The association of parity with osteoarthritis and knee replacement in the multicenter osteoarthritis study

Sex differences in osteoarthritis prevalence, pain perception, physical function and therapeutics

OBJECTIVE

Women have a higher prevalence of osteoarthritis (OA) and worse clinical courses than men. However, the underlying factors and therapeutic outcomes of these sex-specific differences are incompletely researched. This review examines the current state of knowledge regarding sex differences in OA prevalence, risk factors, pain severity, functional outcomes, and use and response to therapeutics.

METHODS

PubMed database was used with the title keyword combinations "{gender OR sex} AND osteoarthritis" plus additional manual search of the included papers for pertinent references, yielding 212 references. Additional references were added and 343 were reviewed for appropriateness.

RESULTS

Globally, women account for 60% of people with osteoarthritis, with a greater difference after age 40. The higher risk for women may be due to differences in joint anatomy, alignment, muscle strength, hormonal influences, obesity, and/or genetics. At the same radiographic severity, women have greater pain severity than men, which may be explained by biologically distinct pain pathways, differential activation of central pain pathways, differences in pain sensitivity, perception, reporting, and coping strategies. Women have greater limitations of physical function and performance than men independent of BMI, OA severity, injury history, and amount of weekly exercise. Women also have greater use of analgesic medications than men but less use of arthroplasty and poorer prognosis after surgical interventions.

CONCLUSIONS

The recognition of sex differences in OA manifestations and management could guide tailoring of sex-specific treatment protocols, and analysis of sex as a biological variable in future research would enhance development of precision medicine.

Causal association of menstrual reproductive factors on the risk of osteoarthritis: A univariate and multivariate Mendelian randomization study

OBJECTIVE

Several observational studies have revealed a potential relationship between menstrual reproductive factors (MRF) and osteoarthritis (OA). However, the precise causal relationship remains elusive. This study performed Mendelian randomization (MR) to provide deeper insights into this relationship.

METHODS

Utilizing summary statistics of genome-wide association studies (GWAS), we conducted univariate MR to estimate 2 menstrual factors (Age at menarche, AAM; Age at menopause, AMP) and 5 reproductive factors (Age at first live birth, AFB; Age at last live birth, ALB; Number of live births, NLB; Age first had sexual intercourse, AFSI; Age started oral contraceptive pill, ASOC) on OA (overall OA, OOA; knee OA, KOA and hip OA, HOA). The sample size of MRF ranged from 123846 to 406457, and the OA sample size range from 393873 to 484598. Inverse variance weighted (IVW) method was used as the primary MR analysis methods, and MR Egger, weighted median was performed as supplements. Sensitivity analysis was employed to test for heterogeneity and horizontal pleiotropy. Finally, multivariable MR was utilized to adjust for the influence of BMI on OA.

RESULTS

After conducting multiple tests (P<0.0023) and adjusting for BMI, MR analysis indicated that a lower AFB will increase the risk of OOA (odds ratio [OR] = 0.97, 95% confidence interval [CI]: 0.95-0.99, P = 3.39×10-4) and KOA (OR = 0.60, 95% CI: 0.47-0.78, P = 1.07×10-4). ALB (OR = 0.61, 95% CI: 0.45-0.84, P = 2.06×10-3) and Age AFSI (OR = 0.66, 95% CI: 0.53-0.82, P = 2.42×10-4) were negatively associated with KOA. In addition, our results showed that earlier AMP adversely affected HOA (OR = 1.12, 95% CI: 1.01-1.23, P = 0.033), and earlier ASOC promote the development of OOA (OR = 0.97, 95% CI: 0.95-1.00, P = 0.032) and KOA (OR = 0.58, 95% CI: 0.40-0.84, P = 4.49×10-3). ALB (OR = 0.98, 95% CI: 0.96-1.00, P = 0.030) and AFSI (OR = 0.98, 95% CI: 0.97-0.99, P = 2.66×10-3) also showed a negative association with OOA but they all did not pass multiple tests. The effects of AAM and NLB on OA were insignificant after BMI correction.

CONCLUSION

This research Certificates that Early AFB promotes the development of OOA, meanwhile early AFB, ALB, and AFSI are also risk factors of KOA. Reproductive factors, especially those related to birth, may have the greatest impact on KOA. It provides guidance for promoting women's appropriate age fertility and strengthening perinatal care.

Reproductive history is associated with functional disabilities and symptoms in women with knee osteoarthritis: a case-control study

OBJECTIVES

Studies that have examined the correlation between reproductive history and knee osteoarthritis (KOA) have had heterogeneous findings. We aimed to investigate the reproductive history and its relationship with pain and physical dysfunction in women with KOA. This case-control study, comprising 204 women aged 50 and older with and without KOA recruited through random cluster sampling, was executed from February 2018 to October 2018 in the health centers of Tabriz City. The reproductive history questionnaire was completed for the subjects in two groups. Pain intensity and functional dysfunction caused by KOA were evaluated using the Visual analogue scale and the Western Ontario and McMaster index, respectively.

RESULTS

The women's age of menarche in the case group was significantly lower (p = 0.031), and the number of pregnancies (p = 0.017) and the average duration of breastfeeding (p = 0.039) were substantially higher than those of the control group. Older age at the first menstruation (OR = 0.851) was a protective factor, and higher parity (OR = 8.726) was a risk factor for KOA. In the women with KOA, the younger age of the mother at the birth of the first alive baby and the longer duration of breastfeeding were associated with higher pain intensity and functional disorders.

Hysterectomy and risk of osteoarthritis in women: a nationwide nested case-control study

OBJECTIVE

Hysterectomy is the most common gynaecological surgery, performed mainly for benign uterine pathologies in women. Studies have suggested that hysterectomy is associated with osteoarthritis (OA); however, the association remains controversial. This study aimed to investigate the association between hysterectomy and the risk of OA.

METHOD

We performed a population-based nested case-control study using the National Health Insurance programme database from 2000 to 2016 in Taiwan. All medical conditions for each case and control were categorized using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and ICD-10. A multiple conditional logistic regression model was applied to analyse the adjusted odds ratio (aOR) and 95% confidence interval (CI) for the association between hysterectomy and OA.

RESULTS

Our analyses included 16 592 patients with OA and 66 368 matched controls. After adjustment for possible confounders, hysterectomy had a significant association with OA (aOR = 1.19, 95% CI = 1.09-1.30), especially knee OA (aOR = 1.25, 95% CI = 1.13-1.38). Furthermore, women who received oestrogen therapy (ET) alone and patients who underwent hysterectomy without ET showed a greater risk of OA development compared to women who did not receive ET (aOR = 1.14, 95% CI = 1.07-1.23, and aOR = 1.19, 95% CI = 1.08-1.31, respectively).

CONCLUSION

Our findings indicate that hysterectomy is associated with OA, especially knee OA. We also found that women who received ET alone and patients who underwent hysterectomy without ET had an increased risk of OA.

Association of hormone replacement therapy and the risk of knee osteoarthritis: A meta-analysis

BACKGROUND

The relationship between hormone replacement therapy (HRT) and osteoarthritis is controversial in epidemiological studies. With the aim of better understanding the effect of HRT use, this first meta-analysis was implemented to explore the association of HRT and knee OA.

METHODS

A series of data is retrieved from Web of Science, PubMed, and Embase databases to observe the association of HRT and knee osteoarthritis up to December 2021. Two separated reviewers chose the research, extracted the data, and evaluated the study quality. Pooled estimates of 95% CI and HRs were acquired through a random-effects model.

RESULTS

Finally, there existed 13 pieces of research, containing one case-control research, four cross-sectional pieces of research, as well as eight cohort pieces of research, involving 2573,164 participants. The overall results showed that the use of HRT was related to a raised risk of knee OA (HR = 1.24, 95% CI 1.07-1.45). And the pooled analysis showed a statistically significant raised risk of knee joint replacement (HR = 1.30, 95% CI 1.09-1.54) when using HRT. In addition, the outcome exhibits the raised knee OA risk for the present users of HRT (HR = 1.40, 95% CI 1.16-1.68) according to HRT status. In the past users of HRT, the augment of knee OA risk was not statistically evident (HR = 1.16, 95% CI 0.94-1.42).

CONCLUSION

We observed that HRT use was related to a raised knee OA risk. Furthermore, future studies might focus on relevant mechanistic to verify our observed associations.

Female reproductive factors and risk of joint replacement arthroplasty of the knee and hip due to osteoarthritis in postmenopausal women: a nationwide cohort study of 1.13 million women

OBJECTIVES

Previous studies of the relationships between female reproductive factors and osteoarthritis (OA) have shown conflicting results. In this study, we aimed to explore the relationships between reproductive factors and joint replacement arthroplasty of the knee (TKRA) and hip (THRA) in a large nationwide population-based cohort of postmenopausal Korean women.

METHODS

We included 1,134,680 subjects who participated in national health examinations in 2009 in the study. The study outcomes were incident THRA or TKRA due to severe hip or knee OA. The relationships between reproductive factors and THRA or TKRA were evaluated using a multivariable-adjusted proportional hazards model.

RESULTS

During a mean follow-up duration of 8.2 years, 1,610 incident THRA cases and 60,670 incident TKRA cases were observed. Later age at menarche, longer breastfeeding, HRT and OC use were associated with increased risk of TKRA for severe knee OA, while later age at menopause and longer reproductive span were associated with decreased risk. With regard to THRA for severe hip OA, later menarche, longer breastfeeding, HRT more than 5 years, and OC use more than 1 year were associated with higher risk. The associations between reproductive factors and severe OA were more pronounced in underweight and younger subjects.

CONCLUSION

We found that shorter estrogen exposure was associated with higher risk of TKRA due to severe knee OA, and such associations were more pronounced in underweight and younger subjects. The association between shorter estrogen exposure and THRA was not robust.

Risk Factors of Body Mass Index (BMI), Age of Menarche, Parity and Hormonal Contraception of Genu Osteoarthritis in Female Patients

Osteoarthritis (OA) is a degenerative disease related to joint cartilage and commonly occurs in the knee joint. The 2013 National Survey recorded the prevalence of joint diseases in East Java was 26.9%. OA affected more women than men due to the estrogen and caused disabilities in many women. This study aimed to find the relationship between Body Mass Index (BMI), age of menarche, parity, and the use of hormonal contraceptives against OA in genu at Universitas Airlangga Hospital, Surabaya. This was an analytic observational study with a case-control approach. Data collection was carried out through a short interview using a questionnaire. The sample size was calculated using a formula and found that the study required 42 patients with OA in the case group and 42 patients without OA in the control group. The case group was dominated by patients with 56-60 years old age (62.1%), BMI 23-24.9 kg/m2 (58.7%), menarche age 12-13 years (53.6%), multiparous (52.6%), having contraception pill usage history (62.3%) particularly using combination pills (60.5%) with a mean duration of use > 1 year (56.8%). There was a relationship between BMI and type of hormonal contraceptive used against genu OA in female patients at Universitas Airlangga Hospital Surabaya.

Association of vitamin D, BMD and knee osteoarthritis in postmenopausal women

OBJECTIVES

The aim of this study was to analyze the association of knee OA with bone mineral density (BMD) and vitamin D serum levels in postmenopausal women.

METHODS

A cross-sectional study including 240 postmenopausal women with knee OA was conducted. Demographic data were recorded along with balance and functionality scores. Knee OA severity was assessed by the radiological Kellgren & Lawrence scale. BMD and T-scores were calculated in hips and lumbar spine. Serum levels of vitamin D were also measured.

RESULTS

High BMI (p<0.005), high number of children (p=0.022) and family history of hip fracture (p=0.011) are significantly associated with knee OA severity. Lumbar spine OP is negatively associated with knee OA (p<0.005). A significant difference was detected between vitamin D deficiency and severe knee OA, adjusted for BMD [OR (95%CI); 3.1 (1.6-6.1), p=0.001]. BMD does not affect the relationship of vitamin D levels in relation to OA and vitamin D levels do not affect the relationship of BMD with OA.

CONCLUSIONS

Low BMD has a protective role against knee OA while vitamin D deficiency contributes significantly to knee OA severity. However, the association between OA and OP is not affected by vitamin D deficiency and the association of OA and vitamin D serum levels is not affected by BMD.

Abortion is associated with knee osteoarthritis among older women in China: A STROBE-compliant article

The current studies revealed inconsistent relationship between reproductive factors and osteoarthritis. Community-based research has not been conducted in China. The study was to examine the association of reproductive factors with the prevalence of knee osteoarthritis (OA).Through a multistage stratified random sampling method, 10 streets or villages from 5 cities in Hunan province were randomly selected, a total 2746 eligible women aged 50 to 83 were recruited in this cross-sectional study. A structured questionnaire including demographic factors, socio-economic status, reproductive factors, and knee OA was used. According to the criteria of American College of Rheumatology, clinical knee OA was assessed by doctors in community or village health clinics for knee pain, age, morning stiffness, crepitus on active motion or for knee pain, morning stiffness, crepitus on active motion, and tenderness of the bony navigation of the joint. Self-reported age of menarche, parity, abortion history, and menopausal status were collected.The prevalence of knee OA was 13.44%. Abortion is associated with knee OA (odds ratio [OR] = 1.271, 95% confidence interval [CI] = 1.007, 1.606), but age at menarche, parity, and menopausal status were not the factors. Furthermore, age (OR = 1.040, 95% CI = 1.020, 1.060), weight (OR = 1.019, 95% CI = 1.004, 1.035), higher education level (OR = 1.530, 95% CI = 1.121, 2.088), higher monthly household income (OR = .583, 95% CI = 0.441, 0.770 for 3000-4999 ¥ and OR = 0.599, 95% CI = 0.431, 0.833 for 5000 ¥ or more), and chronic gastritis (OR = 3.364, 95% CI = 2.548, 4.442) were associated with knee OA.Abortion may increase the risk of knee OA. Special attention should be paid to women with a history of abortion, and women who are planning to abort should be informed of the risk of knee OA later in life. The relationship between abortion and knee OA should be interpreted with caution and further confirmed.

Reproductive history and osteoarthritis in the Women's Health Initiative

Objective: To investigate the relationship between self-reported osteoarthritis (OA) and reproductive factors in the Women's Health Initiative (WHI). Method: We used multivariable logistic regression to study the association of self-reported OA and reproductive factors in the WHI Observational Study and Clinical Trial cohorts of 145 965 postmenopausal women, in a retrospective cross-sectional format. Results: In our cohort, we observed no clinically significant associations between reproductive factors and OA given small effect sizes. The following factors were associated with statistically significant increased likelihood of developing OA: younger age at menarche (p < 0.001), history of hysterectomy [adjusted odds ratio (aOR) 1.013, 95% confidence interval (CI) 1.004-1.022, p = 0.04 vs no hysterectomy], history of unilateral oophorectomy (aOR 1.015, 95% CI 1.004-1.026, p < 0.01 vs no oophorectomy), parity (aOR 1.017, 95% CI 1.009-1.026, p < 0.001), ever use of oral contraceptives (aOR 1.008, 95% CI 1.001-1.016, p < 0.01 vs never use), and current use of hormonal therapy (reference current users, aOR 0.951, 95% CI 0.943-0.959 for never users; aOR 0.981, 95% CI 0.972-0.989 for past users; global p < 0.001). Age at menopause, first birth, and pregnancy were not associated with OA. Among parous women, no clear pattern was observed with number of pregnancies, births, or duration of breastfeeding in relation to OA. Conclusion: Our study showed that reproductive factors did not have significant clinical associations with OA after controlling for confounders. This may be due to complex hormonal effects. Additional investigation is warranted in prospective cohort studies. The Women's Health Initiative is registered under ClinicalTrials.gov. Trial registration ID: NCT00000611.

Development and validation of a prediction model for incident hand osteoarthritis in the HUNT study

OBJECTIVE

To develop and externally validate prediction models for incident hand osteoarthritis (OA) in a large population-based cohort of middle aged and older men and women.

DESIGN

We included 17,153 men and 18,682 women from a population-based cohort, aged 35-70 years at baseline (1995-1997). Incident hand OA were obtained from diagnostic codes in the Norwegian National Patient Register (1995-2018). We studied whether a range of self-reported and clinically measured predictors could predict hand OA, using the Area Under the receiver-operating Curve (AUC) from logistic regression. External validation of an existing prediction model for male hand OA was tested on discrimination in a sample of men. Bootstrapping was used to avoid overfitting.

RESULTS

The model for men showed modest discriminatory ability (AUC = 0.67, 95% CI 0.62-0.71). Adding a genetic risk score did not improve prediction. Similar discrimination was observed in the model for women (AUC = 0.62, 95% CI 0.59-0.64). Prediction was not improved by adding a genetic risk score or hormonal and reproductive factors. Applying external validation, similar results were observed among men in HUNT (The Nord-Trøndelag Health Study) as in the developmental sample (AUC = 0.62, 95% CI 0.57-0.65).

CONCLUSION

We developed prediction models for incident hand OA in men and women. For women, the model included body mass index (BMI), heavy physical work, high physical activity and perceived poor health. The model showed moderate discrimination. For men, we have shown that a prediction model including BMI, education and information on sleep can predict incident hand OA in several populations with moderate discriminative ability.

The Association of Parity with Greater Dynamic Pronation of the Feet

BACKGROUND

Postpartum women are at increased risk for lower limb musculoskeletal disorders. Foot arch collapse following pregnancy has been reported as a mechanism for this increased risk. However, dynamic changes during gait in postpartum women have not been reported. Therefore, we assessed the association between parity and dynamic foot pronation during gait.

OBJECTIVE

To determine (1) if there is an association between parity and dynamic foot pronation (center of pressure excursion index, CPEI) during gait; and (2) the extent to which there is a dose-effect of parity on foot pronation.

DESIGN

The Multicenter Osteoarthritis Study (MOST) Study is a longitudinal cohort study of adults with or at risk for knee osteoarthritis (OA).

SETTING

Two communities in the United States, Birmingham, Alabama and Iowa City, Iowa.

INTERVENTIONS

Not applicable PARTICIPANTS: A population-based sample of 1177 MOST participants who were female, had complete CPEI and parity data and completed the baseline, 30- and 60-month visits.

MAIN OUTCOME MEASURES

Odds of a one quintile decrease in CPEI by parity group and mean CPEI by parity group.

RESULTS

In 1177 women, mean age was 67.7 years and mean body mass index (BMI) was 30.6 kg/m² . As parity increased, there was significantly greater foot pronation, lower mean CPEI: 19.1 (18.2-20.1), 18.9 (18.4-19.4), 18 (17.5-18.6) to 17.5 (16.4-18.6) in the 0 to 4 and >5 children groups, respectively; (P = .002), which remained significant after adjusting for race and clinic site (P = .005). There was a positive linear trend (β = 1.08, 1.03-1.14) in odds ratios of a one quintile decrease in CPEI (greater pronation) with increasing parity level (P = .004), which remained significant after adjusting for race and clinic site (P = .01). After adjusting for age and BMI, these two associations were no longer statistically significant.

CONCLUSIONS

This study indicates a positive correlation between parity and greater dynamic pronation of the feet.

Selective inhibition of progesterone receptor in osteochondral progenitor cells, but not in mature chondrocytes, modulated subchondral bone structures

OBJECTIVE

The presence or relative proportion of progesterone nuclear receptors (PR) in different tissues may contribute to sexual dimorphism in these tissues. PR is expressed in chondrocytes, but its function is mostly unknown. We hypothesized that the PR may regulate chondrocyte metabolism and affect subchondral bone structure.

METHODS

We utilized genetic fate mapping and immunohistochemistry to elucidate PR expression in and effect on cartilage. To define sex-dependent and chondrocyte-specific effects of the PR on subchondral bone, we selectively deleted PR in osteochondrogenic progenitor cells marked by Prx1 (Prx1; PRcKO) and Collagen 2 (Col2; PRcKO), or in matured chondrocytes marked by aggrecan (Acan; PRcKO) and evaluated subchondral bone structure at 4 months of age. Chondrocyte aging was monitored by anti-senescence marker p16INK4a, and MMP13, one of the Senescence-Associated Secretary Phenotype (SASP) components.

RESULTS

Compared to wild-type (WT) mice, the female Prx1; PRcKO and the Col2; PRcKO mice had greater total subchondral bone volume and greater subchondral cortical bone thickness, with increased estimated subchondral bone stiffness and failure load in both female and male Col2; PRcKO mice. Moreover, Col2; PRcKO mice from both sexes had greater bone formation and bone strength at the femurs. In contrast, we did not observe any subchondral bone changes in Acan; PRcKO mice other than higher work-to-failure observed in the male Acan; PRcKO mice. Despite no detected difference in articular cartilage between the WT and the PR; chondrocyte conditional deletion mice, there were greater numbers of senescent chondrocytes and increased MMP13 expression, especially in the male mutant mice.

CONCLUSION

These findings suggest that selective inhibition of PR in osteoprogenitor cells, but not in terminally differentiated chondrocytes, induced an increased subchondral bone phenotype and high estimated subchondral bone strength, which might be associated with the development of osteoarthritis in older age.

Reproductive factors and risk of total knee replacement due to severe knee osteoarthritis in women, the Singapore Chinese Health Study

OBJECTIVES

Knee osteoarthritis (OA) is more common in women, and may be related to reproductive or hormonal factors. We evaluated these factors with the risk of total knee replacement (TKR) for severe knee OA among women.

METHODS

The Singapore Chinese Health Study recruited 63,257 Chinese aged 45-74 years from 1993 to 1998, and among them, 35,298 were women. Information on height, weight, lifestyle factors, number of biological children, ages at menarche and menopause, and use of hormonal therapies was collected through interviews. Incident cases of TKR were identified via linkage with nationwide database.

RESULTS

There were 1,645 women with TKR after mean follow-up of 14.8 years. Higher parity was associated with increased TKR risk in a stepwise manner (P for trend <0.001). Compared to nulliparous women, those with ≥5 children had the highest risk [hazard ratio (HR) 2.01, 95% confidence intervals (CIs) 1.50-2.70]. The effect of parity on TKR risk was significantly stronger among lean women compared to heavier women; HRs (95% CIs) for highest parity was 4.86 (2.22-10.63) for women with body mass index (BMI) <23 kg/m² and 1.57 (1.14-2.14) for those ≥23 kg/m² (P for interaction = 0.001). Earlier age at menarche and use of oral contraceptives were significantly associated with TKR in a stepwise manner (P for trend ≤0.002). Age at menopause and use of hormonal therapy were not associated with TKR risk.

CONCLUSION

Higher parity, earlier age of menarche and use of oral contraceptives were associated with increased risk of TKR for severe knee OA among women.

A cross-sectional study to screen community health volunteers for hip/knee-osteoarthritis and osteoporosis

CONTEXT

Osteoarthritis (OA) is a degenerative disease mainly affecting hip and knee joints, and osteoporosis is characterized by diminution of bone mass. Both these diseases have a substantial economic impact on society. Community health volunteers (CHVs) being peripheral health workers are prone to such diseases owing to their sociodemographic and occupational profile.

AIM

This study was conducted to estimate the proportion of hip/knee OA and osteoporosis among CHVs and understand determinants of their current bone health status.

MATERIALS AND METHODS

Screening for OA was done using a tool adopted from a previous study after obtaining due permissions. Weight, height, blood pressure, and bone mineral density of all participants were recorded. Statistical tests such as Chi-square and multiple logistic regression were used for analysis of data.

RESULTS

Out of 80 participants, 50 (62.5%) had increased body mass index (overweight + obese), 10 (12.5%) were hypertensive, 14 (17.5%) CHVs screened positive for hip OA, and 29 (36.3%) were positive for knee OA. Hip OA was associated with advancing age, parity, and obesity. Knee OA was associated with age and exercise. In total, 16.3% subjects were found to have osteoporosis and 61.2% had osteopenia.

CONCLUSIONS

This study showed that a remarkable proportion of CHVs had bone and joint problems. CHVs must, therefore, receive preventive measures such as health education and screening for these diseases.

Pregnancy Results in Lasting Changes in Knee Joint Laxity

BACKGROUND

Altered joint laxity can contribute to joint dysfunction. Knee joint laxity has been shown to increase during pregnancy, but its long-term persistence is unknown.

OBJECTIVE

To determine whether pregnancy leads to lasting increases in knee joint compliance and laxity that persist longer than 4 months postpartum.

DESIGN

Prospective cohort study.

SETTING

A motion analysis laboratory at an academic medical center.

PARTICIPANTS

Fifty healthy women in their first trimester of pregnancy (mean ± SD 29.2 ± 4.3 years old and baseline body mass index 26.0 ± 5.4 kg/m² ) were recruited.

INTERVENTION

End-range knee laxity and midrange joint compliance were measured during the first trimester and 19 ± 4 weeks postpartum. Anterior-posterior and varus-valgus laxity were measured using 3-dimensional motion tracking while applying forces and moments in each respective plane using the Vermont Knee Laxity Device. Nonlinear models were constructed to assess relations between applied forces and joint translation, comparing early pregnancy with postpartum.

OUTCOMES

Multiplanar knee laxity and compliance.

RESULTS

Peak varus-valgus (20-22%; P = .001) and posterior translation (51%; P < .001) of the tibia relative to the femur decreased from baseline, with a concomitant decrease in laxity (P < .001) and compliance (P = .039) in the coronal plane and in the posterior direction in primiparous (P = .009) and multiparous (P = .014) women. For primiparous women, laxity (P < .001) and compliance (P = .009) increased in the anterior direction.

CONCLUSIONS

Pregnancy resulted in a lasting decrease in multiplanar knee laxity and compliance in the varus and posterior directions with an increase in anterior compliance. The effects of these changes in laxity and compliance of the passive stabilizers on knee loading patterns, articular contact stresses, and risk for osteoarthritis and other musculoskeletal disorders will require additional research.

LEVEL OF EVIDENCE

II.

Static and dynamic effects of customized insoles on attenuating arch collapse with pregnancy: A randomized controlled trial

INTRODUCTION

Anthropometric changes to the feet with pregnancy may increase risk for musculoskeletal disease. Customized arch-supportive orthoses to prevent anthropometric changes could potentially provide an inexpensive means to prevent musculoskeletal impairments and improve quality of life for women during their post-reproductive years. The objective of this prospective, randomized controlled trial was to determine whether customized foot orthoses can prevent arch collapse during pregnancy.

MATERIALS AND METHODS

Seventy-two first trimester women (age 18-40) were randomized to wear either their usual footwear (control) or their usual footwear with custom-molded arch-supportive orthoses. Each participant in the customized orthosis group had orthoses customized by a certified orthotist. Baseline assessments were completed during the first trimester and follow-up assessments were completed approximately 8 weeks postpartum. The primary outcome measurements were static arch height index (AHI), arch drop, arch rigidity index, and center of pressure excursion index (CPEI).

RESULTS

There were no statistically significant differences in the change in static foot structure or dynamic arch function between baseline and follow-up within either group. Comparing the customized orthosis and control groups, no significant differences were detected in change in AHI sitting (p=.44), AHI standing (p=.48), arch drop (p=.67), arch rigidity (p=.68) or CPEI (p=.77).

CONCLUSIONS

There was no difference in arch change when comparing women who were randomized to wear customized orthoses or self-selected footwear. The finding of no arch drop in either group may indicate that both groups supported their arches during the study period or that neither group was predisposed to lose arch height with pregnancy.

Combined effects of reproductive and hormone factors and obesity on the prevalence of knee osteoarthritis and knee pain among middle-aged or older Chinese women: a cross-sectional study

Background

Knee osteoarthritis (KOA) is one form of degenerative arthritis that results from the breakdown of cartilage and underlying bone. The prevalence of KOA is considerably higher in women than in men; however, the reason for this difference has not been thoroughly elucidated to date. The aim of the present study was to estimate the effects of reproductive and hormone factors and obesity on KOA prevalence among Chinese women.

Methods

The cross-sectional study included 7510 women with a mean age of 62.6 ± 8.6 years. Knee pain was defined as pain or aching stiffness on most days for at least 1 month during the past 12 months or persistent pain or aching stiffness within the past week. Clinical KOA was diagnosed based on both pain complaints and a Kellgren-Lawrence grade ≥ 2 X-ray radiograph of at least one knee.

Results

Oral contraceptives use (OR 1.18, 1.05–1.34), ≥3 pregnancies (1.38, 1.20–1.60), and postmenopausal hormone replacement therapy (HT) (1.59, 1.23–2.06) were positively associated with knee pain, while oral contraceptives use (1.28, 1.04–1.57), and HT (1.79, 1.21–2.65) were positively associated with clinical KOA. Obesity and oral contraceptives use showed additive and multiplicative effects on knee pain. The OR for knee pain among women with a BMI ≥24 kg/m² and oral contraceptives use was 2.00 (1.68–2.38) compared with women with a BMI &lt; 24 kg/m² and no oral contraceptives use.

Conclusions

A high number of pregnancies, oral contraceptives use, and HT are independent risk factors for KOA, and the effects of reproductive and hormone factors on KOA may be increased by obesity.

Bone shape mediates the relationship between sex and incident knee osteoarthritis

Background

Knee bone shape differs between men and women and the incidence of knee osteoarthritis (OA) is higher in women than in men. Therefore, the purpose of the present study was to determine whether the observed difference in the incidence of knee radiographic OA (ROA) between men and women is mediated by bone shape.

Methods

We randomly sampled 304 knees from the OAI with incident ROA (i.e., development of Kellgren/Lawrence grade ≥ 2 by month 48) and 304 knees without incident ROA. We characterized distal femur and proximal tibia shape on baseline radiographs using Statistical Shape Modeling. If a specific bone shape was associated with the risk of incident ROA, marginal structural models were generated to assess the mediation effect of that bone shape on the relation of sex and risk of incident knee ROA adjusting for baseline covariates.

Results

Case and control participants were similar by age, sex and race, but case knees were from higher body mass index (BMI) participants (29.4 vs. 27.0; p < 0.001). Women had 49% increased odds of incident knee ROA compared with men (adjusted odds ratio (OR) = 1.49, 95% Confidence Interval (C.I.): 1.04, 2.12). There was an inconsistent mediation effect for tibial mode 2 between sex and incident knee ROA, with an indirect effect OR of 0.96 (95% C.I.: 0.91–1.00) and a direct effect OR of 1.56 (95% C.I.: 1.08–2.27), suggesting a protective effect for this mode. Similar findings were also observed for the mediation effect of tibia mode 10 and femur mode 4. These shape modes primarily involved differences in the angular relation of the heads to the shafts of the femur and tibia.

Conclusions

Distal femur and proximal tibia bone shapes partially and inconsistently mediated the relationship between sex and incident knee OA. Women had a higher risk of incident ROA, and specific bone shapes modestly protected them from even higher risk of ROA. The clinical significance of these findings warrant further investigation.

Female Reproductive and Hormonal Factors and Incidence of Primary Total Knee Arthroplasty Due to Osteoarthritis

OBJECTIVE

To examine the associations of female reproductive and hormonal factors with incidence of total knee arthroplasty (TKA) for osteoarthritis (OA), and to determine whether the associations differ according to overweight/obesity status.

METHODS

This study included 22,289 women in the Melbourne Collaborative Cohort Study. Data on age at menarche, pregnancy, parity, years of menstruation, oral contraceptive (OC) use, menopausal status, and hormone replacement therapy (HRT) were collected in 1990-1994. Incidence of TKA during 2001-2013 was determined by linking cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. All analyses were adjusted for age, body mass index (BMI) at midlife, change in BMI (from early reproductive age to midlife), country of birth, physical activity, smoking, and education level.

RESULTS

Over the course of 12.7 years, 1,208 TKAs for OA were identified. Ever being pregnant was associated with increased risk of TKA (hazard ratio [HR] 1.32 [95% confidence interval (95% CI) 1.06-1.63]). Parity was positively associated with risk of TKA (P for trend = 0.003). OC users had increased risk of TKA compared with non-users (for OC use of <5 years, HR 1.25 [95% CI 1.08-1.45]; for OC use of ≥5 years, HR 1.17 [95% CI 1.00-1.37]). A 1-year increase in menstruation was associated with a 1% decrease in risk of TKA (HR 0.99 [95% CI 0.97-0.99]). These associations remained significant only in women of normal weight at early reproductive age. Current HRT users had increased risk of TKA compared with non-users (HR 1.37 [95% CI 1.14-1.64]); the association was significant only in non-obese women at midlife.

CONCLUSION

Reproductive and hormonal factors were associated with risk of knee OA. These associations remained significant in women of normal weight at early reproductive age and in non-obese women at midlife. Further work is needed to understand the complex effect of these factors on knee OA.

Female hormonal factors and osteoarthritis of the knee, hip and hand: a narrative review

Osteoarthritis is a leading cause of disability with no cure. The incidence of osteoarthritis is sexually dimorphic: women have a higher rate of osteoarthritis than men after the age of 50. Research has investigated the contribution of sex hormones, reproductive factors and hormone supplementation to osteoarthritis. It has been recognized that different joints are susceptible to different risk factors for osteoarthritis. We reviewed the evidence for the effect of endogenous sex hormones, reproductive factors and hormone supplementation on joint-specific osteoarthritis of the knee, hip and hand. Although the role of these hormonal factors in the pathogenesis of osteoarthritis is complex, data suggest that endogenous hormones and reproductive factors have a role in the pathogenesis of osteoarthritis, especially knee osteoarthritis, with uncertainty for the effect of exogenous hormones. From the available data, it is hard to conclude whether this is a direct effect of hormonal factors, or whether other factors related to these hormonal factors, i.e. obesity and inflammation, have a role in this association. Further studies should consider the mediation effect of body weight and inflammation, change in body weight throughout life, circulatory levels of all endogenous hormones and circulatory levels of hormones after hormone supplementation in this complex relationship.

Age of menarche is associated with knee joint replacement due to primary osteoarthritis (The HUNT Study and the Norwegian Arthroplasty Register)

OBJECTIVE

To investigate whether parity, age at menarche, menopausal status, age at menopause, use of oral contraceptives (OC) or use of hormone replacement therapy (HRT) were associated with total knee replacement (TKR) or total hip replacement (THR) due to primary osteoarthritis.

METHOD

In a prospective cohort study of 30,289 women from the second and third surveys of the Nord-Trøndelag Health Study, data were linked to the Norwegian Arthroplasty Register (NAR) in order to identify TKR or THR due to primary osteoarthritis. Cox proportional hazards models were used to estimate the hazard ratios (HRs).

RESULTS

We observed 430 TKRs and 675 THRs during a mean follow-up time of 8.3 years. Increasing age at menarche was inversely associated with the risk of TKR (P-trend < 0.001). Past users and users of systemic HRT were at higher risk of TKR compared to never users (HR 1.42 (95% confidence interval (CI) 1.06-1.90) and HR 1.40 (95% CI 1.03-1.90), respectively). No association was found between parity, age at menarche, menopausal status, age at menopause, oral contraceptive use or HRT use and THR.

CONCLUSION

We found that increasing age at menarche reduced the risk of TKR. Past users and users of systemic HRT were at higher risk of TKR compared to never users. Parity did not increase the risk of THR or TKR.

Are estrogen-related drugs new alternatives for the management of osteoarthritis?

Osteoarthritis (OA) is a chronic degenerative disease involving multiple physiopathological mechanisms. The increased prevalence of OA after menopause and the presence of estrogen receptors in joint tissues suggest that estrogen could help prevent development of OA. This review summarizes OA research with a focus on the effects of estrogen and selective estrogen receptor modulators (SERMs). Preclinical studies and clinical trials of estrogen therapy have reported inconsistent results. However, almost all studies assessing SERM treatment have obtained more consistent and favorable effects in OA with a relatively safety and tolerability profiles. At present, some SERMs including raloxifene and bazedoxifene have been approved for the treatment of osteoporosis. In summary, estrogen-related agents may exert both a direct effect on subchondral bone and direct and/or indirect effects upon the surrounding tissues, including the articular cartilage, synovium, and muscle, to name a few. Estrogen and SERMs may be particularly favorable for postmenopausal patients with early-stage OA or osteoporotic OA, a phenotype defined by reduced bone mineral density related to high remodeling in subchondral bone. At present, no single drug exists that can prevent OA progression. Although estrogen-related drugs provide insight into the continued work in the field of OA drug administration, further research is required before SERMs can become therapeutic alternatives for OA treatment.

Population-wide incidence estimates for soft tissue knee injuries presenting to healthcare in southern Sweden: data from the Skåne Healthcare Register

Introduction

Soft tissue knee injury is a well-established and potent risk factor for development of knee osteoarthritis. However, there is a paucity of epidemiological data from the general population. Our aim was to estimate the annual person-level incidence for a wide spectrum of clinically diagnosed soft tissue knee injuries, and their distribution by age, sex, and season.

Methods

In Sweden, in- and outpatient health care is registered using each individuals’ unique personal identifier including International Classification of Diseases (ICD) 10 diagnostic code(s) as determined by physicians’ clinical examination. For the calendar years 2004–2012, we studied the population in southern Sweden, Skåne region (approx. 1.3 million). We identified residents who had at least one visit to a physician with clinically diagnosed knee ligament, meniscal, or other soft-tissue injury (S80.0, S83 and all subdiagnoses). We then calculated the mean annual incidence over the 9-year period. As a secondary objective, we investigated potential seasonal variation.

Results

The annual incidence for males and females was 766 (95% CI: 742, 789) and 676 (649, 702) per 100,000 persons/year respectively. For males and females, the peak rate occurred in 15 to 19 year-olds (1698 per 100,000 men and 1464 per 100,000 women, respectively). In women, rates were lowest in the 25 to 34 year-old age range before rising again between the ages of 35 and 49 years. We found substantial seasonal variation, greatest in men, with peaks in March-May and August-October.

Conclusions

The incidence of clinically diagnosed soft-tissue knee injury peaks in adolescence and emerging adulthood. However, a range of knee injuries continue to occur across the adult lifespan including at ages when osteoarthritis is typically diagnosed and managed. The potential cumulative effect on osteoarthritis progression of these injuries may warrant further investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/ar4678) contains supplementary material, which is available to authorized users.