Comparison of early migration patterns between a ceramic and polyethylene liner in uncemented Trabecular Titanium cups: a 2-year randomized controlled trial of 52 hips using radiostereometric analysis.

BACKGROUND AND PURPOSE: Ceramic liners may reduce early stability of uncemented acetabular components due to higher stiffness. However, the bone ingrowth capacities of porous trabecular titanium might compensate for this effect. This prospective randomized trial quantifies migration patterns of the Delta-TT cup, and compares polyethylene and ceramic liners. PATIENTS AND METHODS: Patients undergoing primary uncemented total hip arthroplasty with the Delta-TT cup and femoral stem with ceramic head were randomized to a polyethylene (n = 25) or ceramic (n = 28) liner. Radiostereometric analysis (RSA) radiographs, patient-reported hip function (HOOS-PS, OHS), and quality of life (EQ5D) were collected at baseline and 1.5, 3, 6, 12, and 24 months postoperatively. Model-based RSA was used to calculate 3D cup translation and rotation, and mixed models were used to compare effects over time between groups. RESULTS: At 2 years follow-up, Delta-TT cups showed similar mean proximal translation of 0.56 mm (95% CI 0.38-0.75) in the ceramic (CE) group and 0.54 mm (0.30-0.77) in the polyethylene (PE) group, with a between group effect of 0.02 mm (-0.20-0.23). Most cup migration occurred in the first 1.5 to 3 months, stabilizing within 6 months. Any between-group effects were ≤ 0.30 mm for translation and ≤ 0.45° for rotation. Improvements in patient-reported hip function and quality of life were similar in both groups. INTERPRETATION: Regardless of liner type, Delta-TT cups showed some initial migration and stabilized within 6 months, which seems promising for long-term fixation in both cup-liner constructs.

Ten percent re-dislocation rate 13 years after the arthroscopic Bankart procedure.

PURPOSE: The aim of the present study was to determine the long-term outcome after the arthroscopic Bankart procedure, in terms of recurrent instability, shoulder function, glenohumeral arthropathy and patient satisfaction. METHODS: Patients who underwent the arthroscopic Bankart procedure between January 1999 and the end of December 2005 were invited to complete a set of Patient Reported Outcome Measures (PROMs) and visit the hospital for clinical and radiological assessment. PROMs included the Western Ontario Shoulder Instability Index (WOSI), the Oxford Shoulder Instability Score (OSIS) and additional questions on shoulder instability and patient satisfaction. Clinical assessment included the apprehension test and the Constant-Murley score. The Samilson-Prieto classification was used to assess arthropathy on standard radiographs. The primary outcome was a re-dislocation that needed reduction. Secondary outcomes in terms of recurrent instability included patient-reported subluxation and a positive apprehension test. RESULTS: Of 104 consecutive patients, 71 patients with a mean follow-up of 13.1 years completed the PROMs, of which 53 patients (55 shoulders) were also available for clinical and radiological assessment. Re-dislocations had occurred in 7 shoulders (9.6%). Subluxations occurred in 23 patients (31.5%) and the apprehension test was positive in 30 (54.5%) of the 55 shoulders examined. Median functional outcomes were 236 for WOSI, 45 for OSIS, and 103 for the normalized Constant-Murley score. Of all 71 patients (73 shoulders), 29 (39.7%) reported being completely satisfied, 33 (45.2%) reported being mostly satisfied and 8 (11%) reported being somewhat satisfied. Glenohumeral arthropathy was observed in 33 (60%) of the shoulders. CONCLUSION: Despite 10% re-dislocations and frequent other signs of recurrent instability, shoulder function and patient satisfaction at 13 years after arthroscopic Bankart repair were good. LEVEL OF EVIDENCE: Level IV.

The quantification of glenoid bone loss in anterior shoulder instability; MR-arthro compared to 3D-CT.

OBJECTIVE: The purpose of this study is to investigate if magnetic resonance imaging with intra-articular contrast (MR-arthro) is as reliable as three-dimensionally reconstructed computed tomography imaging (3D-CT) in quantifying the glenoid bone loss in patients with anterior shoulder instability. MATERIALS AND METHODS: Thirty-five patients were included. Sagittal MR-arthro and 3D-CT images of the glenoid surface were obtained pre-operatively. Two observers measured these images twice with OsiriX software in a randomized and blinded way. The intraclass correlations (ICC) of the intra- and inter-observer reliability within one method and an additional Bland-Altman plot for calculating agreement between the two methods were obtained. RESULTS: The joint estimates of the intra-observer reliability, taking into account the data from both observer A and B, for 3D-CT and MR-arthro were good to excellent. The intra-observer reliability was 0.938 (95% CI: 0.879, 0.968) for 3D-CT and 0.799 (95% CI: 0.639, 0.837) for MR-arthro. The inter-observer reliability between the two observers within one method (3D-CT or MR-arthro) was moderate to good. 3D-CT: 0.724 (95% CI: 0.236, 0.886) and MR-arthro: 0.534 (95% CI: 0.128, 0.762). Comparing both the 3D-CT and MR-arthro method, a Bland-Altman plot showed satisfying differences with the majority of outcomes (89%) within 1 SD. CONCLUSIONS: Good to excellent intra- and moderate to good inter-observer correlations and a satisfying Bland-Altman plot when compared to 3D-CT show tendencies that MR-arthro is reliable and valid for measuring bony defects of the glenoid.

Detection of partial-thickness supraspinatus tendon tears: is a single direct MR arthrography series in ABER position as accurate as conventional MR arthrography?

PURPOSE: The purpose of this study was to retrospectively evaluate sensitivity and specificity of a single magnetic resonance (MR) arthrography series in abduction external rotation (ABER) position compared with conventional MR arthrography for detection of supraspinatus tendon tears, with arthroscopy as gold standard, and to assess interobserver variability. MATERIALS AND METHODS: Institutional review board approval was obtained; informed consent was waived. MR arthrograms of 250 patients (170 men and 80 women; mean age, 36 years) were retrospectively and independently evaluated by three observers. Oblique coronal T1-weighted fat-suppressed images, proton density, and T2-weighted images and axial T1-weighted images and oblique sagittal T1-weighted fat-suppressed images were analyzed to detect supraspinatus tendon tears. Separately, a single T1-weighted fat-suppressed oblique axial series in ABER position was evaluated. Both protocols were scored randomly without knowledge of patients' clinical history and arthroscopy results. Tears were subclassified, based on articular surface integrity and extension (Lee classification). Interobserver agreement was assessed by kappa statistics for all patients. Ninety-two of 250 patients underwent arthroscopy; sensitivity and specificity of ABER and conventional MR arthrography were calculated and compared using paired McNemar test. RESULTS: Weighted kappa values of ABER and conventional MR arthrography were 0.48-0.65 and 0.60-0.67, respectively. According to arthroscopy, 69 of 92 patients had an intact cuff, and 23 patients had a cuff tear (16 partial thickness and seven full thickness). There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (48-61% and 52-70%, respectively) and specificity (80-94% and 91-95%). CONCLUSION: Sensitivity and specificity of a single T1-weighted series in ABER position and conventional MR arthrography are comparable for assessment of rotator cuff tears.

Is a single direct MR arthrography series in ABER position as accurate in detecting anteroinferior labroligamentous lesions as conventional MR arthography?

PURPOSE: The purpose of this study is to retrospectively compare accuracy of single magnetic resonance (MR) arthrography series in Abduction External Rotation (ABER) with conventional MR arthrography for detection and characterisation of anteroinferior labroligamentous lesions, with arthroscopy as reference standard. Inter-observer variability of both protocols was determined. METHODS AND MATERIALS: Institutional review board approval was obtained; informed consent was waived. MR arthrograms, including oblique axial fat suppressed T1-weighted images in ABER position and conventional imaging directions of 250 patients (170 men, 80 women; mean age, 36 years), were retrospectively and independently evaluated by three reviewers. Reviewers were blinded to clinical information and arthroscopic results. Labroligamentous lesions were registered in both ABER and MRa. The lesions were sub-classified (Bankart, Perthes, anterior labrum periosteal sleeve avulsion (ALPSA) or lesions not otherwise specified). Inter-observer agreement was assessed by Kappa statistics for all 250 patients. Ninety-two of 250 patients underwent arthroscopy. Sensitivity, specificity and accuracy of ABER versus conventional MR arthrography were calculated and compared using paired McNemar test. RESULTS: Kappa values of the ABER and conventional MR arthrography ranged from 0.44 to 0.56 and 0.44 to 0.62, respectively. According to arthroscopy, 45 of 92 patients had an intact anteroinferior labrum, and in 44 patients, a labroligamentous lesion (eight Bankart, seven Perthes, 29 ALPSA and three lesions not otherwise specified) was diagnosed. There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (85-89%, 89-96%), specificity (82-91%, 84-89%) and overall accuracy (50-62%, 53-63%). CONCLUSION: The results of a single MR arthrography series in ABER position are comparable with those of conventional MR arthrography for detecting anteroinferior labroligamentous lesions.

Quantification of a glenoid defect with three-dimensional computed tomography and magnetic resonance imaging: a cadaveric study.

Bone loss of the glenoid is a common finding in anterior glenohumeral instability. Several methods to measure the size of a glenoid defect have been described but have not been validated. In this study, 14 cadaver glenoids with a randomly created anteroinferior glenoid defect were used for validation of the so-called circle method. Measurements were done by 2 researchers on digital photographs, 3-dimensional (3D) computed tomography (CT) scans, and magnetic resonance images (MRI). The correlation coefficient (r(2)) for comparing measurements from the digital photographs with the CT scans was 0.97 for researcher 1 and 0.90 for researcher 2. When they compared digital images with MRI, the r(2) was 0.93 for researcher 1 and 0.92 for researcher 2. No statistical differences were found between the 2 researchers. The circle method is a simple method for preoperative quantification of a glenoid defect. Measurements can be done with 3D CT scans as well as MRI.

MRI in evaluating atrophy of the external anal sphincter in patients with fecal incontinence.

OBJECTIVE: External anal sphincter atrophy seen at endoanal MRI may predict poor outcome of surgical anal sphincter repair for an external anal sphincter defect. The purposes of this study were to compare external phased-array MRI to endoanal MRI for depicting external anal sphincter atrophy in patients with fecal incontinence and to evaluate observer reproducibility in detecting external anal sphincter atrophy with these techniques. SUBJECTS AND METHODS: Thirty patients with fecal incontinence (23 women, seven men; mean age, 58.7 years; age range, 37-78 years) underwent both endoanal and external phased-array MRI. Images were evaluated for external anal sphincter atrophy by three radiologists. Measures of differences and agreement between both MRI techniques and of interobserver and intraobserver agreement of both techniques were calculated. RESULTS: The MRI techniques did not significantly differ in their ability to depict external anal sphincter atrophy (p = 0.63) with good agreement (kappa = 0.72). Interobserver agreement was moderate (kappa = 0.53-0.56) for endoanal MRI and moderate to good (kappa = 0.55-0.8) for external phased-array MRI. Intraobserver agreement was moderate to very good (kappa = 0.57-0.86) for endoanal MRI and fair to very good (kappa = 0.31-0.86) for external phased-array MRI. CONCLUSION: External phased-array MRI is comparable to endoanal MRI in depicting external anal sphincter atrophy and, thereby, in selecting patients for anal sphincter repair. Because results among interpreters varied considerably depending on the experience level, both techniques can be recommended in the diagnostic workup of fecal incontinence only if sufficient experience is available.

Ramus circumflexissimus--a rare coronary anomaly detected by coronary computed tomography angiography.

We present a case of L-1 type solitary (left) coronary artery that was detected with coronary computed tomography angiography and confirmed by invasive coronary angiography in a female patient with atypical chest pain. Solitary coronary artery anomalies are rare. The L-1 subtype is thought to be a benign type.

MR colonography with limited bowel preparation compared with optical colonoscopy in patients at increased risk for colorectal cancer.

PURPOSE: To prospectively evaluate the diagnostic performance of magnetic resonance (MR) colonography by using limited bowel preparation in patients with polyps of 10 mm or larger in diameter in a population at increased risk for colorectal cancer, with optical colonoscopy as the reference standard. MATERIALS AND METHODS: The institutional review boards of all three hospitals approved the study. All patients provided written informed consent. In this multicenter study, patients undergoing colonoscopy because of a personal or family history of colorectal cancer or adenomatous polyps were included. Two blinded observers independently evaluated T1- and T2-weighted MR colonographic images obtained with limited bowel preparation (bright-lumen fecal tagging) for the presence of polyps. The limited bowel preparation consisted of a low-fiber diet, with ingestion of lactulose and an oral gadolinium-based contrast agent (with all three major meals) starting 48 hours prior to imaging. Results were verified with colonoscopic outcomes. Patient sensitivity, patient specificity, polyp sensitivity, and interobserver agreement for lesions of 10 mm or larger were calculated for both observers individually and combined. RESULTS: Two hundred patients (mean age, 58 years; 128 male patients) were included; 41 patients had coexistent symptoms. At colonoscopy, 12 patients had 22 polyps of 10 mm or larger. Per-patient sensitivity was 58% (seven of 12) for observer 1, 67% (eight of 12) for observer 2, and 75% (nine of 12) for both observers combined for polyps of 10 mm or larger. Per-patient specificity was 95% (178 of 188) for observer 1, 97% (183 of 188) for observer 2, and 93% (175 of 188) for both observers combined. Per-polyp sensitivity was 55% (12 of 22) for observer 1, 50% (11 of 22) for observer 2, and 77% (17 of 22) for both observers combined. Interobserver agreement was 93% for identification of patients with lesions of 10 mm or larger. CONCLUSION: In patients at increased risk for colorectal cancer, specificity of MR colonography by using limited bowel preparation was high, but sensitivity was modest.

MR colonography with limited bowel preparation: patient acceptance compared with that of full-preparation colonoscopy.

PURPOSE: To prospectively evaluate participants' experience and preference of magnetic resonance (MR) colonography with limited bowel preparation compared with full-preparation colonoscopy in participants at increased risk for colorectal cancer. MATERIALS AND METHODS: This study had institutional review board approval; all participants gave written informed consent. In this multicenter study, consecutive participants undergoing conventional colonoscopy because of a personal or family history of colorectal cancer or adenomatous polyps underwent MR colonography 2 weeks prior to colonoscopy. They all followed a low-fiber diet and were given lactulose and an oral contrast agent (fecal tagging with gadolinium) 2 days before colonography. Before imaging, spasmolytics were administered intravenously, and a water-gadolinium chelate mixture was administered rectally for distention of the colon. Breath-hold T1- and T2-weighted sequences were performed in the prone and supine positions. Participant experience in terms of, for example, pain and burden was determined by using a five-point scale and was evaluated with a Wilcoxon signed rank test; participant preference was determined by using a seven-point scale and was evaluated with the chi2 statistic after dichotomizing. RESULTS: Two hundred nine participants (77 women, 132 men; mean age, 58 years; range, 23-84 years) were included. One hundred forty-eight participants received sedatives (midazolam) and/or analgesics (fentanyl) during colonoscopy. Participants rated the MR colonography bowel preparation as less burdensome (P<.001) compared with the colonoscopy bowel preparation (10% and 71% of participants rated the respective examinations moderately to extremely burdensome). Participants also experienced less pain at MR colonography (P<.001) and found MR colonography less burdensome (P<.001). Immediately after both examinations, 69% of participants preferred MR colonography, 22% preferred colonoscopy, and 9% were indifferent (P<.001, 69% vs 22%). After 5 weeks, 65% preferred MR colonography and 26% preferred colonoscopy (P<.001). CONCLUSION: Participants preferred MR colonography without extensive cleansing to colonoscopy immediately after both examinations and 5 weeks later. Experience of the bowel preparation and of the procedure was rated better.

Feasibility study of computed tomography colonography using limited bowel preparation at normal and low-dose levels study.

The purpose was to evaluate low-dose CT colonography without cathartic cleansing in terms of image quality, polyp visualization and patient acceptance. Sixty-one patients scheduled for colonoscopy started a low-fiber diet, lactulose and amidotrizoic-acid for fecal tagging 2 days prior to the CT scan (standard dose, 5.8-8.2 mSv). The original raw data of 51 patients were modified and reconstructed at simulated 2.3 and 0.7 mSv levels. Two observers evaluated the standard dose scan regarding image quality and polyps. A third evaluated the presence of polyps at all three mSv levels in a blinded prospective way. All observers were blinded to the reference standard: colonoscopy. At three times patients were given questionnaires relating to their experiences and preference. Image quality was sufficient in all patients, but significantly lower in the cecum, sigmoid and rectum. The two observers correctly identified respectively 10/15 (67%) and 9/15 (60%) polyps > or =10 mm, with 5 and 8 false-positive lesions (standard dose scan). Dose reduction down to 0.7 mSv was not associated with significant changes in diagnostic value (polyps > or =10 mm). Eighty percent of patients preferred CT colonography and 13% preferred colonoscopy (P<0.001). CT colonography without cleansing is preferred to colonoscopy and shows sufficient image quality and moderate sensitivity, without impaired diagnostic value at dose-levels as low as 0.7 mSv.

Anal sphincter defects in patients with fecal incontinence: endoanal versus external phased-array MR imaging.

PURPOSE: To prospectively compare external phased-array magnetic resonance (MR) imaging with endoanal MR imaging in depicting external and internal anal sphincter defects in patients with fecal incontinence and to prospectively evaluate observer reproducibility in the detection of external and internal anal sphincter defects with both MR imaging techniques. MATERIALS AND METHODS: The medical ethics committees of both participating hospitals approved the study, and informed consent was obtained. Thirty patients (23 women, seven men; mean age, 58.7 years; range, 37-78 years) with fecal incontinence underwent MR imaging with both endoanal and external phased-array coils. MR images were evaluated by three radiologists with different levels of experience for external and internal anal sphincter defects. Measures of inter- and intraobserver agreement of both MR imaging techniques and of differences between both imaging techniques were calculated. RESULTS: Both MR imaging techniques did not significantly differ in the depiction of external (P > .99) and internal (P > .99) anal sphincter defects. The techniques corresponded in 25 (83%) of 30 patients for the depiction of external anal sphincter defects and in 28 (93%) of 30 patients for the depiction of internal anal sphincter defects. Interobserver agreement was moderate to good for endoanal MR imaging and poor to fair for external phased-array MR imaging. Intraobserver agreement ranged from fair to very good for both imaging techniques. CONCLUSION: External phased-array MR imaging is comparable to endoanal MR imaging in the depiction of clinically relevant anal sphincter defects. Because of the weak interobserver agreement, both MR imaging techniques can be recommended in the diagnostic work-up of fecal incontinence only if sufficient experience is available.

How to exclude the dilated false lumen in patients after a type B aortic dissection? The cork in the bottleneck.

PURPOSE: To report techniques for excluding the dilated false lumen associated with chronic type B aortic dissection following placement of a stent-graft in the true lumen. CASE REPORTS: Two patients underwent stent-graft implantation for a dilated false lumen after chronic aortic dissection, but the false lumen was not excluded from the circulation by this procedure. The false lumen was obliterated in one case with Greenfield filters and detachable balloons placed above a renal artery orifice that was perfused via the false lumen. This acted like "a cork in the bottleneck" to block retrograde flow into the thoracic portion of the false lumen above the blockade. In the other patient, an occluder device was used as the "cork." In both cases, a good result was obtained. The occluder device is preferred because deployment is more controllable. CONCLUSIONS: An occluder device may be used like a cork in a bottle to exclude the dilated false lumen in the thoracic aorta after a type B dissection.

Perinatal mortality: clinical value of postmortem magnetic resonance imaging compared with autopsy in routine obstetric practice.

OBJECTIVE: To compare postmortem magnetic resonance imaging (MRI) with autopsy in perinatal deaths. To determine the acceptance and feasibility of postmortem perinatal MRI. DESIGN: Cohort study. SETTING: Large teaching hospital. POPULATION: Fetuses and neonates from 16 weeks gestational age until 28 days after birth, stillbirths as well as intrapartum and neonatal deaths. METHODS: MRI was performed prior to autopsy in a consecutive cohort of perinatal deaths after full parental consent. Agreement between MRI and autopsy was calculated. The consent rate for both examinations was recorded separately, as well as the time between the perinatal death and the MRI. MAIN OUTCOME MEASURE: Full agreement between MRI and autopsy. RESULTS: Of 58 cases, 26 parents consented to both examinations (45%). Autopsy showed 18 major malformations, of which 10 were detected with MRI. The positive predictive value of MRI was 80% (4/5) and the negative predictive value was 65% (13/20). Additional consent for MRI was given in eight cases (14%). In 84%, the MRI could be performed within 48 hours. CONCLUSIONS: MRI is of value if autopsy is refused, but diagnostic accuracy is insufficient to recommend substitution of full autopsy. The acceptance rate of MRI only is better than that of autopsy.

High-resolution endovaginal MR imaging in stress urinary incontinence.

The causes of stress urinary incontinence are not completely known. Recent papers have stressed the importance of more anatomical information, which may help to elucidate the mechanism of stress urinary incontinence. The purpose of this study was to evaluate the prevalence of lesions of the urethral support mechanism and lesions (defects and scars, thinning) of levator ani muscle with endovaginal MRI in a case-control study. Forty women (median age 52 years, age range 40-65 years)--20 patients with stress urinary incontinence (cases) and 20 age-matched healthy volunteers (controls)--underwent endovaginal MRI: axial, coronal, and sagittal T2-weighted turbo spin echo. The examinations were evaluated for the presence of lesions of urethral supporting structures and levator ani and scar tissue of the levator ani. The thickness of the levator ani muscle was measured. Lesions of the urethral support system and levator ani were significantly more prevalent in cases than in controls ( p<0.01). Median levator ani thickness in patients was significantly lower than in healthy controls [2.5 mm (range 0.9-4.1 mm) vs 3.9 mm (range 1.4-7 mm)] ( p<0.01). This study indicates a relationship between stress urine incontinence and the presence of lesions of the urethral support and levator ani and levator ani thinning.