Prevalence of osteoporosis in patients awaiting total hip arthroplasty

Short-term exposure to gaseous pollutants is neglected factors for knee osteoarthritis: evidence from a humid subtropical region of China

Few studies were performed on the impact of exposure to gaseous pollutants on the risk of knee osteoarthritis (KOA). We conducted this study to analyze the association between short-term exposure to gaseous pollutants and the risk of hospitalizations for KOA. A total of 2952 KOA hospitalizations derived from two hospitals in Hefei, and the relationship between gaseous pollutants and KOA hospitalizations was analyzed by a distributed lag non-linear model combined with a generalized linear model. We found that the decreased risk of hospitalizations for KOA were both related to exposure to NO2 (RR = 0.993, lag19 day) and O3 (RR = 0.984, lag0 day), while exposure to CO could increase the risk of hospitalizations for KOA (RR = 1.076, lag2 day). Stratified analyses suggested that the KOA patients < 65 years were more susceptible to O3 exposure, and the female, male, patients ≥ 65 years, and patients < 65 years were both more sensitive to CO exposure. Our findings demonstrated that exposure to NO2, O3 resulted in a decreased risk for KOA hospitalizations, and CO exposure might increase the risk of KOA hospitalizations.

A call to "own the bone": osteoporosis is a predictor for adverse two-year outcomes following total hip and knee arthroplasty

PURPOSE

While bone health is instrumental in orthopedic surgery, few studies have described the long-term outcomes of osteoporosis (OP) in patients undergoing total hip (THA) or knee (TKA) arthroplasties.

METHODS

Using the New York State statewide planning and research cooperative system database, all patients who underwent primary TKA or THA for osteoarthritis from 2009 to 2011 with minimum 2-year follow-up were identified. They were divided based on their OP status (OP and non-OP) and 1:1 propensity score matched for age, sex, race, and Charlson/Deyo index. Cohorts were compared for demographics, hospital-related parameters, and 2-year postoperative complications and reoperations. Multivariate binary logistic regression was utilized to identify significant independent associations with 2-year medical and surgical complications and revisions.

RESULTS

A total of 11,288 TKA and 8248 THA patients were identified. OP and non-OP TKA patients incurred comparable overall hospital charges for their surgical visit and hospital length of stay (LOS) (both, p ≥ 0.125). Though OP and non-OP THA patients incurred similar mean hospital charges for their surgical visit, they experienced longer hospital LOS (4.3 vs. 4.1 days, p = 0.035). For both TKA and THA, OP patients had higher rates of overall and individual medical and surgical complications (all, p < 0.05). OP was independently associated with the 2-year occurrence of any overall, surgical, and medical complications, and any revision in TKA and THA patients (all, OR ≥ 1.42, p < 0.001).

CONCLUSION

Our study found OP was associated with a greater risk of 2-year adverse outcomes following TKA or THA, including medical, surgical, and overall complications as well as revision operations compared to non-OP patients.

The effect of reduced bone mineral density on elective total hip arthroplasty outcomes

INTRODUCTION

Reduced bone mineral density (BMD) and disruption of normal bony architecture are the characteristics of osteopenia and osteoporosis and in patients undergoing total hip arthroplasty (THA) may cause failure of trabecular ingrowth. The purpose of this study is to evaluate the impact of reduced BMD on outcomes following primary elective THA.

METHODS

A retrospective chart review of 650 elective THAs with a DEXA scan in their electronic health record (EHR) from 2011 to 2020 was conducted at an urban, academic center and a regional, health center. Patients were separated into three cohorts based on their t-score and the World Health Organizations definitions: normal (t-score ≥ - 1), osteopenia (t-score < - 1.0 and > - 2.5), and osteoporosis (t-score ≤ - 2.5). Demographic and outcome data were assessed. Subsidence was assessed for patients with non-cemented THAs. Regression models were used to account for demographic differences.

RESULTS

650 elective THAs, of which only 11 were cemented, were included in the study. Patients with osteopenia and osteoporosis were significantly older than those without (p = 0.002 and p < 0.0001, respectively) and had a lower BMI (p < 0.0001 and p < 0.0001, respectively). PFx was significantly greater in patients with osteoporosis when compared to those with normal BMD (6.5% vs. 1.0%; p = 0.04). No such difference was found between osteoporotic and osteopenic patients. The revision rate was significantly higher for osteoporotic patients than osteopenic patients (7.5% vs. 1.5%; p = 0.04). No such difference was found between the other comparison groups.

CONCLUSION

Patients with osteoporosis were older with reduced BMI and had increased PFx after non-cemented elective THA. Understanding this can help surgeons formulate an appropriate preoperative plan for the treatment of patients with osteoporotic bone undergoing elective THA.

Osteoporosis in Indian Patients Undergoing Elective Arthroplasty and Spinal Procedures: An Observational Study

Background This is an observational study conducted to determine the prevalence of osteoporosis and osteopenia in patients undergoing elective arthroplasty and spinal procedures in India. Methods This observational, multicentre study included both male and female patients. Their bone mineral density and fracture risk were measured using dual-energy x-ray absorptiometry (DEXA) and Fracture Risk Assessment Tool (FRAX®: Centre for Metabolic Bone Diseases, University of Sheffield, UK), respectively, in compliance with the guidelines for Good Epidemiological Practice (ISRCTN: 14543098). Results The study revealed that majority (76.4%; 97/127) of the patients had low BMD; over one-third had osteoporosis (39.4%; 50/127) or osteopenia (37%; 47/127). Among those undergoing total knee replacement (TKR)/total hip replacement (THR), majority (75.6%; 59/78) had low BMD (osteoporosis: 38.5% {30/78}; osteopenia: 37.2% {29/78}). Among the patients undergoing spinal procedures, all except two (93.10%; 27/29) had low BMD, two-thirds had osteoporosis (65.5%; 19/29), and around one-fourth had osteopenia (27.6%; 8/29). Radial BMD measurements showed higher prevalence of osteoporosis and osteopenia. Based on FRAX score, nearly 30% of patients were at a high risk of hip fracture in the next 10 years. As per National Osteoporosis Foundation (NOF) guidelines, most (59.79%; 58/97) patients with osteoporosis/osteopenia met criteria for pharmacological treatment. Conclusions Regular preoperative bone health evaluation should be adopted and osteoporosis/osteopenia patients should be adequately managed pharmacologically in India.

Prevalence and treatment rate of osteoporosis in patients undergoing total knee and hip arthroplasty: a systematic review and meta-analysis

PURPOSE

Due to age and gender, patients awaiting total knee or hip arthroplasty (TKA/THA) are at a higher risk of osteoporosis. In joint arthroplasty, low bone mineral density (BMD) is a risk factor for implant osseointegration, durability, and prosthesis complications. This study aims to investigate the prevalence and treatment rate of osteoporosis in patients undergoing total joint arthroplasty (TJA).

METHODS

We applied a comprehensive literature search through PubMed, Cochrane Library, and EMBASE from inception to July 10, 2021, for studies investigating the prevalence and treatment rate of osteoporosis in TJA patients. The aggregated prevalence was calculated with the random-effects model, and the heterogeneity between studies was checked by Cochran's Q test and quantified by the I² statistic. We performed subgroup analyses and meta-regression analyses to determine the source of heterogeneity. Publication bias was assessed by a funnel plot and verified by Egger's test. Anti-osteoporosis treatment for TJA patients was described qualitatively and quantitatively.

RESULTS

Of 4561 citations identified by the search strategy, 11 studies including 3462 patients were eligible for inclusion. The pooled prevalence of osteoporosis and osteopenia in TJA patients was 24.8% (95%CI: 14.1-37.2%) and 38.5% (95%CI: 29.3-48.0%), respectively. The prevalence of osteoporosis/osteopenia in TJA patients was 64.0% (95%CI: 45.8-80.3%). In terms of gender, the pooled prevalence of osteoporosis in males, females, and postmenopausal females were 5.5% (95%CI: 1.5-11.4%), 29.0% (95%CI: 18.3-41.1%), and 38.3% (95%CI: 13.2-67.1%), respectively. The treatment rate of osteoporosis in TJA patients was 32.9% (95%CI: 15.2-53.1%) by a random-effects model.

CONCLUSIONS

Osteoporosis is highly prevalent in patients undergoing TJA, especially in postmenopausal females. However, the treatment rate of osteoporosis is low. Considering the possibility of surgical complications, clinicians should strengthen their awareness of pre-operative BMD assessment and manage osteoporosis in high-risk patients.

Trabecular bone porosity and pore size distribution in osteoporotic patients - A low field nuclear magnetic resonance and microcomputed tomography investigation

The study of bone morphology is of great importance as bone morphology is influenced by factors such as age and underlying comorbidities and is associated with bone mechanical properties and fracture risk. Standard diagnostic techniques used in bone disease, such as Dual-Energy X-ray absorptiometry and ultrasonography do not provide qualitative and quantitative morphological information. In recent years, techniques such as High Resolution Computed Tomography (HR-CT), micro- CT, Magnetic Resonance Imaging (MRI), and Low Field Nuclear Magnetic Resonance (LF-NMR) have been developed for the study of bone structure and porosity. Data obtained from these techniques have been used to construct models to predict bone mechanical properties thanks to finite element analysis. Cortical porosity has been extensively studied and successfully correlated with disease progression and mechanical properties. Trabecular porosity and pore size distribution, however, have increasingly been taken into consideration to obtain a comprehensive analysis of bone pathology and mechanic. Therefore, we have decided to evaluate the ability of micro- CT (chosen for its high spatial resolving power) and LF-NMR (chosen to analyze the behavior of water molecules within trabecular bone pores) to characterize the morphology of trabecular bone in osteoporosis. Trabecular bone samples from human femoral heads collected during hip replacement surgery were from osteoporosis (test group) and osteoarthritis (control group) patients. Our data show that both micro- CT and LF-NMR can detect qualitative changes in trabecular bone (i.e., transition from plate-like to rod-like morphology). Micro- CT failed to detect significant differences in trabecular bone morphology parameters between osteoporotic and osteoarthritic specimens, with the exception of Trabecular Number and Connectivity Density, which are markers of osteoporosis progression. In contrast, LF-NMR was able to detect significant differences in porosity and pore size of trabecular bone from osteoporotic versus osteoarthritic (control) samples. However, only the combination of these two techniques allowed the detection of structural morphometric changes (increase in the larger pore fraction and enlargement of the larger pores) in the trabecular bone of osteoporotic specimens compared to osteoarthritic ones. In conclusion, the combined use of LF-NMR and micro- CT provides a valuable tool for characterizing the morphology of trabecular bone and may offer the possibility for a new approach to the study and modeling of bone mechanics in the context of aging and disease.

Impact of Exposure to Ambient Fine Particulate Matter Pollution on Adults with Knee Osteoarthritis

The impact of exposure to fine particulate matter (PM_2.5) on the incidence of knee osteoarthritis is unclear, especially in Beijing which is a highly polluted city. We conducted a time-series study to examine the correlation between PM_2.5 exposure and outpatient visits for knee osteoarthritis in Beijing. Changes (in percentage) in the number of outpatient visits corresponding to every 10-μg/m³ increase in the PM_2.5 concentration were determined using a generalized additive quasi-Poisson model. There were records of 9,797,446 outpatient visits for knee osteoarthritis in the study period from 1 January 2010 to 31 December 2017. The daily concentration of PM_2.5 was 86.8 (74.3) μg/m³ over this period. A 10-μg/m³ increase in PM_2.5 concentrations on lag days 0–3 was associated with a 1.41% (95% confidence interval: 1.40–1.41%) increase in outpatient visits for knee osteoarthritis. Females and patients aged above 65 years were more sensitive to the adverse effects of PM_2.5 exposure. The present findings demonstrate that short-term exposure to PM_2.5 resulted in an increase in the number of outpatient visits for knee osteoarthritis in Beijing. The findings shed light on the effects of air pollution on knee osteoarthritis and could guide risk-mitigating strategies in cities such as Beijing.

[Characteristics of geriatric and somatic status in patients with osteoporosis]

BACKGROUND

Older adults with osteoporosis (OP) and high risk of falls are the most vulnerable group of patients with respect to the development of fractures. Falls and fractures in elderly patients with OP are associated with geriatric syndromes and worse functional status.

AIM

To аssess comorbidity and geriatric status in elderly and senile patients with and without OP.

MATERIALS AND METHODS

The study included 607 patients over 60 years of age hospitalized in the geriatric department. According to the presence of OP, the patients were divided into 2 groups: group 1 - patients with OP (n=178, 29.3%), group 2 - patients without OP (n=429, 70.7%). All patients underwent a general clinical study, an assessment of comorbidity -according to the Charlson index, and a comprehensive geriatric score.

RESULTS

OPs had 178 (29.3%) patients, more often these were women. 55.6% of patients with OP were disabled. Age--related diseases such as Alzheimer's disease, Parkinson's disease, osteoarthritis, anemia, thyroid disease, varicose veins were significantly more common in patients with OP. With almost all of these diseases, a univariate analysis revealed an association with OP. Geriatric syndromes such as frailty, hypodynamia, malnutrition, polypharmacy, urinary incontinence were significantly more common in group 1 patients. Patients with OP were more likely to live alone and use mobility aids compared to patients without OP.The univariate analysis demonstrated that OP is associated (OR 1.54 to 2.00) with frailty, hypodynamia, the use of aids in movement, sleep disorders, sensory vision deficiency, urinary incontinence. The Functional status of patients with OP was worse compared to patients without OP. Patients with OP suffered more fractures, and vertebral fractures were significantly more frequent.

CONCLUSION

Patients with OP have a high comorbidity, a burdened geriatric status. In elderly patients, it is necessary not only to screen and diagnose OP, to assess the risk of 10-years probability of major pathological fractures using the FRAX algorithm, but also to conduct a comprehensive geriatric assessment to diagnose geriatric syndromes that weaken the course of OP and lead to more serious consequences.

Comparison of diclofenac with apigenin-glycosides rich Clinacanthus nutans extract for amending inflammation and catabolic protease regulations in osteoporotic-osteoarthritis rat model

BACKGROUND

Osteoporotic-osteoarthritis is an incapacitating musculoskeletal illness of the aged.

OBJECTIVES

The anti-inflammatory and anti-catabolic actions of Diclofenac were compared with apigenin-C-glycosides rich Clinacanthus nutans (CN) leaf extract in osteoporotic-osteoarthritis rats.

METHODS

Female Sprague Dawley rats were randomized into five groups (n = 6). Four groups were bilateral ovariectomised for osteoporosis development, and osteoarthritis were induced by intra-articular injection of monosodium iodoacetate (MIA) into the right knee joints. The Sham group was sham-operated, received saline injection and deionized drinking water. The treatment groups were orally given 200 or 400 mg extract/kg body weight or 5 mg diclofenac /kg body weight daily for 28 days. Articular cartilage and bone changes were monitored by gross and histological structures, micro-CT analysis, serum protein biomarkers, and mRNA expressions for inflammation and catabolic protease genes.

RESULTS

HPLC analysis confirmed that apigenin-C-glycosides (shaftoside, vitexin, and isovitexin) were the major compounds in the extract. The extract significantly and dose-dependently reduced cartilage erosion, bone loss, cartilage catabolic changes, serum osteoporotic-osteoarthritis biomarkers (procollagen-type-II-N-terminal-propeptide PIINP; procollagen-type-I-N-terminal-propeptide PINP; osteocalcin), inflammation (IL-1β) and mRNA expressions for nuclear-factor-kappa-beta NF-κβ, interleukin-1-beta IL-1β, cyclooxygenase-2; and matrix-metalloproteinase-13 MMP13 activities, in osteoporotic-osteoarthritis rats comparable to Diclofenac.

CONCLUSION

This study demonstrates that apigenin-C-glycosides at 400 mg CN extract/kg (about 0.2 mg apigenin-equivalent/kg) is comparable to diclofenac in suppressing inflammation and catabolic proteases for osteoporotic-osteoarthritis prevention. Graphical abstract.

Biomechanics of Implant Fixation in Osteoporotic Bone

PURPOSE OF REVIEW

The purpose of this review is to critically evaluate the current literature regarding implant fixation in osteoporotic bone.

RECENT FINDINGS

Clinical studies have not only demonstrated the growing prevalence of osteoporosis in patients undergoing total joint replacement (TJR) but may also indicate a significant gap in screening and treatment of this comorbidity. Osteoporosis negatively impacts bone in multiple ways beyond the mere loss of bone mass, including compromising skeletal regenerative capacity, architectural deterioration, and bone matrix quality, all of which could diminish implant fixation. Recent findings both in preclinical animal models and in clinical studies indicate encouraging results for the use of osteoporosis drugs to promote implant fixation. Implant fixation in osteoporotic bone presents an increasing clinical challenge that may be benefitted by increased screening and usage of osteoporosis drugs.

Prevalence of osteoporosis and osteopenia diagnosed using quantitative CT in 296 consecutive lumbar fusion patients

OBJECTIVE

Osteoporosis is a metabolic bone disease that increases the risk for fragility fractures. Screening and diagnosis can be achieved by measuring bone mineral density (BMD) using quantitative CT tomography (QCT) in the lumbar spine. QCT-derived BMD measurements can be used to diagnose osteopenia or osteoporosis based on American College of Radiology (ACR) thresholds. Many reports exist regarding the disease prevalence in asymptomatic and disease-specific populations; however, osteoporosis/osteopenia prevalence rates in lumbar spine fusion patients without fracture have not been reported. The purpose of this study was to define osteoporosis and osteopenia prevalence in lumbar fusion patients using QCT.

METHODS

A retrospective review of prospective data was performed. All patients undergoing lumbar fusion surgery who had preoperative fine-cut CT scans were eligible. QCT-derived BMD measurements were performed at L1 and L2. The L1-2 average BMD was used to classify patients as having normal findings, osteopenia, or osteoporosis based on ACR criteria. Disease prevalence was calculated. Subgroup analyses based on age, sex, ethnicity, and history of abnormal BMD were performed. Differences between categorical groups were calculated with Fisher's exact test.

RESULTS

Overall, 296 consecutive patients (55.4% female) were studied. The mean age was 63 years (range 21-89 years). There were 248 (83.8%) patients with ages ≥ 50 years. No previous clinical history of abnormal BMD was seen in 212 (71.6%) patients. Osteopenia was present in 129 (43.6%) patients and osteoporosis in 44 (14.9%). There were no prevalence differences between sex or race. Patients ≥ 50 years of age had a significantly higher frequency of osteopenia/osteoporosis than those who were < 50 years of age.

CONCLUSIONS

In 296 consecutive patients undergoing lumbar fusion surgery, the prevalence of osteoporosis was 14.9% and that for osteopenia was 43.6% diagnosed by QCT. This is the first report of osteoporosis disease prevalence in lumbar fusion patients without vertebral fragility fractures diagnosed by QCT.

Raloxifene Prevents Early Periprosthetic Bone Loss for Postmenopausal Women after Uncemented Total Hip Arthroplasty: A Randomized Placebo-Controlled Clinical Trial

OBJECTIVE

To examine the results of raloxifene for prevention of periprosthetic bone loss around the femoral stem in patients undergoing total hip arthroplasty (THA).

METHODS

Between January 2015 and May 2017, 240 female patients between 55 and 80 years underwent primary THA and were randomly allocated to receive 60 mg raloxifene hydrochloride per day (treatment group, TG, n = 120) or placebo (control group, CG, n = 120) orally at bedtime using computer-generated randomization sequence generation. Baseline data, the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), women's quality of life (QoL) score, bone mineral density (BMD) around the prosthesis, and adverse events were compared between the two groups. The measuring range of BMD around the prosthesis was divided into seven regions of interest (ROI). The sample size was calculated to detect a mean difference in BMD of 0.15 g/cm² with a standard deviation (SD) of 0.3. The error was set at 0.05 and the power level at 90% with additional compensation for a possible dropout rate of 20%.

RESULTS

A total of 240 participants in the study up to 24 months after THA. There were no significant differences in the mean BMD of all the zones between groups before surgery (all P > 0.05). However, there were significant differences in the BMD of Gruen zones 4 and 7 between groups at 6 months postoperatively (both P < 0.05); there were significant differences in Gruen zones 1, 4, 6, and 7 at 12 months postoperatively (all P < 0.01); there were significant differences in Gruen zones 1, 2, 4, 6, and 7 at 24 months postoperatively (all P < 0.001). Patients taking raloxifene reported higher QoL scores, with better improvement in BMD in all areas except in zones 3 and 5 compared with the control group. There were no significant differences in WOMAC pain (P = 0.4045), WOMAC function (P = 0.4456) and women's QoL scores (P = 0.5983) between groups before surgery. However, WOMAC pain, WOMAC function and women's QoL score in the treatment group were significantly better at all time points (all P < 0.05). Patients in the treatment group showed no increased adverse events, including cardiac events, stroke, venous thromboembolism, and gynecological cancer (all P > 0.05), but did show decreased odds of breast cancer in comparison with those using a placebo (P = 0.0437).

CONCLUSION

Raloxifene can help inhibit bone loss around the prosthesis and improve the QoL of postmenopausal women after THA with no increased adverse events, and can even decrease the odds of breast cancer.

Clinical Impact of the Fracture Risk Assessment Tool on the Treatment Decision for Osteoporosis in Patients with Knee Osteoarthritis: A Multicenter Comparative Study of the Fracture Risk Assessment Tool and World Health Organization Criteria

Background: To compare the frequency of high-risk osteoporotic fracture in patients with knee OA (OA) using the fracture risk assessment tool (FRAX) and the bone mineral density (BMD). Methods: We retrospectively assessed 282 Korean patients with knee OA who visited five medical centers and 1165 healthy controls (HCs) aged ≥50 years without knee OA. After matching for age, sex, and body mass index, 478 subjects (239 patients with knee OA and 239 HCs) were included. Results: Based on the BMD, the frequency of osteoporosis was 40.2% in patients with knee OA and 36.4% in HCs. The predicted mean FRAX major osteoporotic fracture probabilities calculated with or without femur neck BMD differed significantly between the knee OA and HCs (6.9 ± 3.8% versus 6.1 ± 2.8%, p = 0.000 and 8 ± 3.6% versus 6.8 ± 2.3%, p < 0.001, respectively). The mean FRAX hip fracture probabilities calculated with or without femur neck BMD differed significantly in the knee OA and HCs (2.1 ± 2.4% versus 1.7 ± 1.8%, p = 0.006 and 3 ± 2.3% versus 2.4 ± 1.6%, p < 0.001, respectively). Conclusion: Our study suggests that FRAX may have a clinical impact on treatment decisions to reduce osteoporotic facture in patients with knee OA.

Ficus deltoidea Prevented Bone Loss in Preclinical Osteoporosis/Osteoarthritis Model by Suppressing Inflammation

Osteoporosis (OP) and osteoarthritis (OA) are debilitating musculoskeletal diseases of the elderly. Ficus deltoidea (FD) or mistletoe fig, a medicinal plant, was pre-clinically evaluated against OP- and OA-related bone alterations, in postmenopausal OA rat model. Thirty twelfth-week-old female rats were divided into groups (n = 6). Four groups were bilateral ovariectomized (OVX) and OA-induced by intra-articular monosodium iodoacetate (MIA) injection into the right knee joints. The Sham control and OVX-OA non-treated groups were given deionized water. The three other OVX-OA groups were orally administered daily with FD extract (200, 400 mg/kg) or diclofenac (5 mg/kg) for 4 weeks. The rats' bones and blood were evaluated for protein and mRNA expressions of osteoporosis and inflammatory indicators, and micro-CT computed tomography for bone microstructure. The non-treated OVX-OA rats developed severe OP bone loss and bone microstructural damage in the subchondral and metaphyseal regions, supported by reduced serum bone formation markers (osteocalcin, osteoprotegerin) and increased bone resorption markers (RANKL and CTX-I). The FD extract significantly (p < 0.05) mitigated these bone microstructural and biomarker changes by dose-dependently down-regulating pro-inflammatory NF-κβ, TNF-α, and IL-6 mRNA expressions. The FD extract demonstrated good anti-osteoporotic properties in this OP/OA preclinical model by stimulating bone formation and suppressing bone resorption via anti-inflammatory pathways. This is among the few reports relating the subchondral bone plate and trabecular thickening with the metaphyseal trabecular osteopenic bone loss under osteoporotic-osteoarthritis conditions, providing some insights on the debated inverse relationship between osteoporosis and osteoarthritis.

Ultrastructural change of the subchondral bone increases the severity of cartilage damage in osteoporotic osteoarthritis of the knee in rabbits

Osteoporotic osteoarthritis is a phenotype of osteoarthritis (OA) manifested as fragile and osteoporotic subchondral bone. However, the ultrastructural features of subchondral bone in osteoporosis OA have not been determined. The study was aimed to investigate the ultrastructural dynamic changes of subchondral bone in osteoporotic OA model and how the ultrastructural damage in the subchondral bone caused by osteoporosis deteriorated the cartilage damage in OA. Eighteen rabbits were equally randomized to three groups, including the control, the OA and the osteoporotic OA groups. The structural changes of cartilage were evaluated by HE and safranin-O fast green staining, the Mankin's grading system was used to assess the stage of OA progression. And microstructural or ultrastructural changes in subchondral bone were assessed by micro-computed tomography or by scanning electron microscopy. According to the changes of cartilage histopathology, the OA group was in the early pathological stage of OA while the osteoporotic OA group was in the middle stage of OA based on Mankin's grading system. In addition, the damage of cartilage surface, reduction in the number of chondrocytes and the matrix staining were more increased in the osteoporotic OA group compared to the OA group. Compared to the OA group, the subchondral bone in the microstructure and ultrastructure in the osteoporotic OA group showed more microfracture changes in trabecular bone with more destructions of the tree-like mesh. Moreover, the collagen fibers were random rough with a fewer amount of bone lacunae in subchondral cortical plate in the osteoporotic OA group compared to the OA group. These findings indicated that the subchondral bone ultrastructure in the osteoporotic OA model was characterized by the destruction of the network structure and collagen fibers. The subchondral bone ultrastructural damage caused by osteoporosis may change mechanical properties of the upper cartilage and aggravate OA cartilage. Therefore, early diagnosis and treatment of osteoporosis is of great significance to prevent early OA from further developing osteoporotic OA.

Bone Mineral Density is Lower in Patients with Severe Knee Osteoarthritis and Attrition

Bone quality is probably important for the survival of knee arthroplasty (KA), but little is known about systemic bone mineral density and bone turnover in patients prior to KA surgery. The aim of this study was to explore the prevalence of osteoporosis and bone turnover in relation to knee osteoarthritis (OA) grade in patients scheduled for KA surgery. Prospective preoperative evaluation of 450 patients (259 females) prior to KA between 2014 and 2016 with standing knee radiography, Dual-energy X-ray absorptiometry (DXA), biomarkers for bone turnover (CTX, P1NP), and vitamin D. Grading of knee OA was done with the Altman Atlas and Kellgren Lawrence (KL). Adjustments for age and BMI were made. The mean age was 67.9 years (range 39-94), and mean BMI was 28.8 (SD 4.8). The prevalence of osteoporosis was 9.6% (CI 95% 7.2; 12.7), while the proportion of patients with osteopenia was 36.0%. T score was similar between KL OA grade 3 and 4 (p = 0.06); however, T score was lower (p = 0.02) with the worst knee OA grade (attrition). The median serum Vitamin D level was 78.5 nmol/L (range 10-196), and there was no association between serum vitamin D and the grade of OA (p > 0.88). P1NP was significantly higher in KL grade 4 compared to KL grade 3 (p = 0.03), but there was no association between KL grade and CTX (p = 0.21). 10% had osteoporosis, which is similar to the age-matched background population. Bone mineral density was lower with severe knee osteoarthritis (attrition), and P1NP was higher with worse osteoarthritis grading.

Risk factors for unsuccessful acetabular press-fit fixation at primary total hip arthroplasty

BACKGROUND

Surgeon at primary total hip arthroplasty sometimes cannot achieve sufficient cementless acetabular press-fit fixation and must resort to other fixation methods. Despite a predominant use of cementless cups, this issue is not fully clarified, therefore we performed a large retrospective study to: (1) identify risk factors related to patient or implant or surgeon for unsuccessful intraoperative press-fit; (2) check for correlation between surgeons' volume of operated cases and the press-fit success rate.

HYPOTHESIS

Unsuccessful intra-operative press-fit more often occurs in older female patients, particular implants, due to learning curve and low-volume surgeons.

MATERIALS AND METHODS

Retrospective observational cohort of prospectively collected intraoperative data (2009-2016) included all primary total hip arthroplasty patients with implant brands that offered acetabular press-fit fixation only. Press-fit was considered successful if acetabulum was of the same implant brand as the femoral component without additional screws or cement. Logistic regression models for unsuccessful acetabular press-fit included patients' gender/age/operated side, implant, surgeon, approach (posterior n=1206, direct-lateral n=871) and surgery date (i.e. learning curve).

RESULTS

In 2077 patients (mean 65.5 years, 1093 females, 1163 right hips), three different implant brands (973 ABG-II™-Stryker, 646 EcoFit™ Implantcast, 458 Procotyl™ L-Wright) were implanted by eight surgeons. Their unsuccessful press-fit fixation rates ranged from 3.5% to 23.7%. Older age (odds ratio 1.01 [95% CI: 0.99-1.02]), female gender (2.87 [95% CI: 2.11-3.91]), right side (1.44 [95% CI: 1.08-1.92]), surgery date (0.90 [95% CI: 1.08-1.92]) and particular implants were significant risk factors only in three surgeons with less successful surgical technique (higher rates of unsuccessful press-fit with Procotyl™-L and EcoFit™ [P=0.01]). Direct-lateral hip approach had a lower rate of unsuccessful press-fit than posterior hip approach (P<0.01), but there was no correlation between surgeons' volume and rate of successful press-fit (Spearman's rho=0.10, P=0.82). Subcohort of 961 patients with 5-7-years follow-up indicated higher early/late cup revision rates with unsuccessful press-fit.

DISCUSSION

Success of press-fit fixation depends entirely on the surgeon and surgical approach. With proper operative technique, the unsuccessful press-fit fixation rate should be below 5% and the impact of patients' characteristics or implants on press-fit fixation is then insignificant. Findings of huge variability in operative technique between surgeons of the presented study emphasize the need for surgeon-specific data stratification in arthroplasty studies and indicate the possibility of false attribution of clinically observed phenomena to patient-related factors in pooled data of large centers or hip arthroplasty registers.

LEVEL OF EVIDENCE

Level III, retrospective observational case control study.

Cementless Total Hip Arthroplasty in Octogenarians

BACKGROUND

Although several studies indicate excellent results for cementless implants, controversy persists regarding its use in elderly patients. We determined to evaluate the outcome on patients aged over 80 years who were treated with cementless total hip arthroplasty for primary osteoarthritis of the hip.

METHODS

We assessed the data of 162 consecutive total hip arthroplasties in octogenarian patients (mean age 83 years, range 80-96 years). A control group was created, consisting of 342 patients aged younger than 80 years (mean age 65 years, range 37-79 years). The median follow-up of the cohort was 128.4 months (range 6-211).

RESULTS

Competing risk analyses revealed a cumulative implant survival of 98.1% at 5 and 10 years in the study group compared to 99.1% and 98.4% in the control group, taking system exchange as the end point. No differences in regard to system exchange could be detected between the groups. A significantly worsened complication-free survival rate was evident in the octogenarian group. Osteoporosis was the most powerful risk factor that proved to have a significant negative impact on development of complications.

CONCLUSION

Uncemented total hip arthroplasty is a viable option for the elderly patient. In this population sector, an excellent rate of implant survival can be expected. However, a significant increase of total complications in the octogenarian group could be detected, and was mainly caused by an elevated number of early postoperative complications. Osteoporosis turned out to be a strong risk factor in regard to complication-free survival. Surgeons should therefore be aware of this.

Osteoporosis in brazilian patients awaiting knee arthroplasty

OBJECTIVE

The primary objective of this study was to determine the prevalence of osteoporosis and osteopenia prior to total knee arthroplasty (TKA) in female patients. As a secondary objective, we evaluated the incidence of hip fractures, types of drugs to treat osteoporosis and serum vitamin D levels.

METHOD

This is a transversal, descriptive and observational study which evaluated 60 women above age 55 prior to total knee replacement.

RESULTS

Mean patient age was 71.4 years. Osteoporosis was present in 16.7% of the sample and osteopenia in 15%. In the patients with osteoporosis, femur fracture (20%) was most frequent. Most of the group with osteopenia did not take any medication to treat this condition (55.6%), while most patients with osteoporosis took alendronate (30%) and 30% did not take any medication.

CONCLUSION

The female population awaiting total knee replacement should be considered at risk for osteoporosis, confirming recent findings in the literature. Level of Evidence III, Control Case Study.

Osteoporosis and osteoarthritis: shared mechanisms and epidemiology

PURPOSE OF REVIEW

Osteoporosis and osteoarthritis are different diseases, with differences in risk factors, bone mineral density (BMD), BMI, phenotype, morbidity and mortality. We review new data on the role of bone metabolism in osteoporosis and osteoarthritis.

RECENT FINDINGS

The insights in the common convergent and divergent risk factors between osteoarthritis and osteoporosis have resulted in new findings on the role of BMD, BMI, falls, genetics and epigenetics in the pathophysiology of both diseases and on the increased fracture risk in osteoporosis and osteoarthritis. The relation between BMD, BMI and fracture risk in osteoarthritis is dependent on the stage, definition and location of the osteoarthritis and method of BMD measurement. It has been suggested that osteoarthritis should be further specified in terms of bone involvement.

SUMMARY

These new findings open the way to better understand the bone subtypes of osteoarthritis (osteoporotic, bone forming and erosive) and the common and different ways bone is involved in osteoporosis and osteoarthritis. Much can be expected from further prospective studies, when taking into account the heterogeneous nature of both osteoporosis and osteoarthritis.