Knee extensor torque of men with early degrees of osteoarthritis is associated with pain, stiffness and function

Clinical Scenario: Knee pathologies often require rehabilitation to address the loss of knee-extensor (KE) strength, function, and heightened pain. However, in the early stages of rehabilitation, higher loads may be contraindicated. Blood flow restriction (BFR) resistance training does not require high loads and has been used clinically to promote strength improvements in a variety of injured populations. BFR resistance training may be an effective alternative to high-intensity resistance training during early rehabilitation of knee pathologies. Clinical Question: Following a knee injury, does BFR resistance training improve KE strength and function, and reduce patient-reported pain? Summary of Key Findings: Four randomized controlled trial studies met the inclusion criteria. Each included study evaluated the use of BFR resistance training on knee pathologies and the effects on KE strength, functional outcomes, and pain compared with high- or low-load resistance training. All 4 studies reported significant improvements in KE strength, function, and pain through a variety of outcome measures, following BFR resistance training use as the treatment. Clinical Bottom Line: There is consistent evidence to support the use of BFR resistance training as a treatment intervention following knee injury and as a means to improve KE strength and function and to reduce pain. Strength of Recommendation: Grade A evidence supporting the use of BFR resistance training for improvement in KE strength and function, and the reduction of patient-reported pain following an acute or chronic knee pathology.

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Muscle pain from an intramuscular injection of hypertonic saline increases variability in knee extensor torque reproduction

Journal of Applied Physiology ◽

10.1152/japplphysiol.00139.2020 ◽

2020 ◽

Author(s):

Samuel Andrew Smith ◽

Dominic Micklewright ◽

Samantha Lee Winter ◽

Alexis R. Mauger

Keyword(s):

Hypertonic Saline ◽

Muscle Pain ◽

Intramuscular Injection ◽

Vastus Lateralis ◽

Isotonic Saline ◽

Knee Extensor ◽

Knee Extensors ◽

Saline Control ◽

Reproduction Task ◽

Extensor Torque

Purpose: The intensity of exercise-induced pain (EIP) reflects the metabolic environment in the exercising muscle, so during endurance exercise this may inform the intelligent regulation of work rate. Conversely, the acute debilitating effects of EIP on motor unit recruitment could impair the estimation of force produced by the muscle and impair judgement of current exercise intensity. This study investigated whether muscle pain that feels like EIP, administered via intramuscular injection of hypertonic saline, interferes with the ability to accurately reproduce torque in a muscle group relevant to locomotive exercise. Methods: On separate days, fourteen participants completed an isometric torque reproduction task of the knee extensors. Participants were required to produce torque at 15 and 20% maximal voluntary torque (MVIT), without visual feedback before (Baseline), during (Pain/No Pain), and after (Recovery) an injection of 0.9% isotonic saline (Control) or 5.8% hypertonic saline (Experimental) into the vastus lateralis of the right leg. Results: An elevated reported intensity of pain, and a significantly increased variance in mean contraction torque at both 15% (P=0.049) and 20% (P=0.002) MVIT was observed in the Experimental compared to the Control condition. Both 15 and 20% target torques were performed at a similar pain intensity in the Experimental condition (15% MVIT, 4.2 ± 1.9; 20% MVIT, 4.5 ± 2.2; P>0.05). Conclusion: These findings demonstrate that the increased muscle pain from the injection of hypertonic saline impeded accurate reproduction of knee extensor torque. These findings have implications for the detrimental impact of EIP on exercise regulation and endurance performance.

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Knee Extensor Torque Variability Correlates With Impaired Functional Knee Kinetics After ACLR In Collegiate Athletes

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000676232.80192.d2 ◽

2020 ◽

Vol 52 (7S) ◽

pp. 244-244

Author(s):

Tyler J. Roehl ◽

Daniel G. Cobian ◽

Mikel R. Stiffler-Joachim ◽

Jennifer L. Sanfilippo ◽

Bryan C. Heiderscheit

Keyword(s):

Knee Extensor ◽

Collegiate Athletes ◽

Knee Kinetics ◽

Extensor Torque

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Reduced knee-extensor torque steadiness and higher motor unit discharge rate variability in individuals with patellofemoral pain

Physiotherapy ◽

10.1016/j.physio.2018.11.294 ◽

2019 ◽

Vol 105 ◽

pp. e46

Author(s):

E. Martinez-Valdes ◽

G. Boccia ◽

M. Nawaz ◽

F. Negro ◽

A. Rainoldi ◽

...

Keyword(s):

Motor Unit ◽

Discharge Rate ◽

Knee Extensor ◽

Patellofemoral Pain ◽

Unit Discharge ◽

Motor Unit Discharge ◽

Extensor Torque

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Reduced rate of knee extensor torque development in older adults with knee osteoarthritis is associated with intrinsic muscle contractile deficits

Experimental Gerontology ◽

10.1016/j.exger.2015.08.016 ◽

2015 ◽

Vol 72 ◽

pp. 16-21 ◽

Cited By ~ 11

Author(s):

Damien M. Callahan ◽

Timothy W. Tourville ◽

James R. Slauterbeck ◽

Philip A. Ades ◽

Jennifer Stevens-Lapsley ◽

...

Keyword(s):

Older Adults ◽

Knee Osteoarthritis ◽

Knee Extensor ◽

Intrinsic Muscle ◽

Reduced Rate ◽

Extensor Torque ◽

Muscle Contractile ◽

Torque Development

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Agreement of three vs. eight isokinetic preset velocities to determine knee extensor torque- and power-velocity relationships

Isokinetics and Exercise Science ◽

10.3233/ies-130524 ◽

2014 ◽

Vol 22 (1) ◽

pp. 1-7 ◽

Cited By ~ 6

Author(s):

A. Lemaire ◽

M. Ripamonti ◽

M. Ritz ◽

A. Rahmani

Keyword(s):

Knee Extensor ◽

Extensor Torque

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Impaired regulation post-stroke of motor unit firing behavior during volitional relaxation of knee extensor torque assessed using high density surface EMG decomposition

2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) ◽

10.1109/embc.2015.7319420 ◽

2015 ◽

Cited By ~ 5

Author(s):

Spencer A. Murphy ◽

Reivian Berrios ◽

P. Andrew Nelson ◽

Francesco Negro ◽

Dario Farina ◽

...

Keyword(s):

Motor Unit ◽

Knee Extensor ◽

Surface Emg ◽

High Density ◽

Firing Behavior ◽

Post Stroke ◽

Motor Unit Firing ◽

Density Surface ◽

Extensor Torque

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Relationships between maximal strength, muscle size, and myosin heavy chain isoform composition and postactivation potentiation

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2015-0403 ◽

2016 ◽

Vol 41 (5) ◽

pp. 491-497 ◽

Cited By ~ 9

Author(s):

Laurent B. Seitz ◽

Gabriel S. Trajano ◽

G. Gregory Haff ◽

Charles C.L.S. Dumke ◽

James J. Tufano ◽

...

Keyword(s):

Skeletal Muscle ◽

Myosin Heavy Chain ◽

Heavy Chain ◽

Human Skeletal Muscle ◽

Knee Extensor ◽

Type Ii ◽

Postactivation Potentiation ◽

Test Protocol ◽

Extensor Torque ◽

Type Ii Myosin

The purpose of this study was to examine the relationships between maximal voluntary postactivation potentiation (PAP) and maximal knee extensor torque, quadriceps cross-sectional area (CSA) and volume, and type II myosin heavy chain (MHC) isoform percentage in human skeletal muscle. Thirteen resistance-trained men completed a test protocol consisting of 2 isokinetic knee extensions at 180°·s–1 performed before and 1, 4, 7, and 10 min after the completion of 4 maximal knee extensions at 60°·s–1 (i.e., a conditioning activity (CA)). Magnetic resonance imaging and muscle microbiopsy procedures were completed on separate days to assess quadriceps CSA and volume and MHC isoform content. Maximal voluntary PAP response was assessed as the ratio of the highest knee extensor torques measured before and after the CA. There were large to very large correlations between maximal voluntary PAP response and maximal knee extensor torque (r = 0.62) and quadriceps CSA (r = 0.68) and volume (r = 0.63). Nonetheless, these correlations were not statistically significant after adjusting for the influence of type II MHC percentage using partial correlation analysis. By contrast, the strongest correlation was observed for type II MHC percentage (r = 0.77), and this correlation remained significant after adjusting for the other variables. Maximal voluntary PAP response is strongly correlated with maximal knee extensor torque and quadriceps CSA and volume, but is mostly clearly associated with the type II myosin isoform percentage in human skeletal muscle.

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