Ultrasound-guided thermal radiofrequency ablation of the genicular nerves after total knee replacement.

The rate of refractory chronic pain after total knee replacement (TKR) is 20-25%, with no identifiable etiology in 6% of cases. Without an etiologic diagnosis, the surgeon is unlikely to consider revision, but pain poses a therapeutic challenge for achieving satisfaction and an acceptable quality of life. Genicular nerve radiofrequency ablation (GNRFA) was recently developed as a non-drug analgesic option. It is minimally invasive and safe, with few adverse effects, opening a new perspective for management of refractory chronic pain after TKR. LEVEL OF EVIDENCE: IV.

Paget's Disease or Densifying Metastasis: How to Sort It Out.

Although the prevalence of Paget's disease has decreased over the past 20 years, incidental discovery on imaging is not unusual. The challenge is to establish the diagnosis, especially in unusual forms that may be mistaken for metastases. This review describes the typical imaging features of Paget's disease and some rare presentations that may be more difficult to recognize.

Revisiting idiopathic eosinophilic myositis: towards a clinical-pathological continuum from the muscle to the fascia and skin.

OBJECTIVES: Idiopathic inflammatory myopathies are mainly defined by inflammatory infiltrates within the muscle (lymphocytes and macrophages). Eosinophil muscle infiltration has been described in idiopathic eosinophilic myositis (IEM) and rarely in EF. This study aimed to further delineate the nosological frame of idiopathic eosinophil muscle infiltration through the exhaustive analysis of IEM and EF patients. METHODS: This multicentre retrospective case series included IEM patients diagnosed between 2000 and 2022. IEM inclusion criteria were eosinophilic muscle infiltration with myositis pathological features, after the exclusion of differential diagnoses. An additional group of EF patients diagnosed between 2016 and 2022 was constituted. Inclusion criteria were an EF diagnosis and fascia thickening with inflammatory infiltrate. RESULTS: A total of 20 IEM cases and 10 EF cases were included. The median (interquartile range) age at diagnosis was 65 (49-70) years; there were 18 males. Data analysis delineated four subgroups: focal EM (FEM, n = 3), diffuse EM (DEM, n = 6), eosinophilic myofasciitis (EMF, n = 11) and EF (n = 10). FEM represented a limited and benign form of myositis. DEM cases presented objective muscle impairment with eosinophilic muscle infiltration. EMF patients presented subjective muscle impairment (myalgia, 55%), fasciitis (on histology and/or imaging), eosinophilic muscle infiltration and frequent hypereosinophilia (55%). EF patients presented myalgia (50%), muscle lesions on histology with fascia-restricted inflammatory infiltrates with (60%) or without (40%) eosinophils. CONCLUSIONS: The analysis of IEM and EF patient characteristics delineates four subgroups (FEM, DEM, EMF and EF) in terms of clinical, laboratory, imaging, pathological and outcome specificities, and proposes an adapted diagnostic and care management approach.

Ultrasonography: an interesting imaging method for ligament assessment during the acute phase of closed elbow injuries.

PURPOSE: To evaluate whether ultrasonography can be used to explore the medial and lateral ligament structures during the acute phase of a closed elbow injury. METHODS: A single-center, prospective study performed between December 2019 and June 2020, including patients who suffered a radial head fracture or elbow dislocation. Two radiologists did a blinded analysis using ultrasonography of visibility, injury grade, and presence of bone avulsion for the radial collateral ligament (RCL), lateral ulnar collateral ligament (LUCL), annular ligament (AL), and anterior (MCLant) and posterior bundles (MCLpost) of the medial collateral ligament. The inter-rater agreement was calculated. The ultrasonography findings were compared with the intraoperative findings in the patients who subsequently underwent surgery. RESULTS: Forty patients were included (28 radial head fractures and 12 elbow dislocations). The inter-rater agreement was strong for all the study parameters (kappa between 0.65 and 1), except for the visibility of the LUCL (kappa 0.52) and the visibility and appearance of the MCLpost (kappa 0.54 and 0.47, respectively). The injured ligaments were thicker than their contralateral counterparts (p < 0.05). In the 10 patients who underwent surgery, the radiological-surgical correlation was 100% for the RCL and medial ligaments and 70% for the LUCL. CONCLUSION: Ultrasonography is a reproducible examination that can be used to assess the damage to elbow ligaments during the acute phase following an injury. This examination could be incorporated into the exploration protocol for elbow injuries during the preoperative assessment and to adapt the treatment.

Prevalence and Detection of Meniscal Ramp Lesions in Pediatric Anterior Cruciate Ligament-Deficient Knees.

BACKGROUND: Anterior cruciate ligament (ACL) tears represent 13% of knee injuries in children. Medial meniscal tears are commonly associated with ACL ruptures. Ramp lesions correspond to posterior meniscocapsular tears of the medial meniscus. Depending on the study, the prevalence of ramp lesions is inconsistent. PURPOSE: To describe the prevalence of ramp lesions in children and adolescents and to investigate the sensitivity of magnetic resonance imaging (MRI) for diagnosing such lesions. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 3. METHODS: We analyzed videos from arthroscopic ACL reconstruction (ACLR) in children. During these procedures, we systematically looked for potential ramp lesions. To do so, an arthroscope was passed through the intercondylar notch to visualize the posteromedial compartment. A needle was introduced at the site of a posteromedial portal to unfold the meniscocapsular junction to reveal any hidden meniscal tear. Surgical procedures were performed by 2 senior surgeons. Videos were blindly analyzed by a third surgeon. Preoperative MRIs were screened by 2 blinded, independent senior radiologists to look specifically for ramp lesions. RESULTS: Videos of 50 consecutive arthroscopic ACLRs concerning 32 boys and 18 girls were analyzed. Mean age at surgery was 14.2 years (range, 8.5-17.6 years). A total of 14 ramp lesions (28%) in 8 boys and 6 girls were identified. In addition, there were 22 tears of the meniscal body in 20 patients (40%). Arthroscopic and MRI findings did not correlate. Among 14 arthroscopically diagnosed ramp lesions, only 8 were detected on the MRI. Conversely, 12 patients had a ramp lesion detected on the MRI, which could not be confirmed intraoperatively. The sensitivity of MRI was 57% and the positive predictive value was 40%. CONCLUSION: A meniscal ramp lesion was present in 14 of 50 children (28%) undergoing ACLR. MRI has a low sensitivity for diagnosis of ramp lesions in children. Careful exploration of the posteromedial compartment is strongly recommended. Overlooking such lesions during ACLR may contribute to ongoing instability and higher re-rupture rates in these young patients.

Bifascicular nature of the flexor digitorum profundus and flexor pollicis longus tendons: forgotten anatomical characteristics rediscovered with US imaging.

OBJECTIVES: To demonstrate the bifid configuration of the flexor digitorum profundus (FDP) and flexor pollicis longus (FPL). METHODS: In the first part of this study, 20 digits from 4 cadaver hands were dissected and analyzed using anatomical and histological slices. The second part of the study was carried out over a 12-month period starting in August 2018. It was a prospective US imaging study of 300 digits from 30 healthy participants performed by two radiologists in a double-blinded manner. This study focused on two items: tendon shape and whether a central septum separated the two hemitendons. Descriptive statistics were calculated along with the inter-rater reliability. RESULTS: In 100% (300/300) of fingers and thumbs, the FDP and FPL tendons were made up of two parallel bundles arranged side by side, with a central vertical septum between these two hemitendons, starting at the head of the proximal phalanx (PP) and continuing distally. This central septum was always present starting at the proximal third of PP for the FDP of the index, middle, and ring fingers. The septum was more difficult to identify in the thumb and little finger. Cohen's kappa indicated near perfect agreement when all digits were considered together (≥ 0.9), and substantial agreement for the thumb (0.71) and for the little finger (0.82). CONCLUSIONS: With US imaging, the bifascicular nature of the FDP and FPL tendons is easy to see, as these tendons have a double-barreled configuration starting at the head of the proximal phalanx. KEY POINTS: •Analysis of anatomical slices of the hand tendons found a bifascicular appearance of the flexor digitorum profundus and flexor pollicis longus tendons starting at the head of the proximal phalanx. •This distinct feature of two hemitendons arranged side by side was seen in 100% of tendons we examined with US. It is associated with a vertical central septum that causes anisotropy. •Awareness of this "forgotten" anatomical detail has practical implications when interpreting images generated by latest-generation US systems and during surgery on hand flexor tendons.

Correlation between quantitative and semiquantitative magnetic resonance imaging and histopathology findings in dermatomyositis.

OBJECTIVES: The aim of this study was to compare muscle biopsy findings, as well as clinical and analytical features, with those of magnetic resonance imaging (MRI) studies of muscle in patients with dermatomyositis. METHODS: All patients from the Longitudinal Myopathy Cohort of the Hospital Clínic de Barcelona were prospectively included in the study from 2009 to 2016. MRI images of muscle and fascial oedema were compared with muscle pathology results using both quantitative and semi-quantitative scores. RESULTS: We found a statistically significant association between the inflammatory infiltrate and both muscle (r2=0.54, p=0.001) and fascial oedema (r2=0.54, p<0.001). In addition, muscle oedema was significantly associated with punched-out vacuoles (p=0.04) and muscle enzymes in serum (r2=0.34, p=<0.01 for CK and r2=0.22, p<0.05 for aldolase). The number of treatment drugs received at the time of MRI was inversely associated with the number of muscle inflammatory cells in the biopsy and with both muscle and fascial oedema (all p<0.05). CONCLUSIONS: Key MRI findings correlate with the main features of dermatomyositis muscle biopsy results, suggesting that MRI findings could be used as a surrogate marker of disease activity.

US-guided percutaneous release of the first extensor tendon compartment using a 21-gauge needle in de Quervain's disease: a prospective study of 35 cases.

PURPOSE: To evaluate the efficacy of ultrasonography-guided percutaneous treatment of de Quervain tenosynovitis with the combination of a corticosteroid injection and release of the retinaculum of the first extensor compartment tendons with a 21-gauge needle. MATERIALS AND METHODS: The first part of our study consisted of ten procedures on cadaver wrists followed by dissection to analyse the effectiveness of the retinaculum release and detect any collateral damage. The second part was a prospective clinical study of 35 procedures. Outcomes were evaluated through a 6-month clinical follow-up and telephone interview at the end of the study. The following parameters were monitored over time: pain level on a visual analogue scale, the QuickDASH and the PRWE. Patient satisfaction questionnaires were also administered. RESULTS: No complications were found during the cadaver study. However, the release was confirmed as 'partial' in all wrists. In the clinical portion of this study, significant improvement was observed in 91.4 % of cases (32/35) within 1 month and the results were stable until the end of the study; all of these patients avoided surgery. The release procedure failed in three patients who eventually required surgical treatment. CONCLUSION: US-guided partial release and simultaneous corticosteroid injection for treatment of de Quervain's disease using a 21-gauge needle is feasible in current practice, with minimal complications. KEY POINTS: • Ultrasound-guided treatment of de Quervain's disease is feasible with a 21G needle. • There was notable regression of clinical signs in 91.4 % of cases. • The procedure is very safe, no iatrogenic neurovascular or tendinous injuries occurred. • Our procedure requires only one session and 3 days away from work.

Prevalence and characteristics of intravertebral enhancement on contrast-enhanced CT scans in cancer patients.

STUDY DESIGN: This was a single center, retrospective observational study. OBJECTIVE: to investigate-in a cancer population-the prevalence and hallmarks of intravertebral enhancement (IVE) detected on contrast-enhanced CT. SUMMARY OF BACKGROUND DATA: Intravertebral enhancements secondary to iodinated contrast stagnation have been described. Cancer patients have an increased risk of perivertebral venous thrombosis or stenosis secondary to several risk factors (cancer or drug induced hypercoagulability, deterioration of venous flow linked to catheter insertion, prolonged immobilization). In case of a high density lesion identified on CT, the diagnostic choice between metastasis and contrast media within bone marrow vessels may be an issue, especially as oncologic follow-up CT scans are usually performed with contrast medium injection. METHODS: 2572 contrast-enhanced body CT scans performed in cancer patients over 3 months in the medical imaging department of a university hospital were retrospectively reviewed. IVE was sought when paravertebral venous collateral circulation was detected and bone metastasis ruled out and classified as linear or nodular. Their locations within vertebra, their relation to the injection side and the predominant collateral venous network side were evaluated. RESULTS: Sixty-seven (2.8%) patients had a collateral paravertebral venous system and among them 21 had IVE (37%). There were 208 IVE locations involving 75 vertebrae. 199 IVE were linear-shaped (95.7%) and 9 nodular-shaped (4.3%). 80.8% were located between C6 and T4. 88.9% were localized in the vertebral body. 73.1% were located medially or ipsilateral to the injection side. CONCLUSION: Intravertebral enhancement is found in 37% of the patients with paraspinal collateral venous circulation when a CT scan is performed for cancer. The ipsilateral or medial position of the IVE relative to the injection side and the side of the dominant perivertebral venous system, and the possibility of connecting the IVE to a paravertebral vein may be in favor of vascular opacification.