Clinical results of arthroscopic tight fibrous band release for adult moderate-to-severe gluteal fibrosis using anterior and posterior portals: a retrospective analysis of 118 consecutive cases.

BACKGROUND: To evaluate the clinical outcomes of arthroscopic tight fibrous band release in the treatment of adult moderate-to-severe gluteal fibrosis using anterior and posterior portals during mid-term follow-up. METHODS: The data of 138 patients (58 males, 80 females) aged between 18 and 42 years (mean, 28.6 years), presenting with bilateral moderate-to-severe gluteal fibrosis (GF) from October 2013 to August 2019, was retrospectively analyzed. All patients underwent arthroscopic tight fibrous band release using anterior and posterior portals with radiofrequency energy. Under arthroscopic guidance through the posterior portal, we debrided the fatty tissue overlying the contracted band of the gluteal muscle and excised the contracted bands using a radiofrequency device introduced through the anterior portal. The pre- and post-operative gluteal muscle contracture disability (GD) scale and the patient satisfaction rate were compared to evaluate the curative effect of the operation. RESULTS: The average operation time was 18 min (range, 10-30 min) and the average blood loss was 4 ml (range, 2-10 ml) for unilateral arthroscopic release. Two cases of post-operative minimal hematomas, 2 cases of bruising and 2 cases of local subcutaneous edema were observed as early complications and were cured by conservative treatment. After surgery, all incisions healed in stage I, and no other complications such as wound infection, nerve and blood vessel injury were detected. One hundred eighteen patients were followed up for 6 to 72 months (mean, 36 months). No lateral instability of the hip was observed and all patients returned to normal gait. The degree of adduction of the hip joint in all these 118 patients was significantly improved relative to their pre-operative conditions. One hundred fifteen patients (97.5%) were able to crouch with knees close to each other after surgery. One hundred fourteen patients (96.6%) were able to cross the affected leg completely without any support. The GD scale was improved from 55.5 ± 10.6 before operation to 90.1 ± 5.2 at the last follow-up (p < 0.05). The patient satisfaction rate was 95.8%. CONCLUSION: Arthroscopic tight fibrous band release using anterior and posterior portals is minimally invasive for adult moderate-to-severe gluteal fibrosis, with a high success rate, quick recovery after surgery and reliable medium-term effect.

Diagnostic and Therapeutic Potential of Exosomal MicroRNAs for Neurodegenerative Diseases.

Neurodegenerative disorders (NDs) are characterized by a gradual loss of neurons and functions that eventually leads to progressive neurological impairment. In view of the heavy burden on the healthcare system, efficient and reliable biomarkers for early diagnosis and therapeutic treatments to reverse the progression of NDs are in urgent need. There has been an increasing interest in using exosomal miRNAs as biomarkers or targeted therapies for neurological diseases recently. In this review, we overviewed the updated studies on exosomal miRNAs as biomarkers and potential therapeutic approaches in NDs, as well as their association with the pathophysiology of this group of disorders, especially Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). The exosomal miRNAs that are commonly dysregulated across different NDs or are commonly used as therapeutic candidates were also identified and summarized. In summary, the feasibility of exosomal miRNAs as biomarkers and potential targeted therapy for NDs has been verified. However, due to the limitations of existing studies and the discrepancies across different studies, high quality laboratory and clinical investigations are still required.

Clinical outcome of arthroscopic internal drainage of popliteal cysts with or without cyst wall resection.

BACKGROUND: This study aimed to compare the arthroscopic internal drainage of popliteal cysts alone or in combination with cyst wall resection in terms of clinical outcomes. METHODS: Forty-two consecutive patients with symptomatic popliteal cysts received arthroscopic treatment. Specifically, 20 of them received arthroscopic internal drainage (AI group) alone and 22 received arthroscopic internal drainage combined with cyst wall resection (AICR group) through double posteromedial portals. Magnetic resonance imaging (MRI) was performed to identify recurrence of popliteal cysts. The Lysholm score and Rauschning-Lindgren grade were used to assess the clinical outcomes. The median of the follow-up period was 24 months (12-48 months). RESULTS: The two groups (AI group and AICR group) were similar in age, gender, cyst diameter, associated joint disorder, preoperative Lysholm score, preoperative Rauschning-Lindgren grade and follow-up period (P > 0.05). Relative to the AI group, the AICR group had a significantly prolonged operation time (P < 0.05) and a higher incidence of complications (P < 0.05). In both groups, the Rauschning-Lindgren grade at the last follow-up significantly differed from the preoperative grade (P < 0.05) and the Lysholm knee score remarkably increased compared to the preoperative score (P < 0.05); however, there were no differences between the two groups at the last follow-up (P > 0.05). According to the MRI results, the cyst disappeared in 11 (55%), shrank in size in 6 (30%) and existed in 3 (15%) patients in the AI group, and was absent in 18 (81.8%) and shrank in size in 4 (18.2%) patients in the AICR group, suggesting a significant difference between the two (P < 0.05). CONCLUSION: Additional resection of cyst wall can result in a lower recurrence rate of cysts but extend the operation time and increase the incidence of perioperative complications compared with arthroscopic internal drainage of popliteal cysts alone.

TGF-b1 or hypoxia enhance glucose metabolism and lactate production via HIF1A signaling in tendon cells.

Purpose/Aim of the study: Healthy tendons are maintained in homeostasis through controlled usage of glucose for energy and redox equilibrium. Tendon cell stress imposed by overuse injury or vascular insufficiency is accompanied by activation of wound healing pathways which facilitate an adaptive response and the restoration of homeostasis. To understand this response at the gene expression level we have studied the in vivo effects of injected TGF-ß1 in a murine model of tendinopathy, as well as treatment of murine tendon explants with either TGF-ß1 or hypoxia in vitro. METHODS AND RESULTS: We provide evidence (from expression patterns and immunohistochemistry) that both in vivo and in vitro, the stress response in tendon cells may be metabolically controlled in part by glycolytic reprogramming. A major feature of the response to TGF-ß1 or hypoxia is activation of the Warburg pathway which generates lactate from glucose under normoxia and thereby inhibits mitochondrial energy production. CONCLUSIONS: We discuss the likely outcome of this major metabolic shift in terms of the potential benefits and damage to tendon and suggest how incorporation of this metabolic response into our understanding of initiation and progression of tendinopathies may offer new opportunities for diagnosis and the monitoring of therapies.

Associations of dietary and serum magnesium with serum high-sensitivity C-reactive protein in early radiographic knee osteoarthritis patients.

INTRODUCTION: This study aimed to examine the associations of dietary magnesium (Mg) intake and serum Mg concentration with the high-sensitivity C-reactive protein (hsCRP) level in early radiographic knee osteoarthritis (OA) patients. METHODS: Multivariable logistic regression was used to test the associations of dietary and serum Mg with the serum hsCRP in early radiographic knee OA patients after adjustment of a number of potential confounding factors. RESULTS: A total of 936 early radiographic knee OA patients were included. A significant association between dietary Mg intake and hsCRP was observed. The multivariable-adjusted odds ratio (OR) (95% CI) for elevated hsCRP (≥3.0 mg/l) in the second, third, fourth, and fifth dietary Mg intake quintile were 0.44 (95% CI: 0.24-0.82), 0.58 (95% CI: 0.31-1.10), 0.34 (95% CI: 0.15-0.77), and 0.19 (95% CI: 0.06-0.57), respectively, compared with the lowest (first) quintile, and p for trend was 0.01. A significant association between serum Mg concentration and hsCRP was observed. The multivariable-adjusted OR (95% CI) for elevated hsCRP in the second, third, fourth, and fifth serum Mg concentration quintile were 0.63 (95% CI: 0.35-1.12), 0.83 (95% CI: 0.50-1.39), 0.53 (95% CI: 0.31-0.91), and 0.46 (95% CI: 0.25-0.85), respectively, compared with the lowest quintile, and p for trend was 0.01. CONCLUSION: The present study indicated that both dietary and serum Mg were inversely associated with serum hsCRP in early radiographic knee OA patients.

Association between high-sensitivity C-reactive protein and hyperuricemia.

The aim of the study was to examine the cross-sectional association between high-sensitivity C-reactive protein (hsCRP) and hyperuricemia (HU). The hsCRP was measured by latex turbidity method. Uric acid was detected on Beckman Coulter AU 5800. HU was defined as uric acid ≥416 µmol/L for the male population and ≥360 µmol/L for the female population. A multivariable logistic analysis model was applied to test the association after adjusting for a number of potential confounding factors. A total of 1935 subjects were included in this study. According to the multivariable regression model, the relative odds of the prevalence of HU were increased by 0.56 times in the third quintile (OR 1.56, 95 % CI 1.03-2.38, P = 0.04), 0.55 times in the fourth quintile (OR 1.55, 95 % CI 1.01-2.36, P = 0.04) and 0.96 times in the fifth quintile (OR 1.96, 95 % CI 1.29-2.98, P < 0.01) of hsCRP comparing with the lowest quintile, and P for trend was smaller than 0.01. In the male population, a positive association existed in the highest quintile of hsCRP (OR 1.66, 95 % CI 1.04-2.66, P = 0.04), and P for trend was 0.07. In the female population, the multivariable-adjusted ORs (95 % CI) of HU in the fourth and fifth quintile of hsCRP were 3.02 (95 % CI 1.09-8.35, P = 0.03) and 3.66 (95 % CI 1.36-9.89, P = 0.01), respectively, and P for trend was smaller than 0.01. The findings of this cross-sectional study suggest that the hsCRP level is positively associated with the prevalence of HU. Level of evidence Cross-sectional study, Level III.

The associations of serum uric acid level and hyperuricemia with knee osteoarthritis.

To examine the cross-sectional associations of the serum uric acid level and hyperuricemia (HU) with the radiographic features of osteoarthritis (OA), including osteophytes (OST) and joint space narrowing (JSN), a total of 4685 subjects were included in this study. Blood samples were drawn from all subjects. Serum uric acid and some other indexes were detected. OST and JSN were assessed for each subject according to the Osteoarthritis Research Society International (OARSI) atlas. A multivariable logistic analysis model was applied to test the target associations after adjusting a number of potential confounding factors. The prevalence of OST was increased in the highest tertile of uric acid compared to the lowest in female subjects (OR 1.46, 95 % CI 1.07-1.99, P for trend = 0.02). Meanwhile, a positive association between OST and HU was observed in female subjects (OR 1.43, 95 % CI 1.01-2.03, P = 0.05). However, serum uric acid and HU were not significantly associated with JSN in male subjects. The findings of this study indicated that the serum uric acid concentration and prevalence of HU are positively associated with OST of the knee in the female population. Level of evidence Cross-sectional study, Level III.

Relationship between soy milk intake and radiographic knee joint space narrowing and osteophytes.

The purpose of this study was to examine the cross-sectional association between dietary soy milk intake and the prevalence of radiographic knee joint space narrowing (JSN) and osteophytes (OST). Soy milk intake was assessed using a validated semiquantitative food frequency questionnaire and classified into three categories: never,

Autograft Versus Allograft in Anterior Cruciate Ligament Reconstruction: A Meta-analysis of Randomized Controlled Trials and Systematic Review of Overlapping Systematic Reviews.

PURPOSE: To compare autograft with allograft in anterior cruciate ligament reconstruction by conducting a meta-analysis of randomized controlled trials (RCTs) and a systematic review of overlapping systematic reviews. METHODS: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched through June 28, 2014, to identify Level I and II evidence RCTs with a minimum follow-up of 2 years and systematic reviews that compared autograft with allograft in anterior cruciate ligament reconstruction. Both objective and subjective outcomes with respect to knee stability and function were meta-analyzed and summarized. The overall risk ratio (RR) or the weighted mean difference (WMD) was calculated using either a fixed- or random-effects model. The quality of evidence of the systematic review of overlapping systematic reviews was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. RESULTS: Nine RCTs and 10 systematic reviews were included. In general, statistically significant differences in favor of autograft were observed for clinical failure (RR, 0.47; P = .0007), the Lachman test (RR, 1.18; P = .03), the instrumented laxity test (WMD, -0.88; P = .004), and the Tegner score (WMD, 0.36; P = .004). When subgroup analyses were conducted based on whether irradiation was used, autograft achieved better clinical outcomes than irradiated allograft in terms of the Lysholm score, clinical failure, the pivot-shift test, the Lachman test, the instrumented laxity test, and the Tegner score. In addition, there were no significant differences between the autograft and nonirradiated allograft groups for all 8 indices. The final results of this systematic review of overlapping systematic reviews were in accordance with our meta-analysis. CONCLUSIONS: Autograft had greater advantages than irradiated allograft with respect to function and stability, whereas there were no significant differences between autograft and nonirradiated allograft. LEVEL OF EVIDENCE: Level IV, meta-analysis of Level II, III, and IV studies.

Is posterior tibial slope associated with noncontact anterior cruciate ligament injury?

PURPOSE: This study aimed to: (1) examine whether the association between posterior tibial slope and noncontact ACL injury exists in Chinese population; (2) compare the reliability and consistency of the three methods (longitudinal axis, posterior and anterior tibial cortex axis) in lateral radiograph. METHODS: Case-control study contained 146 patients in total (73 noncontact ACL injuries and 73 meniscus injuries, matched for age and gender), which were verified by arthroscopy, MRI and physical examination. RESULTS: For the total population and the male subgroup, the mean posterior tibial slope of the ACL-injured group was significantly higher than that of the control group (P < 0.001). In addition, the longitudinal axis method exhibited the highest inter-rater (0.898) and intrarater reliability (0.928), whereas the anterior tibial cortex was the most variable (inter-rater reliability, 0.805; intrarater reliability, 0.824). The anterior tibial cortex method produced largest posterior tibial slope measurements (13.8 ± 3.3 for injury group; 11.6 ± 2.7 for control group), while the posterior tibial cortex method was the smallest (9.1 ± 3.1 for injury group; 7.2 ± 2.6 for control group). All three methods were not affected by age, sex, height, weight and BMI (n.s.). CONCLUSIONS: The results of this study suggested that an increased posterior tibial slope was associated with the risk of noncontact ACL injury in Chinese population. Meanwhile, the longitudinal axis method is recommended for measuring posterior tibial slope in lateral radiograph in future studies. Posterior tibial slope measured by longitudinal axis method may be used as predictor of ACL injury. LEVEL OF EVIDENCE: Case-control study, Level III.

The influence of the tibial plateau slopes on injury of the anterior cruciate ligament: a meta-analysis.

PURPOSE: The purpose of this meta-analysis was (1) to examine the effect of the tibial plateau slopes (medial and lateral) on anterior cruciate ligament (ACL) injury and (2) to investigate gender differences between ACL-injured subjects and gender-matched controls. METHODS: The PubMed database was searched through to 1 November 2011 to identify studies that met pre-stated inclusion criteria. Reference lists of retrieved articles were also reviewed. Two authors independently extracted information on the designs of the studies, the characteristics of the study participants, exposure and outcome assessments, and control for potential confounding factors. A meta-analysis was conducted, and either a fixed- or a random-effects model was used to calculate the overall weighted mean difference (WMD). RESULTS: Twelve studies (n = 1,871: 923 patients in the ACL-injured group and 938 patients in the control group) were included. The medial tibial plateau slope in the ACL group ranged from 1.8° ± 3.7° to 12.1° ± 3.3° while it ranged from 2.9° ± 2.8° to 9.5° ± 3° among the controls. The lateral tibial plateau slope in the ACL ranged from 1.8° ± 3.2° to 11.5° ± 3.5° and 0.3° ± 3.6° to 9° ± 4° in the control group. Statistically significant increased angles were observed in ACL-injured group compared to control group for medial tibial plateau slope (WMD, 1.1°; 95 % confidence interval, 0.5°-1.7°) and lateral tibial plateau slope (WMD, 1.8°; 95 % confidence interval, 1.3°-2.3°). Sensitivity analysis and subgroup analysis proved this to be a reliable result. CONCLUSIONS: The current meta-analysis suggests that both, increased medial and lateral tibial plateau slopes, are associated with increased susceptibility to ACL injury regardless of gender. In addition, this study indicates a stronger evidence for lateral tibial plateau slope to be associated with ACL injury compared with medial tibial plateau slope due to the larger increased angle value and on the basis of consistency among the included studies.

Physeal-Sparing, All-Inside Anterior Cruciate Ligament Reconstruction Using Quadrupled Semitendinosus Autograft and Suture Tape Augmentation for Skeletally Immature Patients.

The anterior cruciate ligament (ACL) is the primary soft-tissue structure for anterior stabilization of the knee and is one of the most frequently injured structures. The incidence of ACL injuries in children and adolescents ranges from 92 to 151 per 100,000 person-years. The choice of surgical treatment for this population group is controversial, with a widespread concern that adult reconstruction techniques may damage the epiphyseal plate, compromise growth, or cause deformity. In this article, we describe a physeal-sparing, all-inside ACL reconstruction technique for skeletally immature patients. This technique is supported by retrograde drilling of the femoral tunnel and retrograde drilling of the tibial tunnel, both of which are able to avoid the epiphyseal growth line. Fixation of the quadrupled semitendinosus autograft and suture tape augmentation are achieved by soft-tissue buttons on the femur and tibia. The surgical details of this reproducible reconstruction technique are elaborated.

Preferences in anterior cruciate ligament reconstruction: A survey among orthopedic surgeons in China.

The purpose of this study was to reveal the current trends and preferences of Chinese orthopedic surgeons regarding anterior cruciate ligament (ACL) reconstruction through a nationwide web-based survey conducted in China. The survey questionnaire was distributed via WeChat to the chairmen of provincial orthopedic and sports medicine organizing committees in China, who then shared it in their respective WeChat workgroups. The questionnaire consisted of 52 multiple-choice questions covering 8 sections. Data collection was implemented by Questionnaire Star. A total of 812 valid questionnaires were returned: 94.21% of the respondents preferred single-bundle reconstruction of ACL, while 61.70% preferred autogenous semitendinosus plus gracilis reconstruction; 76.35% of the respondents preferred establishing the femoral tunnel first, while 47.29% preferred establishing the femoral tunnel through a medial auxiliary approach; and 85.10% of the respondents recommended patients to undergo surgery within 3 months after ligament injury. Besides, the vast majority of respondents chose to retain the ligamentous remnant bundle (92.98%) and recommended routine use of knee braces postoperatively (94.09%). It is recommended to perform arthroscopic single-bundle ACL reconstruction with the remnant preserving technique using a hamstring autograft within 3 months of ACL rupture, with support of postoperative functional braces.

Interposition Grafting Using Fascia Lata Autograft for Failed Rotator Cuff Repairs.

Massive rotator cuff tears are a huge challenge for orthopaedic surgeons, as the patients may be in need of multiple operations, even including reverse total shoulder arthroplasty. The various repair methods for the rotator cuff, such as partial rotator cuff repair, patch-augmented rotator cuff repair, bridging rotator cuff reconstruction with graft interposition, tendon transfer, and superior capsular reconstruction, have always been the focus of research. During surgical intervention for failed rotator cuff repairs, complexity of tears, poor tissue quality, retained hardware, and adhesions are the problems routinely encountered. In this Technical Note, we describe the technique of interposition grafting using fascia lata autograft to reconstruct the rotator cuff after failed primary repair.

Anterior Shoulder Stabilization Using Single Needle-Assisted Outside-In Remplissage Technique and Bankart Repair.

Arthroscopic repair of Bankart injury is the first choice for the treatment of anterior shoulder instability. How to avoid recurring shoulder joint dislocation is a challenge, especially when combined with Hill-Sachs lesions. The arthroscopy technology allows for broader vision and less surgical trauma but is limited by a smaller operating space. At present, extensive descriptions about the surgical procedure of arthroscopic Bankart repair have been published. In this Technical Note, we describe the use of remplissage filling with Hill-Sachs lesion combined with Bankart repair to further improve the surgical accuracy and clinical efficacy. In particular, the application of single needle-assisted outside-in remplissage technique and Bankart repair is introduced in detail.

The effect of hyaluronic acid on osteopontin and CD44 mRNA of fibroblast-like synoviocytes in patients with osteoarthritis of the knee.

The aim of this study was to investigate the effect of hyaluronic acid (HA) on the expression of osteopontin (OPN) and CD44 mRNA of fibroblast-like synoviocytes (FLS) in the patients with osteoarthritis (OA) of the knee. FLS were obtained from the knees of 10 patients with OA. Real-time quantitative polymerase chain reaction (Q-PCR) was used to assess the expression of the OPN mRNA and CD44 mRNA. The relative OPN mRNA expression in HA group (6.47 ± 2.30-fold) was significantly higher than in the control group (P = 0.045, P < 0.05), while in HYL group (0.65 ± 0.21-fold) it was lower than in the control group (P = 0.037, P < 0.05), and the difference in OPN mRNA expression between HA group and HYL group also showed statistically significant (P = 0.001, P < 0.05); however, there was no significant difference between each group of the relative CD44 mRNA expression (P > 0.05). Our study showed that HA can upregulate OPN mRNA expression in OA fibroblast-like synoviocytes, and the high expression of OPN mRNA in OA may be a result of increased HA level of OA synovitis; however, HA cannot affect the CD44 mRNA expression in OA fibroblast-like synoviocytes, and the high expression of CD44 mRNA in OA may be not a result of increased HA level of OA synovitis.

Single-dose intra-articular morphine after arthroscopic knee surgery: a meta-analysis of randomized placebo-controlled studies.

PURPOSE: The purpose of this quantitative meta-analysis is to appraise the efficacy and side effects of intra-articular morphine in patients undergoing arthroscopic knee surgery. METHODS: The comprehensive literature search, using Medline (1966 to 2013), the Cochrane Central Register of Controlled Trials, and EMBASE databases, was conducted to identify randomized placebo-controlled trials that used single-dose intra-articular morphine for postoperative pain. The relative risk (RR), standardized mean difference (SMD), and their corresponding 95% confidence intervals (CIs) were calculated using statistical software. RESULTS: Twenty-six articles were included in the meta-analysis. The acute postoperative visual analog scale (VAS) pain scores of the morphine group compared with the control group were significantly lower (SMD, -1.16; 95% CI, -1.79 to -0.53; P = .0003). The number of patients requiring supplementary analgesia was also significantly reduced (RR, 0.80; 95% CI, 0.70 to 0.93; P = .008), and there was a significant difference in the time to first analgesic request (SMD, 1.47; 95% CI, 0.49 to 2.44; P = .003) when the morphine group was compared with the placebo group. However, there was no significant difference in side effects between the morphine group and the control group (RR, 0.93; 95% CI, 0.67 to 1.28; P = .65). CONCLUSIONS: The key findings of the present study were that the administration of single-dose intra-articular morphine at the end of arthroscopic knee surgery provided better pain relief, reduced the need for supplementary analgesics, and lengthened the time interval before the first request for additional analgesic medication, all with short-term side effects similar to those of the saline placebo. LEVEL OF EVIDENCE: Level II, meta-analysis of Level I-II studies.

The influence of the intercondylar notch dimensions on injury of the anterior cruciate ligament: a meta-analysis.

PURPOSE: The aim of this meta-analysis was to examine the effect of the intercondylar notch dimensions, intercondylar notch width index (NWI) and intercondylar notch width (NW), separately in anterior cruciate ligament (ACL) injury. METHODS: The PubMed and Wanfang database were searched through until 1 November 2011 to identify studies that met pre-stated inclusion criteria. Reference lists of retrieved articles were also reviewed. Two authors independently extracted information on the designs of the studies, the characteristics of the study participants, exposure and outcome assessments and control for potential confounding factors. Either a fixed- or a random-effects model was used to calculate the overall weighted mean difference (WMD). RESULTS: Sixteen studies (n = 4,291) were included (1,222 subjects in ACL-injured group and 3,069 subjects in the control group). Statistically significant differences were observed in the NWI (WMD, -0.02; 95 % confidence interval, -0.04 to -0.01), and in the NW (WMD, -2.15; 95 % confidence interval, -3.09 to -1.21) among the ACL-injured group when compared to the control group. CONCLUSION: The meta-analysis findings concluded that narrow intercondylar notch dimensions were associated with the risk of ACL injury. A lower NWI or NW stenosis predisposes an individual to ACL injury. Further original studies should include more anatomical risk factors that could be associated with the risk of ACL injury.

Expression of CD44 in articular cartilage is associated with disease severity in knee osteoarthritis.

OBJECTIVES: To investigate CD44 levels in articular cartilage of knee osteoarthritis (OA) and the relationship between CD44 and severity of the disease. METHODS: All 50 cartilage tissues included normal and OA cartilage, and were ascribed to the following four groups on the basis of modified Mankin score: normal, mild lesions, moderate lesions and severe lesions. CD44 levels in articular cartilage were assessed by immunohistochemical methods. RESULTS: CD44 levels were detected in all four groups. The difference in average gray value of CD44 expression showed statistical significance when compared between each group (P < 0.05). In addition, CD44 expression in each group correlated with disease severity, according to the modified Mankin score (ρ = -0.848, P < 0.01). CONCLUSIONS: CD44 in articular cartilage is associated with progressive knee OA joint damage.