Evidence map›Paper›PMID 40676418›Full record

ArticleAnnals of biomedical engineering2025

Relative Contributions of Motor Unit Firing Pattern, Muscle Quantity, and Muscle Quality to Maximum Muscle Strength in Female Patients with Early and Severe Knee Osteoarthritis.

Takaya Watabe, Yuichi Nishikawa, Hisashi Naito, Takuya Sengoku, Yuta Taniguchi

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Article in Annals of biomedical engineering, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers, 1 of them a synthesis that pooled it.

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2citing papers in PubMed, 1 pooled it
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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 synthesis or guideline pooled it.

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Takaya WatabeSection of Rehabilitation, Kanazawa University Hospital, 13-1 Takaramachi, Kanazawa, Ishikawa, 920-8641, Japan.ORCID http://orcid.org/0009-0002-4122-3457
Yuichi NishikawaFaculty of Frontier Engineering, Institute of Science and Engineering, Kanazawa University, Kakuma-Machi, Kanazawa, 920-1192, Japan. yuichi@se.kanazawa-u.ac.jp.ORCID http://orcid.org/0000-0002-0088-8447
Hisashi NaitoFaculty of Frontier Engineering, Institute of Science and Engineering, Kanazawa University, Kakuma-Machi, Kanazawa, 920-1192, Japan.ORCID http://orcid.org/0000-0001-9593-1331
Takuya SengokuSection of Rehabilitation, Kanazawa University Hospital, 13-1 Takaramachi, Kanazawa, Ishikawa, 920-8641, Japan.ORCID http://orcid.org/0000-0003-1762-4621
Yuta TaniguchiDepartment of Orthopedic Surgery, Graduate School of Medicine Sciences, Kanazawa University, 13-1 Takaramachi, Kanazawa, Ishikawa, 920-8641, Japan.ORCID http://orcid.org/0000-0002-4322-6566

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeWhile changes in muscle quality and quantity are common concerns as knee osteoarthritis (KOA) progresses, it is equally important to consider the central nervous system's role in regulating muscle force output. This study aimed to elucidate the firing properties of motor units (MUs), muscle quantity, and muscle quality during submaximal isometric contractions in patients with early and severe KOA.

methodsThis was a prospective study comparing 30 patients with KOA according to the Kellgren/Lawrence grading system divided into early and severe KOA groups. The participants performed ramp-up and sustained contractions at 10%, 30%, and 60% of their maximal voluntary contraction (MVC). High-density surface electromyography signals were recorded in the vastus medialis (VM) and vastus lateralis (VL) muscles on the affected side. Skeletal muscle quantity and quality were assessed using computed tomography based on cross-sectional area (CSA) and computed tomography attenuation value (CTV), respectively.

resultsThe CSA of the VM muscle was significantly smaller in the severe KOA group than in the early KOA group (p = 0.021). A total of 682 MUs were detected (early KOA, n = 348, severe KOA, n = 334). The ramp-down phase of the discharge rate (DR) of MUs recruited by the VL muscle in the severe KOA group was significantly lower than that in the early KOA group (p = 0.004). In addition, the knee extension torque of patients with early KOA was significantly correlated with the CSA of the VM muscle (r = 0.405) and the DR obtained at 30% MVC of the VM (r = 0.503) and VL (r = 0.610) muscle. Furthermore, the knee extension torque in patients with severe KOA was significantly correlated with the CTV of the VM (r = 0.677) and VL (r = 0.599) muscles.

conclusionsIn patients with severe KOA, a small CSA of the VM is associated with a characteristic DR pattern depending on the contraction level. The VM and VL muscles fired without a hierarchical pattern in the early and severe KOA groups. These findings suggest that neuromuscular degeneration may occur not only in patients with severe KOA but also in patients with early KOA.

Indexed as

Isometric ContractionMotor NeuronsMuscle, SkeletalMuscle StrengthOsteoarthritis, KneeQuadriceps MuscleAgedElectromyographyFemaleHumansMiddle AgedProspective StudiesElectromyographyKnee osteoarthritisMotor unit recruitmentMuscle qualityMuscle quantity

Identifiers

PMID40676418
PMCPMC12457495

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.