Sequential three-dimensional computed tomography analysis of implant position following total shoulder arthroplasty

Background Proper glenoid position in total shoulder arthroplasty (TSA) is important. However, traditional glenoid version (GV) measurements overestimate retroversion on radiographs (XR) and computed tomography (CT). The fulcrum axis (FA) uses palpable surface landmarks and may be useful as an intra-operative guide. Also, the FA has not yet been validated on XR or CT in an arthritic population. Methods Four observers measured FA and GV on the XR, CT and three-dimensional CT (3DCT) of 40 patients who underwent TSA at a single institution from 2009 to 2015. Reliability and accuracy of FA and GV were calculated for XR and CT, using 3DCT as the gold standard. Results The mean FA and GV were 7.768° and 18.910° on XR; 6.23° and 12.920° on CT; and 8.100° and 7.740° on 3DCT, respectively. FA and GV were significantly different for XR and CT ( p < 0.001) but not for 3DCT ( p = 0.725). The inter-rater reliability, intra-rater reliability and accuracy of FA were not significantly different from GV and were 0.929 to 0.948, 0.779 to 0.974 and 0.674 to 0.705, respectively. However, the absolute difference of FA was closer to the gold standard (3DCT) than GV for XR (0.330° versus 11.172°) and CT (1.871° versus 5.178°) ( p < 0.001). Conclusions FA showed comparable reliability and accuracy to GV. However, FA more accurately reflected the gold standard.

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Trends and impact of three-dimensional preoperative imaging for anatomic total shoulder arthroplasty

Shoulder & Elbow ◽

10.1177/1758573220908865 ◽

2020 ◽

pp. 175857322090886

Author(s):

Jourdan M Cancienne ◽

Ian J Dempsey ◽

Grant E Garrigues ◽

Brian J Cole ◽

Stephen F Brockmeier ◽

...

Keyword(s):

Computed Tomography ◽

Shoulder Arthroplasty ◽

Total Shoulder Arthroplasty ◽

Three Dimensional ◽

Preoperative Imaging ◽

Complication Rates ◽

Resonance Imaging ◽

Computed Tomography Imaging ◽

Three Dimensional Imaging ◽

Tomography Imaging

Background The goals of this study were to determine the incidence in the United States of preoperative three-dimensional imaging prior to anatomic total shoulder arthroplasty for osteoarthritis and to determine if preoperative imaging is associated with decreased complication rates. Methods Using a Medicare insurance database, we identified all patients who underwent computed tomography (n = 9380) and/or magnetic resonance imaging (n = 15,653) prior to anatomic total shoulder arthroplasty for a diagnosis of osteoarthritis from 2005 to 2014. The incidence of imaging over time was analyzed and complication rates compared between patients with imaging to matched controls. Results The incidence of preoperative three-dimensional imaging significantly increased over time, with computed tomography increasing more than magnetic resonance imaging. Compared to controls, patients with preoperative computed tomography imaging had significantly lower revision rates at two years (odds ratio 0.72 (0.64–0.82), p = 0.008). There were no other significant differences in the other complications studied. Conclusions The use of preoperative three-dimensional imaging for anatomic total shoulder arthroplasty for a diagnosis of osteoarthritis has increased dramatically, with the use of computed tomography increasing the most. Patients who underwent preoperative computed tomography imaging experienced lower revision rates at two years postoperatively compared to matched controls without such imaging. Level of evidence Level III, retrospective comparative study.

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