Marked differences in local bone remodelling in response to different marrow stimulation techniques in a large animal.

Marrow stimulation, including subchondral drilling and microfracture, is the most commonly performed cartilage repair strategy, whereby the subchondral bone plate is perforated to release marrow-derived cells into a cartilage defect to initiate repair. Novel scaffolds and therapeutics are being designed to enhance and extend the positive short-term outcomes of this marrow stimulation. However, the translation of these newer treatments is hindered by bony abnormalities, including bone resorption, intralesional osteophytes, and bone cysts, that can arise after marrow stimulation. In this study, three different marrow stimulation approaches - microfracture, subchondral drilling and needle-puncture - were evaluated in a translationally relevant large-animal model, the Yucatan minipig. The objective of the study was to determine which method of marrow access (malleted awl, drilled Kirschner wire or spring-loaded needle) best preserved the underlying subchondral bone. Fluorochrome labels were injected at the time of surgery and 2 weeks post-surgery to capture bone remodelling over the first 4 weeks. Comprehensive outcome measures included cartilage indentation testing, histological grading, microcomputed tomography and fluorochrome imaging. Findings indicated that needle-puncture devices best preserved the underlying subchondral bone relative to other marrow access approaches. This may relate to the degree of bony compaction occurring with marrow access, as the Kirschner wire approach, which consolidated bone the most, induced the most significant bone damage with marrow stimulation. This study provided basic scientific evidence in support of updated marrow stimulation techniques for preclinical and clinical practice.

Outcome of Osteophytes After Only-Fixation as Treatment for Multilevel Cervical Spondylosis-A Minimum of 12 Months Follow-Up.

OBJECTIVE: This report analyzes the significance of osteophytes in the overall pathologic scheme in patients with single-level or multilevel cervical spinal degeneration. METHODS: From January 2010 to December 2018, 249 patients with cervical spondylosis were surgically treated. The alterations in ventral compression caused by disc bulges, osteophytes, and ligament buckling (disc-osteophye-ligament [DOL] complex) at single or multiple levels were evaluated after surgical treatment that involved only spinal fixation and did not involve any kind of bone or soft tissue decompression. Delayed (≥1 year after surgery) postoperative imaging was available in 165 patients and these patients formed the study group. Forty-five patients underwent facet distraction arthrodesis (group A), 106 patients underwent only-fixation involving transarticular screw insertion (group B), and 14 patients underwent hybrid fixation that involved both intra-articular spacers and transarticular fixation techniques (group C) as the surgical treatment. RESULTS: The size of the DOL complex at the segments that underwent fixation was reduced in 136 patients. The size of the DOL complex or its related dural or neural compression did not increase in any of the cases evaluated. Reduction in the size of DOL was more pronounced in patients in group A in both immediate postoperative and delayed images and in patients in group C at spinal levels at which facet distraction was performed using facet distraction spacers. CONCLUSIONS: Spinal stabilization reduces the size of osteophytes. Facet distraction spacers are more effective in reduction of the size of DOL in both immediate and delayed postoperative periods.

Hand strenght and dexterity in interphalangeal hand osteoarthritis and effects of osteophyte formations.

BACKGROUND: Hand osteoarthritis (HOA) is a complex disorder with various subtypes characterized with predominance of different features. It is challenging to estimate the severity of hand disability in HOA, since contribution of different disease components to clinical burden is yet to be clarified. The aim of the study is to investigate hand functions in nonerosive interphalangeal hand osteoarthritis (HOA) without inflammatory features, and search for effects of osteophyte formations detected by radiography and ultrasound on functionality. METHODS: Thirty one HOA patients and 20 healthy subjects with similar age, gender, body mass index were included. Hand functions were evaluated by self-reported questionnaires and objective strength and dexterity measurements. A total of 459 interphalangeal joints were evaluated and scored by radiography and ultrasound for ostephyte formations. RESULTS: Strength and dexterity measurements were similar between groups. Self-reported functionality was hampered in HOA group but not statistically significant. Osteophyte scores obtained by ultrasound and radiography were significantly higher in HOA group. Osteophyte scores obtained by ultrasound were higher than the scores obtained by radiography. Ultrasound scores showed no correlation with any of the parameters while osteophytes scores obtained by radiography partially showed a significant negative correlation with assembly part of dexterity testing. CONCLUSIONS: No significant difference observed in hand strength and dexterity in nonerosive interphalangeal HOA patients withouth signs of inflammation when compared to healthy subjects. Osteophyte formations prominent enough to be deteceted by radiography may have a negative effect on hand dexterity.

Individuals with high bone mass have increased progression of radiographic and clinical features of knee osteoarthritis.

OBJECTIVE: High bone mass (HBM) is associated with an increased prevalence of radiographic knee OA (kOA), characterized by osteophytosis. We aimed to determine if progression of radiographic kOA, and its sub-phenotypes, is increased in HBM and whether observed changes are clinically relevant. DESIGN: A cohort with and without HBM (L1 and/or total hip bone mineral density Z-score≥+3.2) had knee radiographs collected at baseline and 8-year follow-up. Sub-phenotypes were graded using the OARSI atlas. Medial/lateral tibial/femoral osteophyte and medial/lateral joint space narrowing (JSN) grades were summed and Δosteophytes, ΔJSN derived. Pain, function and stiffness were quantified using the WOMAC questionnaire. Associations between HBM status and sub-phenotype progression were determined using multivariable linear/poisson regression, adjusting for age, sex, height, baseline sub-phenotype grade, menopause, education and total body fat mass (TBFM). Generalized estimating equations accounted for individual-level clustering. RESULTS: 169 individuals had repeated radiographs, providing 330 knee images; 63% had HBM, 73% were female, mean (SD) age was 58 (12) years. Whilst HBM was not clearly associated with overall Kellgren-Lawrence measured progression (RR = 1.55 [0.56.4.32]), HBM was positively associated with both Δosteophytes and ΔJSN individually (adjusted mean differences between individuals with and without HBM 0.45 [0.01.0.89] and 0.15 [0.01.0.29], respectively). HBM individuals had higher WOMAC knee pain scores (ß = 7.42 [1.17.13.66]), largely explained by adjustment for osteophyte score (58% attenuated) rather than JSN (30% attenuated) or TBFM (16% attenuated). The same pattern was observed for symptomatic stiffness and functional limitation. CONCLUSIONS: HBM is associated with osteophyte progression, which appears to contribute to increased reported pain, stiffness and functional loss.

Osteoarthritis, Osteophytes, and Enthesophytes Affect Biomechanical Function in Adults With X-linked Hypophosphatemia.

CONTEXT: X-Linked hypophosphatemia (XLH) is a lifelong metabolic disease with musculoskeletal comorbidities that dominate the adult clinical presentation. OBJECTIVE: The adult XLH disorder has yet to be quantified on the basis of the physical and functional limitations that can affect activities of daily living. Our goal was to report the impact of the musculoskeletal manifestations on physical function. DESIGN AND SETTING: Musculoskeletal function was evaluated by validated questionnaires and in an interdisciplinary clinical space where participants underwent full-body radiologic imaging, goniometric range of motion (ROM) measurements, general performance tests, and kinematic gait analysis. PATIENTS: Nine adults younger than 60 years with a diagnosis of XLH and self-reported musculoskeletal disability, but able to independently ambulate, were selected to participate. Passive ROM and gait analysis were also performed on age-approximated controls to account for differences between individual laboratory instrumentation. RESULTS: Enthesophytes, degenerative arthritis, and osteophytes were found to be consistently bilateral and diffusely present at the spine and synovial joints across participants, with predominance at weight-bearing joints. Passive ROM in adults with XLH was decreased at the cervical spine, hip, knee, and ankle compared to controls. Gait analysis relative to controls revealed increased step width, markedly increased lateral trunk sway, and physical restriction at the hip, knees, and ankle joints that translated into limitations through the gait cycle. CONCLUSIONS: The functional impact of XLH musculoskeletal comorbidities supports the necessity for creating an interprofessional health-care team with the goal of establishing a longitudinal plan of care that considers the manifestations of XLH across the lifespan.

Multiscale bone quality analysis in osteoarthritic knee joints reveal a role of the mechanosensory osteocyte network in osteophytes.

Osteophytes - bony outgrowths on joint structures - are found in healthy individuals but are specifically present in late osteoarthritis (OA). Osteophyte development and function is not well understood, yet biomechanical stimuli are thought to be critical. Bone adapts to mechanical forces via the cellular network of osteocytes. The involvement of osteocytes in osteophyte formation and maturation has not been unravelled. Forty-three osteophytes from tibias of 23 OA patients (65 ± 9 years) were analysed. The trabecular bone structure of osteophytes presented with fewer trabeculae of lower bone mineral density compared to subchondral bone. We identified 40% early stage and 60% late stage osteophytes that significantly differed in their trabecular bone characteristics. Osteophyte bone revealed a higher number of osteocytes and a lower number of empty osteocyte lacunae per bone area than the subchondral bone. We found that OA osteophytes consist of younger bone material comprised of woven and lamellar bone with the capacity to develop into a late stage osteophyte potentially via the involvement of the osteocyte network. Our analysis of OA osteophytes implies a transition from woven to lamellar bone as in physiological bone growth within a pathological joint. Therefore, osteophyte development and growth present a valuable research subject when aiming to investigate the osteogenic signalling cascade.

Musculoskeletal ultrasound in symptomatic thumb-base osteoarthritis: clinical, functional, radiological and muscle strength associations.

BACKGROUND: Thumb-base osteoarthritis (OA) is a common cause of pain and disability This study aimed to investigate the associations of musculoskeletal ultrasound OA pathologies with the extent of pain, function, radiographic scores, and muscle strength in symptomatic thumb-base osteoarthritis. METHODS: This is a cross-sectional study of an ongoing clinical trial with eligibility criteria including thumb-base pain on Visual Analogue Scale (VAS) ≥40 (0 to 100 mm), Functional Index for Hand OA (FIHOA) ≥ 6 (0 to 30) and Kellgren Lawrence (KL) grade ≥ 2. The most symptomatic side was scanned to measure synovitis and osteophyte severity using a 0-3 semi-quantitative score, power Doppler and erosion in binary score. A linear regression model was used for associations of ultrasound findings with VAS pain, FIHOA and hand grip and pinch strength tests after adjusting for age, gender, body mass index, disease duration and KL grade as appropriate. For correlation of ultrasound features with KL grade, OARSI ((Osteoarthritis Research Society International) osteophyte and JSN scores, Eaton grades, Spearman coefficients were calculated, and a significant test defined as a p-value less than 0.05. RESULTS: The study included 93 participants (mean age of 67.04 years, 78.5% females). Presence of power Doppler has a significant association with VAS pain [adjusted ß coefficient = 11.29, P = 0.02] while other ultrasound pathologies revealed no significant associations with all clinical outcomes. In comparison to radiograph, ultrasonographic osteophyte score was significantly associated with KL grade [rs = 0.44 (P < 0.001)], OARSI osteophyte grade [rs = 0.35 (P = 0.001)], OARSI JSN grade [rs = 0.43 (P < 0.001)] and Eaton grade [rs = 0.30 (P < 0.01)]. Ultrasonographic erosion was significantly related with radiographic erosion [rs = - 0.49 (P = 0.001)]. CONCLUSION: From a clinical perspective the significant relationship of power Doppler with pain severity in thumb base OA suggests this might be a useful tool in understanding pain aetiology. It is important to recognise that power Doppler activity was only detected in 14% of the study so this might be an important subgroup of persons to monitor more closely. TRIAL REGISTRATION: Registered at Australian New Zealand Clinical Trials Registry (ANZCTR), http://www.anzctr.org.au/ , ACTRN12616000353493.

Spondylosis deformans as an indicator of transport activities in archaeological dogs: A systematic evaluation of current methods for assessing archaeological specimens.

Over the past several decades archaeologists have used the spinal pathology spondylosis deformans as an indicator that archaeological dogs were used to pull or carry loads. This interpretive approach is largely based upon observations of prehistoric dog remains and archaeologist's interpretations of veterinary literature on recent sled dogs and other draft animals. However, no comparative large-scale studies of the occurrence of spondylosis deformans in wild canids, transport dogs, and dogs never involved in pulling or carrying loads have been published. To evaluate the reliability of spondylosis deformans in archaeological dogs as an indicator of participation in transport activities, 136 modern non-transport dogs, 19 sled dogs, and 241 wolves were systematically analyzed for the occurrence of spondylosis deformans. Our results indicate this pathology is not a reliable skeletal indicator of dog transport because the disease is prevalent in both dogs and wolves, regardless of their occupational histories. Numerous factors correlate with the occurrence and manifestation of this disease in canids, including age, body size, sex, and inbreeding. As such, it remains extremely challenging to identify specific etiologies for spondylosis deformans in archaeological specimens.

Spinal sagittal alignment and trapezoidal deformity in patients with degenerative cervical spondylolisthesis.

Degenerative cervical spondylolisthesis (DCS) is a cervical deformity arising from regressive changes where trapezoidal deformity characterized by hypertrophic osteophytes of spinal elements is often observed. There is a paucity of literature about the spinal contour of DCS and trapezoidal vertebrae. We conducted this research to clarify the relationship between spinal sagittal alignment and trapezoidal deformity in DCS. Total seventy-nine patients with cervical spondylosis were enrolled. Twenty-four patients who exhibited cervical spondylolisthesis were classified into DCS group. Other patients were classified into a control group. Measurements of radiographic parameters and trapezoidal deformity were made. DCS was found mostly in C3-C4 and C4-C5 (16 and 10 cases, respectively). T1S and T1-T4 TK was larger in the DCS group than in the control (T1S: 29.9 ± 2.3° vs. 23.7 ± 1.5°, T1-T4 TK: 14.9 ± 2.1° vs. 9.0 ± 1.4°). C2-C7A was smaller in DCS (3.5 ± 3.6° vs. 11.9 ± 2.3°). Trapezoidal deformity was apparent in the vertebra below the slipped segment. Among sagittal parameters, T1S and T1-T4 TK were positively correlated with DCS (r = 0.523 and r = 0.438, respectively). For these correlations with DCS, both logistic and linear regression models predicted threshold values of approximately 30° for T1S and 15° for T1-T4 TK responsible for DCS. DCS was mostly found in the middle cervical region. Among sagittal parameters, enlarged T1S and T1-T4 TK, which were strongly correlated with amount of slippage, was considered affected to DCS. Cervical kyphosis and trapezoidal deformity also exhibited strong correlations with DCS, and were considered responsible for clinical instability.

Ambulatory activity interacts with common risk factors for osteoarthritis to modify increases in MRI-detected osteophytes.

OBJECTIVE: To investigate the longitudinal association between objectively measured ambulatory activity (AA) and knee MRI-detected osteophytes (OPs), and to test whether this relationship was modified by common risk factors for OA including sex, obesity, disease severity and knee injury history. METHODS: 408 community-dwelling adults aged 51-81 years were assessed at baseline and 2.7 years. T1-weighted fat-suppressed MRI was used to evaluate knee OPs at both time points. AA was assessed at baseline by pedometers and categorized as: less active (≤7499 steps per day), moderately active (7500-9999 steps per day) and highly active (≥10,000 steps per day). RESULTS: Statistically significant interactions were detected between knee OA risk factors and AA on increases in MRI-detected OPs (all P < 0.05). In stratified analyses, being moderately active, compared to being less active, was protective against an increase in MRI-detected OPs (score change of ≥1) in females (relative risk (RR) = 0.42, 95%CI, 0.25-0.70, P < 0.01), those who were obese (RR = 0.50, 95%CI, 0.30-0.83, P < 0.01), those with radiographic OA (ROA) (RR = 0.68, 95%CI, 0.47-0.97, P = 0.02) and those with a history of knee injury (RR = 0.27, 95%CI, 0.08-0.88, P = 0.02) in almost every knee compartment, after adjustment for confounders. No statistically significant associations were found in males, non-obese, non-ROA or non-injury groups. CONCLUSIONS: Being moderately active is protective against an increase in MRI-detected OPs in females, those with ROA, those who are obese and those with a history of knee injury. These findings suggest that being moderately active is beneficial for individuals who are at higher risk of knee OA.

Osteophytes in the Cervical Vertebral Bodies (C3-C7)-Demographical Perspectives.

Vertebral osteophytes are an age-dependent manifestation of degenerative changes in the spine. We aimed to determine the prevalence and severity of cervical osteophytosis in a large study population. To do so, we developed a grading system for osteophytosis, enabling the assessment of their presence and severity in the cervical spine, and applied it to the analysis of dried cervical vertebral bodies (C3-C7) from 273 individuals. Statistical analyses were carried out per motion segment, while testing for the effect of age, sex, and ethnicity. The highest prevalence of osteophytes was found in motion segment C5/C6 (48.2%), followed by C4/C5 (44.1%), and last C6/C7 and C3/C4 (40.5%). Severe osteophytes are most commonly seen in motion segment C5/C6. In all motion segments, the inferior discal surface of the upper vertebra manifests more osteophytes than the superior discal surface of the lower one. Osteophytes prevalence is sex-dependent only in the upper cervical vertebrae (C3-C4), and age- and ethnicity-dependent for all vertebrae. Anat Rec, 302:226-231, 2019. © 2018 Wiley Periodicals, Inc.

Human C-reactive protein aggravates osteoarthritis development in mice on a high-fat diet.

OBJECTIVE: C-reactive protein (CRP) levels can be elevated in osteoarthritis (OA) patients. In addition to indicating systemic inflammation, it is suggested that CRP itself can play a role in OA development. Obesity and metabolic syndrome are important risk factors for OA and also induce elevated CRP levels. Here we evaluated in a human CRP (hCRP)-transgenic mouse model whether CRP itself contributes to the development of 'metabolic' OA. DESIGN: Metabolic OA was induced by feeding 12-week-old hCRP-transgenic males (hCRP-tg, n = 30) and wild-type littermates (n = 15) a 45 kcal% high-fat diet (HFD) for 38 weeks. Cartilage degradation, osteophytes and synovitis were graded on Safranin O-stained histological knee joint sections. Inflammatory status was assessed by plasma lipid profiling, flow cytometric analyses of blood immune cell populations and immunohistochemical staining of synovial macrophage subsets. RESULTS: Male hCRP-tg mice showed aggravated OA severity and increased osteophytosis compared with their wild-type littermates. Both classical and non-classical monocytes showed increased expression of CCR2 and CD86 in hCRP-tg males. HFD-induced effects were evident for nearly all lipids measured and indicated a similar low-grade systemic inflammation for both genotypes. Synovitis scores and synovial macrophage subsets were similar in the two groups. CONCLUSIONS: Human CRP expression in a background of HFD-induced metabolic dysfunction resulted in the aggravation of OA through increased cartilage degeneration and osteophytosis. Increased recruitment of classical and non-classical monocytes might be a mechanism of action through which CRP is involved in aggravating this process. These findings suggest interventions selectively directed against CRP activity could ameliorate metabolic OA development.

Joint Space Width, but not Osteophyte Thickness, is a Reliable Indicator of Degeneration of Lateral Knee Joint Cartilage.

In this histologically controlled in vitro study, we evaluated the validity of plain radiography for the assessment of lateral knee joint cartilage degeneration (25 specimens). We examined the correlation between histological grade and radiography findings along with patient demographics. Our study indicated that the Mankin score had a significant inverse correlation with middle joint space width (JSW ; r=-0.19,P=0.02), but not with inner and outer JSW (inner : r=-0.11,P=0.10, outer : r=-0.14,P=0.06) under a non-weight bearing condition. The Mankin score had a significant inverse correlation with middle and outer JSW (middle : r=-0.17,P=0.04, outer : r=-0.14,P=0.04), but not with inner JSW (inner : r=-0.15,P=0.06) under valgus stress. There was no significant correlation between the Mankin score and osteophyte thickness (r=0.004,P=0.76). We also examined the correlation with patient demographics. We found that only the preoperative femorotibial angle had a significant inverse correlation with the Mankin score. These results indicate that JSW, but not osteophyte thickness, is reliable for evaluating lateral femoral cartilage degeneration.

The biomechanical influence of anterior vertebral body osteophytes on the lumbar spine: A finite element study.

BACKGROUND CONTEXT: Anterior vertebral body osteophytes are common with degeneration but their biomechanical influence on the whole lumbar spine remains unclear. PURPOSE: To investigate the biomechanical influence of anterior vertebral body osteophytes on the whole lumbar spine. STUDY DESIGN/SETTING: This is a study using finite element analysis. OUTCOME MEASURES: Intersegmental rotation, maximum Mises stress, and intradiscal pressure on the intervertebral discs of different lumbar levels were calculated. METHODS: A finite element model of an intact lumbar spine was constructed and validated against in vitro studies. The modified models, which had different degrees of anterior vertebral body osteophyte formation (OF) in combination with disc space narrowing, were applied with physiological loadings. RESULTS: The lumbar levels with various degrees of OF altered the kinematics of these levels, which also affected the whole lumbar spine. In flexion and lateral bending, the segment that was one level inferior to the vertebra with OF showed a trend towards increased range of motion. On the intervertebral discs that were one level inferior to the OF level, a trend towards increase in the maximum von Mises stress was found on the annulus. CONCLUSIONS: Segments adjacent to levels with anterior vertebral body osteophytes showed increased intersegmental rotation and maximum stress. Further clinical observation should be performed to verify the results in vivo.

What is the tolerated width of periacetabular osteophytes to avoid impingement in cementless THA?: a three-dimensional simulation study.

BACKGROUNDS: Impingement is a risk factor for instability and prosthetic failure following total hip arthroplasty (THA). If the periacetabular osteophytes are not removed at surgery, impingement could occur between the osteophytes and the femoral stem following THA. However, excessive removal of the osteophytes could lead to bleeding from the bone. The aim of our study, therefore, was to locate the site of the impingement and to determine the width of tolerable osteophytes, which does not induce impingement during activities of daily living (ADL), using a three-dimensional simulation. METHODS: On 35 hip models, virtual THA was performed. The acetabular cups were positioned at 45° abduction and 20° anteversion, and the anteversion of femoral stems was 15°. Circular osteophytes with a 30-mm rim were built around the acetabular cup. Fourteen ADL motions were simulated, and the osteophytes were removed until there was no impingement. A clock face was used to map the location and the width of tolerable osteophytes. RESULTS: The impingement mainly occurred in antero-superior and posterior portions around the acetabular cup. Only 4.2-6.2-mm osteophytes were tolerable at the antero-superior portion (12-3 o'clock) and 6.3-7.2-mm osteophytes at the posterior portion (8-10 o'clock) following a total hip arthroplasty. In antero-inferior and postero-superior portions, over-20-mm osteophytes did not induce any impingement. CONCLUSION: Osteophytes in the antero-superior and posterior portion of the acetabulum should be excised during a THA to avoid impingement of the femur-stem construct on the acetabular osteophytes during ADLs.

Radiographic Predictors of Patient Satisfaction Following Primary Total Knee Arthroplasty.

BACKGROUND: Predicting satisfaction following total knee arthroplasty (TKA) continues to be a clinical challenge. We sought to quantify radiographic variables associated with clinical improvement and satisfaction following TKA. METHODS: We reviewed a consecutive series of primary TKAs performed by a single surgeon with a minimum 2-year follow-up. Radiographic variables assessed included preoperative and postoperative mechanical axis alignment, osteophyte size and location, and the presence of tibial or patella subluxation. Measurements were taken using a calibrated ruler and goniometer using digital radiographs. Knee Society Scores (KSS), satisfaction, and range of motion (ROM) were prospectively collected. RESULTS: A total 155 TKAs were followed with a minimum 2.3 year follow-up (mean: 4.2 ± 0.85). Eleven were not satisfied, 9 were satisfied with minor complaints, and 131 were completely satisfied after TKA. Increasing size of patella and lateral compartment osteophytes, particularly greater than 5 mm, was significantly associated with improvement in KSS knee scores (p < 0.05). Patient satisfaction was also strongly associated with these variables and appeared independent of mechanical axis alignment. A regression model demonstrated that lateral patella osteophytes and lateral compartment osteophytes continued to have a significant.

Ultrasound Diagnosis of Osteophytic Impingement of the Popliteus Tendon After Total Knee Replacement.

We report our experience with 6 patients who had total knee replacements with lateral-sided knee pain, referred for ultrasound (US) assessment and US-guided injection. All cases showed an osteophyte within the popliteus sulcus of the lateral femoral condyle impinging on the adjacent tendon. Five of 6 patients reported improvement of symptoms immediately after US-guided injection of an anesthetic and a steroid. Ultrasound has a unique role in the imaging of knee replacements because of its real-time capabilities and absence of artifacts at the popliteus tendon origin.

Controlling Abnormal Joint Movement Inhibits Response of Osteophyte Formation.

Objective Osteoarthritis (OA) is induced by accumulated mechanical stress to joints; however, little has been reported regarding the cause among detailed mechanical stress on cartilage degeneration. This study investigated the influence of the control of abnormal joint movement induced by anterior cruciate ligament (ACL) injury in the articular cartilage. Design The animals were divided into 3 experimental groups: CAJM group ( n = 22: controlling abnormal joint movement), ACL-T group ( n = 22: ACL transection or knee anterior instability increased), and INTACT group ( n = 12: no surgery). After 2 and 4 weeks, the knees were harvested for digital microscopic observation, soft X-ray analysis, histological analysis, and synovial membrane molecular evaluation. Results The 4-week OARSI scores showed that cartilage degeneration was significantly inhibited in the CAJM group as compared with the ACL-T group ( P < 0.001). At 4 weeks, the osteophyte formation had also significantly increased in the ACL-T group ( P < 0.001). These results reflected the microscopic scoring and soft X-ray analysis findings at 4 weeks. Real-time synovial membrane polymerase chain reaction analysis for evaluation of the osteophyte formation-associated factors showed that the mRNA expression of BMP-2 and VEGF in the ACL-T group had significantly increased after 2 weeks. Conclusions Typically, abnormal mechanical stress induces osteophyte formation; however, our results demonstrated that CAJM group inhibited osteophyte formation. Therefore, controlling abnormal joint movement may be a beneficial precautionary measure for OA progression in the future.

Oral administration of undenatured native chicken type II collagen (UC-II) diminished deterioration of articular cartilage in a rat model of osteoarthritis (OA).

OBJECTIVE: The aim of this study was to determine the ability of undenatured native chicken type II collagen (UC-II) to prevent excessive articular cartilage deterioration in a rat model of osteoarthritis (OA). METHODS: Twenty male rats were subjected to partial medial meniscectomy tear (PMMT) surgery to induce OA. Immediately after the surgery 10 rats received vehicle and another 10 rats oral daily dose of UC-II at 0.66 mg/kg for a period of 8 weeks. In addition 10 naïve rats were used as an intact control and another 10 rats received sham surgery. Study endpoints included a weight-bearing capacity of front and hind legs, serum biomarkers of bone and cartilage metabolism, analyses of subchondral and cancellous bone at the tibial epiphysis and metaphysis, and cartilage pathology at the medial tibial plateau using histological methods. RESULTS: PMMT surgery produced moderate OA at the medial tibial plateau. Specifically, the deterioration of articular cartilage negatively impacted the weight bearing capacity of the operated limb. Immediate treatment with the UC-II preserved the weight-bearing capacity of the injured leg, preserved integrity of the cancellous bone at tibial metaphysis and limited the excessive osteophyte formation and deterioration of articular cartilage. CONCLUSION: Study results demonstrate that a clinically relevant daily dose of UC-II when applied immediately after injury can improve the mechanical function of the injured knee and prevent excessive deterioration of articular cartilage.