Abstract
M.Tech. (Chiropractic)
Problem Statement: Ankle sprains are one of the most common acute injuries treated by physicians (Pellow & Brantingham, 2001). Most ankle sprains involve the lateral ankle ligaments, with the anterior tibiotalar ligament being the most commonly affected in injuries involving plantarflexion and inversion. These injuries often result in restriction of movements that will limit gait (Crosbie, Green, Refshauge, 1999). Even in the event of injury to one ankle, the sensorimotor and postural deficits can be bilateral due to central processing of motor control information (Munna et. al., 2010, Monaghan et. al., 2006). The primary aim of a chiropractic adjustment is to increase joint range of motion (Fryer, Mudge, McLaughlin, 2002) and to correct local joint dysfunction (Pellow & Brantingham, 2001). No prior research has been done using the Zebris FDM-system to analyze changes in gait after ankle adjustment.
Method: Sixty participants between the age of 15 and 45 years were recruited. The participants were asked to sign a consent form after which a thorough case history, full physical exam and foot and ankle regional examination were performed. Participants were included in the study if they were of the correct age, had a chronic history of minor ankle sprain and had palpable motion restrictions of ankle joint range of motion. Participants were excluded if they had a history of severe ankle injury or ankle surgery, had any contraindications to chiropractic adjustment or were currently undergoing any other treatment that could interfere with the study, including the use of certain medications. Each participant underwent a gait assessment before and after they received a chiropractic adjustment to the restricted ankle joint.
Procedure: Objective measurements were obtained using the Zebris FDM-system before and after participants received one chiropractic adjustment using a long axis distraction technique. The Zebris FDM-system uses capacitive force sensors arranged on a platform in a high density. The measuring plate allows dynamic force distribution to be analysed during gait. The length of the Zebris platform allowed successive footfalls to be captured and measurements taken during three full gait cycles were used in the analysis. All data was processed using the WinFDM program to produce a gait report (Zebris Medical GmbH, 2008)
Results: A statistically significant change was seen in the single support line on the non-adjusted side. Changes were measured in the other gait parameters although they were not statistically significant.
Conclusion: This study has shown that chiropractic adjustment of the ankle joint has an effect on the path of centre of pressure and foot rotation during gait. It also helps clinicians to see that the adjustment has a bilateral effect. Future studies will be able to determine whether this is a positive or a negative outcome as the limits of normal and pathological gait using these parameters have not yet been set. Chiropractors can treat patients with a history of chronic ankle sprain more effectively if they have a better understanding of residual motion restrictions and movement patterns after acute ankle sprain. A future study including several treatments could be beneficial as clinical chiropractic practice would most likely involve more than one treatment of a patient with a history of ankle sprain. In this way the lasting and accumulative effects of chiropractic adjustment could be measured.