This study was funded by Guangzhou Medical University (Grant Number 2018A053).

The clinical project was approved by the Medical Ethics Association of the Fifth Affiliated Hospital of Guangzhou Medical University and has been registered at the China Clinical Trial Registration Center (No. ChiCTR1800017677 and entitled &#8220;Effect and Mechanism of Anti-gravity Treadmill on Lower Limb Motor Function in Patients with Knee Osteoarthritis&#8221;).
1. Recruitment
<ol>
	<li>Recruit patients presenting with radiographic evidence of mild-to-moderate (Kellgren &#38; Lawrence grades II or III) knee OA in one or both knees and knee pain when walking, squatting, and/or kneeling (the minimum level 3/10 on numerical pain rating scale [NPRS] before inclusion).</li>
	<li>Ensure that these patients have no severe knee OA (Kellgren &#38; Lawrence grade IV), retropatellar arthritis or any medical condition that would prevent them from tolerating progressive training.</li>
	<li>Obtain written informed consent from each patient before their participation.</li>
</ol>
2. Pre-training evaluation
<ol>
	<li>Complete demographic forms of the patient including weight, height, past medical history and any past or current medications.</li>
	<li>Clinical assessment
	<ol>
		<li>Conduct the numerical rating scale (NRS)14. Ask the patient to describe the pain intensity with 11 numbers from 0 to 10, where 0 is no pain and 10 is the worst pain.</li>
		<li>Conduct the active/passive knee joint range-of-motion (ROM) assessment15 using a handheld 2-arm goniometer (26-cm arms with 2&#176; markings).</li>
		<li>Conduct the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)16. Ask the patient to mark the corresponding position of pain or limited function on a straight line for 5 pain-related items, 2 stiffness items, and 17 functional items. &#8220;0&#8221; indicates no pain or no function limitation. &#8220;10&#8221; indicates severe pain or extreme limited function.</li>
		<li>Conduct the Knee Injury and Osteoarthritis Outcome Score (KOOS)17 (optional). Ask the patient to finish the self-evaluation questionnaire with five-level for each item in five subscales: pain, other symptoms, activities of daily living, sports, and recreation.</li>
		<li>Conduct the European five-dimensional health scale (EQ-5D)18 (optional). Ask the patient to mark the three-level for five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression.</li>
		<li>Conduct the 10-meter walk test (10 MWT)19. Ask the patient to perform three consecutive 10 MWT trials at a self-selected pace for safety and comfort. Ask the patient to walk without assistance for 10 m and measure the time taken for the middle 6 m (to exclude acceleration and deceleration effects).</li>
		<li>Conduct the timed up and go (TUG) test20. Ask the patient to perform three consecutive TUG trials (stand up, walk 3 m, turn, walk back, and sit down) at a self-selected pace (for safety and comfort).</li>
	</ol>
	</li>
	<li>Perform the three-dimensional (3D) gait analysis (optional). 
	NOTE: 3D gait and concurrent electromyography (EMG) analyses are not required for this LBPP training protocol, but can be used for further objective assessments as needed.
	<ol>
		<li>Position twenty-two spherical markers on the patient&#8217;s anatomical landmarks based on the Davis protocol21.</li>
		<li>Position six surface EMG electrodes on the bilateral rectus femoris, semitendinosus, and long head biceps femoris of the patient.</li>
		<li>Perform calibration in the standing position. Ask the patient to hold an orthostatic position for at least 3&#8722;5 s with the feet aligned in order to avoid having one foot in a more anterior or posterior position with respect to the other.</li>
		<li>Instruct the patient to walk with a self-selected speed along the 5-m walkway, five times.</li>
		<li>Remove all the spherical markers and EMG electrodes from the patient. Save all the collected data for data processing later following the instructions in section.</li>
	</ol>
	</li>
</ol>
3. LBPP training
NOTE: An anti-gravity treadmill (Table of Materials) was used for this LBPP training protocol and shown in Figure 1. For patient safety, a therapist is required to set up the patient in the LBPP and supervise the whole treatment process.
<ol>
	<li>Preparation
	<ol>
		<li>Patient preparation
		<ol>
			<li>Introduce the specific LBPP treadmill training process and related precautions to the patient.</li>
			<li>Check the patient&#8217;s blood pressure (BP) and heart rate (HR) before training (60 bpm &#8804; HR &#8804; 120 bpm and 90/60 mmHg &#8804; BP &#8804; 160/100 mmHg).</li>
			<li>Determine the size of the air seal shorts according to the waist circumference of the patient and ask the patient to put on the shorts.</li>
		</ol>
		</li>
		<li>Anti-gravity treadmill setting up
		<ol>
			<li>Turn on the treadmill by operating the switch located on the front cover of the system and run the self-testing of the anti-gravity treadmill.</li>
			<li>Lower the cockpit and have the patient step into the fabric enclosure of the anti-gravity treadmill.</li>
			<li>Lift the cockpit to the appropriate height according to the LBPP training model: the cockpit height should be at the anterior superior iliac spine for the walking model and slightly below the femur&#8217;s greater trochanter for the squatting model. Once the cockpit is in place, zip the patient into the anti-gravity treadmill.</li>
			<li>Use the safety lanyard supplied with the machine to secure the clip onto patient&#8217;s clothing, which is essential for emergency stopping during the training process (in case the patient falls or does not feel well).</li>
			<li>Instruct the patient to stand still on the surface of the treadmill belt to allow the system to hold and weigh the patient&#8217;s full body weight (BW) without any support from any part of the system and then press the start button to perform an anti-gravity treadmill system calculation for accurate unweighting.</li>
			<li>Place three cameras supplied with the machine (in front and bilaterally, Figure 1) and adjust the positions to obtain the synchronized video feedback during the training process; this will help the patient correct abnormal movement patterns.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Training session 
	NOTE: The whole training session is performed for 30 min, six times a week for two weeks. The main parameters that need to be adjusted with the &#8220;+&#8221; and &#8220;&#8211;&#8221; button controls in the LBPP console are speed (miles per hour, mph), BW support (%), incline (%) and knee&#8217;s active range-of-motion (AROM).
	<ol>
		<li>Start the warm-up session with the following settings: 5 min (speed = 0&#8722;2.0 mph, BW = 65%, incline = 0%). Increase speed by 0.4 mph and BW support in 7% increments per minute.</li>
		<li>Perform the walking model session with the following settings: 15 min (speed = 2.0 mph, BW = 65%, incline = 0%).</li>
		<li>Perform the cool-down session with the following settings: 5 min (speed = 2.0&#8722;0 mph, BW = 65%&#8722;100%, incline = 0%). Decrease speed by 0.4 mph and BW support in 7% decrements per minute.</li>
		<li>End up with the squatting model session with the following settings: 5 min (speed = 0 mph, BW = 50%, incline = 0%, AROM = 0&#176;&#8722;50&#176; or the maximum tolerable joint range of motion within 50&#176;, 30 s of squatting followed by a 30 s rest period).		 NOTE: In the clinical application, this LBPP training session should be adjusted according to the patient&#8217;s tolerance. Moreover, if the patient cannot tolerate the squatting training model, only the walking mode is performed.</li>
	</ol>
	</li>
</ol>
4. Post-training evaluation
NOTE: The same therapist completes each patient&#39;s pre- and post-evaluation.
<ol>
	<li>Re-evaluate the patient after 2 weeks of the LBBP training session, including NRS, active/passive ROM, WOMAC, KOOS, EQ-5D, 10 MWT, TUG and 3D gait analysis.</li>
	<li>Record patient&#8217;s satisfaction and feedback on this LBPP protocol including the degree of enjoyment and self-conscious improvement, desire to continue, and suggestions.</li>
</ol>
5. 3D gait analysis data processing
<ol>
	<li>Run the gait analysis software (Table of Materials) included with the 3D gait analysis system.</li>
	<li>Define the events of heel-strike (right/left foot initial ground contact) and toe-off (right/left toes are lifted off the ground) in gait cycle for each walking trial (Figure 2).</li>
	<li>Obtain the spatiotemporal parameters, knee joint kinematics and surface EMG activity parameters.</li>
</ol>

<ol>
	<li>McAlindon, T. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=OARSI+guidelines+for+the+non-surgical+management+of+knee+osteoarthritis.">OARSI guidelines for the non-surgical management of knee osteoarthritis.</a> Osteoarthritis Cartilage. 22, 363-388 (2014).</li><li>Luyten, F. P., Denti, M., Filardo, G., Kon, E., Engebretsen, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Definition+and+classification+of+early+osteoarthritis+of+the+knee.">Definition and classification of early osteoarthritis of the knee.</a> Knee Surgery Sports Traumatology Arthroscopy. 20, 401-406 (2012).</li><li>Lankhorst, G. J., Van de Stadt, R. J., Van der Korst, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationships+of+functional+capacity,+pain,+and+isometric+and+isokinetic+torque+in+osteoarthrosis+of+the+knee.">The relationships of functional capacity, pain, and isometric and isokinetic torque in osteoarthrosis of the knee.</a> Scandinavian Journal of Rehabilitation Medicine. 17, 167-172 (1985).</li><li>Waugh, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+activity+intervention+in+primary+care+and+rheumatology+for+the+management+of+knee+osteoarthritis:+A+review.">Physical activity intervention in primary care and rheumatology for the management of knee osteoarthritis: A review.</a> Arthritis Care &amp; Research. 71 (2), 189-197 (2019).</li><li>Segal, N. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+quadriceps+strength+and+proprioception+on+risk+for+knee+osteoarthritis.">Effect of quadriceps strength and proprioception on risk for knee osteoarthritis.</a> Medicine &amp; Science in Sports &amp; Exercise. 42, 2081 (2010).</li><li>Linda, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EULAR+recommendations+for+the+non-pharmacological+core+management+of+hip+and+knee+osteoarthritis.">EULAR recommendations for the non-pharmacological core management of hip and knee osteoarthritis.</a> Annals of the Rheumatic Diseases. 72, 1125-1135 (2013).</li><li>Watanabe, S., Someya, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+Body+Weight-supported+Walking+on+Exercise+Capacity+and+Walking+Speed+in+Patients+with+Knee+Osteoarthritis:+A+Randomized+Controlled+Trial.">Effect of Body Weight-supported Walking on Exercise Capacity and Walking Speed in Patients with Knee Osteoarthritis: A Randomized Controlled Trial.</a> Journal of the Japanese Physical Therapy Association. 16, 28-35 (2013).</li><li>Takacs, J., Anderson, J. E., Leiter, J. R., MacDonald, P. B., Peeler, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lower+body+positive+pressure:+an+emerging+technology+in+the+battle+against+knee+osteoarthritis?.">Lower body positive pressure: an emerging technology in the battle against knee osteoarthritis?.</a> Clinical Interventions in Aging. 8, 983-991 (2013).</li><li>Ruckstuhl, H., Kho, J., Weed, M., Wilkinson, M. W., Hargens, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparing+two+devices+of+suspended+treadmill+walking+by+varying+body+unloading+and+Froude+number.">Comparing two devices of suspended treadmill walking by varying body unloading and Froude number.</a> Gait &amp; Posture. 30, 446-451 (2009).</li><li>Peeler, J., Christian, M., Cooper, J., Leiter, J., MacDonald, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Managing+Knee+Osteoarthritis:+The+Effects+of+Body+Weight+Supported+Physical+Activity+on+Joint+Pain,+Function,+and+Thigh+Muscle+Strength.">Managing Knee Osteoarthritis: The Effects of Body Weight Supported Physical Activity on Joint Pain, Function, and Thigh Muscle Strength.</a> Clinical Journal of Sport Medicine. 25, 518-523 (2015).</li><li>Patil, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anti-gravity+treadmills+are+effective+in+reducing+knee+forces.">Anti-gravity treadmills are effective in reducing knee forces.</a> Journal of Orthopaedic Research. 31, 672-679 (2013).</li><li>Nicolas-Alonso, L. F., Gomez-Gil, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brain+computer+interfaces,+a+review.">Brain computer interfaces, a review.</a> Sensors (Basel). 12, 1211-1279 (2012).</li><li>Webber, S. C., Horvey, K. J., Yurach Pikaluk, M. T., Butcher, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiovascular+responses+in+older+adults+with+total+knee+arthroplasty+at+rest+and+with+exercise+on+a+positive+pressure+treadmill.">Cardiovascular responses in older adults with total knee arthroplasty at rest and with exercise on a positive pressure treadmill.</a> European Journal of Applied Physiology. 114, 653-662 (2014).</li><li>Dolphin, N. W., Crue, B. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pain:+Clinical+Manual+For+Nursing+Practice.">Pain: Clinical Manual For Nursing Practice.</a> Clinical Journal of Pain. 5, 363 (1989).</li><li>Lavernia, C., D'Apuzzo, M., Rossi, M. D., Lee, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+Knee+Range+of+Motion+Assessment+After+Total+Knee+Arthroplasty.">Accuracy of Knee Range of Motion Assessment After Total Knee Arthroplasty.</a> The Journal of Arthroplasty. 23, 85-91 (2008).</li><li>Bellamy, N., Buchanan, W. W., Goldsmith, C. H., Campbell, J., Stitt, L. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+study+of+WOMAC:+a+health+status+instrument+for+measuring+clinically+important+patient+relevant+outcomes+to+antirheumatic+drug+therapy+in+patients+with+osteoarthritis+of+the+hip+or+knee.">Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee.</a> Journal of Rheumatology. 15, 1833-1840 (1988).</li><li>Collins, N. J., Misra, D., Felson, D. T., Crossley, K. M., Roos, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measures+of+knee+function:+International+Knee+Documentation+Committee+(IKDC)+Subjective+Knee+Evaluation+Form,+Knee+Injury+and+Osteoarthritis+Outcome+Score+(KOOS),+Knee+Injury+and+Osteoarthritis+Outcome+Score+Physical+Function+Short+Form+(KOOS-PS)+Knee+O.">Measures of knee function: International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Knee Injury and Osteoarthritis Outcome Score (KOOS), Knee Injury and Osteoarthritis Outcome Score Physical Function Short Form (KOOS-PS) Knee O.</a> Arthritis Care &amp; Research. 63, S208-S228 (2011).</li><li>Rabin, R., De-Charro, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EQ-5D:+a+measure+of+health+status+from+the+EuroQol+Group.">EQ-5D: a measure of health status from the EuroQol Group.</a> Annals of Medicine. 33, 337-343 (2001).</li><li>Wirz, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effectiveness+of+automated+locomotor+training+in+patients+with+chronic+incomplete+spinal+cord+injury:+a+multicenter+trial.">Effectiveness of automated locomotor training in patients with chronic incomplete spinal cord injury: a multicenter trial.</a> Archives of Physical Medicine and Rehabilitation. 86, 672-680 (2005).</li><li>Shumway-Cook, A., Baldwin, M., Polissar, N. L., Gruber, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predicting+the+probability+for+falls+in+community-dwelling+older+adults.">Predicting the probability for falls in community-dwelling older adults.</a> Physical Therapy. 77, 812-819 (1997).</li><li>Iii, R. B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+gait+analysis+data+collection+and+reduction+technique.">A gait analysis data collection and reduction technique.</a> Human Movement Science. 10, 575-587 (1991).</li><li>Peeler, J., Ripat, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+low-load+exercise+on+joint+pain,+function,+and+activities+of+daily+living+in+patients+with+knee+osteoarthritis.">The effect of low-load exercise on joint pain, function, and activities of daily living in patients with knee osteoarthritis.</a> Knee. 25 (1), 135-145 (2018).</li><li>Escamilla, R. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Knee+biomechanics+of+the+dynamic+squat+exercise.">Knee biomechanics of the dynamic squat exercise.</a> Medicine &amp; Science in Sports &amp; Exercise. 33, 127-141 (2001).</li><li>Linschoten, R. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+PEX+study+&#8211;+Exercise+therapy+for+patellofemoral+pain+syndrome:+design+of+a+randomized+clinical+trial+in+general+practice+and+sports+medicine+[ISRCTN83938749].">The PEX study &#8211; Exercise therapy for patellofemoral pain syndrome: design of a randomized clinical trial in general practice and sports medicine [ISRCTN83938749].</a> BMC Musculoskeletal Disorders. 7, 31 (2006).</li></ol>

The authors have nothing to disclose.

We proposed an LBPP treadmill intervention protocol, which includes both clinical assessment and treatment models, for the rehabilitation of lower extremity motor function in knee OA. Meanwhile, in response to the clinical symptoms and knee OA dysfunction, the treatment model includes not only a training section for walking in the LBPP protocol but also an innovative squatting training section, which aims to solve the daily dysfunction due to thigh muscle weakness and squatting difficulties in knee OA patients. To the be...

Knee osteoarthritis (OA) is a progressive degenerative joint condition and a major cause of pain and locomotor disability in people all over the world1. Knee OA is characterized by osteophyte and cyst formation, narrow joint spacing, and subchondral bone sclerosis2. These pathological changes make it difficult to perform essential activities of daily living such as walking, squatting, and going up and down stairs3. However, physical activity is recommended as an essential component of first-line knee OA management4. Exercise intervention for knee OA rehabilitation is affected by several factors: (1) limited knee joint movement caused by pain and minor knee structural changes; (2) muscle atrophy associated with maintaining knee stability and a decrease in muscle strength5; and (3) the above reasons lead to a reduction in exercise and an increase in body mass index (BMI), which further increases the burden on the knees, thus creating a vicious cycle6.
In response to the above mentioned issues, the body weight-supported training system (BWSTT) has gradually addressed bone and joint disease-related rehabilitation7. In recent years, one of the emerging body weight-supported training technologies is called the lower body positive pressure (LBPP) treadmill7. This technology uses a waist-high inflatable balloon to achieve positive lower limb pressure and accurately adjust the air pressure to regulate body weight with the aim of achieving weight reduction. The system is also equipped with a running platform that can concurrently perform treadmill-related activities under the control of body weight8. Meanwhile, the pressure generated in the inflated enclosure provides a lifting force against the body. Because the pressure is only slightly above atmospheric pressure and is evenly distributed, the force on the lower body is almost imperceptible. Thus, the LBPP running platform provides a higher level of comfort and is more suitable for long-term training compared with the traditional BWSTT9. Peeler et al. performed an LBPP treadmill intervention on 32 knee OA patients and showed that the LBPP treadmill can effectively relieve knee pain, improve daily life functions, and produce an increase in thigh muscle strength10. The potential mechanism might be related to achievement of effective knee joint activity while reducing knee joint torque11. On the other hand, since the age of onset of knee OA patients is mostly over 45 years old12, onset may also be associated with cardio-pulmonary diseases. Studies have shown that LBPP allows people to achieve walking as exercise with relatively low heart rate, blood pressure, and oxygen consumption and achieve safer and more effective aerobic exercise than full-weight flat walking; this type of walking is another advantage of LBPP when compared with traditional BWSTT13.
However, due to the relatively new application of this system to knee OA intervention, the relatively few existing studies have greatly limited the clinical application of this technology in knee OA rehabilitation. The LBPP protocol proposed in this article aimed to explore the clinical non-drug and surgical knee OA treatment using the LBPP treadmill.

<table>
	<tbody>
		<tr>
			<td>AlterG Anti-Gravity Treadmill M320</td>
			<td>AlterG Inc, Fremont, CA, USA</td>
			<td>1</td>
			<td>LBBP training</td>
		</tr>
		<tr>
			<td>BTS Smart DX system</td>
			<td>Bioengineering Technology System, Milan, Italy</td>
			<td>2</td>
			<td>Temporospatial data collection</td>
		</tr>
		<tr>
			<td>BTS FREEEMG</td>
			<td>Bioengineering Technology System, Milan, Italy</td>
			<td>3</td>
			<td>Surface EMG data collection</td>
		</tr>
		<tr>
			<td>BTS SMART-Clinic software</td>
			<td>Bioengineering Technology System, Milan, Italy</td>
			<td>4</td>
			<td>Data processing</td>
		</tr>
	</tbody>
</table>

the lower body positive pressure treadmill for knee osteoarthritis rehabilitation

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

We show results from a knee OA patient, who was a 60-year-old female (BMI = 22.9) undergoing &#8220;more than 3 years of knee osteoarthritis&#8221; and severe pain when she was walking (visual analog scale [VAS] = 8/10) and participated in a 2-week LBPP training program at our facility. During the entire intervention, the patient did not take any painkillers to relieve knee pain. The radiological image of her knee joints and the results of clinical function assessments are shown in Figure 3 ...

Watch this Scientific Journal Video about The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation at JoVE.com

The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation

Here, based on a clinician&#8217;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in ...

the-lower-body-positive-pressure-treadmill-for-knee-osteoarthritis

Research

JoVE Journal

Medicine

10.3K Views.  The Fifth Affiliated Hospital of Guangzhou Medical University. Here, based on a clinician’s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-d...

Video: The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance

Orthostatic tolerance (OT) refers to the ability to maintain cardiovascular stability when upright, against the hydrostatic effects of gravity, and hence to maintain cerebral perfusion and prevent syncope (fainting). Various techniques are available to assess OT and the effects of gravitational stress upon the circulation, typically by reproducing a presyncopal event (near-fainting episode) in a controlled laboratory environment. The time and/or degree of stress required to provoke this response provides the measure of OT. Any technique used to determine OT should: enable distinction between patients with orthostatic intolerance (of various causes) and asymptomatic control subjects; be highly reproducible, enabling evaluation of therapeutic interventions; avoid invasive procedures, which are known to impair OT1.
In the late 1980s head-upright tilt testing was first utilized for diagnosing syncope2. Since then it has been used to assess OT in patients with syncope of unknown cause, as well as in healthy subjects to study postural cardiovascular reflexes2-6. Tilting protocols comprise three categories: passive tilt; passive tilt accompanied by pharmacological provocation; and passive tilt with combined lower body negative pressure (LBNP). However, the effects of tilt testing (and other orthostatic stress testing modalities) are often poorly reproducible, with low sensitivity and specificity to diagnose orthostatic intolerance7.
Typically, a passive tilt includes 20-60 min of orthostatic stress continued until the onset of presyncope in patients2-6. However, the main drawback of this procedure is its inability to invoke presyncope in all individuals undergoing the test, and corresponding low sensitivity8,9. Thus, different methods were explored to increase the orthostatic stress and improve sensitivity.
Pharmacological provocation has been used to increase the orthostatic challenge, for example using isoprenaline4,7,10,11 or sublingual nitrate12,13. However, the main drawback of these approaches are increases in sensitivity at the cost of unacceptable decreases in specificity10,14, with a high positive response rate immediately after administration15. Furthermore, invasive procedures associated with some pharmacological provocations greatly increase the false positive rate1.
Another approach is to combine passive tilt testing with LBNP, providing a stronger orthostatic stress without invasive procedures or drug side-effects, using the technique pioneered by Professor Roger Hainsworth in the 1990s16-18. This approach provokes presyncope in almost all subjects (allowing for symptom recognition in patients with syncope), while discriminating between patients with syncope and healthy controls, with a specificity of 92%, sensitivity of 85%, and repeatability of 1.1&plusmn;0.6 min16,17. This allows not only diagnosis and pathophysiological assessment19-22, but also the evaluation of treatments for orthostatic intolerance due to its high repeatability23-30. For these reasons, we argue this should be the "gold standard" for orthostatic stress testing, and accordingly this will be the method described in this paper.

We describe a "gold standard" for evaluating orthostatic tolerance (OT) using tilt testing with combined lower body negative pressure (LBNP). This can be combined with non-invasive evaluations of cardiovascular reflex control. Normal and abnormal responses are defined.

Orthostatic tolerance (OT)  refers to the ability to maintain cardiovascular stability when upright,  against the hydrostatic effects of gravity, and ...

Using a Knee Arthrometer to Evaluate Tissue-specific Contributions to Knee Flexion Contracture in the Rat

Normal knee range of motion (ROM) is critical to well-being and allows one to perform basic activities such as walking, climbing stairs and sitting. Lost ROM is called a joint contracture and results in increased morbidity. Due to the difficulty of reversing established knee contractures, early detection is important, and hence, knowing risk factors for their development is essential. The rat represents a good model with which the effect of an intervention can be studied due to the similarity of rat knee anatomy to that of humans, the rat's ability to tolerate long durations of knee immobilization in flexion, and because mechanical data can be correlated with histologic and biochemical analysis of knee tissue.
Using an automated arthrometer, we demonstrate a validated, precise, reproducible, user-independent method of measuring the extension ROM of the rat knee joint at specific torques. This arthrometer can be used to determine the effects of interventions on knee joint ROM in the rat.

The goal of the protocol is to measure the extension range of motion of the rat knee. The effects of various diseases that increase the stiffness of the knee joint and the effectiveness of treatments can be quantified.

Normal knee range of motion (ROM) is critical to well-being and allows one to perform basic activities such as walking, climbing stairs and sitting. Lost ...

FSN Therapy for Knee Osteoarthritis Pain Management

Fu's Subcutaneous Needling for Knee Osteoarthritis Pain

Fu's subcutaneous needling (FSN) is a new acupuncture and dry needling technique based on traditional Chinese medicine. It rapidly produces long-lasting effects in soft tissue injuries, particularly in painful musculoskeletal conditions, by providing stimulation primarily in the subcutaneous area. Osteoarthritis (OA) is the most common joint disease in adults worldwide and is often accompanied by a painful syndrome of structural changes in the peripheral joints of the knee. However, the etiology of OA pain is not fully understood, though myofascial trigger points (MTrPs) are commonly found in the lower limb muscles (so-called "tightened muscles") of patients with knee OA. 
FSN has been used in many fields for the treatment of acute pain problems and can relieve muscle contraction from MTrPs, thereby improving the local circulation. This study recruited patients with pain from knee OA into an FSN group or a transcutaneous electrical nerve stimulation (TENS) group with three treatment sessions and a follow-up over the course of 2 weeks. The results showed that FSN was effective in treating soft tissue pain around the knee with OA. This study aimed to establish and visualize three key technical indicators during FSN therapy, including the FSN needle insertion point and layer; the frequency and duration of the swaying movement; and the manipulation of the reperfusion approach. These findings have great potential for future applications in myofascial pain treatment, especially for pain management. Following this protocol could enhance FSN skills.

Author Spotlight: Fu's Subcutaneous Needling for Knee Osteoarthritis Pain  

We present a protocol for using Fu's subcutaneous needling for knee osteoarthritis pain, which combines swaying movement and reperfusion approach techniques. This protocol has great potential for future applications in myofascial pain treatment and could enhance Fu's subcutaneous needling (FSN) manipulation skills.

Fu's subcutaneous needling (FSN) is a new acupuncture and dry needling technique based on traditional Chinese medicine. It rapidly produces long-lasting ...

Performing Fu's Subcutaneous Needling for Degenerative Knee Osteoarthritis

Treating Knee Osteoarthritis with Tuina in a Rabbit Model

Tuina Intervention in Rabbit Model of Knee Osteoarthritis

Knee osteoarthritis (KOA) is mainly characterized by degenerative changes in the knee joint's cartilage and surrounding soft tissues. The efficacy of Tuina in treating KOA has been confirmed, but the underlying mechanism needs to be investigated. This study aims to establish a scientifically feasible KOA rabbit model treated with Tuina to reveal the underlying mechanisms. For this, 18, 6-month-old normal-grade male New Zealand rabbits were randomly divided into sham, model, and Tuina groups, with 6 rabbits in each group. The KOA model was established by injecting 4% papain solution into the knee joint cavity. The Tuina group was intervened with Tuina combined with the knee joint rotary correction method for 4 weeks. Only the standard grasping and fixation were performed in sham and model groups. At the end of the 1-week intervention, the knee joint range of motion (ROM) was observed, and cartilage hematoxylin-eosin (HE) staining was done. The study shows that Tuina could inhibit chondrocyte apoptosis, repair cartilage tissue, and restore knee joint ROM. In conclusion, this study demonstrates the scientific feasibility of Tuina treatment for KOA model rabbits, highlighting its potential application in the study of KOA and similar knee joint-related conditions.

Author Spotlight: Using a Rabbit Model to Explore the Efficacy of Tuina in Treating Knee Osteoarthritis 

The protocol describes a method for Tuina intervention in a rabbit model of knee osteoarthritis.

Knee osteoarthritis (KOA) is mainly characterized by degenerative changes in the knee joint's cartilage and surrounding soft tissues. The efficacy of ...

Establishment of the KOA Model in Rabbits Using the Modified Videman Method

Application of Acupotomy in a Knee Osteoarthritis Model in Rabbit

Knee osteoarthritis (KOA) is one of the most frequently encountered diseases in the orthopedic department, which seriously reduces the quality of life of people with KOA. Among several pathogenic factors, the biomechanical imbalance of the knee joint is one of the main causes of KOA. Acupotomology believes that restoring the mechanical balance of the knee joint is the key to treating KOA. Clinical studies have shown that acupotomy can effectively reduce pain and improve knee mobility by reducing adhesion, contracture of soft tissues, and stress concentration points in muscles and tendons around the knee joint. 
In this protocol, we used the modified Videman method to establish a KOA model by immobilizing the left hindlimb in a straight position. We have outlined the method of operation and the precautions related to acupotomy in detail and evaluated the efficacy of acupotomy in conjunction with the theory of "Modulating Muscles and Tendons to Treat Bone Disorders" through the detection of the mechanical properties of quadriceps femoris and tendon, as well as cartilage mechanics and morphology. The results show that acupotomy has a protective effect on cartilage by adjusting the mechanical properties of the soft tissues around the knee joint, improving the cartilage stress environment, and delaying cartilage degeneration.

Author Spotlight: Investigating the Mechanism of Action of Acupotomy in Treating Knee Osteoarthritis

In this protocol, a knee osteoarthritis model was prepared using the modified Videman method, and the operation procedures and precautions of acupotomy are detailed. The effectiveness of acupotomy has been demonstrated by testing the mechanical properties of quadriceps femoris and tendon and the mechanical and morphological properties of cartilage.

Knee osteoarthritis (KOA) is one of the most frequently encountered diseases in the orthopedic department, which seriously reduces the quality of life of ...

Therapeutic Potential of Tuina Massage for Knee Osteoarthritis

Tuina Intervention in Sodium Monoiodoacetate Injection-Induced Rat Model of Knee Osteoarthritis

Knee osteoarthritis (KOA), a common degenerative joint disorder, is characterized by chronic pain and disability, which can progress to irreparable structural damage of the joint. Investigations into the link between articular cartilage, muscles, synovium, and other tissues surrounding the knee joint in KOA are of great importance. Currently, managing KOA includes lifestyle modifications, exercise, medication, and surgical interventions; however, the elucidation of the intricate mechanisms underlying KOA-related pain is still lacking. Consequently, KOA pain remains a key clinical challenge and a therapeutic priority. Tuina has been found to have a regulatory effect on the motor, immune, and endocrine systems, prompting the exploration of whether Tuina could alleviate KOA symptoms, caused by the upregulation of inflammatory factors, and further, if the inflammatory factors in skeletal muscle can augment the progression of KOA.
We randomized 32 male Sprague Dawley (SD) rats (180-220 g) into four groups of eight animals each: antiPD-L1+Tuina (group A), model (group B), Tuina (group C), and sham surgery (group D). For groups A, B, and C, we injected 25 &#181;L of sodium monoiodoacetate (MIA) solution (4 mg MIA diluted in 25 &#181;L of sterile saline solution) into the right knee joint cavity, and for group D, the same amount of sterile physiological saline was injected. All the groups were evaluated using the least to most stressful tests (paw mechanical withdrawal threshold, paw withdrawal thermal latency, swelling of the right knee joint, Lequesne MG score, skin temperature) before injection and 2, 9, and 16 days after injection.

Author Spotlight: Treating Knee Osteoarthritis with Tuina - A New Perspective 

This protocol describes the methods of Tuina intervention in sodium monoiodoacetate injection-induced rat model of knee osteoarthritis (KOA), which provides a reference for the application of Tuina in KOA animal models. This protocol also studies the effective mechanism of Tuina for KOA, and the results will help promote its application.

Knee osteoarthritis (KOA), a common degenerative joint disorder, is characterized by chronic pain and disability, which can progress to irreparable ...

Performing Tuina on Knee Osteoarthritis (KOA) Rabbit Model

Rehabilitation Treatment Plan for ACLR Patients

Early Weight-Bearing Rehabilitation Protocol After Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) injury is one of the common sports injuries. Anterior cruciate ligament reconstruction (ACLR) is the mainstream treatment for ACL injury, aiming to regain normal anatomical structure and stability of the knee joint and promote the patient's return to sports. Under the guidance of the concept of enhanced recovery after surgery, early weight-bearing rehabilitation (EWB) is an important factor affecting patient function and quality of life. However, there is no consensus on whether EWB rehabilitation can be performed after ACL surgery. 
This study aims to explore the safety and feasibility of EWB after ACL surgery. The study implemented a gradual EWB rehabilitation program in the experimental group, including weight-shifting training, balance training, and gait training on the affected lower limb, and assessed wound healing and stability of the knee joint. The study found that EWB after ACLR is safe and feasible. EWB rehabilitation not only does not pose a negative effect on the patient's knee pain, swelling, wound healing, and stability, but also helps to improve knee active flexion and quality of life faster and better. The EWB program in this study is simple, safe, and effective, and it provides strong theoretical guidance and practical demonstration for accelerated rehabilitation after ACLR.

Author Spotlight: Implementing the Enhanced Recovery After Surgery Concept in Rehabilitation Following Anterior Cruciate Ligament Reconstruction

Based on the safety and feasibility, this article presents an early weight-bearing rehabilitation protocol after anterior cruciate ligament reconstruction. The protocol is clear and easy to operate, which is helpful to promote its use in clinical practice and accelerate the functional recovery of patients.

Anterior cruciate ligament (ACL) injury is one of the common sports injuries. Anterior cruciate ligament reconstruction (ACLR) is the mainstream treatment ...

Managing Knee Osteoarthritis Using Ultrasound-Guided Acupotomy

Clinical Effects of Ultrasound-Guided Acupotomy in Knee Osteoarthritis Treatment

The protocol presented here demonstrates the operation method of ultrasound-guided acupotomy for knee osteoarthritis (KOA), including patient recruitment, preoperative preparation, manual operation, and postoperative care. The purpose of this protocol is to relieve pain and improve knee function in patients with KOA. A total of 60 patients with KOA admitted between June 2022 and June 2023 were treated with ultrasound-guided acupotomy. Pathological changes and knee function scores were compared before and after the treatment. After 1 week of treatment, the synovial thickness of the suprapatellar bursae was significantly lesser than before treatment (p &lt; 0.05), the Hospital for Special Surgery Knee Score (HSS) was significantly higher than before treatment (p &lt; 0.05), the Visual analogue scale (VAS) was significantly lower than those of the control group (p &lt; 0.05) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were significantly lower than those of the control group (p &lt; 0.05). Therefore, ultrasound-guided acupotomy for the treatment of KOA can reduce synovial thickness, relieve pain, improve knee joint function, and have a remarkable curative effect.

Author Spotlight: Minimally Invasive Ultrasound-Guided Acupotomy in Knee Osteoarthritis Treatment

This paper introduces the operation method of ultrasound-guided acupotomy for knee osteoarthritis, which can reduce synovial thickness and improve knee joint function. It has the advantages of precise target, low treatment risk, few complications, and high safety.

The protocol presented here demonstrates the operation method of ultrasound-guided acupotomy for knee osteoarthritis (KOA), including patient recruitment, ...