STUDY DESIGN: Randomized, double-blind, parallel-group clinical trial. OBJECTIVES: To assess differences between a progressive agility and trunk stabilization rehabilitation program and a progressive running and eccentric strengthening rehabilitation program in recovery characteristics following an acute hamstring injury, as measured via physical examination and magnetic resonance imaging (MRI). BACKGROUND: Determining the type of rehabilitation program that most effectively promotes muscle and functional recovery is essential to minimize reinjury risk and to optimize athlete performance. METHODS: Individuals who sustained a recent hamstring strain injury were randomly assigned to 1 of 2 rehabilitation programs: (1) progressive agility and trunk stabilization or (2) progressive running and eccentric strengthening. MRI and physical examinations were conducted before and after completion of rehabilitation. RESULTS: Thirty-one subjects were enrolled, 29 began rehabilitation, and 25 completed rehabilitation. There were few differences in clinical or morphological outcome measures between rehabilitation groups across time, and reinjury rates were low for both rehabilitation groups after return to sport (4 of 29 subjects had reinjuries). Greater craniocaudal length of injury, as measured on MRI before the start of rehabilitation, was positively correlated with longer return-to-sport time. At the time of return to sport, although all subjects showed a near-complete resolution of pain and return of muscle strength, no subject showed complete resolution of injury as assessed on MRI. CONCLUSION: The 2 rehabilitation programs employed in this study yielded similar results with respect to hamstring muscle recovery and function at the time of return to sport. Evidence of continuing muscular healing is present after completion of rehabilitation, despite the appearance of normal physical strength and function on clinical examination. LEVEL OF EVIDENCE: Therapy, level 1b–.

J Orthop Sports Phys Ther 2013;43(5):284-299. Epub 13 March 2013. doi:10.2519/jospt.2013.4452

KEY WORDS: MRI, muscle, return-to-sport criteria

STUDY DESIGN: Resident’s case problem. BACKGROUND: A 56-year-old man was referred to physical therapy for analysis of unusual gait, first noticed 3 years previously when running. Prior to this evaluation, the patient had seen multiple orthopaedic, sports medicine, and neurological specialists while undergoing repeated and extensive testing. Ten months of testing and treatment, including conservative and surgical management, did not provide an explanation for the gait abnormality or result in improvement of the patient’s condition. DIAGNOSIS: The patient’s physical examination was relatively unremarkable, considering the severity of the gait abnormality. Distinct abnormalities were apparent with computerized gait analysis and dynamic electromyography, and, when combined with the physical examination findings, led to a suspicion of the task-specific disorder of runner’s dystonia. The patient was referred to a neurologist specializing in movement-related disorders, with a final confirmed diagnosis of primary task-specific dystonia with first onset during running (ie, runner’s dystonia). DISCUSSION: Idiopathic, task-specific dystonia of the lower extremity is documented as a very rare occurrence, yet increasing trends in running participation may result in a higher incidence of this condition. Improved awareness of runner’s dystonia in the present case might have enhanced the clinical decision-making process and resulted in more timely and effective treatment solutions. Clinical examination findings, including computerized gait analysis and electromyography, in conjunction with imaging, blood, and genetic testing, can aid in the diagnosis of runner’s dystonia. LEVEL OF EVIDENCE: Differential diagnosis, level 4.

J Orthop Sports Phys Ther 2012;42(8):688-697, Epub 20 April 2012. doi:10.2519/jospt.2012.3892

KEY WORDS: differential diagnosis, electromyography, gait analysis, runner’s dystonia

STUDY DESIGN: Case report. BACKGROUND: Postpartum low back and hip dysfunction may be caused by an incomplete recovery of abdominal musculature and impaired neuromuscular control. The purpose of this report is to describe the management of a postpartum runner with hip and low back pain through exercise training via ultrasound imaging (USI) biofeedback combined with running-form modification. CASE DESCRIPTION: A postpartum runner with hip and low back pain underwent dynamic lumbar stabilization training with USI biofeedback and running-form modification to reduce mechanical loading. Muscle thickness of transversus abdominis and internal oblique was measured with USI preintervention and 7 weeks after completion of the intervention. Additionally, 3-dimensional lower extremity joint motions, moments, and powers were calculated during treadmill running. OUTCOMES: The patient's pain with running decreased from a constant 9/10 (0, no pain; 10, worst pain) to an occasional 3/10 posttreatment. Transversus abdominis muscle thickness increased 6.3% during the abdominal drawing-in maneuver and 27.0% during the abdominal drawing-in maneuver with straight leg raise. Changes were also noted in the internal oblique. These findings corresponded to improved lumbopelvic control: pelvic list and axial rotation during running decreased 38% and 36%, respectively. The patient's running volume returned to preinjury levels (8.1-9.7 km, 3 days per week) with no hip pain and minimal low back pain, and she successfully completed her goal of running a half-marathon. DISCUSSION: The successful outcomes of this case support the consideration of dynamic lumbar stabilization exercises, USI biofeedback, and running-form modification in postpartum runners with lumbopelvic dysfunction. LEVEL OF EVIDENCE: Therapy, level 4.

J Orthop Sports Phys Ther 2012;42(7):615-624, Epub 23 March 2012. doi:10.2519/jospt.2012.3941

KEY WORDS: abdominal drawing-in maneuver, pregnancy, running mechanics, transversus abdominis

For physical therapists, modifying technique is not a novel concept; however, our motives are typically focused on symptom and injury reduction rather than purely performance. These specific modifications are based on minimizing tissue load, while still enabling successful completion of the task. Applying this same rationale to running, an activity in which up to 80% of participants are injured annually, would seem to be a good thing. Yet the idea of using gait retraining in patients without neurological injury/pathology is rather uncommon. However, a few researchers have investigated specific walking retraining strategies to reduce knee joint loading, with the goal of applying these techniques to individuals with knee osteoarthritis. This has led some to use the same concept on runners with patellofemoral pain, with a corresponding improvement in gait and symptoms.

J Orthop Sports Phys Ther 2011;41(12):909-910. doi:10.2519/jospt.2011.0111

KEY WORDS: 2012 Olympic Games, running

Patellofemoral pain and iliotibial band syndromes continue to puzzle and oftentimes frustrate both patients and clinicians alike. While a myriad of treatments, including footwear, orthoses, bracing, patellar taping, and quadriceps strengthening, have been traditionally promoted and sometimes shown to be moderately effective, improvements in symptoms and function are not universal. In recent years, a trend toward consideration of more proximal influences on knee injuries (ie, lumbopelvic and hip regions) has continued to grow as insights are gained into this potential mechanism. However, the specific cause-effect relationship is not as clear as we might anticipate. This special issue of the Journal provides a compilation of papers focused on further defining the contribution of proximal factors to knee/lower extremity injury. Collectively, we hope these papers will provide direction to both patient care and patient-related research.

J Orthop Sports Phys Ther 2010;40(2):39-41. doi:10.2519/jospt.2010.0102

KEY WORDS: hip, iliotibial band syndrome, knee, patellofemoral pain syndrome

SYNOPSIS: Hamstring strain injuries remain a challenge for both athletes and clinicians, given their high incidence rate, slow healing, and persistent symptoms. Moreover, nearly one third of these injuries recur within the first year following a return to sport, with subsequent injuries often being more severe than the original. This high reinjury rate suggests that commonly utilized rehabilitation programs may be inadequate at resolving possible muscular weakness, reduced tissue extensibility, and/or altered movement patterns associated with the injury. Further, the traditional criteria used to determine the readiness of the athlete to return to sport may be insensitive to these persistent deficits, resulting in a premature return. There is mounting evidence that the risk of reinjury can be minimized by utilizing rehabilitation strategies that incorporate neuromuscular control exercises and eccentric strength training, combined with objective measures to assess musculotendon recovery and readiness to return to sport. In this paper, we first describe the diagnostic examination of an acute hamstring strain injury, including discussion of the value of determining injury location in estimating the duration of the convalescent period. Based on the current available evidence, we then propose a clinical guide for the rehabilitation of acute hamstring injuries, including specific criteria for treatment progression and return to sport. Finally, we describe directions for future research, including injury-specific rehabilitation programs, objective measures to assess reinjury risk, and strategies to prevent injury occurrence. LEVEL OF EVIDENCE: Diagnosis/therapy/prevention, level 5.

J Orthop Sports Phys Ther 2010;40(2):67-81, Epub 14 January 2010. doi:10.2519/jospt.2010.3047

KEY WORDS: functional rehabilitation, muscle strain injury, radiology/medical imaging, running, strength training

STUDY DESIGN: Case report. BACKGROUND: Clinical practice guidelines regarding the conservative management of degenerative hip conditions in older adults routinely incorporate therapeutic exercise and manual therapy. However, the application of these recommendations to young, active adults is less clear. The purpose of this case report is to describe the management of a young adult with advanced hip arthrosis using a multifaceted rehabilitation program. CASE DESCRIPTION: A 28-year-old female with severe left hip degeneration, as identified with diagnostic imaging, was referred to physical therapy. Reduced hip range of motion and strength, sacroiliac joint asymmetries, and a modified Harris Hip Score of 76 were observed. She was seen for 12 visits over a 3-month period and treated with an individualized program including manual therapy, therapeutic exercise, and neuromuscular re-education. OUTCOME: Substantial improvements were noted in pain, hip range of motion, and strength and function (modified Harris Hip Score of 97). In addition, she discontinued the use of anti-inflammatory medications and returned to her prior level of activity. Improvements were maintained at a 3-month follow-up, with symptom recurrence managed using a self-mobilization technique to the left hip and massage to the left iliopsoas. DISCUSSION: Degenerative hip conditions are common among older adults but are relatively rare in the younger population. Although it is likely that this patient will experience a return of her symptoms and functional limitations as her hip disease progresses, the immediate improvements may delay the need for eventual surgical management. These outcomes suggest that physical therapy management should be considered in those with an early onset of degenerative hip disease and are consistent with results previously reported in the older population. LEVEL OF EVIDENCE: Therapy, level 4.

J Orthop Sports Phys Ther 2009;39(12):858-866. doi:10.2519/jospt.2009.3207

KEY WORDS: manual therapy, OA, osteoarthritis, therapeutic exercise

STUDY DESIGN: A case-control study, with single observation. OBJECTIVES: To compare the onset timing and activation of the vastus medialis oblique (VMO) and vastus lateralis (VL) between subjects with and without patellofemoral pain syndrome (PFPS) at various step heights. BACKGROUND: It has been theorized that delayed or reduced VMO activity relative to the VL contributes to lateral patellar tracking and PFPS. However, conflicting evidence exists in the literature regarding this proposed mechanism. The lack of agreement among studies may be attributed to inconsistent knee flexion angles used in previous studies. METHODS AND MEASURES: Twenty subjects with PFPS (mean ± SD age, 29.5 ± 10 yrs) and 20 control subjeccts (mean ± SD age, 25.4 ± 3.1 yrs) ascended 5 different step heights, while knee kinematics and quadriceps EMG data were collected. Knee flexion angle at foot-step contact, VMO-VL onset timing, and VMO/VL activation ratios were analyzed between groups and step heights using 2-factor analyses of variance (ANOVAs) with repeated measures (α = .05). RESULTS: Individuals with PFPS demonstrated 4.7° (P = .038) more knee flexion at foot-step contact than control subjects. Despite greater knee flexion with increased step height (P‹.001), no differences in onset timing or activation magnitude ratio were present between groups or across step heights. However, individuals with PFPS displayed a significantly increased activation duration ratio compared to the control group (P = .043). CONCLUSION: Quadriceps onset timing and activation magnitude during stair ascent was similar between individuals with and without PFPS, regardless of step height. Thus, the results of this study are in agreement with evidence indicating no difference in VMO-VL timing and VMO/VL activation magnitude ratio between individuals with and without PFPS.

J Orthop Sports Phys Ther. 2007;37(5):239-244; published online 15 March 2007. doi:10.2519/jospt.2007.2421

KEY WORDS: activation ratio, anterior knee pain, EMG, onset delay, stair climbing

STUDY DESIGN: Prospective cohort. OBJECTIVE: To determine (1) the cumulative seasonal incidence and overall injury rate of medial tibial stress syndrome (MTSS) and (2) risk factors for MTSS with a primary focus on the relationship between navicular drop values and MTSS in high school cross-country runners. BACKGROUND: MTSS is a common injury among runners. However, few studies have reported the injury rate and risk factors for MTSS among adolescent runners. METHODS AND MEASURES: Data collected included measurement of bilateral navicular drop and foot length, and a baseline questionnaire regarding the runner’s height, body mass, previous running injury, running experience, and orthotic or tape use. Runners were followed during the season to determine athletic exposures (AEs) and occurrence of MTSS. RESULTS: The overall injury rate for MTSS was 2.8/1000 AEs. Although not statistically different, girls had a higher rate (4.3/1000 AEs) than boys (1.7/1000 AEs) (P = .11). Logistic regression modeling indicated that only gender and body mass index (BMI) were significantly associated with the occurrence of MTSS. However, when controlled for orthotic use, only BMI was associated with risk of MTSS. No significant associations were found between MTSS and navicular drop or foot length. CONCLUSIONS: Our findings suggest that navicular drop may not be an appropriate measure to identify runners who may develop MTSS during a cross-country season; thus, additional studies are needed to identify appropriate preseason screening tools.  

J Orthop Sports Phys Ther. 2007;37(2):40-47. doi:10.2519/jospt.2007.2343 

KEY WORDS: injury risk, female athlete, navicular drop, shin splints

Study Design: Two-group posttest-only comparison. Objective: To assess the influence of the Q-angle on the 3-dimensional lower extremity kinematics during running. Background: An excessive Q-angle has been implicated in the development of knee injuries by altering the lower extremity locomotion kinematics. Previous investigations using 2-dimensional analyses during walking did not support this hypothesis. Methods and Measures: We hypothesized that individuals with Q-angles more than 15° would display an increase in rearfoot eversion and tibial internal rotation during running. Thirty-two nonimpaired subjects (men: n = 16, mean age = 22 ± 3 years; women: n = 16, mean age = 23 ± 3 years) ran over ground, and 3-dimensional kinematic data were collected from the right lower extremity. Subjects with a Q-angle of 15° or less comprised the low-Q-angle group, whereas those with Q-angles of more than 15° comprised the high-Q-angle group. Segment and joint maximum angles and the times when the maxima occurred during stance were measured. Results: The Q-angle magnitude did not increase the maximum segment or joint angles during running. The groups displayed similar maximum angles for rearfoot eversion (low Q-angle, -15.5 ± 5.0°; high Q-angle, -15.6 ± 6.6°) and tibial internal rotation (low Q-angle, -8.8 ± 4.8°; high Q-angle, -6.8 ± 5.1°). The high-Q-angle group (39.5 ± 16.3%) achieved maximum tibial internal rotation later in the stance phase than the low-Q-angle group (28.8 ± 10.7%). Conclusions: In support of the previous investigations involving Q-angle influences on kinematics, our study did not reveal any differences between groups in maximum joint or segment angles. The kinematic information did reveal that the high-Q-angle group displayed an increase in time to maximum tibial internal rotation. The impact of this single factor on producing knee injury is unknown.

J Orthop Sports Phys Ther. 2000;30(5):271-278.

Key Words: segment alignment, 3-dimensional kinematics, tibial rotation

Due to increasing emphasis on closed kinetic chain exercises in rehabilitation, there is a need to objectively quantify their effectiveness. The purpose of this study was to determine the test-retest reliability of the peak force and total work scores during a concentric isokinetic leg press pattern using the Lido Linea closed kinetic chain isokinetic dynamometer. The static calibration of force measurements was established by hanging a series of certified weights from a lever arm of known length affixed to the system's force measurement shafts. A repeated-trials, multiple-day experimental paradigm was utilized to establish the static calibration procedure's reliability. No significant difference was found between expected and observed force scores (p > .05). Thirty healthy, active subjects (22.5 ± 3.9 years) performed concentric isokinetic leg press exercise under maximal voluntary conditions across a velocity spectrum of 25.4, 50.8, and 76.2 cm/sec (10, 20, and 30 inch/sec) in a test-retest experimental paradigm, separated by 24-72 hours. Intraclass correlation coefficient values (ICC 2,1) across Day 1 and Day 2 for peak force and total work ranged from 0.87 to 0.94 (p < .05). The data indicate that the Lido Linea closed kinetic chain isokinetic dynamometer is an appropriate instrument for assessing concentric isokinetic performance during a closed kinetic chain leg press pattern.

J Orthop Sports Phys Ther. 1997;25(2):133-136.

Key Words: muscle strength, reliability, closed kinetic chain

Plyometric training has become a popular training and rehabilitation tool. The purpose of this study was to compare the effects of plyometric and isokinetic concentric/eccentric training of the shoulder internal rotators. Female subjects (N = 78) were randomly assigned to 3 groups: control, isokinetic training, and plyometric training. Pre-/posttesting measurements included: 1) concentric/eccentric isokinetic power measurements of the shoulder internal rotators at 60°/sec, 180°/sec, and 240°/sec; 2) kinesthetic measurements of shoulder internal rotation, external rotation < 45°, and external rotation > 45°; and 3) a softball distance test. Both groups trained twice a week for 8 weeks. Power and kinesthetic data were analyzed using multiple analyses of variance with repeated measures. A one-way analysis of variance was performed on the softball throw data. No significant (p < .05) pre-/posttest differences were found with kinesthetic testing or the softball throw. Pre-/postpower differences were significantly greater for the isokinetic group at 60°/sec eccentric, 120°/sec concentric and eccentric, and 240°/sec concentric and eccentric. Isokinetic training of the shoulder internal rotators increases isokinetic power, but neither isokinetic nor plyometric training resulted in a functional improvement with the softball throw.

J Orthop Sports Phys Ther. 1996;23(2):125-133.

Key Words: shoulder, resistive exercise, throwing