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A randomized controlled trial: Acupotomy Arthroscope vs. arthroscopic intervention in knee OA patients' gait and symptoms
, Cheng Gea,c, Yang Zhanga,c, Shihui Wanga,c, Yunwen Gaoa,c, Yinghui Maa,c
⁎Corresponding author: Shaodan Cheng. chengshaodannew@126.com
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Received: ,
Accepted: ,
This article was originally published by Reed Elsevier India Pvt. Ltd. and was migrated to Scientific Scholar after the change of Publisher.
Abstract
Abstract
This study aimed to compare the effects of Acupotomy Arthroscope and Arthroscopic interventions on gait and symptoms in patients with Knee Osteoarthritis (KOA).
In a single-blind, randomized trial, 73 KOA patients were assigned to receive either Acupotomy Arthroscope or Arthroscopic treatment. The primary outcomes measured were pre- and post-intervention gait spatiotemporal and kinematic parameters. Secondary outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Knee Society Score (KSS).
Both groups exhibited significant improvements in gait parameters and reductions in WOMAC scores, with increases in KSS post-intervention (P < 0.01). The Acupotomy Arthroscope group demonstrated better improvements in gait cycle times and knee flexion angles, although it was less effective in enhancing walking speed.
Both interventions effectively enhanced gait biomechanics and reduced joint symptoms. Acupotomy Arthroscope was more effective in improving short-term clinical symptoms and functional capacity, while Arthroscopic treatment was superior for pain and mobility limitations.
Keywords
Knee osteoarthritis
Acupotomy arthroscope
Arthroscopic
Gait analysis
1 Introduction
KOA is a prevalent clinical condition characterized by chronic and degenerative changes in the joint, primarily manifesting as knee pain and compromised joint function.1 This condition impacts various joint tissues, causing discomfort and disability in routine activities.2 Individuals with KOA frequently display aberrant gait biomechanics, potentially exacerbating the disease's progression.3 Both symptomatic and asymptomatic KOA patients exhibit a diminished peak Knee Extension Moment (KEM), a phenomenon also observed in those with radiographic evidence of KOA without symptoms. Additionally, the range of knee flexion during the stance phase and the Vertical Ground Reaction Force (vGRF) are reduced in KOA patients compared to their non-KOA counterparts.4 These reductions are indicative of a "stiff knee" gait, which may alter the tibiofemoral joint's contact mechanics and contribute to adverse changes in KOA progression (see Tables 4–8, Scheme 1) (Tables 4–8, Scheme 1).
While conventional arthroscopic debridement shows limited efficacy in moderate-severe knee OA, our pilot study revealed that 68 % of non-responsive cases had significant extra-articular soft tissue adhesions undetectable by standard imaging. The Acupotomy Arthroscope uniquely addresses both intra-articular pathology and periarticular adhesions through its integrated design. This RCT aims to test the hypothesis that combined intervention improves gait symmetry by ≥ 15 % compared to standard approaches.
The Acupotomy Arthroscope represents an innovation in minimally invasive techniques, building upon the principles of traditional small needle knife therapy and integrating modern endoscopic and surgical technologies. This approach allows for direct visualization during the procedure, emphasizing precision and minimal invasiveness. Guided by Traditional Chinese Medicine theories, the Acupotomy Arthroscope method preserves the integrity of the overall structure while enabling targeted treatments such as decompression, separation, irrigation, and medication placement. It has been extensively applied in managing joint and soft tissue pain conditions, particularly in KOA. This therapy has been shown to enhance joint mobility, alleviate pain, and improve functionality in KOA patients. The present study aims to assess the impact of Acupotomy Arthroscope on the gait biomechanics of individuals with KOA.
2 Materials and methods
2.1 Acupotomy Arthroscope: instrument design and Working Principles
Structural Details:
The Acupotomy Arthroscope is composed of an imaging system, a flushing system, and its probe needle medical device. The Acupotomy Arthroscope integrates an arthroscopy lens and a retractable needle-knife system. The needle hole only requires 0.5 cm, allowing the establishment of a needle channel to complete the entire diagnostic and treatment process with minimal needle injury. Visual operation: Needle manipulation is performed under visual conditions, reducing the risk of operation and improving therapeutic efficacy(Table 1.).
| Feature | Acupotomy Arthroscope | Standard Arthroscope |
| Channel Diameter | 0.5 cm (Single-needle access) | 1.0 cm (Dual-port required) |
| Tool Integration | Retractable needle-knife system | Separate instrument channels |
| Anesthesia | Local anesthesia feasible | General/regional anesthesia |
| Adhesion Management | Simultaneous release under vision | Limited to debridement |
Working Principle:
During Acupotomy Arthroscope treatment, there is minimal trauma and bleeding, both of which can be carried out under local anesthesia without the need for a tourniquet. During the treatment, physiological saline can be injected into the joint cavity through the channel to expand the joint space, providing a clear surgical field of view, allowing the surgeon to perform precise surgical treatment. Fewer surgical channels and smaller incisions result in less trauma, and consequently, a lower probability of infection; the entire surgery is irrigated with physiological saline, which effectively inhibits and dilutes microbial proliferation; local anesthesia is used without a tourniquet during the procedure, ensuring good blood circulation and preserving the patient's immune function to the greatest extent possible. During the surgical process, the needle-knife releases adhesions in the surrounding soft tissues of the joint through the lateral channel of the instrument, while the integrated camera provides real-time monitoring (Fig. 1.)
Structural Differentiation.
2.2 Study design and participants
This prospective, single-center, single-blind randomized controlled trial assesses the impact of Acupotomy Arthroscope (AA) versus Arthroscopy on Knee Osteoarthritis (KOA) patients. The trial is registered with the Chinese Clinical Trial Registry under the number ChiCTR2400083232 and has received ethical approval from the Guanghua Hospital of Integrated Traditional Chinese and Western Medicine in Shanghai (Ethics No.: 2024-K-48). Participants were enrolled from the Orthopedics Department of the same hospital, with a research assistant reaching out to interested individuals to mitigate expectation bias and verify eligibility.
Inclusion criteria included complete clinical records and adherence to the 2018 guidelines from both the Orthopedics Branch of the Chinese Medical Association and the Orthopedics Committee of the Chinese Integrative Medicine Society, which specify the following: persistent knee pain within the last month; characteristic X-ray findings such as joint space narrowing, subchondral bone changes, and osteophyte formation; MRI evidence of cartilage damage, bone marrow edema, and meniscal tears; age of 50 or above; morning stiffness not exceeding 30 min; and the presence of crepitus during movement.5,6 A diagnosis of KOA is made based on a combination of clinical and imaging findings that meet specific criteria.
The 2023 expert consensus on the integrative treatment of knee osteoarthritis also provided mid-stage Western medicine criteria, including frequent severe knee pain, limitations in daily activities due to pain, recurrent swelling, possible mild varus or valgus deformity, and characteristic X-ray features with a K-L grade of III.
Exclusion criteria were non-compliance with the aforementioned diagnostic and inclusion criteria, severe cognitive, visual, or auditory impairments that hinder understanding and communication, other limiting conditions such as cardiopulmonary, hepatorenal diseases, tumors, or musculoskeletal dysfunction, and concurrent surgeries during the perioperative period. Informed consent was obtained from all participants prior to baseline assessment. The study adheres to the CONSORT guidelines, with further details available in the supplementary file.
2.3 Interventions
2.3.1 Acupotomy Arthroscope group procedure
Patients are positioned supine with a small round cushion beneath the popliteal fossa, bending the knee joint to an angle of 30–60°. The anterior and posterior knee eye areas are marked with an oil-based marker to indicate the surgical approach (Schematic diagrams A). The affected knee is disinfected using povidone-iodine solution, followed by the application of a sterile drape. Local infiltration anesthesia is administered using 0.25 % lidocaine hydrochloride, progressively through the skin, fascia, muscle layers, joint capsule, and into the joint cavity (Schematic diagrams B). A small incision of approximately 0.3–0.4 cm is made at the lateral knee eye, and the Acupotomy Arthroscope is inserted to perform stripping of the superficial fascia and muscle layers. The joint capsule is then incised to create a pathway for the Acupotomy Arthroscope. The device's sheath is introduced, the core is removed, and the Acupotomy Arthroscope with an attached light is inserted. Physiological saline is connected to the irrigation inflow channel, and an exploration is conducted sequentially across the intercondylar fossa, lateral and medial compartments, menisci, patellofemoral joint, suprapatellar pouch, and the surfaces of the patella and femur (Schematic diagrams C). A similar approach is used at the medial knee eye to establish a channel for the introduction of blunt dissection tools, which are used to separate inflamed and abnormally proliferated tissues, as well as necrotic cartilage, from healthy tissue using a blunt dissection technique. Adhesions of the synovium and infrapatellar fat pad are also gently freed (Schematic diagrams D). Throughout the procedure, care is taken to prevent injury and minimize mechanical damage to the cartilage. Joint cavity irrigation is performed concurrently with the surgical manipulations, and negative pressure suction is utilized to remove as much fluid as possible from the joint cavity at the conclusion of the procedure (Schematic diagrams E). Instruments are then carefully removed, and a probe needle is used to perform routine subcutaneous fascia release on the anterior, medial, and lateral aspects of the knee joint, maintaining alignment with the femur's long axis and parallel to muscle fiber direction (Schematic diagrams F). Various techniques including longitudinal loosening, transverse stripping, cutting, and scraping are employed to thoroughly release adhesions, scars, and contractures around the knee joint, aiming to restore muscular balance in the area. At the end of the procedure, 2 mL of medical chitosan is injected into the joint cavity to prevent adhesions; the incision is closed with a single suture, dressed with sterile gauze, secured with a sterile adhesive, and compressed with an elastic bandage for 2 h. Patients are advised to keep the dressing dry and to commence active knee joint functional exercises within 24 h post-surgery. Dressing changes are scheduled daily, and sutures are removed after two weeks.
2.3.2 Arthroscopic group procedure
Patients undergo routine arthroscopic surgery using equipment from Smith & Nephew while in a supine position under spinal-epidural anesthesia. An upper thigh tourniquet is applied and set for 90 min with an inflation pressure adjusted between 33 and 40 kPa based on the patient's obesity level. The knee is positioned to hang naturally by the side of the operating table at a 40 to 50-degree angle. Two 1-cm incisions are made at the medial and lateral knee eyes to serve as portals for the arthroscope and surgical instruments. The surgery follows standard arthroscopic procedures, examining the knee joint from the suprapatellar pouch to the patellofemoral joint, medial and lateral femoral condyles, medial and lateral knee compartments, intercondylar notch, and posterior medial and lateral knee gaps. The internal structures are inspected for meniscal damage, chondromalacia, loose bodies, cruciate ligament laxity, and synovial fold abnormalities. Abnormalities are treated using radiofrequency probes, shavers, and plasma coagulation devices to remove osteophytes, trim unstable menisci, clear loose cartilage fragments, and address soft cartilage lesions. Synovial tissue is managed by scraping and shaving to remove congested and edematous areas. Post-surgery, the joint is inspected for bleeding, and any active bleeders are managed with electrocoagulation. The joint cavity is thoroughly irrigated with approximately 1500 mL of 0.8 % saline solution to flush out debris, followed by negative pressure suction to remove residual fluid. The arthroscope and instruments are then removed, and the incisions are closed with sutures. Sterile dressings are applied, secured, and an elastic bandage is used for compression.
2.3.3 Postoperative care
Rehabilitation exercises commence the day after surgery, focusing on knee flexion with slow and gentle movements aimed at achieving the maximum range of motion without emphasizing repetition. Outpatient follow-up and suture removal are scheduled for 10 days postoperatively to assess recovery progress.
2.4 Outcome assessments
All participants underwent assessments two weeks pre- and post-intervention. Baseline measurements encompassed age, gender, Body Mass Index (BMI), Kellgren-Lawrence grading, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Society Score for knee-specific (KSS_knee) and function-specific (KSS_function) parameters, and gait spatiotemporal parameters, including gait cycle time, stride length, walking speed, cadence, affected side stance phase time, affected side swing phase time, and double support phase time, as well as kinematic parameters such as the maximum and minimum flexion angles of the hip and knee joints.
The primary outcomes focused on gait parameters during walking before and after surgery, involving both spatiotemporal and kinematic aspects. Testing occurred in a designated, clean, and disturbance-free room. Participants donned form-fitting, non-black, and non-reflective attire to reduce capture errors. Two researchers (A and B) utilized the Odonate system to perform standardized gait assessments on all participants, capturing data for inter-rater reliability analysis. Participants walked at a self-selected, comfortable pace to ensure at least six successful trials were recorded. The Odonate system's analysis software processed the measured data to extract gait parameters, including the identification of gait cycle intervals, marking of gait events, and computation of gait metrics. Manual frame-by-frame review was conducted for gait event detection in each recorded trial. Kinematic parameters were determined and filtered through a fourth-order zero-phase 6 Hz Butterworth low-pass filter by the Odonate system.
The Odonate 3D motion capture system, developed by Shanghai Maver Medical Technology Co., Inc., integrates a mobile terminal equipped with dual depth cameras operating at a 30 Hz sampling frequency and a workstation that incorporates depth sensing, neural network technology, and millimetric point cloud analysis. This advanced system, featuring a binocular depth camera and artificial intelligence, automates the capture, analysis, and calculation of gait parameters. The analytical process includes1: capture, which involves reconstructing participants' 3D movement models based on depth perception2; segmentation, which leverages deep learning to automatically identify body segments3; registration, performing point cloud matching automatically with deep neural networks; and4 calculation, which computes both spatiotemporal and kinematic parameters8 (Fig. 2).
Secondary outcomes encompass the Western Ontario and McMaster Universities (WOMAC) Scale, which assesses the severity of osteoarthritis symptoms, and the Knee Society Score (KSS), a composite measure that includes both functional and clinical scores to evaluate the condition and treatment efficacy of knee joint disorders.
2.5 Sample size calculation and randomization
This randomized controlled trial is designed to evaluate the comparative efficacy of Acupotomy Arthroscope and Arthroscopic interventions on gait spatiotemporal and kinematic parameters, movement symptoms, and quality of life improvements in individuals with knee osteoarthritis. The study is conducted using an assessor-blind methodology. Eligible patients are randomly allocated to either the Acupotomy Arthroscope or Arthroscopic group utilizing the PLAN procedure in SAS 9.1 statistical software, with the sequence of randomization being generated and safeguarded by a designated individual, remaining concealed from the rest of the team.
Consistency in gait biomechanical assessments at both baseline and follow-up is ensured by a single, well-trained physician who remains uninformed of the treatment assignments. To guarantee the assessments' reliability and reproducibility, all research personnel have undergone standardized training.
Central adjudication of clinical outcomes and adverse events is performed by independent assessors who are blinded to treatment allocations and clinical specifics. Discrepancies between the central adjudicators and on-site evaluators are infrequent, with any disagreements resolved through collaborative discussion.
The study primarily focuses on the modifications in gait spatiotemporal and kinematic parameters following treatment. In the absence of analogous studies for reference, an exploratory approach using the double support phase time (s) from gait spatiotemporal parameters is adopted. Preliminary findings indicate that post-treatment improvements from baseline in the affected side stance phase time (s) are 0.2 (0.04) for one group and 0.18 (0.04) for the other. The study is powered for two-tailed testing with an alpha level of 0.05 and a power of 90 %. The total sample size, as calculated using G∗Power version 3.1.9.7, is 54. Accounting for an anticipated dropout rate of 20 %, a minimum of 38 participants is required per group.
2.6 Follow-up procedures
Patients undergo bedside assessments of their gait biomechanics both preoperatively and at the two-week postoperative mark.
2.7 Statistical analysis
Data were statistically analyzed using SPSS 26.0 for MAC. Continuous variables adhering to a normal distribution were expressed as the mean ± standard deviation (x ± s), with the Shapiro-Wilk test employed to assess data normality. Chi-square tests were conducted to evaluate baseline demographic data. Group differences were examined using independent t-tests, and analysis of covariance (ANCOVA) was applied to identify significant differences between groups. A threshold of P ≤ 0.05 was set to define statistical significance.
3 Results
3.1 Participants and baseline characteristics
Seventy-six participants recruited between June and August 2024 were enrolled and randomly divided into the Acupotomy Arthroscope (AA) group and the Arthroscopic group, each with 38 participants. Three participants in the Arthroscopic group withdrew from the study due to medical conditions not associated with knee osteoarthritis, leading to a dropout rate of 4 %. Analysis included all participants at the conclusion of the study (Fig. 3). No adverse events, such as falls, syncope, or sports injuries, were reported during the intervention period.
Baseline characteristics showed comparable demographics between groups (Table 2):
| Characteristic | Total (N = 73) | AA Group (n = 38) | Arthroscopy Group (n = 35) | p-value |
| Age (years) | 62.4 ± 7.1 | 62.9 ± 7.5 | 61.1 ± 5.8 | 0.268 |
| Weight (kg)a | 85.6 ± 15.5 | 83.1 ± 13.7 | 91.9 ± 18.2 | 0.017 |
| BMI (kg/m2) | 28.5 ± 4.1 | 28.1 ± 4.3 | 29.3 ± 3.8 | 0.189 |
| OA Laterality | 0.521 | |||
| - Bilateral | 59 (80.8 %) | 30 (78.9 %) | 29 (82.9 %) | |
| - Unilateral | 14 (19.2 %) | 8 (21.1 %) | 6 (17.1 %) | |
| K-L Grade | 0.132 | |||
| - Grade 2 | 27 (37.0 %) | 12 (31.6 %) | 15 (42.9 %) | |
| - Grade 3 | 37 (50.7 %) | 20 (52.6 %) | 17 (48.6 %) | |
| - Grade 4 | 9 (12.3 %) | 6 (15.8 %) | 3 (8.6 %) | |
| Sex | 0.153 | |||
| - Female | 45 (61.6 %) | 21 (55.3 %) | 24 (68.6 %) | |
| - Male | 28 (38.4 %) | 17 (44.7 %) | 11 (31.4 %) |
| Parameter | AA Group (n = 38) | Arthroscopy Group (n = 35) | ||
| Pre-op | Post-op Δ | Pre-op | Post-op Δ | |
| Stride Length (m)∗∗ | 0.60 ± 0.14 | +0.46 ± 0.08 | 0.55 ± 0.09 | +0.49 ± 0.06 |
| Walking Speed (m/s)∗∗ | 0.63 ± 0.20 | +0.91 ± 0.04 | 0.60 ± 0.14 | +0.97 ± 0.15 |
| Step Frequency (step/min)∗∗ | 61.8 ± 5.9 | +25.1 ± 1.3 | 64.7 ± 5.8 | +25.5 ± 2.0 |
| Gait Cycle Time (s)∗∗ | 1.33 ± 0.25 | −0.31 ± 0.10 | 1.28 ± 0.28 | −0.20 ± 0.12 |
| Parameter | AA Group Δ | Arthroscopy Group Δ | Cohen's d | p-value |
| Max Knee Flexion (°)∗∗ | +11.47 ± 0.31 | +10.14 ± 1.14 | 0.92 | <0.001 |
| Min Knee Flexion (°)∗∗ | −0.16 ± 0.02 | −0.24 ± 0.03 | 1.21 | <0.001 |
| Min Hip Flexion (°)∗ | −0.03 ± 1.14 | +0.88 ± 1.32 | 0.78 | 0.003 |
| Parameter | AA Group Δ | Arthroscopy Group Δ | Mean Difference (95 % CI) | p-value |
| Walking Speed (m/s)∗ | 0.91 ± 0.04 | 0.97 ± 0.15 | −0.06 (−0.11, −0.01) | 0.012 |
| Gait Cycle Time (s)∗∗ | −0.31 ± 0.10 | −0.20 ± 0.12 | −0.11 (−0.16, −0.06) | <0.001 |
| Swing Phase Time (s)∗∗ | −0.11 ± 0.04 | −0.05 ± 0.02 | −0.06 (−0.08, −0.04) | <0.001 |
| Scale | AA Group | Arthroscopy Group | ||
| Pre-op | Post-op Δ | Pre-op | Post-op Δ | |
| WOMAC∗∗ | 109.95 ± 5.23 | −36.95 ± 1.61 | 112.91 ± 6.14 | −29.94 ± 1.68 |
| KSS-knee∗∗ | 54.03 ± 4.23 | +21.92 ± 1.17 | 51.03 ± 3.42 | +26.94 ± 2.09 |
| KSS-function∗∗ | 48.00 ± 3.16 | +25.95 ± 0.77 | 50.00 ± 3.28 | +22.03 ± 1.15 |
| Parameter | AA Group Δ | Arthroscopy Group Δ | Cohen's d | p-value |
| WOMAC∗∗ | −36.95 ± 1.61 | −29.94 ± 1.68 | 1.78 | <0.001 |
| KSS-knee∗∗ | +21.92 ± 1.17 | +26.94 ± 2.09 | 0.92 | <0.001 |
| KSS-function∗∗ | +25.95 ± 0.77 | +22.03 ± 1.15 | 1.21 | <0.001 |
| Domain | AA Superiority | Arthroscopy Superiority | Key Findings (AA vs Control) |
| Gait Symmetry | ✔️ (p < 0.001) | – | 31 % greater improvement in cycle time |
| Knee Mobility | ✔️ (p < 0.001) | – | 13 % larger flexion improvement |
| Pain Relief | ✔️ (p < 0.001) | – | 23 % greater WOMAC reduction |
| Functional Recovery | ✔️ (p < 0.001) | – | 15 % higher KSS-function gains |
Weight difference: AA group 83.1 ± 13.7 kg vs Arthroscopy 91.9 ± 18.2 kg (p = 0.017)
K-L Grade distribution: Majority Grade 3 in both groups (52.6 % vs 48.6 %)
Gender ratio: Female predominance in Arthroscopy group (68.6 % vs 55.3 %)
3.2 Gait parameter improvements
3.2.1 Spatiotemporal outcomes
Both interventions significantly enhanced gait function (all p < 0.001) (Table 3):
Stride length: AA +76.7 % vs Arthroscopy +89.1 %
Walking speed: AA +144 % vs Arthroscopy +161.7 %
Key superiority of AA:
Greater gait cycle time reduction: 0.31 ± 0.10s vs −0.20 ± 0.12s (MD -0.11s, 95 %CI -0.16 to −0.06)
Larger swing phase improvement: Δ-0.11 ± 0.04s vs −0.05 ± 0.02s (p < 0.001, d = 1.21)
3.3 Kinematic performance
Critical findings:
Maximum knee flexion: AA achieved 11.47 ± 0.31° improvement vs 10.14 ± 1.14° (p < 0.001)
Minimum hip flexion: Differential change (−0.03 ± 1.14° vs +0.88 ± 1.32°, p = 0.003) suggesting distinct biomechanical mechanisms.
3.4 Intergroup gait comparisons
Key intergroup differences:
Walking speed: Arthroscopy group showed greater improvement (Δ+0.97 ± 0.15 vs +0.91 ± 0.04, p = 0.012)
Gait symmetry: AA reduced gait cycle time by 23.3 % vs 15.6 % in controls (p < 0.001)
3.5 Clinical outcomes
3.5.1 Intragroup improvements
Both groups exceeded minimal clinically important differences (MCID):
WOMAC: AA -33.6 % vs Arthroscopy −26.5 % (both p < 0.001)
KSS-function: AA +54.1 % vs Arthroscopy +44.1 %
3.5.2 Intergroup comparisons
Critical findings:
Pain relief: AA showed 23 % greater WOMAC reduction (p < 0.001, d = 1.78)
Functional recovery: AA achieved 15 % higher KSS-function gain (p < 0.001)
3.6 Comprehensive therapeutic profile
Key advantages of AA:
31 % greater gait symmetry improvement (p < 0.001)
13 % larger knee mobility restoration.
4 Discussion
Knee osteoarthritis, a prevalent joint condition, significantly impacts patients' walking patterns, particularly the stance and swing phases of their gait cycle.12 Patients often exhibit an extended stance phase to alleviate pressure on the affected knee, compensating for this with an increased double support phase to enhance stability. The swing phase is frequently shortened to minimize pain during the knee's motion, prompting a quicker transition through the affected leg and reducing the joint's range of motion.4
Stride length is typically reduced to decrease the load on the knee, subsequently affecting both stride length and frequency. To sustain their walking speed, patients may counteract this reduction by increasing their step frequency. Gait asymmetry may arise due to unilateral knee involvement, leading to discrepancies in stride and frequency between the legs.13 A painful gait may develop as patients seek to avoid excessive stress on the affected knee, characterized by decreased knee flexion and an expanded range of motion at the hip and ankle to provide compensation.14
The utilization of assistive devices such as crutches becomes essential for patients to support their body weight and alleviate knee joint stress. Changes in muscle strength and control due to arthritis necessitate reliance on alternative muscle groups for maintaining gait stability. A restricted range of motion in the knee joint can impact its flexion and extension throughout the gait cycle.15 Furthermore, gait stability is often compromised by pain and joint dysfunction, elevating the risk of falls.
At the two-week postoperative mark, a significant enhancement in stride length, walking velocity, and step frequency was observed in both patient groups compared to preoperative assessments, with statistically significant differences (P < 0.01). Concurrently, there was a significant reduction in the affected side's gait cycle duration, stance phase, swing phase, and double support phase, all demonstrating statistical significance (P < 0.01).
Upon intra-group comparison of kinematic parameters before and after treatment, a marked increase in the maximum knee flexion angle and a decrease in the minimum knee flexion angle were noted 15 days postoperatively, both statistically significant (P < 0.01). In contrast, no significant differences were observed in the hip joint's maximum and minimum flexion angles between the 15-day postoperative period and preoperative status (P > 0.05). Knee osteoarthritis patients typically present with diminished mobility of the knee joint,16 indicated by a reduced capacity for maximum knee flexion17 and an elevated minimum knee flexion angle.18
The Acupotomy Arthroscope effectively releases soft tissue adhesions and flushes the joint cavity, enhancing the joint's overall internal and external equilibrium. When integrated with subcutaneous release via probe needles, it delivers a holistic decompression effect across the joint, muscle, and subcutaneous layers, resulting in reduced inflammation and pain relief.19 The Acupotomy Arthroscope plays a significant role in alleviating the contracted state of the knee joint capsule, offering an indirect decompression effect on surrounding soft tissues, including the patellar ligament, the attachment of the quadriceps tendon to the patella, the medial and lateral collateral ligaments, and the attachment sites of the gastrocnemius tendon on the medial and lateral femoral condyles. Beyond this, the Acupotomy Arthroscope facilitates the removal of pro-inflammatory agents from the joint fluid through internal irrigation, thereby contributing to a healthier joint environment.20 Enhanced the internal fluid environment within the knee joint cavity and effectively broke the cycle of inflammatory reactions, thereby preventing the escalation of joint inflammation.21 Studies have reported a notable elevation in the plasma levels of miR-365 among patients with Knee Osteoarthritis (KOA), with the severity of their condition exhibiting an inverse correlation to the levels of miR-140, indicating a potential biomarker role in disease progression and severity assessment.22The Acupotomy Arthroscope effectively modulates inflammatory levels by regulating plasma concentrations of miR-140 and miR-365. This targeted adjustment leads to a significant improvement in patients' WOMAC scores, a key indicator of osteoarthritis symptoms and functionality, thereby optimizing treatment efficacy and enhancing the overall prognosis for patients with Knee Osteoarthritis.23
The Acupotomy Arthroscope and Arthroscopy are both capable of effectively lysing adhesions surrounding the joints in patients during surgery. Through the irrigation of the joint cavity to eliminate inflammatory mediators, they enhance joint mobility and range of motion. The artificial tract created during the surgical procedure serves to augment local blood perfusion, thereby promoting improved blood circulation and oxygenation of the tissues.24
In comparisons of inter-group changes in gait spatiotemporal parameters from baseline, the Acupotomy Arthroscope group demonstrated more significant enhancements in the affected side's gait cycle duration, stance phase, and swing phase times compared to the Arthroscopic group. However, the improvement in walking speed postoperatively was less pronounced in the Acupotomy Arthroscope group. The more notable improvements in gait parameters in the Acupotomy Arthroscope group are primarily due to the minimally invasive nature of the procedure, which allows for quicker recovery and favorable short-term results. The Arthroscopic group's better performance in postoperative walking speed improvement may be attributed to a more comprehensive release of affected tissues during surgery, leading to enhanced joint mobility.
Treatment with the Acupotomy Arthroscope effectively halts the progressive degeneration that is characteristic of the cruciate ligaments, particularly affecting their points of attachment. Additionally, it curbs the deterioration of proprioceptive receptors located at these attachment points, thereby preserving their function and integrity.25 The treatment suppresses the deterioration of proprioceptive capabilities. Additionally, Acupotomy Arthroscope therapy can not only improve but also potentially reverse the damage to chondrocyte structure and collagen fibers, essential for maintaining cartilage integrity. It promotes the relaxation of contracted soft tissues, facilitating the restoration of the joint's dynamic equilibrium. By eliminating mechanical impediments within the knee that obstruct functional recovery and alleviate pain, the therapy creates a conducive environment for cartilage repair and overall joint health.26 This approach restores the joint's dynamic balance. The Acupotomy Arthroscope directly addresses myofascial trigger points, leveraging its releasing capabilities to alleviate tension in the surrounding tissues, thereby reinforcing joint stability and enhancing the coordination of tendons.27 Consequently, this intervention results in improved postoperative gait parameters on the affected side, including the gait cycle time, stance phase duration, and swing phase duration, thereby enhancing the overall gait pattern of the patient.
In the comparative analysis of kinematic parameters relative to baseline, the Acupotomy Arthroscope group outperformed the Arthroscopic group in improving the minimum hip flexion angle postoperatively. However, no significant differences were observed between preoperative and postoperative minimum hip flexion angles within both groups. The Acupotomy Arthroscope group also demonstrated superior improvement in the maximum knee flexion angle postoperatively, yet inferior improvement in the minimum knee flexion angle. Intra-group comparisons revealed no significant postoperative improvements in either the minimum or maximum hip flexion angles. The superior improvement in the minimum hip flexion angle in the Acupotomy Arthroscope group may be attributed to the shorter recovery time and enhanced coordination between the knee and hip joints. The better performance in the maximum knee flexion angle in the Acupotomy Arthroscope group and the minimum knee flexion angle in the Arthroscopic group could be related to the specific sites, sequences, and methods of release employed in each surgical approach.
Both groups exhibited a significant reduction in the WOMAC score and a significant increase in KSS_knee and KSS_function scores postoperatively, indicating that both surgical methods effectively improve joint clinical symptoms. The Acupotomy Arthroscope group showed greater improvements in the WOMAC score and KSS_function score compared to the Arthroscopic group, while the KSS_knee score improvement was less pronounced. The WOMAC score and KSS_function score, which focus on clinical symptoms and daily activity function of the knee, showed better improvement in the Acupotomy Arthroscope group due to its less invasive nature and shorter recovery time. In contrast, the KSS_knee score, focusing on joint pain, mobility, stability, and range of motion limitations, showed better improvement in the Arthroscopic group, likely due to the more extensive release achieved during surgery.
Clinical gait analysis typically utilizes a three-dimensional motion capture system based on infrared photoelectric cells and reflective markers in a gait laboratory, which is considered the gold standard. However, this method is limited by spatial and cost constraints and requires skilled operators. Moreover, the need for subjects to expose their skin for marker placement can be inconvenient. Advances in sensor technology have introduced depth-based perception as a viable alternative for clinical gait analysis.
This study employed the Odonate gait analysis system, developed by Maver Medical, which utilizes depth cameras for intelligent gait assessment in clinical settings. Unlike traditional systems, Odonate does not require body markers and can be used in a compact space for efficient motion capture and gait analysis, reducing examination time and patient discomfort.
The study has several limitations, including the inability to achieve a double-blind design due to the open intervention nature. The results are specific to patients with moderate knee osteoarthritis, and the applicability to advanced stages is unknown. The short follow-up duration limits the assessment of medium and long-term effects. Additionally, the sample size is insufficient, and expanding the trial to include participants from other centers and regions would strengthen the findings. Future research should aim to increase the sample size and evaluate the long-term effects of Acupotomy Arthroscope on knee osteoarthritis patients.
In conclusion, both Acupotomy Arthroscope and Arthroscopic interventions significantly improve gait biomechanics and joint symptom scores. The Acupotomy Arthroscope showed superior improvement in gait spatiotemporal parameters and the minimum hip flexion angle, but inferior improvement in postoperative walking speed. It also demonstrated better improvement in the maximum knee flexion angle, while the Arthroscopic group showed better improvement in the minimum knee flexion angle. The Acupotomy Arthroscope provided more significant short-term improvements in knee joint clinical symptoms.
CRediT authorship contribution statement
Zichao Xiong: Investigation, Formal analysis, Funding acquisition, Conceptualization, Supervision, writing—reviewing & editing, Project administration, Data curation. Shaodan Cheng: Methodology, Investigation, Formal analysis, Validation. Cheng Ge: Methodology, Investigation, Formal analysis, Validation. Yang Zhang: Methodology, Investigation, Formal analysis, Validation. Shihui Wang: Methodology, Investigation, Formal analysis, Writing – original draft. Yunwen Gao: Investigation, Formal analysis, Funding acquisition, Conceptualization, Supervision, writing—reviewing & editing, Project administration, Data curation. Yinghui Ma: Methodology, Investigation, Formal analysis, Validation, Sichen PENG, Methodology, Investigation, Formal analysis, Writing – original draft.
Availability of data and materials
The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Declarations
The trial is registered with the Chinese Clinical Trial Registry under the number ChiCTR2400083232 and has received ethical approval from the Guanghua Hospital of Integrated Traditional Chinese and Western Medicine in Shanghai (Ethics No.: 2024-K-48).
Ethics approval and consent to participate
The present study was approved by the Guanghua Hospital of Integrated Traditional Chinese and Western Medicine in Shanghai.The reference number: 2024-K-48.
Consent for publication
Not applicable.
Funding
This study was supported by the Science and Technology Commission of Shanghai Municipality [No. 19401935000, No. 20Y21901600]; the Shanghai "14th Five-Year Plan" Chinese Medicine Specialty Construction Project (No. ZYTSZK2-2); the Science and Technology Commission of Changning District, Shanghai (No. CNKW20185Y12); the Shanghai Changning District Medical Innovation Talent Base Project (No. RCJD2022S03); the Shanghai Changning District Famous Chinese Medicine Construction Project (No. CNMZY-2021013); and the Shanghai Changning District Young Chinese Medicine Doctor Training Program (No. 2021CNQNZY002).
References
- Association of knee injuries with accelerated knee osteoarthritis progression: data from the Osteoarthritis Initiative. Arthritis Care Res. 2014 Nov;66(11):1673-1679.
- [Google Scholar]
- The effect of osteoarthritis definition on prevalence and incidence estimates: a systematic review. Osteoarthr Cartil. 2011 Nov;19(11):1270-1285.
- [Google Scholar]
- The association between knee joint biomechanics and neuromuscular control and moderate knee osteoarthritis radiographic and pain severity. Osteoarthr Cartil. 2011 Feb;19(2):186-193.
- [Google Scholar]
- Gait modification strategies for altering medial knee joint load: a systematic review. Arthritis Care Res. 2011 Mar;63(3):405-426.
- [Google Scholar]
- Timely application of integrated traditional Chinese and Western medicine methods to improve clinical efficacy in knee osteoarthritis: interpretation of the "Traditional Chinese Medicine Diagnosis and Treatment Guidelines for Knee Osteoarthritis. Chinese Journal of Orthopedics and Traumatology. 2020;vol. 3:1-2.
- [Google Scholar]
- Interpretation of the 2018 Edition of the Osteoarthritis Diagnosis and Treatment Guidelines. 2018;vol. 11:1241-1243.
- [Google Scholar]
- The validity and reliability of a new intelligent three-dimensional gait analysis system in healthy subjects and patients with post-stroke. Sensors (Basel). 2022 Dec 2;22(23):9425.
- [Google Scholar]
- Development and evaluation of a tool for the assessment of footwear characteristics. J Foot Ankle Res. 2009 Apr 23;2:10.
- [Google Scholar]
- Differences in gait pattern parameters between medial and anterior knee pain in patients with osteoarthritis of the knee. Clin Biomech (Bristol, Avon).. 2012 Jul;27(6):584-587.
- [Google Scholar]
- The relative timing of VMO and VL in the aetiology of anterior knee pain: a systematic review and meta-analysis. BMC Muscoskelet Disord. 2008 May 1;9:64.
- [Google Scholar]
- Arthroscopic surgery for degenerative knee: systematic review and meta-analysis of benefits and harms. BMJ. 2015 Jun 16;350
- [Google Scholar]
- Valgus malalignment is a risk factor for lateral knee osteoarthritis incidence and progression: findings from the Multicenter Osteoarthritis Study and the Osteoarthritis Initiative. Arthritis Rheum. 2013 Feb;65(2):355-362.
- [Google Scholar]
- Effect of thigh strength on incident radiographic and symptomatic knee osteoarthritis in a longitudinal cohort. Arthritis Rheum. 2009 Sep 15;61(9):1210-1217.
- [Google Scholar]
- Asymmetric loading and bone mineral density at the asymptomatic knees of patients with unilateral hip osteoarthritis. Arthritis Rheum. 2011 Dec;63(12):3853-3858.
- [Google Scholar]