Technology & Innovation 15(4) Abstracts

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Technology and Innovation, Vol. 15, pp. 287-292
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488878899
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

The Effect of the Walkaide Functional Electrical Stimulation Unit on Gait Asymmetry in a Child With Cerebral Palsy: A Case Report

Michael K. Carroll,* Chris A. Toelle,† Seok Hun Kim,‡ Steven B. Ambler,‡§ and M. Jason Highsmith‡¶

*Hanger Clinic, Oklahoma City, OK, USA
†Hanger Clinic, Sarasota, FL, USA
‡School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
§Physical Therapy Center, University of South Florida, Tampa, FL, USA
¶Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA

Numerous orthotic interventions such as ankle–foot orthoses (AFOs) are prescribed for children with cerebral palsy (CP) to address goals from contracture management to improved mobility. Recently, alternative orthotic management incorporating functional electrical stimulation (FES) has been prescribed for children with CP to further improve walking quality and ambulatory function. This case report describes the application of bilaterally fitted WalkAide (WA) FES systems on a 12-year-old child with spastic diplegic CP with lifelong rehabilitation experience for the management of contractures, walking dysfunction, safety issues, and other physical impairments. The subject’s walking ability was assessed with a four square step test (FSST), 2-minute walk test (2MWT), and the GAITRite Walkway. The level of assist and spatiotemporal gait factors were also measured. Outcomes were measured first in the subject’s thermoplastic solid ankle AFOs and then again following 2 weeks of acclimation with the WA devices. No statistically significant differences in spatiotemporal gait parameters, FSST, and 2MWT were found between the two interventions. However, clinically observable improvements in walking speed, FSST, and 2MWT were noted when using the WAs. Therapeutic benefits of the WAs in children with CP may include improved walking speed, multidirectional stepping, and walking endurance. These outcomes may be of particular benefit considering play and activities of daily living for children. Further studies with a greater number of subjects are needed to generalize results.

Key words: Ankle–foot orthoses (AFOs); Gait; Spastic diplegia; Functional electrical stimulation (FES)

Accepted April 2, 2013.

Address correspondence to Michael K. Carroll, CPO, Hanger Clinic, 4301 N. Classen Boulevard, Oklahoma City, OK 73118, USA. Tel: +1-405-525-4000; Fax: +1-405-530-3670; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 293-296
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488878934
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

On the Design of Manually Ad justable Ankle Units for Variable Terrain: A Technical Note

Derek J. Lura*† and M. Jason Highsmith‡§

*Department of Mechanical Engineering, University of South Florida, Tampa, FL, USA
†Center for Assistive, Rehabilitation and Robotics Technologies,
University of South Florida, Tampa, FL, USA
‡School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
§Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA

This article provides details on the design of adjustable ankle units for transfemoral and transtibial prosthetic devices. The design was intended to enable the user to quickly adjust the flexion of a prosthetic foot in subfreezing temperatures, where donning and doffing clothing and the prosthesis present a significant obstacle. The units must also be able to tolerate significant abuse, cold, ice, and water while maintaining their function. Additionally, the units must be attached using standard pylons or fittings and must be short enough to fit in the existing pylon space so no modification to the user’s socket or prosthetic foot is required. This article presents two potential solutions to the proposed problem, one with continuous adjustment using a friction fitting and one with discrete positioning using a geared coupling. A finite element analysis of the design was performed to determine the suitability of the design material and dimensions. The proposed friction fitting was found to have greater potential, but benefits of other methods are discussed as well. Future work will focus on failure testing of prototype devices, followed by in-use field testing by highly active amputee subjects.

Key words: Ankle prosthesis; Academic invention; Mountaineering

Accepted April 2, 2013.
Address correspondence to Derek J. Lura, Ph.D., Center for Assistive, Rehabilitation and Robotics Technologies, University of South Florida, 4202 E. Fowler Ave, ENB 118, Tampa, FL 33620, USA. Tel: +1-813-974-9651; Fax: +1-813-974-3539; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 297-300
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488878970
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Design and Performance of a Push-Up Device for Above-Elbow Amputees: A Technical Note

Matthew M. Wernke,*† Derek J. Lura,*† Stephanie L. Carey,*† and M. Jason Highsmith‡§

*Department of Mechanical Engineering, University of South Florida, Tampa, FL, USA
†Center for Assistive, Rehabilitation, and Robotics Technologies, University of South Florida, Tampa, FL, USA
‡School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
§Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA

This article provides details on the design and performance of a push-up device for above-elbow amputees. The push-up performance of a transhumeral amputee using a push-up device was compared with that of a nonamputee control participant performing a regular push-up. The push-up device was designed by the amputee participant. After analyzing the data and obtaining permission from the amputee participant, the authors redesigned the push-up device based on the following criteria: easy to construct with common tools, made from common materials, lightweight (less than 10 lb), adjustable, durable, smaller than the original device, could be operated with one hand, and inexpensive (less than $50). This technical note details the current design of the push-up device and expected performance to provide a means by which an individual with an above-elbow limb amputation can engage in regular exercise.

Key words: Above elbow; Amputee; Exercise; Push-up

Accepted April 2, 2013.
Address correspondence to Matthew Wernke, BSBME, Center for Assistive, Rehabilitation, and Robotics Technologies, University of South Florida, 4202 E. Fowler Ave, ENB 118, Tampa, FL 33620, USA. Tel: +1-813-974-9651; Fax: +1-813-974-3539; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 301-309
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DOI: http://dx.doi.org/10.3727/194982413X13844488879014
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Current Concepts Regarding Externally Powered Lower Limb Prostheses

Phillip M. Stevens

Hanger Clinic, Salt Lake City, UT, USA

Historically, prosthetic solutions for the lower extremities have been confined to passive ankle/foot and knee devices. These components have demonstrated the ability to restore some, but not all, of the functional losses associated with lower limb amputation. The human ankle generally generates more work than it absorbs during both level-ground ambulation and during ascension tasks. The human knee absorbs net energy during level-ground ambulation but must generate net energy during ascension tasks. The inability of modern passive prosthetic mechanisms to replicate the energy demands of the lower limb has created a need for externally powered devices. At the ankle, design strategies have included pneumatic systems and battery-powered systems. In the case of the latter, efficiencies have been bolstered by coupling elastic springs with powered drive mechanisms capable of augmenting either the load or strain upon the springs to increase the energy released during gait. Several design strategies have demonstrated an ability to replicate the work requirements at the ankle, with additional suggestions of reduced energy consumption and increased self-selected walking speeds. The value of powered prosthetic knees may occur during ascension tasks, with early literature suggesting a decreased reliance on the sound side limb during transfers and step-over-step stair ascent. An emerging design is intentionally energy neutral during level walking, with the ability to generate positive work as needed during tasks of ascension. A single design strategy for a combination of ankle/knee prosthesis has been developed and reported upon in the form of cases studies.

Key words: Lower limb amputation; Lower limb prostheses; Powered prosthesis

Accepted April 2, 2013.
Address correspondence to Phil Stevens, 5292 S. College Dr. #103, Salt Lake City, UT 84123, USA. Tel: +1-801-266-7768; Fax: +1-801-266-9570; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 311-315
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488879050
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Transtibial Amputee Energy Expenditure During Vertical Ice Climbing and Snowshoeing

M. Jason Highsmith,*† Jason T. Kahle,* Derek J. Lura,‡ and Larry J. Mengelkoch§

*School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
‡Department of Mechanical Engineering, University of South Florida, Tampa, FL, USA
§University of St. Augustine for Health Sciences, St. Augustine, FL, USA

Beyond running, little is known about energy expenditure measurements during adventure-type activities for persons with lower extremity amputation. The purpose of this study was to determine energy expenditure for a transtibial amputee (TTA) during a prolonged snowshoeing trek and a vertical ice climb. The subject, a unilateral TTA using a multifunction prosthesis, participated in an arctic wilderness survival training course in Denali, Alaska. While training, heart rate (HR) measurements were recorded continuously during a 1-h snowshoeing trek to a vertical ice climb site. To determine how field activities compare to peak energy expenditure, the subject participated in a laboratory-based, maximal effort exercise test. Metabolic data were collected using the COSMED K4b2 system to determine peak oxygen uptake (VO2) and HR and actual values of HR at any given %VO2 peak. During maximal exercise, VO2 peak = 38.4 ± 1.73 ml*kg−1*min−1 and HR peak = 188 ± 0 beats*min−1. During the 60-min snowshoeing trek, relative energy expenditure ranged from ≈21.1 to 30.7 ml*kg−1*min−1 = 55% to 80% VO2 peak. During the 24-min, 18.3-m vertical ice climb, relative energy expenditure ranged from approximately 22.1 to 31.5 ml*kg−1*min−1 = 58% to 81% VO2 peak. The relative energy expenditure levels for these activities were performed at moderate to vigorous intensity. Energy expenditure was similar to current metabolic equivalent (MET) data reported for nonamputee subjects during moderate to vigorous intensity snowshoeing activities. This study further demonstrates that some persons with TTA may be capable of performing adventure-type activities at relative energy expenditure levels similar to nonamputee subjects.

Key words: Amputation; Metabolics; Mountaineering; Oxygen uptake (VO2); Physical therapy; Rehabilitation

Accepted April 8, 2013.
Address Correspondence to M. Jason Highsmith, University of South Florida, School of Physical Therapy and Rehabilitation Sciences, 12901 Bruce B. Downs Blvd. MDC077, Tampa, FL 33612, USA. Tel: +1-813-974-3806; Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 317-324
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488879096
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Energy Consumption, Ambulatory Prognosis, and Individualized Technical Solutions for Persons With Bilateral Transfemoral Amputations: A Literature Review

Amanda L. Lewandowski,* Daniel W. Bodkin,† Stephen A. Noe,‡ John J. Orriola,§ John W. Michael,¶ Jason T. Kahle,# and M. Jason Highsmith#**

*Select Physical Therapy, Brandon, FL, USA
†Pro-Active Physical Therapy, Tampa, FL, USA
‡Halcyon Rehabilitation, Tampa, FL, USA
§Shimberg Health Sciences Library, University of South Florida, Tampa, FL, USA
¶Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL, USA
#School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
**Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA

There are over 350,000 persons in the US living with transfemoral amputation. Within this group are a number of individuals living with bilateral transfemoral amputation (BTFA). Literature on this group of individuals is sparse. The purpose of this review was to determine if commonly held views regarding BTFA function and ambulatory prognosis are supported by the literature. Specifically, we were interested in identifying how different the bioenergetics of walking are between BTFAs and other levels of amputation as well as nonamputees. Additionally, we were interested in learning what novel technical solutions had been reported and what ambulatory prognostic statements were available that might guide the rehabilitation process of this unique population. Four databases were searched systematically, resulting in the review of 19 articles. Available literature supports the long-held notion that ambulatory energy requirements associated with BTFA are high and that wheelchair adoption for mobility is common for many in this group, particularly those with advanced age and considerable comorbidity. Novel technical solutions have been reported that increased independence for specific individuals.

Key words: Above-knee amputee; Assistive device; Physical therapy; Prosthesis; Rehabilitation; Wheelchair

Accepted April 10, 2013.
Address correspondence to Amanda Lewandowski, Select Physical Therapy, 2410 Brandon Blvd, Brandon, FL 33511, USA. Tel: +1-813-654-0686; Fax: +1-813-685-2241; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 325-332
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DOI: http://dx.doi.org/10.3727/194982413X13844488879131
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Locomotor Training on a Treadmill Compared With PNF Training in Adults With Chronic Stroke

Jeannie B. Stephenson,* Murray E. Maitland,† Jason W. Beckstead,‡ and Wendy K. Anemaet§

*School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Division of Physical Therapy, University of Washington, Seattle, WA, USA
‡College of Nursing, University of South Florida, Tampa, FL, USA
§School of Physical Therapy, Regis University, Denver, CO, USA

Persons with stroke often have decreased gait velocity and gait deviations. Many interventions are employed to remediate these impairments; however, more evidence is needed to determine which interventions are superior. This randomized controlled trial looked at the effects of body weight-supported treadmill training (BWSTT) compared with proprioceptive neuromuscular facilitation (PNF). Eighteen subjects with chronic (>6 months) stroke were randomized into one of three groups: BWSTT, PNF, or control. All subjects received pre- and posttesting on the 10-m walk test, cadence, and the Wisconsin Gait Scale (WGS). The control group received no interventions. The PNF group received mat activities and gait training for 30 min three times a week for 4 weeks. The BWSTT group received locomotor training on a treadmill with body weight support for 20 min three times a week for 4 weeks. A significant difference from pretest to posttest (p ≤ 0.05) for both gait velocity and cadence was found for BWSTT and PNF groups using a two-way analysis of variance (ANOVA) test and Tukey post hoc analysis with treatment groups showing greater improvement than the control group. Similarly, a Kruskal–Wallis test revealed significant between-group differences (p ≤ 0.05) on WGS. Post hoc analysis with Mann–Whitney U test found a significantly better improvement (p ≤ 0.05) in both treatment groups compared to control with the PNF group showing greatest improvement. These preliminary results support the efficacy of both BWSTT and PNF training (compared with no training) to improve gait in people with stroke.

Key words: Gait training; Locomotor training; Body weight supported treadmill training; Gait velocity; Proprioceptive neuromuscular facilitation; Stroke rehabilitation

Accepted May 1, 2013.
Address correspondence to Jeannie B. Stephenson, PT, MS, NCS, School of Physical Therapy and Rehabilitation Sciences, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Blvd., MDC 77, Tampa, FL 33612-4766, USA. Tel: +1-813-974-5523; Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 333-341
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488879177
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

The Effects of Vacuum-Assisted Suspension on Residual Limb Physiology, Wound Healing, and Function: A Systematic Review

Jason T. Kahle,*† John J. Orriola,‡ Will Johnston,§ and M. Jason Highsmith*¶

*School of Physical Therapy & Rehabilitation, University of South Florida, Tampa, FL, USA
†Prosthetic Design + Research, Tampa, FL, USA
‡Shimberg Health Sciences Library, University of South Florida, Tampa, FL, USA
§College of Public Health, University of South Florida, Tampa, FL, USA
¶Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA

This literature review was undertaken to determine if commonly held views about the benefits of vacuum-assisted suspension (VAS) are supported by the literature. Following screening, full-text articles were reviewed and sorted by reviewers into the following relevant topics: residual limb physiology, wound healing, and function. A total of 35 articles were identified as potential articles. After screening, eight articles were identified as pertinent. Two articles included methodology that was applied to separate topics. Five articles were sorted into the “residual limb physiology” topic, two articles into the “wound healing” topic, and three articles into the “function” topic. There is evidence supporting the clinical outcomes of VAS for the prosthetic user when considering residual limb physiology. There is limited evidence supporting the clinical outcomes when considering wound healing and function. The mechanical principles of VAS applied to prosthetic use may have physiological and functional merit. Applying the associated principles to prosthetic design may create alternative interface design configurations for both the amputee and the prosthetist.

Key words: Transtibial; Transfemoral; Socket; Interface; Subatmospheric

Accepted June 26, 2013.
Address correspondence to Jason T. Kahle, M.S.M.S., C.P.O., F.A.A.O.P., School of Physical Therapy & Rehabilitation, University of South Florida, 3515 E. Fletcher Avenue, MDC77, Tampa, FL 33612, USA. Tel: +1-813-416-3419; Fax: +1-813-971-9300; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 343-347
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DOI: http://dx.doi.org/10.3727/194982413X13844488879212
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

The Effect of the C-Leg Knee Prosthesis on Sensory Dependency and Falls During Sensory Organization Testing

M. Jason Highsmith,*† Jason T. Kahle,* Neil T. Shepard,‡ and Kenton R. Kaufman§

*School of Physical Therapy & Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
‡Department of Otorhinolaryngology, Mayo Clinic, Rochester, MN, USA
§Department of Orthopaedics, Mayo Clinic, Rochester, MN, USA

A mechanistic explanation for previously observed safety improvements with microprocessor-controlled prosthetic knees is needed. A repeated measures design of 15 subjects with unilateral transfemoral amputation was used to assess changes between baseline use of their standard of care, mechanical prostheses, and a C-Leg microprocessor-controlled prosthetic knee. The primary outcome measures were sensory dependency scores for somatosensory, visual, vestibular, and visual preference, which were calculated based on a Sensory Organization Test. Falls during posturographic assessment were also recorded. Somatosensory system dependency significantly increased (p = 0.047) while using the C-Leg compared to a nonmicroprocessor prosthetic knee (NMPK). Reliance on visual with vestibular input and reliance on vestibular input alone were not significantly increased with C-Leg use (p = 0.41 and p = 0.15, respectively). When utilizing the C-Leg, there was a significant reduction in the average number of falls (p = 0.03). Hence, increased reliance on somatosensory input is a possible explanation for improved balance with use of a microprocessor prosthetic knee (MPK).

Key words: Amputee; Balance; NeuroCom; Rehabilitation; Safety; Transfemoral

Accepted October 21, 2013.
Address correspondence to M. Jason Highsmith, University of South Florida, Morsani College of Medicine, School of Physical Therapy & Rehabilitation Sciences, 12901 Bruce B. Downs Blvd. MDC 077, Tampa, FL 33612-4799, USA. Tel: +1-813-974-3806 (office); Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 349-358
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488879267
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Stair Ascent and Ramp Gait Training With the Genium Knee

M. Jason Highsmith,*† Jason T. Kahle,*‡ Derek J. Lura,§ Amanda L. Lewandowski,¶ William S. Quillen,*† and Seok Hun Kim*

*School of Physical Therapy & Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
‡Prosthetic Research and Design, Tampa, FL, USA
§Whitaker College of Engineering, Department of Bioengineering and Software Engineering, Florida Gulf Coast University, Fort Myers, FL, USA
¶Select Physical Therapy, Brandon, FL, USA

Patients with transfemoral amputation who ambulate in the community will likely encounter stairs and ramps. Previous microprocessor knee systems have focused on enabling reciprocal stair descent. Recently, the Genium knee has included functions to enable reciprocal stair climbing and improve gait when negotiating ramps and ambulating on grades. The techniques used to train patients to utilize these features are described. Many of the patients who were trained were able to climb stairs reciprocally with the Genium knee. On ramps, two walking patterns emerged that seemed somewhat dependent upon the ramp slope or grade. One of these patterns was observationally characteristic of nonamputee gait; however, biomechanical studies are ongoing.

Key words: Amputee; Physical therapy; Prosthesis; Rehabilitation; Slope; Transfemoral

Accepted May 1, 2013.
Address correspondence to M. Jason Highsmith, School of Physical Therapy & Rehabilitation Sciences, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 077, Tampa, FL 33612-4799, USA. Tel: +1-813-974-3806 (office); Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 359-368
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844488879302
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Short and Mid-Distance Walking and Posturography With a Novel Microprocessor Knee

M. Jason Highsmith,*† Jason T. Kahle,* Derek J. Lura,‡ Rajiv V. Dubey,‡ Stephanie L. Carey,‡ William S. Quillen,*† and Larry J. Mengelkoch§

*School of Physical Therapy & Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
‡Mechanical Engineering Department, University of South Florida, Tampa, FL, USA
§University of St. Augustine for Health Sciences, St. Augustine, FL, USA

The purpose of this project was to determine if walking speed increases and if ambulatory-related exertion decreases in transfemoral amputees (TFAs) using the novel Genium microprocessor knee. A second purpose was to determine if directional and postural control improves with the Genium knee. Gait speed increases in TFAs were not observed in preliminary analyses. However, gait biomechanical improvements such as swing phase knee flexion angle consistency were reported. Such improvements may be perceptible to the user in short and mid-distance walking tests. Significant differences were observed between TFAs and controls for walking test times, but no differences were found between knee systems. A trend of decreased perceived exertion was observed with Genium compared with C-Leg, but differences did not reach significance. Controls consistently rated greater exertion during walking, possibly as a result of walking faster. TFAs show considerable impairment compared to controls in directional control, and the Genium tends to improve rearward-directed control. The C-Leg significantly improves control over the prosthetic forefoot. Postural control was not different between the two knee systems. During short to medium distances, the Genium sustains walking speed improvements realized by the C-Leg but at potentially decreased levels of perceived exertion. However, C-Leg use results in improved anterolateral directional control compared with Genium, likely due to its toe load requirement. Conversely, Genium use tended to improve control in rearward directions.

Key words: Balance; C-Leg; Genium knee; Prosthesis; Transfemoral amputee (TFA); Timed walking tes

Accepted June 26, 2013.
Address correspondence to M. Jason Highsmith, School of Physical Therapy & Rehabilitation Sciences, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 077, Tampa, FL 33612-4799, USA. Tel: +1-813-974-3806 (office); Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 15, pp. 369-375
1929-8241/14 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982413X13844489091297
E-ISSN 1949-825X
Copyright © 2014 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Perceived Differences Between the Genium and the C-Leg Microprocessor Prosthetic Knees in Prosthetic-Related Function and Quality of Life

M. Jason Highsmith,*† Jason T. Kahle,* Rebecca M. Miro,*† Derek J. Lura,‡ Rajiv V. Dubey,§ Stephanie L. Carey,§ William S. Quillen,*† and Larry J. Mengelkoch¶

*School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa, FL, USA
†Center for Neuromusculoskeletal Research, University of South Florida, Tampa, FL, USA
‡Department of Bioengineering and Software Engineering, Florida Gulf Coast University, Fort Myers, FL, USA
§Department of Mechanical Engineering, University of South Florida, Tampa, FL, USA
¶University of St. Augustine for Health Sciences, St. Augustine, FL, USA

Microprocessor knees (MPKs) are a viable option for persons with transfemoral amputation (TFA). Studies have assessed biomechanics and physical function to quantify MPK functional performance. However, it is also essential to assess patient perception as part of evidence-based practice using valid and reliable measures. The Prosthesis Evaluation Questionnaire (PEQ) evaluates prosthetic-related function and quality of life. The PEQ has been used in MPK literature to compare perceptive response between C-Leg and non-microprocessor-controlled knee mechanisms. The Genium, a new MPK, has not been assessed for differences in perceived function. The purpose of this project was to report perceived differences in prosthetic function and quality of life following accommodation with a Genium compared with a C-Leg. Twenty people with TFA participated in this randomized crossover study. C-Leg users randomized to test first with their own C-Leg or a Genium then crossed over into the other condition for repeated testing. Nonknee prosthetic attributes were held constant. Participants completed the PEQ for each knee condition to compare perceived differences in prosthetic function and quality of life. Genium use resulted in significant improvements (p ≤ 0.05) in the following scales — Perceived Response, Social Burden, Utility, and Well-Being — as well as in individual items related to improved standing comfort, satisfaction with walking ability, and improved gait in tight spaces, hills, and slippery surfaces (p < 0.025). As a result of using the Genium, patients perceive improvements in prosthetic-related quality of life and function. Further, patients perceive improvements in very specific mobility functions related to ambulation on complex settings.

Key words: Prosthesis Evaluation Questionnaire (PEQ); Rehabilitation; Subjective analysis; Survey; Transfemoral amputee (TFA)

Accepted October 24, 2013.
Address correspondence to M. Jason Highsmith, School of Physical Therapy & Rehabilitation Sciences, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 077, Tampa, FL 33612-4799, USA. Tel: +1-813-974-3806 (office); Fax: +1-813-974-8915; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it