EUKINES Wearable Plantar-Pressure Insole System for Rehabilitation After Total Hip Arthroplasty (EUKINES)

Prospective, Randomized, Partially Blinded, Multicenter Non-Inferiority Trial of the EUKINES Wearable Plantar-Pressure Insole Gait-Analysis System for Postoperative Rehabilitation After Primary Total Hip Arthroplasty

This study evaluates a wearable plantar-pressure insole system (EUKINES) designed to support gait training during postoperative rehabilitation after primary total hip arthroplasty (THA). The trial will include 200 adults who are randomly assigned to one of four rehabilitation programs: EUKINES with real-time biofeedback, EUKINES without biofeedback, a certified commercial reference system with biofeedback, or standard rehabilitation without any gait-analysis device. All participants will receive a structured 6-week rehabilitation program after THA, and the only differences between groups concern the use of gait-analysis technology and biofeedback. The main outcomes include changes in plantar-pressure-based gait parameters (mean foot pressure and load asymmetry) and standard clinical scores of hip function and symptoms. The study will also monitor safety, device-related events, walking speed, pain, and patient and therapist ratings of usability and satisfaction. The goal is to determine whether rehabilitation supported by the EUKINES insole system is at least as effective and safe as rehabilitation supported by a certified reference system and as standard care, and to explore the feasibility of using low-cost, printed-sensor technology for routine gait assessment and future telerehabilitation.

Study Overview

• Status: Completed
• Conditions: Hip Osteoarthritis; Total Hip Arthroplasty (THA); Postoperative Rehabilitation
• Intervention / Treatment: Device: EUKINES plantar-pressure insole system; Other: Structured postoperative rehabilitation program; Device: Certified reference gait-analysis system

Detailed Description

This is a prospective, randomized, partially blinded, multicenter clinical trial with a non-inferiority design conducted in patients undergoing primary total hip arthroplasty (THA) for advanced osteoarthritis. The study is embedded in the EUKINES project, which develops low-cost, printable pressure sensors and a wearable plantar-pressure insole system intended for scalable clinical rehabilitation and telerehabilitation use. The trial evaluates the clinical performance, safety, and usability of the EUKINES insole system as an adjunct to standard postoperative rehabilitation.

Adult patients scheduled for primary THA will be screened according to predefined inclusion and exclusion criteria and enrolled after providing written informed consent. A total of 200 participants will be randomized in blocks to one of four parallel rehabilitation arms: (1) EUKINES with real-time biofeedback, (2) EUKINES without biofeedback (data recording only), (3) a certified commercial reference gait-analysis system with biofeedback, or (4) standard rehabilitation without any gait-analysis device. All participants will follow the same structured 6-week rehabilitation program after surgery, including routine physiotherapy and six additional, approximately 3-hour gait-focused sessions. The content and duration of rehabilitation are equivalent across groups; only the use of gait-analysis devices and biofeedback differs between arms.

Outcome assessments will be performed at baseline and during postoperative follow-up. Primary endpoints include changes in plantar-pressure-derived gait parameters such as mean foot pressure and load asymmetry between the operated and non-operated limb, as well as changes in hip-related clinical scores (Harris Hip Score and the 12-item Hip Disability and Osteoarthritis Outcome Score, HOOS-12) and the incidence of adverse events and device-related complications. Secondary outcomes include extended spatiotemporal gait parameters, 10-Meter Walk Test performance, pain intensity and satisfaction with surgery and rehabilitation, and patient and therapist ratings of usability, comfort, and perceived usefulness of the EUKINES and reference systems. All plantar-pressure time-series data will be stored to allow post-hoc derivation of additional gait metrics and exploratory analyses.

The study is classified as a low-risk, add-on interventional trial that does not alter standard surgical procedures or baseline postoperative care. Device-assisted rehabilitation sessions are provided as an adjunct to routine practice. The trial is conducted in accordance with the Declaration of Helsinki and Good Clinical Practice, under the oversight of a bioethics committee. By directly comparing the EUKINES prototype with a certified commercial reference system and standard care, the study aims to demonstrate the feasibility and clinical usefulness of an affordable sensor-based gait-analysis platform and to provide a basis for future development of data-driven telerehabilitation and personalized rehabilitation strategies.

• Study Type: Interventional
• Enrollment (Actual): 200
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Poland
  • Masovian Voivodeship
    • Warsaw, Masovian Voivodeship, Poland, 01-938
      • Cardinal Stefan Wyszynski University in Warsaw, Collegium Medicum - Affiliated Orthopaedic Department

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18 years or older.
• Scheduled for primary total hip arthroplasty performed for advanced osteoarthritis or other degenerative hip disease.
• Willingness and ability to participate in the 6-week postoperative rehabilitation program and follow-up assessments.
• Ability to understand study information and provide written informed consent.

Exclusion Criteria:

• Coexisting medical conditions that may significantly affect rehabilitation outcomes or gait (e.g., severe neurological disorders, major lower-limb joint trauma, other significant musculoskeletal pathology).
• Cognitive impairment or psychiatric conditions that would preclude effective cooperation with the rehabilitation and research team.
• Any contraindication to participation in additional gait training sessions or use of the insole-based gait-analysis systems as judged by the treating physician.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: EUKINES with biofeedback; Participants receive the structured postoperative rehabilitation program supported by the EUKINES plantar-pressure insole system with real-time biofeedback on gait parameters during the additional rehabilitation sessions.	Device: EUKINES plantar-pressure insole system; Wearable plantar-pressure insole system developed within the EUKINES project, consisting of thin-film printed pressure sensors, shoe-mounted electronic modules, and PC-based software for real-time gait data acquisition and visualization. In the biofeedback arm, real-time feedback on gait parameters is provided during rehabilitation sessions; in the non-biofeedback arm, data are recorded without feedback.; Other: Structured postoperative rehabilitation program; Standard postoperative rehabilitation program after total hip arthroplasty, delivered according to local clinical protocols and including six additional approximately 3-hour gait-focused rehabilitation sessions over 6 weeks, with progressive gait training, balance and coordination exercises, and functional mobility tasks.
Experimental: EUKINES without biofeedback; Participants receive the structured postoperative rehabilitation program while wearing the EUKINES plantar-pressure insole system without real-time biofeedback; gait data are recorded for analysis only during the additional rehabilitation sessions.	Device: EUKINES plantar-pressure insole system; Wearable plantar-pressure insole system developed within the EUKINES project, consisting of thin-film printed pressure sensors, shoe-mounted electronic modules, and PC-based software for real-time gait data acquisition and visualization. In the biofeedback arm, real-time feedback on gait parameters is provided during rehabilitation sessions; in the non-biofeedback arm, data are recorded without feedback.; Other: Structured postoperative rehabilitation program; Standard postoperative rehabilitation program after total hip arthroplasty, delivered according to local clinical protocols and including six additional approximately 3-hour gait-focused rehabilitation sessions over 6 weeks, with progressive gait training, balance and coordination exercises, and functional mobility tasks.
Active Comparator: Reference system with biofeedback; Participants receive the structured postoperative rehabilitation program supported by a certified commercial plantar-pressure gait-analysis system providing real-time biofeedback on gait parameters during the additional rehabilitation sessions.	Other: Structured postoperative rehabilitation program; Standard postoperative rehabilitation program after total hip arthroplasty, delivered according to local clinical protocols and including six additional approximately 3-hour gait-focused rehabilitation sessions over 6 weeks, with progressive gait training, balance and coordination exercises, and functional mobility tasks.; Device: Certified reference gait-analysis system; Commercially available, certified plantar-pressure gait-analysis system used according to the manufacturer's recommendations to provide real-time biofeedback on gait parameters during rehabilitation sessions.
Active Comparator: Standard rehabilitation; Participants receive the same structured postoperative rehabilitation program without any gait-analysis device or biofeedback; rehabilitation is based on standard clinical practice at participating centers.	Other: Structured postoperative rehabilitation program; Standard postoperative rehabilitation program after total hip arthroplasty, delivered according to local clinical protocols and including six additional approximately 3-hour gait-focused rehabilitation sessions over 6 weeks, with progressive gait training, balance and coordination exercises, and functional mobility tasks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in mean foot pressure (MFP) on the operated limb	Mean foot pressure (MFP) is defined as the average plantar pressure across all active sensing regions of the insole during the stance phase of gait, expressed in kilopascals. MFP will be recorded during standardized 10-meter walking trials using the EUKINES and/or reference insole systems, and session-level MFP will be calculated as the mean value across all valid steps. The primary analysis will compare changes in MFP on the operated limb over time and between rehabilitation arms.	Baseline (Week 0), Week 3, Week 6 after surgery
Change in load asymmetry between operated and non-operated limb	Load asymmetry will be quantified using plantar-pressure data from the EUKINES and/or reference insole systems as the difference or ratio between mean foot pressure on the operated and non-operated limb during standardized 10-meter walking trials. Reduced inter-limb asymmetry over time will be interpreted as improved functional load distribution after total hip arthroplasty.	Baseline (Week 0), Week 3, Week 6 after surgery
Change in Harris Hip Score (HHS)	The Harris Hip Score is a validated clinician-administered scale assessing pain, function, range of motion, and absence of deformity in patients after hip surgery. Total scores range from 0 to 100, with higher scores indicating better hip function. The primary analysis will compare changes in HHS from baseline to Week 6 between rehabilitation arms.	Baseline (preoperative or immediate postoperative) and Week 6 after surgery
Change in HOOS-12 total score	The HOOS-12 is a validated 12-item short form of the Hip Disability and Osteoarthritis Outcome Score that assesses pain, function, and quality of life in hip patients. Scores are transformed to a 0-100 scale, with higher scores indicating better outcomes. The main analysis will evaluate changes in HOOS-12 total score from baseline to Week 6, with reference to the minimal clinically important difference of approximately 9-12 points reported in the literature.	Baseline (preoperative or immediate postoperative) and Week 6 after surgery
Incidence of adverse events and device-related complications	Safety will be assessed by recording all adverse events, device-related complications, skin irritation, falls, or other medical incidents potentially associated with device use or the supplementary rehabilitation sessions. Events will be classified by severity, relationship to the device or intervention, and outcome.	From enrollment through Week 6 after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Preferred walking speed (10-Meter Walk Test)	Preferred walking speed over 10 meters will be measured in m/s during standardized 10-Meter Walk Tests; changes over time and between groups will be analyzed.	Baseline, Week 3, Week 6
Change in maximal walking speed (10-Meter Walk Test)	Maximal walking speed over 10 meters will be measured in m/s during standardized 10-Meter Walk Tests; changes over time and between groups will be analyzed.	Baseline, Week 3, Week 6
Change in spatiotemporal gait parameters derived from plantar-pressure insoles	Baseline, Week 3, Week 6	Additional gait parameters (e.g., cadence, stance and swing phase duration, rollover time) will be derived from plantar-pressure time-series data and analyzed as exploratory secondary outcomes.
Change in hip pain intensity (VAS)	Hip pain will be rated on a visual analogue scale (0-10), with higher scores indicating greater pain; changes over time and between groups will be compared.	Baseline, Week 3, Week 6
Change in patient satisfaction with surgery and rehabilitation measured with a Visual Analogue Scale (VAS)	Patient satisfaction with surgery and postoperative rehabilitation will be assessed using a 100-mm Visual Analogue Scale (VAS) ranging from 0 to 100, where 0 indicates "not satisfied at all" (worst possible satisfaction) and 100 indicates "extremely satisfied" (best possible satisfaction). The VAS score (points, 0-100; higher scores indicate better satisfaction) will be recorded at Week 3 and Week 6 after surgery, and changes over time and between study groups will be compared	Week 3 and Week 6
Patient-reported usability and comfort of the EUKINES and reference systems (study-specific 15-item Likert-scale questionnaire)	Patient-reported usability and comfort of the EUKINES system and the reference system will be assessed with a study-specific EUKINES Usability and Comfort Questionnaire developed by the investigators, consisting of 15 items rated on a 5-point Likert scale (0 = strongly disagree, 4 = strongly agree). For each system, an overall usability and comfort score will be calculated as the mean of all item scores and expressed in points (range 0-4; higher scores indicate better usability and greater comfort). Scores will be collected at Week 3 and Week 6 after surgery, and changes over time and between study groups will be compared.	Week 3 and Week 6
Therapist-reported usability and perceived usefulness of the EUKINES and reference systems (study-specific 12-item Likert-scale questionnaire)	Therapist-reported usability and perceived usefulness of the EUKINES system and the reference system will be assessed with a study-specific EUKINES Therapist Usability and Usefulness Questionnaire developed by the investigators, consisting of 12 items rated on a 5-point Likert scale (0 = strongly disagree, 4 = strongly agree). Two summary scores will be calculated for each system: a usability score and a perceived usefulness score, each expressed in points as the mean of the corresponding items (range 0-4; higher scores indicate better usability or greater perceived usefulness). Scores collected throughout the 6-week rehabilitation period will be analyzed as repeated measures and compared between systems and between study groups.	Throughout the 6-week rehabilitation period

Collaborators and Investigators

• Sponsor: Cardinal Stefan Wyszynski University
• Collaborators: Warsaw University of Technology; National Center for Research and Development, Poland
• Investigators: Principal Investigator: Andrzej Kotela, Cardinal Stefan Wyszynski University in Warsaw

Study record dates

Study Major Dates

• Study Start (Actual): December 15, 2024
• Primary Completion (Actual): November 30, 2025
• Study Completion (Actual): November 30, 2025

Study Registration Dates

• First Submitted: February 11, 2026
• First Submitted That Met QC Criteria: March 1, 2026
• First Posted (Actual): March 4, 2026

Study Record Updates

• Last Update Posted (Actual): March 4, 2026
• Last Update Submitted That Met QC Criteria: March 1, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: biofeedback; rehabilitation; total hip arthroplasty; gait analysis; telerehabilitation; wearable sensors; plantar-pressure insoles; printed sensors; mean foot pressure; EUKINES
• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Osteoarthritis; Osteoarthritis, Hip
• Other Study ID Numbers: UKSW/EUKINES-THA-01; TECHMATSTRATEG-III-0032-2019 (Other Grant/Funding Number: National Centre for Research and Development (NCBR))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared because there is no dedicated infrastructure or funding for long-term controlled access data sharing beyond the requirements for publication and regulatory reporting.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No