Ehlers-Danlos Syndrome (EDS) is a hereditary disorder of the connective tissue, which has been classified into numerous subtypes over the years. EDS is generally characterized by hyperextensible skin, hypermobile joints, and tissue fragility. According to the 2017 International Classification of EDS, 13 subtypes of EDS have been recognized. The majority of genes involved in EDS are either collagen-encoding genes or genes encoding collagen-modifying enzymes. Orthopedic surgeons most commonly encounter patients with the hypermobile type EDS (hEDS), who present with signs and symptoms of hypermobility and/or instability in one or more joints. Patients with joint hypermobility syndrome (JHS) might also present with similar symptomatology. This article will focus on the surgical management of patients with knee or shoulder abnormalities related to hEDS/JHS.

Background: Recent literature suggests that three-dimensional magnetic resonance imaging (3D MRI) can replace 3D computed tomography (3D CT) when evaluating glenoid bone loss in patients with shoulder instability. We aimed to examine if 2D MRI in conjunction with a validated predictive formula for assessment of glenoid height is equivalent to the gold standard 3D CT scans for patients with recurrent glenohumeral instability. Methods: Patients with recurrent shoulder instability and available imaging were retrospectively reviewed. Glenoid height on 3D CT and 2D MRI was measured by two blinded raters. Difference and equivalence testing were performed using a paired t-test and two one-sided tests, respectively. The interclass correlation coefficient (ICC) was used to test for interrater reliability, and percent agreement between the measurements of one reviewer was used to assess intrarater reliability. Results: Using an equivalence margin of 1 mm, 3D CT and 2D MRI were found to be different (p = 0.123). The mean glenoid height was significantly different when measured on 2D MRI (39.09 ± 2.93 mm) compared to 3D CT (38.71 ± 2.89 mm) (p = 0.032). The mean glenoid width was significantly different between 3D CT (30.13 ± 2.43 mm) and 2D MRI (27.45 ± 1.72 mm) (p < 0.001). The 3D CT measurements had better interrater agreement (ICC, 0.91) than 2D MRI measurements (ICC, 0.8). intrarater agreement was also higher on CT. Conclusions Measurements of glenoid height using 3D CT and 2D MRI with subsequent calculation of the glenoid width using a validated methodology were not equivalent, and 3D CT was superior. Based on the validated methods for the measurement of glenoid bone loss on advanced imaging studies, 3D CT study must be preferred over 2D MRI in order to estimate the amount of glenoid bone loss in candidates for shoulder stabilization surgery and to assist in surgical decision-making.

Background: Recent literature suggests that three-dimensional magnetic resonance imaging (3D MRI) can replace 3D computed tomography (3D CT) when evaluating glenoid bone loss in patients with shoulder instability. We aimed to examine if 2D MRI in conjunction with a validated predictive formula for assessment of glenoid height is equivalent to the gold standard 3D CT scans for patients with recurrent glenohumeral instability. Methods: Patients with recurrent shoulder instability and available imaging were retrospectively reviewed. Glenoid height on 3D CT and 2D MRI was measured by two blinded raters. Difference and equivalence testing were performed using a paired t-test and two one-sided tests, respectively. The interclass correlation coefficient (ICC) was used to test for interrater reliability, and percent agreement between the measurements of one reviewer was used to assess intrarater reliability. Results: Using an equivalence margin of 1 mm, 3D CT and 2D MRI were found to be different (p = 0.123). The mean glenoid height was significantly different when measured on 2D MRI (39.09 ± 2.93 mm) compared to 3D CT (38.71 ± 2.89 mm) (p = 0.032). The mean glenoid width was significantly different between 3D CT (30.13 ± 2.43 mm) and 2D MRI (27.45 ± 1.72 mm) (p < 0.001). The 3D CT measurements had better interrater agreement (ICC, 0.91) than 2D MRI measurements (ICC, 0.8). intrarater agreement was also higher on CT. Conclusions Measurements of glenoid height using 3D CT and 2D MRI with subsequent calculation of the glenoid width using a validated methodology were not equivalent, and 3D CT was superior. Based on the validated methods for the measurement of glenoid bone loss on advanced imaging studies, 3D CT study must be preferred over 2D MRI in order to estimate the amount of glenoid bone loss in candidates for shoulder stabilization surgery and to assist in surgical decision-making.

PURPOSE: To identify potential differences in interportal capsulotomy size and cross-sectional area (CSA) using the anterolateral portal (ALP) and either the: (i) standard anterior portal (SAP) or (ii) modified anterior portal (MAP). MATERIALS AND METHODS: Ten cadaveric hemi pelvis specimens were included. A standard arthroscopic ALP was created. Hips were randomized to SAP (n=5) or MAP (n=5) groups. The spinal needle was placed at the center of the anterior triangle or directly adjacent to the ALP in the SAP and MAP groups, respectively. A capsulotomy was created by inserting the knife through the SAP or MAP. The length and width of each capsulotomy was measured using digital calipers under direct visualization. The CSA and length of the capsulotomy as a percentage of total iliofemoral ligament (IFL) side-to-side width were calculated. RESULTS: There were no differences in mean cadaveric age, weight or IFL dimensions between the groups. Capsulotomy CSA was significantly larger in the SAP group compared with the MAP group (SAP 2.16±0.64 cm2 vs. MAP 0.65±0.17 cm2, P=0.008). Capsulotomy length as a percentage of total IFL width was significantly longer in the SAP group compared with the MAP group (SAP 74.2±14.1% vs. MAP 32.4±3.7%, P=0.008). CONCLUSION The CSA of the capsulotomy and the percentage of the total IFL width disrupted are significantly smaller when the interportal capsulotomy is performed between the ALP and MAP portals, compared to the one created between the ALP and SAP. Surgeons should be aware of this fact when performing hip arthroscopy.