The reverse shoulder arthroplasty angle: a new measurement of glenoid inclination for reverse shoulder arthroplasty.

BACKGROUND: Avoiding superior inclination of the glenoid component in reverse shoulder arthroplasty (RSA) is crucial. We hypothesized that superior inclination was underestimated in RSA. Our purpose was to describe and assess a new measurement of inclination for the inferior portion of the glenoid (where the baseplate rests). METHODS: The study included 47 shoulders with rotator cuff tear arthropathy (mean age, 76 years). The reverse shoulder arthroplasty angle (RSA angle), defined as the angle between the inferior part of the glenoid fossa and the perpendicular to the floor of the supraspinatus, was compared with the global glenoid inclination (ß angle or total shoulder arthroplasty [TSA] angle). Measurements were made on plain anteroposterior radiographs and reformatted 2-dimensional (2D) computed tomography (CT) scans by 3 independent observers and compared with 3-dimensional (3D) software (Glenosys) measurements. RESULTS: The mean RSA angle was 25° ± 8° on plain radiographs, 20° ± 6° on reformatted 2D CT scans, and 21° ± 5° via 3D reconstruction software. The mean TSA angle was on average 10° ± 5° lower than the mean RSA angle (P < .001); this difference was observed regardless of the method of measurement (radiographs, 2D CT, or 3D CT) and type of glenoid erosion according to Favard. In Favard type E1 glenoids with central concentric erosion, the difference between the 2 angles was 12° ± 4° (P < .001). CONCLUSION: The same angle cannot be used to measure glenoid inclination in anatomic and reverse prostheses. The TSA (or ß) angle underestimates the superior orientation of the reverse baseplate in RSA. The RSA angle (20° ± 5°) needs to be corrected to achieve neutral inclination of the baseplate (RSA angle = 0°). Surgeons should be aware that E1 glenoids (with central erosion) are at risk for baseplate superior tilt if the RSA angle is not corrected.

Tibial slope in total ankle arthroplasty: Anterior or lateral approach.

BACKGROUND: A new total ankle arthroplasty (TAA) system performed through a lateral approach provides direct visualization of the centre of rotation, allowing for accurate reconstruction of the joint alignment and less bone resection. Radiographic references are needed to describe deformities and plan the surgical procedures. The tibial slope is an important factor when treating malalignment. The aim of this study is to show if there is any difference regarding the post-operative tibial slope (ß angle) measurement comparing a fixed-bearing TAA through a lateral approach and a mobile-bearing TAA through an anterior approach. METHODS: The study included 217 ankles. Between May 2011 and April 2015, 77 patients underwent a TAA with a mobile-bearing implant through an anterior approach and 45 with a fixed-bearing implant through a lateral approach: in these patients the ß angle was measured 2 and 12 months postoperatively. 95 subjects with unilateral post-traumatic ankle arthritis composed the control group: in these patients we measured the anterior distal tibial angle (ADTA) of the controlateral, non arthritic tibiotalar joint. RESULTS: In the mobile-bearing group, the mean ß angle at 2 and 12 months postoperatively was 86.4±3.1 and 86.8±3.1 (p-value=0.12). In the fixed-bearing group, the mean ß angle at 2 and 12 months postoperatively was 83.1±5.4 and 83.9±6.5 (p-value=0.26). A statistically significant difference was found between the ß angle of the two groups. In the control group the mean ADTA was 84.9±2.5. A non-statistically significant difference was observed only between ß angle of the fixed-bearing group and the ADTA of the control group. CONCLUSIONS: Regarding the tibial slope, fixed-bearing TAA through a lateral approach showed a more anatomic placement. In contrast, ß angle in mobile-bearing group appeared more reproducible than fixed-bearing group.

Transperineal ultrasonography in stress urinary incontinence: The significance of urethral rotation angles.

OBJECTIVE: To assess, using transperineal ultrasonography (TPUS), the numerical value of the rotation of the bladder neck [represented by the difference in the anterior (α angle) and posterior urethral angles (ß angle)] at rest and straining, in continent women and women with stress urinary incontinence (SUI), to ascertain if there are significant differences in the angles of rotation (Rα and Rß) between the groups. PATIENTS SUBJECTS AND METHODS: In all, 30 women with SUI (SUI group) and 30 continent women (control group) were included. TPUS was performed at rest and straining (Valsalva manoeuver), and the threshold value for the urethral angles (α and ß angles) for each group were estimated. The degree of rotation for each angle was calculated and was considered as the angle of rotation. RESULTS: Both the α and ß angles were significantly different between the groups at rest and straining, and there was a significant difference in the mean increment in the value of each angle. Higher values of increment (higher rotation angles) were reported in the SUI group for both the α and ß angles compared with those of the control group [mean (SD) Rα SUI group 19.43 (12.76) vs controls 10.53 (2.98) °; Rß SUI group 28.30 (12.96) vs controls 16.33 (10.8) °; P < 0.001]. CONCLUSION: Urethral rotation angles may assist in the assessment and diagnosis of patients with SUI, which may in turn reduce the need for more sophisticated urodynamic studies.

Comparing the range of µ and ß angles in 6-17-year-old children of Isfahan with normal occlusion.

BACKGROUND: Linear and angular measurements such as A point, nasion, B point (ANB) angle and Wits appraisal index are not accurate enough to evaluate sagittal relationship of the jaws. The aim of this study was to evaluate and compare the range of µ and ß angles in 6-17-year-old children of Isfahan, having normal occlusion. MATERIALS AND METHODS: This was an analytical descriptive study. For this study, 235 cephalometric radiographs of patients who didn't receive orthodontics treatments and based on 13 indexes had normal occlusion, were selected. After tracing of cephalograms, ANB angle, Wits appraisal index, µ angle (resulted from the intersection of AB line and perpendicular line from point A to mandibular plane) and ß angle (resulted from the intersection of AB line and perpendicular line from point A on CB line) were measured. Data was analyzed by t-test, ANOVA and Pierson-Spearman correlation coefficient (P < 0.05). RESULTS: Mean value of µ and ß angles were 17.34 ± 3.47 and 31.7 ± 3.31 and ranged from 8-27 to 21.5-39 respectively. According to t-test, there was a significant difference between two sex groups for µ angle (P = 0.02); however, it was not significant for ß angle. According to Spearman correlation coefficient, there was no significant difference between age and µ angle; however, ß angle was directly and significantly related to age (r = 0.435). There was significant and reverse relationship between µ and ß angles with ANB angle and Wits appraisal index. CONCLUSION: µ and ß angles are reliable and can be used to evaluate the anterior-posterior relationship of the jaws.