OBJECTIVE: To investigate the effectiveness and safety of simultaneous bilateral total knee athroplasty (SB-TKA) for the treatment of patients aged 65 years and younger with bilateral knee osteoarthritis (KOA) by comparing with patients undergoing unilateral total knee arthroplasty (U-TKA). METHODS: A clinical data of patients, who underwent primary TKA for KOA and met the selection criteria between June 2019 and July 2023, was retrospectively analyzed, including 181 patients in the U-TKA group and 52 patients in the SB-TKA group. The baseline data of age, gender, disease duration, body mass index, and preoperative hemoglobin (Hb), knee range of motion (ROM), Oxford knee score (OKS), and visual analogue scale (VAS) score for pain were compared between the two groups, with no significant difference ( P>0.05). The operation time, postoperative hospital stay, and all complications related to knee arthroplasty were recorded. Hb was measured at 2 days after operation and the difference between pre- and post-operation was calculated. The knee function and pain were evaluated by using ROM, OKS score, and VAS score and compared between the two groups. RESULTS: The operation time and postoperative hospital stay duration were significantly shorter in the U-TKA group than in the SB-TKA group ( P<0.05). The difference of Hb was significantly lower in the U-TKA group ( P<0.05). All patients were followed up 12-61 months (mean, 37.2 months). There was no significant difference in follow-up time between the two groups ( P>0.05). At last follow-up, the ROM, OKS score, and VAS score of both groups were better than the preoperative ones, and the differences were significant ( P<0.05); there were significant differences between the two groups in the ROM and OKS score ( P<0.05), while no significant difference was found in the VAS score ( P>0.05). Mild complications were observed in 31 cases (17.13%) and severe complications in 3 cases (1.66%) in the U-TKA group, while mild complications were observed in 14 cases (26.92%) in the SB-TKA group, and no severe complication occurred. There was no significant difference in the incidences of mild and severe complications between the two groups ( P>0.05). CONCLUSION In patients aged 65 years and younger with bilateral KOA, knee function and mobility can significantly improved when treated by SB-TKA. While patients had lower postoperative knee mobility and function scores compared with U-TKA, there was no significant difference in pain scores or overall incidence of complication. Strict patient selection and scientific perioperative management are important to achieve good effectiveness after operation in patients with SB-TKA.
Humans ; Arthroplasty, Replacement, Knee/adverse effects* ; Male ; Female ; Retrospective Studies ; Osteoarthritis, Knee/physiopathology* ; Range of Motion, Articular ; Treatment Outcome ; Middle Aged ; Operative Time ; Length of Stay ; Knee Joint/physiopathology* ; Pain Measurement ; Postoperative Complications/epidemiology* ; Aged

OBJECTIVE: To investigate the load distribution on the more painful and less painful limbs in patients with mild-to-moderate and severe bilateral knee osteoarthritis (KOA) and explore the compensatory mechanisms in both limbs among bilateral KOA patients with different severity levels. METHODS: A total of 113 participants were enrolled between July 2022 and September 2023. This cohort comprised 43 patients with mild-to-moderate bilateral KOA (Kellgren-Lawrence grade 2-3), 43 patients with severe bilateral KOA (Kellgren-Lawrence grade 4), and 27 healthy volunteers (healthy control group). The visual analogue scale (VAS) score for pain, the Hospital for Special Surgery (HSS) score, passive knee range of motion (ROM), and hip-knee-ankle angle (HKA) were used to assess walking pain intensity, joint function, and lower limb alignment in KOA patients, respectively. Motion trajectories of reflective markers and ground reaction force data during walking were captured using a gait analysis system. Musculoskeletal modeling was then employed to calculate biomechanical parameters, including the peak knee adduction moment (KAM), KAM impulse, peak joint contact force (JCF), and peak medial/lateral contact forces (MCF/LCF). Statistical analyses were performed to compare differences in clinical and gait parameters between bilateral limbs. Additionally, one-dimensional statistical parametric mapping was utilized to analyze temporal gait data. RESULTS: Mild-to-moderate KOA patients showed the significantly higher HSS score (67.7±7.9) than severe KOA patients (51.9±8.9; t=8.747, P<0.001). The more painful limb in all KOA patients exhibited significantly greater HKA and higher VAS scores compared to the less painful limb ( P<0.05). While bilateral knee ROM did not differ significantly in mild-to-moderate KOA patients ( P>0.05), the severe KOA patients had significantly reduced ROM in the more painful limb versus the less painful limb ( P<0.05). Healthy controls showed no significant bilateral difference in any biomechanical parameters ( P>0.05). All KOA patients demonstrated longer stance time on the less painful limb ( P<0.05). Critically, severe KOA patients exhibited significantly higher peak KAM, KAM impulse, and peak MCF in the more painful limb ( P<0.05), while mild-to-moderate KOA patients showed the opposite pattern with lower peak KAM and KAM impulse in the more painful limb ( P<0.05) and a similar trend for peak MCF. CONCLUSION Patients with mild-to-moderate KOA effectively reduce load on the more painful limb through compensatory mechanisms in the less painful limb. Conversely, severe bilateral varus deformities in advanced KOA patients nullify compensatory capacity in the less painful limb, paradoxically increasing load on the more painful limb. This dichotomy necessitates personalized management strategies tailored to disease severity.
Humans ; Osteoarthritis, Knee/physiopathology* ; Range of Motion, Articular ; Male ; Female ; Middle Aged ; Biomechanical Phenomena ; Knee Joint/physiopathology* ; Pain Measurement ; Severity of Illness Index ; Aged ; Gait/physiology* ; Walking/physiology* ; Case-Control Studies ; Adult ; Weight-Bearing

OBJECTIVE: To assess the effectiveness of bone acupuncture in improving pain and function in degenerative lumbar spinal stenosis (DLSS) and compare it with Jiaji acupuncture. METHODS: From January to December 2023, 80 DLSS patients were treated with acupuncture and divided into bone acupuncture and Jiaji acupuncture groups. Among them, 40 patients in the bone acupuncture group included 15 males and 25 females, with a mean age of (60.60±6.98) years old;anthor 40 patients in the Jiaji acupuncture group included 16 males and 24 females, with a mean age of (61.48±9.55) years old. The Roland Morris disability questionnaire(RMDQ), walking distance, visual analogue scale(VAS), and the MOS item short from health survey(SF-36) of two groups at baseline, 2 weeks, 4 weeks, and 12 weeks post-treatment were compared. RESULTS: Eighty patients were followed up for 3 to 5 months with an average of (3.62±0.59) months. There was no significant differences in general data and the scores before treatment between two groups(P>0.05). The RMDQ scores in both groups decreased significantly at 2, 4 and 12 weeks after treatment compared with before treatment(P<0.05), at each time point after treatment, the decrease was more significant in the bone acupuncture group than in the Jiaji acupuncture group(P<0.05). The VAS of waist and leg in both groups was significantly lower at 2, 4 and 12 weeks after treatment that before treatment(P<0.05). At all time points after treatment, the waist VAS in the bone acupuncture group was reduced more significant than in the Jiaji acupuncture group(P<0.05);there was no significant difference in leg VAS at 2 and 12 weeks after treatment between two groups(P>0.05), the improvement was more significant in the bone acupuncture group in the 4 weeks after treatment than in the Jiaji acupuncture group. The SF-36 scores in both groups were significantly higher at 2, 4, and 12 weeks after treatment than before treatment(P<0.05);the SF-36 score raised more significant in the bone acupuncture group than in the Jiaji acupunture group(P<0.05). No significant difference in the walking distance between two groups at 2 weeks after treatment(P>0.05);the walking distance in the bone acupuncture group was significantly higher than that in the Jiaji acupuncture group at 4 and 12 weeks after treatment(P<0.05). CONCLUSION Bone-penetrating acupuncture moderately improves functional impairment, pain, and quality of life in patients with DLSS, showing better efficacy than Jiaji acupuncture.
Humans ; Female ; Male ; Middle Aged ; Acupuncture Therapy/methods* ; Spinal Stenosis/physiopathology* ; Aged ; Lumbar Vertebrae/physiopathology* ; Pain Management

OBJECTIVE: To explore the optimal vertical traction weight, clinical efficacy, and safety of bidirectional cervical traction in the treatment of cervical kyphosis. METHODS: A total of 130 patients with neck pain and cervical kyphosis confirmed by cervical DR who visited the hospital from April 2023 to April 2024 were enrolled. They were divided into 4 groups according to the vertical traction weight accounting for 5%, 10%, 15%, and 20% of their body weight, respectively. The 5% body weight traction group included 33 cases (13 males and 20 females) with an average age of (34.00±10.58) years old;the 10% body weight traction group included 35 cases (17 males and 18 females) with an average age of (32.23±8.39) years old;the 15% body weight traction group included 32 cases (14 males and 18 females) with an average age of (33.88±10.09) years old;the 20% body weight traction group included 30 cases (11 males and 19 females) with an average age of (36.20±9.13) years old. Each group received treatment for 2 weeks. The visual analogue scale (VAS) score, neck disability index (NDI), and C₂-C₇ Cobb angle on cervical lateral X-ray films before and after treatment were recorded to evaluate the clinical efficacy of the 4 groups. RESULTS: When the traction weight was 10% and 15% of body weight, the pain VAS and NDI were significantly improved, and the C₂-C₇ Cobb angle increased, with statistically significant differences (P<0.05), and no adverse reactions occurred. However, in the 5% body weight group, the above indicators showed no significant changes, with no statistically significant differences (P>0.05). In the 20% body weight group, some patients could not tolerate the treatment, and adverse reactions such as dizziness, nausea, and aggravated neck pain occurred. CONCLUSION The optimal vertical traction weight of bidirectional cervical traction for cervical kyphosis is 10%-15% of body weight, which can effectively improve neck pain and cervical function, increase the C₂-C₇ Cobb angle of the cervical spine, with high safety, and is worthy of promotion and application.
Humans ; Male ; Female ; Traction/methods* ; Kyphosis/physiopathology* ; Adult ; Cervical Vertebrae/physiopathology* ; Middle Aged ; Neck Pain ; Young Adult

OBJECTIVE: To elucidate how spinal manipulative therapy (SMT) exerts its analgesic effects through regulating brain function in lumbar disc herniation (LDH) patients by utilizing resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: From September 2021 to September 2023, we enrolled LDH patients (LDH group, n=31) and age- and sex-matched healthy controls (HCs, n=28). LDH group underwent rs-fMRI at 2 distinct time points (TPs): prior to the initiation of SMT (TP1) and subsequent to the completion of the SMT sessions (TP2). SMT was administered once every other day for 30 min per session, totally 14 treatment sessions over a span of 4 weeks. HCs did not receive SMT treatment and underwent only one fMRI scan. Additionally, participants in LDH group completed clinical questionnaires on pain using the Visual Analog Scale (VAS) and the Japanese Orthopedic Association (JOA) score, whereas HCs did not undergo clinical scale assessments. The effects on the brain were jointly characterized using the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo). Correlation analyses were conducted between specific brain regions and clinical scales. RESULTS: Following SMT treatment, pain symptoms in LDH patients were notably alleviated and accompanied by evident activation of effects in the brain. In comparison to TP1, TP2 exhibited the most significant increase in ALFF values for Temporal_Sup_R and the most notable decrease in ALFF values for Paracentral_Lobule_L (voxelwise P<0.005; clusters >30; FDR correction). Additionally, the most substantial enhancement in ReHo values was observed for the Cuneus_R, while the most prominent reduction was noted for the Olfactory_R (voxelwise P<0.005; clusters >30; FDR correction). Moreover, a comparative analysis revealed that, in contrast to HCs, LDH patients at TP1 exhibited the most significant increase in ALFF values for Temporal_Pole_Sup_L and the most notable decrease in ALFF values for Frontal_Mid_L (voxelwise P<0.005; clusters >30; FDR correction). Furthermore, the most significant enhancement in ReHo values was observed for Postcentral_L, while the most prominent reduction was identified for ParaHippocampal_L (voxelwise P<0.005; clusters >30; FDR correction). Notably, correlation analysis with clinical scales revealed a robust positive correlation between the Cuneus_R score and the rate of change in the VAS score (r=0.9333, P<0.0001). CONCLUSIONS Long-term chronic lower back pain in patients with LDH manifests significant activation of the "AUN-DMN-S1-SAN" neural circuitry. The visual network, represented by the Cuneus_R, is highly likely to be a key brain network in which the analgesic efficacy of SMT becomes effective in treating LDH patients. (Trial registration No. NCT06277739).
Humans ; Magnetic Resonance Imaging ; Intervertebral Disc Displacement/diagnostic imaging* ; Male ; Female ; Brain/diagnostic imaging* ; Adult ; Manipulation, Spinal/methods* ; Middle Aged ; Lumbar Vertebrae/physiopathology* ; Pain Management ; Rest ; Case-Control Studies

Chronic pain, a prevalent chronic disease, frequently manifests not only in physical symptoms but also in cognitive impairment, which seriously affects patients' quality of life. Interneurons are multipolar neurons, most of which are inhibitory, serving as crucial connectors within neural networks. They play key roles in signal transmission and fine-tuning of neural activity. In recent years, growing evidence has shown that interneurons are involved in the development of chronic pain and its associated cognitive dysfunction. Investigating the relationship between interneuron dysfunction and chronic pain-related cognitive impairment is of great significance, offering new potential targets and insights for the development of novel therapeutic approaches.
Interneurons/physiology* ; Humans ; Chronic Pain/complications* ; Cognitive Dysfunction/physiopathology* ; Cognition Disorders/physiopathology* ; Animals

The pain-evoked potential electroencephalogram (EEG) is an effective electrophysiological indicator for pain assessment, yet its extraction is challenging due to interference from background activity and involuntary blinks. Although existing blink artifact-removal methods show efficacy, they face limitations such as the need for reference signals, neglect of individual differences, and reliance on user input, hindering their practical application in clinical pain assessments. In this paper, we propose a novel framework applying adaptive quadrature mirror filter banks (AQMFB) with discrete wavelet transform (DWT) to remove blink artifacts in pain EEG. Unlike traditional DWT methods that apply fixed wavelets across subjects, our method adapts wavelet construction based on the characteristics of EEG. Experimental results demonstrate that AQMFB-DWT outperforms four leading methods in removing blink artifacts with minimal distortion of pain information, all within an acceptable processing time. This technique is a valuable preprocessing step for enhancing the extraction of pain-evoked potentials.
Humans ; Artifacts ; Blinking/physiology* ; Electroencephalography/methods* ; Pain/diagnosis* ; Male ; Wavelet Analysis ; Adult ; Female ; Evoked Potentials/physiology* ; Young Adult ; Brain/physiopathology* ; Pain Measurement/methods* ; Signal Processing, Computer-Assisted

Chronic pain, frequently comorbid with neuropsychiatric disorders, significantly impairs patients' quality of life and functional capacity. Accumulating evidence implicates the chemokine CCL2 and its receptor CCR2 as key players in chronic pain pathogenesis. This review examines the regulatory mechanisms of the CCL2/CCR2 axis in chronic pain processing at three hierarchical levels: (1) Peripheral Sensitization: CCL2/CCR2 modulates TRPV1, Nav1.8, and HCN2 channels to increase neuronal excitability and CGRP signaling and calcium-dependent exocytosis in peripheral nociceptors to transmit pain. (2) Spinal Cord Central Sensitization: CCL2/CCR2 contributes to NMDAR-dependent plasticity, glial activation, GABAergic disinhibition, and opioid receptor desensitization. (3) Supraspinal Central Networks: CCL2/CCR2 signaling axis mediates the comorbidity mechanisms of pain with anxiety and cognitive impairment within brain regions, including the ACC, CeA, NAc, and hippocampus, and it also increases pain sensitization through the descending facilitation system. Current CCL2/CCR2-targeted therapeutic strategies and their development status are discussed, highlighting novel avenues for chronic pain management.
Humans ; Chronic Pain/physiopathology* ; Animals ; Neuroglia/metabolism* ; Chemokine CCL2/metabolism* ; Receptors, CCR2/metabolism*

Temporomandibular joint osteoarthritis (TMJ-OA) is a common disease often accompanied by pain, seriously affecting physical and mental health of patients. Abnormal innervation at the osteochondral junction has been considered as a predominant origin of arthralgia, while the specific mechanism mediating pain remains unclear. To investigate the underlying mechanism of TMJ-OA pain, an abnormal joint loading model was used to induce TMJ-OA pain. We found that during the development of TMJ-OA, the increased innervation of sympathetic nerve of subchondral bone precedes that of sensory nerves. Furthermore, these two types of nerves are spatially closely associated. Additionally, it was discovered that activation of sympathetic neural signals promotes osteoarthritic pain in mice, whereas blocking these signals effectively alleviates pain. In vitro experiments also confirmed that norepinephrine released by sympathetic neurons promotes the activation and axonal growth of sensory neurons. Moreover, we also discovered that through releasing norepinephrine, regional sympathetic nerves of subchondral bone were found to regulate growth and activation of local sensory nerves synergistically with other pain regulators. This study identified the role of regional sympathetic nerves in mediating pain in TMJ-OA. It sheds light on a new mechanism of abnormal innervation at the osteochondral junction and the regional crosstalk between peripheral nerves, providing a potential target for treating TMJ-OA pain.
Animals ; Osteoarthritis/physiopathology* ; Mice ; Sympathetic Nervous System/physiopathology* ; Temporomandibular Joint Disorders/physiopathology* ; Arthralgia ; Sensory Receptor Cells ; Disease Models, Animal ; Norepinephrine ; Male ; Temporomandibular Joint/physiopathology* ; Pain Measurement

OBJECTIVE: To screen the population for acupuncture treatment of neck pain, using functional magnetic resonance imaging (fMRI) technology and based on machine learning algorithms. METHODS: Eighty patients with neck pain were recruited. Using FPX25 handheld pressure algometer, the tender points were detected in the areas with high-frequent onset of neck pain and high degree of acupoint sensitization. Acupuncture was delivered at 4 tender points with the lowest pain threshold, once every two days; and the treatment was given 3 times a week and for 2 consecutive weeks. The amplitude of low-frequency fluctuation (ALFF) of the brain before treatment was taken as a predictive feature to construct support vector machine (SVM), logistic regression (LR), and K-nearest neighbors (KNN) models to predict the responses of neck pain patients to acupuncture treatment. A longitudinal analysis of the ALFF features was performed before and after treatment to reveal the potential biological markers of the reactivity to the acupuncture therapy. RESULTS: The SVM model could successfully distinguish high responders (48 cases) and low responders (32 cases) to acupuncture treatment, and its accuracy rate reached 82.5%. Based on the SVM model, the ALFF values of 4 brain regions were identified as the consistent predictive features, including the right middle temporal gyrus, the right superior occipital gyrus, and the bilateral posterior cingulate gyrus. In the patients with high acupuncture response, the ALFF value in the left posterior cingulate gyrus decreased after treatment (P<0.05), whereas in the patients with low acupuncture response, the ALFF value in the right superior occipital gyrus increased after treatment (P<0.01). The longitudinal functional connectivity (FC) analysis found that compared with those before treatment, the high responders showed the enhanced FC after treatment between the left posterior cingulate gyrus and various regions, including the bilateral Crus1 of the cerebellum, the right insula, the bilateral angular gyrus, the left medial superior frontal gyrus, and the left middle cingulate gyrus (GRF: corrected, voxel level: P<0.05, mass level: P<0.05). In contrast, the low responders exhibited the enhanced FC between the left posterior cingulate gyrus and the left Crus2 of the cerebellum, the left middle temporal gyrus, the right posterior cingulate gyrus, and the left angular gyrus; besides, FC was reduced in low responders between the left posterior cingulate gyrus and the right supramarginal gyrus (GRF: corrected, voxel level: P<0.05, mass level: P<0.05). CONCLUSION This study validates the practicality of pre-treatment ALFF feature prediction for acupuncture efficacy on neck pain. The therapeutic effect of acupuncture on neck pain is potentially associated with its impact on the default mode network, and then, alter the pain perception and emotional regulation.
Humans ; Neck Pain/physiopathology* ; Acupuncture Therapy ; Female ; Male ; Adult ; Middle Aged ; Machine Learning ; Magnetic Resonance Imaging ; Young Adult ; Brain/physiopathology* ; Acupuncture Points ; Aged