SS 1010 - Shoulder and wrist
Subtendinous extensor carpi ulnaris (ECU) bone marrow edema as a predictor of peripheral triangular fibrocartilage tears and ECU tendon pathology
Purpose: To determine the association between peripheral triangular fibrocartilage (TFC) tears and extensor carpi ulnaris (ECU) pathology and to evaluate subtendinous ECU bone marrow edema (BME) at the styloid process of the ulna as a diagnostic marker for TFC and ECU pathology on MRI.
Methods and Materials: The presence of TFC tears, ECU pathology (tenosynovitis, tendinosis, tears and subluxation) and subtendinous ECU BME were determined on MRI and correlated with arthroscopy. These findings were assessed in a study group of 64 patients with peripheral TFC tears and in two age- and sex-matched control groups: 64 patients with central TFC tears, and 64 patients without TFC tears (all proven with arthroscopy).
Results: Among the 64 patients without TFC tears on arthroscopy, 1.2% (8/60) had ECU pathology (all with mild ECU tendinosis, no ECU tenosynovitis, no ECU subluxation) and 0% (0/60) had subtendinous ECU BME. In the 64 patients with central TFC tears on arthroscopy, 9 (1.4%) had ECU pathology and 0% (0/60) had subtendinous ECU BME. Among the 64 patients with peripheral TFC tears, 46/60 (78%) had ECU pathology and 34/60 (70%) had subtendinous ECU BME. All 34 patients with subtendinous ECU BME (100% specificity) had both a peripheral TFC tear and ECU pathology (combined injury). 45/46 of patients with a combined injury had subtendinous BME yielding a 98% sensitivity.
Conclusion: Peripheral TFC tears are highly associated with ECU pathology. Subtendinous ECU BME on MRI indicates a combined peripheral TFC and ECU injury with 100% specificity and 98% sensitivity.
The posterior radioscaphoid angle is related to the severity of degenerative cartilage damage of the wrist in patients with scaphoid nonunion
Purpose: To determine whether the posterior radioscaphoid angle evaluated on CT-arthrography, reflecting posterior displacement of the distal pole in cases of scaphoid nonunion, is related to the cartilage damage severity of the wrist.
Methods and Materials: CT-arthrography images from 35 patients with scaphoid nonunion (cases) and from 35 patients without fractures or ligament injury (controls) were retrospectively reviewed by one experienced musculoskeletal radiologist. Cartilage morphology of the wrist including both radiocarpal and midcarpal joints was graded from 0 to 6 using a modified WORMS system. Scaphoid nonunion advanced collapse (SNAC) was graded from 0 to 3. Five carpal angles were assessed: radio-scaphoid (RS), posterior radioscaphoid (PRS), radio-lunate (RL), scapho-lunate (SL), and capito-lunate (CL). Independent sample T test was performed to test if carpal angles were able to discriminate cases from controls, as well as the different SNAC grades. Pearson correlation analysis was used to assess the correlations between carpal angles and the sum of WORMS scores (severity of the global cartilage damage).
Results: All carpal angles were able to discriminate between cases and controls (p<0.001). Only the PRS angle was able to discriminate between radiocarpal (SNAC 1 and 2) and midcarpal (SNAC 3) involvement (116.1±12.8 vs. 127.9±13.6; p=0.015). The PRS angle (0.70) better correlated with the severity of global cartilage damage than did the SL (0.64) and RS (0.46) angles (p <0.0001).
Conclusion: The PRS angle was able to discriminate between radiocarpal and midcarpal involvement (SNAC) and demonstrated better correlation with global cartilage damage severity in patients with scaphoid nonunion.
Purpose: To study the correlation between quantitative analysis of diffusion tensor imaging (DTI) of median nerve (MN) and CTS severity determined by delta cross-sectional area measurement (Δ-CSA).
Methods and Materials: Thirty-seven CTS patients (25 females and 12 males) [mean age 58.11± Std] were examined using a 3T MR scanner (Skyra, Erlangen, Germany). The examination protocol included diffusion tensor imaging (DTI) in addition to routine sequences (coronal T1 VIBE, axial T1 and T2 TIRM) for anatomical correlation. All patients underwent ultrasound examination using 5-18 MHz (HI Vision Preirus, Hitachi Aloka Medical, Ltd, Tokyo) for diagnosis of CTS. Δ-CSA measurement represented the difference in CSA between MN at distal forearm and carpal tunnel. Patients were divided into three groups based on Δ-CSA (mild, moderate and severe). Mean apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were correlated to Δ-CSA.
Results: Patients were classified as follows (mild = 8, moderate = 9 and severe = 25). Mean ADC and FA values were 1.482x10-3 and 0.541x10-3, respectively. A significant mild to moderate correlation was shown between FA and Δ-CSA (r=0.311, P=0.044), however, no correlation between ADC and Δ-CSA. Mean FA values were 602.4, 560.2 and 523 for mild, moderate and severe groups, respectively, with a significant difference between severe and mild groups (P=0.027).
Conclusion: Quantitative analysis of diffusion using ADC and FA proved feasible with a mild to moderate correlation between FA and severity grade of CTS determined by Δ-CSA, with a significant difference between severe and mild groups.
Comparison of T2 BLADE PD and isotropic three-dimensional fast spin echo cube (3D T2 SPACE) sequences with conventional protocols in wrist lesions using 3T MRI
Purpose: Magnetic Resonance Imaging (MRI) of wrist is a useful diagnostic method for different wrist structures, however the efficacy could be optimized. In this study we compared new protocols of 3D T2SPACE, PD BLADE and T2 BLADE with the conventional protocols, including T2 FSE, PD FSE and T1 FSE for wrist imaging.
Methods and Materials: Twenty patients (12 men) with history of wrist trauma or suspected wrist lesions were enrolled. All protocols were carried out on all patients; then quality of each protocols was assessed by two musculoskeletal radiologists and one hand surgeon.In addition, signal to noise ratio (SNR) and contrast to noise ratio (CNR) in specific regions of interests (ROIs) [including TFCC,cartilage and bone] were measured. At the end, all of qualitative and quantitative assessments were compared between protocols.
Results: SNR of cartilage, TFCC on 3D T2SPACE and T1 FSE was better than other sequences (P<0.001). SNR of bone on PD BLADE was significantly higher than that of conventional protocols (P<0.001). PD BLADE images showed significantly higher bone-cartilage CNR and bone-TFCC CNR (P<0.001 to P<0.001). CNR of cartilage-TFCC on T1 FSE was better than other sequences, but no statistically significant difference was seen. Qualitative assessment showed better wrist imaging in SPACE and BLADE protocols in comparison to conventional sequences (P<0.001).
Conclusion: PD BLADE, 3D T2SPACE and T2 BLADE MRI protocols were superior compared to conventional sequences in wrist imaging. High-SNR and CNR in SPACE and BLADE MR sequences could be a promising method to diagnose wrist lesion.
Purpose: Indoor rock climbing is gaining increasing popularity. Thus the incidence of climbing related injuries is rising. About 40% of these are to the fingers. Out of the entirety of injuries of the upper extremity, we demonstrate lesions of the finger which were evident in a network for rock climbing medicine.
Methods and Materials: Between 05/2012 and 06/2016, a total of 227 finger injuries were seen. Following clinical examination, MR-imaging was performed. In case of a lesion to the flexor-tendon-pulley-system, a 4-step grading system was used.
Results: MR-imaging disclosed characteristic dilatation and thickening of the interdigital joint capsule in almost all cases. Stress fractures were evident in 19 cases (adult fracture: 1, physeal fracture: 18). Capsular lesions were seen in 6 cases (capsular rupture: 4, plantar plate rupture: 2). Lesions of the flexor tendon were found in 39 cases. 1 lumbrical shift syndrome and 1 calcified stenosis of the A2-annular pulley were disclosed. Lesions of the flexor-tendon-pulley-system were seen in 162 cases (Gl: n=22, GII: n=103, GIII: n=46, GIV: n=1).
Conclusion: Knowledge of the anatomy and the biomechanics is important to differentiate physiologic chances from true injuries. MR-imaging is important for classification of GII lesions of the flexor-tendon-pulley-system, which are the most common and of high sport physiologic importance. Furthermore, MR-imaging allows distinguishing complex lesions, which may require surgical repair.
Impact of delimitation on the healing of rotator cuff injury after a tension band arthroscopic repair
Purpose: Arthroscopic repair of transfixing rotator cuff lesions using the « tension band » technique gives good results. The impact of tendon delamination is less known than the degree of tendon retraction on the anatomical result. The aim of our study was to assess the impact of delamination on tendon healing after arthroscopic cuff repair made with the « tension band » technique.
Methods and Materials: 117 patients with a transfixing lesion of the rotator cuff operated thanks to the « tension band » technique, over a 5-year period, were clinically and anatomically evaluated. The delaminated or not status of the rotator cuff injury and the stage of retraction was set intraoperatively. All patients had a 6 months minimum follow-up. Tendon healing was evaluated by ultrasound and functional outcome using the adjusted Constant score.
Results: 80 patients had a non-delaminated rotator cuff injury and 37 a delaminated one. The healing rate was 78% and 57% respectively (p = 0.0287). Patients were comparable preoperatively in terms of age, sex, BMI, Subjective Shoulder Value, strength and adjusted Constant score. There were no significant differences in the subgroup analysis for the stage 1(77% versus 75%), and stage 2 (75% versus 60%) retracted lésions. There was a significant difference for the stage 3 retracted lesions (83% versus 45%; p <0.05).
Conclusion: Delamination appears as a key factor in the healing of arthroscopic repair of rotator cuff lesions. Ultrasound was a useful tool to assess the anatomical result of the surgery.
Combined quantitative MR imaging assessment of the rotator cuff integrity at 3.0T by multi-echo Dixon-based fat quantification and diffusion tensor imaging
Purpose: To establish quantitatively normative values of fractional fat content (FF%) and diffusion tensor imaging (DTI) parameters (fractional anisotropy [FA] and apparent diffusion coefficient [ADC]) of normal rotator cuff (RC)-muscles.
Methods and Materials: 40 patients underwent standard direct MR arthrography of the shoulder including 3D multi-echo Dixon and 3D echo-planar DTI sequences (15 gradient encoding directions, b-value 600 s/mm2) at equal spatial resolution. RC-muscles and tendons were qualitatively assessed. Goutallier gradings >1 and tendon tears were excluded from further analysis. FF%, FA and ADC were evaluated quantitatively by region-of-interest (ROI) measurements at Y-position of the scapula by two independent radiologists. Intraclass correlation coefficients (ICC) were calculated. Pearson correlation, Student’s t-test, Chi-Square test and one-way ANOVA testing were performed to correlate measurements with age and gender and to compare different RC muscles and two Goutallier groups (0 and 1).
Results: Interreader agreements for quantitative measurements were perfect (ICC: 0.90-0.99). Goutallier 0 muscles showed significant positive correlations of FF% and FA with age (R=0.269, p<0.01 and 0.206, p<0.05) as well as FF% with FA (R=0.351, p<0.001). Significant differences were seen among different RC muscles in Goutallier group 0 for FF% and ADC (p=0.011 and p=0.001) but not in Goutallier group 1 (p>0.05). ADC is significantly different between Goutallier groups for all RC muscles (p<0.05).
Conclusion: Quantitative MR assessment of RC-muscle integrity delivers high interreader agreement. In normal RC muscles FF% and FA increase significantly with age. ADC allows best to differentiate between Goutallier group 0 and 1 in all RC-muscles.
Preoperative MR imaging characteristics of full-thickness rotator cuff tendon tears do not correlate with changes in clinical outcome scores following repair
Purpose: The purpose of this study was to evaluate whether preoperative MR imaging features of full-thickness rotator cuff tears correlated with changes in subjective and functional outcomes following surgical repair.
Methods and Materials: This retrospective study included 208 patients who underwent conventional shoulder MRI examination within 12 months of full-thickness rotator cuff tendon tear repair and performed preoperative and 12 month postoperative clinical outcome scoring. Clinical outcome scoring systems utilised were SF-12, QuickDASH, and SANE. A musculoskeletal radiologist evaluated all MRI for tear size, tendon retraction, tendinosis, atrophy, fatty infiltration, glenohumeral cartilage loss, biceps tendinosis or tear, and labral tear. Pearson correlation coefficients, Student's t-test, and one-way ANOVA was used to analyse for statistically significant correlation between clinical outcome score changes and MR imaging features.
Results: Overall, there were statistically significant postoperative improvements in SANE scores, QuickDASH scores, and bodily pain, physical functioning, and physical health composite scale scores from the SF-12 (p<0.01). Female patients demonstrated greater improvement in QuickDASH scores than did male patients (p<0.05). Average size of the tears measured 2.6 cm in anteroposterior dimension with an average of 2.3 cm of retraction. There was no statistically significant correlation between any of the measured MR imaging characteristics and postoperative changes in SF-12, QuickDASH, or SANE clinical outcome scores.
Conclusion: MR imaging features of full-thickness rotator cuff tendon tears do not correlate with changes in clinical outcome scores following repair of full thickness rotator cuff tears.
Purpose: The purpose of our study is to investigate the association of MRI findings of adhesive capsulitis (AC) with the clinical examination.
Methods and Materials: Following IRB approval, 256 subjects with untreated, unilateral idiopathic AC for 3 to 12 months were enrolled in a clinical trial for treatment and all received shoulder MRI. Clinical evaluation included calculation of American Shoulder and Elbow Surgeons Shoulder function and pain scores, and multi-directional shoulder range of motion (ROM). Two radiologists blindly reviewed the studies for AC MR Characteristics. The most prevalent findings were graded using a 4-point Likert scale (normal, mild, moderate, and severe), including coracohumeral ligament thickening, capsular thickening at axillary pouch, edema within axillary pouch, and synovitis along superior border of subscapularis tendon, and overall assessment of AC severity.One-way Analysis-of-Variance models were used with significance level set at 0.05.
Results: Multi-directional ROM and clinical exam scores were grouped, thus, our p-values are reported as a range. All MRI findings showed some significant correlation. Edema within axillary pouch was associated with clinical exam scores (p 0.004-0.035), active ROM (p <0.001-0.021), and passive ROM (p <0.001-0.007). Overall assessment of AC severity was associated with the clinical exam scores (p <0.001-0.005), active ROM (p <0.001-0.041), and passive ROM (p <0.001-0.028). These two findings demonstrated most significant association.
Conclusion: The strong association between MRI characteristics and clinical exam scores in patients with clinically confirmed AC suggests MRI can serve as a tool for grading severity and therefore guide clinical treatment.
Glenoid surface measuraments by means of 3D MRI: comparison between healthy volunteers and first time dislocators
Purpose: To identify any differences in glenoid area measuraments in healthy volunteers, in comparison to post-traumatic and non-traumatic anterior shoulder dislocators.
Methods and Materials: IRB approval was obtained for this prospective study and written informed consent was obtained from patients enrolled. A total of 124 patients (84 males, 40 females; range 14-62 years) studied with MRI including an isotropic 3D sequence were evaluated. By using the best-fit circle method, glenoid surface area was measured in the following patients subgroups: GR1=35 healthy volunteers; GR2=54 post-traumatic dislocators; GR3=35 non-traumatic dislocators. Two measurements were performed by two experienced radiologists, independently, on a dedicated workstation with at least 1 month gap. Differences between subgroups were calculated by using Student t test and Pearson correlation. A value of p<0.05 was considered statistically significant. Intra and Inter-reader variation was determined with the interclass correlation coefficient.
Results: As regards glenoid surface area, differences were not significant between GR1 (mean 484, range 355-562 square millimiters) and GR2 (mean 491, range 364-586 square millimiters); conversely a significant difference (p=0.025) was determined between GR1 and GR3 (mean and range values of 441 and 323-537 square millimiters, respectively) and between GR2 and GR3 (p=0.02). The difference was not significant when comparing GR2 to GR3 (mean 6.2%, range 1-27%). There was excellent intra- and inter-reader correlation (R=0.94 and R=0.98 respectively).
Conclusion: Glenoid area of patients undergoing non-traumatic shoulder dislocation is significantly smaller if compared to a control-group of healthy volunteers and to patients undergoing post-traumatic shoulder dislocation.
Added value of combined acromiohumeral distance and critical shoulder angle measurements on conventional radiographs for the prediction of rotator cuff pathology
Purpose: To investigate the role of acromiohumeral distance (AHD) and critical shoulder angle (CSA) measurements from conventional radiographs (CR) in isolation and combined as predictors of transmural rotator cuff tendon tears (RCT) and critical fatty degeneration (CFD).
Methods and Materials: In this retrospective study in 127 AHD and CSA were measured on CR. MR Arthrograms served as reference standard and were screened for RCT and CFD (Goutallier stages ≥2). Statistical analysis for inter-reader agreement, Spearman’s rank correlation, linear stepwise regression and diagnostic performance at different cut-off values for AHD and CSA both isolated and combined were performed.
Results: In 90 subjects (17 females, mean age 36.1±14.1) no RCT were found on MR imaging and served as control group. In 37 patients (13 females, mean age 58.7±13.2) at least one RCT was found. Inter-reader agreements rated between к=0.42-0.82 for categorical and 0.91-0.96 for continuous variables. No significant correlation of AHD and CSA with either age or gender was seen (p=0.28 and p=0.74, respectively). Case group had significantly smaller mean AHD (8.7±3.2 vs 10.8±2.2 mm; p<0.001) and larger mean CSA (36.5±4.5° vs 33.1± 4.0°; p<0.001). Combination of AHD-CSA-measurements increased specificity and positive predictive value (PPV) for prediction of RCT and CFD.
Conclusion: RCT and CFD correlate with smaller AHD and larger CSA. Combination of AHD and CSA measurements leads to increased specificity and PPV for detection of RCT or CFD. Goutallier stage of the infraspinate muscle is associated with small AHD and large CSA.