In the Lab

Fox is nationally and internationally known for her work to restore hand and upper extremity function in the setting of mid-cervical level spinal cord injury (SCI). Her primary research interests highlight and build upon this clinical work. She has established the protocol for the perioperative testing and counseling of people with cervical level spinal cord injury who are considering nerve transfer surgery in this setting. This novel application of a well-established technique — peripheral nerve transfer surgery — to improve upper extremity and hand function in people with cervical level SCI may significantly expand treatment options in this arena.

Her dedicated, multidisciplinary research team are on a mission to significantly expand treatment options for cervical level spinal cord injuries.

Research in this lab is currently focused on:

• Further defining surgical candidacy and clinical outcomes for peripheral nerve transfer surgery
• Assessment of perception of surgical and nonsurgical interventions
• Development and testing of surgical decision aid comparing nerve and tendon transfer surgery and nonsurgical intervention
• Outreach and education of health care providers, people spinal cord injuries and surrounding communities

A U.S. Department of Defense Grant funds her research work. The Craig H. Neilsen Foundation has funded her research in the past.

Li’s research focuses on developing bioengineered materials that promote tissue healing, regeneration, and functional recovery. His group integrates polymer chemistry, biomaterials engineering, cell biology, and clinically relevant animal models to address unmet surgical needs, including ischemic tissue injury, wound closure, and vascular reconstruction. By designing materials that modulate oxidative stress and inflammation, enable localized therapeutic delivery, and support tissue repair and integration, the group seeks to translate fundamental engineering discoveries into practical therapies that improve patient outcomes.

Regenerative biomaterials for ischemic tissues

Peripheral artery disease (PAD) causes chronic limb ischemia, oxidative stress, and progressive skeletal muscle damage that can persist even after blood flow is restored. In collaboration with Justin Sacks, MD, MBA, and Mohamed Zayed, MD, PhD, MBA, Li is developing an injectable, redox-responsive composite that locally delivers antioxidative biomaterials and pro-regenerative signals. This therapy is designed to neutralize harmful reactive oxygen species, promote vascular regeneration, preserve ischemic muscle, and restore limb function and walking capacity. The platform is being optimized through in vitro studies and evaluated in rat and swine models of PAD to support future clinical translation.

Surgical adhesives for wound closure and seroma prevention

Surgical procedures that separate large tissue surfaces can create dead space where fluid accumulates, potentially leading to seroma formation. Existing prevention methods, including drains and tension sutures, can cause discomfort, increase infection risk, damage tissue, and prolong postoperative care. In collaboration with Matthew Wood, PhD, and Justin Sacks, MD, MBA, Li is engineering bioactive composite meshes that securely adhere to internal tissues through complementary hydrogen and covalent bonding. By closing dead space while promoting vascularization, modulating inflammation, and supporting tissue integration, this technology aims to provide a regenerative and durable alternative for wound closure and seroma prevention across reconstructive, aesthetic, and general surgical procedures.

Sutureless devices for arterial anastomosis and hemodialysis access

Connecting small and large blood vessels is essential in reconstructive, vascular, transplant, hand, neurosurgical, and maxillofacial procedures, as well as in the creation of vascular access for hemodialysis. However, conventional suturing is technically demanding, time-consuming, and susceptible to thrombosis and other complications. To address these challenges, Li, in collaboration with Justin Sacks, MD, MBA, Mohamed Zayed, MD, PhD, MBA, and Guy Genin, PhD, SM, MS, is developing 3D-printed, intraluminal devices that create rapid and secure vascular connections without full-thickness penetration of the vessel wall. The team is optimizing device geometry and biofunctional surfaces to preserve blood flow, minimize endothelial injury, promote vascular healing, and maintain long-term patency. Through computational modeling, benchtop testing, and clinically relevant porcine studies, this research aims to develop vascular-connection technologies that make arterial reconstruction and hemodialysis access procedures faster, more consistent, and more accessible.

Mackinnon leads clinical research to advance the management of nerve-injured patients. Mackinnon also is pursuing video-based learning and coaching in nerve surgery, not only to include nerve surgeries themselves, but also to include the component of clinical judgment and patient selection, which is critical to patient safety and quality improvement outcomes.

Terence Myckatyn, MD, a professor of plastic and reconstructive surgery at WashU Medicine, leads many multidisciplinary research endeavors related to breast and aesthetic surgery. His current research includes the following:

• Shared decision-making in breast reconstruction
  Working with collaborators Mary Politi, PhD; Hedwig E. Lee, MA, PhD; Randi Foraker, PhD, MA, FAHA, FAMIA; and Margaret Olsen, PhD, MPH, Myckatyn has developed a web-based clinical decision aid to facilitate shared decision-making in breast reconstruction. 
• Randomized control trial to compare acellular dermal matrices
  Working with Marissa Tenenbaum, MD, Myckatyn is conducting an industry-funded study that compares surgical and patient-reported outcomes between two forms of acellular dermal matrices used in pre- and post-pectoral breast reconstruction.
• Randomized control trial to compare impact of antibiotic irrigation and cancer on microbiota of tissue expanders
  This study, funded by the Plastic Surgery Foundation, uses next-generation sequencing and advanced microbiological techniques to analyze the impact of cancer and antibiotic irrigation on bacterial biofilm formation on breast-tissue expanders. This work is performed in collaboration with Jennifer Walker, MD, and Blake Hanson, MD, at the University of Texas Health Science Center at Houston (UTHealth).
• Analysis of agglutination around breast implants
  This study, funded by the Plastic Surgery Foundation, explores the formation of bacterial agglutinins around breast implants, a transition phase between planktonic and biofilm bacteria, and a potential therapeutic target to prevent device-related infection. This work is performed in collaboration with Jennifer Walker, MD, and Blake Hanson, MD, at the University of Texas Health Science Center at Houston (UTHealth).
• Genomics of breast implant-associated anaplastic large cell lymphoma
  This study, funded by the Aesthetic Surgery Education Research Foundation, explores a potential genetic predisposition to development of BIA-ALCL in patients with macro-textured breast implants, utilizing both whole genome and whole exome sequencing, FISH and other genomic techniques. This work is performed in conjunction with pathology and immunology specialist Eric Duncavage, MD, and oncology specialist Neha Mehta-Shah, MD, at WashU Medicine.
• Metabolics of breast implant bacteria
  This study investigates whether particular small molecules identifiable in seroma fluid around breast implants can diagnose or predict a clinically relevant infection in some cases, or portend a benign scenario in other cases. This work is performed in conjunction with infectious diseases specialists Margaret A. Olsen, PhD, MPH, and Jeffrey P. Henderson, MD, PhD, at WashU Medicine.

Patel works at the forefront of craniosynostosis and cleft lip and/or palate research, leading a craniofacial and pediatric research lab. This multidisciplinary lab’s groundbreaking work has demonstrated the success of a novel approach to craniosynostosis surgery and continues work to advance pediatric reconstructive research. His work is supported by Children’s Hospital Foundation.

Currently, Patel’s lab focuses on:

• Optimizing value-based multidisciplinary team care for patients with cleft lip and/or palate to significantly reduce patient wait time and unnecessary clinic visits without compromising patient care
• Measuring neurodevelopmental outcomes following endoscope-assisted repair of craniosynostosis
• Imaging skull bones via MRI to eliminate the risk of brain cancer from CT radiation
• Anthropometric and patient-reported outcomes in patients with congenital craniofacial conditions. This work focuses on the interplay between physical appearance and psychological and social factors, taking patient and parent perspectives into account to transform patient care.

Pet develops and validates soft, wireless, and biointegrated technologies that provide real-time physiologic insight to improve diagnosis, perfusion monitoring, and rehabilitation in reconstructive and hand surgery. Pet is an Associate Professor of Surgery specializing in hand and wrist surgery, microvascular and nerve reconstruction, and complex cancer and trauma reconstruction.
His group’s vision is to advance patient care by developing equitable, data-driven tools that help surgeons monitor perfusion, evaluate tissue viability, and guide postoperative recovery. By uniting surgical expertise with advanced engineering, they integrate bench-top device design, preclinical large-animal validation, and clinical trials to translate meaningful innovation into patient care. Work is strengthened by close collaborations with engineers at WashU Medicine, as well as external academic partners and industry teams.

• Biosensors for tissue oxygenation, perfusion, and metabolism
  His group develops and validates soft, wireless, multimodal biosensors that provide continuous, high-resolution measurements of key physiologic parameters, including oxygenation, microvascular perfusion, pressure, pH, and metabolic status. These devices support applications such as free flap monitoring, compartment syndrome detection, and real-time assessment of tissue viability. These innovations advance from device design to large-animal validation to ensure that the resulting monitoring technologies are clinically meaningful and ready for translation.
• Impact of skin pigmentation on optical biosensing devices
  Light-based sensors, such as pulse oximeters and NIRS tissue oxygenation devices, measure light after it passes through the skin, where melanin strongly absorbs both visible and near-infrared wavelengths. Higher melanin levels reduce the detected signal and can produce systematically biased readings in darker skin. To address this equity gap, they validated both a bicolor porcine flap model and a systemic deoxygenation model using pigs with adjacent pigmented and non-pigmented skin, enabling controlled assessment of pigmentation effects on device accuracy. Leveraging these models, they are working toward melanin-agnostic optical biosensors that provide reliable physiologic monitoring across all skin tones.
• Device testing from bench to bedside
  His group is conducting a pilot clinical trial evaluating a next-generation wearable, wireless NIRS sensor for free flap monitoring designed to overcome limitations of the wired clinical gold standard, the ViOptix T.Ox system. By stability and workflow compatibility, this device aims to deliver accurate, continuous flap monitoring. After previous validation in our preclinical animal models, clinical testing will assess its suitability for integration into surgical practice. They along with collaborators developed a soft, wearable electrogoniometry device that provide continuous, wireless tracking of finger and wrist motion, overcoming the limitations of intermittent, subjective clinical goniometry. Using embedded magnetometers in a skin-conforming platform, these sensors enable objective, high-resolution monitoring of joint motion during therapy and daily activity, supporting quantitative biofeedback and improved rehabilitation after hand and wrist surgery.

His research has been funded by the National Institutes of Health (NIH), Barnes Jewish Foundation (BJF), Medtronic, ViOptix, and Canadian Institutes of Health Research (CHIR).

Sack’s focus is advancements in the field of plastic and reconstructive surgery, tissue engineering and biotechnology, and novel vascular repair devices. Clinical interests include the reconstruction of all forms of acquired, oncological, and traumatic defects ranging from the head and neck to the breast, chest, abdomen, pelvis, and extremities. He is also a co-founder of Lifesprout, which developed intellectual property around a novel tissue scaffold currently in a clinical trial, as well as a co-founder of Tissuelock, which is developing a novel internal-use tissue adhesive.

Tevlin’s laboratory is inspired every day by the patients and families they have the privilege to care for. The challenges they face motivate our efforts to better understand how the craniofacial skeleton develops, heals, and regenerates — and how that biology can be harnessed to improve reconstruction.

Her research sits at the intersection of developmental biology, mechanotransduction, skeletal regeneration, and craniofacial surgery. Building on prior work in skeletal stem cell biology and the development of clinically relevant preclinical models of surgical disease, they use single-cell and spatial technologies, advanced imaging, human tissues, and innovative animal models to investigate the cellular and molecular programs that govern craniofacial bone formation and repair.

A major focus of the lab is understanding how the craniofacial skeleton responds to mechanical and surgical perturbation, with particular interests in distraction osteogenesis, craniofacial trauma, and developmental disorders of the skull and face. They are especially interested in translating these insights into new regenerative and reconstructive strategies for complex craniofacial defects.

Ultimately, their goal is to move beyond simply replacing what has been lost — toward biologically informed approaches that restore form, function, and growth.

She is building a collaborative, curious, and welcoming team and always excited to work with students and trainees who share an interest in craniofacial biology, regeneration, and translational research. Her group welcomes new ideas, new perspectives, and collaborations that help ask better questions and ultimately improve the care of patients.

Wood’s focus is investigating the pathology, mechanisms, and treatments for traumatic peripheral nerve injuries. His broad research interest focuses on bioengineering approaches to improve the management of peripheral nerve injuries, especially in the setting of physical trauma. As such, his research is cross-disciplinary, where the focus of studies spans the fields of surgery, neuroscience, and biomedical engineering.

• Understanding the limits to repairing nerve
  One aspect of his research program entails understanding and improving nerve regeneration across environments that are less hospitable to axon growth, such as during nerve regeneration across nerve grafts, or axon regeneration across long distances, involving significant time for regeneration and recovery to occur. In collaboration with Susan Mackinnon, MD, they first identified premature expression of senescence (age-independent) and stress markers in Schwann cells that limit their capabilities to promote regeneration. Additionally, his group identified a critical role for inflammation and leukocytes during regeneration that also modulates regeneration. And more recently, studies are focused on how the structure of blood vessels affects regeneration. Overall, this increased understanding provides therapeutic targets for improving and enhancing regeneration.
• Bioengineering to improve nerve regeneration
  Incorporating bioengineering approaches, he, along with colleague Xiaowei Li, PhD, have been developing biomaterial strategies to provide therapeutics to treat nerve injuries. Currently, their groups are developing a method to use an injectable hydrogel with drug loaded micelles to provide therapeutic payloads to injured nerve to improve the regenerative environment, where we are targeting Schwann cells and immunomodulation. This improved regenerative environment could in turn improve axon regeneration and lead to better functional recovery.
• Collaborations with industry to advance the management of nerve injuries
  His group has ongoing translational research projects that encompass a true “bed to benchside” research approach, often with direct industry collaboration. As an example of a translational research project, his group has worked with device manufacturers to determine efficacy to provide therapeutic benefits. For example, electrical stimulation therapy provided at the time of nerve repair by surgeons can improve the entire process of nerve regeneration by improving angiogenesis, axon outgrowth, axon guidance to end-organ targets, and facilitate functional recovery. Alternatively, neuroma “capping” devices can manage painful conditions when nerve reconstruction with regeneration to restore function is not an option. These efforts translate therapies to improve patient care following nerve injuries.

The Peripheral Nerve Surgical Research Lab (PNSRL) is a consortium of investigators with the shared goal of investigating the pathology mechanisms and treatments for peripheral nerve injuries. 

Matthew Wood, MD, who directs the lab, and Susan Mackinnon, MD, lead a multidisciplinary team that focuses their research on these main goals:

• Translational advances to treating peripheral nerve injuries
• Understanding the limits to repairing nerve gaps
• Developing approaches to repair large gaps

Susan Mackinnon, MD, leads clinical research to advance the management of nerve-injured patients. Working with Andrew Yee, PhD, Mackinnon also is pursuing video-based learning in nerve surgery, not only to include nerve surgeries themselves, but also to include the component of clinical judgment and patient selection, which is critical to patient safety and quality improvement outcomes. Mackinnon and Yee also are using a web-based approach to investigate the utility of coaching surgeons on patient selection criteria and on their surgical techniques.

Research within the Plastic and Reconstructive Surgery Bioengineering Lab focuses on augmenting and improving the surgeon’s capabilities to manage and reconstruct major tissue injuries through developing bioengineered therapies. The basic and translational research conducted in this lab focuses on:

• Bioengineered scaffolds to repair large and long tissue defects
• Therapeutic electrical stimulation protocols to promote regeneration

Xiaowei Li, PhD, develops biomaterials platforms for regenerative medicine, with specific interest in applications of biomaterials for angiogenesis and vascularization, stem cell engineering and tissue regeneration. Li focuses on exploiting bioengineering strategies for tissue regeneration by combining the principles of biomaterial science, biological science, stem cell biology, tissue engineering, regenerative medicine with the advanced techniques in molecular and cell biology, with a goal of developing biomaterial approaches to induce a permissive microenvironment to improve efficiency of stem cell therapies for regeneration of injured/diseased tissues. He also works to apply biomaterial platforms to influence endogenous cell fates to promote functional tissue regeneration.