Conservación de las relaciones familiares frente a la separación

It is possible that the previously mentioned symptoms of knee OA (pain, decreased

function, increased knee adduction moment, increased medial joint loads, increased

impulsive loading and muscle co-contraction, and decreased knee flexion at contact) may be

ameliorated through an improvement in proprioception. Several studies have demonstrated

that proprioception can be enhanced from the use of knee sleeves, braces, and bandages in

both normal subjects and those with knee OA [29, 51-53]. But these improvements are seen

in non weightbearing (NWB) situations [51, 52] rather than during closed kinetic chain

exercises, which may be because there is more proprioceptive input available in a

weightbearing situation, thus minimizing any improvement by a knee sleeve. There are

several types of knee braces and sleeves that have been investigated as a means of alleviating

pain and improving function in knee OA [53-56]. They include elastic bandages, neoprene

sleeves, hinged knee braces, and medial unloader braces. These knee braces and sleeves

have also been investigated as a means of improving balance, proprioception, medial joint

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loading, and mechanical stability in normal subjects [51, 57, 58] and in those with knee OA

[52, 53, 55, 59, 60]. Hassan et al. found that pain, proprioceptive acuity, and static postural

sway were all improved while wearing an elastic bandage in subjects with knee OA [53].

They speculated the main reason for these improvements was due to stimulation of cutaneous

mechanoreceptors since it is currently thought that knee braces and sleeves effectively

provide an added sensation of stability, rather than any biomechanical reinforcement itself.

This enhanced sensation of stability may be related to the improvement in proprioceptive

acuity seen by Herrington et al. [58]. They tested the effect of a neoprene knee sleeve on

proprioceptive acuity of normal subjects and found a 28% improvement in the accuracy of an

active tracking task, which is another way to measure proprioception.

Medial unloader braces have been looked at as a method for improving the symptoms

of knee OA, such as heightened medial compressive forces in the medial aspect of the knee

[61], pain [56], and functionality [62]. The main mechanism by which the medial unloader

brace works is by placing the knee in a more valgus position and as the subject bends his/her

knee the medial compartment of the knee is slightly unloaded, resulting in pain reduction and

improved function. One study specifically measured the separation of the femoral condyle

from the tibial plateau just after heel strike while wearing an unloader knee brace in patients

with medial knee OA [54]. Using video fluoroscopy under weight-bearing conditions, the

authors found medial condylar separation with corresponding pain relief in 78% of patients

they tested. Specific to symptomatic improvement in knee OA, Matsuno et al. looked at the

Generation II medial unloader knee brace and found that it improved pain during walking

and stair ascent and descent, the femorotibial angle decreased, and quadriceps strength

increased in 19 of the 20 patients tested [56]. Brouwer et al. also looked at the unloader

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brace and found that subjects exhibited overall longer walking distances while wearing a

brace compared to the control group [62]. However, Ramsey et al. demonstrated that neutral

aligning braces performed as well as or better than the valgus aligning brace in reducing pain,

disability, muscle co-contraction, and knee adduction excursions [55]. It is possible that the

decreased muscle co-contraction seen in this study may have been caused by enhanced

proprioception from simply wearing the knee brace. Additionally, several studies have

demonstrated the long-term effectiveness of knee braces and sleeves. Birmingham et al.

found that a neoprene knee sleeve was comparable to a functional knee brace after ACL

reconstruction with respect to disease specific quality of life when examined over the course

of several years [63]. Kirkley et al. found similar results in the disease specific quality of life

between a medial unloader brace and a neoprene knee sleeve after six months [60]. In

summary, research about the effects of braces for knee OA shows that wearing a knee brace

compared to not wearing a brace may increase walking distance, reduce pain, and improve

function and quality of life.

Another symptom of knee OA is increased external adduction moment, which causes

higher loads to be placed in the medial compartment of the tibio-femoral joint of the knee.

Foot orthotics such as lateral wedged insoles have been tested as a means of improving knee

mechanics, specifically reducing the increased knee adduction moments, in those with medial

compartment knee OA. Similar to knee braces and sleeves, the effectiveness of foot

orthotics, specifically lateral wedged insoles remains inconclusive. Crenshaw et al. found no

significant differences in hip, knee, or ankle joint angles or temporal or spatial parameters

when testing the effects of a lateral wedged insole in healthy subjects [64]. However, the

external varus moment and medial compartment loads were significantly reduced. The

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authors suggested that pain relief and improved function seen in patients with knee OA while

using lateral wedge insoles are likely the result of the reduced moment and compressive

loads. Shimada et al. also looked at the effects of lateral wedged insoles and found a

reduction in the peak external adduction moment of the knee in individuals with OA when a

insole was applied compared to a control group [65]. One important thing to note about this

study was that peak adduction moments were significantly improved in individuals with

Kellgren and Lawrence grades I and II OA, but not in those with grades III and IV. The

authors speculated this was because those with grades III and IV had severe varus

deformities as well as changes in center of pressure and moment arms, thus the insole would

not be sufficient to produce a measurable effect. A Cochrane review summarized the results

of three insole studies and concluded that when wearing a lateral wedge compared to a

neutral wedge, those with knee OA may not experience any difference in pain or knee

function [66]. This further demonstrates the inconclusive findings of studies investigating

the effect of lateral wedge insoles on the symptoms of knee OA.