Application Value of Musculoskeletal Ultrasound in DAA-THA with Conjoined Tendon Repair

Objective:To observe the ultrasonographic characteristics of conjoined tendon repair in direct anterior approach for total hip arthroplasty(DAA-THA),and to evaluate the efficacy of musculoskeletal ultrasound in determining the healing after joint tendon repair.Methods:A total of 60 patients who required primary total hip arthroplasty in Yulin Orthopedic Hospital of Chinese and Western Medicine from July 2020 to July 2021 were selected;the patients were divided into two groups,an observation group,group A(n=30),and a control group,group B(n=30),according to different intraoperative methods.There was no significant difference in gender,age,and diagnosis between the two groups.Direct anterior approach was used for both the groups.For group A,the joint capsule and conjoined tendon(superior gemellus,obturator internus,and inferior gemellus)were repaired in situ,whereas for group B,only the joint capsule was repaired in situ,while the conjoined tendon was not repaired.The healing of the tendon was observed.Results:(1)in terms of diagnosis,after conjoined tendon repair,26 cases in group A showed good tendon continuity,good tension,and a small amount of effusion echo around,three cases showed partial interruption of tendon echo,low echo,or no echo inside with insufficient structural clarity,and a case showed complete interruption;in group B,all 30 cases had continuous interruption,poor tension,tendon retraction,and thickening;the healing rate of group A’s conjoined tendon repair was 96.67%;(2)in terms of prognostic assessment,one month after the surgery,the Harris score of group A was significantly higher than that of group B(P<0.05);however,there was no significant difference in the terms of the Harris score between the two groups 3-6 months after surgery(P>0.05);the effective tension of conjoined tendon and the effective muscle strength of group A were significantly higher than those of group B(P<0.05).Conclusion:Musculoskeletal ultrasound has high diagnostic value in the healing of conjoined tendon and provides dynamic clinical observation after conjoined tendon repair in DAA-THA;it is proven that DAA-THA with conjoined tendon repair on the premise of reconstructing the joint capsule can well restore its tension,enhance its muscle strength,significantly improve early joint stability and joint function,as well as facilitate the rapid recovery of patients.

Relationships between the sound speed ratio and physical properties of surface sediments in the South Yellow Sea

Building empirical equations is an effective way to link the acoustic and physical properties of sediments.These equations play an important role in the prediction of sediments sound speeds required in underwater acoustics.Although many empirical equations coupling acoustic and physical properties have been developed over the past few decades,further confirmation of their applicability by obtaining large amounts of data,especially for equations based on in situ acoustic measurement techniques,is required.A sediment acoustic survey in the South Yellow Sea from 2009 to 2010 revealed statistical relationships between the in situ sound speed and sediment physical properties.To improve the comparability of these relationships with existing empirical equations,the present study calculated the ratio of the in situ sediment sound speed to the bottom seawater sound speed,and established the relationships between the sound speed ratio and the mean grain size,density and porosity of the sediment.The sound speed of seawater at in situ measurement stations was calculated using a perennially averaged seawater sound speed map by an interpolation method.Moreover,empirical relations between the index of impedance and the sound speed and the physical properties were established.The results confirmed that the existing empirical equations between the in situ sound speed ratio and the density and porosity have general suitability for application.This study also considered that a multiple-parameter equation coupling the sound speed ratio to both the porosity and the mean grain size may be more useful for predicting the sound speed than an equation coupling the sound speed ratio to the mean grain size.