A Retrospective Study of Moore and Thompson Hemiarthroplasty

In a retrospective review of 580 patients with 599 hemiarthroplasties of the hip, 454 operations (75.8%) were carried out as primary procedures for fresh intracapsular fractures, and 145 operations (24.2%) were performed as salvage procedures. The three-month mortality rate was 5.0%, and the dislocation rate was 5.3%. The early results were assessed by roentgenograms alone; head size, neck length, stem-shaft angle, and calcar seating were measured on preoperative and postoperative films. Anteversion and retroversion could not be accurately assessed. Using an arbitrary rating system, the results were graded as excellent on the basis of four anatomical criteria: good, on the basis of three; fair, of two; and poor, on only one or none. Only 173 prostheses (26.3%) were graded as excellent and 103 (27.3%) as good. At least 70 (25.3%) were just fair, and 31 (11.2%) were poor. Inappropriate neck length was present in 55.0% of the dislocated prostheses, incorrect head size in 25.0%, varus of the prosthesis in 20.0%, and poor calcar seating in 25.0%. Thus, technical errors account for a significant number of imperfect hemiarthroplasties of the hip. Careful attention to detail should decrease the incidence of errors and improve end-results.