[Truncated abstract] Limitation of sagittal plane dorsiflexion, or hallux limitus (HL), represents the second most commonly encountered pathomechanical disorder affecting the first metatarsophalangeal joint, after hallux valgus (HV). The kinematic role of the first metatarsophalangeal joint represents an integral component of the gait cycle. It has often been reported that for adequate leverage and propulsion to occur during normal gait, the hallux must be able to dorsiflex approximately 65° on the head of the first metatarsal. Secondary gait compensation mechanisms have often been observed clinically as a result of HL. The effect of HL on gait can be reflected in transverse plane alteration of the foot in relation to the line of progression during gait, defined as the angle of gait (AOG). The first purpose of this study served to investigate potential differences in dynamic angle of gait AOG in subjects with HL compared to a control group. A validated technique using coloured powdered footprints was used to quantify AOG. Furthermore, it was required to establish whether the relative amount of transverse plane motion observed in the AOG was related to factors intrinsic or extrinsic to the foot. Intrinsic factors such as the amount of forefoot to rearfoot abduction was considered, and achieved by measuring the rearfoot to forefoot axis (RFA) angle using a weight bearing composite (COMP) view radiograph. The remaining objectives of the study served to investigate other common aetiological factors associated with HL and their potential influence on AOG in subjects with HL ... Results further indicated that the amount of first metatarsophalangeal joint dorsiflexion did not appear to influence AOG in the two groups, and that AOG did not reflect the iii amount of forefoot to rearfoot abduction in a foot with HL compared to the control group. When comparing foot type, as indicated by CIA, it appeared AOG did not significantly alter between the HL and control groups. Finally, the results indicated AOG did not differ significantly between subjects with unilateral HL. This thesis study indicated that with the current sample population, the wide variability in AOG prevented detection of any subtle differences that may exist in subjects with HL. Results also emphasised the need to incorporate other variables such as symptomology and foot dominance when considering the effects first metatarsophalangeal joint pathology might have on HL, such as AOG.
|Unpublished - 2004