Unipolar or Bipolar Prosthesis for Displaced Intracapsular Hip Fracture in Octogenarians

Abstract

We performed a randomised prospective trial to compare a cemented unipolar prosthesis (Thompson) with a cemented bipolar prosthesis (Monk) in the treatment of displaced intracapsular fractures of the hip in patients over 80 years of age. Patients with a mental test score of less than 5/13 were excluded but the mortality was still about 30% at one year in both groups. We therefore feel that subjective criteria such as the level of pain and the return to the preinjury state are of paramount importance.Two years after operation there was no statistical difference between the rate of complications in the two groups. After adjusting for confounding factors such as differences in the level of function before injury between the groups, the degree of return to the preinjury state was significantly greater (p = 0.04) when using the unipolar prosthesis, which is one-quarter of the price of the bipolar.We cannot therefore justify the use of an expensive bipolar prosthesis in patients over 80 years of age.

High Dislocation Cumulative Risk in THA versus Hemiarthroplasty for Fractures

“…This conforms to the literature: acetabular erosion has been considered to occur with rates ranging from 2% [5] to 36% [25] with a unipolar design and from 0% [5] to 26 % [24] for a bipolar design. Furthermore when acetabular erosion was graded, Baker et al [2] reported a 66% rate of acetabular erosion.…”

Bipolar Versus Fixed-Head Hip Arthroplasty for Femoral Neck Fractures in Elderly Patients

“…Our results disagree with the randomized prospective study of Van Thiel et al [21] and Calder et al [18] , who did not find any differences between the Moore unipolar and bipolar prostheses concerning acetabular erosion. Our results are consistent with Yamagata et al [22] and D'Arcy and Devas [23] who found more erosion with unipolar prosthesis, and Wetherell and Hinves [14] who reported a rate of erosion of 5.6% with the bipolar implant compared with 11% for the cemented Thompson prosthesis.…”

“…Drinker and Murray [17] in a retrospective series compared the bipolar prosthesis with the Thompson prosthesis and could not show a significant advantage to the bipolar prosthesis. Calder et al [18] in his study concluded that there is no justification for the use of the expensive bipolar hip prosthesis in femoral neck fracture. On the other hand, La Belle et al [19] reported that bipolar prosthesis resulted in less pain and decreased protrusio in comparison with the conventional fixed-head prosthesis.…”

“…Calder [18] reported that movement within the prosthesis may also reduce the pain caused by the prosthesis moving against the acetabulum. In our study, the bipolar group had a better range of motion and 90% of the patients had no limping and 10% had a slight limping, while in the fixed-head group, 22% of the patients had a moderate to severe limping.…”

Different Types of Hip Endoprostheses after Osteoporotic Femoral Neck Fracture; Functional Results?

“…However, opinions about type of endoprosthesis that should be implanted after femoral neck fracture differ from one author to another. Some authors prefer implantation of unipolar partial hip endoprosthesis while others prefer bipolar partial endoprosthesis after displaced femoral neck fracture in elderly persons [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Total hip endoprostheses, according to majority, achieve the best longterm clinical outcome.…”