Mulligan Knee Taping Using Both Elastic and Rigid Tape Reduces Pain and Alters Lower Limb Biomechanics in Female Patients With Patellofemoral Pain.

BACKGROUND: Evidence supports the use of Mulligan knee taping in managing patellofemoral pain (PFP). However, no studies have compared the efficacy of rigid and elastic tape using this technique. HYPOTHESIS: Mulligan knee taping applied with both rigid and elastic tape will produce similar reductions in knee pain, hip internal rotation, and knee flexion moments compared with no tape. Elastic tape will also be more comfortable than rigid tape. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 19 female patients (mean age, 26.5 ± 4.5 years) with PFP performed a self-selected pain provocative task, single-leg squat (SLSq) task, and running task while wearing Mulligan knee taping applied with rigid tape, elastic tape at 100% tension, and no tape. Pain and taping comfort were recorded using 11-point numeric rating scales. An 18-camera motion capture system and in-ground force plates recorded 3-dimensional lower limb kinematics and kinetics for the SLSq and running tasks. Statistical analysis involved a series of repeated-measures analyses of variance. The Wilcoxon signed rank test was used for analyzing taping comfort. RESULTS: Compared with no tape, both rigid and elastic tape significantly reduced pain during the pain provocative task (mean difference [MD], -0.97 [95% CI, -1.57 to -0.38] and -1.42 [95% CI, -2.20 to -0.64], respectively), SLSq (MD, -1.26 [95% CI, -2.23 to -0.30] and -1.13 [95% CI, -2.09 to -0.17], respectively), and running tasks (MD, -1.24 [95% CI, -2.11 to -0.37] and -1.16 [95% CI, -1.86 to -0.46], respectively). Elastic tape was significantly more comfortable than rigid tape generally (P = .005) and during activity (P = .022). Compared with no tape, both rigid and elastic tape produced increased knee internal rotation at initial contact during the running task (MD, 5.5° [95% CI, 3.6° to 7.4°] and 5.9° [95% CI, 3.9° to 7.9°], respectively) and at the commencement of knee flexion during the SLSq task (MD, 5.8° [95% CI, 4.5° to 7.0°] and 5.8° [95% CI, 4.1° to 7.4°], respectively), greater peak knee internal rotation during the running (MD, 1.8° [95% CI, 0.4° to 3.3°] and 2.2° [95% CI, 0.9° to 3.6°], respectively) and SLSq tasks (MD, 3.2° [95% CI, 2.1° to 4.3°] and 3.8° [95% CI, 2.3° to 5.2°], respectively), and decreased knee internal rotation range of motion during the running (MD, -3.6° [95% CI, -6.1° to -1.1°] and -3.7° [95% CI, -6.2° to -1.2°], respectively) and SLSq tasks (MD, -2.5° [95% CI, -3.9° to -1.2°] and -2.0° [95% CI, -3.2° to -0.9°], respectively). CONCLUSION: Mulligan knee taping with both rigid and elastic tape reduced pain across all 3 tasks and altered tibiofemoral rotation during the SLSq and running tasks. CLINICAL RELEVANCE: Both taping methods reduced pain and altered lower limb biomechanics. Elastic tape may be chosen clinically for comfort reasons.

Deceleration characteristics of elite Australian male field hockey players during an Olympic tournament.

OBJECTIVES: This study described the deceleration efforts of the Australian men's field hockey team during the 2016 Olympics by categorising efforts into 'bands' of intensity; and comparing the deceleration intensity and frequency by player position, game period and opponent. DESIGN: Descriptive retrospective analysis. METHODS: Global positioning system sensors (MinimaxX S4, Catapult Sports Pty. Ltd., Melbourne, Australia; 10Hz) were worn by 15 male field hockey players during six games of the 2016 Olympic tournament. RESULTS: There were 8998 individual deceleration efforts (≤-3ms-2) performed over the tournament with the most intense effort measured at -13.6ms-2. Deceleration intensity 'bands' were calculated using Receiver Operator Characteristic (ROC) curves as low intensity=-3 to -5.99ms-2; medium intensity=-6 to -8.99ms-2; high intensity=-9 to -11.99ms-2; and, very high intensity=<-12ms-2. There were no significantly different decelerations between field positions but decelerations performed within game period one were more intense than game period two (-0.11±0.01ms-2, p<0.001). Deceleration efforts were more frequent in game period one than two [X2(3, N=8997)=12.00, p=0.007]. CONCLUSIONS: Decelerations are common in elite field hockey and very high intensities are present. These findings, in conjunction with other metrics can be used as a tool to monitor the load associated with training and match play in field hockey.

Differences in lower limb biomechanics between ballet dancers and non-dancers during functional landing tasks.

OBJECTIVES: To determine the differences in the lower limb landing biomechanics of adolescent ballet dancers compared to non-dancers when performing a hop and a stop jump task. DESIGN: Cross-sectional. SETTING: Laboratory. PARTICIPANTS: Thirteen adolescent female ballet dancers (11.8 ±â€¯1.1 years) and 17 non-dancers (10.9 ±â€¯0.8 years) performed hop and stop jump tasks. MAIN OUTCOME MEASURES: Vertical ground reaction force, and three-dimensional ankle, knee and hip joint angles and moments during the landing phase. RESULTS: Dancers displayed greater sagittal plane joint excursions during the hop and stop jump at the ankle (mean difference = 22.0°, P < 0.001, 14.8°, P < 0.001 respectively), knee (mean difference = 18.1°, P = 0.001, 9.8°, P = 0.002 respectively) and hip (stop jump task; mean difference = 8.3°, P = 0.008). Dancers displayed a larger hip extensor moment compared to non-dancers (P < 0.001) during the stop jump task only. Dancers also took longer to reach peak vGRF and jumped three times higher than non-dancers (P < 0.001) during the stop jump task. No difference in peak vGRF between groups was displayed for either task. CONCLUSIONS: Adolescent dancers demonstrate a transfer of landing technique to non-ballet specific tasks, reflective of the greater jump height and sagittal plane joint excursions. This landing strategy may be associated with the low rate of non-contact ACL injuries in female dancers.

A biomechanical comparison in the lower limb and lumbar spine between a hit and drag flick in field hockey.

Research has revealed that field hockey drag flickers have greater odds of hip and lumbar injuries compared to non-drag flickers (DF). This study aimed to compare the biomechanics of a field hockey hit and a specialised field hockey drag flick. Eighteen male and seven female specialised hockey DF performed a hit and a drag flick in a motion analysis laboratory with an 18-camera three-dimensional motion analysis system and a calibrated multichannel force platform to examine differences in lower limb and lumbar kinematics and kinetics. Results revealed that drag flicks were performed with more of a forward lunge on the left lower limb resulting in significantly greater left ankle dorsiflexion, knee, hip and lumbar flexion (Ps<0.001) compared to a hit. Drag flicks were also performed with significantly greater lateral flexion (P < 0.002) and rotation of the lumbar spine (P < 0.006) compared to a hit. Differences in kinematics lead to greater shear, compression and tensile forces in multiple left lower limb and lumbar joints in the drag flick compared to the hit (P < 0.05). The biomechanical differences in drag flicks compared to a hit may have ramifications with respect to injury in field hockey drag flickers.

Lower Limb and Trunk Biomechanics After Fatigue in Competitive Female Irish Dancers.

CONTEXT: Because of the increasing popularity of participation in Irish dance, the incidence of lower limb injuries is high among this competitive population. OBJECTIVE: To investigate the effects of fatigue on the peak lower limb and trunk angles as well as the peak lower limb joint forces and moments of competitive female Irish dancers during the performance of a dance-specific single-limb landing. DESIGN: Cross-sectional study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Fourteen healthy, female, competitive Irish dancers (age = 19.4 ± 3.7 years, height = 165.3 ± 5.9 cm, mass = 57.9 ± 8.2 kg). INTERVENTION(S): Participants performed an Irish dance-specific leap before and after a dance-specific fatigue protocol. During each landing movement, 3-dimensional lower limb kinematics (250 Hz) and ground reaction forces (1000 Hz) were collected. Paired t tests were performed to determine the differences (P ≤ .05) in lower limb and trunk biomechanics prefatigue and postfatigue. MAIN OUTCOME MEASURE(S): Peak lower limb and trunk angles as well as peak lower limb joint reaction forces and external moments. RESULTS: Compared with the prefatigue trials, dancers landed with reduced ankle plantar flexion (P = .003) and hip external rotation (P = .007) and increased hip-adduction alignment (P = .034) postfatigue. Dancers displayed greater anterior shear (P = .003) and compressive (P = .024) forces at the ankle and greater external knee-flexion moments (P = .024) during the postfatigue compared with the prefatigue landing trials. CONCLUSIONS: When fatigued, dancers displayed a decline in landing performance in terms of aesthetics as well as increased ankle- and knee-joint loading, potentially exposing them to a greater risk of injuries.

Higher anterior knee laxity influences the landing biomechanics displayed by pubescent girls.

Despite an increase in anterior knee laxity (AKL) during the adolescent growth spurt in girls, it is unknown whether landing biomechanics are affected by this change. This study investigated whether pubescent girls with higher AKL displayed differences in their lower limb strength or landing biomechanics when performing a horizontal leap movement compared to girls with lower AKL. Forty-six pubescent girls (10-13 years) were tested at the time of their peak height velocity (PHV). Passive AKL was quantified and used to classify participants into higher (HAKL; peak displacement > 4 mm) and lower (LAKL; peak displacement < 3 mm) AKL groups (n = 15/group). Three-dimensional kinematics, ground reaction forces (GRF) and muscle activation patterns were assessed during a horizontal leap landing. HAKL participants displayed significantly (P < 0.05) reduced hip abduction, increased hip abduction moments, as well as earlier hamstring muscle and later tibialis anterior activation compared to LAKL participants. Girls with HAKL displayed compensatory landing biomechanics, which are suggested to assist the functional stability of their knees during this dynamic task. Further research is warranted, however, to confirm or refute this notion.

Effect of External Ankle Support on Ankle and Knee Biomechanics During the Cutting Maneuver in Basketball Players.

BACKGROUND: Despite the high prevalence of lower extremity injuries in female basketball players as well as a high proportion of athletes who wear ankle braces, there is a paucity of research pertaining to the effects of ankle bracing on ankle and knee biomechanics during basketball-specific tasks. PURPOSE: To compare the effects of a lace-up brace (ASO), a hinged brace (Active T2), and no ankle bracing (control) on ankle and knee joint kinematics and joint reaction forces in female basketball athletes during a cutting maneuver. STUDY DESIGN: Controlled laboratory study. METHODS: Twenty healthy, semi-elite female basketball players performed a cutting task under both ankle brace conditions (lace-up ankle brace and hinged ankle brace) and a no-brace condition. The 3-dimensional kinematics of the ankle and knee during the cutting maneuver were measured with an 18-camera motion analysis system (250 Hz), and ground-reaction force data were collected by use of a multichannel force plate (2000 Hz) to quantify ankle and knee joint reaction forces. Conditions were randomized using a block randomization method. RESULTS: Compared with the control condition, the hinged ankle brace significantly restricted peak ankle inversion (mean difference, 1.7°; P = .023). No significant difference was found between the lace-up brace and the control condition ( P = .865). Compared with the lace-up brace, the hinged brace significantly reduced ankle and knee joint compressive forces at the time of peak ankle dorsiflexion (mean difference, 1.5 N/kg [ P = .018] and 1.4 N/kg [ P = .013], respectively). Additionally, the hinged ankle brace significantly reduced knee anterior shear forces compared with the lace-up brace both during the deceleration phase and at peak ankle dorsiflexion (mean difference, 0.8 N/kg [ P = .018] and 0.9 N/kg [ P = .011], respectively). CONCLUSION: The hinged ankle brace significantly reduced ankle inversion compared with the no-brace condition and reduced ankle and knee joint forces compared with the lace-up brace in a female basketball population during a cutting task. Compared with the lace-up brace, the hinged brace may be a better choice of prophylactic ankle support for female basketball players from a biomechanical perspective. However, both braces increased knee internal rotation and knee abduction angles, which may be problematic for a population that already has a high prevalence of knee injuries.

The Effect of the Mulligan Knee Taping Technique on Patellofemoral Pain and Lower Limb Biomechanics.

BACKGROUND: Patellofemoral pain (PFP) affects 25% of the general population, occurring 2 times more often in females compared with males. Taping is a valuable component of the management plan for altering lower limb biomechanics and providing pain relief; however, the effects of alternative taping techniques, such as Mulligan knee taping, appear yet to be researched. PURPOSE: To determine whether the Mulligan knee taping technique altered levels of perceived knee pain and lower limb biomechanics during a single-legged squat (SLSq) in adult females with PFP. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 20 female patients with PFP, aged 18 to 35 years, participated in this study. Participants performed 3 to 5 SLSq on their most symptomatic limb during a taped (Mulligan knee taping technique) and nontaped (control) condition. During the eccentric phase of the SLSq, the 3-dimensional kinematics (250 Hz) of the knee and hip and the ground-reaction forces (1000 Hz) and muscle activation patterns (1000 Hz) of the gluteus medius, vastus lateralis, and vastus medialis oblique were measured. Participants' perceived maximum knee pain was also recorded after the completion of each squat. RESULTS: Between-condition differences were found for hip kinematics and gluteus medius activation but not for kinetics or vastus medialis oblique and vastus lateralis muscle activity (timing and activation). Compared with the nontaped condition, the Mulligan knee taping technique significantly (P = .001) reduced perceived pain during the SLSq (mean ± SD: 2.29 ± 1.79 and 1.29 ± 1.28, respectively). In the taped condition compared with the control, the onset timing of the gluteus medius occurred significantly earlier (120.6 ± 113.0 and 156.6 ± 91.6 ms, respectively; P = .023) and peak hip internal rotation was significantly reduced (6.38° ± 7.31° and 8.34° ± 7.92°, respectively; P = .002). CONCLUSION: The Mulligan knee taping technique successfully reduced knee pain in participants with PFP. This is the first study to establish a link between Mulligan knee taping and the reduction of PFP in conjunction with decreased hip internal rotation and earlier activation of gluteus medius. CLINICAL RELEVANCE: The Mulligan knee taping technique may benefit the clinical environment by providing an alternative evidence-based treatment plan for PFP.

How Young Girls Change Their Landing Technique Throughout the Adolescent Growth Spurt.

BACKGROUND: Despite the rapid musculoskeletal changes experienced by girls throughout the adolescent growth spurt, little is known about how their lower limb landing technique changes during this time. PURPOSE: To investigate the longitudinal changes in the 3-dimensional lower limb kinematics, joint moments, and muscle activation patterns displayed by girls when performing a horizontal landing task throughout their adolescent growth spurt. STUDY DESIGN: Descriptive laboratory study. METHODS: A total of 33 healthy 10- to 13-year-old girls, in Tanner stage II, with a maturity offset of -6 to -4 months (time from peak height velocity) were recruited. According to her maturity offset, each participant was tested up to 4 times during the 12 months of her growth spurt (maturity offset: test 1 = -6 to -4 months; test 2 = 0 months; test 3 = 4 months; test 4 = 8 months). During each test session, participants performed a horizontal leap movement, during which ground-reaction forces (1000 Hz), lower limb muscle activity (1000 Hz), and kinematic data (100 Hz) were collected. RESULTS: Throughout the growth spurt, girls displayed a decrease in knee flexion (P = .028), increase in hip flexion (P = .047), increase in external knee abduction moments (P = .008), and decrease in external hip adduction moments (P = .003) during the landing movement. CONCLUSION: During their adolescent growth spurt, pubescent girls displayed a change in the strategy with which they controlled their lower limb to land after performing a horizontal leap movement. This change in the landing strategy has the potential to increase the risk of anterior cruciate ligament injuries toward the latter stages of the adolescent growth spurt. CLINICAL RELEVANCE: The outcomes of this research provide a greater understanding of the changes in the landing strategy used by pubescent girls throughout the adolescent growth spurt. This can assist in the development of screening tools designed to determine "at-risk" landing biomechanics during puberty.

Insufficient hamstring strength compromises landing technique in adolescent girls.

PURPOSE: Women sustain more anterior cruciate ligament (ACL) ruptures than men, and this gender disparity is apparent from pubertal onset. Although the hamstring muscles play a vital role in ACL protection during landing by restraining anterior tibial motion relative to the femur, it is unknown whether hamstring strength affects landing biomechanics during a functional movement. This study aimed to determine whether pubescent girls with lower hamstring strength displayed different lower limb biomechanics when landing from a leap compared with girls with higher hamstring strength. METHODS: Thirty-three healthy girls, age 10-13 yr, in Tanner stage II (pubertal onset) and 4-6 months from their peak height velocity were recruited. The concentric and the eccentric isokinetic strength of the hamstring and quadriceps muscles were assessed. On the basis of peak concentric hamstrings torque, participants were divided into a lower (peak torque < 45 N·m) and higher (peak torque > 60 N·m) strength group. Participants performed a functional landing movement, during which ground reaction forces (1000 Hz), lower limb electromyography (1000 Hz), and kinematic data (100 Hz) were collected. RESULTS: Girls with lower hamstring strength displayed significantly (P < 0.05) greater knee abduction alignment, reduced hip abduction moments, and greater ACL loading at the time of the peak anteroposterior ground reaction forces compared with their stronger counterparts. CONCLUSIONS: Girls with reduced hamstring strength appear to have a decreased capacity to control lower limb frontal plane alignment. This reduced capacity appears to contribute to increased ACL loading and, in turn, increased potential for injury.

Musculoskeletal and estrogen changes during the adolescent growth spurt in girls.

INTRODUCTION: The adolescent growth spurt is associated with rapid growth and hormonal changes, thought to contribute to the increased anterior cruciate ligament injury risk in girls. However, relatively little is known about these musculoskeletal and estrogen changes during the growth spurt in girls. PURPOSE: To investigate the longitudinal changes in estrogen as well as anterior knee laxity and lower limb strength and flexibility throughout the adolescent growth spurt in girls. METHODS: Thirty-three healthy girls, age 10-13 yr, in Tanner stage II and 4-6 months from their peak height velocity were recruited. Participants were tested up to four times during the 12 months of their growth spurt, according to the timing of their maturity offset (test 1: maturity offset = -6 to -4 months; test 2: maturity offset = 0 months; test 3: maturity offset = +4 months; test 4: maturity offset = +8 months). During each testing session, anterior knee laxity, lower limb flexibility, and isokinetic strength as well as saliva measures of estradiol concentration were measured. RESULTS: A significant (P = 0.002) effect of time on anterior knee laxity was found from the time of peak height velocity, although no changes in estradiol concentration were displayed over time (P = 0.811). Participants displayed a significant increase (P < 0.05) in isokinetic quadriceps strength over time, with no apparent increase in isokinetic hamstring strength. CONCLUSIONS: We speculate that increased quadriceps strength, combined with increased knee laxity and no accompanying hamstring strength development during the adolescent growth spurt in girls, might contribute to a decrease in their knee joint stability during landing tasks. These musculoskeletal changes could potentially increase anterior cruciate ligament injury risk at a time of rapid height and lower limb growth.

Why do girls sustain more anterior cruciate ligament injuries than boys?: a review of the changes in estrogen and musculoskeletal structure and function during puberty.

Sport is the leading cause of injury among adolescents and girls incur more non-contact anterior cruciate ligament (ACL) ruptures than boys, with this gender disparity in injury incidence apparent from the onset of puberty. Although the mechanisms for this gender disparity in ACL injuries are relatively unknown, hormonal, anatomical and biomechanical factors have been implicated. Puberty is associated with rapid skeletal growth and hormonal influx, both of which are thought to contribute to alterations in ACL metabolic and mechanical properties, as well as changes in lower limb strength and flexibility, ultimately influencing landing technique. Therefore, the aim of this review is to explain (i) the effects of changes in estrogen levels on the metabolic and mechanical properties of the ACL; (ii) changes in musculoskeletal structure and function that occur during puberty, including changes in knee laxity, and lower limb flexibility and strength; and (iii) how these hormonal and musculoskeletal changes impact upon the landing technique displayed by pubescent girls. Despite evidence confirming estrogen receptors on the ACL, there are still conflicting results as to how estrogen affects the mechanical properties of the ACL, particularly during puberty. However, during this time of rapid growth and hormonal influx, unlike their male counterparts, girls do not display an accelerated muscle strength spurt and the development of their hamstring muscle strength appears to lag behind that of their quadriceps. Throughout puberty, girls also display an increase in knee valgus when landing, which is not evident in boys. Therefore, it is plausible that this lack of a defined strength spurt, particularly of the hamstring muscles, combined with the hormonal effects of estrogen in girls, may contribute to a more 'risky' lower limb alignment during landing, in turn, contributing to a greater risk of ACL injury. There is, however, a paucity of longitudinal studies specifically examining the lower limb musculoskeletal structural and functional changes experienced by girls throughout puberty, as well as how these changes are related to estrogen fluctuations characteristic of puberty and their effects on landing biomechanics. Therefore, further research is recommended to provide greater insight as to why pubescent girls are at an increased risk of non-contact ACL injuries during sport compared with boys. Such information will allow the development of evidence-based training programmes aimed at teaching girls to land more safely and with greater control of their lower limbs in an attempt to reduce the incidence of ACL ruptures during puberty.