RPS 1710 - Upper extremities and facial bones

Purpose:

The Bristow-Latarjet operation (coracoid translocation), which has developed different variations, is an effective treatment of shoulder recurrent dislocation. Our research is to investigate the merit and demerit of these variations by analysing CT images in a 1-year follow-up.

Methods and materials:

200 patients with shoulder recurrent dislocation who had a Bristow-Latarjet operation in our hospital were involved. They were divided into 6 groups. 25 cases were bone block fixed with anchor (G1), 52 cases inlay with single screw (G2), 15 cases no-inlay with single screw (G3), 67 cases inlay with single pair of buttons (G4), 14 cases with double screws (G5), and 27 cases with double pairs of buttons (G6). The size of bone block and un-union were evaluated in CT on the postoperative day, and at 3, 6, and 12 months.

Results:

The increase of step below articular surface compared to postoperative day: G2>G4 in 3 months (p<0.05); G6>G1, G2, and G4 while G2>G4 in 6 months (p<0.05); G6>G1, G2, G3, and G4 in 12 months (p<0.05). The decrease of bone length along the tunnel: G1, G4, and G6>G2 while G6>G3, G4, and G5 in 6 months (p<0.05); G1, G4, and G6>G2 while G6>G3 in 12 months (p<0.05). The un-union rates in 3 months were 70% (significantly high), 2.73% (significantly low), 50%, 17.2%, 45.5%, and 30.4%, but were not significantly different in other stages.

Conclusion:

Bone block absorption perpendicular to the articular was more after fixed with a single screw rather than buttons inlay and with double pairs of buttons rather than single fixation and anchor. Bone block absorption along the tunnel was more after fixed with buttons than a screw and with a single pair of buttons than double. Bone block un-union happened more in the early stage after fixed with anchor and less after fixed with a single screw inlay.

Limitations:

A limited number of cases in some groups.

Ethics committee approval

n/a

Funding:

No funding was received for this work.

Purpose:

To test the hypothesis that Jaccoud arthropathy (JA) in systemic lupus erythematosus (SLE) patients is associated with abnormal extensor digitorum (ED) tendons displacement during flexion of the metacarpophalangeal (MCP) joints.

Methods and materials:

16 SLE patients with JA (JA+), 12 SLE patients without JA (JA-), and 24 control subjects were included in the study. Transverse spin-echo T1-weighted MR sequences of the MCP joints in flexion and in extension were obtained in each hand of SLE patients and in one randomly-selected hand of control subjects. Two radiologists separately measured the amplitude and the direction of the displacement of the ED tendons with respect to the midline at the level of the MCP joints. Statistical analysis included two-way ANOVA with random effects to assess differences in amplitude (p<0.0083), Fisher-Freeman-Halton's exact test to assess differences in direction (p<0.0063), and Gwet’s AC1 score to determine interobserver agreement.

Results:

The amplitude of the displacement of the ED tendons was statistically significantly higher in JA+ patients than JA- patients and controls in flexion for both readers (p<0.0001) and in extension for one reader (p<0.0048). Ulnar deviation of the ED tendons was statistically significantly more frequent in JA+ patients than in JA- patients and controls in flexion and in extension for both readers (p<0.0001).

Conclusion:

JA is associated with the abnormal displacement of the ED tendons in flexion and extension. Abnormal displacement of the ED tendons is absent in patients without JA.

Limitations:

In the absence of anatomical correlation, we are unable to precisely determine the anatomic lesions associated with the instability of the ED tendons.

Ethics committee approval

This study was approved by our institutional ethics committee. All study participants provided written informed consent.

Funding:

No funding was received for this work.

Purpose:

Ultrasonography (USG) is a reliable, inexpensive, readily available, and painless modality for the diagnosis of carpal tunnel syndrome. However, the main sonographic criteria of the cross-sectional area (CSA) of the median nerve shows a wide normal variation depending on regional and ethnical differences, which warrants the establishment of the normal range of variability in the dimensions of the median nerve in the local population. In our experience, the normal average cross-sectional area of the median nerve in the asymptomatic adult Asian population is relatively small compared to other populations worldwide.

Methods and materials:

500 asymptomatic patients/1,000 median nerves were evaluated by high-resolution USG using Toshiba Aplio 500 at the distal wrist crease and mid-forearm 12 cm above the distal wrist crease by 3 expert radiologists independently over a period of 2 years (July 2017-July 2019).

Results:

The median nerve CSA in our population at the right wrist was 6.8±1.9 mm2 while at the left wrist was 6.6±1.9 mm2. The CSA at the right forearm was 5.3 ± 1.4 mm2 while at the left forearm was 5.2±1.5 mm2 (P<0.001). Also, the CSA was relatively larger in males than females.

Conclusion:

The CSA of the median nerve at the wrist and forearm in the Asian population is relatively smaller compared to other populations worldwide. This further enforces the idea to define normal reference range for CSA of the median nerve by obtaining normative data for our population.

Limitations:

Only Pakistani asymptomatic adults included. Results should be correlated with other available Asian population data as well as data available worldwide for better reference range determination.

Ethics committee approval

Approved by our institutional review board.

Funding:

No funding was received for this work.

Purpose:

To evaluate the feasibility and to compare image quality and diagnostic performance of 3T and 7T magnetic resonance imaging (MRI) protocols for the direct depiction of finger pulley ruptures using anatomic preparation as the reference.

Methods and materials:

30 fingers from 10 human cadavers were examined at 3T and 7T before and after being subjected to single and multiple iatrogenic pulley ruptures. MRI protocols were comparable in duration. Two experienced radiologists evaluated the MRIs and defined the location and morphology of finger pulley lesions. Image quality was graded according to a 4-point Likert scale. The diagnostic performance was assessed with anatomic preparation as a gold standard. Interobserver agreement was calculated using Cohen's Kappa coefficients (κ).

Results:

In a comparison of 7T versus 3T sensitivity and specificity for the detection of A2, A3 and A4 pulley lesions were comparable with 100% versus 95%, respectively, 98% versus 100%. In the assessment of A3 pulley lesions sensitivity of 7T was superior to 3T MRI (100% vs 83%), whereas specificity was lower (95% vs 100%). Image quality assessed before and after iatrogenic rupture was comparable with 2.74 for 7T and 2.61 for 3T, reflecting adequate image quality in average, whereas the visualisation of the A3 finger flexor pulley before rupture creation was significantly better for 7T (p<0.001). Interobserver variability was substantial at 7T (κ=0.90) and 3T (κ=0.80).

Conclusion:

MRI at 3T and 7T allows direct visualisation and characterisation of traumatic A2, A3, and A4 pulley lesions with higher agreement rates for 7T. High-field MRI is a modern approach for the pre-surgical evaluation compared to indirect techniques such as ultrasound depending of bowstringing.

Limitations:

An ex-vivo cadaver study.

Ethics committee approval

Ethics commettee approval was obtained from Friedrich-Alexander-University Erlangen-Nuremberg, Germany (260_15 Bc).

Funding:

No funding was received for this work.

Purpose:

Computed tomography (CT) features are the reference standard in evaluating the ossification process of the medial clavicular epiphysis for forensic age diagnostics in adolescents and young adults. Consequently, the highest efforts on radiation reduction are warranted. Therefore, the aim of this study was to investigate the feasibility of low-dose CT of the clavicula for age estimation.

Methods and materials:

207 non-contrast chest CT of 144 patients born between 1988–2012, performed in 2018 due to various clinical indications, were included in this retrospective study. The mean patient age was 16.9±6.6 years. Patients were divided into a low-dose (LD; n=146) and high-dose (HD; n=61) group. Image quality and ossification stages (using the 5-stage classification including the subgroups 2a-3c) were assessed by two radiologists independently. Confidence levels were evaluated for subgroups 2a-3c. Radiation dose was determined via dosimetry software.

Results:

A dose simulation with a z-axis reduction to depict the clavicula only resulted in a median exposure of 0.1 mSv (IQR: 0.0) in LD compared to 0.9 mSv (IQR: 0.6) in HD (p<0.001). The median image quality was rated significantly worse in LD compared to HD with a median of 3 (IQR: 1) versus 4 (IQR: 0) by both readers on a Likert-scale ranging from 1-4 (p<0.001 for both readers). There was an almost perfect agreement for the ossification stages between both readers with a Cohen's kappa of 0.83 (p<0.001). Median confidence levels of both readers were not significantly different between LD and HD (reader 1: p=0.186; reader 2: p=0.074).

Conclusion:

Low-dose CT of the clavicula for age estimation is possible without a loss of confidence.

Limitations:

No randomisation regarding scanning protocol was performed due to the retrospective character.

Ethics committee approval

IRB approval obtained. Informed consent waived.

Funding:

No funding was received for this work.

Purpose:

Specific personal identification (fingerprint or DNA matching) is strong evidence in forensic examinations but is mostly lost with decomposition. Sutures on skulls are commonly preserved. The morphology of frontonasal sutures varies among individuals and can be clearly demonstrated by three-dimensional CT (3DCT) images using a new rendering technique. Cinematic volume rendering is a new technique which improves the clarity of 3DCT images and can display skull sutures. We asked whether 3DCT images of the frontonasal suture created by the cinematic volume rendering technique can be used as specific personal identification.

Methods and materials:

CT images of 50 dry skulls were reformatted to 3DCT images by using a cinematic volume rendering technique on a commercially available workstation (syngo.via, version VB20). Photographs of the dry skulls were adjusted by a blurring effect on Photoshop. Four readers (an anatomist, forensic anthropologist, forensic doctor, and radiologist) responded to three questionnaires, firstly matching a 3DCT image with the photographs of dry skulls, secondly determining minimum levels of clarity of the suture on dry skull photographs that they can use for matching, and thirdly determining the level of clarity which 3DCT displayed using photographs of dry skulls as a reference.

Results:

Correct matching rates were high for all readers (98-100%). The mean values of visual grading analysis scores for clarity of the sutures on 3DCT (63-77%) are higher than that of the minimum level that each reader required for matching (37-50%) (p<0.001, p=0.0039).

Conclusion:

3DCT images of the frontonasal suture created by cinematic volume rending can be used for personal identification. If a clinical CT of the skull of a missing person is available, 3DCT images can be later reformatted and used as pre-mortem data.

Limitations:

n/a

Ethics committee approval

n/a

Funding:

No funding was received for this work.

Purpose:

To investigate differences in perfusion-MRI parameters between healthy and pathologic regions in patients with a histologically confirmed medication-related osteonecrosis of the jaw (MRONJ).

Methods and materials:

in a retrospective analysis, standard parameters of dynamic contrast-enhanced (DCE) perfusion MRI of 22 patients, who received the examinations as part of a dedicated clinical MRI protocol for MRONJ assessment, were evaluated. Same sized regions of interest were placed into a representative bone of defined regions. All regions were assessed qualitatively by a blinded expert radiologist as ground truth (4-point Likert-scale; normal, mild-severe changes). Furthermore, histologic confirmation was present for the resected regions.

Results:

The mean patient age was 75.2 years (+/- 9.9; 12 female patients). Wash-in (0.15 vs 0.05) and positive enhancement integral (PEI; 0.17 vs 0.11) values were significantly higher in MRONJ-affected regions than in healthy jaw areas (p<0.05 for both). Furthermore, DCE-parameters partially correlated with qualitative expert ratings (wash-in, PEI, initial area under the curve, all p<0.05).

Conclusion:

DCE-MRI reveals significantly different bone perfusion in MRONJ-affected regions of the mandible and maxilla compared to the healthy jaw. Disease extent according to MRI data was larger than visible necrotic areas during clinical examination and may help to evaluate the severity of this adverse drug effect.

Limitations:

This is a retrospective single-centre and single-scanner investigation. All perfusion data was retrieved from MRONJ-diagnosed patients. While clinical and radiological assessment did not indicate pathologic alterations in regions defined as healthy, possible subvisual alterations of the healthy jaw may represent a limitation. However, a control-cohort of healthy volunteers was not used for ethical reasons.

Ethics committee approval

Written consent by all patients and IRB approval was given.

Funding:

No funding was received for this work.

Purpose:

To investigate whether the repaired tendon thickness and sub-deltoid fluid collection after rotator cuff repair, which was seen on follow-up ultrasound (US), are correlated with clinical outcome and to assess whether these factors lead to different clinical outcomes depending on the surgical method.

Methods:

This retrospective study included 54 patients who underwent supraspinatus tendon repair with a suture-bridge or single-row technique and follow up US. Two radiologists independently measured the thickness of the repaired supraspinatus tendons and fluid collection in sub-deltoid space. We assessed the relationship between the sonographic parameters, including repaired supraspinatus tendon thickness and sub-deltoid fluid collection, with the clinical outcome represented by the Korean shoulder scoring system (KSS) score using correlation coefficients (R).

Results:

There was a significant relationship between sub-deltoid fluid collection and the pain of the patients (p≤0.05), although every category showed an inverse relationship with the fluid thickness. The ICC values for sonographic imaging parameters between interpreters ranged from 0.910 to 0.946, showing excellent reproducibility.

Conclusion:

Sub-deltoid fluid collection of repaired supraspinatus tendons measured on postoperative US can be a useful method in predicting the patient’s subjective clinical outcome, especially pain, regardless of age or surgical technique.
Limitations: This was a retrospective study. The measurement of sonographic parameters was based on captured images that had been taken prior to assessment and therefore it was not a real-time measurement.

Ethics:

n/a

Funding:

No funding was received for this work.