartilage damage has resulted in knee osteoarthritis, the surgical option is total knee arthroplasty.

Evaluation of effectiveness of a new treatment method for healing infected wounds: an animal model

OBJECTIVE

To evaluate the effectiveness of a new treatment method in healing superficial infected wounds compared with surgical debridement with chlorhexidine solution.

METHOD

In this animal model, two wounds were created on the back of 10 male adult rabbits. Wounds treated by Method 1 were debrided using 0.02% chlorhexidine aqueous solution and an antibiotic topical ointment. Wounds treated by Method 2 wounds were treated using a newly developed device which enabled visual monitoring of the wound as it was treated with various pharmacological solutions (including antiseptic, antiseptic oxidant and an osmotically active agent) specifically formulated for each wound healing stage. Wound area size (using digital planimetry) and time taken to clean the wound were recorded, and biopsies were taken, at the beginning of the study and at various timepoints throughout.

RESULT

It was observed that both wound cleaning and wound healing were accelerated by treatment with method 2 compared with method 1 (by 43.8% and 36.7%, respectively). There were also a significantly smaller number of complications in these wounds [p=0.0044] due to the positive ratios of neutrophils and fibroblasts in the wound cavities (from the third to the fourteenth day after wound modelling).

CONCLUSION

Wounds treated with the new device in method 2 had a shorter wound healing time than wounds treated with a traditional method. The automated influx-outflow of solutions removed any fragments of necrotic tissue from the wound surface. Wounds were able to be monitored without the need to remove dressings. The transparent, airtight film, which allowed for wound monitoring without the need to remove dressings, meant that suturing was not required. This resulted in no complications in the wounds treated by this new method.

Manejo de heridas traumáticas de difícil cicatrización con colgajos microvasculares

OBJECTIVE

Present different flap alternatives when performing microvascular free-flap reconstruction in acute hard-to-heal wounds.

METHOD

A retrospective review of patients whose acute hard-to-heal wounds were treated with microvascular free-flap reconstruction. Data on demographics, wound aetiology, diagnostic, previous treatment, free-flap type, free-flap size, complications and follow up were analysed.

RESULTS

A total of 20 patients received microvascular free-flap reconstruction. The median age was 39.5 years. Twenty free-flap reconstructions were performed. These included: 3 cross-leg free flap, 1 cross-leg vascular cable bridge flap, 2 fibula osteocutaneous flap, 6 anterolateral thigh (ALT) flap, 3 thoracodorsal artery perforator (TDAP) flap, 3 fasciomyocutaneous flap, and 2 femoral artery fasciocutaneous flap. A patient required microvascular anastomosis due to hematoma; the rest did not present complications during their postoperative. Previous treatment included negative pressure wound therapy (12 patients) and surgical debridement with silver hydrogel dressings (8 patients).

CONCLUSION

Hard-to-heal wounds can be unresponsive to traditional wound healing practices or local flaps. They often require free-flap reconstruction, using tissues similar to those compromised. Microvascular techniques can be an effective alternative.

Reconstruction of Large Area of Deep Wound in the Foot and Ankle with Chimeric Anterolateral Thigh Perforator Flap

Objective

To evaluate the clinical application and surgical efficacy of the chimeric perforator flap pedicled with the descending branch of the lateral circumflex femoral artery and the lateral thigh muscle flap for the reconstruction of the large area of deep wound in foot and ankle.

Methods

Clinical data of 32 cases who underwent chimeric anterolateral thigh perforator flap to repair the large area of deep wound of the foot and ankle from January 2015 to December 2018 were retrospectively analyzed. The sizes of the defects ranged from 18 cm × 10 cm to 35 cm × 20 cm, with exposed tendon and bone and/or partial defects and necrosis, contaminations, accompanied by different degrees of infection. Following the radical debridement and VSD, chimeric anterolateral thigh perforator flap was employed to repair the deep wounds according to the position, site and deep‐tissue injury of the soft‐tissue defects. The skin flap and muscle flap were fanned out on the wound, and single‐ or two‐staged split‐thickness skin grafting was performed on the muscle flap. The operation time and blood loss were recorded. The survival and healing conditions of the operational site with chimeric anterolateral thigh perforator flap were evaluated post‐operationally. Complications at both recipient site and donor site were carefully recorded.

Results

The mean time of the operation was 325.5 min and average blood loss was 424.8 mL. Among the 32 cases, two cases developed vascular crisis, which were alleviated with intensive investigation and treatment; Four cases suffered from partial necrosis of the flap or skin graft on the muscle flap or on the residual local wound, which were improved after treatment of further dressing change and skin grafting. Another four cases experienced post‐traumatic osteomyelitis accompanied by bone defect were treated with simple bone grafting or Mesquelet bone grafting at 6–8 months after wound healing. Postoperatively, the wounds were properly healed, and the infection was effectively controlled without sinus tract forming. Overall, all 32 cases received satisfactory efficacy, without influencing subsequent functional reconstruction, and observed infection during the 12–36 months post‐operational follow‐up.

Conclusion

The chimeric perforator flap pedicled with the descending branch of the lateral circumflex femoral artery and the lateral thigh muscle flap provides an effective and relative safe procedure for the repair of a large area of deep wound in the foot and ankle, particularly with irregular defect or deep dead space.

Challenges and Management in Wound Care

SUMMARY

Wounds have been one of the most prominent pathologies since the beginning of humanity. For the last 5 decades, a drastic improvement of healing has been observed, thanks to new medical devices based on fluid aspiration capacities and the development of negative pressure wound therapy. Negative-pressure wound therapy was initially designed for a double action, fluid aspiration and mechanical stimulation of wound edges by a foam. Successive technical evolutions of negative pressure wound therapy were declined since 1997 when Argenta and Morykwas first presented their solution. The adjunct of instillation in 2009 was considered as the first interactive dressing, allowing topical wound solutions to sequentially reach the wound, in alternance with negative pressure. Other devices based on the same principle were designed to prevent postoperative infections when placed over a suture after surgery. This long evolution could enhance the armamentarium of possible solutions, considerably reducing the wound healing time.

Soft tissue management in open tibial shaft fractures: A comparison of institutional preferences and resultant early clinical outcomes

Aims

To compare results of institutional preferences with regard to treatment of soft tissues in the setting of open tibial shaft fractures.

Methods

We present a retrospective review of open tibial shaft fractures at two high-volume level 1 trauma centres with differing practices with regard to the acute management of soft tissues. Site 1 attempts acute primary closure, while site 2 prefers delayed closure/coverage. Comparisons include percentage of primary closure, number of surgical procedures until definitive closure, percentage requiring soft tissue coverage, and percentage of 90-day wound complication.

Results

Overall, there were 219 patients at site 1 and 282 patients at site 2. Differences in rates of acute wound closure were seen (168 (78%) at site 1 vs 101 (36%) at site 2). A mean of 1.5 procedures for definitive closure was seen at site 1 compared to 3.4 at site 2. No differences were seen in complication, nonunion, or amputation rates. Similar results were seen in a sub-analysis of type III injuries.

Conclusion

Comparing outcomes of open tibial shaft fractures at two institutions with different rates initial wound management, no differences were seen in 90-day wound complications, nonunion rates, or need for amputation. Attempted acute closure resulted in a lower number of planned secondary procedures when compared with planned delayed closure. Providers should consider either acute closure or delayed coverage based on the injury characteristics, surgeon preference and institutional resources without concern that the decision at the time of index surgery will lead to an increased risk of complication.

Cite this article: Bone Joint Open 2020;1-8:481–487.

Manejo de heridas traumáticas de difícil cicatrización con colgajos microvasculares

OBJECTIVE

Present different flap alternatives when performing microvascular free-flap reconstruction in acute hard-to-heal wounds.

METHOD

A retrospective review of patients whose acute hard-to-heal wounds were treated with microvascular free-flap reconstruction. Data on demographics, wound aetiology, diagnostic, previous treatment, free-flap type, free-flap size, complications and follow up were analysed.

RESULTS

A total of 20 patients received microvascular free-flap reconstruction. The median age was 39.5 years. Twenty free-flap reconstructions were performed. These included: 3 cross-leg free flap, 1 cross-leg vascular cable bridge flap, 2 fibula osteocutaneous flap, 6 anterolateral thigh (ALT) flap, 3 thoracodorsal artery perforator (TDAP) flap, 3 fasciomyocutaneous flap, and 2 femoral artery fasciocutaneous flap. A patient required microvascular anastomosis due to hematoma; the rest did not present complications during their postoperative. Previous treatment included negative pressure wound therapy (12 patients) and surgical debridement with silver hydrogel dressings (8 patients).

CONCLUSION

Hard-to-heal wounds can be unresponsive to traditional wound healing practices or local flaps. They often require free-flap reconstruction, using tissues similar to those compromised. Microvascular techniques can be an effective alternative.