The Effect of Positive Postdebridement Cultures on Local Muscle Flap Reconstruction of the Lower Extremity

Local surgery feasibility and safety after carbon ion radiotherapy for primary bone sarcomas

BACKGROUND

It is known that several complications are caused by local surgery after radiotherapy. Clinical reports that describe the postoperative complications associated with surgery after carbon ion radiotherapy are sparse. This study aimed to elucidate local surgery feasibility after carbon ion radiotherapy specifically for primary bone sarcomas.

METHODS

The medical, surgical, and irradiation records of patients who had local surgery at the area irradiated with carbon ion beams between 2004 and 2018 were reviewed retrospectively to evaluate the feasibility and indication of local surgery after CIRT.

RESULTS

There were eight patients who had 10 local surgeries at the irradiated sites among the 42 carbon ion radiotherapy patients. There were seven males and one female with a median age of 50 years (range 26-73 years). The reasons for surgery were three for skin toxicity and associated infection, five for bone collapse, and associated implant failure, and two for tumor regrowth. All surgical fields included the area of more than 60 Gy (RBE) irradiated dose. All three surgical cases caused by skin toxicity and associated infection had Grade I wound complication after surgery according to the Clavien-Dindo Classification.

CONCLUSION

Local surgery after CIRT appeared feasible in selected patients with primary bone sarcoma, especially for the patients with bone collapse and associated implant failure. However, infection and prescribed irradiation dose at the incision site must be carefully evaluated.

A Multidisciplinary Approach to End-Stage Limb Salvage in the Highly Comorbid Atraumatic Population: An Observational Study

Background: The use of free tissue transfer (FTT) is efficacious for chronic, non-healing lower extremity (LE) wounds. The four pillars of managing patient comorbidities, infection control, blood flow status, and biomechanical function are critical in achieving successful limb salvage. The authors present their multidisciplinary institutional experience with a review of 300 FTTs performed for the complex LE limb salvage of chronic LE wounds. Methods: A single-institution, retrospective review of atraumatic LE FTTs performed by a single surgeon from July 2011 to January 2023 was reviewed. Data on patient demographics, comorbidities, preoperative management, intraoperative details, flap outcomes, postoperative complications, and long-term outcomes were collected. Results: A total of 300 patients who underwent LE FTT were included in our retrospective review. Patients were on average 55.9 ± 13.6 years old with a median Charlson Comorbidity Index of 4 (IQR: 3). The majority of patients were male (70.7%). The overall hospital length of stay (LOS) was 27 days (IQR: 16), with a postoperative LOS of 14 days (IQR: 9.5). The most prevalent comorbidities were diabetes (54.7%), followed by peripheral vascular disease (PVD: 35%) and chronic kidney disease (CKD: 15.7%). The average operative LE FTT time was 416 ± 115 min. The majority of flaps were anterolateral thigh (ALT) flaps (52.7%), followed by vastus lateralis (VL) flaps (25.3%). The immediate flap success rate was 96.3%. The postoperative ipsilateral amputation rate was 12.7%. Conclusions: Successful limb salvage is possible in a highly comorbid patient population with a high prevalence of diabetes mellitus, peripheral vascular disease, and end-stage renal disease. In order to optimize patients prior to their LE FTT, extensive laboratory, arterial, and venous preoperative testing and diabetes management are needed preoperatively. Postoperative monitoring and long-term follow-up with a multidisciplinary team are also crucial for long-term limb salvage success.

Lower Extremity Microsurgery in a Patient With Combined Sickle Cell Disease and Hemophilia: A Case Report and Literature Review

The combination of hemophilia and sickle cell disease poses unique challenges in the perioperative management of patients requiring free tissue transfer (FTT). Extremity FTT requires mitigation of risk factors related to perioperative bleeding and microvascular thrombosis. This case report highlights the nuances of managing an open ankle fracture in a patient with both sickle cell trait and severe hemophilia A. The narrative and discussion highlights the importance of a multidisciplinary team with regard to executing a limb salvage plan in the setting of complex medical decision-making.

Outcomes of Local Versus Free Flaps for Reconstruction of the Proximal One-Third of the Leg

BACKGROUND

Reconstruction of the proximal one-third of the leg often requires soft tissue transfer to facilitate limb salvage. Tissue transfers are usually local or free flaps depending on wound dimensions, location, and surgeon preference. Historically, the proximal third of the leg was covered with pedicle flaps, but recently, we have used more free flaps in this position. Using data from a level 1 trauma center, we sought to evaluate outcomes of surgical management of proximal-third leg reconstruction across local and free flaps.

METHODS

This is an institutional review board-approved, retrospective chart review undertaken at LAC + USC Medical Center from 2007 to 2021. Patient history, demographics, flap characteristics, Gustilo-Anderson fracture classification, and outcomes were collected and analyzed in an internal database. Outcomes of interest included flap failure rates, postoperative complications, and long-term ambulatory status.

RESULTS

Among 394 lower extremity flaps placed, 122 flaps involved the proximal-third leg across 102 patients. Average age of patients was 42.8 ± 15.2 years; of note, the free flap cohort was significantly younger than the local flap cohort (P = 0.019). Ten local flaps suffered from infectious complications: osteomyelitis (n = 6) and hardware infection (n = 4), versus only 1 free flap that suffered from hardware infection; notably, these differences were not significant across cohorts. Free flaps had significantly more flap revisions (13.3%; P = 0.039) and overall flap complications (20.0%; P = 0.031) compared with local flaps; however, partial flap necrosis (4.9%) and flap loss (3.3%) were not significantly different across cohorts. Overall flap survival was 96.7%, and full ambulation was achieved in 42.2% of patients without significant differences across cohorts.

CONCLUSIONS

Our evaluation of proximal-third leg wounds demonstrates fewer infectious outcomes with free flaps compared with local flaps. There are multiple confounding variables; however, this finding may speak to the reliability of a robust free flap. Overall, there was no significant difference in patient comorbidities across flap cohorts with great overall flap survival. Ultimately, flap selection did not affect rates of flap necrosis, flap loss, or final ambulatory status.

Modified fourth lumbar artery local perforator flap: an alternative for reconstruction of nonhealing lumbosacral spinal defects

BACKGROUND

The reconstruction of nonhealing lumbosacral spinal defects remains a challenge, with limited options. The aim of this article was to review the authors' technique and experience with the modified fourth lumbar artery local perforator (MFLALP) flap for the coverage of nonhealing lumbosacral defects after spinal surgery.

METHODS

Between August 2012 and May 2021, we reviewed all MFLALP flaps performed for lumbosacral spinal defects. Patient demographics, wound aetiologies, surgical characteristics, and outcomes were reviewed retrospectively.

RESULTS

A total of 31 MFLALP flaps were performed on 24 patients during the research period. The median flap size was 152 cm² (range, 84-441 cm²). All flaps survived successfully, although there were two cases of minor complications. One patient had a haematoma and required additional debridement and skin grafting at 1 week postoperatively. The other patient suffered wound dehiscence at the donor site at 2 weeks postoperatively and required reclosure. The follow-up time ranged from 6 months to 5 years.

CONCLUSIONS

The MFLALP flap has the advantages of a reliable blood supply, sufficient tissue bulk and low complication rate. This technique is an alternative option for the reconstruction of nonhealing lumbosacral spinal defects.

Flap failure prediction in microvascular tissue reconstruction using machine learning algorithms

BACKGROUND

Microvascular tissue reconstruction is a well-established, commonly used technique for a wide variety of the tissue defects. However, flap failure is associated with an additional hospital stay, medical cost burden, and mental stress. Therefore, understanding of the risk factors associated with this event is of utmost importance.

AIM

To develop machine learning-based predictive models for flap failure to identify the potential factors and screen out high-risk patients.

METHODS

Using the data set of 946 consecutive patients, who underwent microvascular tissue reconstruction of free flap reconstruction for head and neck, breast, back, and extremity, we established three machine learning models including random forest classifier, support vector machine, and gradient boosting. Model performances were evaluated by the indicators such as area under the curve of receiver operating characteristic curve, accuracy, precision, recall, and F1 score. A multivariable regression analysis was performed for the most critical variables in the random forest model.

RESULTS

Post-surgery, the flap failure event occurred in 34 patients (3.6%). The machine learning models based on various preoperative and intraoperative variables were successfully developed. Among them, the random forest classifier reached the best performance in receiver operating characteristic curve, with an area under the curve score of 0.770 in the test set. The top 10 variables in the random forest were age, body mass index, ischemia time, smoking, diabetes, experience, prior chemotherapy, hypertension, insulin, and obesity. Interestingly, only age, body mass index, and ischemic time were statistically associated with the outcomes.

CONCLUSION

Machine learning-based algorithms, especially the random forest classifier, were very important in categorizing patients at high risk of flap failure. The occurrence of flap failure was a multifactor-driven event and was identified with numerous factors that warrant further investigation. Importantly, the successful application of machine learning models may help the clinician in decision-making, understanding the underlying pathologic mechanisms of the disease, and improving the long-term outcome of patients.

Amputation versus Free Flap: Long-Term Outcomes of Microsurgical Limb Salvage and Risk Factors for Amputation in the Diabetic Population

BACKGROUND

Reconstructive microsurgery is an effective limb-saving option for nonhealing lower extremity wounds in diabetic patients. However, the ability to predict the future need for amputation is unclear. This article seeks to identify risk factors for amputation following microsurgical free tissue transfer in the diabetic lower extremity.

METHODS

Diabetic patients undergoing lower extremity free flap surgery between August of 2011 and January of 2018 performed by a single surgeon were identified retrospectively. Patient comorbidities, reconstructive conditions and flap traits, microsurgical outcomes, and long-term outcomes were examined. Variables conferring risk for future amputation were examined by means of regression analysis.

RESULTS

Sixty-four patients met the criteria. The overall immediate flap success rate was 94 percent (60 of 64). Long term, 50 patients (78.1 percent) underwent successful salvage, and 14 patients (21.9 percent) required major amputation. Acute flap loss resulted in four amputations, and delayed complications (hematoma, infection, recurrent nonhealing) resulted in 10 amputations. The average time to amputation was 5.6 months. Risk factors for amputation were end-stage renal disease (OR, 30.7; p = 0.0087), hindfoot wounds (OR, 4.6; p = 0.020), elevated hemoglobin A1C level greater than 8.4 percent (OR, 1.4; p = 0.05), and positive wound cultures (OR, 6.1; p = 0.003).

CONCLUSIONS

Multiple comorbidities and poor glucose control were identified as risk factors for amputation after free flap limb salvage. However, successful limb preservation is possible.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Day-of-Free Tissue Transfer Qualitative Cultures Do Not Predict Limb Salvage Outcomes

BACKGROUND

Successful free tissue transfer is critical for lower extremity salvage in the chronic wound population. The rates of lower extremity free tissue transfer success lag behind those for other anatomical sites. The aim of this study was to evaluate whether positive qualitative day-of-free tissue transfer cultures or pathogen virulence negatively impacts short- and long-term outcomes of lower extremity free tissue transfer.

METHODS

Between April of 2011 and January of 2018, 105 lower extremity free tissue transfer procedures were performed. Growth level and speciation were identified from qualitative cultures taken during free tissue transfer. The relationship between demographics, comorbidities, culture data, postoperative infection, free tissue transfer survival, and long-term limb salvage was examined using logistic regression.

RESULTS

The median Charlson Comorbidity Index was 3. Intraoperative free tissue transfer cultures were positive in 39.1 percent. Flap survival was 93.3 percent. Postoperative infection developed in 12.4 percent. The limb salvage rate was 81.0 percent. Positive culture was not significant for flap survival, postoperative infection, or amputation. Cultures positive for Enterococcus species had a significant relationship with flap success (OR, 0.08; p = 0.01) and amputation (OR, 7.32; p = 0.04). Insufficient antimicrobial coverage had a significant relationship with postoperative infection (OR, 6.56; p = 0.01) despite the lack of pathogen concordance. On multivariate analysis, postoperative infection (OR, 12.85; p < 0.01) and Charlson Comorbidity Index were predictive of eventual amputation (OR, 1.44; p = 0.01).

CONCLUSIONS

Positive day-of-free tissue transfer cultures, regardless of pathogen, had limited predictive value for short- and long-term outcomes of free tissue transfer in the authors' cohort. These findings call for a broader multicenter prospective analysis and consideration of health care-associated infections and their impact on limb salvage outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

The Need to Improve Patient-Centered Outcome Reporting Following Lower Extremity Flap Reconstruction: A Systematic Review and Meta-analysis

INTRODUCTION

 Research in lower extremity (LE) wound management involving flap reconstruction has primarily focused on surgeon-driven metrics. There has been a paucity in research that evaluates patient-centered outcomes (PCO). This systematic review and meta-analysis examines articles published between 2012 and 2020 to assess whether reporting of functional and quality of life (QOL) outcomes have increased in frequency and cohesiveness, compared with the previous two decades.

METHODS

 PubMed and Ovid were queried with appropriate Medical Subject Heading (MeSH) terms for studies published between June 2012 and July 2020. For inclusion, each study had to report any outcome of any tissue transfer procedure to the LE in comorbid patients, including complication rates, ambulation rates, flap success rates, and/or QOL measures. The PCO reporting prevalence was compared with a previous systematic review by Economides et al which analyzed papers published between 1990 and June 2012, using a Pearson's Chi-squared test.

RESULTS

 The literature search yielded 40 articles for inclusion. The proportion of studies reporting PCO was greater for literature published between 1990 and 2012 compared with literature published between 2012 and 2020 (86.0 vs. 50.0%, p < 0.001). Functional outcomes were more commonly reported between 1990 and 2012 (78.0 vs. 47.5%, p = 0.003); similarly, ambulatory status was reported more often in the previous review (70.0 vs. 40.0%, p = 0.004). This study solely examined the rate at which PCO were reported in the literature; the individual importance and effect on medical outcomes of each PCO was not evaluated.

CONCLUSION

 Less than 50% of the literature report functional outcomes in comorbid patients undergoing LE flap reconstruction. Surprisingly, PCO reporting has seen a downward trend in the past 8 years relative to the preceding two decades. Standardized inclusion of PCO in research regarding this patient population should be established, especially as health care and governmental priorities shift toward patient-centered care.

Case Report: Surgical Closure of Chronic Soft Tissue Defects Using Extracellular Matrix Graft Augmented Tissue Flaps

Chronic soft tissue defects are notoriously difficult to heal. Surgical reconstruction of chronic defects using tissue flaps is a routine approach for closure of challenging chronic defects. Due to the poor tissue quality of chronic defects and associated inflammation, infection and impaired blood supply the success of flap closure is marred by reported complication rates of 25-58%. Extracellular matrix (ECM)-based graft materials are commonly used for resolving chronic wounds and in plastic and reconstructive procedures to create a scaffold for tissue regeneration. We hypothesized combination use of ECM grafts with tissue flaps in a single-stage surgical procedure would reduce complications and improve outcomes in the closure of chronic soft tissue defects. We report a case series (n = 9) of chronic soft tissue defect reconstruction using this modified procedure of ECM graft augmented flap closure. Defects included pressure injuries and surgical dehiscence and ranged in wound age from 5 months to 7 years. Successful uncomplicated healing was achieved in six defects. Post-operative complications (dehiscence) occurred in two defects, however, these healed via secondary intention without additional surgical intervention. All healed defects exhibited acceptable cosmesis and "normal" function, with 100% patient satisfaction. Augmentation of tissue flaps with ECM graft materials in this modified single-stage procedure may improve outcomes and minimize typical complications encountered in flap closure of chronic defects attributed to inflammation, infection, hypoperfusion, and dead space.

Complex Lower Extremity Wound in the Complex Host: Results From a Multicenter Registry

Background:

The complex diabetic lower extremity wound has not been well studied. There are a variety of new technologies now being applied with a paucity of evidence in evaluating their outcomes. The aim of this study is to describe clinical outcomes in the complex lower extremity wound in the comorbid host. We hypothesized that treatment choice would have minimal impact on healing outcomes in this compromised population.

Methods:

A multicenter retrospective registry of patients with diabetes and lower extremity wounds was created to compare treatment modalities of collagen–glycosaminoglycan scaffold, negative-pressure wound therapy, local tissue flap, and free tissue transfer. Statistical analyses included descriptive, proportional comparisons and Cox regression.

Results:

There were no statistical differences in age, hemoglobin A1c, or body mass index between groups. Study patients had a history of amputation (40.5%), peripheral vascular disease (54.6%), peripheral neuropathy (64.8%), end-stage renal disease (13.9%), renal/hepatic disease (40.4%), and hypertension (85%). The most common wound etiologies were surgical dehiscence (69%), diabetic neuropathic wounds (39%), and ischemic wounds (28%), most commonly located on the foot or at a prior amputation site (30%). Mean wound area was 57.9 cm² and almost half with exposed bone. There were no statistical differences between treatment groups in proportion or time to healing, recurrence, or time to return to baseline function.

Conclusions:

Commonly used treatment modalities employed for this population of patients resulted in similar outcomes. This is the first study to describe the complex diabetic lower extremity wound in a complex host.