Impact of concurrent foot pain on health and functional status in people with knee osteoarthritis: data from the osteoarthritis initiative

Weight-bearing line at the ankle joint level shifted laterally after total knee arthroplasty for varus knee osteoarthritis: Evaluation of the hip-to-calcaneus line

BACKGROUND

Few studies have comprehensively examined how alignment beyond the ankle joint changes after Total knee arthroplasty (TKA). This retrospective study aimed to answer the questions: (1) do the radiological parameters beyond the ankle joint, including the weight-bearing line at the ankle joint level, change after TKA in varus knee osteoarthritis? (2) Does the lower extremity alignment correlate with alignment beyond the ankle joint?

HYPOTHESIS

Our hypothesis was that TKA altered the radiological parameters beyond the ankle, which correlated with the lower extremity alignment.

PATIENTS AND METHODS

This retrospective study included 67 patients who underwent mechanically aligned TKA for varus knee osteoarthritis. The hip-knee-ankle angle (HKA), tibial plafond inclination angle (TPIA), hindfoot alignment angle (HA), talar tilt (TT), and weight-bearing line at the ankle joint level (mechanical ankle joint axis point [MAJAP]) were measured using radiographs taken before and 6 months after TKA; each parameter was compared between the two time points. The correlations between HKA and other parameters were examined preoperatively and postoperatively.

RESULTS

The mean HKA, TPIA, HA, TT, and MAJAP changed significantly after TKA from 15.0±6.1̊ to 2.6̊±3.5̊, from 10.8̊±5.7̊ to 4.7̊±3.9̊, from 2.3̊±5.5̊ to -2.5̊±4.5̊, from 0.2̊±1.3̊ to -0.5̊±1.4̊, and from 29.3±23.3 to 54.3±20.6, respectively. Correlations were noted between the preoperative HKA and the preoperative TPIA (r=0.58), HA (r=0.36), and MAJAP (r=-0.59), and between the postoperative HKA and the postoperative TPIA (r=0.54) and MAJAP (r=-0.38).

DISCUSSION

TKA for varus knee osteoarthritis altered radiological parameters beyond the ankle, with the weight-bearing line at the ankle joint level passing more laterally. The weight-bearing line at the ankle joint level was correlated with lower extremity alignment both preoperatively and postoperatively.

LEVEL OF EVIDENCE

IV; single-centre retrospective observational study.

Biomechanical response of lower limb joints to lateral wedge insoles

Lateral wedge insole (LWI) is a frequently recommended treatment option for early and midterm stages of medial knee osteoarthritis. However, studies of its effects on the lower limb joints are incomplete and imperfect. The main purpose of this study was to quantitatively analyze the response of intervention of LWI on lower-limb joint kinematics, ground reaction forces (GRFs), and centre of pressure (COP). Gait analysis of 16 healthy subjects was conducted. Three-dimensional motion data and force plate measurements were collected in the control (barefoot) and experimental conditions (wearing a pair of assigned shoes with 0, 7, and 10 mm LWIs). Results showed that the peak knee flexion angle was increased by 3.43°, 3.09°, and 3.27° with 0, 7, and 10 mm LWIs, respectively (p < 0.01). The ankle peak dorsiflexion angle was significantly decreased by 3.79°, 2.19°, and 1.66° with 0, 7, and 10 mm LWIs, respectively (p = 0.02). The internal rotation angle was increased by 2.78°, 3.76°, and 4.58° with 0, 7, and 10 mm LWIs, respectively (p < 0.01). The forefoot with LWIs showed highly significantly smaller inversion, eversion, and adduction angles (all p < 0.01). The 1st peak of the vertical GRF (p = 0.016) also increased significantly by a maximum of 0.06 body weight (BW) with LWIs. These results indicated that biomechanical changes and limitations of lateral wedges insole should be analyzed in more detail, possibly leading to new guidelines for the design and application.

The prevalence of foot pain and association with baseline characteristics in people participating in education and supervised exercise for knee or hip osteoarthritis: a cross-sectional study of 26,003 participants from the GLA:D® registry

BACKGROUND

Osteoarthritis (OA) affecting the knee or hip is highly prevalent in the general population and has associated high disease burden. Early identification of modifiable risk factors that prevent, limit, or resolve disease symptoms is critical. Foot pain may represent a potentially modifiable factor however little is known about the prevalence of foot pain in people with knee or hip OA nor whether foot pain is associated with clinical characteristics. The main aim of this study was therefore to determine the prevalence of foot pain in people with knee or hip OA attending an education and supervised exercise-based intervention in Denmark (GLA:D®) and determine if baseline demographic or clinical characteristics are associated with foot pain.

METHODS

Analysis was conducted on baseline data of 26,003 people with symptomatic knee or hip OA completing a pain mannequin as part of the Good Life with osteoArthritis in Denmark (GLA:D®) primary care programme. Odds Ratios (OR) and 95% confidence intervals (CI) were calculated to estimate the strength of association between baseline clinical characteristics (including pain severity in worst knee/hip joint, number of painful knee/hip joints, pain medication use and physical activity level) and the presence of baseline foot pain.

RESULTS

Twelve percent of participants (n = 3,049) reported foot pain. In those people with index knee OA (n = 19,391), knee pain severity (OR 1.01 CI 1.00, 1.01), number of painful knee/hip joints (OR 1.67 CI 1.58, 1.79), and use of pain medication (OR 1.23 CI 1.12, 1.36) were statistically associated with foot pain. Excluding use of pain medication, similar associations were seen in those with index hip OA.

CONCLUSION

Twelve percent of people with knee or hip OA participating in GLA:D® had foot pain. Those with worse knee/hip pain, and greater number of painful joints were more likely to report foot pain. This study is the first to demonstrate a significant relationship between clinical characteristics and foot pain in people with knee or hip OA participating in education and supervised exercise. Future investigation should consider the role that foot pain may play on knee and hip related outcomes following therapeutic intervention.

Foot Pain is Common, But Frequently Improves 1 Year After Total Knee Arthroplasty

BACKGROUND

Osteoarthritis frequently affects multiple joints through the lower limbs. This study sought to examine the incidence of foot pain in subjects undergoing total knee arthroplasty (TKA) and determine if foot symptoms improved following surgery.

METHODS

Six hundred ten subjects undergoing TKA completed patient-reported outcome measures preoperatively, and at 6 and/or 12 months after surgery including the incidence and severity of foot or ankle pain, Knee Injury and Osteoarthritis Outcome Scores (KOOS) Joint Replacement, Oxford Knee Scores (OKS), EQ5D, and satisfaction.

RESULTS

Foot or ankle pain was reported in 45% before, 32% at 6 months, and 36% at 12 months after TKA. Of those with preoperative foot pain, 42% at 6 months and 50% at 12 months reported no foot pain after TKA, and the Visual Analog Scale severity reduced from a mean of 4.0 before to 1.7 after surgery. Those with preoperative foot pain had lower baseline KOOS (P = .001), OKS (P = .001), and more depression/anxiety (P = .010), but experienced equivalent postoperative KOOS, OKS, and satisfaction with surgery, compared to those without foot pain.

CONCLUSION

Foot or ankle pain was reported by nearly half of TKA subjects, but resolved after surgery in 50%. Those with preoperative foot pain experienced at least equivalent improvement in knee-related symptoms and mobility compared to those without foot pain. The presence of foot pain should not be a deterrent to TKA.

Foot and ankle pain and risk of incident knee osteoarthritis and knee pain: Data from the Multicentre Osteoarthritis Study

Objectives

To examine whether foot and/or ankle pain increases the risk of knee OA.

Design

We utilised longitudinal data from the Multicentre Osteoarthritis Study (MOST); a community-based cohort of risk factors for knee OA. Participants without frequent knee pain (clinic visit only) and radiographic knee OA (RKOA) at baseline and, with no evidence of inflammatory musculoskeletal disease and a history of knee-related surgery were followed for up to 84-months for incident outcomes; i) RKOA (Kellgren-Lawrence (KL) ≥2), ii) symptomatic RKOA (RKOA and frequent pain in the same knee) and iii) frequent knee pain only. At baseline, ankle and foot symptoms were assessed, with knee radiographs and symptoms also assessed at 30, 60 and 84-months. Our exposures included baseline ankle, foot, and ankle and foot pain (participant-level). Associations between foot and/or ankle pain and incident outcomes were assessed using multiple logistic regression, with adjustment for participant characteristics and ankle/foot pain.

Results

No statistically significant associations were observed between ankle, foot and, ankle and foot pain and incident RKOA, respectively. Ankle pain with (2.30, 95% CI 1.13 to 4.66) and without foot pain (OR: 2.53, 95% CI 1.34 to 4.80) were associated with increased odds of incident symptomatic RKOA and frequent knee pain. No statistically significant associations were observed between foot pain and these outcomes.

Conclusions

Ankle pain should be a focus point, more so than foot pain, in the management of knee OA. Future studies should include additional ankle joint-specific symptom questions to better elucidate the knee OA biomechanical pathway.

An exploration of changes in plantar pressure distributions during walking with standalone and supported lateral wedge insole designs

Background

Lateral wedge insoles (LWI), standalone or with medial arch support (supported-LWI), have been thoroughly investigated for their effects on modifying gait biomechanics for people with knee osteoarthritis. However, plantar pressure distribution between these insole types has not been investigated and could provide insight towards insole prescription with concomitant foot symptoms taken into consideration.

Methods

In a sample of healthy individuals (n = 40), in-shoe plantar pressure was measured during walking with LWI, with or without medial arch support (variable- and uniform-stiffness designs), and a flat control insole condition. Pressure data from the plantar surface of the foot were divided into seven regions: medial/lateral rearfoot, midfoot, medial/central/lateral forefoot, hallux. Plantar pressure outcomes assessed were the medial-lateral pressure index (MLPI) for the whole foot, and the peak pressure, pressure-time integral (PTI), and contact area in each plantar region. Comfort in each insole condition was rated as a change relative to the flat control insole condition. Repeated-measures analyses of variance were calculated to compare the plantar pressure outcomes between insole conditions.

Results

Regionally, medial rearfoot and forefoot pressure were reduced by all wedged insoles, with the variable-stiffness supported-wedge showing greater reductions than the standalone wedge. Lateral rearfoot and forefoot pressure were reduced by both supported-LWI, but unchanged by the standalone wedge. In the midfoot, the standalone wedge maintained pressure but reduced regional contact area, while both supported-LWI increased midfoot pressure and contact area. All LWI increased the MLPI, indicating a lateral shift in plantar pressure distribution throughout the weightbearing phase of gait. Comfort ratings were not significantly different between insole conditions.

Conclusions

Regional differences in plantar pressure may help determine an appropriate lateral wedge insole variation to avoid exacerbation of concomitant foot symptoms by minimizing pressure in symptomatic regions. Lateral shifts in plantar pressure distribution were observed in all laterally wedged conditions, including one supported-LWI that was previously shown to be biomechanically ineffective for modifying knee joint load distribution. Thus, shifts in foot centre of pressure may not be a primary mechanism by which LWI can modify knee joint load distribution for people with knee osteoarthritis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-021-00493-5.

Effects of Vitamin D Supplementation on Disabling Foot Pain in Patients With Symptomatic Knee Osteoarthritis

OBJECTIVE

The present study was undertaken to determine whether vitamin D supplementation or maintaining sufficient vitamin D level reduces foot pain over 2 years in patients with symptomatic knee osteoarthritis (OA).

METHODS

A post hoc study was conducted from a randomized, double-blind, placebo-controlled trial named the Vitamin D Effect on Osteoarthritis (VIDEO) study. Symptomatic knee OA patients with serum 25-hydroxyvitamin D levels between 12.5 nmoles/liter and 60 nmoles/liter were included and randomly allocated to either monthly vitamin D₃ or placebo treatment (1:1) for 2 years. Manchester Foot Pain and Disability Index (MFPDI) was used to evaluate foot pain and disabling foot pain was defined as at least 1 of the 10 functional limitation items (items 1-9 and 11) being documented as on "most/every day(s)" in the last month. A repeated-measures, mixed-effects model was used to analyze the change of MFPDI scores between groups adjusting for potential confounders.

RESULTS

A total of 413 patients with a mean age of 63.2 years (49.7% males) were enrolled and 340 completed the study. The mean MFPDI score was 22.8 ± 7.3, with 23.7% of participants having disabling foot pain at baseline. There were significant differences in MFPDI scores change between groups over 2 years, with more improvements in the vitamin D group than in the placebo group (-0.03 versus 1.30; P = 0.013) and more improvement in those maintaining sufficient vitamin D levels (n = 226) than those who did not (n = 114) (-0.09 versus 2.19; P = 0.001).

CONCLUSION

Vitamin D supplementation and maintenance of sufficient vitamin D levels may improve foot pain in those with knee OA.

Correlation between pain severity and levels of anxiety and depression in osteoarthritis patients: a systematic review and meta-analysis

OBJECTIVES

Osteoarthritis (OA) is a chronic degenerative musculoskeletal disease that causes articular damage and chronic pain, with a prevalence of up to 50% in individuals >60 years of age. Patients suffering from chronic painful conditions, including OA, also frequently report anxiety or depression. A systematic review and meta-analysis were performed to assess the correlation between pain severity and depressive and anxious symptomatology in OA patients.

METHODS

A systematic search was conducted using four databases (PubMed, Medline, Scopus, and Web of Science) from inception up to 14th January of 2020. We included original articles evaluating pain severity and anxiety and/or depression severity in OA-diagnosed patients. Detailed data were extracted from each study, including patients' characteristics and pain, anxiety, and depression severity. When available, the Pearson correlation coefficient between pain and depression severity and pain and anxiety severity was collected and a meta-analysis of random effects was applied.

RESULTS

This systematic review included 121 studies, with a total of 38085 participants. The mean age was 64.3 years old and subjects were predominantly female (63%). The most used scale to evaluate pain severity was the Western Ontario and the McMaster Universities Osteoarthritis Index, while for anxiety and depression, the Hospital Anxiety and Depression Scale was the most used. The meta-analysis showed a moderate positive correlation between pain severity and both anxious (r = 0.31, p < 0.001) and depressive symptomatology (r = 0.36, p < 0.001).

CONCLUSIONS

Our results demonstrate a significant correlation between pain and depression/anxiety severity in OA patients, highlighting the need for its routine evaluation by clinicians.

Frontal plane knee alignment mediates the effect of frontal plane rearfoot motion on knee joint load distribution during walking in people with medial knee osteoarthritis

OBJECTIVE

To examine the nature of differences in the relationship between frontal plane rearfoot kinematics and knee adduction moment (KAM) magnitudes.

DESIGN

Cross-sectional study resulting from a combination of overground walking biomechanics data obtained from participants with medial tibiofemoral osteoarthritis at two separate sites. Statistical models were created to examine the relationship between minimum frontal plane rearfoot angle (negative values = eversion) and different measures of the KAM, including examination of confounding, mediation, and effect modification from knee pain, radiographic disease severity, static rearfoot alignment, and frontal plane knee angle.

RESULTS

Bivariable relationships between minimum frontal plane rearfoot angle and the KAM showed consistent negative correlations (r = -0.411 to -0.447), indicating higher KAM magnitudes associated with the rearfoot in a more everted position during stance. However, the nature of this relationship appears to be mainly influenced by frontal plane knee kinematics. Specifically, frontal plane knee angle during gait was found to completely mediate the relationship between minimum frontal plane rearfoot angle and the KAM, and was also an effect modifier in this relationship. No other variable significantly altered the relationship.

CONCLUSIONS

While there does appear to be a moderate relationship between frontal plane rearfoot angle and the KAM, any differences in the magnitude of this relationship can likely be explained through an examination of frontal plane knee angle during walking. This finding suggests that interventions derived distal to the knee should account for the effect of frontal plane knee angle to have the desired effect on the KAM.

Heel pain in female patients with early knee osteoarthritis

Background

Multiple lower limb joint involvement is one of the most common and debilitating musculoskeletal conditions, while the complaints from both heel and knee pain are considered the most frequent. For that reason, in this cross-sectional study, the association between heel pain (HP) and early knee osteoarthritis (EKOA) was investigated; the most painful site and side of HP, the prevalence, and risk factors for disabling HP in patients with EKOA were identified.

Results

Bilateral HP (56%) and posterior HP (54%) were found to be the most prevalent complaints, and 66% of patients reported the HP to be non-disabling. There was a very high positive statistically significant correlation between the Manchester Foot Pain Disability Index (MFPDI) and both the Health Assessment Questionnaire (HAQ) and the total Western Ontario and McMaster University Osteoarthritis (WOMAC) score (p ≤ 0.001), while there was a high negative statistically significant correlation between MFPDI and quadriceps angle of the most affected knee (p = 0.002). A higher total WOMAC score (OR 1.077, 95% CI 1.014 to 1.145) significantly increases the risk of developing disabling HP, while wearing 2–3-cm heels during the past month was found to be protective against the development of disabling HP (odds ratio < 1).

Conclusion

Disabling HP was present in a third of patients with EKOA and HP, and it was associated with flat shoe wear as well as a high total WOMAC score. Also, it had a statistically significant correlation with varus knee mal-alignment. Furthermore, decreased functional ability in the presence of HP was found to lead to significant disability. Moreover, a striking finding in this study was the longer mean duration of HP compared to the duration of knee symptoms.

Lifetime occupation is not associated with radiographic osteoarthritis of the first metatarsophalangeal joint in a cohort study of UK women

OBJECTIVE

The study aim was to determine whether lifetime occupation was associated with the presence of radiographic osteoarthritis (ROA) of the first metatarsophalangeal joint (MTPJ) in women.

METHOD

Data were collected from the prospective, population-based Chingford 1000 Women study. This cohort of women, aged 45-64 years at inception, was established in 1989 from a single general practice in Chingford, UK. Data has subsequently been collected repeatedly. Data from baseline, year six and year ten was used for the purposes of this cross-sectional study. The primary outcome was the presence of dorsal view ROA of the first MTPJ. The main exposure was lifetime occupation, categorised according to levels of occupation previously defined via international consensus: 1. Sedentary, 2. Light, 3. Light manual, 4. Heavy manual. Logistic regression analyses were conducted to quantify the relationship between lifetime occupation type and the presence of ROA of the first MTPJ, adjusting for age, body mass index and lifetime high-heeled footwear use as potential interactive variables for each decade.

RESULTS

Data for 209 women were included within this study. The mean (SD) age was 57 (±5.2) years. Predominant lifetime occupation was reported as sedentary by 51.7%, as light by 0%, as light manual by 33.5% and as heavy manual by 14.8% of participants. There were no statistical associations between lifetime occupation type and the presence of ROA of the first MTPJ in either the unadjusted (OR = 0.99, CI = 0.78-1.26,P = 0.96) partially adjusted (for age and BMI; OR = 1.00, CI = 0.78-1.29, P = 0.99) or fully adjusted models (for age, BMI and lifetime high heel footwear use for each decade of working life (OR = 1.02, CI = 0.79-1.31, P = 0.91); high-heel footwear use up to 20s (OR = 0.83, CI = 0.71-1.31, P = 0.83); high-heel footwear use in 20-30s (OR = 1.00, CI = 0.75-1.3, P = 0.98); high-heel footwear use in 30-40s (OR = 1.00, CI = 0.70-1.42, P = 0.99); high-heel footwear use in 40-50s (OR = 0.90, CI = 0.58-1.40, P = 0.65); high-heel footwear use in 50s (OR = 0.63,CI = 0.36-1.09, P = 0.10).

CONCLUSIONS

The findings suggest that lifetime occupation is not associated with the presence of ROA of the fist metatarsophalangeal joint. There does not appear to be any interactive effect between lifetime occupation, lifetime high-heel footwear use, age or BMI and ROA of the first MTPJ. In later life a positive trend towards increased ROA in those who reported lifetime high-heel footwear use was noted and this may be worthy of further research.

Comparing the association of widespread pain, multi-joint pain and low back pain with measures of pain sensitization and function in people with knee osteoarthritis

INTRODUCTION/OBJECTIVES

To compare 1. measures of pain sensitization (PS) in people with widespread pain (WSP), multi-joint pain, low back pain (LBP) and knee osteoarthritis (KOA) only, in people with knee OA and 2. results of self-reported function and physical performance tests amongst these sub groups.

METHODOLOGY

Patients with knee OA consulting an orthopaedic surgeon were recruited from three Montreal area hospitals. A body homunculus was used to identify the presence of WSP (Y/N), multi-joint pain using a joint count (≥ 2 joints) and LBP (Y/N). Tests included pressure pain thresholds (PPT), temporal summation (TS), conditioned pain modulation and three physical performance tests. The Knee Injury and Osteoarthritis Outcome Score (KOOS) assessed self-reported function. Means were compared with Welch's ANOVA, post hoc tests and multiple regression analysis were performed.

RESULTS

Two hundred twenty-one participants were evaluated (mean age: 63.4 ± 9.9 years, females n = 135 (61.1%)). Those with WSP significantly differed from those with LBP on PPT mean - 1.4, 95%CI (- 2.4, - 0.4), TS 10.3 (2.1, 18.5) and the stair climb test (SCT) 5.6 (1.3, 9.9). Those with WSP significantly differed from those with KOA only on TS 9.5 (1.0, 18.1), SCT 6.3 (2.0, 10.6) and KOOS - 14.2 (- 26.5, - 2.0).

CONCLUSION

In patients with knee OA, those with WSP demonstrated greater degrees of PS compared with those with knee OA only, LBP and multi-joint pain. They also demonstrated a slower SCT compared with those with KOA only and LBP and decreased self-reported function compared with those with KOA only. These results should be confirmed in a longitudinal study.Key Points• In people with knee OA and widespread pain, measures of sensitization, self-reported function and physical performance were poorer compared with those with knee OA and LBP, knee OA and multi-joint pain or knee OA only.• Clinicians can consider these outcomes when planning management for these subgroups planning a comprehensive treatment program for this subgroup.

Association between musculoskeletal pain at multiple sites and objectively measured physical activity and work capacity: Results from UK Biobank study

OBJECTIVES

To describe the cross-sectional association between musculoskeletal pain at multiple sites and physical work capacity (PWC) and objectively measured physical activity (PA).

DESIGN

Observational study.

METHODS

Data from a subsample of the UK Biobank were utilised (n=9856; mean age 58.5 years, mean body mass index 30.2kg/m2, 62% female). PWC was measured by a bicycle ergometer and PA by an accelerometer. Pain experienced in hip, knee, back and neck/shoulder was collected by questionnaire. Linear regression modelling was used with adjustment for potential confounders to estimate the association between pain and PWC and PA.

RESULTS

Increase in number of painful sites was associated with lower PWC, moderate and vigorous PA and increased low intensity PA in a dose-response relationship (all p-values for trend ≤0.001) before and after adjustment for confounders. In site specific analyses, hip pain was associated with an increased low intensity PA (β 52.8min/week, 95% CI 2.3-103.2) and reduced moderate PA (β -50.1min/week, 95% CI -98.5 to -1.8). Knee pain was only associated with vigorous PA (β -5.7min/week, 95% CI -10.0 to -1.3). Pain at neck/shoulder pain and back were not independently associated with PWC and PA.

CONCLUSIONS

Greater number of painful sites is consistently associated with poorer PWC, increased low intensity PA and reduced moderate to vigorous PA. Clinicians should address the critical role of being physically active in managing chronic musculoskeletal pain and interventions targeting musculoskeletal pain may be needed to increase PA levels.

Effect of knee unloading shoes on regional plantar forces in people with symptomatic knee osteoarthritis - an exploratory study

Background

Knee 'unloading' footwear can reduce the external knee adduction moment in people with knee osteoarthritis, yet effects of these shoes on regional plantar forces are unknown. We evaluated the effects of unloading shoes on in-shoe regional plantar forces, and whether measures of foot posture and/or mobility moderate these effects in people with symptomatic knee osteoarthritis.

Methods

In this exploratory study 21 participants underwent testing while wearing knee unloading shoes (ASICS GEL-Melbourne OA) and conventional shoes in random order. Peak total forces were compared across conditions for: lateral heel, medial heel, lateral forefoot, and medial forefoot. Arch index, centre of pressure position and medial-lateral heel peak force ratio were also evaluated. Foot posture, foot mobility magnitude and navicular drop were separately added to the mixed linear model to investigate if these modified the effect of footwear on outcomes.

Results

Unloading shoes significantly increased lateral heel and lateral forefoot force (12.9 and 20.2% respectively, all P < 0.001), with concurrent decreases in the medial heel (8.9%, P = 0.001) and medial forefoot (9.9%, P = 0.005). Unloading shoes significantly shifted the centre of pressure anteriorly (4.7%, P < 0.001) and laterally (5.6%, P = 0.034), but did not affect the arch index (8.7%, P = 0.093). Foot posture, foot mobility magnitude and navicular drop did not moderate the effect of footwear on outcomes.

Conclusion

Compared to conventional shoes, unloading shoes caused a lateral shift in foot pressure and force patterns. Although these effects were not moderated by foot posture, FMM or navicular drop, variability in the individual increases in lateral heel force suggests participant characteristics other than foot posture may play a role.

Trial registration

ACTRN12613000851763. Registered 02 August 2013.

The association of knee structural pathology with pain at the knee is modified by pain at other sites in those with knee osteoarthritis

The objective of this study was to investigate the associations of knee structural abnormalities with different patterns of pain. A total of 891 participants (average age 63 years; range 50 to 80 years) participated in this study. Presence of pain at the neck, back, hands, shoulders, hips, knees, and feet was assessed by questionnaire. Participants were categorized as having no pain at any site (no pain), pain only at the knee (KP), pain at other sites but not the knee (OP), and pain at the knee and other sites (KOP). T1-weighted or T2-weighted MRI of the right knee was performed to measure cartilage defects, bone marrow lesions (BMLs), and effusion-synovitis. Osteophytes and joint space narrowing were assessed by X-ray. KP, KOP, and OP were, respectively, present in 3, 43, and 42% of the participants. In multivariable analyses, KOP was associated with the presence of cartilage defects, BMLs, and osteophytes (OR 3.57 (95% CI 1.78 to 7.14), 2.37 (1.27 to 4.43), and 2.87 (1.10 to 7.51), respectively) in those with radiographic knee OA. KP was also associated with presence of these structural abnormalities as well as effusion-synovitis, and these associations were much stronger. The associations between structural abnormalities and KOP were weaker than those with KP in those with radiographic knee OA. This suggests that mechanisms mediating the association between structural pathology, localized, and generalized pain may be different, and central sensitization is possibly involved in generalized pain. Pain at other sites needs to be considered in the management and treatment of OA-related pain.

Longitudinal association between foot and ankle symptoms and worsening of symptomatic radiographic knee osteoarthritis: data from the osteoarthritis initiative

OBJECTIVE

To assess whether foot and/or ankle symptoms are associated with an increased risk of worsening of knee pain and radiographic change in people with knee osteoarthritis (OA).

METHODS

The presence and laterality of foot/ankle symptoms were recorded at baseline in 1368 participants from the Osteoarthritis Initiative (OAI) with symptomatic radiographic knee OA. Knee pain severity (measured using the Western Ontario and McMaster Universities Osteoarthritis Index pain subscale) and minimum medial tibiofemoral joint space (minJSW) width measured on X-ray were assessed yearly over the subsequent 4 years. Associations between foot/ankle symptoms and worsening of (1) knee pain, and (2) both knee pain and minJSW (i.e., symptomatic radiographic knee OA) were assessed using logistic regression.

RESULTS

Foot/ankle symptoms in either foot/ankle significantly increased the odds of knee pain worsening (adjusted OR 1.54, 95% CI 1.25 to 1.91). Laterality analysis showed ipsilateral (adjusted OR 1.50, 95% CI 1.07 to 2.10), contralateral (adjusted OR 1.44, 95% CI 1.02 to 2.06) and bilateral foot/ankle symptoms (adjusted OR 1.61, 95% CI 1.22 to 2.13) were all associated with knee pain worsening in the follow up period. There was no association between foot/ankle symptoms and worsening of symptomatic radiographic knee OA.

CONCLUSION

The presence of foot/ankle symptoms in people with symptomatic radiographic knee OA was associated with increased risk of knee pain worsening, but not worsening of symptomatic radiographic knee OA, over the subsequent 4 years. Future studies should investigate whether treatment of foot/ankle symptoms reduces the risk of knee pain worsening in people with knee OA.

Knee joint kinetics in response to multiple three-dimensional printed, customised foot orthoses for the treatment of medial compartment knee osteoarthritis

The knee adduction moment is consistently used as a surrogate measure of medial compartment loading. Foot orthoses are designed to reduce knee adduction moment via lateral wedging. The ‘dose’ of wedging required to optimally unload the affected compartment is unknown and variable between individuals. This study explores a personalised approach via three-dimensional printed foot orthotics to assess the biomechanical response when two design variables are altered: orthotic length and lateral wedging. Foot orthoses were created for 10 individuals with symptomatic medial knee osteoarthritis and 10 controls. Computer-aided design software was used to design four full and four three-quarter-length foot orthoses per participant each with lateral posting of 0° ‘neutral’, 5° rearfoot, 10° rearfoot and 5° forefoot/10° rearfoot. Three-dimensional printers were used to manufacture all foot orthoses. Three-dimensional gait analyses were performed and selected knee kinetics were analysed: first peak knee adduction moment, second peak knee adduction moment, first knee flexion moment and knee adduction moment impulse. Full-length foot orthoses provided greater reductions in first peak knee adduction moment (p = 0.038), second peak knee adduction moment (p = 0.018) and knee adduction moment impulse (p = 0.022) compared to three-quarter-length foot orthoses. Dose effect of lateral wedging was found for first peak knee adduction moment (p < 0.001), second peak knee adduction moment (p < 0.001) and knee adduction moment impulse (p < 0.001) indicating greater unloading for higher wedging angles. Significant interaction effects were found for foot orthosis length and participant group in second peak knee adduction moment (p = 0.028) and knee adduction moment impulse (p = 0.036). Significant interaction effects were found between orthotic length and wedging condition for second peak knee adduction moment (p = 0.002). No significant changes in first knee flexion moment were found. Individual heterogeneous responses to foot orthosis conditions were observed for first peak knee adduction moment, second peak knee adduction moment and knee adduction moment impulse. Biomechanical response is highly variable with personalised foot orthoses. Findings indicate that the tailoring of a personalised intervention could provide an additional benefit over standard interventions and that a three-dimensional printing approach to foot orthosis manufacturing is a viable alternative to the standard methods.

Association of frontal plane knee alignment with foot posture in patients with medial knee osteoarthritis

Background

To examine the association of radiographic frontal plane knee alignment with three-dimensional foot posture in patients with medial knee osteoarthritis (OA).

Methods

Participants in orthopedic clinics with Kellgren/Lawrence (K/L) grade ≥1 (88 patients and 88 knees; age, 61–91 years; 65.9% female) were enrolled. An anteroposterior radiographic view was used to assess the anatomical axis angle (AAA) after subtracting a sex-specific correction factor. The three-dimensional foot posture was also evaluated.

Results

Multiple regression analyses showed that increased corrected AAA (i.e., valgus direction) was independently associated with a decrease in the hallux valgus angle (regression coefficient: −0.40 per degree, 95% confidence interval [CI]: −0.72, −0.09; P = 0.013) and increase in the pronation angle of the calcaneus relative to floor (regression coefficient: 0.33 per degree, 95% CI: 0.10, 0.56; P = 0.005) adjusted for age, sex, and body mass index. The relationship between the corrected AAA and hallux valgus angle strengthened (regression coefficient: −0.60 per degree, 95% CI: −1.08, −0.13; P = 0.014) in varus-aligned knees examined separately (63 knees). The other foot postures (navicular height, navicular height/foot length, and rearfoot angle) were not significantly associated with corrected AAA.

Conclusions

Radiographic frontal plane knee alignment was associated with hallux valgus angle and calcaneus angle relative to the floor in patients with medial knee OA, particularly in varus-aligned knees. These results indicate a connection between altered frontal knee alignment and foot posture, which may be helpful in understanding the pathogenesis of altered foot posture observed in patients with knee OA.

Lateral wedges with and without custom arch support for people with medial knee osteoarthritis and pronated feet: an exploratory randomized crossover study

BACKGROUND

Pronated foot posture is associated with many clinical and biomechanical outcomes unique to medial compartment knee osteoarthritis (OA). Though shoe-worn insole treatment, including lateral wedges, is commonly studied in this patient population, their effects on the specific subgroup of people with medial knee OA and concomitant pronated feet are unknown. The purpose of this study was to evaluate whether lateral wedge insoles with custom arch support are more beneficial than lateral wedge insoles alone for knee and foot symptoms in people with medial tibiofemoral knee osteoarthritis (OA) and pronated feet.

METHODS

Twenty-six people with pronated feet and symptomatic medial knee OA participated in a randomized crossover study comparing five degree lateral wedge foot insoles with and without custom foot arch support. Each intervention was worn for two months, separated by a two-month washout period of no insoles wear. Main outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and physical function subscales, the revised short-form Foot Function Index (FFI-R) pain and stiffness subscales, and the timed stair climb test. Regression modeling was conducted to examine treatment, period, and interaction effects.

RESULTS

Twenty-two participants completed the study, and no carryover or interaction effects were observed for any outcome. Significant treatment effects were observed for the timed stair climb, with greater improvements seen with the lateral wedges with arch support. Within-condition significant improvements were observed for WOMAC pain and physical function, as well as FFI-R pain and stiffness with lateral wedges with arch support use. More adverse effects were reported with the lateral wedges alone, while more people preferred the lateral wedges with arch support overall.

CONCLUSIONS

Addition of custom arch support to a standard lateral wedge insole may improve foot and knee symptoms in people with knee OA and concomitant pronated feet. These preliminary findings suggest further research evaluating the role of shoe-worn insoles for treatment of this specific sub-group of people with knee OA is warranted.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02234895.

The relationship between foot and ankle symptoms and risk of developing knee osteoarthritis: data from the osteoarthritis initiative

OBJECTIVE

To investigate whether foot and/or ankle symptoms increase the risk of developing (1) knee symptoms and (2) symptomatic radiographic knee osteoarthritis (OA).

DESIGN

1020 Osteoarthritis Initiative (OAI) participants who were at-risk of knee OA, but were without knee symptoms or radiographic knee OA, were investigated. Participants indicated the presence and laterality of foot/ankle symptoms at baseline. The main outcome was development of knee symptoms (pain, aching or stiffness in and around the knee on most days of the month for at least 1 month in the past year). A secondary outcome was development of symptomatic radiographic knee OA (symptoms plus Kellgren and Lawrence [KL] grade ≥2), over the subsequent 4 years. Associations between foot/ankle symptoms and study outcomes were assessed by logistic regression models.

RESULTS

Foot/ankle symptoms in either or both feet significantly increased the odds of developing knee symptoms (adjusted odds ratio (OR) 1.55, 95% confidence interval (CI) 1.10 to 2.19), and developing symptomatic radiographic knee OA (adjusted OR 3.28, 95% CI 1.69 to 6.37). Based on laterality, contralateral foot/ankle symptoms were associated with developing both knee symptoms (adjusted OR 1.68, 95% CI 1.05 to 2.68) and symptomatic radiographic knee OA (adjusted OR 3.08, 95% CI 1.06 to 8.98), whilst bilateral foot/ankle symptoms were associated with developing symptomatic radiographic knee OA (adjusted OR 4.02, 95% CI 1.76 to 9.17).

CONCLUSION

In individuals at-risk of knee OA, the presence of contralateral foot/ankle symptoms in particular increases risk of developing both knee symptoms and symptomatic radiographic knee OA.

Association Between Pain at Sites Outside the Knee and Knee Cartilage Volume Loss in Elderly People Without Knee Osteoarthritis: A Prospective Study

OBJECTIVE

Pain is common in the elderly. Knee pain may predict knee cartilage loss, but whether generalized pain is associated with knee cartilage loss is unclear. This study, therefore, aimed to determine whether pain at multiple sites predicts knee cartilage volume loss among community-dwelling older adults, and, if so, to explore potential mechanisms.

METHODS

Data from the prospective Tasmanian Older Adult Cohort study was utilized (n = 394, mean age 63 years, range 52-79 years). Experience of pain at multiple sites was assessed using a questionnaire at baseline. T1-weighted fat-saturated magnetic resonance imaging of the right knee was performed to assess the cartilage volume at baseline and after 2.6 years. Linear regression modeling was used with adjustment for potential confounders.

RESULTS

The median number of painful sites was 3 (range 0-7). There was a dose-response relationship between the number of painful sites and knee cartilage volume loss in the lateral and total tibiofemoral compartments (lateral β = -0.28% per annum; total β = -0.25% per annum, both P for trend < 0.05), but not in the medial compartment. These associations were stronger in participants without radiographic knee osteoarthritis (OA) (P < 0.05) and independent of age, sex, body mass index, physical activity, pain medication, and knee structural abnormalities.

CONCLUSION

The number of painful sites independently predicts knee cartilage volume loss, especially in people without knee OA, suggesting that widespread pain may be an early marker of more rapid knee cartilage loss in those without radiographic knee OA. The underlying mechanism is unclear, but it is independent of anthropometrics, physical activity, and knee structural abnormalities.

Preventing the development of SLE: identifying risk factors and proposing pathways for clinical care

Although challenging, developing evidence-based approaches to an early and accurate diagnosis of systemic lupus erythematosus is a key approach to preventing disease and lupus-associated morbidity and mortality. Advances in our understanding of preclinical and incomplete lupus erythematosus have enabled the identification of risk factors that may predict disease and the development of potential strategies aimed at primary prevention. Emerging data support the notion that there is a temporal disease progression from initial asymptomatic autoimmunity (preclinical lupus) through early clinical features of the disease (incomplete lupus erythematosus) to finally becoming fully classifiable systemic lupus erythematosus (complete lupus erythematosus). Here, we review the demographic, clinical, biomarker as well as genetic and environmental features that are reported to increase the risk of disease progression. Based on these risk factors, we propose a clinical care pathway for patients with early disease. We envisage that such a pathway, through early identification of disease, may improve patient outcomes, while reducing health care costs.

Knee and ankle biomechanics with lateral wedges with and without a custom arch support in those with medial knee osteoarthritis and flat feet

This study compared immediate changes in knee and ankle/subtalar biomechanics with lateral wedge orthotics with and without custom arch support in people with knee osteoarthritis and flat feet. Twenty-six participants with radiographic evidence of medial knee osteoarthritis (22 females; age 64.0 years [SD 8.0 years], BMI 27.2 kg/m(2) [4.2]) and flat feet (median foot posture index = + 5) underwent three-dimensional gait analysis for three conditions: Control (no orthotic), lateral wedge, and lateral wedge plus arch support. Condition order was randomized. Outcomes included frontal plane knee and ankle/subtalar biomechanics, and comfort. Compared to the control, lateral wedge and lateral wedge with arch support reduced the knee adduction moment impulse by 8% and 6%, respectively (p < 0.05). However, the lateral wedge resulted in a more everted foot position (4.3 degrees) than lateral wedge plus arch support (3.2 degrees) (p < 0.05). In contrast, lateral wedge plus arch support reduced foot frontal plane excursion compared to other conditions (p < 0.05). Participants self-reported significantly more immediate comfort with lateral wedge plus arch support compared to the control, whereas there was no difference in self-reported comfort between lateral wedge and control. No immediate changes in knee pain were observed in any condition.

CLINICAL SIGNIFICANCE

Rather than prescribing lateral wedges to all patients with knee osteoarthritis, those who have medial knee osteoarthritis and flat feet may prefer to use the combined orthotic to reduce loads across the knee, and to minimize the risk of foot and ankle symptoms as a consequence of orthotic treatment. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1597-1605, 2016.

Osteoarthritis year in review 2015: clinical

The purpose of this review is to highlight clinical research in osteoarthritis (OA). A literature search was conducted using PubMed (http://www.ncbi.nlm.nih.gov/pubmed/) with the search terms "osteoarthritis [All Fields] AND treatment [All Fields]" and the following limits activated: humans, English language, all adult 19+ years, published between April 1, 2014 and April 1, 2015. A second literature search was then conducted with the search terms "osteoarthritis [All Fields] AND epidemiology [All Fields]", with the same limits. Reports of surgical outcome, case series, surgical technique, tissue sample or culture studies, trial protocols, and pilot studies were excluded. Of 1523, 150 were considered relevant. Among epidemiologic and observational clinical studies, themes included physical activity, early knee OA, and confidence/instability/falls. Symptom outcomes of pharmacologic treatments were reported for methotrexate, adalimumab, anti-nerve growth factor monoclonal antibodies, strontium ranelate, bisphosphonates, glucosamine, and chondroitin sulfate, and structural outcomes of pharmacologic treatments for strontium ranelate, recombinant human fibroblast growth factor 18, and glucosamine and chondroitin sulfate. Symptom outcomes of non-pharmacologic interventions were reported for: neuromuscular exercise, quadriceps strengthening, weight reduction and maintenance, TENS, therapeutic ultrasound, stepped care strategies, cognitive behavior therapy for sleep disturbance, acupuncture, gait modification, booster physical therapy, a web-based therapeutic exercise resource center for knee OA; hip physical therapy for hip OA; and joint protection and hand exercises for hand OA. Structure outcomes of non-pharmacologic interventions were reported for patellofemoral bracing.