Is lifelong knee joint force from work, home, and sport related to knee osteoarthritis?

A systematic review of the sex differences in risk factors for knee osteoarthritis

OBJECTIVES

Previous systematic reviews focused on the evidence of common risk factors for knee OA (KOA); however, the effect and strength of association between risk factors and KOA might be different between the two sexes. The aim of the present systematic review was to determine the current evidence on sex differences in the association between risk factors and KOA and their prevalence.

METHODS

We searched the following electronic bibliographic databases: MEDLINE (PubMed), EMBASE and Web of Science. A methodological quality assessment was conducted independently by two researchers according to an adapted version of the standardized set of criteria known as the Newcastle-Ottawa Quality Assessment Scale (NOS). The NOS, a star system, was converted to three categories of quality.

RESULTS

In total, 27 studies reported sex-specific risk estimates on several risk factors for KOA. Out of the 22 longitudinal cohort studies (except one nested case-control), 12 were of good quality and 10 were of fair quality. The five cross-sectional studies consisted of one of good, three of fair and one of poor quality. There was an indication of sex differences in risk factors leading to higher risk of KOA: high BMI, alcohol consumption, atherosclerosis and high vitamin E levels in women, and high physical activity, soft drink consumption and abdominal obesity in men. Knee injury, high blood pressure and low step rate seem to affect both women and men.

CONCLUSION

More good quality studies are needed to assess sex differences in risk factors for KOA, especially for symptomatic/clinical OA.

Simulated Tibiofemoral Joint Reaction Forces for Three Previously Studied Gait Modifications in Healthy Controls

Gait modifications, such as lateral trunk lean (LTL), medial knee thrust (MKT), and toe-in gait (TIG), are frequently investigated interventions used to slow the progression of knee osteoarthritis. The Lerner knee model was developed to estimate the tibiofemoral joint reaction forces (JRF) in the medial and lateral compartments during gait. These models may be useful for estimating the effects on the JRF in the knee as a result of gait modifications. We hypothesized that all gait modifications would decrease the JRF compared to normal gait. Twenty healthy individuals volunteered for this study (26.7 ± 4.7 years, 1.75 ± 0.1 m, 73.4 ± 12.4 kg). Ten trials were collected for normal gait as well as for the three gait modifications: LTL, MKT, and TIG. The data were used to estimate the JRF in the first and second peaks for the medial and lateral compartments of the knee via opensim using the Lerner knee model. No significant difference from baseline was found for the first peak in the medial compartment. There was a decrease in JRF in the medial compartment during the loading phase of gait for TIG (6.6%) and LTL (4.9%) and an increasing JRF for MKT (2.6%). but none was statistically significant. A significant increase from baseline was found for TIG (5.8%) in the medial second peak. We found a large variation in individual responses to gait interventions, which may help explain the lack of statistically significant results. Possible factors influencing these wide ranges of responses to gait modifications include static alignment and the impacts of variation in muscle coordination strategies used, by participants, to implement gait modifications.

Men and Women's Occupational Activities and the Risk of Developing Osteoarthritis of the Knee, Hip, or Hands: A Systematic Review and Recommendations for Future Research

Objective

To systematically review the evidence for an increased risk of osteoarthritis in the hip, knee, hand, wrist, finger, ankle, foot, shoulder, neck, and spine related to diverse occupational activities of men and women and to examine dose‐response information related to the frequency, intensity, and duration of work exposures and the risk of osteoarthritis (OA).

Methods

Established guidelines for systematic reviews in occupational health and safety studies were followed. MEDLINE, Embase, CINAHL, and Cochrane Library were searched from inception to December 2017. Studies were reviewed for relevance, quality was appraised, and data were extracted and synthesized.

Results

Sixty‐nine studies from 23 countries yielded strong and moderate evidence for lifting, cumulative physical loads, full‐body vibration, and kneeling/squatting/bending as increasing the risks of developing OA in men and women. Strong and moderate evidence existed for no increased risk of OA related to sitting, standing, and walking (hip and knee OA), lifting and carrying (knee OA), climbing ladders (knee OA), driving (knee OA), and highly repetitive tasks (hand OA). Variability in dose‐response data resulted in an inability to synthesize these data.

Conclusion

Evidence points to the potential for OA occupational recommendations and practice considerations to be developed for women and men. However, research attention is needed to overcome deficits in the measurement and recall of specific work activities so that recommendations and practice considerations can provide the specificity needed to be adopted in workplaces.

Physical activity and osteoarthritis: a consensus study to harmonise self-reporting methods of physical activity across international cohorts

Physical activity (PA) is increasingly recognised as an important factor within studies of osteoarthritis (OA). However, subjective methods used to assess PA are highly variable and have not been developed for use within studies of OA, which creates difficulties when comparing and interpreting PA data in OA research. The aim of this study was, therefore, to gain expert agreement on the appropriate methods to harmonise PA data among existing population cohorts to enable the investigation of the association of PA and OA. The definition of PA in an OA context and methods of harmonization were established via an international expert consensus meeting and modified Delphi exercise using a geographically diverse committee selected on the basis of individual expertise in physical activity, exercise medicine, and OA. Agreement was met for all aims of study: (1) The use of Metabolic Equivalent of Task (MET) minutes per week (MET-min/week) as a method for harmonising PA variables among cohorts; (2) The determination of methods for treating missing components of MET-min/week calculation; a value will be produced from comparable activities within a representative cohort; (3) Exclusion of the domain of occupation from total MET-min/week; (4) The need for a specific measure of joint loading of an activity in addition to intensity and time, in studies of diseases, such as OA. This study has developed a systematic method to classify and harmonise PA in existing OA cohorts. It also provides minimum requirements for future studies intending to include subjective PA measures.

HIGH REPETITION JUMP TRAINING COUPLED WITH BODY WEIGHT SUPPORT IN A PATIENT WITH KNEE PAIN AND PRIOR HISTORY OF ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: A CASE REPORT

BACKGROUND AND PURPOSE

Patients frequently experience long-term deficits in functional activity following anterior cruciate ligament reconstruction, and commonly present with decreased confidence and poor weight acceptance in the surgical knee. Adaptation of neuromuscular behaviors may be possible through plyometric training. Body weight support decreases intensity of landing sufficiently to allow increased training repetition. The purpose of this case report is to report the outcomes of a subject with a previous history of anterior cruciate ligament (ACL) reconstruction treated with high repetition jump training coupled with body weight support (BWS) as a primary intervention strategy.

CASE DESCRIPTION

A 23-year old female, who had right ACL reconstruction seven years prior, presented with anterior knee pain and effusion following initiation of a running program. Following visual assessment of poor mechanics in single leg closed chain activities, landing mechanics were assessed using 3-D motion analysis of single leg landing off a 20 cm box. She then participated in an eight-week plyometric training program using a custom-designed body weight support system. The International Knee Documentation Committee Subjective Knee Form (IKDC) and the ACL-Return to Sport Index (ACL-RSI) were administered at the start and end of treatment as well as at follow-up testing.

OUTCOMES

The subject's IKDC and ACL-RSI scores increased with training from 68% and 43% to 90% and 84%, respectively, and were retained at follow-up testing. Peak knee and hip flexion angles during landing increased from 47 ° and 53 ° to 72 ° and 80 ° respectively. Vertical ground reaction forces in landing decreased with training from 3.8 N/kg to 3.2 N/kg. All changes were retained two months following completion of training.

DISCUSSION

The subject experienced meaningful changes in overall function. Retention of mechanical changes suggests that her new landing strategy had become a habitual pattern. Success with high volume plyometric training is possible when using BWS. Clinical investigation into the efficacy of body weight support as a training mechanism is needed.

LEVEL OF EVIDENCE

Level 4 - Case Report.

THE USE OF FUNCTIONAL TESTS TO PREDICT SAGITTAL PLANE KNEE KINEMATICS IN NCAA-D1 FEMALE ATHLETES

BACKGROUND

Landing with the knee in extension places increased loads on ligamentous restraints at the knee versus landing in flexion. Unfortunately, existing methods to predict landing kinematics require sophisticated equipment and expertise. The purpose of this study was to develop predictive models for sagittal plane tibiofemoral landing kinematics from the results of functional tests.

METHODS

Twenty-nine female, NCAA-D1 college athletes (mean ± standard deviation, age = 19.03 ± 1.09; mass=66.56 ± 13.47 kg; height = 171.16 ± 7.92 cm) participated in a descriptive, laboratory study. Participants performed five unilateral, dominant lower extremity (LE) landings from a 35cm platform onto a forceplate. LE three-dimensional kinematics were captured with electromagnetic sensors interfaced with motion analysis software. Then in a randomized order, participants performed three standardized functional tests: single limb triple hop (SLTH), countermovement vertical jump (CMVJ) and the Margaria-Kalamen (MK) test. Sagittal plane tibiofemoral joint angle at initial contact (IC) and excursion (EXC) in the first 0.1s after ground contact were entered into a statistical software package. Multiple linear regression analyses generated one model predicting IC and one predicting EXC from the independent variables. Alpha levels were set a priori at p ≤ .05.

RESULTS

A two variable (MK, SLTH) linear regression model that predicted EXC was significant (Adjusted R (2) = .213, p = .017), however the model that predicted IC was not (p = .890).

CONCLUSION

Knee flexion excursion following a single leg landing task may be predicted with the MK and SLTH. The use of functional tests provides a practical means to predict landing kinematics to clinicians working with an active, athletic population.

LEVEL OF EVIDENCE

3, cohort study.

The influence of long-term exposure and timing of physical activity on new joint pain and stiffness in mid-age women

OBJECTIVE

To examine the influence of long-term exposure and timing of physical activity (PA) on new joint pain/stiffness in mid-age women.

METHODS

Data were from 5105 participants (born 1946-51) in the Australian Longitudinal Study on Women's Health (ALSWH) who completed survey items on PA (1998, 2001 and 2004) and joint pain/stiffness (2007 and 2010). PA was categorized in five levels at each survey and summed into a cumulative PA score (CPA, range 0-12). Associations were analysed using logistic regression, with separate models for the cumulative model (using CPA), the sensitive periods model (i.e., PA measured at each survey in one regression model) and the critical periods model (i.e., separate regression models for PA at each survey).

RESULTS

951 (18.6%) participants reported new-onset joint pain/stiffness. In the cumulative model, CPA was associated joint pain/stiffness when included as a continuous variable (adjusted odds ratio [OR] = 0.97, 95% confidence interval [CI] = 0.95-0.99), but not when included as a categorical variable. In both the sensitive periods and critical periods models, low to high levels of PA in 2001 and 2004 had stronger inverse associations with joint pain/stiffness than PA levels in 1998. The model fit was better for the sensitive periods than the cumulative or critical periods models.

CONCLUSIONS

In mid-age women, PA between the ages 47 and 58 was associated with a lower risk of joint pain/stiffness 9 years later. Associations were stronger for PA in the last 6 years than for earlier PA.

Knee osteoarthritis: Clinical connections to articular cartilage structure and function

Articular cartilage is a unique biphasic material that supports a lifetime of compressive and shear forces across joints. When articular cartilage deteriorates, whether due to injury, wear and tear or normal aging, osteoarthritis and resultant pain can ensue. Understanding the basic science of the structure and biomechanics of articular cartilage can help clinicians guide their patients to appropriate activity and loading choices. The purpose of this article is to examine how articular cartilage structure and mechanics, may interact with risk factors to contribute to OA and how this interaction provides guidelines for intervention choices This paper will review the microstructure of articular cartilage, its mechanical properties and link this information to clinical decision making.

Factors contributing to inherent varus alignment of lower limb in normal Asian adults: role of tibial plateau inclination

PURPOSE

This prospective study aimed to evaluate radiographically, mechanical or hip-knee-ankle (HKA) axis in healthy, asymptomatic, Asian (Indian and Korean) adults between 20 and 40 years of age to determine the incidence of inherent varus (mechanical limb alignment of >3° varus) and the factors influencing it.

METHODS

Three hundred and eighty-eight lower limbs were evaluated using full length, standing hip-to-ankle radiographs in 198 healthy, asymptomatic, Asian (Indian and Korean) adults between 20 and 40 years of age to assess the hip-knee-ankle (HKA) angle, medial proximal tibial angle (MPTA), femoral bowing and femoral neck-shaft angle to determine the incidence of inherent varus (mechanical limb alignment of >3° varus) and the factors influencing it.

RESULTS

Overall, the mean HKA angle was 177.6°±2.6° with 34.5% of limbs in inherent varus (mean HKA angle 174.9°±1.8°). The incidence of inherent varus was significantly higher (p=0.01) in males (40%) compared to females (28%) but similar among Indian (34%) and Korean subjects (35%). The hip-knee-ankle (HKA) angle showed significant positive correlation (r=0.82, p<0.001) with only the medial proximal tibial angle (MPTA).

CONCLUSIONS

Inherent varus alignment of the lower limb is fairly common among asymptomatic, Asian adults. These results raise several pertinent questions regarding the role of inherent varus in the aetiopathogenesis of knee osteoarthritis and in lower limb realignment procedures.