Osteoarthrosis Group Research Articles

Trajectories of quality of life and cognition in different multimorbidity patterns: Evidence from SHARE

ObjectivesThe study aimed to observe the trajectory of quality of life (QoL) and cognition, and to a analyze the bidirectional association between cognition and QoL for diverse multimorbidity patterns. MethodsIn total, 16,153 older participants age ≥50 years were included from the Survey of Health, Ageing and Retirement in Europe (SHARE). We used latent class analysis (LCA) to identify multimorbidity patterns in the baseline population. We used linear mixed models (LMM) to examine the trajectory of cognition and QoL in different multimorbidity patterns. A cross-lagged model was employed to analyze the bidirectional association between cognition and QoL in diverse multimorbidity patterns. ResultsLatent class analysis identified four multimorbidity patterns: high and low comorbidity burden (HC and LC), cardiometabolic (CA), and osteoarthrosis (OS). The HC group had the poorest cognitive function and QoL (p for trend < 0.001). Delayed and immediate episodic memory in the OS group declined at a highest rate (p for trend < 0.001). Additionally, a bidirectional association between cognition and QoL was observed. The effect of cognitive function on QoL was relatively stronger than the reverse in the CA and LC groups. ConclusionsThe rate of decline in cognition and QoL over the time differs in diverse multimorbidity patterns, and patients with four or more chronic diseases should be specially considered. Notably, early monitoring of cognitive function and can help break the vicious cycle between cognitive deterioration and poor QoL in patients with OS or CA diseases.

Imaging study on the relationship between anterior and posterior occlusal planes and temporomandibular osteoarthrosis.

The aim of this study was to compare the anterior and posterior occlusal plane characteristics of patients with different temporomandibular joint osseous statuses. A total of 306 patients with initial cone beam CT (CBCT) and cephalograms were included. They were divided into three groups on the basis of their temporomandibular joint osseous status: bilateral normal (BN) group, indeterminate for osteoarthrosis (I) group, and osteoarthrosis (OA) group. The anterior and posterior occlusal planes (AOP and POP) of the different groups were compared. Then, the regression equation was established after adjusting for confounding factors, and a correlation analysis between the occlusion planes and other parameters was performed. SNA, SNB, FMA, SN-MP, Ar-Go, and S-Go were correlated with the occlusal planes. Relative to the BN and I groups, the FH-OP of the OA group increased by 1.67° on the average, FH-POP increased by 1.42° on the average, and FH-AOP increased by 2.05° on the average. The occlusal planes were steeper in the patients with temporomandibular osteoarthrosis than in the patients without it, and the mandible rotated downward and backward. The height of the mandibular ramus, the mandibular body length, and the posterior face height were small. In clinical practice, attention should be given to the potential risk of temporomandibular joint osteoarthrosis in such patients. In addition, SNB, FMA, SN-MP, Ar-Go, S-Go, and occlusal planes had moderate correlations.

Hyoid Bone Position in Patients with and without Temporomandibular Joint Osteoarthrosis: A Cone-Beam Computed Tomography and Cephalometric Analysis.

Objective To assess the differences in hyoid bone position in patients with and without temporomandibular joint osteoarthrosis (TMJOA). Methods The present cross-sectional study was conducted in 427 participants whose osseous status was evaluated using cone-beam computed tomography and classified into normal, indeterminate osteoarthrosis (OA), and OA. The hyoid bone position and craniofacial characteristics were evaluated using cephalograms. Patients were divided into the normal group (N = 89), indeterminate OA group (N = 182), and OA group (N = 156). Descriptive statistics, one-way analysis of variance, and age- and sex-based stratified analyses were performed. P < 0.05 was considered statistically significant. Results The differences in Hy to MP, Hy-RGn, Hy to C3-RGn, C3-RGn, and Go-Hy-Me among the three groups were statistically significant. The differences in the Frankfort-mandibular plane angle, saddle angle, articular angle, gonial angle, ramus height, and posterior facial height were statistically significant. After adjusting age and sex, the Hy-RGn and C3-RGn in the normal group were significantly greater than the OA group. No statistical differences were observed in the hyoid measurements in the stratified analyses in males or subjects less than 18 years old. The differences in Hy to MP, Hy to C3-RGn, and Go-Hy-Me in female patients among the three groups were statistically significant. The differences in Hy to SN, Hy to FH, Hy to PP, Hy to MP, Hy-RGn, Hy-C3, Hy to C3-RGn, Go-Hy-Me, Hy-S, and C3-Hy-S in adults were statistically significant. Conclusion The differences in the hyoid bone position, mainly relative to the mandible, were statistically significant in patients with or without TMJOA. The difference pattern varied among different age and sex groups. Clinical evaluation of the hyoid position must consider the age and sex of patients. Longitudinal studies are required to clarify the causal relationship between TMJOA and hyoid bone position.

Cementless Total Hip Arthroplasty in Patients with Osteoarthrosis Secondary to Legg-Calvé-Perthes Disease Compared with Primary Osteoarthrosis: A Case-control Study.

Objective To perform a comparative clinical, functional and radiographic evaluation of total hip arthroplasty (THA) performed with a cementless prosthesis in cases of osteoarthrosis secondary to Legg-Calvé-Perthes Disease (LCPD) and in cases of primary osteoarthrosis. Methods In the present case-control study, we reviewed medical records of patients admitted to a university hospital between 2008 and 2015 to undergo THA due to LCPD sequelae and compared them with a control group of patients who underwent the same surgery due to primary hip osteoarthrosis. We recruited patients for clinical, functional, and radiographic analysis and we compared the evaluations in the immediate postoperative period and at the last follow-up visit, considering surgical time, size of prosthetic components, and complications. Results We compared 22 patients in the study group (25 hips) with 22 patients (25 hips) in the control group, all of whom had undergone THA with the same cementless prosthesis. There was greater functional impairment in the group of patients with LCPD sequelae ( p = 0.002). There were 4 intraoperative femoral periprosthetic fractures in the LCPD group and none in the primary osteoarthrosis group ( p = 0.050). Conclusions There is an increased risk of intraoperative periprosthetic femoral fracture and worse clinical-functional results in patients undergoing cementless THA due to osteoarthrosis secondary to LCPD sequelae than in those who have undergone the same surgery due to primary hip osteoarthrosis.

A comparative study on the radiographs of spiral CT and cone-beam CT in temporomandibular joint osteoarthrosis

Objective: To observe and compare the radiographs of spiral CT and cone-beam CT (CBCT) in the imaging of temporomandibular joint osteoarthrosis (TMJOA) and to explore the difference between CBCT and spiral CT in detection accuracy so as to provide references for clinical diagnosis and treatment. Methods: A total of 52 patients with TMJOA diagnosed in the Department of Oral and Maxillofacial Surgery, General Hospital of Chinese PLA, from January 2018 to December 2019 were selected. There were 10 males and 42 females, with an average age of 38.6 years (21-70 years). All patients underwent spiral CT and CBCT examinations. Two oral radiologists and two oral and maxillofacial surgeons measured and evaluated the joint spaces and condylar bone lesions of each side of temporomandibular joint. According to the presence or absence of osteoarthrosis, the patients were divided into osteoarthrosis group (92 sides) and non osteoarthrosis group (12 sides). The mean size of joint spaces and the detection rate of lesions were compared between the two groups. SPSS 20.0 was used to analyze the data. Results: There was no significant difference between the measurements of joint space size and joint position in the spiral CT group and the CBCT group (P>0.05). The mean size of the anterior space and the ratio of the posterior condyle in the osteoarthrosis side were larger than that in the normal side. The LR index was smaller in the osteoarthrosis side than that in the normal side indicating that the position of the posterior condyle in the osteoarthrosis side was deviated. However, the difference was not statistically significant (P>0.05). Both spiral CT and CBCT showed good consistency in displaying condylar osteopathy. The most common types of condylar osteopathy was surface defect. The detection rates of defects by spiral CT were surface erosion (85.6%, 89/104), articular surface flattening and shortening (82.7%, 86/104), subcortical sclerosis (40.4%, 42/104), osteophyte (40.4%, 42/104) and subcortical cyst (11.5%, 12/104) respectively. The detection rates of defects by CBCT were surface erosion (88.5%, 92/104), articular surface flattening and shortening (86.5%, 90/104), subcortical sclerosis (35.6%, 37/104), osteophyte (41.3%, 43/104) and subcortical cyst (11.5%, 12/104). There was no statistical difference between the two groups (P>0.05), respectively. Conclusions: Both spiral CT and CBCT showed good accuracies in displaying the osteopathy of TMJOA and the sizes of the joint spaces measured by spiral CT and CBCT were basically the same. Both spiral CT and CBCT could be used as a routine diagnostic method for TMJOA.

QUANTIFICATION OF NEURAL ELEMENTS IN POSTERIOR CRUCIATE LIGAMENT: COMPARISON BETWEEN HEALTHY KNEES AND WITH PRIMARY OSTEOARTHROSIS

ABSTRACTObjective: To quantify the neural elements in the posterior cruciate ligament (PCL) in healthy knees and with primary osteoarthrosis (OA).Methods: In two groups with OA, one of cadavers and another of individuals, the area of neural elements identified in histological sections of PCL with anti-S100 immunohistochemistry was quantified.Results: The overall mean area of the neural elements was 0.96% ± 0.67%, with the value in the cadaver group of 1.02% ± 0.67% and in the OA group of 0.80% ± 0.64%, with a significant statistically difference (p = 0.001). No correlation was observed between neural element quantification and the age of the individuals (p > 0.05). There was no difference in the quantification of neural elements between the sexes in the cadaver group (p = 0.766), but in the OA group there was a statistically significant reduction in males (p = 0.003). Also, in the osteoarthrosis group there was no difference in the quantification of neural elements in the knees with varus or valgus alignment (p = 0.847).Conclusion: There was a decrease in neural element quantification in PCL of individuals affected by OA in relation to non-arthritic individuals, with this quantification not related to age or with the axis of the lower limb. However, this quantification is not related to age or the axis of the lower limb.Level of Evidence III, Case control study.

Prevalence of temporomandibular disorders in postmenopausal women and relationship with pain and HRT.

The prevalence of temporomandibular disorders (TMD) is higher in females, reaching their high peak during reproductive years, probably because of the action of some female hormones, which alter pain threshold. This study aimed to investigate the prevalence of TMD in postmenopausal women and its relationship with pain and hormone replacement therapy (HRT). In total, 284 patients were evaluated and classified using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Pain was measured using the Visual Analogue Scale (VAS), and patients were also asked about the use of HRT. All data was analyzed using analysis of variance (ANOVA) and chi-square test. In total, 155 subjects did not have TMD and 129 had TMD; TMD group patients were classified according to RDC/TMD axis I classification as follows: muscle disorder group (1.6%), disk displacement group (72.87%), and arthralgia, osteoarthritis, and osteoarthrosis group (37.98%). Pain was registered in 35 patients who belonged to the TMD group, while 48 patients reported the use of HRT. There was a similar percentage of TMD and non TMD patients; moreover, the use of exogenous hormones was no associated with TMD, suggesting that there is no influence on the pain threshold.

Tougu Xiaotong capsule inhibits the tidemark replication and cartilage degradation of papain-induced osteoarthritis by the regulation of chondrocyte autophagy

The tidemark is located between calcified and non-calcified cartilage matrices. Tidemark replication plays an important role in the pathogenesis of osteoarthrosis (OA). Autophagy, or cellular self-digestion, is an essential cellular homeostasis mechanism that was found to be deficient in osteoarthritic cartilage. This study evaluated the effects of Tougu Xiaotong capsule (TXC) on the tidemark replication and cartilage degradation, and also investigated LC3 I/II, which executes autophagy, the potential role of ULK1, an inducer of autophagy, and Beclin1, a regulator of autophagy, in the development of a papain-induced OA in rat knee joints. Using a papain-injected knee rat model, standard histological methods were used to validate our model as well as treatment with TXC or glucosamine (GlcN). After 12 weeks of treatment, the changes of cartilage structure were observed by digital radiography (DR), optical microscopy, scanning electron microscopy and transmission electron microscopy, and the LC3 I/II, ULK1 and Beclin1 levels were measured by western blotting. Cartilage degradation was evaluated by the Mankin score on paraffin-embedded sections stained with SafraninO-fast green. TXC was found to improve the arrangement of subchondral bone collagen fibers and calcium phosphate crystals, inhibit the tidemark replication and delay the cartilage degradation in the papain-induced OA. Our results also showed that LC3 I/II, ULK1 and Beclin1 levels in both the TXC+OA and GlcN+OA groups were significantly increased compared to those in the OA group. The results indicate that TXC could inhibit the tidemark replication and cartilage degradation by the regulation of chondrocyte autophagy.

Association Between Altered Somatosensation, Pain, and Knee Stability in Patients With Severe Knee Osteoarthrosis

To examine the relationship between knee pain, altered somatosensation, and self-reported instability in individuals with knee osteoarthrosis (OA) during a step-up-and-over task. Quantitative sensory testing, including mechanical detection threshold (MDT), allodynia, vibration perception threshold, and pressure pain threshold (PPT), was assessed in 16 individuals (mean age, 52 ± 7 y) with knee OA and in 16 age-matched and sex-matched controls. Pain intensity ratings and subjective reports of instability/buckling were recorded at rest and while performing a step-up task, and these findings were correlated with somatosensory measures. In the OA group, all participants reported allodynia on MDT testing. Compared with healthy controls, MDT was significantly increased (P<0.001), and vibration perception threshold was increased (P=0.02) at the medial knee, indicating hypoesthesia. PPT was significantly decreased at the medial joint line (P=0.03) and 12 cm distal (P=0.02). Comparing participants with OA having severe versus mild radiographic changes, PPT was lower at the medial joint line (P<0.01) but not at 12 cm distal. Fourteen (87.5%) participants with knee OA reported pain and instability during the step task as compared with none or 1 (6%) of the controls. On the step task, longer duration of symptoms was associated with increased pain (P=0.02). A moderate correlation between greater self-reported instability and increased vibratory hypoesthesia at the knee (r=-0.633; P=0.01) was demonstrated, suggesting a potential relationship between somatosensory changes and functional deficits. Severe OA may result in both hyperalgesia and hypoesthesia at the affected knee. Perceived instability during functional tasks may be mediated in part by pain in individuals with knee OA.

Predictive value of femoral head heterogeneity for fracture risk

Osteoporosis (OP) is characterized by low bone mass and weak bone structure, which results in increased fracture risk. It has been suggested that osteoporotic bone is strongly adapted to the main loading direction and less adapted to the other directions. In this study, we hypothesized that osteoporotic femoral heads have 1) an increased anisotropy; 2) a more heterogenic distribution of bone volume fraction (BV/TV) throughout the femoral head; and, 3) a more heterogenic distribution of the trabecular thickness (Tb.Th.) throughout the femoral head, as compared to non-osteoporotic bone. To test these hypotheses, we used 7 osteoporotic femoral heads from patients who fractured their femoral neck and 7 non-fractured femoral heads from patients with osteoarthrosis (OA). Bone structural parameters from the entire trabecular region were analyzed using microCT. We found that the degree of anisotropy was higher in the fractured femoral heads, i.e. 1.72, compared to a value of 1.61 in the non-fractured femoral heads. The BV/TV and Tb.Th. and their variations throughout the femoral head, however, were all significantly lower in the fractured group. Hence, the first hypothesis was confirmed, whereas the other two were rejected. Interestingly, the variation of Tb.Th. throughout the femoral head provided a 100% discrimination between the OP and OA groups, i.e. for the same BV/TV, all fractured cases had a less heterogenic distribution. In conclusion, our results suggest that bone loss in OP takes place uniformly throughout the femoral head, leading to an overall decrease in bone mass and trabecular thickness. Furthermore, the variation of Tb.Th. in the femoral head could be an interesting parameter to improve the prediction of fracture risk in the proximal femur.

Bone marrow edema in the knee in osteoarthrosis and association with total knee arthroplasty within a three-year follow-up

ObjectiveThe purpose of this study was to determine if a correlation exists between magnetic resonance imaging (MRI) findings of bone marrow edema (BME) in osteoarthrosis (OA) of the knee joint and need for total knee arthroplasty (TKA) within a follow-up period of 3 years.Materials and methodsThe entire database of knee MR studies over a 3-year period was used to select individuals with knee OA. A chart review was conducted to identify and include only those who had a 3-year follow-up appointment from the time of the initial MR study. There were 25 patients in the OA-only group (four men and 21 women; age range, 28–75; average age, 49.3 years). The OA and BME group had 48 patients (23 men and 25 women; average age, 55.5 years). The MRs were reviewed and interpreted by a musculoskeletal radiologist and were classified into one of four patterns of BME: none, focal, global, or cystic pattern. Meniscal tear and degree of cartilage loss were also assessed.ResultsSubjects who had BME of any pattern type were 8.95 times as likely to progress rapidly to a TKA when compared to subjects with no BME (p = 0.016). Subjects with a global pattern of BME were 5.45 times as likely to have a TKA compared to subjects with focal, cyst, or no BME (p < 0.05). Subjects with a global edema pattern were 13.04 times as likely to have a TKA than subjects with no marrow edema in the knee (p < 0.01). There was no correlation of TKA with meniscal tear or cartilage loss. The group of subjects who had a TKA were 12.6 years older than those who did not have a TKA (p < 0.001). However, the BME results were still significant after accounting for the age difference.ConclusionOur classification of patterns into global, focal, cystic, and absence of BME is an attempt to further define edema in osteoarthrosis and how it relates to clinical progression. Patients with BME and OA have an increased risk of TKA as opposed to OA and no marrow edema. The BME pattern with the worst prognosis for the knee is the global pattern.

Expression of urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor in synovial fluid of patients with temporomandibular disorders

To investigate the level of urokinase-type plasminogen activator (uPA) and urokinase-type plasminogen activator receptor (uPAR) in synovial fluid of patients with temporomandibular disorders and to analyze their relation with temporomandibular disorders (TMD). Synovial fluid was obtained from 64 sides of 56 TMD patients and from 16 sides of 10 asymptomatic healthy volunteers (control). The concentrations of uPA and uPAR in the synovial fluid were measured by ELISA. Forty-eight sides of TMD were divided into 3 groups: arthrosis, structure disorder and osteoarthrosis, each including 16 sides. The levels of uPA and uPAR were significantly higher in the synovial fluid of TMD patients than that in the control group (P < 0.05), and the level of uPA and uPAR in osteoarthrosis group was significantly higher than that in arthrosis and structure disorder group (P < 0.05). However, there was no difference in expression of uPA and uPAR between arthrosis and structure disorder groups (P > 0.05). uPA and uPAR in the synovial fluid may play a role in the pathogenesis of TMD, and the level of uPA and uPAR in synovial fluid of TMD could be used as a biochemical markers to reflect pathological degree of TMD.

Increased Responsiveness to Toll‐Like Receptor 4 Stimulation in Peripheral Blood Mononuclear Cells from Patients with Recent Onset Rheumatoid Arthritis

Background. Cell signaling via Toll-like receptors (TLRs) leads to synovial inflammation in rheumatoid arthritis (RA). We aimed to assess effects of TLR2 and TLR4 stimulation on proinflammatory cytokine production by peripheral blood mononuclear cells (PBMCs) from patients with recent-onset RA, osteoarthrosis (OA), and healthy control (HC). Methods. PBMCs were stimulated with LPS, biglycan and cytokine mix. Cytokines were analyzed in supernatants with ELISA. Expression of toll-like receptors mRNA in leukocytes was analyzed using real-time qPCR. Results. PBMCs from RA patients spontaneously produced less IL-6 and TNFα than cells from OA and HC subjects. LPS increased cytokines' production in all groups. In RA patients increase was dramatic (30 to 48-fold and 17 to 31-fold, for respective cytokines) compared to moderate (2 to 8-fold) in other groups. LPS induced 15-HETE generation in PBMCs from RA (mean 251%) and OA patients (mean 43%), although only in OA group, the increase was significant. TLR2 and TLR4 gene expressions decreased in response to cytokine mix, while LPS enhanced TLR2 expression in HC and depressed TLR4 expression in OA patients. Conclusion. PBMCs from recent-onset RA patients are overresponsive to stimulation with bacterial lipopolysaccharide. TLR expression is differentially regulated in healthy and arthritic subjects.

Modular Uncemented Tricompartmental Total Knee Arthroplasty

The incidence of posttraumatic osteoarthrosis, especially in younger patients, increases. In different studies total knee arthroplasty (TKA) is only indicated in 0–12% of cases of posttraumatic osteoarthrosis, because most authors feel that the indication for TKA in younger patients should be narrowly restricted. The most common indications for TKA include primary idiopathic osteoarthrosis and rheumatoid arthritis predominantly in patients > 60 years. In this prospective study a total of 188 patients with 197 TKAs were compared. 92 patients (93 TKAs) had a posttraumatic osteoarthrosis, 96 patients (104 TKAs) a nontraumatic osteoarthrosis. All patients received the same modular tricompartmental TKA in uncemented technique regarding femoral and tibial component. The patella was always cemented. All operations were performed by a group of six surgeons in a standardized operating technique. The evaluation of the study parameters included three components: patient questionnaire (pain, patient satisfaction, ability to walk, range of motion, workplace situation), clinical evaluation (Knee Society Clinical Rating Score), conventional X-ray, and CT evaluation (axial alignment, radiolucent lines, bone defects). In light of the results obtained in this study, TKA implantation appears to be a valid primary treatment option in young patients with posttraumatic arthrosis. Even though the results for nearly all parameters were poorer in the posttraumatic osteoarthrosis group, the condition of these patients still improved significantly following TKA.

Low IGF-I in synovial fluid and serum in patients with aseptic prosthesis loosening

Background We have previously shown that proliferation in primary cultures of human osteoblast-like cells is lower after exposure to synovial fluid from patients with aseptic prosthesis loosening than after exposure to synovial fluid from patients with osteoarthrosis.Materials and methods Insulin-like growth factors (IGF) I and II and IGF binding proteins (IGFBP) 3–6, were measured with radioimmunoassy in synovial fluid and in serum from patients with aseptic prosthesis loosening or osteoarthrosis. Proliferation in osteoblast-like MG-63 cells was studied with the CyQUANT assay.Results IGF-I and IGFBP-4 concentrations were lower whereas the concentration of IGFBP-6 was higher in synovial fluids from patients with prosthesis loosening than in synovial fluid from patients with osteoarthrosis. IGF-I concentrations in serum from patients with prosthesis loosening were also lower than in the osteoarthrosis group, and were even below the normal range in most cases (72%). Synovial fluid from patients with aseptic loosening had a weaker stimulatory effect on MG63 osteoblast-like cell proliferation than synovial fluid from patients with osteoarthrosis, but there was no difference between the two groups when a human IGF-I antibody was added.Interpretation Low levels of IGF-I in synovial fluid possibly result from low serum levelsand may be a mechanism leading to aseptic prosthesis loosening.

Increased risk of dislocation after primary total hip arthroplasty in inflammatory arthritisA prospective observational study of 410 hips

It is unclear whether patients with inflammatory arthritis have a higher risk of dislocation after hip replacement. We carried out a prospective study assessing the incidence of dislocation within 2 years after surgery for patients diagnosed with inflammatory arthritis (IA) and osteoarthrosis (OA). One single type of prosthesis was implanted using a lateral approach. Both diagnostic groups were compared by univariate analysis with respect to dislocation, sex, age, diagnosis, prior hip surgery, experience of the surgeon and malposition of the acetabular component. In a multivariate logistic regression approach, the difference in dislocation incidence was assessed after adjusting for the effect of the potential confounders given above. Between 1996 and 1999, 410 THA were performed: 70 in IA and 340 in OA. After 2 years no patients were lost to follow-up, but 12 patients had died, and 5 revisions were carried out for reasons other than dislocation. The dislocation rate in patients with IA was higher than in patients with OA: 10% (7 hips) in the IA group and 3% (10 hips) in the OA group (p = 0.006). No significant differences were found among the risk factors for dislocation between the two groups. Multivariate logistic regression analysis showed that IA is an independent risk factor for dislocation (odds ratio (OR) 3.7, 95% CI 1.3-11), together with malposition of the cup in more than 55 degrees abduction (OR 7.7, CI 2.3-26) and increased anteversion (OR 7.6, CI 1.4-42.4). Our findings clearly suggest that inflammatory arthritis has to be considered as an independent risk factor for dislocation after primary THA.

Identification of sequence polymorphisms of the COMP (cartilage oligomeric matrix protein) gene and association study in osteoarthrosis of the knee and hip joints.

Osteoarthrosis (OA) is a common cause of musculoskeletal disability characterized by late-onset degeneration of articular cartilage. Although several candidate genes have been reported, susceptibility genes for OA remain to be determined. Hereditary osteochondral dysplasias produce severe, early-onset OA and hence are models for common idiopathic OA. Among them are pseudoachondroplasia and multiple epiphyseal dysplasia, both of which are caused by mutations in the cartilage oligomeric matrix protein (COMP) gene. Therefore, COMP may be a susceptibility gene for OA. We screened for polymorphisms by direct sequencing of all exons of the COMP gene with their flanking intron sequences and the promoter region. We identified 16 polymorphisms, of which 12 were novel. Using six polymorphisms spanning the entire COMP gene, we examined the association of COMP in Japanese patients with OA of the knee and hip joints. Genotype and allele frequencies of the polymorphisms were not significantly different between OA and control groups, and there was no significant difference in haplotypes. These results do not support an association between COMP and OA in the Japanese population.

Quantitative evaluation of gait pattern in patients with osteoarthrosis of the knee before and after total knee arthroplasty. Gait analysis using a pressure measuring system

Using a pressure measuring system, we quantitatively evaluated gait pattern in patients with osteoarthrosis (OA) of the knee before and after total knee arthroplasty (TKA). In the OA group, the stance time was longer, and the average vertical component of the floor reaction force (AVF) was lower than the values in normal age-matched subjects. These gait parameters correlated with the clinical score. These results suggest that changes in the gait parameters reflect gait patterns that reduce load on the knee. The center of pressure (COP) under the foot was correlated with the axial alignment of the lower limb in the mid-stance phase. In the TKA group, the clinical scores and gait parameters were improved 12 months after surgery compared with the preoperative values. The COP in the mid-stance phase moved inward after the TKA. However, in patients examined more than 2 years after a TKA, stance time and AVF did not reach normal levels, despite the patients’ good clinical scores. These findings indicate that the gait pattern before surgery continues although pain on walking is reduced early after a TKA. Gait evaluation with a simple pressure measuring system revealed the changes in gait that are difficult to define by subjective clinical assessment.

Survivorship analysis of cemented total condylar knee arthroplasty: A long-term follow-up report on 348 cases

Survivorship analysis was used in the evaluation of 348 consecutive primary total condylar knee arthroplasties (total knee arthroplasties) performed on 253 patients in a 27-month period, with a maximum follow-up period of 12 years. The diagnosis was osteoarthrosis in 184 cases and rheumatoid arthritis in 164 cases. Ten patients (10 total knee arthroplasties) were lost to follow-up evaluation. The endpoint was defined as prosthesis not in situ. The variables considered were age, sex, body mass index, and diagnosis. The overall cumulative survival rate was 92%. The survival rate of the osteoarthrosis group was significantly higher (97%) than that of the rheumatoid arthritis group (87%). None of the other variables affected survival rate significantly.

Characteristics and treatment outcome of diagnostic subgroups of CMD patients: retrospective study.

The records of 193 randomly chosen patients with CMD referred 2.5 yr previously were examined retrospectively for anamnestic, clinical and radiological findings and observations related to treatment. These data were supplemented with information from questionnaires sent to all treated patients in which their opinion on the treatment outcome was asked. Within the patient group, four diagnostic subgroups were distinguished. Three subgroups consisted of patients with the diagnoses CMD with a mainly myogenous component, osteoarthrosis and internal derangement respectively, whereas the fourth subgroup consisted of patients who did not fit into one of these categories. Differences between the four groups were found concerning mean age, the prevalence of a limited range of motion, headache, psychosocial factors, loss of posterior tooth support and objective treatment outcome. The patients with CMD with a mainly myogenous component showed the highest percentages of CMD associated disorders, the least successful treatment outcome and the highest percentage of renewed treatment. The patients with internal derangement showed the lowest mean age, the highest prevalence of a limited range of motion and the best treatment outcome. The patients in the osteoarthrosis group showed the highest mean age and the highest percentage of loss of posterior tooth support. It may be concluded that the evaluation of diagnostic subgroups of CMD patients has to be preferred in the assessment of a heterogeneous group of patients with CMD.