Aberrant activation of latent transforming growth factor-β initiates the onset of temporomandibular joint osteoarthritis

There is currently no effective medical treatment for temporomandibular joint osteoarthritis(TMJ-OA) due to a limited understanding of its pathogenesis. This study was undertaken to investigate the key role of transforming growth factor-β(TGF-β)signalling in the cartilage and subchondral bone of the TMJ using a temporomandibular joint disorder(TMD) rat model, an ageing mouse model and a Camurati–Engelmann disease(CED) mouse model. In the three animal models, the subchondral bone phenotypes in the mandibular condyles were evaluated by μCT, and changes in TMJ condyles were examined by TRAP staining and immunohistochemical analysis of Osterix and p-Smad2/3. Condyle degradation was confirmed by Safranin O staining, the Mankin and OARSI scoring systems and type X collagen(Col X), p-Smad2/3 a and Osterix immunohistochemical analyses. We found apparent histological phenotypes of TMJ-OA in the TMD, ageing and CED animal models, with abnormal activation of TGF-βsignalling in the condylar cartilage and subchondral bone. Moreover, inhibition of TGF-β receptor I attenuated TMJ-OA progression in the TMD models. Therefore, aberrant activation of TGF-β signalling could be a key player in TMJ-OA development.

Association between facet joint osteoarthritis and the Oswestry Disability Index

AIM:To investigate the correlation of facet joint osteoarthritis(FJOA) at lumbar levels L4/L5 and L5/S1 and the Oswestry Disability Index(ODI).METHODS:The study involved lumbar MRIs of 591 patients with a mean age of 47.3 years.The MRIs of the lumbar spine were performed on a 1.5 Tesla scanner(Magnetom Avanto,Siemens AG,Erlangen,Germany) using a dedicated receive only spine coil.After initial blinding,each dataset was evaluated by 2 board certified radiologist with more than 5 years experience in musculoskeletal imaging.In total 2364 facet joints were graded.Degenerative changes of the facet joints were evaluated according to the 4-point scale as proposed by Weishaupt et al Functional status was assessed using the ODI.The index is scored from 0 to 100 and interpreted as follows:0%-20%,minimaldisability; 20%-40%,moderate disability; 40%-60%,severe disability; 60%-80%,crippled; 80%-100%,patients are bedbound.Spearman’s coefficient of rank correlation was used for statistical analysis,with significance set at P 【 0.05.RESULTS:In total 2364 facet joints at lumbar levels L4/5 and L5/S1 were analysed in 591 individuals.FJOA was present in 97%(L4/L5) and 98%(L5/S1).At level L4/5(left/right) 17/15(2.9%/2.5%) were described as grade 0,146/147(24.7%/24.9%) as grade 1,290/302(49.1%/51.1%) as grade 2 and 138/127(23.4%/21.5%) as grade 3.At level L5/S1(left/right) 10/11(1.7%/1.9%) were described as grade 0,136/136(23.0%/23.0%) as grade 1,318/325(53.8%/55.0%) as grade 2 and 127/119(21.5%/20.1%) as grade 3.Regarding the ODI scores,patients’ disability had a minimum of 0% and a maximum of 91.11% with an arithmetic mean of 32.77% ± 17.02%.The majority of patients(48.39%) had moderate functional disability(21%-40%).There was no significant correlation between FJOA and ODI on both sides of lumbar level L4/5 and on the left side of lumbar level L5/S1.A weak positive correlation was evaluated between ODI and FJOA on the right side of lumbar level L5/S1.CONCLUSION:The missing correlation of FJOA and ODI confirms our clinical experience that imaging alone is an insufficient approach explaining low back pain.Clinical correlation is imperative for an adequate diagnostic advance in patients with low back pain.

Treatment of condylar osteophyte in temporomandibular joint osteoarthritis with muscle balance occlusal splint and long-term follow-up:A case report

BACKGROUND Condylar osteophytes,a remodeling form of temporomandibular joint osteoarthritis(TMJ OA),mainly manifest as marginal angular outgrowths of the condyle.Previous researchers have advocated surgical removal of condylar osteophytes.Reports on the effect of occlusal splint on TMJ OA patients’joints have mostly focused on treatment with this splint,which can reduce the absorption of the affected condyle and promote repair and regeneration.However,the effect of the splint on the dissolution of condylar osteophytes has not yet been reported.CASE SUMMARY A 68-year-old female patient suffered from occlusal discomfort with left facial pain for 2 years.Cone beam computed tomography showed a rare osteophyte on top of her left condyle.She was finally diagnosed with TMJ OA.The patient refused surgical treatment and received conservative treatment with a muscle balance occlusal splint.The pain experienced by the patient on the left side of her face was relieved,and her chewing ability recovered after treatment.The osteophyte dissolved,and the condylar cortex remained stable during long-term follow-up observations.CONCLUSION The muscle balance occlusal splint could be a noninvasive means of treating condylar osteophytes in TMJ OA patients.

Poly(p-coumaric acid)nanoparticles alleviate temporomandibular joint osteoarthritis by inhibiting chondrocyte ferroptosis

Oxidative stress and inflammation are key drivers of osteoarthritis(OA)pathogenesis and disease progression.Herein we report the synthesis of poly(p-coumaric)nanoparticles(PCA NPs)from p-courmaic acid(p-CA),a naturally occurring phytophenolic acid,to be a multifunctional and drug-free therapeutic for temporomandibular joint osteoarthritis(TMJOA).Compared to hyaluronic acid(HA)that is clinically given as viscosupplementation,PCA NPs exhibited long-term efficacy,superior anti-oxidant and anti-inflammatory properties in alleviating TMJOA and repairing the TMJ cartilage and subchondral bone in a rat model of TMJOA.Notably,TMJ repair mediated by PCA NPs could be attributed to their anti-oxidant and anti-inflammatory properties in enhancing cell proliferation and matrix synthesis,while reducing inflammation,oxidative stress,matrix degradation,and chondrocyte ferroptosis.Overall,our study demonstrates a multifunctional nanoparticle,synthesized from natural p-coumaric acid,that is stable and possess potent antioxidant,anti-inflammatory properties and ferroptosis inhibition,beneficial for treatment of TMJOA.

Does therapist's attitude affect clinical outcome of lumbar facet joint injections?

AIM: To investigate if the clinical outcome of intraarticular lumbar facet joint injections is affected by the therapist's attitude. METHODS: A total of 40 patients with facet jointassociated chronic low back pain were randomly divided into two groups. All patients received computed tomography-guided, monosegmental intra-articular facet joint injections. Following the therapeutic procedure, the patients of the experimental group(EG) held a conversation with the radiologist in a comfortable atmosphere. During the dialog, the patients were encouraged to ask questions and were shown four images. The patients of the control group(CG) left the clinic without any further contact with the radiologist. Outcome was assessed using a pain-based Verbal Numeric Scale at baseline, at 1 wk and at 1, 3, and 6 mo after first treatment. RESULTS: The patient demographics showed no differences between the groups. The patients of the EG received 57 interventional procedures in total, while the patients of the CG received 70 interventional procedures. In both groups, the pain scores decreased significantly over the entire observation period. Compared to the CG, the EG showed a statistically significant reduction of pain at 1 wk and 1 mo post-treatment, while at 3 and 6 mo after treatment, there were no significant differences between both groups. CONCLUSION: Our results show a significant effect on pain relief during the early post-interventional period in the EG as compared to the CG. The basic principle behind the higher efficacy might be the phenomenon of hetero-suggestion.

Magnetic resonance imaging-based interpretation of degenerative changes in the lower lumbar segments and therapeutic consequences

Intervertebral disc degeneration and facet joint osteoarthritis of the lumbar spine are, among others, wellknown as a cause of low back and lower extremity pain. Together with their secondary disorders they set a big burden on health care systems and economics worldwide. Despite modern imaging modalities, such as magnetic resonance imaging, for a large proportion of patients with low back pain(LBP) it remains difficult to provide a specific diagnosis. The fact that nearly all the lumbar structures are possible sources of LBP, may serve as a possible explanation. Furthermore, our clinical experience confirms, that imaging alone is not a sufficient approach explaining LBP. Here, the Oswestry Disability Index, as the most commonly used measure to quantify disability for LBP, may serve as an easy-toapply questionnaire to evaluate the patient's ability to cope with everyday life. For therapeutic purposes, among the different options, the lumbar facet joint intraarticular injection of corticosteroids in combination with an anaesthetic solution is one of the most frequently performed interventional procedures. Although widely used the clinical benefit of intra-articular steroid injections remains controversial. Therefore, prior to therapy, standardized diagnostic algorithms for an accurate assessment, classification and correlation of degenerative changes of the lumbar spine are needed.

Patellofemoral MRI Alterations Following Single Bundle ACL Reconstruction with Hamstring Autografts Are Associated with Quadriceps Femoris Atrophy

High incidence of patellofemoral pain and patellofemoral joint osteoarthritis was found following anterior cruciate ligament(ACL)reconstruction.The unstability of patellofemoral joint might be an important contribution factor.This study was designed to define the relationship between the unstability of patellofemoral joint and quadriceps femoris atrophy.Twenty patients underwent MRI scan before ACL reconstruction and every two weeks after surgery,until 12 weeks.The merchant’s patellar congruence angle,lateral inclination angle,and quadriceps femoris muscle cross-sectional area were measured and the relationship between the changes of angles and the ratio of quadriceps femoris atrophy was studied by multiple regression analysis.Significant quadriceps femoris atrophy was observed after ACL reconstruction during the follow-up period of 12 weeks.The merchant’s patellar congruence angle and lateral inclination angle significantly changed after surgery.The alterations of the merchant’s patellar congruence angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=-5.76)and vastus lateralis(coefficient=8.35)during the follow-up period of 12 weeks.The alterations of lateral inclination angle were significantly correlated with the atrophy ratio of vastus medialis(coefficient=20.62),vastus lateralis(coefficient=-11.38)and rectus femoris(coefficient=-0.469)during the follow-up period 12 weeks.To sum up,ACL reconstruction can alleviate the dysfunction of patellofemoral joint to a certain extent.But,the unbalanced atrophy of quadriceps femoris once again destroyed the stability of patellofemoral joint following the operation,which might be one cause of patellofemoral joint pain and early onset of osteoarthritis after ACL reconstruction.So,rehabilitation training that focuses on quadriceps femoris especially the vastus medialis shortly following operation is suggested.