Paraspinal NMES and Spinopelvic Alignment After Knee Arthroplasty
Effect of Paraspinal Neuromuscular Electrical Stimulation Added to Rehabilitation Program on Spinopelvic Alignment Parameters After Total Knee Arthroplasty: A Prospective Randomized Controlled Trial
1 other identifier
interventional
80
1 country
1
Brief Summary
Total knee arthroplasty (TKA) is a widely performed surgical procedure for patients with severe knee osteoarthritis. Following TKA, changes in lower extremity alignment and gait mechanics may influence the spinopelvic sagittal alignment, and postoperative rehabilitation programs traditionally focus on the knee joint without addressing the lumbopelvic chain. This study aims to investigate whether adding paraspinal neuromuscular electrical stimulation (NMES) to a standard postoperative rehabilitation program (which includes quadriceps NMES) affects spinopelvic sagittal alignment parameters in patients undergoing TKA for primary knee osteoarthritis, compared with standard rehabilitation and quadriceps NMES alone. In this single-center, prospective, randomized, single-blind (outcome assessor-blinded) controlled trial, eligible participants aged 40-80 years with primary knee osteoarthritis scheduled for TKA and with measurable spinopelvic malalignment will be randomly assigned in a 1:1 ratio to receive either standard rehabilitation with quadriceps NMES plus paraspinal NMES (intervention group) or standard rehabilitation with quadriceps NMES alone (control group) for 4 weeks (20 sessions). The primary outcome is the change in radiographic spinopelvic parameters - including pelvic tilt, sacral slope, pelvic incidence, lumbar lordosis, sagittal vertical axis, and spinosacral angle - measured on standing lateral whole-spine radiographs at baseline (preoperative), before rehabilitation, after the 4-week intervention, and at 6-month follow-up. Secondary outcomes include knee and back pain (VAS), functional and quality-of-life measures (WOMAC, Knee Society Score, Forgotten Joint Score, Oswestry Disability Index, Nottingham Health Profile), performance-based tests (Timed Up and Go, 6-Minute Walk Test), and knee range of motion. The investigators hypothesize that adding paraspinal NMES to standard rehabilitation will result in greater improvement in spinopelvic alignment parameters, and potentially in clinical/functional outcomes, compared with standard rehabilitation alone.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for not_applicable knee-osteoarthritis
Started Jul 2026
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 23, 2026
CompletedStudy Start
First participant enrolled
July 30, 2026
CompletedFirst Posted
Study publicly available on registry
August 3, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
July 30, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
July 30, 2027
August 3, 2026
July 1, 2026
1 year
July 23, 2026
July 27, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (3)
Change from Baseline in Pelvic Tilt (PT)
Pelvic tilt will be measured as the angle between the line connecting the midpoint of the sacral plate to the center of the femoral head axis and the vertical line, assessed on standing lateral whole-spine radiographs (36-inch cassette) by two independent physicians blinded to group allocation. Measurements will be performed using PACS-integrated measurement software. Interobserver reliability (ICC ≥ 0.85) and intraobserver reliability (repeat measurement at 2-week interval) will be assessed. Unit of Measure: degrees
Baseline (preoperative, T0), before rehabilitation (postoperative, T1), end of 4-week intervention (postoperative week 6, T2), and 6-month follow-up (T4)
Change from Baseline in Sagittal Vertical Axis (SVA)
The horizontal distance between the C7 plumb line and the posterosuperior corner of S1 will be measured on standing lateral whole-spine radiographs. Unit of Measure: millimeters
Baseline (T0), before rehabilitation (T1), end of 4-week intervention (T2), and 6-month follow-up (T4)
Change from Baseline in Radiographic Spinopelvic Angular Parameters (Sacral Slope, Lumbar Lordosis, Spinosacral Angle)
Sacral slope (angle between the S1 superior endplate and horizontal), lumbar lordosis (Cobb angle between L1 and S1), and spinosacral angle (angle between the line connecting the C7 center to the sacral plate midpoint and the sacral plate) will be measured on the same standing lateral whole-spine radiographs described above. Unit of Measure: degrees
Baseline (T0), before rehabilitation (T1), end of 4-week intervention (T2), and 6-month follow-up (T4)
Secondary Outcomes (9)
Change from Baseline in Knee Pain (Visual Analog Scale)
Baseline (preoperative, T0), before rehabilitation (postoperative, T1), end of 4-week intervention (postoperative week 6, T2), postoperative month 3 (T3), and 6-month follow-up (T4)
Change from Baseline in Low Back Pain (Visual Analog Scale)
Baseline (preoperative, T0), before rehabilitation (postoperative, T1), end of 4-week intervention (postoperative week 6, T2), postoperative month 3 (T3), and 6-month follow-up (T4)
Change from Baseline in WOMAC Osteoarthritis Index Score
Baseline (preoperative, T0), end of 4-week intervention (postoperative week 6, T2), postoperative month 3 (T3), and 6-month follow-up (T4)
Change from Baseline in Knee Society Score (KSS)
Baseline (preoperative, T0), before rehabilitation (postoperative, T1), end of 4-week intervention (postoperative week 6, T2), postoperative month 3 (T3), and 6-month follow-up (T4)
Change from Baseline in Forgotten Joint Score (FJS)
Baseline (preoperative, T0), before rehabilitation (postoperative, T1), end of 4-week intervention (postoperative week 6, T2), postoperative month 3 (T3), and 6-month follow-up (T4)
- +4 more secondary outcomes
Study Arms (2)
Experimental: Intervention Group
EXPERIMENTALStandard Rehabilitasyon + Quadriceps NMES + Paraspinal NMES Description: Participants in this arm will receive the standard postoperative rehabilitation program combined with quadriceps NMES, plus additional paraspinal (erector spinae and multifidus) NMES applied bilaterally over the L4-L5 region for 20 minutes/day, 5 days/week, for 4 weeks.
Active Comparator: Control Group
ACTIVE COMPARATORStandard Rehabilitasyon + Quadriceps NMES Description: Participants in this arm will receive the same standard postoperative rehabilitation program combined with quadriceps NMES (bilateral VMO and rectus femoris electrode placement) for 20 minutes/day, 5 days/week, for 4 weeks, without paraspinal NMES.
Interventions
A structured rehabilitation program including early postoperative mobilization (days 1-3: standing, short-distance ambulation, quadriceps isometric exercises, ankle pumping, breathing exercises, cold application), pre-rehabilitation phase (days 4-15: assisted ambulation, straight leg raise, passive range-of-motion exercises), and active rehabilitation phase (weeks 2-3: active-assisted knee ROM exercises, closed kinetic chain exercises, balance training, stair and gait training), along with pain and edema control throughout.
Surface NMES applied bilaterally over the vastus medialis obliquus and rectus femoris muscles (long-sitting position, knee at 30° flexion). Parameters: 50 Hz frequency, 300-400 µs pulse width, duty cycle 1:3 (10 sec on-30 sec off), intensity titrated to patient tolerance to produce visible muscle contraction, 20 minutes/session, once daily, 5 days/week, for 4 weeks.
Surface NMES applied bilaterally to the lumbar paraspinal muscles (erector spinae and multifidus) via 4 hydrogel electrodes placed bilaterally around the L4-L5 spinous processes, in prone position. Parameters: 50 Hz frequency, 250-350 µs pulse width, duty cycle 1:3 (10 sec on-30 sec off), intensity titrated to patient tolerance to produce visible muscle contraction, 20 minutes/session, once daily, 5 days/week, for 4 weeks.
Eligibility Criteria
You may qualify if:
- Age between 40 and 80 years
- Diagnosis of primary knee osteoarthritis scheduled for total knee arthroplasty
- Radiographic evidence of Kellgren-Lawrence grade 3-4 knee osteoarthritis
- Preoperative knee flexion contracture ≥ 5°
- Measurable spinopelvic malalignment, defined as meeting at least one of the following criteria: pelvic tilt (PT) \> 20°, sagittal vertical axis (SVA) \> 50 mm, or lumbar lordosis (LL) \< 40°
- IIntact cognitive function based on clinical judgment, sufficient to understand and follow verbal commands, cooperate with the rehabilitation program, and reliably comply with functional assessment procedures
- Provision of written informed consent
- Able to stand independently and undergo standing lateral radiography
You may not qualify if:
- Prior lumbar or thoracic spinal surgery
- History of hip arthroplasty
- Prior knee arthroplasty (revision arthroplasty patients)
- Active inflammatory arthritis (e.g., rheumatoid arthritis, psoriatic arthritis)
- Neurological disease, including stroke, Parkinson's disease, peripheral neuropathy, or spinal cord pathology
- Contraindications to NMES, including active cardiac pacemaker, implanted defibrillator, deep vein thrombosis, skin integrity impairment, malignancy, or epilepsy
- Severe hip osteoarthritis or other lower extremity pathology significantly affecting spinopelvic alignment (e.g., leg length discrepancy, developmental hip dysplasia, contracture)
- Inability to complete the standard rehabilitation protocol due to postoperative complications
- Osteoporotic vertebral fracture or significant osteoporosis (T-score \< -2.5 at L1-L4)
- Active treatment for malignancy
- Psychiatric or medical condition that would prevent completion of the follow-up period
- General contraindications to exercise
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
University of Health Sciences, Bursa Yuksek Ihtisas Training and Research Hospital
Bursa, Turkey (Türkiye)
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- INVESTIGATOR, OUTCOMES ASSESSOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER GOV
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Principle investigator
Study Record Dates
First Submitted
July 23, 2026
First Posted
August 3, 2026
Study Start
July 30, 2026
Primary Completion (Estimated)
July 30, 2027
Study Completion (Estimated)
July 30, 2027
Last Updated
August 3, 2026
Record last verified: 2026-07
Data Sharing
- IPD Sharing
- Will not share