Unloader knee braces are prescribed for patients with unicompartmental osteoarthritis of the knee. These braces aim to reduce pain in patients by applying a coronal moment to the knee to unload the symptomatic knee compartment. However, existing unloading mechanisms use straps that go directly behind the knee joint, to apply the needed moment. This can impinge on the popliteal artery and peroneal nerves thereby causing discomfort to the patient. Hence, these braces cannot be worn for prolonged periods of time. This research focused on developing a new knee brace to improve comfort while unloading the osteoarthritic knee. A new knee brace was developed that uses a four-point bending approach to unload the knee. In this brace, unloading can be adjusted, and the unloading mechanism is away from the joint. The new brace was tested on a cadaver specimen to quantify its capability to unload the knee compartment. The brace was also worn by a patient with osteoarthritis who subjectively compared it to his existing unloader brace. During cadaver testing, the new brace design could reduce the force exerted on the medial condyle by 25%. Radiographic images of the patient's knee confirmed that the brace unloaded the medial condyle successfully. The patient reported that the new brace reduced pain, was significantly comfortable to wear and could be used for a longer duration in comparison to his existing brace.

References

1.
Felson
,
D. T.
,
Lawrence
,
R. C.
,
Dieppe
,
P. A.
,
Hirsch
,
R.
,
Helmick
,
C. G.
,
Jordan
,
J. M.
,
Kington
,
R. S.
,
Lane
,
N. E.
,
Nevitt
,
M. C.
,
Zhang
,
Y.
,
Sowers
,
M.
,
McAlindon
,
T.
,
Spector
,
T. D.
,
Poole
,
A. R.
,
Yanovski
,
S. Z.
,
Ateshian
,
G.
,
Sharma
,
L.
,
Buckwalter
,
J. A.
,
Brandt
,
K. D.
, and
Fries
,
J. F.
,
2000
, “
Osteoarthritis: New Insights. Part 1: The Disease and Its Risk Factors
,”
Ann. Intern. Med.
,
133
(
8
), pp.
635
646
.
2.
Shelburne
,
K. B.
,
Torry
,
M. R.
, and
Pandy
,
M. G.
,
2005
, “
Muscle, Ligament, and Joint-Contact Forces at the Knee During Walking
,”
Med. Sci. Sports Exercise
,
37
(
11
), pp.
1948
1956
.
3.
Kutzner
,
I.
,
Kuther
,
S.
,
Heinlein
,
B.
,
Dymke
,
J.
,
Bender
,
A.
,
Halder
,
A.
, and
Bergmann
,
G.
,
2011
, “
The Effect of Valgus Braces on Medial Compartment Load of the Knee Joint—In Vivo Load Measurements in Three Subjects
,”
J. Biomech.
,
44
(
7
), pp.
1354
1360
.
4.
Pollo
,
F. E.
,
Otis
,
J. C.
,
Backus
,
S. I.
,
Warren
,
R. F.
, and
Wickiewicz
,
T. L.
,
2002
, “
Reduction of Medial Compartment Loads With Valgus Bracing of the Osteoarthritic Knee
,”
Am. J. Sports Med.
,
30
(
3
), pp.
414
421
.
5.
Dennis
,
D. A.
,
Komistek
,
R. D.
,
Nadaud
,
M. C.
, and
Mahfouz
,
M.
,
2006
, “
Evaluation of Off-Loading Braces for Treatment of Unicompartmental Knee Arthrosis
,”
J. Arthroplasty
,
21
(
4
), pp.
2
8
.
6.
Finger
,
S.
, and
Paulos
,
L. E.
,
2002
, “
Clinical and Biomechanical Evaluation of the Unloading Brace
,”
J. Knee Surg.
,
15
(
3
), pp.
155
159
.
7.
Edwards
,
P. H.
,
Wright
,
M. L.
, and
Hartman
,
J. F.
,
2005
, “
A Practical Approach for the Differential Diagnosis of Chronic Leg Pain in the Athlete
,”
Am. J. Sports Med.
,
33
(
8
), pp.
1241
1249
.
8.
Englund
,
J.
,
2005
, “
Chronic Compartment Syndrome: Tips on Recognizing and Treating
,”
J. Fam. Pract.
,
54
(
11
), pp.
955
960
.
9.
McCrory
,
P.
,
Bell
,
S.
, and
Bradshaw
,
C.
,
2002
, “
Nerve Entrapments of the Lower Leg, Ankle and Foot in Sport
,”
Sport Med.
,
32
(
6
), pp.
371
391
.
10.
Squyer
,
E.
,
Stamper
,
D. L.
,
Hamilton
,
D. T.
,
Sabin
,
J. A.
, and
Leopold
,
S. S.
,
2013
, “
Unloader Knee Braces for Osteoarthritis: Do Patients Actually Wear Them?
,”
Clin. Orthop. Relat. Res.
,
471
(
6
), pp.
1982
1991
.
11.
Draganich
,
L.
,
Reider
,
B.
,
Rimington
,
T.
,
Piotrowski
,
G.
,
Mallik
,
K.
, and
Nasson
,
S.
,
2006
, “
The Effectiveness of Self-Adjustable Custom and Off-the-Shelf Bracing in the Treatment of Varus Gonarthrosis
,”
J. Bone Jt. Surg. Am.
,
88
(
12
), pp.
2645
2652
.
12.
Hangalur
,
G.
,
Brenneman
,
E.
,
Nicholls
,
M.
,
Bakker
,
R.
,
Laing
,
A.
, and
Chandrashekar
,
N.
,
2016
, “
Can a Knee Brace Reduce the Strain in the Anterior Cruciate Ligament? A Study Using Combined In Vivo/In Vivo Method
,”
Prosthet. Orthot. Int.
,
40
(
3
), pp.
349
399
.
13.
Cassidy
,
K.
,
Hangalur
,
G.
,
Sabharwal
,
P.
, and
Chadrashekar
,
N.
,
2013
, “
Combined In Vivo/In Vivo Method to Study Anteriomedial Bundle Strain in the Anterior Cruciate Ligament Using a Dynamic Knee Simulator
,”
ASME J. Biomech. Eng.
,
135
(
3
), p.
035001
.
14.
Ramsey
,
D. K.
,
Briem
,
K.
, and
Axe
,
M. J.
,
2007
, “
A Mechanical Hypothesis for the Effectiveness of Knee Bracing for Medial Compartment Knee Osteoarthritis
,”
J. Bone Jt. Surg. Am.
,
89
(
11
), pp.
2398
2407
.
15.
Birmingham
,
T. B.
,
Bryant
,
D. M.
,
Giffin
,
J. R.
,
Litchfield
,
R. B.
,
Kramer
,
J. F.
,
Donner
,
A.
, and
Fowler
,
P. J.
,
2008
, “
A Randomized Controlled Trial Comparing the Effectiveness of Functional Knee Brace and Neoprene Sleeve Use After Anterior Cruciate Ligament Reconstruction
,”
Am. J. Sports Med.
,
36
(
4
), pp.
648
655
.
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