Amputation of Lower Limb Below Knee, Unilateral
Conditions
Keywords
lower limb amputation, somatosensory feedback, functional balance, gait performance, rehabilitation, four square step test
Brief summary
Prosthetics research has grown recently, focusing on bionic approaches that restore bodily functions with technical aids. One method involves using prostheses with feedback systems, which measure physical parameters and provide additional information to the user. Saphenus has developed a feedback system called Suralis© that transfers pressure signals from the prosthetic sole to another body region. This clinical investigation aimed to determine if this system improves gait stability and walking. The study analyzed changes in gait and functional balance and gathered patient-reported measures to evaluate the quality of life. This research was open to individuals who have undergone below-knee amputation but no targeted re-innervation surgery and use prosthetics. Participants received the Suralis© feedback system, and the investigators assessed their walking activities. The system measures prosthetic foot sole pressure and converts it into digital signals, triggering vibration stimuli during the stance phase of walking. The investigators collected gait analyses and patient feedback to assess the impact of the feedback system on prosthetic management. The results will help us understand the benefits and effectiveness of this technology for people with amputation.
Detailed description
The investigators conducted a prospective, unblinded crossover trial to compare the effectiveness of a vibration intervention with no intervention. Participants were randomly assigned to one of two sequences: vibration intervention followed by no intervention or vice versa. The intervention involved using the Suralis© vibrotactile ground-contact feedback system for 60 days. The system transmitted ground contact information to the residual lateral thigh, providing sensory feedback. During the control phase, participants received no additional intervention. The washout period lasted seven days. The study collected data during four visits, assessing gait and patient-reported measures. Bayesian generalized linear mixed models were used for data analysis, considering fixed effects (intervention, sequence, and period) and random effects (individuality).
Interventions
DEVICEvibrotactile ground-contact feedback
Suralis®, Saphenus Medical Technology (Baden, Lower Austria, Austria)
Sponsors
Saphenus Medical Technology GmbH
Ludwig Boltzmann Institute for Traumatology - The research center in cooperation with AUVA
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* male, female, and diverse individuals * unilateral transtibial amputation * at least 18 months post surgery * walking without aids possible * signed informed consent form
Exclusion criteria
* insufficient thigh sensation to distinguish between the two closest vibrotactile actuators * an acute event that restricts the walking ability * interfering lesions or painful conditions * undergone targeted re-innervation surgery * poor stump condition * used a non-modular prosthesis * used a prosthesis in poor condition * conditions preventing safe participation or interfering with study objectives * not able to not comply with the protocol
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Affected leg stance time treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); three tries each assessment day | Stance time of the prosthetic leg during walking over level ground and on a 518 cm instrumented walkway at a self-selected speed |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Unaffected leg step length treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); three tries each assessment day | Step length of the non-prosthetic leg during walking over level ground and on a 518 cm instrumented walkway at a self-selected speed |
| Quality of life score treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); once each assessment day | EuroQol (EQ) 5-Dimension (5D) 3-Level (3L) version, visual analog scale (VAS) |
| Adverse effects frequency treatment difference | Difference in the event frequency during the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V - C; once each assessment day | Patient diary documentation and interview regarding adverse effects |
| Gait speed treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); three tries each assessment day | Average speed of walking over level ground and on a 518 cm instrumented walkway at a self-selected speed |
| 2 min walk test distance treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); once each assessment day | Walking distance in meters within a 2 min time frame |
| Four square step test time treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); three tries each assessment day | Do and reverse four steps over 90 cm long canes arranged in a cross configuration on the ground |
| Timed up and go test time treatment-change difference | Difference between the within-period changes of the 60-day control (C) and vibration (V) periods of the randomized controlled crossover trial, i.e., V(post - pre) - C(post - pre); three tries each assessment day | Stand up, walk 3 m, turn around, and sit down |
Countries
Austria
Outcome results
None listed