Hugues Demezon

Normative 3D acetabular orientation measurements by the low-dose EOS imaging system in 102 asymptomatic subjects in standing position: Analyses by side, gender, pelvic incidence and reproducibility

BACKGROUND Three-dimensional (3D) acetabular orientation is a fundamental topic in orthopedic surgery. Computed tomography (CT) allows 3D measurement of native acetabular orientation, but with a substantial radiation dose. The EOS imaging system was developed to perform this kind of evaluation, but has not been validated in this indication with specific attention to the acetabulum. We therefore performed a prospective study using EOS to assess: (1) the reproducibility of the 3D acetabulum orientation measures; (2) normative asymptomatic acetabular morphology in standing position, according to side and gender; and (3) the relationship between acetabular anteversion and pelvic incidence. HYPOTHESIS The low-dose EOS imaging system is a reproducible method for measuring 3D acetabular orientation in standing position. PATIENTS AND METHODS In a previous prospective study of spine sagittal balance, 165 asymptomatic volunteers were examined on whole-body EOS biplanar X-ray; 102 had appropriate images for pelvic and acetabular analysis, with an equal sex-ratio (53 female, 49 male). These EOS images were reviewed using sterEOS 3D software, allowing automatic measurement of acetabular parameters (anteversion and inclination) and pelvic parameters (pelvic incidence, pelvic tilt and sacral slope) in an anatomical (anterior pelvic plane: APP) and a functional reference plane (patient vertical plane: PVP). RESULTS Both intra- and inter-observer analysis showed good agreement (ICC>0.90); Bland-Altman plot distributions were good. Acetabular anatomical anteversion and inclination relative to APP (AAAPP and AIAPP, respectively) were significantly greater in women than in men, with no effect of side (right AAA: women 21.3°±3.4° vs. men 16.1°±3.3° (P<0001); right AIAPP: women 55.3°±3.7° vs. men 52.5°±3.0° (P<0001); left AAAPP: women 20.9°±3.5° vs. men 15.6°±4.0° (P<0001); left AIAPP: women 54.6°±3.5° vs. men 52.7°±2.8° (P=0003)). The same differences between men and women were observed when measurements were related to PVP. Pelvic incidence subgroup (<44°; 44-62°; >62°) correlated significantly with functional acetabular orientation in standing position: PVP functional anteversion decreased by 5° relative to APP anteversion with incidence <44°, was equal to APP with incidence 44-62°, and or was greater by 4° relative to APP with incidence >62°. DISCUSSION The use of a 3D sterEOS software prototype version for 3D reconstruction of the native acetabulum from standard EOS X-ray was shown to be a reliable and reproducible method. This innovative method enabled the reference values of 3D acetabular orientation in standing position to be measured for the first time. The results reinforced the concept of hip-spine relationships, and involved very low radiation dose. LEVEL OF EVIDENCE IV prospective study without control group.

Surgical repair of large-to-massive rotator cuff tears seems to be a better option than patch augmentation or débridement and biceps tenotomy: a prospective comparative study

BACKGROUND This prospective study compared the outcomes after 3 different treatments for large and massive rotator cuff tears. METHODS Patients with a diagnosis of large-to-massive rotator cuff tears were prospectively included. Patients were allocated in 3 groups: (1) arthroscopic complete repair (repair group), (2) open repair and xenograft patch augmentation (patch group), and (3) arthroscopic débridement and tenotomy of the long head of the biceps (débridement group). Patients were evaluated preoperatively and postoperatively at 3, 6, 12 and 24 months. The primary outcome measure was the Constant-Murley score. RESULTS The study included 32 consecutive patients. The mean improvement in the Constant-Murley score was +29.1 for the repair group (P < .01), +32.2 for the patch group (P < .01), and +20.1 for the débridement group (P < .01) at the final follow-up examination. No differences were found between the repair and patch groups, but the difference became significant between the débridement group and the patch group (P < .001) and also between the débridement group and the repair group (P < .002) at 12 months and the final follow-up. Moreover, 5 complications occurred in 11 patients in the patch group, whereas there was only 1 complication in the repair group and no complications in the débridement group. CONCLUSION The use of porcine dermis patches to augment repairs of massive and irreparable rotator cuff tears is not recommended because there is no benefit compared with repair without augmentation and patches result in more complications.