Iliotibial Band Stretching and Figure 4. Turnout Exercise in the Treatment of. Iliotibial Band Friction Syndrome

Transcription

1 Iliotibial Band Stretching and Figure 4 Turnout Exercise in the Treatment of Iliotibial Band Friction Syndrome Sungdae Choung The Graduate School Yonsei University Department of Physical Therapy

2 Iliotibial Band Stretching and Figure 4 Turnout Exercise in the Treatment of Iliotibial Band Friction Syndrome A Dissertation Submitted to the Department of Physical Therapy and the Graduate School of Yonsei University in partial fulfillment of the requirements for the degree of Doctor of Philosophy Sungdae Choung December 2013

3 This certifies that the doctoral dissertation of Sungdae Choung is approved. Thesis Supervisor: Ohyun Kwon Chunghwi Yi: Thesis Committee Member #1 Hyeseon Jeon: Thesis Committee Member #2 Heonseock Cynn: Thesis Committee Member #3 Jonghyuck Weon: Thesis Committee Member #4 The Graduate School Yonsei University December 2013

4 Acknowledgments Many people contributed to my progress in preparing this dissertation, and I am grateful to all those who made it possible. First of all, I would like to thank Professor Ohyun Kwon for his guidance and support. As my primary mentor and director, he encouraged me in this dissertation and always helped me to progress a creative research topic, experiments, and writing of my studies. Despite my lack of knowledge and skills in certain areas, he gave me opportunities to growth academically and clinically. I could not express my deep gratitude to him. Additionally, I would also like to thanks Professor Chunghwi Yi. He taught and gave me his academic experience and vast knowledge. I would like to express my gratitude to Professor Hyeseon Jeon who has always given me continued attention with her warm smile. My gratitude also goes to Professor Heonseock Cynn who embraced me with encouragement and intelligent advice. I sincerely appreciate Professor Jonghyuck Weon who gave me copious advice and guidance. I also appreciate Professor Sanghyun Cho and Professor Joshua You who taught me in various ways during the course. I owe my deepest gratitude to all the members of KEMA, especially Taeho Kim, Junhyeok Jang, Doyoung Jung, Jaesop Oh, Munwhan Kim, Wonwhee Lee, Sungmin Ha, and Kyeunam Park. Whenever I was in trouble, they were there for me and gave the possibility to complete the course. I also thank my colleagues, Sujung Kim, Sihyun Kim, Incheol Jeon, Uijae Hwang, and Sunhee Ahn, who shared the joys and

5 sorrows, always giving me valuable support and encouragement. I would also like to express my deep gratitude to all members in the graduate school department of Physical Therapy. Most importantly, I would like to take this moment to thank my family, who always supported me, especially my parents, who given constant love and encouragement. Without their endless love and care, I could not finish the course. I sincerely love you all. I will not satisfy with my own achievement at this time, I will make an effort to make further progress. Thank you.

6 Table of Contents List of Figures iii List of Tables iv Abstract v Introduction 1 Method 4 1. Subjects 4 2. Experimental Equipment Three Dimensional Electromagnetic Motion Tracking System Ober s Test Using Inclinometer Visual Analog Scale (VAS) Hand-Held Dynamometer (HHD) 9 3. Exercise Programs ITB Stretching Figure 4 Turnout Exercise Experimental Procedure Statistical Analysis 15 Results Comparison of the Pre Program Parameters Between the Two Groups 16 - i -

7 2. Comparison of the Pre and Post Program Parameters in the Two Groups Comparison of the Post Program Parameters in the Two Groups 21 Discussion 23 Conclusion 29 References 30 Abstract in Korean 36 - ii -

8 List of Figures Figure 1. ITB stretching exercise 11 Figure 2. Figure 4 turnout exercise 13 List of Tables - iii -

9 Table 1. Subjects characteristics 5 Table 2. Comparison of angle of pelvis and lower extremity and intensity of lateral knee pain during SLSKB, ITB tightness, and hip abductor and external rotator strength at pre program between two groups 17 Table 3. Comparison of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in stretching group 19 Table 4. Comparison of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in stretching plus strengthening group 20 Table 5. Comparison of differences of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in two groups 22 - iv -

10 ABSTRACT Iliotibial Band Stretching and Figure 4 Turnout Exercise in the Treatment of Iliotibial Band Friction Syndrome Sungdae Choung Dept. of Physical Therapy The Graduate School Yonsei University Atypical hip and knee kinematics caused by iliotibial band (ITB) tightness and/or weakness of the hip abductor contribute to iliotibial band friction syndrome (ITBFS). Therefore, most rehabilitation plans for treating ITBFS include exercises for increasing ITB flexibility and strengthening hip abductor and external rotator muscles to prevent hip adduction and medial rotation. This study compared the effects of 6 week ITB stretching and ITB stretching plus side lying Figure 4 (Figure 4) turnout - v -

11 exercises (hip abduction and external rotation exercise) on lateral knee pain as well as the angles of pelvic lateral tilting, hip adduction and medial rotation and tibial medial rotation during single leg small knee bend (SLSKB, 20 knee flexion) in subjects with ITBFS. A total of 26 male subjects with ITBFS (18 right legs and 8 left legs) were recruited from a workplace based work conditioning center in an automobile assembly plant in Wonju, Korea. Using random sampling numbers, the subjects were randomly assigned to one of the two groups: the ITB stretching group (stretching group, n=13) and the ITB stretching plus Figure 4 exercise group (stretching plus strengthening group, n=13). The kinematic data of the pelvis, hip, and knee were measured using a three dimensional electromagnetic motion tracking system, the intensity of lateral knee pain was measured using a visual analog scale, ITB tightness was assessed using the Ober s test and the hip abductor and external rotator strengths were determined using a hand held dynamometer before and after the 6 week program. The results of this study showed that hip adduction, tibial medial rotation, ITB tightness and intensity of lateral knee pain were significantly decreased after the 6 week ITB stretching program (p < 0.05). The pelvic lateral tilt, hip adduction, hip medial rotation, tibial medial rotation, ITB tightness and lateral knee pain were significantly decreased, and the strength of the hip abductor and external rotator were significantly increased after the 6 week ITB stretching plus Figure 4 exercise program (p < 0.05). Compared with the stretching group and the stretching plus strengthening group showed significantly decreased angles of pelvic lateral tilt, hip adduction and tibial medial rotation as well as significantly increased strength of the - vi -

12 hip abductor and external rotator (p < 0.05). Therefore, the ITB stretching plus Figure 4 exercise can be recommended for treating patients with ITBFS rather than ITB stretching alone. Key Words: Figure 4 turnout exercise, Iliotibial band friction syndrome, Iliotibial band stretching. - vii -

13 Introduction The iliotibial band (ITB) is a thick continuation of the tensor fasciae latae (TFL) muscle. The band originates at the lateral iliac crest immediately behind the anterior superior iliac spine of the pelvis and inserts distally to the lateral border of the patella, the lateral patellar retinaculum, Gerdy s tubercle of the tibia and biceps femoris tendon (Panni et al. 2002; Terry, Hughston, and Norwood 1986). The ITB passes over the lateral femoral condyle at the knee joint (Birnbaum et al. 2004; Orava 1978), and it moves anterior and posterior to the lateral condyle as the knee extends and flexes (Evans 1979). Iliotibial band friction syndrome (ITBFS) results from repetitive friction of the ITB sliding over the lateral femoral condyle. ITBFS is the second most common overuse injury and the most common cause of lateral knee pain in runners; it accounts for % of injuries related to running (Barber and Sutker 1992; Taunton et al. 2002). In addition, it is common in cyclists, weightlifters, skiers and soccer players (McNicol, Taunton and Clement 1981; Orava 1978; Orchard et al. 1996). Lateral knee pain is commonly caused by inflammation of the distal insertion of the ITB (Hamill et al. 2008; Merican, and Amis 2009), and patients with ITBFS complain of a sharp pain or burning sensation in the lateral knee. The etiologic factors related to ITBFS include greater weekly mileage with knee flexion (Mossberg, and Smith 1983) and hip abductor weakness (Fredericson et al. 2000). Additionally, the ITB in patients with ITBFS is significantly different from that in individuals without ITBFS. In a magnetic resonance imaging study, Ekman et - 1 -

14 al. (1994) found that patients with ITBFS had significantly thicker ITB than the control group without symptoms. The thicker ITB causes increased tension, which causes ITB tightness. Furthermore, immediately after the foot strike in the gait cycle, the ITB under greater tension may impinge against the lateral condyle where there is no bursa to protect from impingement (Muhle et al. 1999). Eventually, friction or maximum impingement causes lateral knee pain at the early stance phase, or ~20 30 of knee flexion (Orchard et al. 1996). Several reports have investigated the kinematics of the lower extremity in relation to the site of knee joint symptoms associated with ITBFS. Sahrmann (2011) suggested that the stresses of repetitive tibial rotation in the transverse plane with ITB tightness might eventually lead to knee pain. Other researchers suggested that increased hip adduction and tibial medial rotation caused by a weakened hip abductor might lead to strain and tension on the ITB and worsen this condition (Noehren, Davis, and Hamill 2007; Orava 1978). Several researchers suggested that atypical hip and knee kinematics caused by ITB tightness and/or weakness of the hip abductor might contribute to ITBFS (Ferber et al. 2010; Fredericson et al. 2000; Noehren, Davis, and Hamill 2007). With the goal of decreasing the impingement on the lateral femoral condyle, most rehabilitation plans for treating ITBFS include ITB flexibility exercises and hip abductor and external rotator muscle strengthening exercises to prevent hip adduction and medial rotation (Fredericson, Guillet, and DeBenedictis 2000; Fredericson et al. 2002; Orchard et al. 1996). Although previous studies have suggested that the ITB - 2 -

15 stretching or gluteus medius muscle strengthening exercises decrease ITBFS related pain, no studies have compared the effects of ITB stretching exercise alone to those with ITB stretching plus hip abductor and external rotator strengthening exercise. Therefore, this study aimed to compare the effects of 6 weeks of the ITB stretching exercise to those with the ITB stretching plus side lying Figure 4 turnout (Figure 4) exercise (hip abduction and external rotation exercise) on lateral knee pain as well as the kinematics of the pelvis and lower extremity during single leg small knee bend (SLSKB, 20 knee flexion) in subjects with ITBFS. It was hypothesized that while both ITB stretching and ITB stretching plus Figure 4 exercise programs would decrease lateral knee pain, the ITB stretching plus Figure 4 exercise program would show greater improvement in the kinematics of the pelvis and lower extremity during SLSKB after 6 week intervention compared to the ITB stretching program. Method - 3 -

16 1. Subjects A total of 26 male subjects with ITBFS (18 right legs and 8 left legs) were recruited from a workplace based work conditioning center in an automobile assembly plant in Wonju, Korea. The subjects were included if they showed a positive response to the Ober s test (> 0 ) (Kendall, McCreary, and Provance 1993), had a weakened hip abductor (< 20 kg ) (Phillips, Lo, and Mastaglia 2000), or lateral knee pain that worsened with two or more of the following: 1) ascending or descending stairs, 2) squatting activities, 3) running and 4) climbing up or down a mountain. The subjects were excluded if they displayed a past or present trauma, previous knee surgery or symptoms that included lateral meniscal injury or degenerative joint disease in the hip or knee joint. The subjects included in this study were randomly assigned to two groups using random sampling numbers: the ITB stretching group (stretching group) and the ITB stretching plus Figure 4 exercise group (stretching plus strengthening group) (Table 1). This study was approved by the Yonsei University Wonju Institutional Review Board. Table 1. Subjects characteristics - 4 -

17 Stretching group (n=13) Stretching plus strengthening group (n=13) Mean ± SD Range Mean ± SD Range t p Age (y) 48.6 ± ~ ± ~ Weight ( kg ) 78.2 ± ~ ± ~ Height ( cm ) ± ~ ± ~ Experimental Equipment - 5 -

18 2.1. Three Dimentional Electromagnetic Motion Tracking System A three dimensional electromagnetic motion tracking system (Polhemus Liberty 240/8 system; Polhemus Incorporated, Colchester, USA) was used to measure the peak angle of pelvic lateral tilt, the adduction and medial rotation of hip and the tibial medial rotation during SLSKB with the symptomatic leg. All kinematic data were collected at 240 Hz using a three channel device in conjunction with the Liberty host software (version 3.0). To record the kinematics of the pelvis and lower extremity, the three sensors ( mm) were placed on the mid point of the sacrum, the anterior mid point of the femur and the mid point of the tibia shaft. The source ( mm), placed in front of the subjects, was mounted on top of a rigid wooden frame to avoid metal interference. The static accuracy of this system was 0.03 inches in root mean square (RMS) for three dimensions and 0.15 RMS for the sensor orientation, and the latency was 3.5 ms (Polhemus Specifications, 2007). The recorded data were exported to an ASCII file and analyzed manually using Microsoft Excel by an independent investigator. 2.2 Ober s Test Using Inclinometer - 6 -

19 The Ober s test was used to measure the tightness of the ITB (Kendall, McCreary and Provance 1993). The subject assumed the side lying position on the non tested side. To prevent compensative lumbar or pelvic motion, the subject was asked to flex his hip and knee to 45 to maintain a neutral lumbar lordosis. Next, the examiner raised the subject s top leg into a slight hip abduction position with the knee extended toward the ceiling. The examiner allowed the leg to drop perpendicularly into the hip adduction position. The examiner stabilized the pelvis with one hand, and a bubble inclinometer (Baseline, Fabrication Enterprises Inc., New York) was placed on the lateral femoral condyle with the other hand. Finally, the examiner read and recorded the hip abduction angle. 2.3 Visual Analog Scale (VAS) - 7 -

20 A VAS was used to measure the intensity of the lateral knee pain. The VAS consisted of a 10 cm line, with no pain represented on the left end (0 cm ) and extreme pain on the right end of the line (10 cm ). All patients were asked to mark the line according to the perceived pain level during active daily living, such as ascending or descending stairs, squatting activities, running, and climbing up or down a mountain. 2.4 Hand Held Dynamometer (HHD) - 8 -

21 A HHD (Lafayette Manual Muscle Test System Model 01163, Lafayette Instrument Company, North Lafayette, Indiana, USA) was used to measure the strength of the hip abductor and the external rotator. The HHD was calibrated before testing. The hip abductor and external rotator strength test was performed as described by Phillips, Lo and Mastaglia (2000) in the side lying position. The subject was asked to abduct and externally rotate slightly the upper leg to 20 with knee extension. The subject grasped the side of the plinth to stabilize his trunk. The HHD was placed on the lateral femoral condyle, and resistance was applied perpendicularly. The examiner viewed the digital readout on the HHD and recorded the muscle strength in kilograms. 3. Exercise Programs - 9 -

22 3.1 ITB Stretching The ITB stretching exercise demonstrated by Fredericson et al. (2002) began with the subject standing upright. The leg being stretched was extended slightly and adducted across the opposite leg with hip medial rotation. The fingers were clasped overhead. The subject slowly flexed the trunk in the lateral direction to the opposite side as far as he could flex. The subject held this final posture for 15 sec (Figure 1). This stretching exercise was performed three times per day, 5 days per week during 6 weeks. If the subjects did not feel or complain about lateral knee pain in the leg, the exercises were gradually increased over a course of several weeks to the goal of 10 times per day

23 Figure 1. ITB stretching exercise

24 3.2 Figure 4 Turnout Exercise Figure 4 exercise was performed in the side lying position, with the bottom hip and knee extended, the top hip flexed 45 and the knee flexed 90. The subject was asked to lie with his back against the wall to prevent the compensative pelvic or lumbar rotation. The subject was instructed to rotate the leg externally toward the wall without compensatory motion in the pelvis, lumbar or trunk. The subjects held the final posture for 15 sec (Figure 2). The Figure 4 exercise was performed three times per day, 5 days per week during 6 weeks. If subjects did not feel or complain about lateral knee pain in the leg, the exercise was increased gradually over a course of several weeks to the goal of 10 times per day. In the fourth week, if subjects could perform the exercise without discomfort or pain, the exercise was progressed to include resistance exercise with a thera band between both knees. The subjects were asked to perform the resistance exercise using a thera band 10 times per day

25 Figure 2. Figure 4 turnout exercise

26 4. Experimental Procedure The angles of the pelvic lateral tilt, hip adduction, hip medial rotation and tibial medial rotation were measured using a three dimensional electromagnetic motion tracking system during SLSKB. Each subject was asked to stand on only the symptomatic leg while crossing the arm. Next, the subject was asked to squat using the symptomatic knee to the target bar while looking straight ahead. The target bar was placed at a position requiring 20 knee flexion from the starting position of the knee. Kinematic data were collected from the starting position to the position in which the patella touched the target bar. The examiner assessed the intensity of lateral knee pain using the VAS, ITB tightness with the Ober s test, and the strength of the hip abductor and external rotator using a HHD. All parameters except the VAS were measured three times before and after the 6 week program, and the average was used for data analysis. Following the initial measurement, the principal investigator explained and demonstrated the ITB stretching and Figure 4 exercise. The subjects also received guidelines for performing the 6 week exercise program. All exercises performed by the subjects were monitored by an experienced physical therapist. The physical therapist played a role in guiding the subjects to perform each exercise using the appropriate method

27 5. Statistical Analysis All data are expressed as means and standard deviation. The paired t test and Wilcoxon signed ranks test were used to determine the significance of differences in each group between pre and post programs, and the independent t test and Mann Whitney U test were used to compare the effects of each exercise program between the stretching group and the stretching plus strengthening group, with the level of statistical significance set at a=0.05. The data were analyzed using the SPSS version 12.0 software (SPSS Inc., Chicago, IL, USA)

28 Results 1. Comparison of the Pre Program Parameters Between the Two Groups No significant differences (p > 0.05) were detected in the pre program tests between the two groups in the following measurements: pelvic lateral tilt, hip adduction, hip medial rotation and tibial medial rotation during SLSKB, ITB tightness, intensity of lateral knee pain and the strength of the hip abductor and external rotator (Table 2)

29 Table 2. Comparison of angle of pelvis and lower extremity and intensity of lateral knee pain during SLSKB, ITB tightness, and hip abductor and external rotator strength at pre program between two groups Stretching group (n=13) Stretching plus strengthening group (n=13) Diff. t p Pelvic lateral tilt ( ) ± ± ± Hip adduction ( ) ± ± ± Hip medial rotation ( ) ± ± ± Tibial medial rotation ( ) 7.08 ± ± ± Ober s test ( ) 9.22 ± ± ± VAS (0-10 cm ) 6.00 ± ± ± Hip abductor and external ± ± ± rotator strength ( kg ) Values are mean ± SD. VAS: Visual Analog Scale

30 2. Comparison of the Pre and Post Program Parameters in the Two Groups Significant differences using the paired t test were detected between the pre and post programs at the end of the 6 week program in both groups. In the stretching group, significant decreases were observed in the hip adduction, tibial medial rotation, ITB tightness and the pain intensity in the lateral knee after the 6 week stretching program (p < 0.05). No significant differences were detected in the pelvic lateral tilt, hip medial rotation and strength of the hip abductor and external rotator (Table 3). In the stretching plus strengthening group, significant decreases were observed in the pelvic lateral tilt, hip adduction, hip medial rotation, tibial medial rotation, ITB tightness, and lateral knee pain intensity after the 6 week ITB stretching and Figure 4 exercise program. Additionally, significant increases in the strength of the hip abductor and external rotator were observed after the 6 week program (p < 0.05) (Table 4)

31 Table 3. Comparison of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in stretching group (n=13) Pre program Post program Diff. t p Pelvic lateral tilt ( ) ± ± ± Hip adduction ( ) ± ± ± * Hip medial rotation ( ) ± ± ± Tibial medial rotation ( ) 7.08 ± ± ± * Ober s test ( ) 9.22 ± ± ± < 001* VAS (0-10 cm ) 6.00 ± ± ± Hip abductor and external rotator strength ( kg ) ± ± ± Values are mean ± SD. *Paired t test p < Wilcoxon signed ranks test p < VAS: Visual Analog Scale

32 Table 4. Comparison of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in stretching plus strengthening group (n=13) Pre program Post program Diff. t p Pelvic lateral tilt ( ) ± ± ± < 0.001* Hip adduction ( ) ± ± ± < 0.001* Hip medial rotation ( ) ± ± ± * Tibial medial rotation ( ) 6.67 ± ± ± < 0.001* Ober s test ( ) 9.35 ± ± ± < 0.001* VAS (0-10 cm ) 5.69 ± ± ± 0.95 < Hip abductor and external rotator strength ( kg ) ± ± ± < 0.001* Values are mean ± SD. *Paired t test p < Wilcoxon signed ranks test p < VAS: Visual Analog Scale. 3. Comparison of the Post Program Parameters in the Two Groups

33 Significant decreases were observed in the pelvic lateral tilt, hip adduction and tibial medial rotation in the stretching plus strengthening group post program measurements compared to those in the stretching group. In addition, significant increases were observed in the strength of the hip abductor and external rotator in the stretching plus strengthening group compared to that in the stretching group (p < 0.05). No significant differences were detected in the hip medial rotation, ITB tightness and lateral knee pain intensity between the two groups (p > 0.05) (Table 5). Table 5. Comparison of differences of angle of pelvis and lower extremity and lateral knee pain intensity during SLSKB, ITB tightness, and hip abductor and external rotator strength between pre and post program in two groups

34 stretching group (n=13) Stretching plus strengthening group (n=13) Diff. t p Pelvic lateral tilt ( ) 1.47 ± ± ± * Hip adduction ( ) 2.38 ± ± ± * Hip medial rotation ( ) 1.62 ± ± ± Tibial medial rotation ( ) 3.21 ± ± ± * Ober s test ( ) 9.83 ± ± ± VAS (0-10 cm ) 2.84 ± ± ± Hip abductor and external 0.32 ± ± ± < 0.001* rotator strength ( kg ) Values are mean ± SD. *Independent t test p < VAS: Visual Analog Scale. Discussion

35 This study determined the effects of ITB stretching and Figure 4 exercise on the kinematics of the pelvis and lower extremity and lateral knee pain. The results showed significant decreases in the lateral knee pain in patients enrolled in both 6 week exercise programs. Hip adduction and tibial medial rotation, the main factors in ITBFS, were decreased significantly in patients enrolled in the 6 week ITB stretching program. In addition, the pelvic lateral tilt and hip medial rotation were significantly decreased in patients after the 6 week ITB stretching plus Figure 4 exercise program. The decreased kinematic values in all parameters, except for hip medial rotation, were greater in the ITB stretching plus Figure 4 exercise group compared to those in the ITB stretching group. The combination of tensile force from the hip adduction and tibial medial rotation is likely to result in greater tissue strain in the knee joint (Fairclough et al. 2006; Ferber et al. 2010; Noehren, Davis, and Hamill 2007). Ferber et al. (2010) reported that female runners with ITBFS showed a greater peak hip adduction and tibial medial rotation compared to those without ITBFS. The first measurements in this study were consistent with two studies that reported atypical motion in runners with ITBFS (Ferber et al. 2010; Noehren, Davis, and Hamill 2007). After the two 6 week exercise programs, this study found that the two exercise programs resulted in similar significant decreases in the hip adduction and tibial medial rotation. Although the measured changes in hip adduction (2.38 ± 3.72, 7.02 ± 3.07, respectively) and tibial medial rotation (3.21 ± ± 2.72, respectively) in the two groups were relatively small, the small decrease in hip adduction and tibial medial rotation could

36 prevent impingement upon the lateral femoral; it is thought that even small differences might be meaningful clinically. The pelvic motion demonstrated in patients with ITBFS has not been commonly considered in previous studies (Fredericson et al. 2000; Hamill et al. 2008; Noehren, Davis and Hamill 2007). However, the atypical movement of the pelvis is important because the ITB originates from the anterior superior iliac spine via the TFL (Birnbaum et al. 2004). A laterally tilted pelvis (hip abduction) would allow decreased tension in the ITB on the lateral femoral condyle, and patients with ITBFS might be pain free while performing daily living activities that require 20 knee flexion such as walking up or down stairs. Although the pelvic lateral tilt would result in reduced lateral knee pain, such a solution would be temporary. Because the posture of the pelvic lateral tilt shortens the ITB, performing this posture continuously might eventually result in shortening the ITB further. We found that the pelvic lateral tilt was demonstrated in subjects with ITFS during SLSKB, and that the pelvic motion was decreased after 6 week ITB stretching plus Figure 4 exercise, but not with ITB stretching alone. We suggest that improved kinematics from the pelvis to the tibia is important for treating ITBFS symptoms, which can be achieved by ITB stretching plus Figure 4 exercise. An electromyographic study suggested that the continuous hip abductor movement is needed by the gluteus medius, but not by the TFL in the coronal plane during the stance phase (Mann, Moran, and Dougherty 1986). In patients with weakness in the gluteus medius, the hip and pelvic stability could not be maintained in the neutral

37 position (McFadyen, and Winter 1988), and the hip abduction could be induced by the relatively stronger TFL. A weakened gluteus muscle may contribute to inducing the hip medial rotation and adduction with joint loading; therefore, it has been associated not only with ITBFS (Fredericson et al. 2000) but also patellofemoral pain syndrome (Ireland et al. 2003; Robinson and Nee 2007) and anterior cruciate ligament sprains (Hewett et al. 2005). The Figure 4 exercise performed in this study is a dissociation exercise that elicits unilateral hip external rotation and abduction with the hip and knee flexed to strengthen the gluteus medius muscle (Distefano et al. 2009). A previous electromyographic study of the gluteus medius muscle activity showed a relatively lower mean amplitude (40% maximum voluntary isometric contraction, MVIC) during Figure 4 exercise compared to the side lying hip abduction (81% MVIC), single limb squat (64% MVIC), single limb dead lift (58% MVIC) and lateral band walk exercises (61% MVIC) in 21 healthy subjects. Nevertheless, in this study, it was selected the Figure 4 exercise because the recruited subjects complained of current lateral knee pain. Therefore, this study chose the Figure 4 exercise rather than introducing an intense exercise with a large external moment arm or close kinetic chain with 20 knee flexion that could influence the lateral knee pain. Because the gluteus medius muscle during Figure 4 exercise has a lower amplitude, this study added additional resistance using the thera band. Thus, we believed that the Figure 4 exercise would be a safe self exercise and would strengthen the other external rotators such as the piriformis as well as the gluteus medius muscle. The results of

38 this study showed that the Figure 4 exercise is sufficient to reduce lateral knee pain and improve the atypical kinematics of the pelvis and lower extremity. Similar to this study, Fredericson et al. (2000) reported the effect of a 6 week standardized rehabilitation program that consisted of nonsteroidal anti inflammatory drugs, ultrasound with corticosterioid gel, two standard ITB stretching exercises and two hip abduction exercises. In their study, athletes with ITBFS who performed the 6 week rehabilitation increased their hip abductor strength from 34.9% to 51.4% BWh (percent body weight height). Additionally, they reported that 22 of the 24 athletes with ITBFS were pain free with the 6 week standardized rehabilitation program. The authors suggested that increased hip abductor strength improved the symptoms. However, because the study was a case series, it is difficult to determine which intervention affected the pain reduction in patients with ITBFS. In this study, it is possible to compare the effects caused by the ITB stretching program or the Figure 4 exercise program in subjects with ITBFS. The subjects with ITBFS in this study who performed the 6 week exercise program showed a decrease in the atypical motion in pelvis and lower extremity. In addition, these subjects showed a decrease in the VAS, from 6.00 and 5.69 to 3.06 and 2.00 cm, respectively. These decreases in the VAS suggest that the clinical pain was reduced; a previous study demonstrated that a minimum reduction of 2 cm on a VAS during daily living activities indicated clinically significant pain reduction (DeLoach et al. 1998). Therefore, we postulated that ITB stretching could reduce the lateral knee pain by decreasing the hip adduction and tibial medial rotation; however, in addition to decreased hip adduction and tibial

39 medial rotation, ITB stretching plus Figure 4 exercise would have the added benefit of increasing the pelvic stability and decreasing the internal rotation with a decreased valgus vector at the knee. No significant difference in pain reduction was observed between the two groups in this study. If the reduction of lateral knee pain resulted only from the decreased hip adduction and tibial medial rotation, then ITB stretching would be recommend; however, abnormal motion in one joint might affect adjacent joints. Therefore, we recommend ITB stretching plus Figure 4 exercise to patients with ITBFS as a better rehabilitation program because it improved the pelvic lateral tilt, hip medial rotation, hip adduction and tibial medial rotation. A prospective study of more than 6 weeks will be required to determine whether the exercises have a long lasting effect on lateral knee pain. We measured the kinematic improvement of the pelvis and lower extremity to identify the effects of two exercise programs; however, this study had several limitations. First, while the onset of muscles used to control the pelvis and lower extremity is an important factor, this study did not measure the muscle onset using electromyography. Further studies are required to determine the onset differences between the gluteus medius and TFL in subjects with ITBFS compared to subjects without ITBFS. Second, additional studies are needed to determine whether ITB stretching Figure 4 exercise is more effective than other conservative interventions, such as ultrasound and nonsteroidal anti inflammatory drugs. Finally, this study included only males, and future studies including both sexes are warranted

40 Conclusion

41 In this 6 week prospective study, the ITB stretching and ITB stretching plus Figure 4 exercise had significant effects in terms of decreasing the atypical kinematics of the pelvis and lower extremity and reducing the lateral knee pain in subjects with ITBFS. Furthermore, the ITB stretching plus Figure 4 exercise program had greater effects on the kinematics of the pelvis and lower extremity compared to the ITB stretching program. This study suggests that ITB stretching plus Figure 4 exercise should be recommended to patients with ITBFS to achieve additional improvement of the pelvic lateral tilt, hip adduction, and tibial medial rotation. This program provided better rehabilitation to patients with ITBFS compared to ITB stretching alone. References

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48 엉덩정강근막띠마찰증후군치료에서의 엉덩정강근막띠신장운동과 4 자형 바깥돌림근력강화운동 연세대학교대학원 물리치료학과 정성대 이전연구들은엉덩정강근막띠의뻣뻣함으로야기되는엉덩관절과무릎관절의비정형적인운동학또는엉덩관절벌림근의약화를엉덩정강근막띠마찰증후군 (iliotibial band friction syndrome) 의주된원인으로제시하였다. 따라서, 엉덩정강근막띠를치료하기위한대부분의재활계획들은엉덩정강근막띠의유연성을증가시키기위한운동과엉덩관절모음과안쪽돌림을방지하기위해엉덩관절벌림근과바깥회전근들을강화시키기위한운동들을포함한다. 본연구의목적은엉덩관절근막띠마찰증후군이있는대상자들이한쪽무릎관절작은굽힘 (single leg small knee bend, 무릎관절굽힘 20 ) 을하는동안무릎

49 바깥쪽통증과골반및다리의운동형상학데이터에서 6주동안의엉덩정강근막띠신장운동프로그램과엉덩정강근막띠신장운동프로그램에 4자형바깥돌림근력강화운동을병행한프로그램간의효과를비교하는데있다. 엉덩정강근막띠마찰증후군이있는 26명의남성대상자 ( 오른쪽다리 18명, 왼쪽다리 8명 ) 들이본연구에참여하였다. 그대상자들은난수표를이용하여무작위로두군에할당되었다 ; 엉덩정강근막띠신장운동군 (13명), 엉덩정강근막띠신장운동에 4자형바깥돌림근력강화운동을병행하는군 (13명). 모든대상자들은 3차원전자석운동추적장비를이용하여골반바깥쪽기울임, 엉덩관절모음, 엉덩관절안쪽돌림과정강뼈안쪽돌림의운동형상학을, 시각상사척도를이용하여무릎바깥쪽통증을, 오버검사 (Ober s test) 를이용하여엉덩정강근막띠뻣뻣함을, 휴대용역량계 (hand-held dynamometer) 를이용하여엉덩관절벌림근과바깥돌림근의근력을각각 6주프로그램전과후에측정하였다. 6주엉덩정강근막띠신장운동후엉덩관절모음, 정강뼈안쪽돌림, 엉덩정강근막띠뻣뻣함과무릎바깥쪽통증이유의하게감소하였다 (p < 0.05). 6주동안엉덩정강근막띠신장운동과 4자형바깥돌림근력강화운동을병행한프로그램후에도골반바깥기울임, 엉덩관절모음및안쪽돌림, 정강뼈안쪽돌림. 엉덩정강근막띠뻣뻣함과무릎바깥쪽통증이유의하게감소하였고, 엉덩관절벌림근과바깥돌림근의근력이유의하게

50 증가하였다 (p < 0.05). 엉덩정강근막띠신장운동에 4자형바깥돌림근력강화운동을병행한군이엉덩정강근막띠신장운동만수행한군보다골반바깥기울임, 엉덩관절모음과정강뼈안쪽돌림이더유의하게감소하였고, 엉덩관절벌림근과바깥돌림근의근력이더유의하게증가하였다 (p < 0.05). 본 6주동안의전향적연구에서는엉덩정강근막띠신장운동과 4자형바깥돌림근력강화운동을병행한프로그램이엉덩정강근막띠마찰증후군이있는대상자들에게골반과다리의비정형적운동형상학데이터를감소시키고무릎바깥쪽통증을감소시키는데유의한효과가있었다. 그러므로, 본연구는엉덩정강근막띠마찰증후군이있는환자들에게엉덩정강근막띠신장운동과 4자형바깥돌림근력강화운동을병행할것을추천한다. 핵심되는말 : 엉덩정강근막띠마찰증후군, 엉덩정강근막띠신장운동, 4 자형바깥돌림근력강화운동