Foot-loading patterns are one of the most direct measures of dynamic foot alignment during stance. By examining foot-loadingpatterns, clinicians can determine the sequence of contact points along the foot as weight is accepted. For example, a loadingpattern involving initial contact of the forefoot to the floor may give the clinician an objective indication of spasticity or ankle-joint range-of-motion limitations. This information would then better enable the clinician to make appropriate decisions aboutthe best course of treatment.Despite the usefulness of information about foot-loading patterns, the few published studies documenting neurologic patients'foot-loading patterns involve only the static examination of weightbearing when the foot is standing. In one such study it wasnoted that hemiplegic subjects bore significantly less weight through the involved leg, with less weight acceptance through theheel compared to age-matched normal control subjects (1). The foot-ground pressure pattern (FGP) used in this studymeasures the pattern of weightbearing when the subject is standing quietly; it does not give information about how the foot isloaded as the subject progresses through stance phase.Ryerson discusses three patterns of foot loading in hemiplegic subjects as the patient progresses through stance (2). Thesedifferent patterns are the result of the patient's level of muscle tone as well as the range of motion available at the talocruraland subtalar joints (3). While knowledge of these three patterns of foot loading is clinically useful, they have not beenexperimentally validated, and therapists working to alter these loading patterns do not have objective ways to measureimprovement.Further research in the area of foot-loading patterns in neurologic patients is needed. Currently, no studies document theeffect of various orthotic devices on these patients' foot-loading patterns. Data from such research may help validate theeffectiveness of commonly used orthotic management procedures used by clinicians in treating these patients.Tone-inhibiting orthoses are widely pre scribed in neurorehabilitation. One of thc most clinically popular tone-inhibitingorthoses is the dynamic ankle-foot orthosis (DAFO), a "very thin, flexible supramalleolar orthosis with a custom-contouredsole-plate to include support and stabilization to the dynamic arches of the foot" (4). The DAFO was designed based on theconcept that the most important aspect of tone-inhibiting orthotics is obtaining neutral alignment of the ankle and foot (5). Thisdevice provides a supportive total contact exoskeleton that maintains neutral forefoot and subtalar joints while allowing gradedamounts of ankle eversion, inversion, plantarfiexion and dorsifiexion.The DAFO is widely used, particularly in the pediatric population, and has several unique features. First, it allows graded footmotion within the orthosis so normal balance reactions involving proximal musculature can occur. Second, by providingsupport of the foot's natural arches, weight is more equally distributed throughout the foot. Thus, stimulation of foot reflexesbetter approximates normal function (6-8). Third, DAFOs provide secure medial-lateral stability and midline positioning,resulting in improved grading of ankle plantar- and dorsiflexion. This stabilization has proven so effective, many clinicians havenoted a decrease in abnormal plantarfiexion in patients wearing DAFOs. In one case, a 15-year-old spastic diplegic patientwith a resistant heel-cord contracture gained 15 degrees of passive dorsiflexion with knee extension as a result of wearingDAFOs for three months (4).The clinical effects of management with DAFOs are very promising. In one study, a four-year-old boy with spastic diplegiashowed significant increases in the duration and efficiency of balanced standing when wearing DAFOs as compared to hisperformance without these orthoses (5). In another study, the effects of DAFOs were reported on a 69-year-old male who was18 months post-CVA, who had no voluntary movement at the foot or ankle, and who demonstrated forceful hyperextension ofthe knee when wearing a conventional AFO (9). Within one month of receiving his DAFO, the patient demonstrated active toeextension and showed a 10-degree increase in knee flexion during toe-off. The author of this study attributed theseimprovements to the controlled mobility afforded by the DAFO. The effects of DAFOs on the temporal variables of gait werereported in a single-subject study by Diamond (10). The subject, a hemiplegic adult, showed significant increases in velocity,step length and stance time when wearing a DAFO as compared to his performance when barefoot. Although all of thesestudies are single-subject designs, the author of one such study defended this methodology by stating: "The single-subject
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