Effects of treadmill running and limb immobilization on knee cartilage degeneration and locomotor joint kinematics in rats following knee meniscal transection

• Type of Material: Article
• Authors: L.-C. Tsai, Georgia State University; E.S. Cooper, Emory University; K.M. Hetzendorfer, Georgia Institute of Technology; G.L. Warren, Georgia State University; Y.-H. Chang, Georgia Institute of Technology; Nick Willett, Emory University
• Language: English
• Date: 2019-12-01
• Publisher: ELSEVIER SCI LTD
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: 2020
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.joca.2019.08.001
• Title of Journal or Parent Work: OSTEOARTHRITIS AND CARTILAGE
• Volume: 27
• Issue: 12
• Start Page: 1851
• End Page: 1859
• Grant/Funding Information: The authors acknowledge the efforts of Dr. Caroline R. Waters and Dr. Katelyn N. Corbin for their assistance with data acquisition.
• Keywords: MORPHOLOGY; TIBIOFEMORAL COMPRESSIVE FORCES; X-ray motion analysis; Osteoarthritis; PROGRESSION; CHONDROCYTES; Orthopedics; ARTICULAR-CARTILAGE; Computed tomography; Rehabilitation; VARUS THRUST; Science & Technology; Knee injury; OSTEOARTHRITIS; GAIT COMPENSATIONS; Rheumatology; Life Sciences & Biomedicine; 3-DIMENSIONAL MODEL; LIGAMENT
• Research Categories: Biology, Anatomy; Biology, General

Abstract

Objective: This study examined the effects of reduced and elevated weight bearing on post-traumatic osteoarthritis (PTOA) development, locomotor joint kinematics, and degree of voluntary activity in rats following medial meniscal transection (MMT). Design: Twenty-one adult rats were subjected to MMT surgery of the left hindlimb and then assigned to one of three groups: (1) regular (i.e., no intervention), (2) hindlimb immobilization, or (3) treadmill running. Sham surgery was performed in four additional rats. Voluntary wheel run time/distance was measured, and 3D hindlimb kinematics were quantified during treadmill locomotion using biplanar radiography. Rats were euthanized 8 weeks after MMT or sham surgery, and the microstructure of the tibial cartilage and subchondral bone was quantified using contrast enhanced micro-CT. Results: All three MMT groups showed signs of PTOA (full-thickness lesions and/or increased cartilage volume) compared to the sham group, however the regular and treadmill-running groups had greater osteophyte formation than the immobilization group. For the immobilization group, increased volume was only observed in the anterior region of the cartilage. The treadmill-running group demonstrated a greater knee varus angle at mid-stance than the sham group, while the immobilization group demonstrated greater reduction in voluntary running than all the other groups at 2 weeks post-surgery. Conclusions: Elevated weight-bearing via treadmill running at a slow/moderate speed did not accelerate PTOA in MMT rats when compared to regular weight-bearing. Reduced weight-bearing via immobilization may attenuate overall PTOA but still resulted in regional cartilage degeneration. Overall, there were minimal differences in hindlimb kinematics and voluntary running between MMT and sham rats.