Do comorbidities predict pain and function in knee osteoarthritis following an exercise intervention, and do they moderate the effect of exercise? Analyses of data from three randomized controlled trials

Frailty predicts knee pain trajectory over 9 years: results from the Osteoarthritis Initiative

OBJECTIVE

Frailty is a multisystem syndrome and its relationship with symptomatic osteoarthritis has been reported. We aimed to identify trajectories of knee pain in a large prospective cohort and to describe the effect of frailty status at baseline on the pain trajectories over 9 years.

METHODS

We included 4419 participants (mean age 61.3 years, 58% female) from the Osteoarthritis Initiative cohort. Participants were classified as "no frailty," "pre-frailty," or "frailty" at baseline, based on 5 characteristics (ie, unintentional weight loss, exhaustion, weak energy, slow gait speed, and low physical activity). Knee pain was evaluated annually using the Western Ontario and McMaster Universities Osteoarthritis Index pain subscale (0-20) from baseline to 9 years.

RESULTS

Of the participants included, 38.4%, 55.4%, and 6.3% were classified as "no frailty," "pre-frailty," and "frailty," respectively. Five pain trajectories were identified: "No pain" (n = 1010, 22.8%), "Mild pain" (n = 1656, 37.3%), "Moderate pain" (n = 1149, 26.0%), "Severe pain" (n = 477, 10.9%), and "Very Severe pain" (n = 127, 3.0%). Compared to participants with no frailty, those with pre-frailty and frailty were more likely to have more severe pain trajectories (pre-frailty: odds ratios [ORs] 1.5 to 2.1; frailty: ORs 1.5 to 5.0), after adjusting for potential confounders. Further analyses indicated that the associations between frailty and pain were mainly driven by exhaustion, slow gait speed, and weak energy.

CONCLUSIONS

Approximately two-thirds of middle-aged and older adults were frail or pre-frail. The role of frailty in predicting pain trajectories suggests that frailty may be an important treatment target for knee pain.

Interpretation threshold values for patient-reported outcomes in patients participating in a digitally delivered first-line treatment program for hip or knee osteoarthritis

Objective

Establish proportions of patients reporting important improvement, acceptable symptoms and treatment failure and define interpretation threshold values for pain, patient-reported function and quality-of-life after participating in digital first-line treatment including education and exercise for hip and knee osteoarthritis (OA).

Methods

Observational study. Responses to the pain Numeric Rating Scale (NRS, 0-10 best to worst), Knee injury and Osteoarthritis Outcome Score 12 (KOOS-12) and Hip disability and Osteoarthritis Outcome Score 12 (HOOS-12, both 0-100 worst to best) were obtained for 4383 (2987) and 2041 (1264) participants with knee (hip) OA at 3 and 12 months post intervention. Threshold values for Minimal Important Change (MIC), Patient Acceptable Symptom State (PASS) and Treatment Failure (TF) were estimated using anchor-based predictive modeling.

Results

70-85% reported an important improvement in pain, function and quality of life after 3 and 12 months follow-up. 42% (3 months) and 51% (12 months) considered their current state as satisfactory, whereas 2-4% considered treatment failed. MIC values were -1 (NRS) and 0-4 (KOOS/HOOS-12) across follow-ups and joint affected. PASS threshold value for NRS was 3, and 53-73 for the KOOS/HOOS-12 subscales Corresponding values for TF were 5 (NRS) and 34-55 (KOOS/HOOS-12). Patients with more severe pain at baseline had higher MIC scores and accepted poorer outcomes at follow-ups.

Conclusion

Threshold estimates aid in the interpretation of outcomes after first-line OA interventions assessed with NRS Pain and KOOS/HOOS-12. Baseline pain severity is important to consider when interpreting threshold values after first-line interventions in these patients.

Absence of Improvement With Exercise in Some Patients With Knee Osteoarthritis: A Qualitative Study of Responders and Nonresponders

OBJECTIVE

To compare the perceptions of patients about why they did, or did not, respond to a physical therapist-supported exercise and physical activity program.

METHODS

This was a qualitative study within a randomized controlled trial. Twenty-six participants (of 40 invited) with knee osteoarthritis sampled according to response (n = 12 responders, and 14 nonresponders based on changes in both pain and physical function at 3 and 9 months after baseline) to an exercise and physical activity intervention. Semistructured individual interviews were conducted. Inductive thematic analysis was undertaken within each subgroup using grounded theory principles. A deductive approach compared themes and subthemes across subgroups. Findings were triangulated with quantitative data.

RESULTS

(Sub)themes common to responders and nonresponders included the intervention components that facilitated engagement, personal attitudes and expectations, beliefs about osteoarthritis and exercise role, importance of adherence, and perceived strength gains with exercise. In contrast to responders who felt empowered to self-manage, nonresponders accepted responsibility for lack of improvement in pain and function with exercise, acknowledging that their adherence to the intervention was suboptimal (confirmed by quantitative adherence data). Nonresponders believed that their excess body weight (supported by quantitative data) contributed to their outcomes, encountered exercise barriers (comorbidities, stressors, and life events), and perceived that the trial measurement tools did not adequately capture their response to exercise.

CONCLUSION

Responders and nonresponders shared some similar perceptions of exercise. However, along with perceived limitations in trial outcome measurements, nonresponders encountered challenges with excess weight, comorbidities, stressors, and life events that led to suboptimal adherence and collectively were perceived to contribute to nonresponse.

Influence of Risk Factors on the Well-Being of Elderly Women with Knee Osteoarthritis

Background and Objectives: Knee osteoarthritis (KOA) is a widespread chronic joint disease characterized by functional limitations and pain. Functioning restrictions exert a detrimental impact on societal integration, relationships, and psychological well-being, resulting in significant emotional distress in KOA patients. The objective of this study is to examine how various risk factors impact the emotional well-being of individuals with KOA. Materials and Methods: This prospective cross-sectional study involved 154 postmenopausal women treated at the Special Hospital for Rheumatic Diseases in Novi Sad, Serbia. The experimental group comprised 97 individuals with chronic knee pain and structural knee damage (Kellgren-Lawrence (KL) scale II-IV), while the control group had 53 individuals with chronic knee pain but no structural knee damage (KL scale 0-I). The collected data consisted of sociodemographic factors, general characteristics, associated diseases, and laboratory results. Adequate anthropometric measurements were conducted, and all subjects were required to complete the SF-36 RAND questionnaire. Results: The analysis identified several variables that independently influenced emotional well-being. These included pain intensity (beta (β) 0.21; 95% CI: 0.03-0.20; p < 0.01), social functioning (beta (β) 0.47; 95% CI: 0.23-0.43; p < 0.001), physical functioning (beta (β) 0.23; 95% CI: 0.04-0.21; p < 0.01), and education level (8-12 years: beta (β) 0.25; 95% CI: 1.47-9.41; p < 0.01; >12 years: beta (β) 0.27; 95% CI: 2.51-12.67; p < 0.01). However, the multivariate model revealed that only social functioning (beta (β) 0.57; 95% CI: 0.27-0.53; p < 0.001) and education level (8-12 years: beta (β) 0.21; 95% CI: 1.10-8.260; p < 0.05; >12 years: beta (β) 0.21; 95% CI: 1.18-10.30; p < 0.05) were significantly associated with emotional well-being in KOA patients. Conclusions: The findings of this study indicate that a reduced social functioning and a lower educational attainment are linked to a poorer emotional well-being among patients with KOA.

The impact of obesity and overweight on response to internet-delivered cognitive behavioural therapy for adults with chronic health conditions

BACKGROUND

There is growing evidence that internet-delivered cognitive behavioural therapy (iCBT) can improve functioning and reduce psychological distress in people with chronic health conditions. Obesity frequently co-occurs with chronic health conditions, yet its impact on response to psychological interventions in this population is not known. The current study examined associations between BMI and clinical outcomes (depression, anxiety, disability, and satisfaction with life) following a transdiagnostic iCBT program targeting adjustment to chronic illness.

METHODS

Participants from a large randomised controlled trial, who provided information on height and weight, were included (N = 234; mean age= 48.32, SD = 13.80; mean BMI = 30.43, SD = 8.30, range 16.18-67.52; 86.8% female). The influence of baseline BMI range on treatment outcomes at post-treatment and 3-month follow-up was examined using generalized estimating equations. We also examined changes in BMI and in participants' perceived impact of weight on their health.

RESULTS

Improvement in all outcomes occurred across BMI ranges; additionally, persons with obesity or overweight generally experienced greater symptom reductions than those within a healthy weight range. A greater proportion of participants with obesity achieved clinically significant change on key outcomes (e.g., depression: 32% [95% CI: 25%, 39%]) than participants with a healthy weight (21% [95% CI: 15%, 26%]) or overweight (24% [95% CI: 18%, 29%], p = 0.016). There were no significant changes in BMI from pre-treatment to 3-month follow-up, however there were significant reductions on the self-rated impact of weight on health.

CONCLUSIONS

Persons with chronic health conditions and with obesity or overweight benefit at least as much as those with a healthy BMI from iCBT programs targeting psychological adjustment to chronic illness, even without changes in BMI. iCBT programs may be an important component in the self-management of this population, and may address barriers implicated in health behaviour change.

Researcher's Perspective on Musculoskeletal Conditions in Primary Care Physiotherapy Units through the International Classification of Functioning, Disability, and Health (ICF): A Scoping Review

(1) Background: Musculoskeletal disorders are the second cause of disability in the world. The International Classification of Functioning Disability and Health (ICF) is a tool for systematically describing functioning. Outcome measures for musculoskeletal disorders and functioning concepts embedded in them have not been described under the ICF paradigm. The objective of this scoping review was to identify ICF categories representing the researcher's perspective and to compare them with the ICF core set for post-acute musculoskeletal conditions. (2) Methods: This review was conducted as follows: (a) literature search using MEDLINE/PubMed, CINAHL, Web of Science, and Scopus databases; (b) study selection applying inclusion criteria (PICOS): musculoskeletal conditions in primary care, application of physiotherapy as a treatment, outcome measures related to functioning, and experimental or observational studies conducted in Western countries during the last 10 years; (c) extraction of relevant concepts; (d) linkage to the ICF; (e) frequency analysis; and (f) comparison with the ICF core set. (3) Results: From 540 studies identified, a total of 51 were included, and 108 outcome measures were extracted. In the ICF linking process, 147 ICF categories were identified. Analysis of data showed that 84.2% of the categories in the ICF core set for post-acute musculoskeletal conditions can be covered by the outcome measures analyzed. Sixty-eight relevant additional ICF categories were identified. (4) Conclusion: Outcome measures analyzed partially represent the ICF core set taken as a reference. The identification of additional categories calls into question the applicability of this core set in primary care physiotherapy units.

The quality of physiotherapy and rehabilitation program and the effect of telerehabilitation on patients with knee osteoarthritis

OBJECTIVE

To compare the effects of telerehabilitation vs home-based exercise programs for knee osteoarthritis (KOA).

METHOD

Patients diagnosed with moderate/mild KOA were enrolled in the study and randomized into two groups. The patients in the telerehabilitation group did their exercises via video conference simultaneously, accompanied by a physiotherapist, while the patients in the control group were given a brochure showing how to do the exercises and explaining how to do each exercise. Patients completed 30-s chair stand test (30 CST), Knee Injury and Osteoarthritis Outcome Score (KOOS), Numeric Rating Scale (NRS), International Physical Activity Questionnaire Short Form (IPAQ-SF), Hospital Anxiety and Depression Scale (HADS), TAMPA Kinesiophobia Scale (TKS), Fatigue Severity Scale (FSS) twice before and after 8-week treatment, and Quality Indicators Questionnaire for Physiotherapy Management of Hip and Knee Osteoarthritis (QUIPA) and Exercise Adherence Rating Scale (EARS) after treatment only. Moreover, the number of painkillers that patients used in the last 15 days was recorded before and after treatment, and patient satisfaction with treatment was questioned after treatment.

RESULTS

Forty-eight patients were included in the study. The mean age of patients was 55.83 ± 6.93 years, and 43 (89.6%) patients were women. No significant differences were determined between groups in terms of baseline characteristics. After the 8-week follow-up, telerehabilitation group demonstrated better 30 CST, IPAQ-SF, KOOS, QUIPA, treatment satisfaction, and total and C subscale of EARS scores increment and greater NRS, HADS, TKS, and FSS score reduction than the control group. It was determined that there was a statistically significant difference between the telerehabilitation and control groups for all of the specified parameters; however, no statistically significant difference was found for the B subscale of EARS.

CONCLUSION

This study indicated that telerehabilitation is superior to self-management. Moreover, through this innovative and population specific web-based approach for KOA, a vast number of patients who have internet access could be reached. Thus, patients with KOA received effective treatment.

Targeted exercises can improve biomechanical markers in individuals with knee osteoarthritis: A secondary analysis from a cluster randomized controlled trial

BACKGROUND

It is not clear whether exercise therapy significantly improves knee biomechanics during gait in osteoarthritis (OA) patients. This study aimed to determine whether targeted exercises based on a knee kinesiography exam improve biomechanical markers (BMs) compared with conventional primary care (CPC) management.

METHODS

This was a secondary analysis of a cluster randomized controlled trial in which patients were assigned to one of three groups: (1) Control (CPC), (2) Exercise, and (3) Exercise&Education. Fourteen known BMs in knee OA patients were assessed. The primary outcome was the global evolution ratio (GER), which was calculated as the sum of improved BMs over the sum of deteriorated BMs 6 months after baseline assessment. GER scores were categorized with three different sets of cut-off values into clinical levels: (a) Deteriorated, (b) Stabilized, and (c) Improved. Ordinal logistic regressions were performed on the per-protocol population to determine whether there was a relationship between group assignment and GER levels.

RESULTS

Of the 221 eligible participants, 163 were included. Two different regression models showed that patients from Group 3 (Exercise&Education) were 2.5-times more likely to be in an upper GER level (i.e., Stabilized or Improved) than patients from the control group (both odds ratio (OR) > 2.46, Wald Χ²(1) ≥ 7.268, P ≤ 0.01). They also reported significantly more improvement in pain and function (Knee Injury and Osteoarthritis Outcome Score, both P ≤ 0.01).

CONCLUSIONS

Results suggest that targeted exercises can improve biomechanical markers in knee OA patients compared with CPC treatment. Further studies are needed to confirm these findings and refine the biomechanical markers to address to maximize patients' clinical outcomes.

Depression in Osteoarthritis: Current Understanding

Depression, one of the most common comorbidities with osteoarthritis (OA), affects patient prognosis and quality of life. It also increases the overall burden of disease. This subgroup of patients has not been effectively managed in clinical settings. The study aimed to direct physicians' attention to the co-occurrence of depression and OA. Therefore, this review summarizes the relevant literature published over the past 10 years. The focus is on the prevalence of and risk factors for depression in OA, the effects of depression on OA development and treatment response, comorbidity mechanisms, screening, and non-pharmacological treatment. The research on the etiology of depression has been driven largely by epidemiological studies. Recent studies have shown that high levels of pain, poor levels of function, high numbers of OA sites, and slow gait might be associated with depression. However, the pathophysiology of OA and depression comorbidities remains unclear. In addition to immune inflammation and structural changes in the brain, which have been documented in brain imaging studies, psychosocial factors may also play a role. The evidence indicates that depression can be treated with early intervention; however, adjustments may need to be made for individuals with comorbid depression in OA. It is recommended that health care providers pay more attention to depressive symptoms in patients with OA. Clinicians should develop and implement an individualized and comprehensive treatment plan for patients based on a mental health assessment and in teams with other professionals to optimize treatment outcomes.

Moderators of the Effect of a Self-directed Digitally Delivered Exercise Program for People With Knee Osteoarthritis: Exploratory Analysis of a Randomized Controlled Trial

BACKGROUND

A 24-week self-directed digitally delivered intervention was found to improve pain and function in people with knee osteoarthritis (OA). However, it is possible that this intervention may be better suited to certain subgroups of people with knee OA compared to others.

OBJECTIVE

The aim of this study was to explore whether certain individual baseline characteristics moderate the effects of a self-directed digitally delivered intervention on changes in pain and function over 24 weeks in people with knee OA.

METHODS

An exploratory analysis was conducted on data from a randomized controlled trial involving 206 people with a clinical diagnosis of knee OA. This trial compared a self-directed digitally delivered intervention comprising of web-based education, exercise, and physical activity program supported by automated exercise behavior change mobile phone text messages to web-based education alone (control). The primary outcomes were changes in overall knee pain (assessed on an 11-point numerical rating scale) and physical function (assessed using the Western Ontario and McMaster Universities Osteoarthritis Index function subscale [WOMAC]) at 24 weeks. Five baseline patient characteristics were selected as the potential moderators: (1) number of comorbidities, (2) number of other painful joints, (3) pain self-efficacy, (4) exercise self-efficacy, and (5) self-perceived importance of exercise. Separate linear regression models for each primary outcome and each potential moderator were fit, including treatment group, moderator, and interaction between treatment group and moderator, adjusting for the outcome at baseline.

RESULTS

There was evidence that pain self-efficacy moderated the effect of the intervention on physical function compared to the control at 24 weeks (interaction P=.02). Posthoc assessment of the mean change in WOMAC function by treatment arm showed that each 1-unit increase in baseline pain self-efficacy was associated with a 1.52 (95% CI 0.27 to 2.78) unit improvement in the control group. In contrast, a reduction of 0.62 (95% CI -1.93 to 0.68) units was observed in the intervention group with each unit increase in pain self-efficacy. There was only weak evidence that pain self-efficacy moderated the effect of the intervention on pain and that number of comorbidities, number of other painful joints, exercise self-efficacy, or exercise importance moderated the effect of the intervention on pain or function.

CONCLUSIONS

With the exception of pain self-efficacy, which moderated changes in function but not pain, we found limited evidence that our selected baseline patient characteristics moderated intervention outcomes. This indicates that people with a range of baseline characteristics respond similarly to the unsupervised digitally delivered exercise intervention. As these findings are exploratory in nature, they require confirmation in future studies.

Prognostic Factors for Health Outcomes After Exercise Therapy and Education in Individuals With Knee and Hip Osteoarthritis With or Without Comorbidities: A Study of 37,576 Patients Treated in Primary Care

OBJECTIVE

To identify prognostic factors for health outcomes following an 8-week supervised exercise therapy and education program for individuals with knee and hip osteoarthritis (OA) alone or with concomitant hypertension, heart or respiratory disease, diabetes mellitus, or depression.

METHODS

We included individuals with knee and/or hip OA from the Good Life With OsteoArthritis in Denmark (GLA:D) program. GLA:D consists of 2 patient education sessions and 12 supervised exercise therapy sessions. Before GLA:D, participants self-reported any comorbidities and were categorized into 8 comorbidity groups. Twenty-one potential prognostic factors (demographic information, clinical data, and performance-based physical function) gathered from participants and clinicians before the program were included. Outcomes were physical function using the 40-meter Fast-Paced Walk Test (FPWT), health-related quality of life using the 5-level EuroQol 5-domain (EQ-5D-5L) index score, and pain intensity using a visual analog scale (VAS; range 0-100) assessed before and immediately after the GLA:D program. Within each comorbidity group, associations of prognostic factors with outcomes were estimated using multivariable linear regression.

RESULTS

Data from 35,496 (40-meter FPWT) and 37,576 (EQ-5D-5L and VAS) participants were included in the analyses. Clinically relevant associations were demonstrated between age, self-efficacy, self-rated health, and pain intensity and change in 40-meter FPWT, EQ-5D-5L, or VAS scores across comorbidity groups. Furthermore, anxiety, education, physical function, and smoking were associated with outcomes among subgroups having depression or diabetes mellitus in addition to OA.

CONCLUSION

Age, self-efficacy, self-rated health, and pain intensity may be prognostic of change in health outcomes following an 8-week exercise therapy and patient education program for individuals with OA, irrespective of comorbidities.

Associations between comorbidities and immediate and one-year outcomes following supervised exercise therapy and patient education - A cohort study of 24,513 individuals with knee or hip osteoarthritis

OBJECTIVE

To investigate if comorbidities are associated with change in health outcomes following an 8-week exercise and education program in knee and hip osteoarthritis (OA).

METHODS

We included 24,513 individuals with knee or hip OA from the Good Life with osteoArthritis in Denmark (GLA:D®). GLA:D® consists of two patient education sessions and 12 supervised exercise sessions. Before the program, individuals self-reported having one or more of 11 common comorbidities. Physical function was assessed using the 40-m Fast-Paced Walk Test (FPWT, m/sec) before and immediately after the program. Pain intensity and health-related quality of life was self-reported before, immediately after, and at 12 months post-intervention using a visual analogue scale (VAS, 0-100) and the EQ-5D-5L index (-0.624 to 1.000), respectively. Associations of comorbidity combinations with change in outcomes immediately and at 12 months was estimated using mixed linear regression.

RESULTS

Individuals with OA improved on average 0.12 m/s (95%CI 0.12 to 0.13) in 40-m FPWT, -12.7 mm (95%CI -13.2 to -12.2) in VAS, and 0.039 (95%CI 0.036 to 0.041) in EQ-5D-5L from before to immediately after the intervention with minor additional improvements at 12 months. Despite that individuals with comorbidities had worse baseline scores in all outcomes than individuals without comorbidities, they had similar levels of improvement immediately and 12 months after the intervention.

CONCLUSION

Comorbidities are not associated with worse nor better health outcomes following an 8-week exercise and education program in individuals with OA, suggesting exercise as a viable treatment option for individuals with OA, irrespective of comorbidities.

Challenges with strengthening exercises for people with knee osteoarthritis and comorbid obesity: a qualitative study with patients and physiotherapists

OBJECTIVE

Explore challenges associated with implementing a home-based strengthening exercise program for people with knee osteoarthritis and comorbid obesity.

METHODS

Qualitative study embedded within a randomised controlled trial comparing two home-based strengthening programs (weight bearing functional exercise versus non-weight bearing quadriceps strengthening exercise) for people with knee osteoarthritis and comorbid obesity. Patients in both exercise programs attended five consultations with a physiotherapist and undertook a home-based exercise program for 12 weeks. Semi-structured individual telephone interviews were conducted with 22 patients after trial completion, and all seven physiotherapists who delivered trial interventions. Interviews were recorded, transcribed verbatim, and thematically analysed using an inductive approach.

RESULTS

Three themes arose: i) psychological challenges (false assumptions about exercise; fear of pain; disliking exercise; mental effort of weight bearing functional program; underestimating capability) ii) physical challenges (complexity of weight bearing functional program; cuff weights and straight leg raise problematic in non-weight bearing quadriceps program; other health conditions), and; iii) overcoming challenges (incentives to exercise; accountability; education and reassurance; tailoring the exercise program).

CONCLUSION

Patients and physiotherapists experienced numerous psychological and physical challenges to exercise, including a fear of pain, having false assumptions about exercise, difficulties with exercise performance, application of cuff weights, and adverse impacts of other health conditions.

Anxiety and Osteoarthritis Disability: Updated Overview and Commentary

Introduction:

Osteoarthritis, a widespread highly painful often incapacitating joint disease continues to impose immense personal and societal challenges among adults of all ages, especially among older adults. In the absence of any effective cure or treatment, it has become essential to explore all correlates of this chronic disabling disease, especially those that might be preventable or modifiable. Anxiety, a potentially remediable state of mental distress - found linked to chronically disabling forms of arthritis, in various imperceptible ways, and which may have an immense bearing on the outcomes of osteoarthritis, has not received as much attention in the related literature as other topics, such as surgery.

Objective:

In line with previous promising work, this narrative review elected to explore the extent to which current researchers in the field are pursuing this topic, and if so, the degree to which prevailing peer-reviewed data sources support an important role for continued research in this realm, and in what regard.

Methods:

Primarily explored were the key databases housing relevant publications that emerged over Aug 1, 2018-Feb 26, 2020 using the keywords Osteoarthritis and Anxiety. Using a descriptive approach, the relative progress made over the past five previous years in this regard was assessed, in addition to what joints have been studied and with what frequency, and how the degree of interest compares to other currently researched osteoarthritis themes. The potential for intervening in the osteoarthritis pain cycle by addressing anxiety was also examined.

Results:

Findings show a high level of current interest in this topic, and that despite the paucity of prospective studies, studies on joints other than the knee and hip joints, some equivocal conclusions, small numbers of anxiety-related studies compared to other topics, and substantive design limitations, it appears that future research in this realm is strongly indicated.

Conclusion:

This topic if examined further is likely to produce highly advantageous results at all stages of the osteoarthritic disease process and in the context of primary, secondary, as well as tertiary measures to ameliorate osteoarthritis pain and disability.

Wireless Motion Sensors-Useful in Assessing the Effectiveness of Physiotherapeutic Methods Used in Patients with Knee Osteoarthritis-Preliminary Report

Osteoarthritis of the knee (OAK) is characterized by pain, limitation of joint mobility, and significant deterioration of proprioception resulting in functional decline. This study assessed proprioception in OAK patients following two ten-day rehabilitation programs using the Orthyo® system. Fifty-four study participants with clinical symptoms and radiological signs of OAK were randomly divided into an exercise group (n = 27) or a manual therapy group (n = 27). The control group consisted of 27 volunteers with radiological signs of OAK, but with no clinical symptoms or prior history of rehabilitation. The following parameters were assessed: knee proprioception using inertial sensors and a mobile application, patients' function using Western Ontario and McMaster Universities osteoarthritis index (WOMAC), and pain intensity using the visual analog scale (VAS). Following rehabilitation, knee proprioception tests did not improve in either study group. Both study groups showed significant improvement of the WOMAC-assessed function (exercise group: p < 0.01, manual therapy group: p = 0.01) and a significant decrease (p < 0.01) of VAS-assessed pain following rehabilitation, but the post-therapy results did not differ significantly between the aforementioned groups. The Orthyo® system provided a quick and accurate assessment of the knee joint position sense. There was no direct relationship between functionality, pain, and proprioception threshold in the knee joint.