Clinical, Safety and Engineering Perspectives on Wearable Ultrasound Technology: A Review.

Wearable ultrasound has the potential to become a disruptive technology enabling new applications not only in traditional clinical settings, but also in settings where ultrasound is not currently used. Understanding the basic engineering principles and limitations of wearable ultrasound is critical for clinicians, scientists, and engineers to advance potential applications and translate the technology from bench to bedside. Wearable ultrasound devices, especially monitoring devices, have the potential to apply acoustic energy to the body for far longer durations than conventional diagnostic ultrasound systems. Thus, bioeffects associated with prolonged acoustic exposure as well as skin health need to be carefully considered for wearable ultrasound devices. This paper reviews emerging clinical applications, safety considerations, and future engineering and clinical research directions for wearable ultrasound technology.

MANAGEMENT OF ACUTE GRADE II LATERAL ANKLE SPRAINS WITH AN EMPHASIS ON LIGAMENT PROTECTION: A DESCRIPTIVE CASE SERIES.

BACKGROUND AND PURPOSE: Lateral ankle sprain the most common injury in physically active populations. Individuals who sustain an acute lateral ankle sprain may not receive timely formal rehabilitation and are at an increased risk to have subsequent sprains which can lead to chronic pain and instability. Attention to essential factors for ligament protection and healing while preserving ankle movement, may result in a more stable yet mobile ankle offering improved outcomes. The purpose of this case series was to describe the methods and observe the outcomes associated with a comprehensive strategy for managing acute first episode grade II lateral ankle sprains. STUDY DESIGN: Prospective case series. CASE DESCRIPTIONS AND INTERVENTIONS: Ten patients (mean age 26.7 years, range 16-51 years, mean 2.3 days from injury) with acute grade II lateral ankle sprain were treated with an approach to protect the injured ligament, prevent impairments to movement, restore strength and proprioception, and progress to full function. Patient outcomes were assessed at four, eight and 12 weeks. Follow-up interviews at six and 12 months assessed injury recurrence. OUTCOMES: Patients were treated for an average of eight sessions over a mean of seven weeks. Rapid change in self-reported function, ankle ROM, and pain were observed in the first four weeks of care. Clinically meaningful improvements in function and ankle ROM were also noted at eight weeks and maintained at 12-week follow-ups. All patients returned to desired physical activity with only a single re-sprain event within one year after injury. CONCLUSION: The results of this prospective case series suggest that a treatment approach designed to protect the injured ligament, maintain and restore normal ankle motion, and provide a tailored functional pathway to return to run and sport demonstrated resolution of symptoms and improvement in reported functional outcomes in a group of patients following grade II acute primary ankle sprain. LEVEL OF EVIDENCE: Level IV, Case Series.

Reliability of ultrasound shear-wave elastography in assessing low back musculature elasticity in asymptomatic individuals.

Patients with low back pain commonly exhibit impaired morphology and function of spinal musculature that may be quantifiable using shear-wave elastography (SWE). The purpose of this study was to assess the intra-rater and test-retest reliability of SWE elasticity measures of the lumbar erector spinae and multifidus muscles during rest and differing levels of contraction in asymptomatic individuals. This single-group repeated-measures design involved a baseline measurement session and a follow-up session 3 days later. The lumbar multifidus was imaged at rest and during three levels of contraction (minimal, moderate, and maximum). The lumbar erector spinae (illiocostalis and longissimus muscles) were imaged at rest only. Overall reliability estimates were fair to excellent with ICCs ranging from 0.44 to 0.92. Reliability was higher in the lumbar multifidus muscles than the erector spinae muscles, slightly higher during contraction than during rest, and substantially improved by using the mean of 3 measurements. By reliably quantifying impaired spinal musculature, SWE may facilitate an improved understanding of the etiology and treatment of low back pain and other muscle pain-related conditions such as trigger points and fibromyalgia.

Effects of dry needling to the symptomatic versus control shoulder in patients with unilateral subacromial pain syndrome.

BACKGROUND: Initial reports suggest that treating myofascial trigger points in the infraspinatus with dry needling may be effective in treating patients with shoulder pain. However, to date, high quality clinical trials and thorough knowledge of the physiologic mechanisms involved is lacking. OBJECTIVES: To examine the effect of dry needling to the infraspinatus muscle on muscle function, nociceptive sensitivity, and shoulder range of motion (ROM) in the symptomatic and asymptomatic shoulders of individuals with unilateral subacromial pain syndrome. DESIGN: Within-subjects controlled trial. METHODS: Fifty-seven volunteers with unilateral subacromial pain syndrome underwent one session of dry needling to bilateral infraspinatus muscles. Outcome assessments, including ultrasonic measures of infraspinatus muscle thickness, pressure algometry, shoulder internal rotation and horizontal adduction ROM, and questionnaires regarding pain and related disability were taken at baseline, immediately after dry needling, and 3-4 days later. RESULTS: Participants experienced statistically significant and clinically relevant changes in all self-report measures. Pressure pain threshold and ROM significantly increased 3-4 days, but not immediately after dry needling only in the symptomatic shoulder [Pressure pain threshold: 5.1 (2.2, 8.0) N/cm2, internal rotation ROM: 9.6 (5.0, 14.1) degrees, horizontal adduction ROM: 5.9 (2.5, 9.4) degrees]. No significant changes occurred in resting or contracted infraspinatus muscle thickness in either shoulder. CONCLUSIONS: This study found changes in shoulder ROM and pain sensitivity, but not in muscle function, after dry needling to the infraspinatus muscle in participants with unilateral subacromial pain syndrome. These changes generally occurred 3-4 days after dry needling and only in the symptomatic shoulders.

Manual Physical Therapy Following Immobilization for Stable Ankle Fracture: A Case Series.

STUDY DESIGN: Case series. BACKGROUND: Ankle fractures commonly result in persistent pain, stiffness, and functional impairments. There is insufficient evidence to favor any particular rehabilitation approach after ankle fracture. The purpose of this case series was to describe an impairment-based manual physical therapy approach to treating patients with conservatively managed ankle fractures. CASE DESCRIPTION: Patients with stable ankle fractures postimmobilization were treated with manual physical therapy and exercise targeted at associated impairments in the lower limb. The primary outcome measure was the Lower Extremity Functional Scale. Secondary outcome measures included the ankle lunge test, numeric pain-rating scale, and global rating of change. Outcome measures were collected at baseline (performed within 7 days of immobilization removal) and at 4 and 12 weeks postbaseline. OUTCOMES: Eleven patients (mean age, 39.6 years; range, 18-64 years; 2 male), after ankle fracture-related immobilization (mean duration, 48 days; range, 21-75 days), were treated for an average of 6.6 sessions (range, 3-10 sessions) over a mean of 46.1 days (range, 13-81 days). Compared to baseline, statistically significant and clinically meaningful improvements were observed in Lower Extremity Functional Scale score (P = .001; mean change, 21.9 points; 95% confidence interval: 10.4, 33.4) and in the ankle lunge test (P = .001; mean change, 7.8 cm; 95% confidence interval: 3.9, 11.7) at 4 weeks. These changes persisted at 12 weeks. DISCUSSION: Statistically significant and clinically meaningful improvements in self-reported function and ankle range of motion were observed at 4 and 12 weeks following treatment with impairment-based manual physical therapy. All patients tolerated treatment well. Results suggest that this approach may have efficacy in this population. LEVEL OF EVIDENCE: Therapy, level 4.

The reliability of rehabilitative ultrasound imaging in the measurement of infraspinatus muscle function in the symptomatic and asymptomatic shoulders of patients with unilateral shoulder impingement syndrome.

BACKGROUND: Rehabilitative ultrasound Imaging (RUSI) is increasingly used in the management of musculoskeletal conditions as it provides an objective measure of muscle function while being less invasive than needle electromyography. While research has documented the ability to reliably measure trunk muscles in patients with back pain, no study to date has used RUSI to quantify infraspinatus muscle function in patients with shoulder impingement syndrome (SIS). HYPOTHESIS/PURPOSE: The purpose of this study was to examine the intra-rater and inter-rater reliability of measuring infraspinatus muscle thickness with RUSI and to compare such measures during resting versus contracted muscle states and in the symptomatic versus asymptomatic shoulders in patients with SIS. STUDY DESIGN: Cross-sectional, measurement study. METHODS: Fifty-two participants with unilateral SIS underwent a standard baseline examination to include RUSI of the infraspinatus muscle bilaterally. Images were acquired at rest and during a submaximal isometric contraction, by two novice examiners. The isometric contraction was elicited by having prone participants externally rotate their shoulder from a position of 90° abduction into a dynamometer and hold a static force of 20 mmHg (approximately 20-30% maximal voluntary contraction). Images were captured using a standardized placement of the transducer placed just inferior to the spine of the scapula along the medial scapular border and measured off-line using Image J software (V1.38t, National Institutes of Health, Bethesda, Maryland). RESULTS: Estimates (ICCs) for thickness measurements ranged between 0.96 and 0.98 for intra-rater reliability and between 0.87 and 0.92 for inter-rater reliability. Reliability was substantially lower (ICC = 0.43 to 0.79) for calculations of percent thickness change. The infraspinatus muscle was significantly thicker when contracted (19.1mm) than during rest (16.2mm) in both shoulders (p < 0.001). There was also a statistically significant interaction between contraction state and shoulder (p = 0.026), indicating that the change in thickness that occurred during contraction was significantly smaller in the symptomatic shoulder than in the asymptomatic shoulder. CONCLUSION: RUSI measurements of infraspinatus muscle thickness appear to be highly reliable, both within the same examiner and between different examiners, in patients with SIS. Moreover, such measurements were different in rested and contracted states of the infraspinatus, as well as, between the symptomatic and asymptomatic shoulders of patients with unilateral SIS. LEVEL OF EVIDENCE: Level 2.

Suprascapular neuropathy after distal clavicle resection and coracoclavicular ligament reconstruction: a resident's case problem.

STUDY DESIGN: Resident's case problem. BACKGROUND: Acromioclavicular joint pathology is reported to be present in up to 30% of all patients complaining of shoulder dysfunction. The operative approach to treating acromioclavicular joint disease often includes a distal clavicle excision and, in circumstances of acromioclavicular joint instability, reconstruction of the coracoclavicular and/or the acromioclavicular ligament. Surgical complications for these procedures are rare, but potentially include suprascapular neuropathy secondary to the course of the suprascapular nerve posterior to the clavicle prior to entering the supraspinatus fossa. DIAGNOSIS: A 28-year-old Caucasian woman reported directly to an outpatient physical therapy clinic with a complaint of right shoulder weakness. Three years prior, the patient underwent a distal clavicle excision and coracoclavicular ligament reconstruction. A detailed examination, including diagnostic imaging, identified infraspinatus atrophy and weakness, increasing the suspicion for suprascapular nerve injury. Electromyography was ordered to confirm the clinical and imaging diagnosis of suprascapular neuropathy and to rule out other nerve lesions, especially considering the selective atrophy of the infraspinatus muscle without mechanical explanation. DISCUSSION: The clinical decision making and systematic use of diagnostic testing resulted in identifying a rare case of suprascapular neuropathy, selective to the infraspinatus, in a patient who previously underwent a distal clavicle excision and coracoclavicular ligament reconstruction. Without a spinoglenoid cyst or other suprascapular nerve lesion identified on advanced imaging, it is likely that the suprascapular neuropathy identified in this case was related to the surgical procedure. LEVEL OF EVIDENCE: Differential diagnosis, level 4.

Criterion validity of manual assessment of spinal stiffness.

Assessment of spinal stiffness is widely used by manual therapy practitioners as a part of clinical diagnosis and treatment selection. Although studies have commonly found poor reliability of such procedures, conflicting evidence suggests that assessment of spinal stiffness may help predict response to specific treatments. The current study evaluated the criterion validity of manual assessments of spinal stiffness by comparing them to indentation measurements in patients with low back pain (LBP). As part of a standard examination, an experienced clinician assessed passive accessory spinal stiffness of the L3 vertebrae using posterior to anterior (PA) force on the spinous process of L3 in 50 subjects (54% female, mean (SD) age = 33.0 (12.8) years, BMI = 27.0 (6.0) kg/m(2)) with LBP. A criterion measure of spinal stiffness was performed using mechanized indentation by a blinded second examiner. Results indicated that manual assessments were uncorrelated to criterion measures of stiffness (spearman rho = 0.06, p = 0.67). Similarly, sensitivity and specificity estimates of judgments of hypomobility were low (0.20-0.45) and likelihood ratios were generally not statistically significant. Sensitivity and specificity of judgments of hypermobility were not calculated due to limited prevalence. Additional analysis found that BMI explained 32% of the variance in the criterion measure of stiffness, yet failed to improve the relationship between assessments. Additional studies should investigate whether manual assessment of stiffness relates to other clinical and biomechanical constructs, such as symptom reproduction, angular rotation, quality of motion, or end feel.

Anterior talocrural joint laxity: diagnostic accuracy of the anterior drawer test of the ankle.

STUDY DESIGN: Prospective, blinded, diagnostic-accuracy study. OBJECTIVES: To investigate the diagnostic accuracy of the ankle anterior drawer test (ADT) to detect anterior talocrural joint laxity in adults with a history of lateral ankle sprain. BACKGROUND: The ADT is used to manually detect anterior talocrural joint laxity following lateral ankle sprain injury; however, the diagnostic accuracy of this test has not been established. METHODS: Sixty-six subjects with a history of lateral ankle sprain were examined with the ADT. Anterior talocrural joint laxity was measured digitally from ultrasound images of the talofibular interval during performance of the ADT. In addition, anterior talocrural joint laxity was measured digitally in 20 control subjects to establish a reference standard. ADT results were defined as "positive" or "negative," based on this and a second reference standard established from the literature. RESULTS: The group with a history of lateral ankle sprain had a mean ± SD anterior talocrural joint laxity of 3.36 ± 3.25 mm, compared with 0.17 ± 1.87 mm in the control group. Thirty-five of 66 (53%) subjects demonstrated anterior talocrural joint laxity at a reference standard of 2.3 mm or greater, and 24 (36%) at a reference standard of 3.7 mm or greater. Sensitivity of the ADT was 0.74 (95% confidence interval [CI]: 0.58, 0.86) and 0.83 (95% CI: 0.64, 0.93) at the 2.3 mm or greater and 3.7 mm or greater reference standards, respectively. Specificity of the test was 0.38 (95% CI: 0.24, 0.56) and 0.40 (95% CI: 0.27, 0.56), respectively. Positive likelihood ratios were 1.2 and 1.4, whereas the negative likelihood ratios were 0.66 and 0.41, respectively. CONCLUSION: The ADT provides limited ability to detect excessive anterior talocrural joint laxity; however, it may provide useful information when used in side-to-side ankle comparisons and in conjunction with other physical exam procedures, such as palpation. LEVEL OF EVIDENCE: Diagnosis, level 3b.

Talofibular interval changes after acute ankle sprain: a stress ultrasonography study of ankle laxity.

INTRODUCTION: Quantifying talocrural joint laxity after ankle sprain is problematic. Stress ultrasonography (US) can image the lateral talocrural joint and allow the measurement of the talofibular interval, which may suggest injury to the anterior talofibular ligament (ATFL). The acute talofibular interval changes after lateral ankle sprain are unknown. METHODS: Twenty-five participants (9 male, 16 female; age 21.8 ± 3.2 y, height 167.8 ± 34.1 cm, mass 72.7 ± 13.8 kg) with 27 acute, lateral ankle injuries underwent bilateral stress US imaging at baseline (<7 d) and on the affected ankle at 3 wk and 6 wk from injury in 3 ankle conditions: neutral, anterior drawer, and inversion. Talofibular interval (mm) was measured using imaging software and self-reported function (activities of daily living [ADL] and sports) by the Foot and Ankle Ability Measure (FAAM). RESULTS: The talofibular interval increased with anterior-drawer stress in the involved ankle (22.65 ± 3.75 mm; P = .017) over the uninvolved ankle (19.45 ± 2.35 mm; limb × position F1,26 = 4.9, P = .035) at baseline. Inversion stress also resulted in greater interval changes (23.41 ± 2.81 mm) than in the uninvolved ankles (21.13 ± 2.08 mm). A main effect for time was observed for inversion (F2,52 = 4.3, P = .019, 21.93 ± 2.24 mm) but not for anterior drawer (F2,52 = 3.1, P = .055, 21.18 ± 2.34 mm). A significant reduction in the talofibular interval took place between baseline and week 3 inversion measurements only (F1,26 = 5.6, P = .026). FAAM-ADL and sports results increased significantly from baseline to wk 3 (21.9 ± 16.2, P < .0001 and 23.8 ± 16.9, P < .0001) and from wk 3 to wk 6 (2.5 ± 4.4, P = .009 and 10.5 ± 13.2, P = .001). CONCLUSIONS: Stress US methods identified increased talofibular interval changes suggestive of talocrural laxity and ATFL injury using anterior drawer and inversion stress that, despite significant improvements in self-reported function, only marginally improved during the 6 wk after ankle sprain. Stress US provides a safe, repeatable, and quantifiable method of measuring the talofibular interval and may augment manual stress examinations in acute ankle injuries.

Clinimetric analysis of pressure biofeedback and transversus abdominis function in individuals with stabilization classification low back pain.

STUDY DESIGN: Descriptive laboratory study. OBJECTIVE: To determine if a proposed clinical test (pressure biofeedback) could detect changes in transversus abdominis (TrA) muscle thickness during an abdominal drawing-in maneuver. BACKGROUND: Pressure biofeedback may be used to assess abdominal muscle function and TrA activation during an abdominal drawing-in maneuver but has not been validated. METHODS: Forty-nine individuals (18 men, 31 women) with low back pain who met stabilization classification criteria underwent ultrasound imaging to quantify changes in TrA muscle thickness while a pressure transducer was used to measure pelvic and spine position during an abdominal drawing-in maneuver. A paired t test was used to compare differences in TrA activation ratios between groups (able or unable to maintain pressure of 40 ± 5 mmHg). The groups were further dichotomized based on TrA activation ratio (high, greater than 1.5; low, less than 1.5). Sensitivity, specificity, and likelihood ratios were calculated. RESULTS: There was not a significant difference (P = .57) in TrA activation ratios (able to maintain pressure, 1.59 ± 0.28; unable to maintain pressure, 1.54 ± 0.24) between groups. The pressure biofeedback test had low sensitivity of 0.22 (95% confidence interval [CI]: 0.10, 0.42) but moderate specificity of 0.77 (95% CI: 0.58, 0.89), a positive likelihood ratio of 0.94 (95% CI: 0.33, 2.68), and a negative likelihood ratio of 1.02 (95% CI: 0.75, 1.38). CONCLUSION: Successful completion on pressure biofeedback does not indicate high TrA activation. Unsuccessful completion on pressure biofeedback may be more indicative of low TrA activation, but the correlation and likelihood coefficients indicate that the pressure test is likely of minimal value to detect TrA activation. This study was registered with ClinicalTrials.gov (NCT01015846).J Orthop Sports Phys Ther 2013;43(3):184-193. Epub 16 November 2012. doi:10.2519/jospt.2013.4397.

Active ankle motion may result in changes to the talofibular interval in individuals with chronic ankle instability and ankle sprain copers: a preliminary study.

INTRODUCTION: Alterations in talocrural joint arthrokinematics related to repositioning of the talus or fibula following ankle sprain have been reported in radiological and clinical studies. It is unclear if these changes can result from normal active ankle motion. The study objective was to determine if active movement created changes in the sagittal plane talofibular interval in ankles with a history of lateral ankle sprain and instability. METHODS: Three subject groups [control (n = 17), ankle sprain copers (n = 20), and chronic ankle instability (n = 20)] underwent ultrasound imaging of the anterolateral ankle gutter to identify the lateral malleolus and talus over three trials. Between trials, subjects actively plantar and dorsiflexed the ankle three times. The sagittal plane talofibular interval was assessed by measuring the anteroposterior distance (mm) between the lateral malleolus and talus from an ultrasound image. Between group and trial differences were analyzed with repeated measures analysis of variance and post-hoc t-tests. RESULTS: Fifty-seven subjects participated. A significant group-by-trial interaction was observed (F4,108 = 3.5; P = 0.009). The talofibular interval was increased in both copers [2.4±3.6 mm; 95% confidence interval (CI): 0.73-4.1; P = 0.007] and chronic ankle instability (4.1±4.6 mm; 95% CI: 1.9-6.2; P = 0.001) at trial 3 while no changes were observed in control ankle talar position (0.06±2.8mm; 95% CI: -1.5-1.4; P = 0.93). DISCUSSION: The talofibular interval increased only in subjects with a history of lateral ankle sprain with large clinical effect sizes observed. These findings suggest that an alteration in the position of the talus or fibula occurred with non-weight bearing sagittal plane motion. These findings may have diagnostic and therapeutic implications for manual therapists.

The effects of prophylactic ankle bracing on dynamic reach distance and obstacle course performance in military cadets.

Ankle braces can protect the ankle joint from ligament sprains and fractures during high-risk military activities such as physical training and parachuting. Although braces are recommended for injury prevention purposes, the impact of braces on physical performance is unknown. This study evaluated lace-up ankle braces, worn inside the boots, across three conditions: no brace, unilateral brace, and bilateral brace on the dependent variables of dynamic lower extremity reach and obstacle course performance. Thirty-seven military cadets were tested over 3 days. Ankle bracing had a small effect upon anterior and composite lower extremity reach distances. Bracing had no effect upon obstacle course performance times. Inside-the-boot ankle bracing restricts lower extremity reaching and mildly impacts mobility, however, no restrictions were observed with running, climbing, jumping, or negotiating obstacles. Lace-up ankle braces can be used in conjunction with combat boots to protect the ankle during high-risk activities without having an impact upon tactical movements.

Differences in lateral ankle laxity measured via stress ultrasonography in individuals with chronic ankle instability, ankle sprain copers, and healthy individuals.

STUDY DESIGN: Cross-sectional. OBJECTIVE: To use stress ultrasonography to measure the change in anterior talofibular ligament length during the simulated anterior drawer and ankle inversion stress tests. BACKGROUND: In approximately 30% of individuals, ankle sprains may eventually develop into chronic ankle instability (CAI) with recurrent symptoms. Individuals with CAI and those who have a history of ankle sprain (greater than 1 year prior) without chronic instability (copers) may or may not have mechanical laxity. METHODS: Sixty subjects (n=60 ankles) were divided into 3 groups: 1) Control subjects without ankle injury history (n=20; mean ± SD age; 24.8 ± 4.8 years; height, 173.7 ± 9.4 cm; weight, 77.2 ± 19.5 kg), ankle sprain copers (n=20; 22.3 ± 2.9 years; 172.8 ± 11.3 cm; 72.4 ± 14.3 kg), and subjects with CAI (n=20; 23.5 ± 4.2 years; 174.6 ± 9.6 cm; 74.8 ± 17.3 kg). Ligament length change with the anterior drawer and end range ankle inversion was calculated from ultrasound images. The Foot and Ankle Ability Measure (FAAM) was used to quantify self-reported function on activities-of-daily living (ADL) and sports. RESULTS: The anterior drawer test resulted in length changes that were greater (F2,57=6.2, P=.004) in the CAI (mean ± SD length change, 15.6 ± 15.1%, P=.006) and the coper groups (14.0 ± 15.9%, P=.016) compared to the control group (1.3 ± 10.7%); however the length change for the CAI and coper groups were not different (P=.93). Ankle inversion similarly resulted in greater ligament length change (F2,57=6.5, P=.003) in the CAI (25.3 ± 15.5%, P=.003) and coper groups (20.2 ± 19.6%, P=.039) compared to the control group (7.4 ± 12.9%); with no difference in length change between the copers and CAI groups (P=.59). The CAI group had a lower score on the FAAM-ADL (87.4 ± 13.4%) and FAAM-Sports (74.2 ± 17.8%) when compared to the control (98.8 ± 2.9% and 98.9 ± 3.1%, P<.0001) and coper groups (99.4 ± 1.8% and 94.6 ± 8.8%, P<.0001). CONCLUSION: Stress ultrasonography identified greater length changes of the anterior talofibular ligament in both the coper and CAI groups compared to the control group. Only subjects with CAI had reductions in self-reported function.

The effect of traditional bridging or suspension-exercise bridging on lateral abdominal thickness in individuals with low back pain.

CONTEXT: Individuals with low back pain (LBP) are thought to benefit from interventions that improve motor control of the lumbopelvic region. It is unknown if therapeutic exercise can acutely facilitate activation of lateral abdominal musculature. OBJECTIVE: To investigate the ability of 2 types of bridging-exercise progressions to facilitate lateral abdominal muscles during an abdominal drawing-in maneuver (ADIM) in individuals with LBP. DESIGN: Randomized control trial. SETTING: University research laboratory. PARTICIPANTS: 51 adults (mean ± SD age 23.1 ± 6.0 y, height 173.6 ± 10.5 cm, mass 74.7 ± 14.5 kg, and 64.7% female) with LBP. All participants met 3 of 4 criteria for stabilization-classification LBP or at least 6 best-fit criteria for stabilization classification. INTERVENTIONS: Participants were randomly assigned to either traditional-bridge progression or suspension-exercise-bridge progression, each with 4 levels of progressive difficulty. They performed 5 repetitions at each level and were progressed based on specific criteria. MAIN OUTCOME MEASURES: Muscle thickness of the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) was measured during an ADIM using ultrasound imaging preintervention and postintervention. A contraction ratio (contracted thickness:resting thickness) of the EO, IO, and TrA was used to quantify changes in muscle thickness. RESULTS: There was not a significant increase in EO (F1,47 = 0.44, P = .51) or IO (F1,47 = .30, P = .59) contraction ratios after the exercise progression. There was a significant (F1,47 = 4.05, P = .05) group-by-time interaction wherein the traditional-bridge progression (pre = 1.55 ± 0.22; post = 1.65 ± 0.21) resulted in greater (P = .03) TrA contraction ratio after exercise than the suspension-exercise-bridge progression (pre = 1.61 ± 0.31; post = 1.58 ± 0.28). CONCLUSION: A single exercise progression did not acutely improve muscle thickness of the EO and IO. The magnitude of change in TrA muscle thickness after the traditional-bridging progression was less than the minimal detectable change, thus not clinically significant.

Comparison of ankle arthrometry to stress ultrasound imaging in the assessment of ankle laxity in healthy adults.

PURPOSE/BACKGROUND: Ultrasonography (US) may aid the assessment of the anterior talofibular ligament (ATFL) injury after lateral ankle sprains by allowing the clinician to visualize and measure talocrural laxity. Comparison of US against another objective method of ankle laxity assessment, such as ankle arthrometry (AA), is needed. The purpose was to evaluate the relationship between the ATFL length measurements measured from stress US images to the inversion and anterior drawer displacement measured with AA in healthy subjects. METHODS: This descriptive laboratory study included 26 ankles from healthy subjects. The apparent length of the ATFL was measured using US during anterior drawer (USAD) and inversion (USINV) stress and the translation of the talocrural joint was measured using AA during anterior drawer (AAAD) and inversion (AAINV) stress. Percent change in length for USAD and USINV were quantified. Intraclass correlation coefficients and pearson product moment correlations Bland-Altman limits of agreement were calculated between relevant variables. RESULTS: USAD and USINV percent change in length were positively correlated (r = .76). Bland Altman analysis revealed a mean difference of 5.38 mm (95% CI: -3.5 to 12 mm) with the AAAD producing higher values than the USAD. No significant correlations were found between the US and AA variables, however the absolute AAAD and AAINV variables were also positively correlated (r = .61). CONCLUSIONS: The US and AA variables were not directly correlated when measuring inversion and anterior laxity in healthy ankles. Differences between the devices that may affect this include different rates of joint loading, patient position and method of assessing laxity. The AA results demonstrated greater anterior displacement. Results may differ in ankle injured subjects who may demonstrate increases in anteroposterior and inversion laxity. LEVEL OF EVIDENCE: 2b. Exploratory study in healthy cohort.

Metallic foreign body in a patient with knee pain.

The patient was a 26-year-old man with a history of a nonhealing, complicated right clavicle fracture. He also complained of right medial knee pain that was thought to be insidious in onset and made worse during magnetic resonance imaging, which was done to evaluate the status of the right clavicle fracture. Subsequent to the patient reporting his right knee pain to his orthopaedic surgeon, magnetic resonance imaging of the right knee was ordered. Anterior-to-posterior and lateral radiographs were then ordered by the physical therapist, which identified a radioopaque foreign body along the medial knee within the subcutaneous tissues.