Is valgus unloader bracing effective in normally aligned individuals: implications for post-surgical protocols following cartilage restoration procedures.
OBJECTIVE
Utilizing valgus unloader braces to reduce medial compartment loading in patients undergoing cartilage restoration procedures may be an alternative to non-weightbearing post-operative protocols in these patients. It was hypothesized that valgus unloader braces will reduce knee adduction moment during the stance phase in healthy subjects with normal knee alignment.


METHODS
Gait analysis was performed on twelve adult subjects with normal knee alignment and no history of knee pathology. Subjects were fitted with an off-the-shelf adjustable valgus unloader brace and tested under five conditions: one with no brace and four with increasing valgus force applied by the brace. Frontal and sagittal plane knee angles and external moments were calculated during stance via inverse dynamics. Analyses of variance were used to assess the effect of the brace conditions on frontal and sagittal plane joint angles and moments.


RESULTS
With increasing tension in the brace, peak frontal plane knee angle during stance shifted from 1.6° ± 4.2° varus without the brace to 4.1° ± 3.6° valgus with maximum brace tension (P = 0.02 compared with the no brace condition). Peak knee adduction moment and knee adduction impulse decreased with increasing brace tension (main effect of brace, P < 0.001). Gait velocity and sagittal plane knee biomechanics were minimally affected.


CONCLUSIONS
The use of these braces following a cartilage restoration procedure may provide adequate protection of the repair site without limiting the patient's mobility.
Nicholas Institute of Sports Medicine and Athletic Trauma, 100 E. 77th St., 2nd Floor, New York, NY, 10075, USA, karl@nismat.org.
Karl F
KF
Orishimo
Ian J
IJ
Kremenic
Steven J
SJ
Lee
Malachy P
MP
McHugh
Stephen J
SJ
Nicholas
D000328:Adult; D001696:Biomechanical Phenomena; D001915:Braces; D002358:Cartilage, Articular / Q000502:physiology* / Q000601:surgery; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology* / Q000601:surgery; D008297:Male; D016474:Weight-Bearing / Q000502:physiology*