Abstract:

Objective　To verify the accuracy of humeral head retroversion angle with  two different methods commonly used in clinical practice and assess the value in the shoulder arthroplasty.　Methods　20 dry humerus specimens (bones with closed growth plates and no signs of degenerative or post-traumatic alterations. No information about sex or age) were scanned with 64 slice spiral CT, using two methods-the traditional two-dimensional CT measurement and a simple two-dimensional CT measurement, to measure the humeral head retroversion angle; then use the anatomical measurement to obtain the standard data; At last, the three groups data on humeral head retroversion angle were statistically analyzed.　Results　The angle of retroversion was （32.1±13.9）° using  traditional two-dimensional CT method, (30.2±14.3)° using the simple two-dimensional CT method, and (32.1±13.6)° using anatomical dissection. There was no statistical difference between groups by statistics (P>0.05).　Conclusion　Both methods can assess the humeral head retroversion angle very accurately, but the new two-dimensional CT method is relatively simpler, faster, more intuitive and practical. The Humeral head retroversion angle has great individual differences, and it is of great significance to accurately assess its value before the individually surgery.

Key words: Humeral head retroversion angle, Measurement, Accuracy, Shoulder arthroplasty