FACTORS ASSOCIATED WITH RECURRENT ANTERIOR CRUCIATE LIGAMENT RUPTURES IN FEMALE INTERCOLLEGIATE SOCCER PLAYERS A Thesis Presented to the faculty of the Department of Kinesiology California State University, Sacramento Submitted in partial satisfaction of the requirements for the degree of MASTER OF SCIENCE in Kinesiology (Movement Studies) by Elizabeth Ann Silva SUMMER 2012 © 2012 Elizabeth Ann Silva ALL RIGHTS RESERVED ii FACTORS ASSOCIATED WITH RECURRENT ANTERIOR CRUCIATE LIGAMENT RUPTURES IN FEMALE INTERCOLLEGIATE SOCCER PLAYERS A Thesis by Elizabeth Ann Silva Approved by: __________________________________, Committee Chair Dr. David Mandeville __________________________________, Second Reader Heather Farwig ____________________________ Date iii Student: Elizabeth Ann Silva I certify that this student has met the requirements for format contained in the University format manual, and that this thesis is suitable for shelving in the Library and credit is to be awarded for the thesis. __________________________, Graduate Coordinator Dr. Michael Wright Department of Kinesiology iv ___________________ Date Abstract of FACTORS ASSOCIATED WITH RECURRENT ANTERIOR CRUCIATE LIGAMENT RUPTURES IN FEMALE INTERCOLLEGIATE SOCCER PLAYERS by Elizabeth Ann Silva Statement of Problem Currently all information pertaining to recurrent Anterior Cruciate Ligament (ACL) ruptures has been reported regarding the general female population. This study looked at the female soccer intercollegiate population and factors associated with recurrent ACL ruptures. Sources of Data Data for this study was attained using a non-validated survey using Surveymonkey.com. This website was the most practical method for the type of information being attained while allowing anonymity of all participants. The NATA provided email directories of ATCs in the United States. This free directory was retrieved once the survey request from was approved by the NATA Survey Dispersal and the CSUS Human Subjects Committee. A contact list request form was found on the NATA v website. A disclaimer created by the NATA was attached to the survey to relinquish any endorsement of the NATA. Once all steps had been performed to allow for survey dispersal, 1000 female and male ATCs were selected at random from the NATA contact list. The survey was electronically sent to the subjects through the online survey methods. Conclusions Reached The purpose of this study was to determine the factors associated with the ACL recurrence phenomenon. Both graft type and rehabilitation type were not found to be associated with time to ACL recurrence. Autograft trended towards increased survivorship as did traditional rehabilitation. Future studies are needed to determine the optimal conditions of the initial ACL reconstruction and rehabilitation in order to avoid recurrence for female intercollegiate soccer players. _______________________, Committee Chair Dr. David Mandeville _______________________ Date vi DEDICATION I would like to dedicate this thesis to my parents, Manuel and Alda Silva. They have always believed in me and told me that anything was possible with a hard work. I am thankful for their love and support through all these years of my educational journey. vii ACKNOWLEDGEMENTS I would like to acknowledge my brother-in-law and sister Gilbert and Lucy Gutierrez and my boyfriend Andrew Melo, who have always supported me through the good times and bad. They listened to me complain and cry, but has always pushed me to keep going. I love you always. To Heather Farwig, my reader, my friend, my mentor, you motivate me to keep going and to be a better person and better athletic trainer. I appreciate you helping me through this process and for always believing in me. Thank you for always being there for me educationally and personally. Dr. Mandeville, thank you for sticking with me through this process. I know it took a while and many revisions, but I finally finished. I really appreciate all that you have done. Dr. Wright, thank you for always meeting with me to help me with scheduling and finalizing my thesis. You have helped me in more ways than I can ever imagine. viii TABLE OF CONTENTS Page Dedication .............................................................................................................................. vii Acknowledgments................................................................................................................. viii List of Tables ........................................................................................................................... xi List of Figures ........................................................................................................................ xii Chapter 1. INTRODUCTION .............................................................................................................. 1 Statement of Purpose ................................................................................................... 2 Significance of the Study ............................................................................................ 2 Definition of Terms ..................................................................................................... 2 Delimitations................................................................................................................ 3 Limitations ................................................................................................................... 4 Assumptions................................................................................................................. 4 Hypotheses ................................................................................................................... 4 2. REVIEW OF LITERATURE ............................................................................................. 5 The Anterior Cruciate Ligament .................................................................................. 5 How the ACL is Injured................................................................................................ 6 Factors that Predispose an Increase in Prevalence in ACL Ruptures .......................... 6 Females Soccer Athletes at Risk for Composite Knee Injuries ................................... 8 Forces that Cause Composite Injures ........................................................................... 9 Surgery Options/Graft Selections ............................................................................... 10 Return to Play (RTP) ................................................................................................. 11 Rate of Recurrent ACL Ruptures ............................................................................... 12 Consequences of Recurrent ACL Rupture ................................................................. 13 Purpose....................................................................................................................... 15 3. METHODOLOGY ............................................................................................................ 16 Subjects ...................................................................................................................... 16 Procedures.................................................................................................................. 16 Data Acquisition ........................................................................................................ 17 ix Data Analysis ............................................................................................................. 18 4. RESULTS ......................................................................................................................... 19 5. DISCUSSION .................................................................................................................... 22 ACL Graft Type ......................................................................................................... 22 Rehabilitation Type.................................................................................................... 23 Interpretation.............................................................................................................. 24 Limitations & Future Research .................................................................................. 25 Conclusion ................................................................................................................. 26 Appendix A. Survey: Demographics, First ACL Rupture, Second ACL Rupture ................ 28 Appendix B. Guidelines and Packet for NATA Survey Distribution .................................... 34 Appendix C. Contact Cover Letter for Survey ...................................................................... 41 References ............................................................................................................................... 43 x LIST OF TABLES Tables 1. Page Table 1 Contingency table of the association of ACL graft type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players ........... 20 2. Table 2 Contingency table for the association of rehabilitation type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players ........... 21 xi LIST OF FIGURES Figures 1. Page Figure 1 The association of ACL graft type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players ....................................................... 20 2. Figure 2 The association of rehabilitation type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players ..................................... 21 xii 1 CHAPTER 1 Introduction Soccer is a well-known sport throughout the world. This sport, like many other sports, suffers injuries. A prevalent injury among those athletes is injury to the anterior cruciate ligament (ACL). Females have a four to six time’s higher ACL injury rate when compared to their male counterparts while participating in soccer (Walden, Jagglund, Werner & Ekstrand, 2010). Injury to the ACL in females has many different factors and of those factors the most predominate, ones are anatomical and biomechanical. Anatomical and biomechanical factors vary from a narrow intercondylar notch, Q-angle, valgus force on the knee and ACL ligament size. Once the athlete suffers an ACL rupture, they have to make a choice whether to continue to play or quit. Athletes that continue to play at a high/competitive level typically decided to have surgery. Once a patient has ACL surgery and they go through the rehabilitation phase of recovery. Even with a successful rehabilitation, there is still a chance that they will rerupture their ACL. Some factors associated with this recurrence are ACL graft selection and the type of rehabilitation the athlete goes through. A study performed by Wright, Magnussen, Dunn and Spindler in 2011, showed that females have a two to six percent chance that their ACL graft will have a recurrence of rupture. This statistic is in regards to the general female population and not specific to intercollegiate female soccer players that have a recurrence rate. At this time, there are no studies or statistics reported that are in regards to the ACL recurrence rate of female intercollegiate soccer players. 2 Statement of Purpose The purpose of this study was to assess factors associated with recurrent ACL ruptures in female intercollegiate soccer players. Significance of the Study Most information regarding factors related to ACL recurrence has been reported in regards to the general female population. This is due in part to the fact that factors associated with recurrent ACL ruptures in female intercollegiate soccer players has not been reported. The results of the survey created will help to determine these common factors. Definition of Terms Allograft- a graft of tissue between individuals of the same species but of disparate genotype (Dorland's illustrated medical, 1990). Anterior Cruciate Ligament- a ligament in the knee that attaches to the anterior aspect of the tibial plateau, restricting anterior movement of the tibia on the femur (France, 2011) Autograft- a graft of tissue derived from another site in or on the body of the organism receiving it (Dorland's illustrated medical, 1990). Certified Athletic Trainer (ATC) – a professional who has attained a standard level of competence in athletic training. The ATC is involved in the prevention, recognition, and evaluation of injuries, and works closely with others in rehabilitation from injuries. They have fulfilled the requirements for certification established by the National Athletic Trainers’ Association Board of Certification, Inc. (NATABOC) (France, 2011) Contralateral-On the other side (Prentice, 2011) 3 Intercondylar notch-situated between two condyles (Dorland's illustrated medical, 1990). Ipsilateral- situated on the same side (Prentice, 2011) Lateral Collateral Ligament- a ligament that attaches to the femur and he fibula; maintains stability of the lateral aspect of the knee joint (France, 2011) Medial Collateral Ligament- a flat longitudinal band found on the medial (inside) side of the knee (France, 2011) Posterior Cruciate Ligament- a ligament in the knee that attaches to the posterior aspect of the tibial plateau, restricting posterior movement of the tibia on the femur (France, 2011) Q-angle- is the relationship of the hip to the knee. A line from the superior iliac spine of the hip to the mid patella forms this angle; then an imaginary line is drawn from the middle patella to the tibial tubercle. The space between the two is known as the Q-angle (Prentice, 2011) Valgus- outward bending or twisting force (France, 2011) Varus- inward bending or twisting force (France, 2011) Delimitations This study was delimitated to certified athletic trainers from all divisions of women’s intercollegiate soccer. All subjects were Certified Athletic Trainers (ATC) from all divisions of women’s intercollegiate soccer. All data acquired will be from female intercollegiate soccer players that had a recurrent ACL from fall 2005 to spring 2012. 4 Limitations This study was limited to ATC’s in the United States with colleges that have intercollegiate women’s soccer programs. Only from female intercollegiate soccer, players that have had a recurrent ACL rupture will be used for this study. The validity of the testing instrument (non-standardized survey) and the limited answers provided for the subjects also provided limitations to this study. Assumptions It was assumed that all participants would understand and answer honestly questions stated in the survey used for this research. It was assumed that all participants were ATC’s that had access to records pertaining information regarding female intercollegiate soccer players that suffered two ACL ruptures and were familiar with the survey engine . Hypotheses The following hypotheses were investigated: 1. It is predicted that there will be significant relationship between female intercollegiate soccer players with a recurrent ACL rupture and accelerated rehabilitation (H1). 2. It is predicted that there will be significant relationship between female intercollegiate soccer players with a recurrent ACL rupture and graft selection (H2). 5 CHAPTER 2 Review of Literature The Anterior Cruciate Ligament (ACL) is a vital part of knee stability that is located inside the knee within the intercondylar notch (Prentice, 2011). A highly active athlete such as one that plays soccer needs their ACL to aid in the movements needed for soccer such as cutting, pivoting and jumping. Soccer has a high risk to ACL injuries relative to other sports (Alentorn-Geli, Myer, Silvers, Samitier, Romero, Lazaro-Haro & Cugat, 2009). Females have a four to six time’s higher ACL injury rate when compared to their male counterparts (Walden, Jagglund, Werner & Ekstrand, 2010). Some of these factors are due to anatomical and biomechanical factors. Looking at some of these anatomical and biomechanical factors along with graft selection and type of rehabilitation (rehab) will help to determine what factors lead to the phenomenon of recurrent ACL ruptures. The Anterior Cruciate Ligament The ACL is the most injured ligament in the body (Spindler & Wright, 2008). Annually in the U.S., there are approximately 95,000 new ACL ruptures and about 60,000 to 75,000 surgical reconstructions of the ACL (Gammons & Schwarts, 2011). Reconstructive surgery is recommended for individuals that are physically active. The ACL stabilizes the knee during physical activity and is made up of three twisted bands: the anteromedial (AM), intermediate and posterolateral (PL) bands (Prentice, 2011). These bands are interwoven together in the form of a braid for increased tensile strength. Of these three bands, the AM and PL are the most noticeable bands. These 6 bands of the ACL prevent anterior translation of the tibia on the femur so that during activities, the tibiofemoral joint is stabilized. The ACL restricts the tibia against excessive internal rotation and serves as a secondary restraint for valgus and varus stress in the presence of collateral ligament damage (Prentice, 2011). The ACL also works in conjunction with the thigh muscles, specifically the hamstrings, to resist anterior sheer force of the knee joint during physical activities. Without the ACL, a physically active patient will complain of having the sensation of their knee “giving out” or feel unstable which can potentially lead to other knee injuries. How the ACL is Injured A complete rupture of the ACL can occur by contact or non-contact mechanisms. A contact mechanism occurs when either a player is struck by another player or object. This can cause a valgus force or forced hyperextension. Hyperextension occurs when a force great enough is delivered to the front of the knee, which translates the tibia posteriorly and ruptures the ACL. A non-contact injury occurs without direct contact and can be caused when the lower leg is rotated while the foot is fixed. This is typically known as a plant and twist mechanism. Whether the rupture is contact or non-contact, the patient will report hearing and/or feeling a “pop.” Of the two types of mechanisms of injury, the majority of ACL ruptures are non-contact (The MARS Group, 2010). Factors that Predispose an Increase in Prevalence in ACL Ruptures Ninety percent of ACL tears in women and sixty percent in men occur via the non-contact mechanism (Spindler & Wright, 2008). Although the non-contact mechanism is extremely high in females, it is not known what causes the increased 7 prevalence. It has been reported that females have a two to three times higher ACL injury risk compared to men (Walden, Jagglund, Werner, & Ekstrand, 2010). Studies have shown that anatomical factors such as ligament size of the natural ACL and femoral intercondylar notch relate to ACL rupture. Additionally postural, biomechanical, strength and hormonal differences are thought to be risk factors for increased ACL rupture in females (McDaniel, Rasche, Gaudet, & Jackson, 2010) (Foster, 2008) (Prentice, 2011) A narrow intercondylar notch may predispose females to ACL injury. The positioning of the ACL within the notch, and a narrow notch width may cause increased elongation of the ACL under high tension (Hewett, Myer & Ford, 2006). One potential injury occurs when a forced rotation of the femur occurs on the fixed tibia. The forced rotation causes a narrowing of the notch, which then impinges the ACL, possibly leading to rupture of the ligament (Prentice, 2011). A narrower intercondylar notch may also lead to a smaller, weaker ACL. An additional anatomical factor related to increased ACL rupture for females is the Q-angle. The Q-angle is a relationship of the hip to the knee. This angle is formed by a line from the superior iliac spine of the hip to the mid patella; then an imaginary line is drawn from the middle patella to the tibial tubercle. The space between the two is known as the Q-angle. An excessive degree of Q-angle is thought to predispose females to knee injuries. The normal Q-angle for males is ten degrees whereas females it is fifteen degrees. Anything exceeding fifteen degrees is considered excessive and can lead 8 to an increase in ACL rupture (Prentice, 2011). This excessiveness in females is due to the increased hip width that aids in childbirth. Other risk factors for the increased prevalence of ACL rupture in females are biomechanical differences. In females more so than males, a valgus force is placed on the knee during jump landing. This causes an increase in the valgus angle and can lead to increased probability for ACL injuries (Foster, 2008). ACL ligament size in females is typically smaller, thus the increased biomechanical loads during jump landing increase the likelihood of rupturing the ACL (Foster, 2008). All of these factors combined, can lead to the increased stress placed on the ACL in physically active females, which may lead to increased prevalence of ACL ruptures during sports such as soccer. Female Soccer Athletes at Risk for Composite Knee Injuries Females in jumping, cutting, pivoting sports have a four to six times higher ACL injury compared to male counterparts (Walden, Jagglund, Werner & Ekstrand, 2010). Many of these movements are combined in the game of soccer. These movements vary from running, sprinting, jogging, pivoting, shifting, twisting and cutting. In isolation, many of these movements do not cause injury to the ACL, but a combination of these movements may lead to the non-contact mechanism of rupture. However, it is unknown which movements or which position in soccer has an increase in ACL rupture prevalence. It is known that the combinations of movement in soccer cause forces sufficient to cause ACL rupture in females. During soccer, the contact or non-contact mechanism of injury rarely ruptures the ACL in isolation. Typically, an ACL injury is associated with other ligaments, cartilage 9 or bones being injured as well. A strong valgus force along with the rotation of the femur on the tibia causes the medial aspect of the knee to be loaded with enough force to tear the ACL, MCL and medial meniscus. This is known as the unhappy triad. When there is enough valgus force, the MCL is also injured due to the attachment of the MCL to the medial meniscus (Prentice, 2011). The ligament injured in association with the ACL is usually the medial meniscus. This is due to the loading of the femur into the tibia. This load causes the femoral notch to tear the ACL and “pinch” the medial meniscus between the femur and the tibia. Forces that Cause Composite Injuries The mechanism of ACL injury is associated with certain types of forces that can cause other injuries to the knee. Of the forces applied to the knee, there are four that can cause injury to other ligaments of the knee. A valgus force alone can lead to injury of the MCL; a varus force causes injury to the LCL; a force from the anterior (front) aspect of the knee can cause injury to the ACL; and a force from the posterior (back) aspect of the knee can cause a PCL injury along with an ACL injury (Prentice, 2011) These forces can lead to three different degrees of injury to the ligaments. These degrees range from a grade one to a grade three-ligament sprain. A grade three-ligament sprain is when the ligament is completely ruptured. These forces may also lead to damage of other components of the knee, primarily the menisci. Menisci injuries can occur with a plant and twist mechanism or a valgus force. A plant and twist mechanism loads the medial aspect of the knee therefore forcing the femoral condyle to press on the medial meniscus and tearing part of it; or varus force great enough to cause not only the LCL to rupture 10 but also causing the medial femoral condyle to open up and potentially stress the medial meniscus to tear. Once these injuries occur, the next step is to decide whether or not to continue to live life with the injury or have surgery to repair the damage. Those that decide to have surgery are physically active and those that do not live a sedentary life. Surgery Options/Graft Selections Some athletes can opt to not have surgery after a ruptured ACL and can try to rehabilitate their leg. If their muscles are strong enough they may be able to be an active athlete without having their ACL. As long as they do not have the sensation of instability then they can continue with activity. However, orthopedic surgeons recommend that athletes elect surgical reconstruction of the ACL in order to return to their high level of activity. This is due to the fact that if a high-level athlete continues to perform without an ACL, they predispose themselves to possibly injure other joint structures, ligaments or muscles. Once the athlete has decided to have their ACL repaired, there are different options for ACL surgery. The two main types of surgeries performed to repair the ACL are an autograft and an allograft. An autograft is tissue from the athlete themselves to make a graft ACL and an allograft is tissue from a deceased person that donates their body to science. The types of autografts used are bone patellar tendon bone (BPTP) which is where the surgeon takes a piece of the athletes’ patellar tendon with bone plugs on either end or a hamstring graft of the semitendinosus and gracilis muscle. One study showed that bone-patellar tendon-bone for young person’s is the best graft selection and semitendinosus and gracilis for older subjects, women and those devoted to recreational 11 sport (Garofalo, Moretti, Kombot, Moretti, & Mouhsine, 2007). The types of allografts typically used are an achilles tendon of the ankle or posterior tibialis tendon of the ankle. These grafts are frozen and placed in a cadaver bank until they are ready to be used. Once ready to be used they are sized and fitted for the athlete. ACL graft selection is determined by surgeon preference (Battaglia, Cordasco, Hannafin, Rodeo, O’Brien, Altchek, Cavanaugh, Wickiewicz & Warren, 2007). Once surgery has been performed, the athlete then goes through the process of rehabilitation and determining a return to play. Return to Play (RTP) Recovery time of a typical ACL only reconstruction has been reported to take between eight to twelve months (Holgum, 2005). This time frame depends upon the type of rehabilitation. The athlete either goes through an accelerated or traditional rehabilitation. Accelerated rehabilitation is defined as returning to full activity between four to six months (Holgum, 2005). This type of rehabilitation can be used for those in that participate in competitive and/or serious recreational sports. When an athlete participates in an accelerated program, they usually begin early weight bearing. It is believed that there are few complications from the surgery with early weight bearing. Traditional rehabilitation is known as returning to full activity between eight to twelve months (Holgum, 2005). This type of rehabilitation is a delayed program with the same progressions but at a slower rate. Jogging progression to straight running is not permitted until approximately six months whereas in an accelerated program would begin running 12 around the four month mark. During the eight to twelfth month is when the athlete will return to full sport (Holgum, 2005). Whether the athlete goes through an accelerated or a traditional rehabilitation, currently there are no universal RTP criteria. To determine if the athlete is able to RTP, the only assessments used are freedom of pain, normal strength and sport specific exercises (Hetzler, Luke, Bushman, & Hetzler, 2009). These measurements are all determined by each specific athlete. Even after the athlete has returned to normal sporting activity, there is still a chance that they may re-injure their knee. Rate of Recurrent ACL Ruptures Females have a two to six percent chance of ACL graft rupture recurrence after less than five years from the initial reconstruction even in successful rehabilitation traditional or accelerated (Wright, Magnussen, Dunn & Spindler, 2011). Whether the recurrence of the ACL rupture occurs on the contralateral (opposite) leg vs. the ipsilateral (same) leg is approximately three percent (Wright, Magnussen, Dunn, & Spindler, 2011). Previous reports indicate several reasons for graft failure including technical, biological or a combination of both (The MARS Group, 2010). Technical failure refers to as surgical error. This is can occur when the tunnel placement is to anterior/posterior in the femur or tibia. Biological failure was defined as “lack of incorporation of the graft as evidence by early failure without a significant traumatic episode or obvious significant technical problems with the previous reconstruction” (The MARS Group, 2010). The athlete will begin to function and go through rehabilitation, but over a period of time the 13 knee will feel loose or unstable. The most accurate test to perform in order to determine a biological failure is the Lachman’s (Lam, 2011). Another potential reason for failure can be due to decreased sensation of pain. A decreased sensation of pain can lead to the accelerated progression of rehabilitation even though the graft is not at its full strength. This fast progression could cause the graft to rupture. The likelihood of this can be due to the use of an allograft instead of an autograft. In using an allograft athletes often do not have as much pain because the tissue is not from their own body. Common graft failure occurs in an allograft due to early pain free exercises. Because the allograft is a foreign body in the athlete, the nociceptors are diminished which allows the athlete to push forward with exercises. They will not feel the normal amount sensory pain since it does take time for the body to take the allograft to mold and adapt it to their new ACL graft. The bone plugs themselves will take a full year to heal and the ACL graft is at its most vulnerable state in the first couple of months after surgery. Consequences of Recurrent ACL Rupture The effect of the recurrent ACL rupture can negatively impact the career of the female athlete. Due to recurrence of an ACL injury, some females are forced to quit playing soccer. Some reasons forcing the athlete to quite are going through multiple surgeries, increased cost of having multiple surgeries along with rehabilitation after both repairs are made. The athlete may decide to have the ACL repaired both times but might still suffer pain and cannot continue to compete at the level of competition that is needed. For an athlete competing at the intercollegiate level this not only causes physical stress 14 but also mental stress. They have to think not only for the current situation but their future. Another factor impacting the female athlete’s career is the cost of surgical reconstruction of not only the initial rupture but the second one as well. Along with the surgery comes the cost of rehabilitation for the initial a secondary injury. The mean total cost was for a surgical repair of an allograft ACL reconstruction is $5,465 and $4,872 for autograft ACL reconstruction. An allograft ACL reconstruction was more costly than autograft ACL reconstruction in the outpatient setting (Nagda, Altobelli, Bowdry, Brewster & Lombardo, 2010). Some complications may occur after the secondary rupture that leads to a more extensive surgery, which in turn leads to an increased cost of the surgical approach along with extended rehabilitation. The consequences may seem small initially when the female athlete contemplates quitting playing soccer; however their knee function may be compromised in the future. Multiple injuries and surgeries can lead to knee osteoarthritis (OA) and has an early increased probability after ACL reconstruction. It is estimated that OA develops in fifty percent of patients with ACL tears ten to twenty years after the injury (Spindler & Wright, 2008). This can lead to a debilitating joint pain and thus decreases the quality of life and eventually can then lead to a total knee replacement (TKR). What most people do not know is that a TKR is not covered by insurance companies until the patient reaches fifty years of age. 15 Purpose Most information regarding the factors related to ACL recurrence has been reported with reference to the general female population. The factors associated with recurrence in female intercollegiate soccer players have not been previously reported. Specifically the association of graft selection and accelerated rehabilitation factors remain unknown. Therefore the purpose of this study is to assess factors associated with recurrent ACL ruptures in female intercollegiate soccer players. It is predicted that accelerated rehabilitation will be strongly correlated with recurring ACL ruptures and additionally, it is thought that graft selection will be correlated with recurrent ACL ruptures. 16 CHAPTER 3 Methodology This study was designed to determine the factors that are associated with the phenomenon of recurring ACL ruptures in female collegiate soccer players. It is hoped that this information will help future athletes avoid recurrent ACL ruptures. Subjects The subject sample is comprised of Certified Athletic Trainers (ATC), who will provide information regarding female intercollegiate soccer players with recurrent ACL ruptures in their care. Those that will be included are ATC from NCAA division I, II & III, NAIA and junior colleges of women’s collegiate soccer. Those that were excluded are colleges that do not have a women’s collegiate soccer program. Procedures A non-validated questionnaire created by the researcher (see Appendix A) was used to gather data. The validity and reliability of this survey has not been established but this type of survey has been previously used and is the most appropriate method to acquire this type of ACL re-injury data. The survey was created so as to minimize the responses and elicited data pertaining to recurrent ACL injuries in the female collegiate soccer players. The survey was sent to the National Athletic Trainer’s Association (NATA) secretary for distribution. The ATC subjects completed the self-reported multiple-choice questionnaire after accepting the informed consent that at the beginning of the survey which has been reviewed and approved by the California State University, Sacramento Internal Review Board (IRB). 17 A 19 questionnaire was created and disbursed with four sections of questions. The first section of the survey addressed background information of the ATC regarding the level of women’s soccer which they work at and if they have access to the information needed for the survey. The second section of the survey regards information concerning the athlete’s first ACL rupture. Questions begin with the athlete’s demographics such as age, height and weight and then questions such as their mechanism of injury (MOI), and all information regarding their initial ACL rupture. The third section of the survey is designed to acquire information regarding the second ACL rupture. Data Acquisition The survey was created using Surveymonkey.com. This website was the most practical method for the type of information being attained while allowing anonymity of all participants. The NATA provided email directories of ATCs in the United States. This free directory was retrieved once the survey request from was approved by the NATA Survey Dispersal (see Appendix B) and the CSUS Human Subjects Committee. A contact list request form was found on the NATA website. A disclaimer created by the NATA was attached to the survey to relinquish any endorsement of the NATA (see Appendix B). Once all steps had been performed to allow for survey dispersal, 1000 female and male ATCs were selected at random from the NATA contact list. The survey was electronically sent to the subjects through the online survey methods. The timeline for this survey was dispersal on March 28, 2012 with final collection in April 14, 2012. If 18 there were not enough participants, then a follow up e-mail would be sent to the participants not having completed the survey. After this e-mail is sent, then the survey would remain open until April 20, 2012. Data Analysis Correlation analysis will be used to analyze the relationships between graft rupture factors and ACL recurrence using Chi Square (p<0.05, SPSS Chicago, IL). 19 CHAPTER 4 Results The response rate of this study was 19.7%, with one hundred and ninety seven surveys answered. Of those, twenty responded having had an ACL recurrence. Of those twenty, sixteen reported contralateral ACL rupture (80%) and four reported ipsilateral ACL recurrence (20%). As this study aimed to assess the factors associated with recurrent ACL ruptures, only the ipsilateral respondents were assessed. Thus four subjects were used to evaluate associations between ACL graft type to time of recurrence and rehabilitation type to time of recurrence. The responses were grouped into three variables, ACL graft type, rehabilitation type, and time to recurrence. The ACL graft variable was categorized as: autograft (category 1, bone-patellar tendon-bone and hamstring,) and allograft (category 2, cadaver connective tissue). The second variable was rehabilitation type: traditional rehabilitation (category 1, 8-12 months), and accelerated rehabilitation (category 2, 4-6 months). The third variable, time to recurrence was categorized as being: date of initial rupture to date of recurrence less than 12 months (category 1), or greater than 12 months (category 2). The results indicated that the predominate graft type was autograft (n = 3) and rehabilitation type was traditional rehabilitation (n = 3, Tables 1 & 2, Figures 1 & 2). Associations between the variables were assessed using a Chi Square (x2, p < 0.05). For this test at p = .05, the critical value for significance was x2 = 3.841. The association between graft type and time to recurrence was found to be not significant (x2 = 0.53). The association between rehabilitation type and time to recurrence was found to be not significant (x2 = 0.53). 20 Table 1. Contingency table of the association of ACL graft type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players. a b Graft Time to type recurrence Category 1a 3 2 Category 2b 1 2 Totals 4 4 Category 1 = Autograft; Category 2 = Allograft Category 1 = less than 1 year; Category 2 = greater than 1 year x2= 0.53, non-significant x2= 0.53, non-significant Figure 1. The association of ACL graft type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players. 21 Table 2. Contingency table for the association of rehabilitation type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players. Rehabilitation Time to type recurrence Category 1a 3 2 Category 2b 1 2 Totals 4 4 a Category 1 = Traditional Rehabilitation; Category 2 = Accelerated Rehabilitation b Category 1 = less than 1 year; Category 2 = greater than 1 year x2= 0.53, non-significant x2= 0.53, non-significant Figure 2. The association of rehabilitation type and time to ipsilateral ACL recurrence of four intercollegiate women soccer players. 22 CHAPTER 5 Discussion Most information pertaining to the factors related to ACL recurrence for non-athletic female population has been reported with reference to the general male population. Researchers do suggest that future studies should focus on factors related to ACL recurrence within the female population (Foster, 2008). Currently, these factors have not been reported for female intercollegiate soccer players. This area of study needs to be researched due to the fact that females involved in cutting, jumping and pivoting sports have a four to six times higher ACL injury rate compared to their males counterparts (Walden, Jagglund, Werner, & Ekstrand, 2010). The purpose of this study was to determine if the type of rehabilitation and the type of ACL graft were associated with time to ACL recurrence. It was predicted that there would be a significant relationship between accelerated rehabilitation and time to ACL recurrence for female intercollegiate soccer players (H1). Additionally, a significant relationship was predicted between graft type and time to ACL recurrence for female intercollegiate soccer players (H2). Information gained from this study could be used to influence female intercollegiate soccer players along with other sports medicine professionals in their selection of graft and rehabilitation type in order to avoid ACL recurrence. ACL Graft Type The American Board of Orthopaedic Surgery lists ACL reconstructions as the sixth most common procedure performed (Nagda, Altobelli, Bowdry, Brewster, & Lombardo, 2010). Prior to these surgeries, the surgeon has the choice in determining the 23 type of ACL graft used (Battaglia, Cordasco, Hannafin, Rodeo, O’Brien, Altchek, Cavanaugh & Wickiewicz, 2007). The graft type associated with increased survivorship for ACL reconstruction continues to be an area of debate (The MARS Group, 2010). The two types of ACL grafts primarily used for reconstruction are allograft (cadaver) and autograft (hamstring tendon and bone-patellar tendon-bone). After the reconstruction is performed, the ACL graft has to incorporate into the body allowing for full function of the athlete. A study performed by Kaeding et. al., (2010) showed that allograft rupture rates were higher than autograft ruptures in patients 10 to 19 years of age. Thus, the type of ACL graft used may influence ACL recurrence rates; therefore this variable was used in this study. Rehabilitation Type There is no universally utilized return to play (RTP) criteria for individuals returning from ACL reconstruction (Hetzler, Luke, Bushman & Hetzler, 2009). The most common measurements used for RTP are: freedom of pain, range of motion, normal strength, proprioception and sports specific functionality (Hetzler, Luke, Bushman, & Hetzler, 2009). These attributes are measured while the athlete transitions through their respective physical therapy program. The two types of physical therapy programs are traditional rehabilitation (returning to sport within eight to twelve months) and accelerated rehabilitation (returning to sport within four to six months). Athletes participating in traditional rehabilitation begin running at a later time period (approximately month six) compared to those that are participating in accelerated rehabilitation (approximately month four, Holgum, 2005). Often, athletes that participate 24 in intercollegiate sports participate in the accelerated rehabilitation program. It may be likely that in athletes returning to play too soon, the ACL graft has not had the time to incorporate into the body, which can cause graft failure. However, it is unknown if rehabilitation type influences ACL recurrence rates. Interpretation Graft type was not found to be associated with time to ACL recurrence. Of the two types of ACL grafts in this study, autograft was the predominate graft of the four subjects (n = 3). This finding was unexpected as autograft incurs secondary surgical trauma at the graft site. Despite this fact, surgeons chose autografts for these athletes possibly due to the higher survival rate when compared to allograft. In this study one subject with an autograft suffered ACL recurrence within a year which was similar to the one subject with an allograft. The remaining two autograft subjects had recurrence greater than one year. Based on these findings autograft appears to have increased survivorship. Future studies are needed to substantiate these findings. Rehabilitation type was not found to be associated with time to ACL recurrence. Interestingly, of the two rehabilitation types studied, traditional rehabilitation was the predominate type of the four subjects (n = 3). This was unexpected because it was thought that athletes at the intercollegiate level would go through an accelerated rehabilitation program in order to compete for their position on the team. The choice of rehabilitation program that the athlete goes through is the surgeon’s, in consultation with either the physical therapist or ATC. It may be that surgeon’s choice the conservative rehabilitation type in order to increase graft survivorship. However, the one subject with 25 accelerated rehabilitation experienced an ACL recurrence within a year, as did one subject with traditional rehabilitation. The remaining two subjects that went through traditional rehabilitation had an ACL recurrence greater than one year. Although these findings are inconclusive, traditional rehabilitation appears to have increased ACL survivorship. Limitations & Future Research This study was limited to ATC’s in the United States with colleges and universities that had intercollegiate women’s soccer programs. Only data pertaining to female intercollegiate soccer players that have had a recurrent ipsilateral ACL rupture were used in this study. These specific parameters may have limited the sample size. It is likely that the limited sample size was not sufficient to power the study to avoid type II error. Although the findings of this study are limited by a small sample, this area requires additional research involving increased sample sizes. as studies have shown that fifty percent of ACL injuries occur to individuals between the ages of 15-25 (Lam, 2011). Of the survey data collected, sixteen ATC respondents had information pertaining to female intercollegiate soccer players that had a second ACL rupture of the contralateral knee. Future research could be expanded to include these female athletes having suffered a second ACL rupture. If this direction is taken, then rehabilitation type on the involved side would have to be linked to the contralateral rupture. It is more likely that anatomical and biomechanical factors would influence a contralateral rupture. Additionally, because females in cutting, jumping and pivoting sports have a four to six times higher ACL injury rate compared to their male counterparts, future studies could be 26 broadened to involve other female sports that use these movements (Walden, Jagglund, Werner, & Ekstrand, 2010). Conclusion The purpose of this study was to determine the factors associated with the ACL recurrence phenomenon. Both graft type and rehabilitation type were not found to be associated with time to ACL recurrence. Autograft trended towards increased survivorship as did traditional rehabilitation. Future studies are needed to determine the optimal conditions of the initial ACL reconstruction and rehabilitation in order to avoid recurrence for female intercollegiate soccer players. 27 APPENDICES 28 APPENDIX A Survey: Demographics, First ACL Rupture, Second ACL Rupture 29 Survey Questions 1. Do you have access to medical records from Fall 2009-Spring 2011 regarding female intercollegiate soccer players? Yes No 2. Which level of college do you work at? Division I Division II Division III NAIA Junior College 3. How many recurrent ACL ruptures did you have within the women’s soccer team from Fall 2005-Spring 2011? 4. What was the date of the first rupture? Athlete A_________ C___________ Athlete B___________ Athlete Athlete D___________ F___________ Athlete E ___________ Athlete 5. What were the height, weight & age of each athlete? Athlete A__________ C___________ Athlete B____________ Athlete Athlete D__________ F___________ Athlete E____________ Athlete 6. What was the mechanism of injury of the initial rupture? (Contact vs Noncontact) Contact: Struck by another player or object Non-contact: Self injured Athlete A__________ C___________ Athlete B___________ Athlete Athlete D__________ F___________ Athlete E___________ Athlete 30 7. What did the initial rupture consist of (Check all that apply)? Athlete A ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete B ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete C ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete F ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete E ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete D ____Lateral Meniscus Tear ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear ____Lateral Meniscus Tear 8. Was the athlete on her menses during the initial rupture? (Yes, No, Unknown) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 9. What type of surgical approach was used for the first ACL reconstruction? (Bone-patellar tendon-bone, Cadaver allograft, Hamstring tendon) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 31 10. What type of rehabilitation did the athlete go through? (Traditional or Accelerated) Traditional: returning between 8-9 months Accelerated: returning 4-6 months Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 11. Was the athlete wearing a functional brace after her first reconstruction when she re-injured her ACL? (Yes, No, Unknown) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 12. Was the second rupture ipsilateral or contralateral? Athlete A__________ C___________ Athlete B___________ Athlete Athlete D__________ E___________ Athlete D___________ Athlete 13. What was the date of the second rupture? Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E ___________ Athlete F__________ 14. What were the height, weight & age of each athlete? Athlete A__________ C___________ Athlete B____________ Athlete Athlete D__________ F___________ Athlete E____________ Athlete 15. What was the mechanism of injury of the second rupture? (Contact v Noncontact) Athlete A__________ Athlete B___________ Athlete C__________ 32 Athlete D__________ Athlete E___________ Athlete F__________ 16. What did the second rupture consist of (Check all that apply)? Athlete A ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete B ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete C ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete F ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete E ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear Athlete D ____Lateral Meniscus Tear ____Lateral Meniscus Tear ____ACL tear ____PCL tear ____MCL tear ____LCL tear ____Medial Meniscus Tear ____Lateral Meniscus Tear 17. What type was used for the second ACL reconstruction? (Bone-patellar tendon-bone, Cadaver allograft, Hamstring tendon) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 18. Was the athlete on her menses during the second rupture? (Yes, No, Unknown) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 33 19. What position did the athlete play? (Forward, Midfield, Defense, Goal keeper) Athlete A__________ Athlete B___________ Athlete C__________ Athlete D__________ Athlete E___________ Athlete F__________ 34 APPENDIX B Guidelines and Packet for NATA Survey Distribution 35 NATA NATA guidelines regarding lists for members conducting surveys NATA certified members requesting lists for research purposes will be referred to their district secretary for approval of their project. NATA will provide address lists or email lists for approved research projects by certified members at the lowest rate (9 cents/name) – prepayment and a signed one-time use agreement required. There is no limit to the number of contact names a certified member can request for his/her project. NATA does not offer an email broadcast service for certified members’ research broadcasts. Student members sending up to 1,000 surveys can be done via email: A broadcast to a maximum of 1,000 email addresses can be provided for student members conducting research projects. NATA has the ability to provide a random sample of the population, if it exceeds 1,000. NATA will transmit the cover letter (containing a link to the member's questionnaire) via email to recipients. The transmission will be labeled as coming from the researcher. If a follow-up reminder is desired, NATA will transmit a second letter to the same members selected for the original broadcast. Student member surveys of more than 1,000 will be conducted via U.S. mail: Since email lists are not available in quantities above 1,000, member research that requires a population greater than 1,000 is handled in the following manner. NATA can provide name and address of the population desired so the member can send the hard copy surveys via U.S. mail. The member must sign an agreement indicating the data will be used only one time and only for the stated purpose. NATA will forward the data electronically to the member, who can then print the labels for the mailing. If a follow-up reminder is desired, the member must once again sign a “one time use” agreement for the second mailing. Disclaimer: The NATA Board of Directors has implemented this policy in regards to student surveys: Graduate Student Surveys: When a graduate student asks the national office for a mailing or email list to send a survey, s/he is referred to the relevant district secretary. If the survey meets the District Secretaries/Treasurers Committee’s requirements, the graduate student is given approval to receive a free list. The board was concerned the recipients may think the surveys are NATA-sponsored. The board asked that the graduate students be required to print a disclaimer at the beginning of the questionnaire to alleviate this confusion. This wording was subsequently developed: “This student 75 survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research.” (6/13/02) 36 NOTE: THIS POLICY IS SUBJECT TO CHANGE WITHOUT NOTICE. Only NATA student members may access this service. 37 Guidelines Process: For student members, NATA will broadcast email student surveys to a maximum of 1,000 participants. If a follow-up reminder is desired, NATA will transmit a second letter to the same members selected for the original broadcast. For professional members, NATA will provide address or email lists at the lowest rate (9¢/ name). Prepayment and a signed one-time use agreement are required in addition to the documents below. There is no limit to the number of contact names a professional member can request for a project. NATA does not offer an email broadcast service for professional members. Disclaimer: The following disclaimer is required: “This student survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research.” Requirements: 1. Completed application form (next page). 2. Institutional Review Board approval - upload as part of form. 3. Informed Consent form, if applicable - upload as part of form. 4. Word (.doc) version of survey invitation email to participants - upload as part of form. See Sample Cover-Letter for more information. 5. Description / criteria identifying targeted survey participants - see 'ResearchSurvey-Criteria' document for more information. 38 Survey List Request Form Purpose of Mailing List (check all that apply): _ Email Survey -Email broadcast service by National Office (max. 1000 recipients available to student members only) _ Is follow up Email Survey required? _ Survey (for non students) _ email addresses _ postal addresses File format: _ Comma Delimited Text _ Excel Work Settings: _College/University _Secondary School _Clinic _Hospital _Professional Sports _Industrial/Occupational/Corporate _Business/Sales/Marketing _Heatlh/Fitness/Sports Clubs/ _Performance Enhancement Clinics _Amateur/Recreational/Youth Sports _Military/Law Enforcement/Government _Independent Contractor _Other _Unemployed _ All Member Types _ Certified _ Associate _ Retired Certified _ Certified Students _ Non-certified Students _ International Non-Certified _ Certified International To select by geographical area, please select one: _ US only _ All Districts 39 _ All members (Canada & International included) To make a selection by State or District, check/circle below: Districts States _1 CT, ME, MA, NH, RI, VT _2 DE, NJ, NY, PA _3 DC, MD, NC, SC, VA, WV _4 IL, IN, MI, MN, OH, WI _5 IA, KS, MO, NE, ND, OK, SD _6 AR, TX _7 AZ, CO, NM, UT, WY _8 CA, NV, HI, Guam _9 AL, FL, GA, KY, LA, MS, TN _ 10 AK, ID, MT, OR, WA SURVEY LIST USE AGREEMENT I certify that the requested NATA survey list will be utilized only for the study specified above. The list will not be duplicated, copied, or reproduced in any manner, but used one time only. I agree that any broadcast email will not contain other recipients’ email addresses in the “To:” or “Cc:” field, since the email addresses provided are not to be shared among the recipients. To send a broadcast email from Microsoft Word, we have provided instructions in the members-only section of the NATA Website. Go to: https://cf.nata.org/members1/documents/mass_email_instructions_for_nata.pdf. Members agree to abide by policies and procedures of the NATA. Failure to abide by these requirements is a violation of such policies and may subject the user to sanctions by the NATA Ethics Committee. Applicant Signature________________________ Date ____________________ 40 SAMPLE Contact Cover Letter for student surveys Dear Fellow Certified Athletic Trainer: I am a master’s degree candidate at (University Name), requesting your help to complete part of my degree requirements. Please follow the link at the end of this letter to an online survey titled: (Title of Project). This student survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research. The questionnaire consists of __ demographic questions and __ Likert Scale (1-very uncomfortable to 5 very comfortable) questions, which will take about five to seven minutes to complete. One thousand randomly selected certified NATA members in (Location Demographic) with a listed email address are being asked to submit this questionnaire, but you have the right to choose not to participate. The (University Name) Institutional Review Board has approved this study for the Protection of Human Subjects. This is a completely anonymous questionnaire and upon submission, neither your name nor email address will be attached to your answers. Your information will be kept strictly confidential. As a fellow certified athletic trainer, your knowledge and opinions regarding this topic makes your input invaluable. Please take a few minutes to fill out the anonymous questionnaire you will find by clicking on this link and submit it by (Date): (http:/__________________________________ /) Thank you for your time and consideration. Sincerely, Name of Member and Credentials Institution Name Address Email Address Participants for this survey were selected at random from the NATA membership database according to the selection criteria provided by the student doing the survey. This student survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research. 41 APPENDIX C Contact Cover Letter for Survey 42 Dear Certified Athletic Trainer, I am a master’s degree candidate at California State University, Sacramento requesting your help to complete part of my degree requirements. The purpose of this message is to request your participation in a research investigation designed to look at Factors Associated with Recurrent Anterior Cruciate Ruptures in Female Intercollegiate Soccer Players from Fall 2005 until Spring of 2011. This student survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research. The questionnaire consists of 19 yes/no, check all that apply and demographic questions which should take approximately 20-30 minutes to complete. Participation in this study is entirely voluntary and refusal to participate involves no penalty, neither will harm be placed by taking this survey. As a fellow certified athletic trainer, your knowledge and opinions regarding this topic makes your input invaluable. Please take a few minutes to fill out the anonymous questionnaire and submit it by April 14, 2012. The following link https://www.surveymonkey.com/s/ACL-Silva will direct you to the questionnaire and specific instructions. Strict confidentiality will be maintained throughout this research. If you have any questions, comments, or technical difficulties, please contact me, Elizabeth Silva at (XXX) XXX-XXXX or xxxxxx@xxxxxxx.edu. Thank you in advance for your time and for your assistance with this research project. Sincerely, Elizabeth Silva, ATC Graduate Assistant Athletic Trainer California State University, Sacramento Participants for this survey were selected at random from the NATA membership database according to the selection criteria provided by the student doing the survey. This student survey is not approved or endorsed by NATA. It is being sent to you because of NATA’s commitment to athletic training education and research. 43 REFERENCES (1990). Dorland's illustrated medical dictionary. (26 ed.). Philadelphia: W. B. Saunders Company. Alentron-Geli, E., Myer G. 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