The Effect of Forefoot and Arch Posting Orthotic Designs on First Metatarsophalangeal Joint Kinematics During Gait

Abstract

Study Design: Repeated-measures analysis of variance. Objective: To examine the effect of 2 different orthotic posting designs on first metatarsophalangeal (first MTP) joint kinematics during gait. Background: Common orthotic designs used to control abnormal pronation incorporate the use of a medial post in the forefoot and/or rearfoot locations. Although this design may favorably alter rearfoot and lower-limb kinematics, the incorporation of a forefoot post has been theorized to negatively impact first MTP joint function by limiting hallux dorsiflexion during push off. An alternative design that has been proposed to be more favorable for function of the hallux and first metatarsal is the medial arch support. Methods and Measures: Eighteen subjects with a mean age of 28.2 years (SD, 8.3 years) completed the study. All subjects were judged to have excessive pronation based on a clinical orthopaedic examination. Two different pairs of orthoses were custom molded for each subject. One design incorporated an extrinsic rearfoot and forefoot post and the second design had a high medial longitudinal arch in combination with an extrinsic rearfoot post. The ''Flock of Birds'' electromagnetic tracking device was used to collect 3-dimensional position and orientation data of 3 body segments (hallux, first metatarsal, and calcaneus) during the stance phase of walking for 3 conditions (no orthosis and each of the 2 different orthotic designs). A repeated-measures analysis of variance was used to assess differences in first MTP joint dorsiflexion at midstance and during the push-off period of gait, as well as metatarsal declination angle changes during relaxed stance. An exploratory regression analysis was used to investigate factors that related to the change in peak dorsiflexion for the orthotic conditions. Results: Peak first MTP joint dorsiflexion averaged between 38°and 40°across all conditions. Although slight increases in first MTP joint dorsiflexion values were noted with both types of orthotic designs, these differences were not significant at either phase of the stance cycle (P = .50). The metatarsal declination angle in relaxed stance significantly increased (P = .001) under both orthotic conditions. Considerable individual variability was present. For the rearfoot-forefoot posted orthosis, a change in the declination angle of the first metatarsal during relaxed stance with the orthosis was a significant nonlinear predictor of change in peak dorsiflexion during push off. Deborah A. Nawoczenski, Professor, Ithaca College, University of Rochester Campus, 300 East River Road 1-102, Rochester, NY 14623. E-mail: dnawoczenski@ithaca.edu Conclusions: Foot orthoses that incorporate a medial forefoot post do not have a consistent negative effect of reducing first MTP joint dorsiflexion during walking.

Biomechanical Effect of Foot Orthoses on Rearfoot Motions and Joint Moment Parameters in Patients with Flexible Flatfoot

“…The results from this study revealed that peak everted position values of RFM in the type A insole and type B insole (2.89±3.10° and 2.70±2.40°, respectively) in the longitudinal axis was significantly smaller than that of the normal insole (5.40±4.10°) (Table 2). This result was consistent with the findings of previous studies [39–42], which reported that the peak rearfoot eversion was significantly reduced with a medial forefoot and rearfoot posting insole inserted to the foot. Also, the forefoot adduction (1.6°) was made by the functional insole [43], resulting in a decrease forefoot pronation which could positively have an effect on the everted position of rearfoot in patients with flatfoot [44].…”

Effect by custom-made foot orthoses with added support under the first metatarso-phalangeal joint in hallux limitus patients

“…Using this type of orthoses, Kilmartin et al 30 failed to improve the extension of the hallux either in HL patients or in healthy participants, but Munuera et al 31 achieved an improvement of 8° after 5 months of treatment in patients of ages from 25 to 32 years. According to Nawoczenski and Ludewig, 32 control of pronation and increasing the medial longitudinal arch of the foot did not imply any improvement in the range of dorsiflexion of the hallux. One of the conclusions drawn in that study was that the degree of plantarflexion of the first metatarsal is directly proportional to the dorsiflexion of the hallux, thus coinciding with the purpose of our first measurement (relaxed position of the first MPJ).…”

Clinical improvement in functional hallux limitus using a cut-out orthosis

“…Participants were excluded if they had established hallux valgus, a previous history of foot and ankle trauma, fracture, surgery, or an existing diagnosis of inflammatory, metabolic, neurological, or vascular disease. Individuals were also excluded from the study if they exhibited less than 40° of available first MTP joint dorsiflexion (as measured using a nonweight-bearing technique previously described by Buell et al 9 This has been reported to be the range of first MTP joint dorsiflexion used during normal propulsion 10 –12 and would, therefore, have indicated structural limitation at the joint. In addition, no subject had a history of congenital deformity, pain, or traumatic injury involving either of their lower extremities during the 6 months prior to study enrollment.…”

“…Push off was defined as the period of gait between heel off and toe off, which was the time when peak dorsiflexion of the first MTP joint and metatarsal declination angle due to plantarflexion at first metatarsal cuneiform joint occurred in the three planes. 11…”