The immediate effect of lateral wedge insoles, with and without a subtalar strap, on the lateral trunk lean motion in patients with knee osteoarthritis

Comparing Two Orthoses for Managing Medial Knee Osteoarthritis: Lateral Wedge with Subtalar Strap While Barefoot Versus Lateral Wedged Insole Fitted Within Sandal

BACKGROUND

Using foot orthoses for managing medial knee osteoarthritis (MKOA) is common, although its effectiveness is in debate. Most orthoses are placed inside the shoe as a lateral wedged insole. Thus, most studies in this area have focused on the effect of insoles used with shoes. This study compared the effects of a lateral wedge with subtalar strap (combined insole) used while barefoot and lateral wedged insole fitted within sandal on pain, function and external knee adduction moment (EKAM) in patients with MKOA to consider which orthotic treatment is better.

METHODS

In this quasi-experimental pretest-posttest study, 29 participants with medial knee osteoarthritis were divided into two groups: (1) combined insole (n = 15) and (2) sandal (n = 14) groups. We recorded their gait while walking with and without orthoses using a motion analysis system. We evaluated their pain and performance with visual analog scale, Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire, 30 s chair stand, and Timed Up and Go functional tests. The pain and performance evaluations were repeated after one month.

RESULTS

The pain immediately decreased after walking with both orthoses (p < 0.001). There was no significant difference in EKAM results between the two orthoses. Pain and performance improved in both groups after a one month using the orthoses (p < 0.01).

CONCLUSION

Both types of orthoses have similar effect and lead to better performance and less pain after 1 month.

The effect of a lateral wedge insole and a subtalar strap on gait parameters in knee osteoarthritis

Background: Lateral wedge insole (LWI) aims to reduce loading on medial compartment of tibiofemoral joint in mild knee osteoarthritis (KOA). This effect may be augmented by concomitant use of subtalar strap to fix the ankle joint. Moreover, longitudinal arch support embedded in insoles can cause foot comfort and may be beneficial for people with KOA. Therefore, this study aimed to assess the immediate effect of LWI with an arch support with and without a subtalar strap on the kinetics and kinematics of walking in mild KOA.

Methods: A convenient sample of 17 individuals with mild KOA (Kellgren and Lawrence grade II), aged ≥ 40 years were assessed in 3 conditions: without the insole; LWI; and LWI with a subtalar strap, where an arch support was embedded in all insoles. The primary outcomes were external knee adduction moment and angular impulse. The secondary outcomes were hip flexion and adduction moments, knee flexion angle, ankle eversion moment, and walking speed. The repeated measurements ANOVA was used to compare the primary and secondary outcomes between the conditions using SPSS. Significance level was set at 0.05.

Results: LWI and a subtalar strap can significantly increase the knee flexion angle at 0%-15% of the stance phase compared to no insole (p<0.001). No other changes were observed (p=0.142).

Conclusion: LWI with an arch, with or without a subtalar strap, cannot impose any immediate changes on the kinetics and kinematics of lower limb joints during walking in people with mild KOA.

Timing of Frontal Plane Trunk Lean, Not Magnitude, Mediates Frontal Plane Knee Joint Loading in Patients with Moderate Medial Knee Osteoarthritis

The purpose of this study was to examine the influence of trunk lean and contralateral hip abductor strength on the peak knee adduction moment (KAM) and rate of loading in persons with moderate medial knee osteoarthritis. Thirty-one males (17 with osteoarthritis, 14 controls) underwent 3-dimensional motion analysis, strength testing of hip abductors, and knee range of motion (ROM) measures, as well as completing the knee osteoarthritis outcome score (KOOS). No differences were found between groups or limbs for gait cycle duration, but the osteoarthritis group had longer double-limb support during weight acceptance (p < 0.001) and delayed frontal plane trunk motion towards the stance limb (p < 0.01). This was reflected by a lower rate of loading for the osteoarthritis group compared to controls (p < 0.001), whereas no differences were found for peak KAM. Trunk angle, contralateral hip abductor strength, and BMI explained the rate of loading at the involved knee (p < 0.001), an association not found for the contralateral knee or control knees. Prolonged trunk lean over the stance limb may help lower peak KAM values. Rate of frontal plane knee joint loading may partly be mediated by the contralateral limb's abductor strength, accentuating the importance of bilateral lower limb strength for persons with knee osteoarthritis.

The effects of shoe-worn insoles on gait biomechanics in people with knee osteoarthritis: a systematic review and meta-analysis

OBJECTIVES

The effect of shoe-worn insoles on biomechanical variables in people with medial knee osteoarthritis has been studied extensively. The majority of research has focused specifically on the effect of lateral wedge insoles at the knee. The aim of this systematic review and meta-analysis was to summarise the known effects of different shoe-worn insoles on all biomechanical variables during level walking in this patient population to date.

METHODS

Four electronic databases were searched to identify studies containing biomechanical data using shoe-worn insole devices in the knee osteoarthritis population. Methodological quality was assessed and a random effects meta-analysis was performed on biomechanical variables reported in three or more studies for each insole.

RESULTS

Twenty-seven studies of moderate-to-high methodological quality were included in this review. The primary findings were consistent reductions in the knee adduction moment with lateral wedge insoles, although increases in ankle eversion with these insoles were also found.

CONCLUSION

Lateral wedge insoles produce small reductions in knee adduction angles and external moments, and moderate increases in ankle eversion. The addition of an arch support to a lateral wedge minimises ankle eversion change, and also minimises adduction moment reductions. The paucity of available data on other insole types and other biomechanical outcomes presents an opportunity for future research.

Knee osteoarthritis: Clinical connections to articular cartilage structure and function

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