Biomechanical Assessment of PassiveAnkle Joint Complex DorsiflexionAlfred Gatt2013thesis submitted in partial fulfilment of the requirement of Staffordshire University for thedegree of Doctor of Philosophy
Year: 2012
Type: dissertation
Abstract: \n \n \nThe measurement of ankle joint dorsiflexion is an important component of the clinical examination \nof the foot and is also an outcome measure often employed in research. Diagnosis of ankle equinus \nor limited ankle dorsiflexion is based solely on this measurement. Although a great majority of \nresearch papers in this field utilise normal clinical goniometers for obtaining the maximum ankle \ndorsiflexion angle (MADA) and important clinical decisions are based on these findings, there is \noverwhelming evidence that this method is highly unreliable. Thus this thesis aimed to investigate \nalternative methods of measuring ankle dorsiflexion and various issues that affect the MADA in \norder to obtain a clear picture of foot segment movement from which an Ankle Goniometer could be \nconsequently designed and validated. \n \nTen different techniques were identified that included various apparatuses designed specifically \nfor measuring ankle dorsiflexion. However, during validation, their methodological quality would \nhave benefitted from the use of an actual patient population and comparison with a reference \nstandard, which caused papers to score poorly on methodological quality assessment. It was \nconcluded that issues affecting this measurement and that needed to be researched further include: \nfoot posture, the amount of moment applied and the stretching characteristics of the calf muscle \ntendon unit. \nExperiments within this study indicated that in adults, the mean maximum pronated angles were \nalways higher than in other postures, with 8.27o difference between the pronated and supinated \npostures (p=0.032) and 5.78o between pronated and neutral (p=0.000). However, the reported \ndifference between neutral and supinated (mean angle of 2.49o) is of little clinical significance. \nIt was observed that the forefoot always travels through a greater angle than the hindfoot in all 3 \nfoot postures, while the hindfoot to forefoot angle increases during the application of a moment, \nindicating that the ‘midtarsal joint locking mechanism’ cannot be applied to passive dorsiflexion \nof the foot. In adolescents, there are no significant differences in the mean MADA between the 3 \npostures, implying that this measurement technique may be performed in any of these postures. It \nwas also concluded that there is no need to control moment applied during this measurement \nprocedure to produce consistent results between raters and that the calf muscle tendon unit does \nnot stretch significantly following brief repetitive passive stretching. \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \nii \n \n \n \n \n \n \n \n \nAn ankle goniometer that measured purely hindfoot movement by eliminating forefoot influence and \nthat increased reliability by holding the foot in the chosen posture, was consequently designed. \nThis was validated by synchronizing with an electrogoniometer and an optoelectronic motion capture \nsystem. Reliability testing, with the foot held in a supinated posture as opposed to the \ntraditional Rootian method of placing the foot at subtalar joint neutral position, spanned a number \nof different trials, including intra-tester and inter-tester reliability studies utilising both \ncontrolled and uncontrolled conditions, in convenience samples of healthy participants and a random \nsample of patients. Reliability testing between 4 raters with little experience on the utilization \nof this device was finally conducted. It has been shown that the Ankle Goniometer is a valid and \nreliable device for measuring ankle joint complex dorsiflexion both in healthy adults and in a \npatient population.
Author: Alfred Gatt
Language: English
Topic: Foot and Ankle Surgery
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W178747951