By Elizabeth Lockwood | Health.mil
Cutting-edge technology that analyzes the intricacies of how a wounded warrior walks is helping some of our nation’s heroes gain better insight into their injuries and how they can optimize their recovery.
The technology, installed in the biomechanics laboratory at Walter Reed Army Medical Center in Washington in 2007, takes the guess work out of analyzing human gait, and allows physicians, physical therapists and prosthetists to work together in creating and adjusting specific prosthetic limbs tailored for each patient.
“It gives [patients] a sense of the flow of their motion without being distracted by any body image issues they may have,” said therapist Barri Schnall, the lab’s program manager. “They’ll say to me, ‘Barri, my therapist has been telling me that I’ve been leaning to one side but now I can really see it.’”
The biomechanics laboratory, previously known as the gait lab, uses a pressure-sensitive floor and a series of infrared cameras to measure torque, force and joint angles in a patient’s core, legs and prostheses.
Schnall explained how the data collected at the lab can determine where a person’s power is being generated, which ultimately influences how a therapist will approach rehabilitation and how a prosthetist will proceed with prosthetic adjustments or changes.
“I’ve seen the biomechanics laboratory help rehabilitative therapy by eliminating the guess work,” Schnall said. “We get objective information on how the prosthetic feet are absorbing and returning energy. We give that information back to the prosthetist, and they can make alignment changes that will immediately affect the patient’s gait pattern.”
How It Works
A patient visit to the biomechanics laboratory begins with a preliminary questionnaire about the patient’s prosthesis issues and rehab expectations. Range of motion exercises follow, which provide therapists a baseline analysis of the patient’s flexibility and strength. This physical evaluation also gives the therapist information about the patient’s skill and comfort with the prosthesis.
The most important part of a patient’s visit is the gait analysis. The floor of the biomechanics laboratory is outfitted with six calibrated force plates, and the walls are hung with 23 infrared cameras. A series of reflective markers placed on the patient’s prominent joints enable the cameras to capture a simple stroll across the room. A computer then renders the collected data into a 3-D stick figure that walks across the lab engineer’s computer screen.
“What’s really interesting is we thought patients would react very favorably to seeing the video of how they are walking, but they react more strongly to the stick figures,” Schnall said.
Seeing Results
“We [all] work together closely as part of the rehab team,” Schnall said of the lab’s care providers. “We share the objective information on how a patient is walking to optimize prosthetic alignment or choose a particular prosthetic device and see if one is working better for a patient than another. We use all of the objective information to be able to help the patient achieve their individual goals.”
These patients – most of them service members who have been wounded in support of Operation Iraqi Freedom or Operation Enduring Freedom – set their goals high. Schnall said she sees many patients who aim to return to active duty.
“The technology is very encouraging,” Schnall said, “It gives them an objective means of knowing how they are stacking up – I know from the service members I’ve treated that they don’t want to return unless they can be what they were before or at least close to it. They don’t want to let their unit down and they wouldn’t put other service members in jeopardy. The biomechanics laboratory gives us and the medical community a way to guide our patients and give them peace of mind in returning to duty.”
But whether or not patients aim to return to active duty, there is no doubt that the biomechanics lab at Walter Reed is one medical technology that is bringing patients closer to their goals – one force-calibrated step at a time.
DoD has additional biomechanics laboratories at Brooke Army Medical Center in San Antonio and Navy Medical Center San Diego.