Page 64 - REV T-I JOURNAL INTERIOR ISSUU 18 2-3

140 HIGHSMITH ET AL.

INTRODUCTION fied of each subject’s assigned condition via telephone
Compared to non-microprocessor prosthetic knee on the day of the subject’s knee fitting. All fittings
systems (NMPK), the C-Leg microprocessor knee and adjustments were performed by the same study
system (MPK; Otto Bock Healthcare, Duderstadt, prosthetist, who was state-licensed and certified by
Germany) is more efficient in terms of gait bioener- the American Board for Certification in Orthotics,
gentics and health-economic measures as well as safer Prosthetics, and Pedorthics as well as by Ottobock
for persons with transfemoral amputation (TFA) (1). Healthcare for fitting both C-Leg and Genium MPK
Recently, the Genium MPK system has demonstrated systems. Subjects’ prosthetic sockets and suspension
improvements in perceived functional measures systems were not changed for the experiment’s dura-
(2), knee kinematics (3), and physical functional tion to reduce confounding effects from fitting and
performance (4) compared to C-Leg. Clinimetric acclimation issues. Subjects were fit with an Ottob-
assessment and health economic analysis have not yet ock Trias (standard height) or Axtion (low profile)
been conducted. Therefore, the purpose of this study prosthetic foot, based on limb length, for use over
was to determine if laboratory determined benefits the study duration. Manufacturer specifications were
of the Genium are detectable using common clinical used to set componentry alignment and were verified
outcome assessments. A second purpose was to deter- using the LASAR (Ottobock, Duderstadt, Germany)
mine if there are health-economic benefits associated alignment system.
with use of the Genium knee system.
Fitting and Accommodation Periods
METHODS After enrollment, anthropometric and demo-
The study was approved by the University of South graphic data and the study foot were recorded. Knee
Florida’s Institutional Review Board and listed in a fittings and alignment were conducted and settings
federal clinical trial registry. Subjects gave informed recorded. Subjects were invited to return to the study
consent prior to participation in the study. prosthetist or physical therapist for adjustment, align-
Study Design Overview ment, and training as many times as they wished to
optimize fit, comfort, and function and to mirror real
A randomized experimental crossover design, clinical practice and component prescription. Visits
where TFA patients used Genium and C-Leg MPK were counted and reasons for each visit recorded. All
systems, was used. Subjects tested on both knee subjects, regardless of the knee system with which
systems in random order separated by an accommo- they began the study, received an initial training
dation period of >2 weeks to <3 months, depending session from the study physical therapist for each
upon when they determined their readiness to test. knee system for training in transitional movements,
Subjects were assessed in a university clinical labora- obstacle crossing, ramps, stairs, speed variation, and
tory setting using common clinical outcome measures variable surfaces. Portions of the study’s training tech-
as described below.
niques have been previously published (5,6).
Randomization, Eligibility, and Interventions The minimum accommodation period was two
Subjects had to be unilateral TFA patients from weeks. After this, subjects were contacted weekly
any etiology and not have impairments that adversely to determine their ability to walk without personal
impacted their gait beyond their amputations (e.g., assistance on 1) level ground, 2) inclines, 3) declines,
cardiopulmonary, orthopedic impairments). Addi- 4) up & down stairs, and 5) on uneven ground. Sub-
tionally, subjects had to be C-Leg users for ≥1 year jects could contact investigators at any time after
prior to enrollment. An electronic random number the two-week minimum to declare their readiness
generator was used to assign subjects (off site) to to physically demonstrate they had accommodated
either continue with the C-Leg or be fit with a Genium to their currently assigned knee and study foot. Sub-
MPK at recruitment. The study prosthetist was noti- jects were considered accommodated after verbally