Ultrasonographic measurement of the cross-sectional area of the axillary nerve.

INTRODUCTION: The objectives of this study were to determine normal reference values for ultrasonographic measurement of the cross-sectional area (CSA) of the axillary nerve and to standardize the measurement methods. METHODS: Sixty healthy volunteers were evaluated. Ultrasonography was performed with the shoulder positioned in 100°-120° abduction and 90° external rotation. The CSA of the axillary nerve was measured bilaterally. RESULTS: The normal CSA of the right axillary nerve was 2.9 ± 1.1 mm2 . The side-to-side discrepancy was 22.8% ± 17.8%. DISCUSSION: These reference values may be helpful for investigating pathologies involving the axillary nerve.

Use of 18F-sodium fluoride bone PET for disability evaluation in ankle trauma: a pilot study.

BACKGROUND: There are no objective and accurate rating tools for permanent impairment of traumatized ankles. The purpose of this study is to assess the role of 18F-Sodium fluoride (18F-NaF) positron emission tomography-computed tomography (PET/CT) bone scans in evaluating patients with limited ankle range of motion (ROM) after trauma. METHODS: 18F-NaF PET/CT was performed in 121 patients (75 men, 46 women; mean age: 45.8) who had ROM < 70% of normal after trauma affecting ankles. Metabolic target volume (MTV), the sum of voxels with standardized uptake value (SUV) > 2.5 was automatically obtained from the 3D volume that included the ankle joint. The maximum & mean SUV (SUVmax & SUVmean), and the total lesion activity (TLA) were measured. RESULTS: The median period from injury to performing 18F-NaF PET/CT was 290 days. The causes of injury were as follows: fracture (N = 95), Achilles tendon rupture (N = 12), and ligament injury (N = 12). Hot uptake in the ankle was seen in 113 of 121 patients. The fracture group had higher SUVmax, SUVmean, and TLA values than the non-fracture group. More limited ROM correlated with higher hot-uptake parameters (SUVmax, SUVmean, TLA). In subgroup analysis, the same correlations were present in the fracture, but not in the non-fracture group. CONCLUSIONS: 18F-NaF PET/CT can provide considerable information in impairment evaluations of limited ankle ROM, particularly in fracture around the ankle. Thus, 18F-NaF bone PET/CT may provide an additional option as an objective imaging tool in disability assessment after ankle injury.

Team's average acute:chronic workload ratio correlates with injury risk in NCAA men's soccer team.

BACKGROUND: Research in multiple sports has shown that an individual's acute:chronic workload ratio (ACWR) correlates with injury. However, tailoring team trainings to each individual's ACWR is technically challenging and has not been found to decrease injury risk. OBJECTIVE: To establish a more feasible method of utilizing the ACWR for injury prevention in soccer. In a National Collegiate Athletic Association (NCAA) men's soccer team, we assessed whether the team's average ACWR, as opposed to that of each individual, correlated with injuries sustained throughout the season. DESIGN: Injury and workload data were retrospectively evaluated for all players (n = 23) of an NCAA men's soccer team during one 18-week season. Workload data for five global positioning system (GPS)-derived workload variables (total distance, high-speed distance, accelerations, player load, and average velocity) were used to calculate the team's average daily acute and chronic workloads (accumulated load for each variable during the past 3 and 28 days, respectively), and uncoupled ACWRs (acute workload divided by chronic workload for each variable). A retrospective cohort design was used to compare the team's workloads and ACWRs on days where ≥1 injury occurred versus days where zero injuries occurred using binary logistic regression models. RESULTS: Trainings/games with injuries had higher acute workloads, lower chronic workloads, and higher ACWRs for all five workload variables. In multivariable analysis, risk factors for injury included a low chronic workload for total distance (odds ratio [OR] 7.23, p = .024) and an ACWR >1.4 for accelerations (OR 4.34, p = .029). CONCLUSIONS: The team's injury risk was greater with low distance accumulation during the chronic period and with an elevated ACWR for accelerations. Future intervention-based studies aimed at using ACWR load-management principles as a method of decreasing injury risk in soccer can consider tracking the team's average values with the goal of maintaining a consistent chronic workload for total distance and avoiding elevations in the ACWR for accelerations.

Orthobiologics for the Hip Region: A Narrative Review.

Management of hip region disorders is challenging. Orthobiologic treatments including platelet rich plasma (PRP), mesenchymal stem cells, and amniotic injectables have gained popularity as promising treatments despite a lack of robust evidence for their effectiveness. We review rationale and current evidence for orthobiologics for three common hip region conditions: hip osteoarthritis, gluteal tendinopathy, and proximal hamstring tendinopathy. Overall, the current state of evidence is extremely limited for orthobiologic treatments and is predominantly relevant to PRP injections. There is currently a lack of data to support the use of mesenchymal stem cells or amniotic injectables in these conditions of the hip.

Golf Swing Rotational Velocity: The Essential Follow-Through.

OBJECTIVE: To evaluate if shoulder and pelvic angular velocities differ at impact or peak magnitude between professional and amateur golfers. Golf swing rotational biomechanics are a key determinant of power generation, driving distance, and injury prevention. We hypothesize that shoulder and pelvic angular velocities would be highly consistent in professionals. METHODS: Rotational velocities of the upper-torso and pelvis throughout the golf swing and in relation to phases of the golf swing were examined in 11 professionals and compared to 5 amateurs using three-dimensional motion analysis. RESULTS: Peak rotational velocities of professionals were highly consistent, demonstrating low variability (coefficient of variation [COV]), particularly upper-torso rotational velocity (COV=0.086) and pelvic rotational velocity (COV=0.079) during down swing. Peak upper-torso rotational velocity and peak X-prime, the relative rotational velocity of uppertorso versus pelvis, occurred after impact in follow-through, were reduced in amateurs compared to professionals (p=0.005 and p=0.005, respectively) and differentiated professionals from most (4/5) amateurs. In contrast, peak pelvic rotational velocity occurred in down swing. Pelvic velocity at impact was reduced in amateurs compared to professionals (p=0.019) and differentiated professionals from most (4/5) amateurs. CONCLUSION: Golf swing rotational velocity of professionals was consistent in pattern and magnitude, offering benchmarks for amateurs. Understanding golf swing rotational biomechanics can guide swing modifications to help optimize performance and prevent injury.

Comparison of Muscle Onset Activation Sequences between a Golf or Tennis Swing and Common Training Exercises Using Surface Electromyography: A Pilot Study.

Aim. The purpose of this pilot study is to use surface electromyography to determine an individual athlete's typical muscle onset activation sequence when performing a golf or tennis forward swing and to use the method to assess to what degree the sequence is reproduced with common conditioning exercises and a machine designed for this purpose. Methods. Data for 18 healthy male subjects were collected for 15 muscles of the trunk and lower extremities. Data were filtered and processed to determine the average onset of muscle activation for each motion. A Spearman correlation estimated congruence of activation order between the swing and each exercise. Correlations of each group were pooled with 95% confidence intervals using a random effects meta-analytic strategy. Results. The averaged sequences differed among each athlete tested, but pooled correlations demonstrated a positive association between each exercise and the participants' natural muscle onset activation sequence. Conclusion. The selected training exercises and Turning Point™ device all partially reproduced our athletes' averaged muscle onset activation sequences for both sports. The results support consideration of a larger, adequately powered study using this method to quantify to what degree each of the selected exercises is appropriate for use in both golf and tennis.

Basic appearance of ultrasound structures and pitfalls.

The role of ultrasound in musculoskeletal imaging is expanding as technology advances and clinicians become better educated about its clinical applications. The main use of musculoskeletal ultrasound to physiatrists is to examine the soft tissues of the body and to diagnose pathologic changes. Ultrasound can be used to assist clinicians in performing interventional procedures. However, to successfully integrate this technology into their clinical practices, physicians must be familiar with the normal and abnormal appearance of tissues. They also must recognize the clinically relevant limitations and pitfalls associated with the use of ultrasound.