Photography by Gregg Goldman

​Ben Hingst becomes emotional as he vividly remembers the day he saw his son, Noah, run down the hall at the doctor’s office.

Noah Hingst with his mom and dad, Heather and Ben, and his sister, Lilah

“I felt joy,” he says. “Just pure joy, and thankfulness for all the doctors and to God for healing our son so he could walk again.”

Noah was just 6 years old when he walked up behind someone mowing the lawn who didn’t know he was there. In an instant, as the lawnmower was backed up, Noah’s foot was caught underneath it, sharp blades cutting through skin, muscle and bone in his foot and toes. “They told us at the hospital that his foot might have to be amputated,” says Hingst. “We were in total shock.”

But after talking with an orthopedic team that was determined to work to save Noah’s foot, the family agreed to a complicated limb reconstruction process that involved multiple surgeries to clean out the wound, re-attach severed toes, transplant a portion of Noah’s back muscle and skin over the foot to cover the wound, and reconnect blood vessels to restore blood flow.

The result? “I have video of Noah running in my clinic just two and a half months after the last surgery,” says David Brogan, MD, MSc, Washington University orthopedic surgeon at Barnes-Jewish Hospital. Brogan specializes in boney and microvascular limb reconstruction. “It’s now been four years, and Noah’s recovered so well he’s running cross country for his school.”

Collaborative care

Across the country, and at Barnes-Jewish Hospital and Washington University School of Medicine, collaborative, multidisciplinary teams are working to preserve and reconstruct damaged limbs. Such teams include specialists from multiple fields: orthopedics, trauma, acute and critical care, plastic and reconstructive surgery, vascular surgery, podiatry, wound care and rehabilitation, all working together to lower the number of amputations performed each year.

It’s a huge issue. In the U.S. alone, more than 185,000 amputations are performed annually. According to the Amputee Coalition of America, 2 million people in the United States currently live with limb loss, a statistic expected to double by 2050. Though many may imagine the causes for amputation to be linked to traumatic injuries like Noah’s, the reality is that far more than half of all amputations are the result of peripheral vascular disease and complications from diseases such as diabetes.

Orthopedic reconstruction

The Washington University orthopedic team averages 120 limb reconstruction procedures annually. The people they treat are most often at risk of losing a limb due to a traumatic injury or cancer.

Christopher McAndrew, MD, Washington University orthopedic trauma specialist at Barnes-Jewish Hospital, oversees bone stabilization and reconstruction, and works with orthopedic microvascular surgeons Brogan and Martin Boyer, MD, who specialize in soft tissue reconstruction, and Christopher Dy, MD, who focuses on nerve repair. “For the people we treat, speed is essential,” explains Brogan. “We get an injury cleaned, get it stabilized and get it covered. The longer you wait, the higher the risk for infection. And if you can’t clear the infection, the risk for limb loss goes up.”

The work of reconstructing—or salvaging—a limb is not new, but advanced options for bone fixation (using rods, screws, pins, plates and other stabilizers) coupled with advances in microvascular surgery for the repair of soft tissue and nerve injury have dramatically improved outcomes for patients. Success—the preservation of a damaged limb—depends on ensuring that good blood supply continually flows into the damaged area, which keeps alive the tissue grafts that are placed to cover a wound. Successful preservation also means that injured nerves can be repaired to help restore sensation and movement.

Diabetes and limb preservation

Dave Kordenbrock and podiatrist Michael Weiss, DPM, discuss his recovery.

Dave Kordenbrock was diagnosed with severe peripheral vascular disease and an amputation of his right leg. But thanks to a collaborative effort involving Plastic and Reconstructive Surgery, Vascular Surgery, Acute Care and Critical Surgery, specialists were able to prevent a below-the-knee amputation in his left leg. Kordenbrock now uses an orthotic device to protect his foot and undergoes regular examinations to avoid further complications.

A critical health issue, diabetes significantly affects amputation rates. Poorly controlled blood sugar levels can result in peripheral neuropathy and limited blood flow to legs and toes. Lack of good circulation can lead to a cascading series of problems, including deep foot ulcers that can damage not only soft tissue but also tendons and bones. Infections can then develop in bones (osteomyelitis) or the skin (cellulitis) and spread to other areas of the body.

According to the American Diabetes Association, 85% of all amputations in the U.S. are the direct result of complications from a diabetic foot ulcer. The more quickly such a wound is treated, the lower the risk of amputation, but it takes a multi-pronged effort to restore blood flow, repair an open wound and stop what are called necrotizing infections that result in the death of skin and soft tissue. Given the increasing number of patients needing treatment for diabetes and peripheral vascular disease, Washington University surgeons working at Barnes-Jewish Hospital have made limb preservation a designated area of emphasis, coordinating patient care with specialists working in acute and critical care surgery, plastic surgery and vascular surgery.

Clean, evaluate, cover

Preserving a limb starts with making sure a wound or injury is cleaned thoroughly, with all debris and dead or infected tissue removed. This procedure, called debridement, is critical to reduce the risk for further infection and to help healthy tissue recover. It can be done with or without surgery, depending upon the severity of the wound.

Treatment also includes close inspection of blood flow to determine whether limb preservation will be successful. Wounds need oxygen to heal properly. If there is insufficient or no blood flow to the affected area, any attempt to repair soft tissue damage will fail.

To evaluate blood flow, a physician uses a catheter to inject dye into the area and monitors its flow through veins and arteries. To repair these veins, surgical bypass procedures were the standard of care 20 years ago. In these procedures, surgeons create alternative blood vessels that offer a detour around a blockage. Today, minimally invasive catheter-based interventions, which remove blockages and insert stents to keep the blood vessels open, are more common. “We still do surgical bypass procedures in some situations,” says Patrick Geraghty, MD, Washington University vascular surgeon at Barnes-Jewish Hospital and co-director of the Limb Preservation Program in the Department of Surgery. “But with advancements in catheter-based procedures, we can work within an inch of the toes and in the smaller, micro blood vessels to open and restore blood flow. Typically, we insert a catheter into the groin and work down, but there are times when we have to go from the bottom of the foot up into the leg.”

Metal stents, however, can’t be used in the foot, as they can be crushed during walking. Instead, specialists use tiny guide wires to help remove blockages in the toes’ smaller blood vessels. Geraghty notes that research is under way to evaluate the use of microscopic magnetic beads or nanoparticles that can be guided through blocked vessels to clear the path and restore blood flow. Hyperbaric oxygen therapy, another option currently available, is a noninvasive outpatient procedure that increases the level of oxygen carried in the blood and enhances healing.

“By improving oxygen flow into skin and soft tissue, we actually stimulate new blood vessel growth in the wound area,” says John Kirby, MD, Washington University acute and critical care surgeon at Barnes-Jewish Hospital. “That, in turn, improves the odds of healing, as do procedures to remove dead and infected tissue as quickly as possible.”

There is, however, a delicate balance between ensuring blood flow and working to replace dead or damaged tissue to cover a wound. “I can’t reconstruct a soft tissue cover over a wound without blood flow, and vascular surgeons can’t restore blood flow if there’s a large wound or infection,” says plastic surgeon John Felder, MD, co-director of the Limb Preservation Program. “That’s why it takes such a coordinated effort among specialists to try and save a limb.”

Covering a significant wound is more than placing a patch of skin over a hole. Skin grafts can’t be placed directly onto bone, and skin will die without blood vessels that deliver blood and oxygen. To make an effective repair, microvascular surgeons, including Felder and his counterparts in orthopedic surgery, create a graft using a piece of skin with muscle, arteries and veins still intact, carefully reconnecting it to the remaining blood vessels surrounding a wound. These complex tissue grafts, called flaps, can come from several locations on a patient’s body, including from other areas of a leg or foot (or arm, for an upper-extremity injury), the groin, abdomen or back. Sometimes, surgeons can rotate a skin flap from an adjacent area onto the wound. More common are “free” flap procedures involving a portion of skin and blood vessels from another part of the body that is transplanted to the wounded area. Motor and sensory nerves also can be part of the tissue flap.

“It can take up to four hours or even longer to perform one of these microvascular procedures, but it offers a patient an option other than amputation, which has life-long consequences,” says Felder. “That’s why limb preservation should be considered.”

Brogan agrees. “The reality is that limb reconstruction and preservation can require multiple procedures, but the process can be successful,” he says. “Significantly, it requires extensive follow-up to ensure the flap is viable over the long term.”

The five days following flap surgery represent the greatest period of risk. During this time, infections can develop, and small blood clots can block the flow of blood into the transplanted tissue, causing it to die. To help mitigate these risks, Brogan and Boyer currently are studying a way to better monitor the health of the flaps in the first few days after transplantation. “We are using iPhones equipped with thermal cameras to examine blood perfusion and see if we can detect temperature changes in the flap, which can be indicative of a potential problem with blood flow,” explains Boyer. “Early data is promising. This could be an easy, cost-effective way to monitor the viability of flaps.”

Other research efforts at Washington University School of Medicine are focused on enhancing microvascular techniques and improving tissue perfusion to increase oxygen levels and blood flow. Research projects in the pipeline include work aimed at improving nerve regeneration outcomes and at visualization of nerves during surgical reconstruction. In addition, collaborative research among various specialties is advancing the use of more effective anti-coagulants to further decrease the risk of blood clots.

Rehabilitation

Surgeons now are working more broadly to ensure successful limb reconstruction and preservation outcomes. On the front end of peripheral vascular disease and diabetes, they are advocating for comprehensive programs and monitoring to ensure that patients with diabetes and vascular disease don’t have an initial or recurrent infection or wound that could lead to amputation. Even after limb preservation, underlying medical issues can cause additional problems. “A majority of the people who lose a limb due to vascular or diabetic disease run the risk of additional amputation surgeries on the same or other lower limb if the underlying disease is not addressed,” says Prateek Grover, MD, PhD, MHA, Washington University physical medicine and rehabilitation specialist.

Grover, also medical director of the Rehabilitation Institute of St. Louis, the rehabilitation partner with BJC HealthCare, is leading the development of a coordinated rehabilitation and follow-up program aimed at promoting independent and safe function for people with limb loss due to traumatic injury and vascular disease. He is joined by podiatrists and wound-care specialists working in the Division of Acute and Critical Care Surgery to facilitate comprehensive limb care, including appropriate orthotic selection and wound-healing techniques that can help prevent further limb loss. Grover works with a patient to craft a rehabilitation program based on personal goals that will help ensure the best possible quality of life and mobility.

“Surgery and limb preservation are the beginning of the journey,” Grover says. “The care we provide is a full continuum that includes therapists, orthotists and prosthetists, all working together to help people minimize fall risk and learn to move safely. We are all involved in improving lives while minimizing future complications.”

As limb reconstruction and preservation programs mature, success will be determined by optimal healing, reduced readmission rates and degree of quality of life, both short- and long-term. Already, the teams at Barnes-Jewish Hospital have a more than 99% success rate in flap surgery outcomes due to microvascular expertise and aggressive patient follow-up. This summer, a new joint microsurgery fellowship program, overseen by Boyer in orthopedics and Justin Sacks, MD, MBA, chief of the Division of Plastic and Reconstructive Surgery, will bring the teams closer together to train the next generation of microvascular specialists. “Collaboration—multiple specialties working together for reconstruction and preservation of limbs at risk—is at the heart of what makes Barnes-Jewish Hospital and Washington University School of Medicine such incredible institutions,” says Sacks. “In 2021, multidisciplinary teams working across specialties and sharing expertise will optimize care, and patients will benefit from this enhanced collaboration.”

“We have a population that is growing older,” Kirby notes, “and growing more obese, more sedentary, more diabetic, and those issues come with a higher incidence and severity of peripheral vascular diseases, which can result in more complex and severe lower-extremity wounds.”

Sacks adds: “It’s a major public health problem. If a susceptible patient needs a significant tissue resection or amputation due to peripheral vascular disease, his or her mortality rate rises. We’ve made major progress in the field of cancer care, and we need to do the same as we address the root causes of most amputations. We can’t eliminate all amputations, but with a systematic, coordinated effort, we can lower the number.”