Search Results
The foot postures of 39 subjects were evaluated for excessive pronation by means of six static weightbearing and five nonweightbearing measurements, and two types of footprint indexes. Visual evidence of windlass function was recorded by video. Chi-square analysis revealed that excessive pronation does not affect the establishment of the windlass mechanism. The position of the forefoot relative to the rearfoot, subtalar joint axis position, and navicular drift/foot length ratio were significantly associated with dynamic windlass function. These results suggest that selected static measurements may have value in predicting some aspects of dynamic foot function during the propulsive phase of the gait cycle. (J Am Podiatr Med Assoc 91(5): 245-250, 2001)
This article presents a mechanical model that can be used to understand the foot, to help develop methods of treatment of foot pathology, and to provide direction for future research in foot mechanics and pathology. The anatomy and mechanical function of the windlass mechanism of the foot are analyzed using principles of mechanical engineering. The principles of force couples and free-body diagrams are explained and then applied to the foot. The relationship of the windlass mechanism to plantar fasciitis or heel spur syndrome, hallux abducto valgus, and hallux limitus is discussed.
Background
The windlass mechanism, first described by John Hicks in 1954, defines the anatomical and biomechanical relationship between the hallux and the plantar fascia. Hallux valgus (HV) and plantar fasciitis are the most common foot disorders, and, to date, no study has evaluated the relationship between these disorders. The purpose of this study was to determine the incidence of and factors associated with plantar fasciitis in patients with HV deformity.
Methods
In this prospective observational study, 486 patients with HV were divided into three groups according to stage of HV deformity. Patient sex, age, and body mass index were recorded. Presence of accompanying plantar fasciitis and heel spur was investigated by physical and radiographic examination. First metatarsophalangeal joint dorsiflexion of the affected side was measured. Patients with or without plantar fasciitis were also compared to evaluate factors associated with plantar fasciitis.
Results
Mean age and body mass index of the patients were significantly different among the three HV groups. The incidence of plantar fasciitis and heel spur significantly increased in correlation with the severity of HV deformity. Increased age and HV stage and decreased first metatarsophalangeal joint dorsiflexion were significantly associated with presence of plantar fasciitis in HV.
Conclusions
In this study, the incidence of plantar fasciitis was significantly increased in correlation with the severity of HV deformity. Significant association was found between plantar fasciitis and HV, which are anatomically and biomechanically related to each other by the windlass mechanism.
Abstract
Background: In patients with rheumatoid arthritis (RA), the pathological progression of lower limb biomechanics is established. Although specific aspects of RA gait patterns have been studied and described, we are aware of no studies of gait pattern compensations over the entire disease course. This study aimed to describe a model that could predict the evolution of lower limb pathomechanics in patients with RA.
Methods: A literature review was conducted of electronic databases (MEDLINE, PEDro, Trip Database, DOAJ, BioMed Central, PLOS clinical trial, ScienceDirect, and CRD York University, AHRQ, NICE, Cochrane Library) to October 3, 2023.
Results: A theory was developed that all people with RA induce or augment gait evolution syndromes following the same biomechanical course. Specifically, we postulate the “rheumatoid equinus syndrome,” the “rheumatoid abnormal pronation syndrome” and the “rheumatoid shuffle syndrome,” which have never been described before.
Conclusions: A new model of the evolution of gait compensation in RA is proposed. An important challenge of RA is that it increases the risk of ulcerative lesions, falls, pain, fractures, and healthcare costs. The proposed model can be used to reduce morbidity in this patient group by helping to explain and reduce the pain, deformity, and ankylosis of foot RA.
Background
We sought to determine whether patients with plantar fasciitis have limited dorsiflexion in the first metatarsophalangeal joint and which type of foot, pronated or supinated, is most frequently associated with plantar fasciitis.
Methods
The 100 study participants (34 men and 66 women) were divided into two groups: patients with plantar fasciitis and controls. The Foot Posture Index and dorsiflexion of the first metatarsophalangeal joint were compared between the two groups, and a correlation analysis was conducted to study their relationship.
Results
In the plantar fasciitis group there was a slight limitation of dorsiflexion of the hallux that was not present in the control group (P < .001). Hallux dorsiflexion and the Foot Posture Index were inversely correlated (Spearman correlation coefficient, −0.441; P < .01).
Conclusions
Participants with plantar fasciitis presented less hallux dorsiflexion than those in the control group, and their most common foot type was the pronated foot.
Functional hallux limitus is an underrecognized entity that generally does not produce symptoms but can result in a variety of compensatory mechanisms that can produce symptoms. Clinically, hallux limitus can be determined by assessing the range of motion available at the first metatarsophalangeal joint while the first ray is prevented from plantarflexing. The aim of this study was to determine the sensitivity and specificity of this clinical test to predict abnormal excessive midtarsal joint function during gait. A total of 86 feet were examined for functional hallux limitus and abnormal pronation of the midtarsal joint during late midstance. The test had a sensitivity of 0.72 and a specificity of 0.66, suggesting that clinicians should consider functional hallux limitus when there is late midstance pronation of the midtarsal joint during gait. (J Am Podiatr Med Assoc 92(5): 269-271, 2002)
Background: Diverse theories of orthoses application have evolved with the continual development of podiatric biomechanics and orthotic management. This theoretical disparity can lead to confusion in clinical, educational, and research situations. However, although approaches are varied, the common consensus is that foot orthoses outcomes are generally positive.
Methods: Three main podiatric theories exist: the foot morphology theory, the sagittal plane facilitation theory, and tissue stress theory. By researching the available literature, the perspectives of all three theories are summarized, emphasizing areas of conflict and agreement.
Results: Through a unified theory, we introduce a premise by which the similar orthotic outcomes obtained from the three main podiatric theories may be explained.
Conclusions: It remains up to the individual podiatric physician to decide which method to use to prescribe a foot orthosis. It may be of benefit to encompass all approaches rather than be dogmatic or exclusive. (J Am Podiatr Med Assoc 99(4): 317–325, 2009)
The implications of functional hallux limitus for lesser-metatarsal overload are discussed. A new method of treating functional hallux limitus is proposed, and three case histories are reviewed showing adequate resolution of symptoms using the proposed method of treatment. A proposed mechanism for the development of functional hallux limitus is discussed, and different methods of identification are illustrated. (J Am Podiatr Med Assoc 95(6): 593–601, 2005)
Functional Hallux Limitus
A Review
Functional hallux limitus is defined as a functional inability of the proximal phalanx of the hallux to extend on the first metatarsal head during gait. The theory concerning this anomaly and the altered gait characteristics that may result appears to have influenced the understanding of sagittal plane podiatric biomechanics. Although there is an increase in the body of evidence to support the proposed gait alterations, a detailed review suggests the need for further work. The aim of this article is to review the functional hallux limitus literature and its reported effects on gait. Furthermore, we explore some of the key and inherent problems with obtaining accurate data for joint motion measurement in the foot. With evidence-based practice now at the forefront of both clinical and academic practice, it is imperative to review the literature that underpins a particular commonly held or historical belief, in order to substantiate and validate subsequent diagnoses and treatments provided in light of this information. This is also true to advance the understanding of a particular anomaly or pathology and to inform so as to facilitate the provision of better care to patients. (J Am Podiatr Med Assoc 99(3): 236–243, 2009)
Biomechanical Consequences of Total Plantar Fasciotomy
A Review of the Literature
Background: Plantar fascia release for chronic plantar fasciitis has provided excellent pain relief and rapid return to activities with few reported complications. Cadaveric studies have led to the identification of some potential postoperative problems, most commonly weakness of the medial longitudinal arch and pain in the lateral midfoot.
Methods: An electronic search was conducted of the MEDLINE, ScienceDirect, SportDiscus, EMBASE, CINAHL, Cochrane, and AMED databases. The keywords used to search these databases were plantar fasciotomy and medial longitudinal arch. Articles published between 1976 and 2008 were identified.
Results: Collectively, results of cadaveric studies suggested that plantar fasciotomy leads to loss of integrity of the medial longitudinal arch and that total plantar fasciotomy is more detrimental to foot structure than is partial fasciotomy. In vivo studies, although limited in number, concluded that although clinical outcomes were satisfactory, medial longitudinal arch height decreased and the center of pressure of the weightbearing foot was excessively medially deviated postoperatively.
Conclusions: Plantar fasciotomy, in particular total plantar fasciotomy, may lead to loss of stability of the medial longitudinal arch and abnormalities in gait, in particular an excessively pronated foot. Further in vivo studies on the long-term biomechanical effects of plantar fasciotomy are required. (J Am Podiatr Med Assoc 99(5): 422–430, 2009)
