Test yourself: question and answer question: painful knee swelling

Test yourself answer: painful knee swelling

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Diagnostic accuracy of imaging modalities in the detection of clinically diagnosed de Quervain’s syndrome: a systematic review Abstract Objectives To collate and synthesise the literature to provide estimates of the diagnostic accuracy of imaging modalities, and summarise the reported imaging findings associated with de Quervain’s syndrome. Materials and methods A systematic search was performed in seven databases (MEDLINE, EMBASE, CINAHL, Cochrane Library, PROSPERO, Web of Science, and ProQuest Dissertations & Theses Global). Two reviewers independently performed screening, data extraction and quality assessment using a modified Quality Assessment of Diagnostic Accuracy Studies-2. Measures of diagnostic accuracy were summarised for different modalities and imaging findings. Results Twenty-two studies were included, reporting ultrasound, magnetic resonance imaging, X-ray and scintigraphy findings. Reported imaging findings included sheath effusion, retinaculum thickening, subcutaneous oedema, tenosynovitis, hypervascularity, increased tendon size, bony erosion, apposition, calcific lesions and increased uptake on scintigraphy. The most commonly reported imaging findings related to the tendon sheath, with a sensitivity ranging from 0.45 to 1.00 for thickening, and 0.29 to 1.00 for effusions. The risk of bias of studies is largely unclear owing to a lack of reported detail. Conclusions The accuracy of imaging in the diagnosis of de Quervain’s syndrome is unable to be determined because of the quality of the studies included. Ultrasound is the most frequently studied imaging modality and may be the modality of choice in clinical practice. Further research involving both symptomatic and asymptomatic participants and clear definitions of abnormal findings are required to better evaluate the effectiveness of imaging in identifying de Quervain’s syndrome.

Magnetic resonance imaging of the quadriceps tendon autograft in anterior cruciate ligament reconstruction Abstract Background Quadriceps tendon (QT) autograft is emerging as a popular technique for primary anterior cruciate ligament (ACL) reconstruction. Studies have shown that it has comparable outcomes to bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autografts while mitigating post-operative complications associated with these grafts. Purpose To provide a literature summary of the important pre- and post-operative magnetic resonance imaging (MRI) findings of the quadriceps tendon and pertinent postoperative complications associated with the QT harvest. Radiologists should be familiar with MR findings after autologous graft harvest of the quadriceps tendon for reconstruction of the ACL. Level of evidence Level IV.

Ultrasound-guided percutaneous release of the carpal tunnel: comparison of the learning curves of a senior versus a junior operator. A cadaveric study Abstract Objective The purpose was to evaluate, in a cadaveric cohort, the feasibility and the learning curve of ultrasound-guided percutaneous carpal tunnel release. Materials and methods Fourteen carpal tunnel releases were carried out on unembalmed cadavers by a senior and a junior radiologist. Procedures were realized with an 18-MHz linear probe. An anatomical evaluation was first performed using ultrasound to detect any anatomical variant. After hydrodissection of the carpal tunnel with lidocaine, a 3-mm hook knife was introduced into the security zone to perform a retrograde section of the transverse carpal ligament (TCL) under ultrasound guidance. Anatomical dissection was performed for each wrist. The main evaluation criterion was the complete TCL section. The procedure duration (minutes), skin incision size (millimeters), the integrity of the median nerve, thenar motor branch, and palmar vascular arch were also evaluated. Results The senior operator was able to perform a complete release after training on three specimens and the junior operator after four specimens (p > 0.05). In most of the cases when complete release was not achieved, it was due to an incomplete section of the distal TCL (10 mm missing section on average). Mean duration time of procedure was 14 min (11 min for the senior versus 17 min for the junior, p > 0.05). Damage of neither the median nerve nor the vascular structure was observed. Mean size of the skin incision was 3 mm. Conclusion The ultrasound-guided percutaneous release of the carpal tunnel is demonstrated to be a procedure with a rapid learning curve.

Diagnostic accuracy of MRI for detection of tears and instability of proximal long head of biceps tendon: an evaluation of 100 shoulders compared with arthroscopy Abstract Objective To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) for detection of instability and tears of the proximal long head of biceps tendon (LHBT). To assess intraobserver and interobserver agreement. Materials and methods We performed a retrospective analysis of prospectively collected data of 100 consecutive shoulders who underwent non-contrast 1.5-T MRI prior to arthroscopic surgery due to rotator cuff injury. Images were independently analyzed by two musculoskeletal radiologists. LHBT was evaluated for presence of tearing (intact, longitudinal split, partial-thickness, or full-thickness) and position (normal, subluxated, and dislocated). Anterosuperior rotator cuff tears were also assessed. The reference standard was arthroscopic surgery. The ramp test was performed in order to evaluate LHBT stability. Diagnostic performance measures were determined and Kappa coefficients assessed agreement. Results Concerning the detection of overall tears, sensitivity ranged from 71 to 73% and specificity was 73%. The specificity for full-thickness tears ranged from 75 to 96%. Overall displacement showed sensitivity ranging from 51 to 58% and specificity ranging from 70 to 86%. The specificity of overall displacement combined with anterosuperior rotator cuff tears ranged from 73 to 91%. Interobserver Kappa values were between 0.59 and 0.69. Intraobserver Kappa values were between 0.74 and 0.82. Conclusions MRI has moderate accuracy and good agreement for detection of LHBT tears and instability. There is a tendency for increased specificity for full-thickness tears and for instability in the coexistence of anterosuperior rotator cuff tears.

Evaluation of giant cell tumors by diffusion weighted imaging–fractional ADC analysis Abstract Background A single ADC value is used in clinical practice on multi b-value acquisitions. Low b-value acquisitions are affected by intravoxel incoherent motion, which is dependent on perfusion. Giant cell tumors (GCTs) are known to exhibit early arterial enhancement and low ADC values. Mean, minimum and fractional ADC characteristics of osseous and tenosynovial GCTs are systematically evaluated. Methods Tenosynovial and osseous GCTs were included. Each lesion was evaluated on conventional MRI and DWI by two musculoskeletal radiologists. ADC was measured by placing an ROI on the most confluent enhancing portion of the lesion. Fractional and best fit ADC calculations were performed using MATLAB software. Results No statistically significant difference was found between tenosynovial and osseous lesions’ ADC values. Mean ADC for all lesions was 1.0 × 10−3 mm2/s (SD = 0.2 × 10−3 mm2/s) and minimum ADC was 0.5 × 10−3 mm2/s (SD = 0.3 × 10−3 mm2/s). Average mean ADC value obtained from B50–B400 slope was 1.1 × 10−3 mm2/s (SD = 0.2 × 10−3 mm2/s), and the average mean ADC value obtained from B400–B800 slope was 0.8 × 10−3 mm2/s (SD = 0.1 × 10−3 mm2/s) [p-value <0.01]. Conclusion Tenosynovial and osseous GCTs demonstrate similar and low ADC values, which become even lower when using high b-value pairs. Our study also supports the theory of intravoxel incoherent motion that becomes apparent at low b values as related to giant cell tumors, which are known to be hyperperfused.

Pearls and pitfalls of fluoroscopic-guided foot and ankle injections: what the radiologist needs to know Abstract Objective This article provides a comprehensive, joint-by-joint review of fluoroscopic-guided foot and ankle injections and emphasizes pre-procedural planning, relevant anatomy, appropriate technique, troubleshooting the difficult procedure, and the importance of communicating unexpected findings with the referring clinician. The interrogation of pain generators including variant ossicles, fractures, and post-surgical/traumatic findings is also described. Conclusions Even the most challenging foot and ankle injections may be successfully completed with a solid anatomical understanding and thoughtful approach.

Validity of the alpha angle measurements on plain radiographs in the evaluation of cam-type femoroacetabular impingement in patients with slipped capital femoral epiphysis Abstract Objective The purpose of the study was to investigate the correlation of two different alpha angle (a-angle) measurements (“anatomical method and “three-point method”) with the anterior offset ratio (AOR), femoral head ratio (FHR), and lateral femoral head ratio (LFHR) in patients with slipped capital femoral epiphysis (SCFE). Materials and methods We included 39 hips of 26 patients. The a-angles were measured on the frog-leg lateral view (Lat) and anteroposterior (Ap) view, FHR was measured on the Ap view, and LFHR and AOR were measured on the Lat view. A t test was performed to analyze the means of the alpha angles measured using the three-point method and the anatomical method, and also, a correlation was conducted to assess the association of the a-angles among the FHR, LFHR, and AOR. Results The mean a-angles in the Ap plane in the three-point method and anatomical method were 76° ± 15° and 64° ± 10° respectively (p < 0.001). The mean a-angles in the Lat plane in the three-point method and anatomical method were 67° ± 13° and 56° ± 11° respectively (p < 0.001). The AOR showed a significant correlation only with the anatomical method a-angle values in the Lat plane (p = 0.026). The a-angles in the three-point method in the Lat plane did not show any significant correlation with the AOR, FHR, and LFHR. Both the FHR and LFHR values correlated significantly with the Ap plane a-angles in the three-point method and anatomical method. However, none of these correlations was strong. Conclusions The a-angle measurement methods described in patients without femoral head–neck axis disruption may not be valid in patients with a disorder such as SCFE.