Combined versus individual effects of a valgus knee brace and lateral wedge foot orthotic during stair use in patients with knee osteoarthritis

Knee braces and foot orthoses multimodal 3-month treatment of medial knee osteoarthritis in a randomised crossover trial

PURPOSE

Immediate biomechanical and functional benefits of knee braces and lateral wedge foot orthoses (FO) are often reported on patients with medial knee osteoarthritis. However, the effectiveness of their combined use in a longer-term orthotic treatment remains unclear. The aim was to evaluate pain, function, comfort and knee adduction moment (KAM) during the stance phase of gait with three modalities of orthotic treatment.

METHODS

Twenty-two patients with knee osteoarthritis were analysed in a randomised crossover trial including a knee brace with valgus and external rotation functions (VER), FO and their combined use (VER + FO). Western Ontario and McMaster Universities scale (WOMAC) and Knee injury and Osteoarthritis Outcome Scores and KAM during gait were obtained before and after each orthotic treatment of 3 months. Repeated measures analyses of variance contrasted the factors orthosis (VER, FO, VER + FO), treatment (pre and post) and wear (without and with) on pain, function, comfort and KAM.

RESULTS

An interaction between orthosis and treatment on the WOMAC pain (effect size [ES] = 0.17) and a main effect on the pain visual analogue score (ES = 0.24) indicated that VER and VER + FO were more alleviating than FO. The three modalities of orthotic treatment significantly improved functional scores (ES > 0.2) and reduced discomfort (ES = 0.25). A significant multivariate interaction between orthosis and wear (ES = 0.73) showed that the KAM reduction while wearing the orthoses was more pronounced with the VER and VER + FO than the FO.

CONCLUSION

The VER-brace obtained more effectiveness than FO on pain and KAM after 3 months for medial knee osteoarthritis and the combined treatment did not substantially improve biomechanical and functional outcomes.

LEVEL OF EVIDENCE

Therapeutic study level I randomised crossover trial.

Estimation of Knee Assistive Moment in a Gait Cycle Using Knee Angle and Knee Angular Velocity through Machine Learning and Artificial Stiffness Control Strategy (MLASCS)

Nowadays, many people around the world cannot walk perfectly because of their knee problems. A knee-assistive device is one option to support walking for those with low or not enough knee muscle forces. Many research studies have created knee devices with control systems implementing different techniques and sensors. This study proposes an alternative version of the knee device control system without using too many actuators and sensors. It applies the machine learning and artificial stiffness control strategy (MLASCS) that uses one actuator combined with an encoder for estimating the amount of assistive support in a walking gait from the recorded gait data. The study recorded several gait data and analyzed knee moments, and then trained a k-nearest neighbor model using the knee angle and the angular velocity to classify a state in a gait cycle. This control strategy also implements instantaneous artificial stiffness (IAS), a control system that requires only knee angle in each state to determine the amount of supporting moment. After validating the model via simulation, the accuracy of the machine learning model is around 99.9% with the speed of 165 observers/s, and the walking effort is reduced by up to 60% in a single gait cycle.

Knee braces and foot orthoses multimodal treatment of medial knee osteoarthritis

BACKGROUND

Knee braces and lateral wedge foot orthoses are two treatment options recommended for medial knee osteoarthritis, but the combination of both of them could further improve their effectiveness.

RESEARCH QUESTION

The aim was to evaluate whether the combination of lateral wedge foot orthoses with two types of knee brace enhances the biomechanical effects and pain relief during the stance phase of gait while maintaining comfort.

METHODS

Ten patients with medial knee osteoarthritis were fitted with a standard valgus brace, an unloader brace with valgus and external rotation functions, and 7° lateral wedge foot orthoses. The pain relief, comfort, kinematics and kinetics of the lower limb were measured during walking without orthotics, with the combined and with the isolated treatments.

RESULTS

The valgus and external rotation brace significantly reduced the knee adduction moment and allowed more knee flexion both in isolation and in combination to foot orthoses compared to the valgus brace or without treatment. Pain relief was not significant with the different orthotic treatment modalities. The valgus brace and combined treatment with either brace significantly increased the discomfort level, whereas the valgus and external rotation brace or foot orthoses in isolation did not induce significant discomfort.

SIGNIFICANCE

Amongst the tested orthotic treatment modalities, the valgus and external rotation brace obtained better biomechanical outcomes while maintaining comfort. The combined treatment with foot orthoses enhanced the effectiveness of the valgus brace, however foot orthoses may be unnecessary with the valgus and external rotation brace.

Effects of foot orthoses on the biomechanics of the lower extremities in adults with and without musculoskeletal disorders during functional tasks: A systematic review

BACKGROUND

Foot orthoses are among the most commonly used external supports to treat musculoskeletal disorders. It remains unclear how they change the biomechanics of the lower extremities during functional tasks. This systematic review aimed to determine the effects of foot orthoses on primary outcomes (i.e., kinematics, kinetics and electromyography of the lower extremities) in adults with and without musculoskeletal disorders during functional tasks.

METHODS

A literature search was conducted for articles published from inception to June 2021 in Medline, CINAHL, SPORTDiscus, Cochrane libraries and PEDro electronic databases. Two investigators independently assessed the titles and abstracts of retrieved articles based on the inclusion criteria. Of the 5578 citations, 24 studies were included in the qualitative synthesis as they reported the effects of foot orthoses on the primary outcomes. Risk of bias of included studies was determined using the modified Downs and Black Quality Index.

FINDINGS

During low impact tasks, foot orthoses decrease ankle inversion and increase midfoot plantar forces and pressure. During higher impact tasks, foot orthoses had little effects on electromyography and kinematics of the lower extremities but decreased ankle inversion moments.

INTERPRETATION

Even though the effects of foot orthoses on the biomechanics of the lower extremities seem task-dependent, foot orthoses mainly affected the biomechanics of the distal segments during most tasks. However, few studies determined their effects on the biomechanics of the foot. It remains unclear to what extent foot orthoses features induce different biomechanical effects and if foot orthoses effects change for different populations.

Degenerative Meniscal Tears and High Tibial Osteotomy: Do Current Treatment Algorithms Need to Be Realigned?

Degenerative medial meniscal tears (DMMTs) are a common feature of early knee osteoarthritis (OA). Varus alignment is a strong risk factor for medial compartment knee OA and its progression. We propose that high tibial osteotomy (HTO) should be considered much earlier in the treatment algorithm for patients presenting with recurring medial knee pain, varus alignment, and DMMT, absent of radiographic OA. We provide rationale for investigating HTO as a disease-modifying intervention for secondary prevention in knee OA, and present case examples as low-level proof of principle. Finally, caveats and challenges are discussed along with proposed future research.

An Update on Unloading Knee Braces in the Treatment of Unicompartmental Knee Osteoarthritis from the Last 10 Years: A Literature Review

Background  The incidence of osteoarthritis is increasing and it is one of the most common causes of chronic conditions. Total knee replacement is the mainstay of treatment for end-stage knee osteoarthritis; however, with long waiting lists and high levels of dissatisfaction, a treatment like knee braces could potentially delay surgery. Unicompartmental knee osteoarthritis is associated with misalignment of the knee, and unloader bracing has been recommended by various guidelines to correct this misalignment. The aim of this report was to provide an update of evidence from the past 10 years on knee braces.

Methods  MEDLINE/EMBASE search was performed from the past 10 years.

Results  We reviewed the evidence from 14 published articles. Almost all articles supported knee brace use and showed it to decrease pain, improve function, and improve the quality of life of patients. One study in 2017 followed patients for long term and found knee bracing to be more cost effective than total knee replacement, and could replace the need for surgery. Several minor complications were reported with bracing, like soft tissue irritation, which could be due to poor fitting. A management strategy for this could be regular follow-up at a nurse-led clinic.

Conclusions  Unloader braces are an economical and effective treatment for unicompartmental knee osteoarthritis. They can significantly improve a patient's quality of life and potentially delay the need for surgery. Patients should be managed with a multidisciplinary approach with conservative management and knee bracing, before surgery is considered.

Effectiveness of Valgus Offloading Knee Braces in the Treatment of Medial Compartment Knee Osteoarthritis: A Systematic Review

CONTEXT:

Knee osteoarthritis affects 9.3 million adults over age 45 years in the United States. There is significant disability associated with this condition. Given the potential complications and the significant cost to the health care system with the dramatic increase in total knee arthroplasties performed for this condition, assessment of the efficacy of nonoperative modalities, such as offloading knee braces, is essential as part of optimizing nonoperative treatment for this condition.

OBJECTIVE:

To determine the effectiveness of valgus offloader braces in improving clinical outcomes for patients with medial compartment knee osteoarthritis.

DATA SOURCES:

Three databases (PubMed, MEDLINE, and EMBASE) were searched from database inception through July 28, 2017.

STUDY SELECTION:

Studies reporting outcomes of valgus offloader knee braces in the treatment of medial compartment knee osteoarthritis were included.

STUDY DESIGN:

Systematic review.

LEVEL OF EVIDENCE:

Level 4.

DATA EXTRACTION:

Data pertaining to demographics, descriptive statistics, and clinical outcomes were extracted from the included studies. The methodological quality of included studies was evaluated.

RESULTS:

A total of 31 studies were included, with a total of 619 patients. The majority of studies reported improved pain outcomes using valgus offloader braces. However, variable results were reported as to whether valgus offloader braces significantly improved functional outcomes and stiffness. Offloader bracing was more effective at reducing pain when compared with neutral braces or neoprene sleeves.

CONCLUSION:

Valgus offloader bracing is an effective treatment for improving pain secondary to medial compartment knee osteoarthritis. The literature remains unclear on the effectiveness of valgus offloader braces with regard to functional outcomes and stiffness. Larger prospective randomized trials with consistent outcome assessment tools and consideration of patient compliance would be beneficial to more accurately determine treatment effects of valgus offloader bracing.

Effect of foot progression angle adjustment on the knee adduction moment and knee joint contact force in runners with and without knee osteoarthritis

BACKGROUND

Knee adduction moment (KAM) is often used as a surrogate marker of knee contact force (KCF) during walking. Previous studies have reported potential benefits to reduce KAM in patients with knee osteoarthritis (OA) by foot progression angle adjustment. However, KAM is an external moment and it does not consider any muscle contribution to the joint loading, which should pose a greater influence in running than walking.

RESEARCH QUESTION

This study used a computational model to compare KAM and KCF between runners with and without knee OA during running. In addition, we evaluated the KAM and KCF when runners adjusted to an out-toe running style.

METHODS

Kinematic, kinetic, and lower limb EMG data were collected from 9 runners with knee OA and 10 healthy counterparts. They were asked to run at their usual speed with standard shoes on an instrumented treadmill.

RESULTS

We found no significant difference in the KAM during running between OA and the healthy group (p > 0.376). However, runners with knee OA exhibited a greater total KCF than the healthy counterparts (p < 0.041). We did not observe any reduction in KAM after foot progression angle adjustment (p > 0.346). Surprisingly, an increase in the longitudinal KCF and total KCF were found with adjustment of foot progression angle (p < 0.046).

SIGNIFICANCE

Unlike the findings reported by the previous walking trials, our findings do not support the notion that foot progression angle adjustment would lead to a lower joint loading during running.

Combining valgus knee brace and lateral foot wedges reduces external forces and moments in osteoarthritis patients

Osteoarthritis progression can be related to the external knee adduction and flexion moments during walking. Lateral foot wedges and knee braces have been used as treatment for osteoarthritis, but little is known about their influence on knee joint moments generated in the sagittal and frontal planes. Therefore, the aim of the present study was determine the effects of the isolated and combined use of valgus knee brace and lateral wedge foot orthotic on peak forces and moments during gait in knee osteoarthritis patients. Twenty four males (age: 62.1±2.0years) with varus alignment, symptomatic medial compartment knee osteoarthritis participated in this study. Subjects walked over ground at preferred speed in four conditions: (1) no assistive device (control); (2) using lateral wedges, (3) using knee braces, and (4) using both lateral wedges and knee braces. Ground reaction forces (GRF) and moments, as well as lower limb kinematics were recorded. Peak GRF, vertical loading rate, free moment, external knee adduction and flexion moments were compared across conditions. The concurrent use of lateral wedge and knee brace reduced the first peak GRF in the vertical (6%, p=0.002), anterior-posterior (30%, p=0.028) and medial-lateral directions (44%, p=0.029). Moreover, the use of these devices reduced the peak external knee adduction moment (25%, p=0.019), but not the external flexion moment and free moment (p>0.05). The combined use of lateral wedges and knee braces can reduce medial-lateral knee joint loading, but despite reduced peak forces in the sagittal plane, these device do not reduce joint moments.