Orthotic design from the New England Regional Spinal Cord Injury Center. Suggestion from the field.

Long-leg bracing affords ambulatory potential and helps reduce the incidence of deformity in patients with paralysis or weakness caused by lesions of the spinal cord. The conventional long-leg brace or knee-ankle orthosis (KAO) consists of double metal uprights, drop locks or bail locks at the knee, double action ankle joints with anterior and posterior pin stops, metal stirrup, and steel shank extending to the metatarsal heads. Uprights are fastened to the leg with various combinations of thigh and shank bands. In the Craig-Scott Orthosis (CSO), Scott refined this design by minimizing the number of leg bands so that threepoint knee stabilization comes from a rigid anterior closure below the knee coupled with a thigh band superiorly and a heel counter inferiorly. In addition, the knee joints are displaced 0.75 to 0.73 in* posterior to the transverse axis of the knee and behind the weightbearing line. This position creates an extension moment that enhances stability while easing pressure on the locking mechanism and on the skin under the pretibial restraint. In 1981, we at the New England Regional Spinal Cord Injury Center (NERSCIC) sought to develop a KAO that incorporated the superior features of the CSO but eliminated the need for heavy, custom-made shoes and mechanical ankle joints. Our intent was to devise a durable, light-weight orthosis that would be cosmetically acceptable to the wearer and would cost less than currently available KAOs. To this end, we combined double metal uprights with a molded plastic ankle-foot orthosis (MAFO) (Fig. 1). The components of the NERSCIC orthosis consist of ankle-foot support from a MAFO .25-in thick, stress-relieved polypropylene, vacuum molded to a positive cast. The ankle can be fixed in a prescribed degree of plantar flexion or dorsiflexion; however, we have found the neutral to 5 degrees of dorsiflexion position quite satisfactory for ambulation. Medial and lateral aluminum uprights (0.73 x 0.25 in) are triple riveted to the MAFO. To increase knee stability, stainless steel drop lock knee joints are offset 0.75 in posteriorly. The medial upright ends 1.5 to 2 in below the greater trochanteric terminum of the lateral post. A proximal thigh band slants medially to avoid contact with the ishium. The band includes a padded solid aluminum posterior segment and a leather anterior thigh cuff with Velcro closure belt. An aluminum cuff across the tibial flare completes the three-point support system. Tibial pressure relief is provided by .50-in high density, foam padding. Laterally, two Jewett back brace snaps hold the cuff in place (Fig. 2).