RESTRICTED HIP MOBILITY: CLINICAL SUGGESTIONS FOR SELF‐MOBILIZATION AND MUSCLE RE‐EDUCATION

Restricted hip mobility has shown strong correlation with various pathologies of the hip, lumbar spine and lower extremity. Restricted mobility can consequently have deleterious effects not only at the involved joint but throughout the entire kinetic chain. Promising findings are suggesting benefit with skilled joint mobilization intervention for clients with various hip pathologies. Supervised home program intervention, while lacking specifically for the hip joint, are demonstrating promising results in other regions of the body. Application of an accompanying home program for the purpose of complementing skilled, in clinic intervention is advisable for those clients that respond favorably to such methodology.

Level of Evidence:

5     

HIP MUSCLE STRENGTH AND ENDURANCE IN FEMALES WITH PATELLOFEMORAL PAIN: A SYSTEMATIC REVIEW WITH META‐ANALYSIS

Purpose/Background:

Patellofemoral pain (PFP) is a common knee conditions experienced by adolescents and young adults, seen particularly in women. Clinicians and researchers need to understand how proximal, local, or distal factors may influence the development of PFP and affect individuals once they have developed PFP. Proximal factors are the focus of recent studies and the purpose of this systematic review was to determine if females with PFP have hip muscle strength or endurance deficits when compared to their unaffected leg and to comparison groups.

Methods:

A systematic review was conducted to identify relevant studies in the databases PubMed, PEDro, ScienceDirect and EBSCOhost up to June 2013. Data including study design, participants demographic data, and assessments of hip muscle strength or endurance were extracted from individual trials. The mean differences of hip muscles strength or endurance between females with PFP and healthy controls or unaffected side were extracted or calculated from individual trials and, when possible, a meta‐analysis was performed.

Results:

Ten cross‐sectional studies were included in this review. Concerning isometric strength, pooled data reported deficit in hip abduction, extension, external rotation and flexion but no deficit in adduction and internal rotation when compared with healthy controls. When compared with the unaffected side, deficit in hip abduction was reported in two studies and deficit in extension and external rotation in one study. Studies with isokinetic strength evaluation reported deficit in abduction but contradictory results for extensors and rotators in females with PFPS. Finally, one study reported hip endurance deficit in extension and one found no significant differences in hip endurance compared to control subjects.

Conclusion:

The results of this systematic review confirm that females with PFPS have deficit in hip muscle strength compared with healthy controls and the unaffected side but are contradictory concerning endurance.

Level Of Evidence:

2a     

GLUTEAL MUSCLE ACTIVITY DURING WEIGHTBEARING AND NON‐WEIGHTBEARING EXERCISE

Background:

Researchers suggest that decreased strength of the gluteus medius (GMed) and the gluteus maximus (GMax) muscles contributes to the etiology of various orthopedic pathologies of the knee. Currently, equivocal evidence exists regarding Electromyography (EMG) activity of gluteal musculature during weightbearing (WB) and non‐weightbearing (NWB) exercise. The purpose of this study was to compare GMed and GMax muscle activation during WB functional exercise and NWB 10 repetition maximum (RM) exercises.

Methods:

Surface EMG electrodes recorded the muscle activity of the GMax and GMed as subjects performed three sets of 10 repetitions of the following exercises: (1) forward step‐up, (2) lateral step‐up, (3) 10 repetition maximum (10 RM) side‐lying hip abduction and (4) 10 RM prone hip extension. The 10 RM resistances were determined one week prior to data collection.

Results:

The GMed was recruited significantly more during side‐lying 10 RM than the remaining exercises (side‐lying, 99.9±17% vs. lateral step‐up, 61±20%; Forward step‐up, 62.7±18.2%; prone, 38±22.2%)(p<0.001). The GMax was recruited to the greatest extent during prone 10 RM hip extension (prone, 100.7±14.5% vs. forward step‐up, 28.7±18.7%; lateral step‐up, 31±19.9%; side‐lying, 38±23.3%)(p<0.001).

Discussion:

These results suggest that performing a 10 RM NWB exercise results in greater muscle activation than two functional WB exercise without load in young, healthy individuals. In addition, forward and lateral step‐ups failed to effectively recruit the GMax at a high enough level to achieve a strengthening stimulus. The GMed was recruited to a higher extent than the GMax during the stepping tasks which might be further augmented if the activity is performed with an additional external load.

Level of Evidence:

III     

REDUCED HIP STRENGTH IS ASSOCIATED WITH INCREASED HIP MOTION DURING RUNNING IN YOUNG ADULT AND ADOLESCENT MALE LONG‐DISTANCE RUNNERS

Study Design:

Controlled laboratory study.

Background and Purpose:

Anterior knee pain is one of the most common running symptoms reported in the literature. While the exact etiology is unknown, a lack of hip strength is suggested to contribute to abnormal running mechanics. The purpose of this research study was to evaluate the association between isokinetic hip strength and 3‐D running kinematics.

Methods:

33 male high school and collegiate cross country runners participated in this study. Peak isokinetic hip abductor and hip extensor strength were assessed. Each subject also completed a treadmill running protocol at a self‐selected speed (mean = 3.8 m/s). 3‐D kinematic data were collected at 240 Hz using a 10‐camera motion capture system. Pearson correlation coefficients were used to determine the relationship between hip strength and hip range of motion (ROM) during the stance phase of running (p<0.05).

Results:

Peak isokinetic hip extensor torque was inversely correlated with transverse plane hip ROM (r = −.387, p = .026) but was not significantly related to sagittal plane hip ROM or frontal plane hip ROM. Peak isokinetic hip abductor torque was inversely correlated with frontal plane hip ROM (r=−.462, p=.008) but was not significantly related to either sagittal plane hip ROM or transverse plane hip ROM. Peak isokinetic hip extensor torque and peak isokinetic hip abductor torque were not significantly related to knee kinematics in any plane.

Conclusions:

Peak isokinetic hip extensor torque and peak isokinetic hip abductor torque are associated with transverse plane and frontal plane hip kinematics, but not knee kinematics.

Levels of Evidence:

Level 3b     

RELATIONSHIP BETWEEN HIP STRENGTH AND TRUNK,HIP, AND KNEE KINEMATICS DURING A JUMP‐LANDING TASK IN INDIVIDUALS WITH PATELLOFEMORAL PAIN

Background/Purpose:

Decreased strength of the hip musculature and altered mechanics of the lower extremity have been identified in individuals with patellofemoral pain (PFP). The aim of this study was to determine if a relationship exists between hip muscle strength and transverse and frontal plane motion at the hip and knee, and ipsilateral trunk flexion during a jump‐landing task in individuals with PFP.

Methods:

Fifteen individuals (10 females, 5 males) with PFP participated in this investigation. A three‐dimensional motion analysis system was utilized to assess trunk, hip, and knee kinematics during a jump‐landing task. An isokinetic dynamometer was utilized to assess concentric and eccentric strength of the hip musculature. Simple correlation analyses were performed to determine the relationships between hip muscle strength and peak frontal and transverse plane hip and knee kinematics and ipsilateral trunk flexion.

Results:

Decreased eccentric strength of the hip external rotators and abductors was significantly correlated to increased frontal plane motion at the hip and trunk, respectively (P<0.05).

Conclusions:

Based on these findings, eccentric strengthening exercises for the hip musculature may be an important component for clinicians to include when rehabilitating individuals with PFP who display increased frontal plane motion at the hip and trunk.

Level of Evidence:

2b     

CLINICAL EXAMINATION AND PHYSICAL ASSESSMENT OF HIP JOINT‐RELATED PAIN IN ATHLETES

Evidence‐based clinical examination and assessment of the athlete with hip joint related pain is complex. It requires a systematic approach to properly differentially diagnose competing potential causes of athletic pain generation. An approach with an initial broad focus (and hence use of highly sensitive tests/measures) that then is followed by utilizing more specific tests/measures to pare down this imprecise differential diagnosis list is suggested. Physical assessment measures are then suggested to discern impairments, activity and participation restrictions for athletes with hip‐join related pain, hence guiding the proper treatment approach.

Level of Evidence:

5     

CAN PROXIMAL HIP STRENGTH AND DYNAMIC CONTROL DIFFERENTIATE FUNCTIONAL ANKLE STABILITY CLASSIFICATIONS?

Background:Ankle instability can be problematic in an active population with multiple risk factors associated with recurrence.Purpose:The aim of this study was to determine if deficits in weight-bearing and non-weight bearing assessment of hip strength or dynamic balance in lower extremity reaching tasks from flat and inclined surfaces can differentiate subjects classified as controls, ankle sprain copers, or those with chronic, recurrent ankle sprains.Study Design:Quasiexperimental, Ex post factoMethods:A convenience sample of 60 subjects was classified into control, coper, or chronic ankle sprain groups based on the results of the Identification of Functional Ankle Instability Questionnaire. Subjects were tested for peak force production of their hip extensors, hip abductors, and a composite of hip extension and external rotation while in a standing position using a hand-held dynamometer. Additionally, each subject performed a modified Star Excursion Balance Test in anterior, posterolateral, and posteromedial directions from both a flat and 15 ° inverted stance position. One-way analysis of variance was calculated for between group differences of hip strength and balance reach ability and ankle stability classification. Pearson product-moment correlation coefficients were derived to evaluate relationships between hip strength and dynamic balance tests.Results:Twenty-one subjects were assigned to the control group, 23 to the coper group, and 16 to the chronic group. There were no significant differences between groups in self-report of Foot and Ankle Ability Measures or Tegner activity levels. Mean hip strength was not significantly different between ankle sprain classification groups (p = 0.66 – 0.82). The mean limb symmetry index for hip strength comparing injured and uninjured ankles was nearly symmetrical in all ankle stability groups (p = 0.34 – 0.97). The same symmetry was present when comparing injured and uninjured abilities for all dynamic balance reach tasks from both flat and inclined surfaces. (p = 0.16 – 0.62). There was a fair relationship between hip extension and weight-bearing hip extension/external rotation strength and the posteromedial and posterolateral reach tasks with correlation coefficients in the range of 0.33 – 0.43.ConclusionPerformance measures of tri-planar, static, isometric hip strength and lower extremity reach in dynamic balance tasks could not differentiate subjects without a history of injury from those subjects with one or more lateral ligamentous ankle sprains.Level Of Evidence:2b; Ex post facto     

MUSCLE ACTIVITY DURING KNEE‐EXTENSION STRENGTHENING EXERCISE PERFORMED WITH ELASTIC TUBING AND ISOTONIC RESISTANCE

Background/Purpose:

While elastic resistance training, targeting the upper body is effective for strength training, the effect of elastic resistance training on lower body muscle activity remains questionable. The purpose of this study was to evaluate the EMG‐angle relationship of the quadriceps muscle during 10‐RM knee‐extensions performed with elastic tubing and an isotonic strength training machine.

Methods:

7 women and 9 men aged 28‐67 years (mean age 44 and 41 years, respectively) participated. Electromyographic (EMG) activity was recorded in 10 muscles during the concentric and eccentric contraction phase of a knee extension exercise performed with elastic tubing and in training machine and normalized to maximal voluntary isometric contraction (MVC) EMG (nEMG). Knee joint angle was measured during the exercises using electronic inclinometers (range of motion 0‐90°).

Results:

When comparing the machine and elastic resistance exercises there were no significant differences in peak EMG of the rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM) during the concentric contraction phase. However, during the eccentric phase, peak EMG was significantly higher (p<0.01) in RF and VM when performing knee extensions using the training machine. In VL and VM the EMG‐angle pattern was different between the two training modalities (significant angle by exercise interaction). When using elastic resistance, the EMG‐angle pattern peaked towards full knee extension (0°), whereas angle at peak EMG occurred closer to knee flexion position (90°) during the machine exercise. Perceived loading (Borg CR10) was similar during knee extensions performed with elastic tubing (5.7±0.6) compared with knee extensions performed in training machine (5.9±0.5).

Conclusion:

Knee extensions performed with elastic tubing induces similar high (>70% nEMG) quadriceps muscle activity during the concentric contraction phase, but slightly lower during the eccentric contraction phase, as knee extensions performed using an isotonic training machine. During the concentric contraction phase the two different conditions displayed reciprocal EMG‐angle patterns during the range of motion.

Level of Evidence:

5     

HIP1基因沉默对人食管癌EC109细胞迁移侵袭能力的影响

目的:研究亨廷顿蛋白相互作用蛋白1(Huntingtin interacting protein 1,HIP1)基因沉默对人食管癌EC109细胞迁移侵袭的影响。方法:构建慢病毒干扰HIP1的食管癌细胞系,定量PCR和蛋白质印迹法检测HIP1基因沉默效果。通过细胞划痕实验和Transwell迁移侵袭试验研究HIP1基因沉默对人食管癌细胞迁移侵袭能力的影响。结果:慢病毒转染EC109食管癌细胞后,HIP1基因沉默效率达到80%以上。qRT-PCR和蛋白质印迹法证实此次慢病毒干扰HIP1效果显著。细胞划痕试验和Transwell迁移侵袭试验显示HIP1基因沉默后可抑制EC109食管癌细胞的迁移和侵袭。结论:构建的HIP1干涉慢病毒表达载体可抑制HIP1基因和蛋白的表达,并可有效抑制EC109食管癌细胞迁移和侵袭,提示HIP1作为食管癌的差异蛋白,可能通过促进食管癌细胞的转移参与食管癌的发生发展。     

TRUNK AND HIP ELECTROMYOGRAPHIC ACTIVITY DURING SINGLE LEG SQUAT EXERCISES DO SEX DIFFERENCES EXIST?

Purpose/Background:

Researchers have identified sex‐differences in lower extremity muscle activation during functional activities that involve landing and cutting maneuvers. However, less research has been conducted to determine if muscle activation differences occur during rehabilitation exercises. The purpose of this investigation was to determine if sex‐differences exist for activation amplitudes of the trunk and hip muscles during four single leg squat (SLS) exercises.

Methods:

Eighteen males and 16 females participated. Surface electromyography (EMG) was used to determine muscle activity of the abdominal obliques (AO), lumbar extensors (LE), gluteus maximus (GMX), and gluteus medius (GM) during four SLS exercises. Data were expressed as a percentage of a maximum voluntary isometric contraction (% MVIC). A 2 X 4 mixed‐model analysis of variance with repeated measures was used to determine the interaction between sex and exercise on each muscle''s activity.

Results:

No interaction effect existed between sex and exercise. A main effect for sex existed for the GM and LE. On average, females generated 39% greater GM (27.6 ± 10.4 % MVIC versus 19.8 ± 10.5 % MVIC) and 40% greater LE (8.0 ± 2.8 % MVIC versus 5.7 ± 2.8 % MVIC) activity than males. All subjects, regardless of sex, demonstrated similar GMX and AO activity. Overall EMG values ranged from 11.0 % MVIC to 14.7 % MVIC for the GMX and 5.7 % MVIC to 8.8 % MVIC for the AO.

Conclusions:

None of the subjects generated sufficient EMG activity for strength gains. Females generated a moderate level of GM activity appropriate for neuromuscular re‐education/endurance. Males generated a low level of GM activity that may not necessarily be sufficient to improve GM function. Subjects exhibited low levels of EMG activity for the other muscles. These findings suggest that clinicians modify and/or prescribe different exercises than those studied herein for the purpose of improving GM, GMX, AO, and LE function.

Level of Evidence:

3b     

单克隆抗体HIP2对人CFU—GM及CFU—AML体外作用的研究

刺激型抗人血小板单克隆抗体－ＨＩＰ２在体外有刺激人造血祖细胞集落形成的作用，本研究结果显示：ＨＩＰ２对正常人和急性髓系白血病初诊及缓解患的粒单系造血祖细胞集落产率有明显刺激作用，而对ＡＭＬ祖细胞集落产率无明显刺激作用，为临床ＡＭＬ患在化疗抑制期及骨髓移植造血抑制期用该抗体加速造血恢复提供了实验依据。     

PRE‐OPERATIVE LOW BACK PAIN NEGATIVELY AFFECTS SELF‐REPORTED FUNCTION IN INDIVIDUALS UNDERGOING HIP ARTHROSCOPY

Background/Purpose

Low back pain (LBP) is a common source of disability in adults and highly prevalent in patients with painful hip pathology. Persistent LBP after hip arthroplasty is associated with lower self‐reported function, however, the effect of pre‐operative LBP in patients undergoing hip arthroscopy for FAI has not been evaluated. The purpose of this study was to determine whether improvements in self‐reported hip function following arthroscopic surgery for femoroacetabular impingement (FAI) differed between those with and without reports of pre‐operative low back pain.

Study Design

Cohort

Methods

Three hundred eighteen subjects undergoing primary hip arthroscopy for clinically and radiographically‐confirmed FAI were recruited and consented. One hundred fifty‐six of these subjects completed the International Hip Outcomes Tool (iHOT‐33) and the Hip Outcome Score Activities of Daily Living Subscale (HOS‐ADL) before, and six and 12 months after surgery. Subjects were grouped based on the self‐reported presence or absence of LBP prior to arthroscopy. A repeated measures analysis of variance was used to determine the effects of time and low back pain on iHOT‐33 and HOS‐ADL scores.

Results

Seventy‐five of 156 subjects (48.1%) reported LBP prior to surgery. A main effect of time was found for both outcome measures (p<0.001), demonstrating improvement in self‐reported outcomes over the testing period. There was a main effect of group for the iHOT‐33 (LBP: 52.0 [47.9,56.0]; no LBP 57.9 [53.9,61.8]; p = 0.043) but not for the HOS‐ADL (LBP: 75.2 [72.2,78.2]; no LBP 78.8 [75.9,81.7]; p = 0.088) indicating that subjects with pre‐operative LBP had poorer self‐reported function per the iHOT‐33 compared to those without LBP.

Conclusion

Self‐reported hip function scores improved regardless of the presence of pre‐operative LBP; however subjects with LBP reported poorer self‐reported function per the iHOT‐33 as compared to those without LBP up to 12 months post‐operatively.

Level of Evidence

3c     

RADIOLOGICAL EXAMINATION OF THE HIP ‐ CLINICAL INDICATIONS,METHODS, AND INTERPRETATION: A CLINICAL COMMENTARY

There is a growing interest in musculoskeletal rehabilitation for young active individuals with non‐arthritic hip pathology. History and physical examination can be useful to classify those with non‐arthritic intra‐articular hip pathology as having impingement or instability. However, the specific type of deformity leading to symptoms may not be apparent from this evaluation, which may compromise the clinical decision‐making. Several radiological indexes have been described in the literature for individuals with non‐arthritic hip pathology. These indexes identify and quantify acetabular and femoral deformities that may contribute to instability and impingement. The aim of this paper is to discuss clinical indications, methods, and the use of hip radiological images or radiology reports as they relate to physical examination findings for those with non‐arthritic hip pathology.

Level of evidence:

5     

RELIABILITY OF VIDEO‐BASED QUANTIFICATION OF THE KNEE‐ AND HIP ANGLE AT FOOT STRIKE DURING RUNNING

Introduction:

In clinical practice, joint kinematics during running are primarily quantified by two‐dimensional (2D) video recordings and motion‐analysis software. The applicability of this approach depends on the clinicians’ ability to quantify kinematics in a reliable manner. The reliability of quantifying knee‐ and hip angles at foot strike is uninvestigated.

Objective:

To investigate the intra‐ and inter‐rater reliability within and between days of clinicians’ ability to quantify the knee‐ and hip angles at foot strike during running.

Methods:

Eighteen recreational runners were recorded twice using a clinical 2D video setup during treadmill running. Two blinded raters quantified joint angles on each video twice with freeware motion analysis software (Kinovea 0.8.15)

Results:

The range from the lower prediction limit to the upper prediction limit of the 95% prediction interval varied three to eight degrees (within day) and nine to 14 degrees (between day) for the knee angles. Similarly, the hip angles varied three to seven degrees (within day) and nine to 11 degrees (between day).

Conclusion:

The intra‐ and inter rater reliability of within and between day quantifications of the knee‐ and hip angle based on a clinical 2D video setup is sufficient to encourage clinicians to keep using 2D motion analysis techniques in clinical practice to quantify the knee‐ and hip angles in healthy runners. However, the interpretation should include critical evaluation of the physical set‐up of the 2D motion analysis system prior to the recordings and conclusions should take measurement variations (3‐8 degrees and 9‐14 degrees for within and between day, respectively) into account.

Level of evidence:

3     

COMPARISON OF TRUNK AND LOWER EXTREMITY MUSCLE ACTIVITY AMONG FOUR STATIONARY EQUIPMENT DEVICES: UPRIGHT BIKE,RECUMBENT BIKE,TREADMILL, AND ELLIPTIGO?

Background

Stationary equipment devices are often used to improve fitness. The ElliptiGO® was recently developed that blends the elements of an elliptical trainer and bicycle, allowing reciprocal lower limb pedaling in an upright position. However, it is unknown whether the muscle activity used for the ElliptiGO® is similar to walking or cycling. To date, there is no information comparing muscle activity for exercise on the treadmill, stationary upright and recumbent bikes, and the ElliptiGO®.

Purpose/Hypothesis

The purpose of this study was to assess trunk and lower extremity muscle activity among treadmill walking, cycling (recumbent and upright) and the ElliptiGO® cycling. It was hypothesized that the ElliptiGO® and treadmill would elicit similar electromyographic muscle activity responses compared to the stationary bike and recumbent bike during an exercise session.

Study Design

Cohort, repeated measures

Methods

Twelve recreationally active volunteers participated in the study and were assigned a random order of exercise for each of the four devices (ElliptiGO®, stationary upright cycle ergometer, recumbent ergometer, and a treadmill). Two-dimensional video was used to monitor the start and stop of exercise and surface electromyography (SEMG) were used to assess muscle activity during two minutes of cycling or treadmill walking at 40-50% heart rate reserve (HRR). Eight muscles on the dominant limb were used for analysis: gluteus maximus (Gmax), gluteus medius (Gmed), biceps femoris (BF), lateral head of the gastrocnemius (LG), tibialis anterior (TA), rectus femoris (RF). Two trunk muscles were assessed on the same side; lumbar erector spinae at L3-4 level (LES) and rectus abdominus (RA). Maximal voluntary isometric contractions (MVIC) were determined for each muscle and SEMG data were expressed as %MVIC in order to normalize outputs.

Results

The %MVIC for RF during ElliptiGO® cycling was higher than recumbent cycling. The LG muscle activity was highest during upright cycling. The TA was higher during walking compared to recumbent cycling and ElliptiGO® cycling. No differences were found among the the LES and remaining lower limb musculature across devices.

Conclusion

ElliptiGO® cycling was found to elicit sufficient muscle activity to provide a strengthening stimulus for the RF muscle. The LES, RA, Gmax, Gmed, and BF activity were similar across all devices and ranged from low to moderate strength levels of muscle activation. The information gained from this study may assist clinicians in developing low to moderate strengthening exercise protocols when using these four devices.

Level of evidence

3     

REGIONAL INTERDEPENDENCE OF THE HIP AND LUMBO‐PELVIC REGION IN DIVISON II COLLEGIATE LEVEL BASEBALL PITCHERS: A PRELIMINARY STUDY

Background

Pitchers may be at greater risk of injury in comparison to other overhead throwing athletes due to the repetition of the pitching motion. It has been reported that approximately 30% of all baseball injuries occur in the lower body. This may be related to limited hip mobility, which can compromise pitching biomechanics while placing excessive stress on the trunk and upper quarter. Hip motion and strength measurements have been reported in professional baseball pitchers but have not been reported in collegiate pitchers.

Purpose

The purpose of this study was to report preliminary findings for passive hip motion and isometric hip muscle strength in collegiate pitchers and compare them to previously published values for professional level pitchers.

Study Design

Cross sectional study

Methods

Twenty‐nine collegiate baseball pitchers (age = 20.0 + 1.4 years, height = 1.88 + 0.06 m; weight = 89.3 + 10.7 kg; body mass index = 25.3 + 2.5 kg/m2) were recruited. Subjects were assessed for hip internal rotation (IR) and external rotation (ER) passive motion, hip anteversion or retroversion, gluteus maximus, gluteus medius, hip internal rotator, hip external rotator strength, and lumbo‐pelvic control with the prone active hip rotation test as described by Sahrmann. Statistical analysis included calculation of subject demographics (means and SD) and use of a two‐tailed t‐test (p >0.05).

Results

Fifty‐two percent of the right‐handed and 50% of the left‐handed pitchers demonstrated poor lumbo‐pelvic motor control with an inability to stabilize during active hip IR and ER even though isolated strength deficits were not detected at a significant level. There were no significant differences in hip passive motion or gluteus medius strength between right and left‐handed pitchers. Differences did exist between collegiate data and previously published values for professional pitchers for IR motion measured in prone and gluteus maximus strength. Hip retroversion was present in 55% of the pitchers primarily in both limbs with four of the pitchers presenting with retroversion singularly in either the stride or trail limb where the ER rotation motion was greater than the IR.

Conclusion

Assessing mobility and muscle strength of the lower quarter in isolation can be misleading and may not be adequate to ensure the potential for optimal pitching performance. These findings suggest that lumbo‐pelvic control in relation to the lower extremities should be assessed as one functional unit. This is the first study to explore hip motion, strength, and lumbo‐pelvic control during active hip rotation in collegiate baseball pitchers.

Evidence Level

2