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Skeletal Muscle Atrophy and Dysfunction Following Total Knee Arthroplasty

Not Applicable
Completed
Conditions
Knee Osteoarthristis
Registration Number
NCT03051984
Lead Sponsor
University of Vermont
Brief Summary

Total knee replacement, or arthroplasty, is the final clinical intervention available to relieve pain and functional limitations related to advanced stage knee osteoarthritis. Despite its beneficial effects, the early post-surgical period is characterized by the erosion of lower extremity muscle size and strength that cause further disability and slow functional recovery. While the detrimental effects of this period on muscle are widely recognized, the mechanisms underlying these adaptations are poorly understood and there are currently no widely-accepted clinical interventions to counter them

Detailed Description

Total knee arthroplasty (TKA) is currently the most common elective surgery in the US and will increase in frequency nearly five-fold by 2030 to 3.5 million surgeries annually. This surgery is most prevalent among older adults with advanced knee osteoarthritis (OA) and its increase is explained primarily by growth in this population. Although TKA reliably reduces joint pain, it fails to correct objectively-measured functional disability due, in part, to dramatic declines in lower-extremity neuromuscular function during the early, postsurgical period. These deficits are never fully remediated, remaining for years after surgery and contributing to persistent disability. Despite these detrimental effects of TKA, the fundamental skeletal muscle adaptations that occur in the early, post-surgical period are poorly defined and understudied and there is currently no widely-accepted, evidence-based intervention to counter these changes. To address this clinical problem, the investigators goals in this application are to define the skeletal muscle structural and functional adaptations following TKA at the whole body, tissue, cellular, organellar and molecular levels in humans in an effort to identify factors contributing to functional disability and to assess the utility of neuromuscular electrical stimulation (NMES) to counter post-surgical muscle adaptations at these same anatomic levels. We hypothesize that TKA fails to remediate physical disability in patients, in part, because of the profound skeletal muscle myofilament and mitochondrial loss and dysfunction that develops during the early, post-surgical period. Moreover, the investigators posit that NMES will improve functional recovery following TKA by countering these early skeletal muscle adaptations. To test this model, the investigators will evaluate participants with knee OA prior to and following TKA for skeletal muscle structure and function at multiple anatomic levels, with patients randomized to receive NMES or sham control intervention during the first 5 weeks post-surgery.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
23
Inclusion Criteria
  • symptomatic, primary knee osteoarthritis (OA)
  • being considered for total knee arthroplasty
Exclusion Criteria
  • knee OA secondary to inflammatory/autoimmune disease
  • untreated/uncontrolled hypertension, diabetes or thyroid disease
  • chronic heart failure, actively-treated malignancy, exercise-limiting peripheral vascular disease, stroke or neuromuscular disease
  • body mass index >38 kg/m2
  • lower extremity blood clot or known coagulopathies
  • implanted pacemaker/ICD

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
Cross-sectional Area (CSA) of Muscle FibersBaseline and 5-weeks post-TKA surgery

CSA of skeletal muscle fibers via myosin heavy chain (MHC) immunohistochemistry

Intermyofibrillar Mitochondrial ContentBaseline and 5-weeks post-TKA surgery

Fractional area of intermyofibrillar (IMF) mitochondria via electron microscopy

Maximal Calcium-activated Tension Single Muscle Fiber TensionBaseline and 5-weeks post-TKA surgery

Tension (force per unit muscle fiber cross-sectional area) from segments of chemically-skinned single human muscle fibers assessed under maximal calcium-activated condition, with muscle fiber type determined post-measurement by gel electrophoresis

Secondary Outcome Measures
NameTimeMethod
Physical Activity LevelBaseline and 5-weeks post-TKA surgery

Physical activity will be assessed by accelerometry.

Quadriceps Muscle Cross-sectional AreaBaseline and 5-weeks post-TKA surgery

Quadriceps muscle cross-sectional area will be assessed by computed tomography at the mid-thigh on both surgical and non-surgical non-surgical legs.

Short Physical Performance BatteryBaseline and 5-weeks post-TKA surgery

Physical functional assessment based on 2 lower extremity activities (5-time sit-to-stand, 4-m gait speed) and standing balance (side-side, tandem, semi-tandem) based on time or repetitions (0-4 score) with a minimum score of 0 and a maximal score of 12. Each activity is scored from 0 to 4 based on the level of performance (with higher values indicating better physical function and lower values indicating increasing levels of disability). The scores from the 3 activities are summed to give the total score, which is what is reported. Higher total score values indicate higher levels of physical function (more healthy), whereas lower values indicate increasing levels of physical disability/frailty.

Knee Extensor Muscle StrengthBaseline and 5-weeks post-TKA surgery

Knee extensor isometric peak torque assessed by dynamometry on the surgical leg.

30-second Sit-to-stand TestAssessed at baseline and 5 weeks post-surgery

Number of repetitions that an individual can complete the sit-to-stand transition in 30 seconds

Trial Locations

Locations (1)

University of Vermont College of Medicine

🇺🇸

Burlington, Vermont, United States

University of Vermont College of Medicine
🇺🇸Burlington, Vermont, United States

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