RPS 910 - Musculoskeletal ultrasound and ultrasound-guided intervention

Author Block: M. Pansecchi, F. Zaottini, R. Picasso, F. Pistoia, M. Maccio, S. Rinaldi, D. Bianco, G. Marcenaro, C. Martinoli; Genoa/IT
Purpose: Despite advancements in tendon repair techniques, there are still several complications that can occur after tendon surgery. These include adhesion formation, tendon repair rupture, and stiffness of the joints. The aim of this study was to describe the potential role of high-resolution ultrasound (US) to detect postoperative flexor tendon complications after zone-II surgery.
Methods or Background: Twenty-five consecutive patients were submitted to imaging examination for impaired finger flexion/extension after zone-II reconstructive surgery for a previous tear of the flexor digitorum profundus and/or superficialis tendons. Dynamic US examination was performed by means of long- and short axis planes using 18-5 and 22-8MHz linear array probes.
Results or Findings: High-resolution US was able to identify suture material and distinguish stitches of variable thickness and appearance. US imaging over the tendon repair was able to identify focal swelling and prominent knots obstructing tendon gliding. After FT repair, interphalangeal joint contraction and stiffness was found in eight cases without any tendon gliding abnormality. Obstructing gliding and adhesions were observed in twelve cases. In 4/12 cases, adhesions were subtle to recognize and could only be identified on dynamic scans based on traction movements of peritendinous tissues. Tendon repair rupture was observed in n=3 cases as a new tendon discontinuity at the repair site. In one case, bone shortening after P1 fracture and fixation with metallic plate was diagnosed by US. In another case, the FDP tendon was screwed.
Conclusion: Although difficult to perform and operator-dependent, high-resolution US should be regarded as the modality of choice to evaluate the postoperative flexor digitorum tendons in the fingers due to its dynamic capabilities and excellent detail resolution.
Limitations: Further studies based on larger series are needed to define the ultimate value of ultrasound in this field.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was conducted in accordance with the Declaration of Helsinki.

Author Block: L. Lechner, S. A. Jengojan, P. Sorgo, G. Bodner, V. Moser, L. Hirtler; Vienna/AT
Purpose: The objective of this study was to develop and evaluate a minimally-invasive ultrasound-guided thread-release technique for safely and effectively decompressing the first extensor compartment in anatomical specimens.
Methods or Background: De Quervain’s tenosynovitis is a common disabling condition of the hand, arising due to the compression of the tendons in the first extensor compartment. If conservative treatments fail, surgical intervention is required. In recent years, minimally-invasive ultrasound-guided procedures, especially for carpal tunnel syndrome and trigger finger, are on the rise. However, thus far the thread technique was not studied in the release of the first extensor compartment for possible future treatment of De Quervain´s tenosynovitis in an anatomical or clinical setting.
For this study, we developed a protocol for the minimally-invasive ultrasound-guided thread-release and performed it prospectively on ten fresh cadaveric hands. Subsequently, the specimens were dissected and assessed by an experienced anatomist regarding efficacy and safety of the procedure. Ultrasound visibility, degree of transection, and unnecessary damage to surrounding neurovascular structures were documented.
Results or Findings: Ultrasound visibility was sufficient in all specimens. Out of ten interventions, a complete release was achieved in nine cases. Slight, clinically irrelevant, lesions on the underlying extensor tendons were observed in one case. Macroscopically visible neurovascular structures were not harmed in any case.
Conclusion: Real-time ultrasound-guided thread-release is a reliable and safe minimally-invasive method for releasing the first extensor compartment in anatomical specimens while protecting the surrounding structures.
Limitations: This study was conducted on anatomical specimens. Thus, results may differ in the clinical setting. Due to cadaver availability, the initial sample size was limited. Therefore, further anatomical and clinical trials are warranted.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Ethics Committee at the Medical University of Vienna.

Author Block: L. Lechner, L. Hirtler, P. Sorgo, G. Bodner, V. Moser, S. A. Jengojan; Vienna/AT
Purpose: The purpose of this study was to expand the area of application for effective and safe minimally-invasive ultrasound-guided thread-interventions to the transection of the Arcade of Frohse.
Methods or Background: Transection of the Arcade of Frohse becomes clinically relevant in the treatment of radial tunnel syndrome, a rare and painful compressive neuropathy in the proximal forearm. Ultrasound-guided thread-release is a promising new technique for the decompression of peripheral nerves. This study aims to gain initial experience in performing thread-release on the posterior interosseus nerve by transecting the Arcade of Frohse in the anatomical model. Ten ultrasound-guided thread-interventions were performed in fresh cadaveric hands. Subsequent anatomical dissections evaluated outcome of the transection and possible damage to adjacent structures. Ultrasound visibility was also documented for every intervention.
Results or Findings: A complete transection of the Arcade of Frohse was achieved in eight out of ten specimens. Ultrasound visibility was sufficient in all cases. There was no macroscopically visible damage to surrounding neurovascular structures. However, small lesions to the supinator muscle and the superficial extensor muscle were unavoidable in three cases.
Conclusion: Ultrasound-guided thread-transection is a safe and effective minimally-invasive procedure for transecting the Arcade of Frohse in an anatomical model.
Limitations: This study was conducted on fresh anatomical specimens. Therefore, patient results may differ and further cadaveric and clinical studies are warranted. Furthermore, the study sample size is limited due to cadaver availability.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Ethics Committee at the Medical University of Vienna.

Author Block: A. Singh; Amritsar/IN
Purpose: Diabetic peripheral neuropathy (DPN) is a major complication of diabetes mellitus. Clinical examination and nerve conduction study (NCS) of both tibial and median nerves are done to diagnose DPN. The purpose of this study was to perform high-resolution ultrasound with shear wave elastography (SWE) to assess tibial and median nerves mean stiffness as an indicator for development of DPN.
Methods or Background: The study was conducted on 90 subjects which included 30 healthy individuals, 30 diabetic patients without DPN and 30 diabetic patients with DPN. The tibial and median nerve stiffness was measured with SWE. The differences in stiffness values among patients with DPN, patients with clinically defined DPN, patients without DPN, and healthy volunteers based on clinical features and electrodiagnostic tests were evaluated.
Results or Findings: The tibial nerve stiffness based on mean (EMean), minimum (EMin), and maximum
(EMax) shear elasticity indices was significantly higher in patients with DPN and clinically defined DPN than that in patients without DPN and control subjects (p<0.05). EMin cutoff value had a sensitivity, specificity, PLR, and NLR. The inter- and intraobserver agreements
were excellent for the SWE measurements.
Conclusion: Tibial nerve stiffness is significantly higher in diabetic patients with DPN and clinically defined DPN. The EMean and EMin have a good accuracy for identifying DPN. SWE has a potential use for cases with clinically defined DPN.
Limitations: The study was limited by its small sample size.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Institutional Ethical and Research Committee.

Author Block: J. Kim, Y. Kim, C-H. Lee, S. Lee; Seoul/KR
Purpose: The objective of this study was to evaluate the imaging characteristics of hourglass constriction (HC) of the radial nerve using ultrasonography (USG) and MRI correlating with surgical observations.
Methods or Background: From March 2020 to September 2023, the preoperative USG and MRI of six patients (5 men, 1 woman; mean age 30.5 years old) who were surgically confirmed were retrospectively evaluated. The location and number of HCs identified by both USG and/or MRI, as well as the signal intensity of the nerve in axial fat-suppressed T2 weighted images (FST2), were assessed and compared with surgical observations.
Results or Findings: A total of 37 HCs were identified across the six patients. All patients exhibited three or more multiple HCs. The most common locations for HCs were the intermuscular space between the brachialis and brachioradialis muscles (19/37, 51.4%), followed by the lateral epicondyle level (7/37, 18.9%) and the arcade of Frohse (4/37, 10.8%). On FST2, the peripheral high signal intensity and central low signal intensity (referred to as the "bull's eye sign") was most frequently observed proximal to the HC (20/37, 54.1%). Out of the 37 HC sites, 23 were found to have constriction bands around the perineurium of the fascicle of the deep radial nerve. This was most often located near the branching site from the radial nerve within the intermuscular space between the brachioradialis and brachialis muscles.
Conclusion: Hourglass constrictions of the radial nerve typically show multiple involvements in the perineurium of the deep radial nerve fascicle with bull’s eye sign, especially around the branching site from the radial nerve between the brachialis and brachioradialis muscles.
Limitations: This study was a retrospective study of a single centre, with a small sample size and a lack of consensus in the accurate cutoff degree of significant hourglass constriction.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Hanyang University Research Committee.

Author Block: F. Pistoia, F. Zaottini, R. Picasso, M. Maccio, D. Bianco, S. Rinaldi, M. Pansecchi, C. Martinoli; Genoa/IT
Purpose: The purpose of this study was to determine the ability of high-frequency ultrasound (HRUS) to assess the pulleys of the flexor tendons of the toes.
Methods or Background: The initial phase of the study involved examining the pulley system of flexor tendons of the toes in six cadaveric specimens using high-frequency ultrasonography. Coloured latex was then injected under US guidance at various pulley levels. In the subsequent part of the research, a 22-8 MHz US probe was used to evaluate the toe pulley system in 40 feet of 20 healthy volunteers. Then, five patients with hammer toes were evaluated using the same US probe.
Results or Findings: The coloured latex was placed correctly in all six specimens. The toe pulleys were consistently identified with HRUS on all forty healthy volunteers. All five patients demonstrated a mean thickness value of the AIII pulley of the affected toes superior to the respective toes in the healthy group.
Conclusion: High-frequency US allows excellent depiction of toe pulleys. However, further research is necessary to understand the potential impact of thickened pulleys on hammer toe deformity.
Limitations: This is a first explorative study. Further research in larger population is needed to understand the clinical value of this ultrasound application.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was performed in line with the principles of the Declaration of Helsinki.

Author Block: F. Serpi¹, U. Viglino², C. Messina¹, S. Fusco¹, S. Gitto¹, F. Lacelli³, L. M. Sconfienza¹, D. Albano¹; ¹Milan/IT, ²Genoa/IT, ³Pietra Ligure/IT
Purpose: This study aimed to investigate the efficacy and safety of ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT) applied out of the shoulder, comparing its effectiveness to US-PICT of the rotator cuff.
Methods or Background: Patients subjected to US-PICT for extra-shoulder calcific tendinitis (Case Group) were compared to those subjected to US-PICT of the rotator cuff (Control Group). We had pre-procedure VAS (visual analogue scale) pain score, 1-month and 3-month VAS of patients of the Case Group, pre-procedure, and 3-month VAS of patients of the Control Group.
Results or Findings: The Case Group consisted of 41 patients (27 women; mean age: 45±9years): 26 gluteus medius, 5 patellar tendon, 3 rectus femoris, 2 gluteus maximus, 2 common extensor tendon, 1 extensor carpi radialis longus, 1 pes anserinus, 1 peroneus longus. The Control Group included 41 patients (27 women; mean age: 47±11 years). The mean pre-procedure VAS of the Case Group was 8.8±0.7 with a significant (P<0.001) drop at 1 month (4.5±0.6) and 3 months (3.6±0.6). The mean pre-procedure VAS of the Control Group was 8±1.4 and dropped to 3.1±1.6 after 3 months (P<0.001). Post-treatment VAS at 3 months was not significantly different between two Groups (p=0.134). Similarly, the decrease of VAS from baseline to three months was not significantly different between the two Groups (p=0.264).
Conclusion: This study demonstrated the safety and effectiveness of US-PICT as a valuable therapeutic option for extra-shoulder calcific tendinitis, with similar clinical outcome to the same procedure performed in the rotator cuff.
Limitations: This study had a relatively small sample size with few cases in some localisations. A further limitation is the retrospective nature of the study, warranting prospective studies to compare the procedure with other conservative approaches and to understand how to manage these patients postoperatively.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: No information provided by the submitter.

Author Block: U. Viglino¹, F. Esposito², D. Albano³, S. Gitto³, C. Messina³, L. M. Sconfienza³; ¹Genoa/IT, ²Napoli/IT, ³Milan/IT
Purpose: Shear wave elastography is a renowned ultrasound technique that quantitatively evaluates the elasticity of tissues. The aim of this study is to validate the reproducibility of elasticity measurements of the Achilles and patellar tendons in healthy subjects using ultrasound machines from three different manufacturers and to compare intraobserver and interobserver variations between two examiners.
Methods or Background: High-resolution linear probes were used on three ultrasound machines from different manufacturers. The study included 13 healthy volunteers with no prior history of tendon injuries. Data acquisition was performed in both supine and prone rest positions, with three measurements taken for each tendon on each side of the body, for a total of 26 tendons. Each joint was repositioned after the measurement. A comparison of intraobserver variations was made with a reevaluation after two weeks (T1).
Results or Findings: Intraobserver reproducibility of the three different acquisitions on each tendon was demonstrated for both observers on the three ultrasound machines (p<0.001). Intraobserver reproducibility T0-T1 was statistically significant (p<0.05) for only one observer across the three ultrasound machines for both tendons. Interobserver reproducibility was statistically significant (p<0.05) only for patellar tendon on two of the ultrasound machines [0.398 (CI 0.02-0.676); 0.421 (CI 0.048-0.691)]. Intervendor reproducibility was poor, not statistically significant [Reader 1 0.257 (CI -0.138-0.581) for patellar and 0.222 (CI -0.174-0.556) for Achilles] [Reader 2 0.075 (CI -0.315-0.443 for patellar and -0.118 (CI -0.477-0.275) for Achilles].
Conclusion: This study demonstrated that shear wave ultrasound could be a useful quantitative tool for the study of tendons but its reproducibility is acceptable only in specific conditions (such as with the same sonographer). Reproducibility has shown to be suboptimal in other applications, for example in reexamination, with a different sonographer, and poor with different ultrasound machines.
Limitations: This study was limited by the lack of supersonic shear imaging (SSI).
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: No information provided by the submitter.

Author Block: M. K. J. Mahazer; Terengganu/MY
Purpose: The purpose of this study is to determine the potential of shear wave elastography (SWE) in measuring the median stiffness value of enthesis in healthy subjects and to assess interobserver reliability.
Methods or Background: Ninety-eight healthy male and female subjects aged 20-50 years underwent SWE of the bilateral enthesis of quadriceps, suprapatellar, infrapatellar, Achilles, and triceps performed by two experienced sonographers. Each enthesis was evaluated five consecutive times using the ElastQ software. Median shear wave velocity values were compared for each enthesis by each examiner. Interobserver agreement was evaluated.
Results or Findings: Kruskal Wallis and ANOVA tests showed significant differences in median shear wave velocity (SWV) of enthesis for quadriceps, suprapatellar, and left Achilles between the 40-50 age group vs the 20-29 age group and the 30-39 vs 40-49 age groups. However, insignificant difference of median SWV was found in the infrapatellar and right Achilles. The median (IQR) stiffness of quadriceps for age groups 20-39 and 40-50 were 2.96m/s (0.42) and 2.80m/s (0.36), suprapatellar for age groups 20-39 were 3.00m/s (0.27), and for ages 40-50 were 2.90m/s (0.32), and left Achilles 20-39 years old 33.12 m/s (0.55) and 40-50 years old (2.91m/s (0.29) respectively. Good interobserver agreement was found between quadriceps, suprapatellar, infrapatellar, and Achilles (95% CI; 0.84) (p<0.01).
Conclusion: The study suggests that shear wave elastography holds potential as a reliable technique for quantifying enthesis stiffness. It is noteworthy that age does not appear to have a significant influence on the median shear wave velocity (SWV) of entheses, except for the quadriceps, suprapatellar, and left Achilles in patients aged 40-50.
Limitations: The study was limited by its small sample size, and the lack of additional imaging such as MRI.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the University of Malaya Medical Centre, MREC ID NO: 2021112-10731.

Author Block: G. Marcenaro; Genoa/IT
Purpose: The anterior talofibular ligament (ATFL) is usually considered as a single fascicle but it is actually made of two different bands, the superior and the inferior bands. The main objective of this study is to determine the role that these two fascicles play in the ankle stability.
Methods or Background: We recruited 86 patients who accessed the emergency department for ankle sprain. An x-ray exam has been used to rule out patients with fractures. After 14 days patients underwent an ultrasound examination to look for injuries of the superior and inferior fascicle of the ATFL. Each fascicle has been given a score (0 to 3) to describe the severity of the injury. An objective measure of the articular instability has been made measuring the minimum (a) and maximum (b) distance between the tip of the fibula and the body of the talus, positioning the foot in plantar flexion and inversion (a) and in dorsiflexion and eversion (b). Two months after the exam, patients were asked to fill in the CAIT questionnaire to provide objective data about ankle instability, which was correlated with the findings of the ultrasound exam.
Results or Findings: In a population of 86 patients, the multivariate analysis shows that there is a significant relation between injury of the calcaneofibular ligament CFL and ankle instability (p≤0.029) and between the two fascicles of the ATFL an injury of the superior is more likely to cause instability.
Conclusion: The CFL is the most important ligament for preserving ankle stability. There is a trend showing that the superior band of the ATFL is more responsible for ankle stability than the inferior, which is to be confirmed with a broader dataset.
Limitations: Recruitment for a follow-up study is in progress, as this study is based on the questionnaire responses of 100 patients.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study has been approved by the ethics committee of San Martino Hospital HRCCS of Genoa, Italy.