Design Evaluation in Novel Orthoses for Patients with Medial Knee Osteoarthritis

Orthosis Management in Knee Osteoarthritis: Evaluating Existing Recommendations and Achieving Consensus on Implementation Through the Delphi Method

OBJECTIVE

The available evidence on orthosis management in the knee osteoarthritis (KOA) remains questionable. This study aims to evaluate existing recommendations and achieve consensus on their implementation through the modified Delphi method.

METHODS

Experienced experts in orthosis management for KOA patients participated in three Delphi rounds. Each round involved addressing various questions related to recommended orthosis type such as insole, knee brace, footwear, indications and contraindications, dosage of orthosis usage, follow-up period, long-term side effects, fitting, and weaning procedure. Consensus was defined as  ≥ 70% agreement with a question.

RESULTS

Consensus was achieved for all questions. Experts frequently recommended custom-made insoles, neoprene knee braces, and appropriate footwear. The recommended duration of insole and knee brace usage averaged 3-6 months. Insole usage was advised during all weight-bearing activities, while knee braces were suggested for 4-6 h per day. Experts recommended orthosis follow-up for an average of 4-6 months. Reduced compliance with orthoses was highlighted by experts as the most significant long-term side effect. The fitting of orthoses is typically evaluated through gait analyses, assessment of symptoms and comfort, and observation of the corrective effects on impaired biomechanics in the clinical setting. Besides, experts commonly recommend a gradual weaning process from orthoses.

CONCLUSIONS

This study addresses the existing lack of consensus on orthosis management in KOA and provides essential clinical practice recommendations from multidisciplinary experts.

Design and evaluation of a wedge-shaped adaptive knee orthosis for the human lower limbs

Introduction

The incidence of knee osteoarthritis (KOA) is moderately correlated with age and body weight and increases with life span and weight gain, associated with tearing and wearing the knee joints. KOA can adjust the force through the human lower limbs, redistribute the load of the knee joint, reduce the pain, and restore mobility when the arthritis changes are mild. However, most of the existing knee orthosis cannot be adjusted adaptively according to the needs of patients.

Methodology

This study establishes a biomechanical model of the knee joint to analyze the medial and lateral forces acting on the joint. The new adjustable knee orthosis is designed. It applies the principle of four-point bending to apply pressure to both sides of the knee joint, thereby adjusting the varus angle and modifying the medial and lateral forces on the knee joint. Through structural optimization, the prototype of the knee orthosis weighs only 324 g. Utilizing three-dimensional scanning technology, discrete point cloud data of the leg surface is obtained, reconstructed, and processed to create a 3D model of the human leg surface. The design ensures a close fit to the human leg surface, offering comfortable wear. A pressure sensing film system is employed to build a pressure sensing test system, where the knee orthosis is worn on a prosthesis for pressure testing to evaluate its ability to adjust knee joint forces.

Results

The pressure test results demonstrate that the knee orthosis can stably provide an adjustment angle of 0-7° and sustain a maximum force of 10N on both sides of the knee joint over extended periods. A self-developed 8-channel plantar pressure sensing insole is calibrated against commercial plantar pressure sensors. Human wear tests on 15 subjects show that during the operation of the knee orthosis, it significantly adjusts plantar pressures, reducing lateral foot pressures by 22% overall, with more pronounced corrective effects observed in lighter participants.

Discussion

In this study, a wedge-shaped adaptive knee orthosis was provided for KOA patients. The four-point force principle was used to balance the force between femurs and tibia and adjust the meniscus contact gap. The orthotic appliance has the advantages of simple mechanical structure, adjustable correction Angle and good wearing comfort.

Study on the Influencing Factors of Osteoarthritis in Southern China

Background

Osteoarthritis (OA) is a common chronic disease with numerous and interacting influencing factors, and current inadequate patient perceptions and behaviors in access to care contribute to the difficulties in the diagnosis, treatment, and management of osteoarthritis.

Objective

The purpose of this study was to investigate the influencing factors of osteoarthritis (OA) in a southern Chinese population and to provide a scientific basis for the prevention and treatment of OA.

Methods

A 1 : 2 matched case-control study was used to select 160 patients with OA from three hospitals in southern China as a case group. Three hundred and twenty cases of the same sex and similar age (within ± 2 years) were selected as the control group, and relevant data were collected for univariate and multivariate conditional logistic regression analysis.

Results

There were no significant differences between the two groups of participants in terms of age, sex, and education (P > 0.05). Logistic regression statistical analysis showed that genetic factors (OR = 4.52, 95% CI = 1.56-7.83), body mass index (OR = 2.57, 95% CI = 1.16-5.84), alcohol consumption (OR = 3.81, 95% CI = 1.53-5.87), and a history of external joint limb injury (OR = 3.37, 95% CI = 1.67-5.24) would increase the risk of OA. In contrast, eating more fresh vegetables (OR = 0.08, 95% CI = 0.03-0.31), more fresh fruits (OR = 0.34, 95% CI = 0.12-0.96), more soy products (OR = 0.11, 95% CI = 0.04-0.45), and exposure to sunlight (OR = 0.31, 95% CI = 0.14-0.71) would reduce the OA risk of OA.

Conclusion

Obesity, alcohol consumption, and a history of joint trauma all increase the risk of OA in a southern Chinese population, whereas a diet rich in fresh vegetables, fresh fruit, soy products, and sun exposure would reduce the risk of OA. In the future, we should focus on improving patients' awareness of medical care and developing their self-management skills, improving GPs' treatment skills, improving negative attitudes of both doctors and patients, and promoting positive patient care.

Biomechanical Effect of Valgus Knee Braces on the Treatment of Medial Gonarthrosis: A Systematic Review

Background

Valgus braces are prescribed as a common conservative treatment option for patients with medial gonarthrosis to improve their quality of life. Many studies had reviewed the effects of the valgus braces on patients with medial gonarthrosis, while they mainly focused on the knee adduction moment (KAM), with less attention paid to other parameters such as spatiotemporal and morphological parameters.

Objectives

The purpose of this study was to review the effects of valgus braces on the spatiotemporal, kinematic/kinetic, morphological, and muscle parameters.

Methods

Based on the selected keywords, a survey of literatures was performed in Web of Science, PubMed, Scopus, and Google Scholar using the PRISMA methods, and the search period was established from January 2000 to March 2022.

Results

Thirty-four articles were included. According to the conclusion of these articles, the valgus brace can be used to relieve the symptoms of patients with medial gonarthrosis by decreasing the varus angle, decreasing the KAM, and redistributing the knee compartment loads. However, the effects of valgus braces on other biomechanical parameters (e.g., walking speed, cadence, joint angle, and joint space) had not reached a consensus.

Conclusions

The valgus knee brace can effectively relieve the symptoms of medial gonarthrosis through multiple mechanisms, while there is still some confusion about the effectiveness of the valgus brace on the other biomechanical parameters.