Ankle function alterations following acute ankle sprains over a 14 day period

The University of Toledo The University of Toledo Digital Repository Theses and Dissertations 2014 Ankle function alterations following acute ankle sprains over a 14 day period Michael Sean Patrick Mayes University of Toledo Follow this and additional works at: http://utdr.utoledo.edu/theses-dissertations Recommended Citation Mayes, Michael Sean Patrick, "Ankle function alterations following acute ankle sprains over a 14 day period" (2014). Theses and Dissertations. 1731. http://utdr.utoledo.edu/theses-dissertations/1731 This Thesis is brought to you for free and open access by The University of Toledo Digital Repository. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of The University of Toledo Digital Repository. For more information, please see the repository's About page.

A Thesis entitled Ankle Function Alterations Following Acute Ankle Sprains Over a 14 Day Period by Michael S. P. Mayes, ATC Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Exercise Science Phillip Gribble, PhD, Committee Chair Brian Pietrosimone, PhD, Committee Member Abbey Thomas, PhD, Committee Member Patricia R. Komuniecki, PhD, Dean College of Graduate Studies The University of Toledo August 2014

Copyright 2014, Michael Sean Patrick Mayes This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author.

An Abstract of Ankle Function Alterations Following Acute Ankle Sprains Over a 14 Day Period by Michael S. P. Mayes Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Exercise Science The University of Toledo August 2014 Objective: The objective of this study was to determine the effects of an acute lateral ankle sprain on self-reported function, self-reported pain, self-reported global function, joint effusion, dorsiflexion range of motion, and dynamic stability over a 14 day period following injury compared to healthy matched controls. Design and Setting: A casecontrol design was conducted in a laboratory setting. Subjects: Twenty-nine participants with an acute lateral ankle sprain (LAS) were assigned to a LAS group (10 males, 19 females; 20.41 ± 2.18 years; 176.44 ± 11.00 cm; 74.22 ± 14.33 kg), and twenty-two healthy participants were assigned to a control group (11 males, 11 females; 20.95 ± 2.97 years; 178.61 ± 10.96 cm; 76.39 ± 13.81 kg). Procedure: Experimental measures All participants were asked to report for a total of five tests sessions done at 36 hours, 5, 7, 10, and 14 days following initial injury; or from the day of enrollment as a healthy control. Each testing session lasted approximately 1 hour, with self-reported function and self-reported pain was assessed using the FADI, FADI Sport and VAS. Dynamic balance was assessed using the SEBT anterior, posteromedial, and posterolateral reach directions. Ankle girth was measured using the figure-of-eight method. Dorsiflexion range of motion was assessed using a goniometer. Frequency of rehabilitative exercises athletic, athletic iii

participation and use of therapeutic modalities was collected using a treatment questionnaire. Results: Significant differences were found fourteen days following injury in all self-reported outcomes in the LAS group compared to Healthy controls (P 0.05). Significant decreases DF were found up to seven days post injury (P 0.05). Significant dynamic stability deficits were seen up to fourteen days following injury in the anterior reach and posteromedial reach of the star excursion balance text (SEBT) (P 0.05). No significant findings were seen in the posterolateral reach direction of the SEBT (P 0.05) at any time point. No significant findings were seen in ankle girth (P 0.05) at any time point. Conclusion: Those who suffer from a LAS exhibit decreased self-reported function, decreased dynamic postural control, decreased DF range of motion, increased self-reported pain, and increased ankle girth. While studies investigating acute function alterations in ankle sprains for 14 days following injury are limited, these results should be taken into consideration when making rehabilitation and return-to-play decisions. Clinicians may need to consider the possibility that a LAS return-to-play protocol time frame should be increased further than two weeks post injury. Word Count: 396 iv

For mom, dad, and Jessica. You guys are my constant source of motivation and happiness.

Table of Contents Abstract Table of Contents List of Tables List of Abbreviations iii vi ix x I. Introduction 1 A. Problem Statement 3 B. Purpose Statement 4 C. Dependent Variables 4 D. Independent Variables 5 E. Hypotheses 5 II. Literature Review 7 A. Lateral Ankle Sprain (LAS) 7 B. Chronic Ankle Instability 8 C. Dynamic Postural Control 10 D. Star Excursion Balance Test 12 E. Dorsiflexion Limitations 15 F. Foot and Ankle Disability Index (FADI) 15 III. Methods 18 A. Study Design 18 B. Participants 18 C. Procedures 19 D. Foot and Ankle Disability Index 19 vi

E. Star Excursion Balance Test 20 F. Visual Analog Scale 21 G. Treatment Questionnaire 21 H. Dorsiflexion Range of Motion and Ankle Girth 21 I. Statistical Analysis 22 IV. Results 23 A. Self-Reported Measures 23 B. Dorsiflexion and Ankle Girth Measures 24 C. Dynamic Postural Control Measures 24 V. Discussion 26 A. Self-Reported Measures 26 B. Dorsiflexion and Ankle Girth Measures 30 C. Dynamic Postural Control 31 D. Limitations 33 E. Future Research 33 F. Conclusion 34 References 35 Appendices A. Tables 38 B. Consent Form 48 C. Foot and Ankle Disability Index 54 D. Star Excursion Balance Text Form 56 E. Treatment Questionnaire 57 vii

F. Ankle Range of Motion Form 59 viii

List of Tables Table 1 Means and Standard Deviations for Participant Demographics...38 Table 2 Foot and Ankle Disability Index...38 Table 3 Foot and Ankle Disability Index Sport...39 Table 4 Visual Analog Scale Pain...39 Table 5 Visual Analog Scale Function...40 Table 6 Global Function...40 Table 7 Dorsiflexion Range of Motion...41 Table 8 Ankle Girth...41 Table 9 Star Excursion Balance Test Anterior...42 Table 10 Star Excursion Balance Test Posteromedial...42 Table 11 Star Excursion Balance Test Posterolateral...43 Table 12 FADI and FADI Sport Effect Sizes...44 Table 13 Dorsiflexion and Ankle Girth Effect Sizes...45 Table 14 VAS and Global Function Effect Sizes...46 Table 15 Star Excursion Balance Test Effect Sizes...47 ix

List of Abbreviations ADL...Activities of Daily Living CAI..Chronic Ankle Instability DF Dorsiflexion FAI..Functional Ankle Instability FADI Foot and Ankle Disability Index ICC..Intraclass Correlation Coefficient LAS..Lateral Ankle Sprain MAI.Mechanical Ankle Instability ROM...Range of Motion SEBT Star Excursion Balance Test VAS..Visual Analog Scale WBLT..Weight Bearing Lunge Test x

Chapter 1 Introduction Lateral ankle sprains (LAS) are one of the most common athletic injuries in all sporting arenas and are a frequently seen by Athletic Trainers. 1 It is estimated that almost 23,000 ankle sprains occur daily in the United States, 2 with about 85% of those sprains affecting the lateral ligamentous structures. 3 Depending on the severity of the sprain an athlete may have symptoms for months or even years after initial injury. 4, 5 With conservative management and detailed, succinct rehabilitation, athletes theoretically should be capable of returning to play with little to no residual side-effects. However, residual symptoms may be present due to inadequate return-to-play protocols allowing athletes to return to play with less than 100% of functional ability, decreased range of motion (ROM), and increased pain, when compared to prior injury status. While most ankle sprains are not seen as severe injuries, improper management can result in the development of chronic ankle instability (CAI). 6 CAI involves bouts of recurrent ankle sprains brought about by chronic symptoms of persistent weakness, instability, and pain. The incidence of residual symptoms and bouts of instability have been reported with varying rates between 40 and 50%. 3, 7, 8 Currently, the best predictor for CAI is previous lateral ankle sprain, 6, 9-11 indicating that clinicians may often underestimate the severity of acquiring an ankle sprain. Current treatment strategies and rehabilitation protocols may be ineffective in preventing residual, lasting symptoms that lead to the onset of CAI. 6 Further understanding of the underlying symptom progression is needed to effectively develop new rehabilitation strategies to alleviate the residual dysfunction associated with CAI. 1

Current treatment strategies for an ankle sprain will undoubtedly address range of motion, strength, and balance deficits in order to return a patient to his/her full health. However, clinicians may overlook the self-reported outcomes of their own patients and return them back to sport or work participation without fully alleviating the symptoms, which may leave individuals susceptible for further injury. The ability to quantify selfreported function is an invaluable resource clinicians can use to track progress through a rehabilitation program. Subjective reports of function completed by patients are becoming an essential part of clinical practice for health care practitioners. 12 Subjective measures allow clinicians to assess changes in a patient s functional limitations and disabilities after designed clinical interventions. 13 The Foot and Ankle Disability Index (FADI) and Foot and Ankle Disability Sport (FADI Sport) assesses the level of perceived disability in the ankle complex during activities of daily living and during sport activities, respectively. To date, there has been no application of the FADI tools in assessing the capability of a patient to return to his/her desired activity. Following a grade one LAS, the current average return-to-play time for an athlete is between 3-7 days; 14, 15 however, self-reported symptoms of decreased function may be lasting for months following injury. 4, 5 Clinicians may be underestimating the length of time decreases in self-reported functional ability are seen which may be causing them to advance patients through rehabilitation protocols too quickly. Returning an athlete to activity prior to the return of his/her full functional ability may be putting the individual at risk for further injury and CAI. Dorsiflexion (DF) range of motion has been shown to commonly be restricted following LAS and may add to residual symptoms which contribute to CAI. 6, 16, 17 These 2

restrictions, along with proprioceptive deficits may lead to increased susceptibility to further injury and repetitive bouts of LAS. 18 Proprioceptive deficits have been seen to be a common impairment after LAS, 16 which is why rehabilitative protocols rigorously address static and dynamic balance. Dynamic postural control deficits, measured by the Star Excursion Balance Test (SEBT), have been observed in patients with CAI. 19 Identification of factors that restrict patient rehabilitation gains and contribute to residual instability may help clinicians and researchers develop more effective interventions for LAS injuries and prevent CAI development. Residual symptoms of recurrent LAS could significantly impair individuals functional ability and movement patterns, decreasing their physical activity level through their life spans. 20 With evidence documenting the progression or regression of symptoms related to self-reported function, self-reported pain, global function of how each participant is feeling overall through all activities, DF range of motion, joint effusion, and dynamic postural control, we may be able to better equip clinicians to return athletes to full participation in a safer manner with less recurrence of injury and residual symptoms past their athletic careers. Problem Statement Limited research has been conducted on the effects of an acute lateral ankle sprain on self-reported function, self-reported pain, self-reported global function, DF range of motion, ankle joint effusion, and dynamic balance and how these symptoms progress over a 14-day period. It is likely that misunderstanding of the progress of patient outcomes leads to accelerated return to play protocols for ankle sprains, which may be contributing to the development of ankle sprain recurrence. 3

Purpose Statement The primary purpose of this study was to determine the effects of an acute lateral ankle sprain on self-reported function, disability, and pain, as well as joint effusion, DF range of motion, and dynamic stability over a 14 day period following injury compared to healthy controls. Dependent Variables 1) Foot and Ankle Disability Index (FADI) Participants were given a 26 item subjective questionnaire on their reported disability within activities of daily living 2) Foot and Ankle Disability Index Sport (FADI Sport) Participants were given an 8 item subjective questionnaire on their reported disability within sport performance 3) Visual Analog Scale for self-reported ankle function Participants were given a 10 cm subjective scale and asked to report their functional ability 4) Visual Analog Scale for self-reported pain Participants were given a 10cm subjective scale and asked to report their pain 5) Global Function 4

Participants were asked to rate their own global functional ability on a 0-100% scale 6) Dynamic Postural Control Assessed using the Star Excursion Balance Test. Reach directions used included anterior, posteromedial, and posterolateral 7) Ankle Girth Assessed using the Figure-of-Eight Measurement method 8) Dorsiflexion Range of Motion Actively assessed using a goniometer 9) Treatment Questionnaire Participants were given a questionnaire and were asked to report all treatment they had been receiving for their lateral ankle sprain 10) Return-To-Play Time Intercollegiate Athlete: Determined by when the participant was cleared for full participation by their ATC Non-Athlete: Determined by when the participant felt they were fully functional and could return their activities Independent Variables Group (LAS/control) 5

Limb (injured/non-injured) Time (36 hours, 5days, 7 days, 10 days, and 14 days postinjury/enrollment in the study) Hypotheses 1) The LAS group will exhibit decreases in self-reported disability, self-reported pain, self-reported global function, dorsiflexion range of motion, and dynamic postural control while displaying increases in ankle girth, and self-reported pain, when compared to matched control participants. 2) The LAS group will exhibit a positive relationship between time lapsed within the 14 day testing and increases in dorsiflexion range of motion, dynamic postural control, and self-reported function, and decreases in ankle girth and self-reported pain and disability. 3) No change will be observed within the control group in self-reported function, disability, pain, global function, or dorsiflexion range of motion, dynamic postural control and ankle girth over the 14 day testing period. 6

Chapter 2 Literature Review Lateral Ankle Sprains (LAS) The LAS has one of the highest occurrence rates among athletes, consisting of 10-30% of injuries. 1, 21, 22 It is reported that over 23,000 ankle sprains occur in the United States per day, which is estimated to one sprain per 10,000 people daily. 2 A LAS occurs with extreme inversion and plantar flexion of the ankle. Signs and symptoms associated with this injury include swelling, redness, heat, pain, and loss of function: in short, all of the signs inflammation, as well as ecchymosis. An athlete may hear a snap or pop during the moment of injury which can signify a rupture of one or more ligaments within the lateral ligament complex consisting of the anterior talofibular ligament (ATF), posterior talofibular ligament (PTF), and calcaneonavicular ligament (CF). The anterior talofibular ligament (ATF) and calcaneonavicular ligament (CF) are relatively weak and prone to rupture following the injury mechanism. 23 The ankle joint is formed by a complex array of bony articulations, static ligamentous supports, and musculotendinous attachments, which allow for static and dynamic stabilization. The bony articulations are comprised of three distinct joints: The talocrural joint, the subtalar joint, and the distal tibiofibular joint. The talocrural joint consists of the dome of the talus, and the mortise formed by the distal articulation of the tibia and fibula. 6 Thought of as a hinge joint, allowing for isolated planter flexion and DF movements primarily within the sagittal plane, the axis of rotation of the talocrural joint 7

passes through the lateral and medial malleoli. 6 When the ankle is fully dorsiflexed ligamentous support is crucial to prevent excess articular translations. 6 The talocrural joint receives its lateral ligamentous support from. The medial support comes from the deltoid ligament. The ATF and CF provide support against excessive inversion of the ankle, and are injured following a LAS 85% of the time. 3 Depending on the severity of the sprain, an athlete may have symptoms for months or even years after initial injury. 4, 5 With conservative management and detailed, succinct rehabilitation, athletes theoretically should be capable of returning to play with little to no residual side-effects. Residual dysfunction could present as deficiencies in self-reported function, self-reported pain, dynamic stability 6, dorsiflexion (DF) range of motion 16, and strength. 6 As a result, recurrence rates of ankle sprains can be as high as 80%. 8 Currently, the best predictor for multiple ankle sprains is the history of at least one LAS, 6, 9-11 which may indicate that the severity of an athlete acquiring an ankle sprain may often be underestimated by clinicians. 24-28 Chronic Ankle Instability CAI involves bouts of recurrent ankle sprains brought about by chronic symptoms of persistent weakness, instability, and pain, and is also accompanied by a subjective feeling of the ankle giving way. 6 CAI can be divided into mechanical ankle instability (MAI) and functional ankle instability (FAI), which combine together to create the residual symptoms following initial injury. Tropp et al. 29 first described MAI as a cause of CAI due to pathologic ligament laxity subsequent an ankle ligament injury. MAI is thought to be a cause of CAI due to 8

anatomic changes after the initial ankle sprain, which eventually lead to insufficiencies that predispose individuals to multiple ankle sprains. 6 These anatomic changes are thought to include pathologic ligament laxity, impaired arthrokinematics, synovial inflammation and impingement, and degenerative joint disease. 1, 6 It has also been defined as motion beyond the normal physiologic range of motion. 30 FAI is the subjective sense of joint instability and impairment caused by inhibition of the proprioceptive and neuromuscular control of the foot and ankle. 6, 31 Postural control deficits seen in these individuals affected by FAI are expected to be a result of a combination of impaired proprioception and neuromuscular control. 6 Changes such as these limit an individuals dynamic stability and hinder ones ability to minimize sway following external perturbation, possibly leading to a predisposition for recurrent episodes of instability. 6 MAI and FAI may occur independent of each other; however, they are usually not mutually exclusive, because both can result in the chronic giving way of the ankle associated with CAI. Currently, the exact reason an individual acquires CAI is unclear; however, investigators are suggesting that neuromuscular factors contribute to ankle instability by disrupting the normal function of the uninjured muscles surrounding the injured joint. 16, 32 Understanding these neuromuscular responses after an injury to the ankle joint may provide clinicians and researchers with essential information that leads to improved treatment protocols. Effective prevention of recurrent ankle sprains relies on ascertaining the mechanisms responsible for these neuromuscular dysfunctions. It is hypothesized that a LAS damages the lateral mechanoreceptors, which creates altered neuromuscular feedback due to changes in afferent inputs to the spinal cord. 28 This alteration is thought to inhibit spinal reflex excitability by decreasing the motor neuron 9

pool excitability (MNPE) to the surrounding ankle musculature, thereby causing a deficit in reflexive motor output. 25 This phenomenon in which the body reflexively decreases the excitability of an injured joint s surrounded musculature is termed arthrogenic muscle inhibition (AMI). 24, 25 Deficits seen in dynamic postural control, strength, and range of motion can lead to a high rate of recurrent ankle sprains and potentially MAI and/or 3, 6, 9, 10 FAI. Dynamic Postural Control Injury to the lateral ligament complex of the ankle can result in debilitating effects to the dynamic support of the ankle. 6 Neuromuscular feedback and proprioception provide essential information to the brain and spinal cord for maintaining dynamic balance and stability, while also helping to prevent injury. 33 An injury to the ankle joint will result in proprioceptive deficits, which will then be followed by a decrease in neuromuscular control. 6 These decrements adversely affect an individual s dynamic postural control and predispose them to recurrent instances of instability. 6 This predisposition could explain the residual instability related to FAI. Hertel et al. 6 describes the deficits in dynamic stability following LAS to be a compounding effect stemming from nerve conduction velocity, neuromuscular response time, static postural control, and strength. Impaired nerve-conduction velocity has been seen in the common fibular nerve following acute LAS, which provides researchers with an objective measure of functional instability. 34, 35 Slowed neuromuscular response times have also been demonstrated in individuals with a history of LAS. 36 Konradsen et al. 36 examined muscle activity, joint motion, and alteration of body center of pressure during sudden inversion through external perturbation in 15 participants with a history of ankle instability and 15 10

healthy controls. Researchers found a prolonged reaction time in the unstable ankles, which examiners believe enforces the theory of proprioceptive deficits being linked to ankle instability. 36 Strength deficits have been reported in individuals with a history of ankle sprains 37 and may be linked to alterations seen in dynamic postural control. 6 However, the extent of relation between strength and dynamic postural control is not known, and strength deficits do not necessarily mean that balance impairments will follow. Hertel et al. 6 explained that strength deficits can be due to impaired neuromuscular recruitment, muscle damage, or muscle atrophy. The individual symptoms of dynamic instability are not mutually exclusive, but occur in tandem with each other. Joint injury causes proprioceptive and neuromuscular control deficits, which negatively affect dynamic stability of the ankle and can lead to the predisposition of further ankle injury. 6 Dynamic postural control can be assessed when the patient attempts to maintain a stable base of support while completing multiple functional and dynamic movement patterns. 19 This may involve hopping or jump landing and immediately upon ground impact attempting to remain motionless in a stable base of support. 19 Or this could involve purposeful reaching with a selected body segment while attempting to maintain a stable base of support. 19 In doing so, we may also ascertain, to an extent, the individual s strength and range of motion. The Star Excursion Balance Test (SEBT) is such a test in which it is possible to inquire these measurements. 19, 38 Clinicians may use the SEBT as a 11

way to measure the dynamic postural control deficits following an ankle sprain and as a tool to objectively measure improvements during a rehabilitation program. Star Excursion Balance Test The ability to maintain balance during a dynamic task is clinically relevant in injury prevention, as balance deficits can result in recurrence of LAS. 16 The ability of clinicians to be able to objectively measure a patient s balance and dynamic postural control may play a paramount role in injury prevention. The SEBT gives the clinician a 19, 38, 39 low-cost, reliable testing system that can be utilized in a time efficient manner. Munro et al 39 conducted a study to determine the reliability of using the SEBT in a clinical setting by examining the learning effect, test-retest reliability, and measurement error. 39 Their results indicated that there is high test-retest reliability with intraclass correlation coefficients (ICC) of 0.84-0.92 for all 8 reach directions. 39 When administering the SEBT researchers suggest that 4 practice trials be performed to account 39, 40 for a learning effect. Originally designed as a grid pattern on the ground resembling a star, with the 19, 39 eight lines 45 degrees away from each other and extending out from one center point. Each of these designated lines serves as reach guidance for the patient completing the test. While maintaining a stable base of support on the stance leg, the patient reaches with the contralateral limb and touches their toe against the line once maximal distance is reached. When maximum reach distance is achieved the clinician records the distance, and the patient returns to a tandem stance while maintaining dynamic stability. In order to perform these reaching tasks and attain a desirable score the stance leg requires ankle 12

dorsiflexion, knee flexion, hip-flexion range of motion along with ample strength, proprioception, and neuromuscular control to perform each dynamic reaching task. 38 If only a short distance is achieved by the patient there may be a mechanical issue, sensorimotor system deficit, 41 or a lack of dynamic postural control. 19 Performance in the SEBT may be influenced by specific anthropometric and physiologic measures and normalization of the reach distances are necessary for accuracy purposes. Munro and Herrington 39 believed that when comparing separate individuals it is important to normalize the reach distances by leg length. The leg length is determined by measuring from the anterior superior iliac spine to the medial malleolus of the individual while lying supine. 39 To normalize the reach distance each reach distance is divided by the individual s leg length and multiplied by 100. 39 When Gribble and Hertel 42 compared the raw scores of healthy men and women they found that men were able to reach significantly farther, on average, than women in all eight directions of the SEBT. The researchers considered this difference may be due to the men being taller and, naturally, having longer legs than the women. They then normalized all of the reaching scores to leg length and found that the differences between sexes no longer existed in the data. Evidence now exists supporting the use of only three of the eight reach directions: the anterior, posteromedial, and posterolateral directions. 40 With a decrease in subsequent reach directions needed, researchers have substantially streamlined the administration of the SEBT. Researchers 40, 43 have shown a functional redundancy exists within administration of all 8 directions, and that validity of the test is not compromised when only performing the three reaching directions. Using the anterior, posteromedial, and 13

posterolateral reach directions gives us a sufficient measurement of an individuals dynamic postural control. 40 Researchers suggest that once you have normalized all of an individual s scores on the three reach directions a composite score should be calculated. A composite reach distance gives clinicians a comprehensive view of how each individual performed on the SEBT, and is determined by the sum of all three reach directions divided by three times the limb length, multiplied by 100. 44 The SEBT is a useful tool for objectively measuring a patient s dynamic balance following LAS and track improvement through a rehabilitation protocol 19, 38, however, another important clinical application for the SEBT is using the measured amount of dynamic stability as a predictor of risk for an injury to the lower extremity. 19, 44 Limited research has been conducted on the ability of the SEBT to be predictor of injury to lower extremity joint, however, Plisky et al. 44 yielded significant results linking reach distance to lower extremity injury. Researchers tested high school basketball players from 7 different schools before the start of their competition season, while documenting any lower extremity injuries throughout the season. They reported that players with a right-toleft difference, in the anterior direction, of greater than 4cm were 2.5 times more likely to suffer a lower extremity injury. Also, specifically female basketball players with a composite score of less than 94% of their limb length are 6.5 times more likely to suffer a lower extremity injury. 44 Hoch et al 45 performed a study examining the relationship between DF range of motion measured with the Weight Bearing Lunge Test (WBLT) and normalized reach directions in the anterior, posteromedial, and posterolateral directions of the SEBT. Once normalized, researchers found a significant correlation between the anterior reach 14

direction and DF range of motion (r = 0.53, r 2 = 0.28) (p < 0.001). 45 The statistical results indicate that 28% of the variance in the anterior reach direction of the SEBT can be accounted for by DF range of motion. The researchers suggested that the anterior reach direction of the SEBT may be a good clinical test to assess the effects DF restrictions have on dynamic postural control. 45 Dorsiflexion Limitations During non-weight bearing DF the talus rolls and glides posteriorly in relation to the calcaneus, 41 however, while in gait the tibia will translate anteriorly on the talus. DF is decreased following a LAS and is thought to contribute to the functional instability associated with multiple ankle sprains. 16 DF limitations can be caused by an excessively anterior positioned talus creating abnormal or restricted posterior, 46 and potentially creating an abnormal axis of rotation at the talocrural joint. 6 If the talocrural joint is unable to fully dorsiflex, it will not reach a complete closed-pack position during stance, and therefore, will be vulnerable to an injurious mechanism. 6 This deficit, along with being linked to functional instability, 16 may contribute to an impaired sensorimotor system function. 46 This is theorized to occur by disrupting the normal transmission of afferent information related to alterations in ankle rotation and tracking of the articular surfaces. 46 Restoration of normal DF range of motion following an acute LAS may help decrease an individual s susceptibility to future ankle sprains. 18 Foot and Ankle Disability Index (FADI) Traditionally, clinically measured outcomes for joint ability after injury include strength, range of motion, and subjective balance assessment. In conjunction with these 15

measures, goals are produced by clinicians and are completed by patients, throughout a rehabilitation program. These goals help clinicians make objective and safe return-to-play decisions. However, clinicians may overlook self-reported functional limitations and disabilities experienced by patients. The ability to quantify self-reported function is an invaluable resource clinicians can use to track progress through a rehabilitation program. Subjective reports of function completed by patients are becoming an essential part of clinical practice for health care practitioners. 12 Subjective measures allow clinicians to assess changes in a patients functional limitations and disabilities after designed clinical interventions. 13 The Foot and Ankle Disability Index (FADI) was designed to give clinicians such a tool to assess the amount of self-reported disability related to foot and ankle pathologies. The Foot and Ankle Disability Index Sport (FADI Sport) allows the clinician to break down sport specific tasks for greater sensitivity in functional limitations. 13 The FADI was developed to be region and task specific, covering aspects of activities of daily living. 13 The FADI Sport assesses more dynamic tasks which are more specific to athletic participation in order to detect deficits in higher functioning participants. 13 Each task is given a score by the patient; 0 (unable to do) to 4 (no difficulty at all). There are also 4 pain items listed on the FADI, which are given scores ranging from 0 (no pain at all) to 4 (unbearable). Hale and Hertel 13 conducted a study examining the intersession reliability during 1 and 6 week intervals, the sensitivity to differences between healthy participants and participants with CAI, and the sensitivity to changes in function in those with CAI after rehabilitation, of the FADI and FADI Sport. Fifty recreationally active participants 16

completed the FADI and FADI Sport in three different testing sessions: week 1, week 2, and week 7. Each participant completed a separate survey for their limb with CAI and their uninvolved limb. During the study one group of participants was included into a 4- week ankle rehabilitation program, to assess the changes in function after a rehabilitation program. ICC was calculated comparing weeks 1 and 2, and weeks 1 and 7. The researchers found ICC values at week 1 were 0.89 and 0.84 and over 6 weeks at 0.92 and 0.93 for the FADI and FADI Sport, for the involved limbs. Both survey s scores were significantly less for the involved limbs of participants with CAI when compared to their uninvolved limbs. Both the FADI and FADI Sport appear to be valuable tools in assessing subjective deficits in ankle function. The use of self-reported function instruments such as these can be an invaluable and reliable tool in a clinical setting. 13 Both are cost-effective and allow a clinician to make a more informed return-to-play decision regarding ankle injuries and ankle instability. 17

Chapter 3 Methods Study Design This study used a case-control design. Participants Participants were primarily recruited from The University of Toledo intercollegiate athletics. Prior to participation in the study all participants read and signed an informed consent form approved by the University of Toledo Institutional Review Board. Participants within the ankle sprain group were included if they were over 18 years of age, presented with an acute LAS that resulted in swelling, pain, and temporary loss of function within 36 hours of the initial injury, and had no other lower extremity injury in the prior six months. Participants were excluded from the study if they had a vestibular disorder or previous history of fractures or surgery to their ankles. As this was part of a larger study assessing aspects of central nervous system excitability, additional exclusion criteria included a concussion or head injury in the past 6 months, history of a stroke, cardiac condition, cancer in the thigh musculature, cardiac pacemaker, implanted cardiac defibrillator or were currently pregnant/breast feeding. Healthy controls had no previous injury to the ankle, knee, or hip and were recruited following enrollment of an acute LAS participant. The limb of the control participants was matched to the injured limb of the LAS participants. If the LAS 18

participant was afflicted on the right side, then the healthy control performed all assessments on the right side. This was done to avoid any issues of unmatched comparisons of limb dominance that could occur with the randomization of limb assignment in the healthy control group. Procedures All participants were asked to report for a total of five tests sessions done at 36 hours, 5, 7, 10, and 14 days following initial injury or enrollment in the case of the healthy control group. Each testing session lasted approximately 1 hour, with selfreported disability, function and pain assessed using the FADI, FADI Sport and VAS. Dynamic balance was assessed using the SEBT. Ankle girth was measured using the figure-of-eight method. 25 Dorsiflexion range of motion was assessed using a goniometer. Frequency of rehabilitative exercises, athletic participation and use of therapeutic modalities was collected using a treatment questionnaire. Foot and Ankle Disability Index All participants completed the Foot and Ankle Disability Index (FADI) and the FADI Sport at each session. These measurements provided us with knowledge of any presence of subjective disability related to ankle instability. Of the 32 items on the questionnaire, 26 of them are related to deficits in participants activities of daily living and pain. The remaining eight items are related to participation in physical activity. The FADI has a total point value system ranging from 0-104, while the FADI Sport is scored from 0-32. Both the FADI and FADI Sport are converted separately to percentages of disability, with 100% representing no dysfunction at all. 19

Star Excursion Balance Test The directions utilized within this study were anterior, posteromedial, and posterolateral. One and a half inch tape (Johnson & Johnson white porous Coach tape, Skillman, NJ) was utilized to make a testing grid. The anterior reach direction required the participants to place the great toe in the middle of the testing grid. The posteromedial and posterolateral reach directions both required the participants to place their heels in the center of the testing grid. While keeping their hands on their hips and stance heel in contact with the floor, they reached as far as they could with their non-stance foot. When maximal distance was achieved, each participant was instructed to lightly tap his/her foot on the tape grid with the most distal part of his/her foot, and then return the reaching limb back to the center of the testing grid without shifting weight or losing balance. When the participant lightly tapped the tape grid the researcher made a mark on the tape to record the distance achieved. If the participant is judged to have made a heavy contact with the ground and tape grid, shift his/her weight on the stance leg, have his/her heel come off of the ground, remove his/her hands from their waist, or touch the ground with his/her reaching limb while returning back to the center of the grid, the trial was discarded and then repeated. Verbal or visual encouragement was not given to any of the participants during testing. Prior to the measurements beginning, the primary investigator demonstrated each reach direction. The participants were given four practice trials in each reach direction. 40 The participants performed three test trials in each direction in order for an average measurement to be taken. To compare performances between participants, reach distances were normalized to each participants leg length. 42 This is done by measuring 20

from the anterosuperior iliac spine to the medial malleolus, and correlating leg length to reach performance. 42 Researchers have concluded that because of limb length discrepancies, performance differences between participants can be negated through this normalization process. After normalizing the reach distances, performance is expressed as a percentage of limb length. Visual Analog Scale Participants were given a paper with two, 10cm lines each titled differently for pain or ankle function (Appendix E). The lines are meant to act as a scale to allow the participant to subjectively grade his/her own pain level and self-reported ankle function. With respect to the grading system, the far left being very low and the far right being very high, the participants were asked to make a single vertical mark on each line, indicating how they felt relative to each category, at that point in time. A millimeter tape measure was used to measure where each participant marked on the scale. The measurement was then converted to a score ranging from 0-100, according to where the participant marked on the scale. Treatment Questionnaire Participants were given a questionnaire related to treatment strategies done for their acute lateral ankle sprain. Treatment strategies included within the questions are medication use, therapeutic modalities, frequency of therapeutic exercise, and frequency of sport related participation including practice and games. Additionally, they were asked to rate their own overall global function on a percentage scale of 0-100% functional as limited by the injured ankle. 21

Ankle Girth and Dorsiflexion Range of Motion Participants were asked to sit on a treatment table within the athletic training room at the University of Toledo with their knees extended and feet and ankles hanging off of the table. The examiner performed the figure-of-eight measurement method for ankle girth with the ankle positioned in a neutral position. 47 Three consecutive active measurements were performed for an average to be attained for each ankle. The goniometer was placed on the lateral aspect of the ankle joint, with the fulcrum placed on the lateral malleolus to make a 90 angle between the stationary arm and movement arm. The stationary arm was placed parallel along the longitudinal axis of the fibula, while the movement arm was placed parallel along the fifth ray of the lateral aspect of the foot. With the patient in a neutral, 90, the examiner asked the patient to actively dorsiflex to end range of motion. Then the examiner performed three consecutive active dorsiflexion range of motion measurements and an average was calculated for each ankle. Participants returned to a resting position in between each of the three trials. Statistical Analysis For each of the included outcome measures, a 2x5 repeated measures ANOVA was used to determine if differences exist between groups over the selected time points. Tukey s post hoc testing was used in the event of significant interactions. Effect sizes using Cohen s d from the pooled standard deviations were employed to further explore these parametric differences. Participants were excluded from analysis at time points they did not report for testing. All statistical analyses were performed using SPSS 19.0 (SPSS inc., Chicago, IL) statistical software package. Statistical significance was set a priori at P<0.05. 22

Chapter 4 Results Self-Reported Measures For the FADI, a significant interaction for time and group was observed (P<0.001, Table 2). Post-hoc testing revealed that the LAS group had significantly more self-reported disability during ADL s compared to the control group at 36 hours (P<0.001), 5 days (P=0.001), 7 days (P=0.005), 10 days (P=0.001), and 14 days (P=0.001). For the FADI Sport, a significant interaction effect (P<0.001, Table 3) was also observed. Post-hoc testing revealed greater disability during sports and physical activity in the LAS group compared to the control group at 36 hours (P<0.001), 5 days (P<0.001), 7 days (P=0.002), 10 days (P<0.001), and 14 days (P=0.002). For the VAS Pain scale, a significant interaction effect (P<0.001, Table 4) was observed. Post-hoc testing revealed that LAS group had more pain compared to the control group at 36 hours (P<0.001), 5 days (P<0.001), 7 days (P=0.001), 10 days (P=0.002), and 14 days (P=0.003). For the VAS Function scale, a significant interaction effect (P<0.001, Table 5) was demonstrated. Post-hoc testing revealed decreased function in the LAS group compared to the control group at 36 hours (P<0.001), 5 days (P<0.001), 7 days (P=0.001), 10 days (P<0.001), and 14 days (P=0.026). Lastly, for Global Function a significant interaction effect (P<0.001, Table 6) was also demonstrated. Post-hoc testing revealed less Global Function in the LAS group compared to the Control group at 36 23

hours (P<0.001), 5 days (P<0.001) 7 days (P=0.002), 10 days (P<0.001), and 14 days (P<0.001). Dorsiflexion and Ankle Girth Measures Musculoskeletal measures of DF and girth measurements of swelling are presented in Table 7 and 8. For the DF measures a significant interaction effect (P<0.001) was found. Post-hoc testing revealed less DF range of motion in the LAS group compared to the control group at 36 hours (P<0.001) and 7 days (P=0.037). No statistically significant differences were observed at 5 days (P=0.061), 10 days (P=0.714), and 14 days (P=0.145). Although no significant differences were see at days 5, 10, and 14, moderate effect sizes indicated decreased DF range of motion at 36 hours (d= -1.19, 95%CI: -1.90,-0.42), 5 days (d = -0.77, 95%CI: -1.46,-0.04), and 7 days (d= - 0.51, 95%CI: -1.20,0.19). For the Figure 8 Girth Measurement no significant interaction effect (P=0.132) was found. While no statistically significant differences were observed in the ankle girth measurements, a moderate effect size indicated increased ankle swelling in the LAS group at day 14 (d = -0.41, 95%CI: -1.10,0.31) (Table 13). Dynamic Postural Control Measures Average reach distances for the SEBT are reported in Tables 9-11. For the anterior reach of the SEBT no significant interaction effect (P=0.125), main effect for group (P=0.220), or main effect for time (P=0.092) was found. While no statistically significant differences were observed in the anterior reach, moderate effect sizes indicated reduced postural control at 36 hours (d = -0.59, 95%CI: -1.31,0.16), 5 days (d = -0.45, 95%CI: -1.17,0.29), and 7 days (d = -0.64, 95%CI: -1.36,0.12) post injury (Table 24

15). In the posteromedial reach direction of the SEBT a significant main effect for time (P=0.028) was found. No significant main effect for group (P=0.05) or interaction effect (P=0.172) was found. Post hoc testing revealed, for the posteromedial reach of the SEBT, significant differences in 36 hours-7 days (P=0.015), 36 hours-10 days (P=0.009) and 36 hours-14 days (P=0.011). While no statistically significant interaction effect was seen in posteromedial reach distance, a strong-to-moderate effect size indicated reduced postural control at 36 hours (d= -0.97, 95%CI: -1.70,-0.18), 5 days (d= -0.80, 95%CI: -1.53,- 0.03), 7 days (d= -0.43, 95%CI: -1.15,0.31), 10 days (d= -0.58, 95%CI: -1.30,0.17), and 14 days (d= -0.64, 95%CI: -1.36,0.12) (Table 15). In the posterolateral reach direction of the SEBT a significant main effect for time (P<0.001). No main effect for group (P=0.265) or interaction effect (P=0.464) was found. Significant main effects for time were observed, indicating both groups improved when comparing 36 hours-5 days (P=0.019), 36 hours-7 days (P=0.003), 36 hours-10 days (P=0.009) and 36 hours-14 days (P=0.001). While no statistically significant differences were observed in the posterolateral reach, moderate effect sizes indicated reduced postural control at 36 hours (d = -0.51, 95%CI: -1.23,0.24), 5 days (d = -0.40, 95%CI: -1.11,0.34), and 7 days (d = - 0.52, 95% CI: -1.24,0.23) compared to the control group (Table 15). 25

Chapter 5 Discussion We conducted this study to determine the effects of an acute lateral ankle sprain on self-reported function, disability and pain, as well as joint effusion, DF range of motion, and dynamic stability over a 14 day period following injury compared to healthy matched controls. In the ankle sprain group, all self-reported outcomes were negatively affected throughout the 14 days post injury, indicating that perceived functional ability may be significantly decreased longer than two weeks past the time of injury. Concurrent results were observed in measures of dynamic stability, as significant deficiencies were seen in the injured group 14 days post injury. Dorsiflexion range of motion measurements were significantly decreased all the way to 7 days after the initial sprain. After one week, range of motion deficits improved within the injured group. Swelling within the affected ankle in the injured group lasted until 10 days after injury. Our results are unique because self-reported function, self-reported pain, DF ROM, ankle girth, and dynamic stability have not been tracked after acute ankle sprains over a 14 day period. If we know when self-reported measures, ROM, girth, and dynamic stability return to a normal, healthy state, we can clinically advance patients back to activity in a safer manner. Doing so may help avoid further episodes of ankle instability. Self-Reported Measures There were significant differences in self-reported function and disability between the LAS and control groups at each time point. Within our results, each self-reported 26

outcome gradually improved throughout a two week period post-injury. However, the LAS group means did not return to a level of function equivalent to those of healthy participants. Rehabilitation protocols being utilized with participants in our study may not have been addressing self-reported outcomes to the extent needed. Following a LAS many individuals return to full participation within a two week time frame, theoretically with little to no residual side-effects. However, residual symptoms may be present due to inadequate return-to-play protocols allowing athletes to return to play with less that 100% of functional ability, when compared to prior injury status. Most ankle sprains are not seen as severe injuries, which can cause improper management of them and result in the development of chronic ankle instability (CAI). 6 It has been reported that residual symptoms are seen in 40-50% of individuals who suffer from at least one ankle sprain. 3, 7 With our best predictor of CAI being a history of one lateral ankle sprain, 6, 9-11 indicating that clinicians may often underestimate the severity of an athlete acquiring an ankle sprain. If clinicians are returning patients to sport or work participation while residual symptoms are present they may be putting the patient at risk for CAI and further injury. Current treatment strategies and rehabilitation protocols may be ineffective at preventing residual, lasting symptoms that lead to the onset of CAI. 6 Residual dysfunction could present as deficiencies in dynamic stability 6, dorsiflexion (DF) range of motion 16, selfreported function, and strength. 6 This may be a defining factor as to why recurrent ankle sprains are so prevalent. The ability to quantify self-reported function and disability is an invaluable resource clinicians can use to track progress through a rehabilitation program. Subjective reports of function completed by patients are becoming an essential part of clinical 27