Measuring stiffness of normal medial collateral ligament in healthy volunteers via shear wave elastography

Regional assessments of supraspinatus muscle stiffness in normal adults using shear wave elastography

Objectives

To provide normal references for regional shear wave elastography assessments of supraspinatus muscle in a population.

Methods

Shear wave elastography images of supraspinatus muscles were evaluated on 100 shoulders of 50 normal adults in a fixed position with 30° shoulder abduction both at rest and contraction. Shear wave velocity values and activity values of intramuscular tendon, anterior superficial, anterior deep, posterior superficial, posterior deep, and central subregions were measured. The possible differences in hand dominance, sexes, stratified age groups, and internal muscular-component subregions were discussed.

Results

The results showed that shear wave velocity values at rest and activity values differed significantly among supraspinatus muscular-component subregions. Shear wave velocity values at rest were normally highest in posterior deep and lowest in central subregions, whereas activity values were highest in central subregions. The results also showed evaluation of the intramuscular tendon using shear wave elastography to be practicable. The differences in shear wave velocity values at rest between the dominant and nondominant sides were not significant in each subregion, while the values at rest of the majority of subregions were significantly greater in males than in females. Stratified by age groups of 10 years, the shear wave velocity values at rest of some subregions tended to increase with age, with uncorrelations possibly related to insufficient sample sizes and different intensities of limb activities.

Conclusions

This study suggested that regional assessments of supraspinatus stiffness using shear wave elastography are feasible, with further research supporting that it can provide information on the surgery, training, and rehabilitation of rotator cuff tears.

A Preliminary Study to Assess the Relevance of Shear-Wave Elastography in Characterizing Biomechanical Changes in the Deltoid Ligament Complex in Relation to Ankle Position

BACKGROUND

The purpose of this study was (1) to evaluate the biomechanical properties of the different bundles of the deltoid ligament in various ankle positions in a cohort of healthy adult volunteers; (2) describe the impact of demographic and hindfoot morphology characteristics on their stiffness; (3) to assess the reliability and reproducibility of these measurements.

METHODS

Deltoid ligament complex of both ankles were assessed by shear-wave elastography (SWE) in 20 healthy patients resting on hinge support. The propagation shear-wave speed (SWS) in ligaments was measured, which is related to the tissue's elastic modulus. The following ligaments were analyzed in a neutral position and then in varus, valgus, dorsal, and plantar flexions: tibionavicular ligament (TNL), tibiocalcaneal ligament (TCL), the superficial posterior tibiotalar ligament (SPTL), the anterior tibiotalar ligament (ATTL), and the deep posterior tibiotalar ligament (DPTTL).

RESULTS

The mean SWS increased between neutral and 20 degrees valgus position for TCL (4.08 ± 0.78 m/s vs 5.56 ± 0.62 m/s, respectively; P < .0001) and for DPTTL (2.58 ± 0.52 m/s vs 3.59 ± 0.87 m/s, respectively; P < .0001). The mean SWS increased between neutral and 30 degrees plantarflexion for ATTL (2.11 ± 0.44 m/s vs 3.1 ± 0.5 m/s, respectively; P < .0001) and TNL (2.96 ± 0.66 m/s vs 4.99 ± 0.69 m/s, respectively; P < .0001). The mean SWS increased between neutral and 20 degrees dorsal flexion for SPTL (4.2 ± 1 m/s vs 5.45 ± 0.65 m/s, respectively; P < .0001).Women had less DPTTL SWS than men in the neutral position (2.37 ± 0.35 m/s vs 2.71 ± 0.49 m/s, respectively; P = .007). Other demographics had no impact on the SWS value of other ligaments. All inter- and intraobserver agreements were good to excellent.

CONCLUSION

This study presents a reliable and reproducible SWE measurement protocol to describe the physiological function of all bundles of the medial collateral ligament in healthy adults.

CLINICAL RELEVANCE

This examination technique can be available to orthopaedic surgeons, allowing reliable and reproducible monitoring of the SWS of the various ligaments constituting the medial collateral plane. The biomechanical values described in this study may give insight into in what position medial ankle ligament reconstruction should be tensioned.

Do deep inspiration breath-holds and free-breathing affect pancreatic tissue stiffness in shear wave elastography?

PURPOSE

The use of ultrasound (US) elastography to assess the pancreas is subject to serious limitations, and it is not easy to perform US elastography for the pancreas with satisfactory and reproducible accuracy. The aim of our study was to show the normal pancreatic stiffness values with shear wave elastography (SWE) and to evaluate the pancreatic tissue stiffness at two different respiratory phases.

METHODS

Sixty-three subjects were included in the study. Median values of pancreatic stiffness were recorded. Values during deep inspiration and free breathing were compared.

RESULTS

The stiffness values of the pancreatic tissue measured during deep inspiration breath holds and during free breathing were 5.70 ± 1.74 kPa and 4.15 ± 1.70 kPa, respectively. It was found that the values of pancreatic tissue stiffness measured during deep inspiration were statistically significantly higher than those measured during physiological breathing (p < 0.001).

CONCLUSIONS

Because of the reference value differences between different ultrasound elastography devices, it is important to know the reference ranges of normal pancreatic stiffness according to the device, in order to distinguish possible pathologies. In addition, the variability of pancreatic stiffness measurements with respiratory phases should be considered in clinical applications.

The effect of tourniquet application on the morphology and function of quadriceps in patients undergoing total knee arthroplasty: study protocol for a single-blind randomized controlled trial

Background

Tourniquet is currently widely used in total knee arthroplasty to reduce intraoperative blood loss. The academic view of tourniquet application in TKA is now in dispute. Some scholars argue that tourniquet may cause quadriceps injury and bring extra side effects, so they oppose the application of tourniquet. Others find that tourniquet application has no significant adverse impact on TKA patients. Regarding its advantages in reducing intraoperative blood loss, they advocate the regular application of tourniquet in TKA. Quadriceps injury is considered the main cause of tourniquet side effects. There are now many high-quality trials about tourniquet application in TKA but few of them concentrate on quadriceps morphology and function.

Methods

A prospective, single-blind, randomized controlled trial will be adopted. The target sample is 130. Patients who meet the eligibility criteria will be randomly allocated to the tourniquet group and non-tourniquet group. The primary outcome is quadriceps thickness evaluated by ultrasound test. Secondary outcomes include quadriceps stiffness, rehabilitation outcomes, operation time, intraoperative and postoperative blood loss, blood transfusion rate, thigh circumference, VAS score, opioid consumption, d-dimer and C-reactive protein level in the serum, knee function score, postoperative satisfaction score, and complications.

Discussion

This proposed study will contribute to improve evidence of tourniquet application in total knee arthroplasty. This will be a high-quality single-blind randomized controlled trial with a sufficient sample size and strict study design. It will investigate the effects of tourniquet application especially on the morphology and function of quadriceps in patients undergoing total knee arthroplasty and offer advice for tourniquet application in clinical practice.

Trial registration

Chinese Clinical Trial Registry ChiCTR2000035097. Registered on 31 July 2020