Elbow radiographic anatomy of normal adults and Coonrad-Morrey total elbow arthroplasty / 中华骨科杂志

ABSTRACT

Objective To investigate the alignment of the elbow after Coonrad-Morrey (CM) total elbow arthroplasty (TEA),and to establish normal radiographic parameters correlated with prosthesis design in Chinese adults,as well as to detect whether CM prosthesis fits for Chinese.Methods Forty-two healthy volunteers were recruited and underwent radiographs of bilateral elbows in a standardized anterior-posterior (AP) fashion.Furthermore,99 AP radiographs of normal elbows and 54 AP radiographs of elbows after CM TEA were both collected from Picture Archiving and Communication System.The following radiographic parameters were measuredhumerus-elbow-wrist (HEW) angle,the angle between the axis of humerus medullary cavity and the hinge axis of elbow (H-H angle),the angle between the axis of middle ulna medullary cavity and the hinge axis of elbow (MU-H angle),the angle between the axis of proximal ulna medullary cavity and the hinge axis of elbow (PU-H angle),the horizontal distance between the axis of humerus medullary cavity and the axis of proximal ulna medullary cavity (medullary translation).The differences in above parameters between normal elbows and elbows after CM TEA were compared.For normal elbows,the radiographic differences between male and female and that between right and left were analyzed,as well as the correlation with height.Results HEW angle (2.71°±8.08°) and medullary translation (1.79±3.49 mm) in patients after CM TEA were significantly less than that in normal (11.30°±7.21°,5.25±2.55 mm respectively),while H-H angle (89.92°±3.64°),MU-H angle (93.34°±6.30°) and PU-H angle (78.87°±4.79°) were significantly larger than that in normal (87.59°±5.62°,89.23°±5.66°,76.22°±4.69° respectively).The right HH angle of female was significantly larger than that in male.There were no significant difference in other parameters between male and female,and between right and left.All of the correlations between these parameters and height were not significant.Conclusion Elbow valgus decreases and forearm translates laterally after CM TEA in Chinese patients.Currently,the CM prosthesis can theoretically cause decreasing elbow valgns and lateral translation of forearm.