Second-generation cementless total hip arthroplasty. Eight to eleven-year results.

BACKGROUND: Second-generation cementless femoral components were designed to provide more reliable ingrowth and to limit distal osteolysis by incorporating circumferential proximal ingrowth surfaces. We examined the eight to eleven-year results of total hip arthroplasty with a cementless, anatomically designed femoral component and a cementless hemispheric acetabular component. METHODS: Ninety-two consecutive primary total hip arthroplasties with implantation of a femoral component with a circumferential proximal porous coating (Anatomic Hip) and a cementless hemispheric porous-coated acetabular component (Harris-Galante II) were performed in eighty-five patients. These patients were prospectively followed clinically and radiographically. Six patients (seven hips) died and five patients (seven hips) were lost to follow-up, leaving seventy-four patients (seventy-eight hips) who had been followed for a mean of ten years (range, eight to eleven years). The mean age at the time of the arthroplasty was fifty-two years. RESULTS: The mean preoperative Harris hip score of 51 points improved to 94 points at the time of final follow-up; 86% of the hips had a good or excellent result. Thigh pain was reported as mild to severe after seven hip arthroplasties. No femoral component was revised for any reason, and none were loose radiographically at the time of the last follow-up. Two hips underwent acetabular revision (one because of dislocation and one because of loosening). Kaplan-Meier survivorship analysis was performed with revision or loosening of any component as the end point. The ten-year survival rate was 96.4% +/- 2.1% for the total hip prosthesis, 100% for the femoral component, and 96.4% +/- 2.1% for the acetabular component. Radiolucencies adjacent to the nonporous portion of the femoral component were seen in sixty-eight (93%) of the -seventy-three hips with complete radiographic follow-up. Femoral osteolysis proximal to the lesser trochanter was noted in four hips (5%). No osteolysis was identified distal to the lesser trochanter. Periacetabular osteolysis was identified in twelve hips (16%). Five patients underwent exchange of the acetabular liner because of polyethylene wear. CONCLUSIONS: This second-generation cementless, anatomically designed femoral component provided excellent clinical and radiographic results with a 100% survival rate at ten years. The circumferential porous coating of this implant improved ingrowth and prevented distal osteolysis at a mean of ten years after the arthroplasty.

Cementless acetabular reconstruction after acetabular fracture.

BACKGROUND: Total hip arthroplasty in patients with posttraumatic arthritis has produced results inferior to those in patients with nontraumatic arthritis. The use of cementless acetabular reconstruction, however, has not been extensively studied in this clinical context. Our purpose was to compare the intermediate-term results of total hip arthroplasty with a cementless acetabular component in patients with posttraumatic arthritis with those of the same procedure in patients with nontraumatic arthritis. We also compared the results of arthroplasty in patients who had had prior operative treatment of their acetabular fracture with those in patients who had had prior closed treatment of their acetabular fracture. METHODS: Thirty total hip arthroplasties were performed with use of a cementless hemispheric, fiber-metal-mesh-coated acetabular component for the treatment of posttraumatic osteoarthritis after acetabular fracture. The median interval between the fracture and the arthroplasty was thirty-seven months (range, eight to 444 months). The average age at the time of the arthroplasty was fifty-one years (range, twenty-six to eighty-six years), and the average duration of follow-up was sixty-three months (range, twenty-four to 140 months). Fifteen patients had had prior open reduction and internal fixation of their acetabular fracture (open-reduction group), and fifteen patients had had closed treatment of the acetabular fracture (closed-treatment group). The results of these thirty hip reconstructions were compared with the intermediate-term results of 204 consecutive primary total hip arthroplasties with cementless acetabular reconstruction in patients with nontraumatic arthritis. RESULTS: Operative time (p < 0.001), blood loss (p < 0.001), and perioperative transfusion requirements (p < 0.001) were greater in the patients with posttraumatic arthritis than they were in the patients with nontraumatic arthritis. Of the patients with posttraumatic arthritis, those who had had open reduction and internal fixation of their acetabular fracture had a significantly longer index procedure (p = 0.01), greater blood loss (p = 0.008), and a higher transfusion requirement (p = 0.049) than those in whom the fracture had been treated by closed methods. Eight of the fifteen patients with a previous open reduction and internal fixation required an elevated acetabular liner compared with one of the fifteen patients who had been treated by closed means (p = 0.005). Two of the fifteen patients with a previous open reduction and internal fixation required bone-grafting of acetabular defects compared with seven of the fifteen patients treated by closed means (p = 0.04). The thirty patients treated for posttraumatic arthritis had an average preoperative Harris hip score of 41 points, which increased to 88 points at the time of follow-up; there was no significant difference between the open-reduction and closed-treatment groups (p = 0.39). Twenty-seven patients (90%) had a good or excellent result. There were no dislocations or deep infections. The Kaplan-Meier ten-year survival rate, with revision or radiographic loosening as the end point, was 97%. These results were similar to those of the patients who underwent primary total hip arthroplasty for nontraumatic arthritis. CONCLUSIONS: The intermediate-term clinical results of total hip arthroplasty with cementless acetabular reconstruction for posttraumatic osteoarthritis after acetabular fracture were similar to those after the same procedure for nontraumatic arthritis, regardless of whether the acetabular fracture had been internally fixed initially. However, total hip arthroplasty after acetabular fracture was a longer procedure with greater blood loss, especially in patients with previous open reduction and internal fixation. Previous open reduction and internal fixation predisposed the hip to more intraoperative instability but less bone deficiency.

Hybrid total hip arthroplasty with a precoated offset stem. Four to nine-year results.

BACKGROUND: Use of modern cementing techniques for fixation of femoral components in total hip arthroplasty has had excellent clinical and radiographic results in most patients. However, several authors have described early loosening of femoral components with roughened and precoated finishes. The purpose of this study was to examine the performance of the precoated Iowa stem, which has increased offset, and to compare the results with those of another cemented precoated femoral component with standard offset used at our institution. METHODS: We carried out a prospective analysis of 102 primary hybrid total hip arthroplasties (a cementless acetabular component and a cemented femoral component) performed with use of the Iowa femoral component in ninety-five patients at our institution. The Iowa stem was used in hips that required greater offset than is available with standard stems as determined by preoperative templating. The average age of the patients at the time of the index procedure was sixty-nine years. Sixteen patients (seventeen hips) died before the forty-eight-month minimum follow-up period had elapsed. Two patients were lost to follow-up, and radiographic follow-up was incomplete for one. The mean duration of clinical and radiographic follow-up of the remaining eighty-two hips in the seventy-six surviving patients was sixty-five months (range, forty-eight to 104 months). RESULTS: The average preoperative Harris hip score of 47 points (range, 16 to 69 points) improved to an average of 87 points (range, 24 to 100 points) at the time of the review. Two hips underwent femoral component revision. Four femoral stems were radiographically loose at an average of thirty-four months. Femoral osteolysis was seen in five hips (6 percent) at an average of fifty-four months postoperatively. No acetabular component was revised because of aseptic loosening. According to Kaplan-Meier analysis, the seven-year survival rate, with an end point of femoral revision, osteolysis, or stem debonding, was 90.6 percent (95 percent confidence interval, 0.87 to 0.94). CONCLUSIONS: The prevalence of revision, osteolysis, and loosening after total hip arthroplasty with the Iowa femoral component at our institution was higher than that seen in our series of Harris Precoat stems, which had a survival rate of 98.4 percent (95 percent confidence interval, 0.97 to 1.00) at ten years with the same end points. The design of the Iowa stem may make it difficult to achieve a good cement mantle, and, in combination with the geometry and increased offset of the stem, may compromise the long-term survival of this cemented femoral component.

The fate of stable cemented acetabular components retained during revision of a femoral component of a total hip arthroplasty.

BACKGROUND: The decision as to whether to revise or retain a well fixed cemented acetabular component during revision of a femoral component is especially difficult; the rate of loosening of cemented acetabular components is high, whereas that of porous-coated acetabular components inserted during revision is low. However, removal of a well fixed cemented acetabular component can result in increased operative morbidity and cost and in loss of acetabular bone. Data that can be used to predict the long-term survival of retained well fixed cemented acetabular components are therefore needed. METHODS: We studied the five to thirteen-year clinical and radiographic results in a group of twenty-six consecutive patients in whom a well fixed cemented acetabular component had been retained during revision of a femoral component. Typical demographic data on the patients and information about the components were recorded, and the cemented acetabular components were graded as A through F, according to the system of Ranawat et al., at the time of the femoral revision. The average duration of follow-up was 8.4 years (range, 5.0 to 12.7 years). No patient was lost to follow-up. RESULTS: Four acetabular components (15 percent) had progressive radiolucency (at forty-eight, forty-eight, fifty-nine, and seventy-five months after the femoral revision) and were considered radiographically loose despite not being associated with symptoms. All four components were graded as either E or F at the time that they were retained during the femoral revision; radiographic loosening was significantly related to these two grades (p < 0.01). No acetabular component with a grade of A, B, C, or D loosened. The components that loosened had been in vivo for a relatively shorter, as opposed to longer, duration before the femoral revision compared with the components that did not loosen (p < 0.05). CONCLUSIONS: Retention of the well fixed cemented acetabular components was associated with good clinical results but with a 15 percent rate of loosening. Revision of a cemented acetabular component solely on the basis of the duration that it was in vivo or whether a previous revision had been done does not appear to be warranted. Our findings suggest that acetabular components with a grade of A, B, C, or D at the time of a femoral revision may be retained, as these components continued to function at the time of the five to thirteen-year follow-up in the current study.

Cementless acetabular revision. Evaluation at an average of 10.5 years.

This study reviews the clinical and radiographic results of 138 consecutive cementless acetabular revisions in 131 patients performed for aseptic loosening at a mean of 10.5 years followup. Kaplan-Meier survivorship of these components was 84% at 11.5 years. Two components (1.8%) in two patients were considered aseptically loose based on radiographic criteria; one patient was symptomatic but the component was not revised because of the patient's poor health, and the other patient was asymptomatic. Pelvic osteolysis was present in 19 hips (17%), appearing at a mean of 103 months. All but two of these were small lesions (< 2 cm) at the periphery of the components. Nevertheless, the incidence of osteolysis has increased with time, and continued followup is warranted. Separation or fragmentation of the fiber-metal porous pads was uncommon (8.3%), but was significantly associated with pelvic osteolysis; this finding has not been reported before with this component. Five patients underwent late revision surgery (after 100 months), one for deep infection, one for periprosthetic femur fracture, and three for late recurrent dislocation. Harris hip scores averaged 81 points (good) at final followup, which is unchanged from the authors' last report on this group. Acetabular revision with a fiber-metal hemispherical component appears durable at a mean followup of more than 10 years.

Impaction allografting with cement for revision of the femoral component. A minimum four-year follow-up study with use of a precoated femoral stem.

BACKGROUND: Cancellous impaction allografting with cement for revision of the femoral component has conventionally been performed with a polished, tapered implant, which was designed to allow subsidence of the component. However, subsidence has been associated with pain in the thigh, dislocation of the hip, and revision of the component. This prospective study tested the hypothesis that good clinical results can be achieved--without subsidence of the component--with use of impaction allografting and a precoated, collared, straight stem for difficult femoral revisions. METHODS: Twenty-nine patients had revision of the femoral component with use of impaction allografting with cement and a Harris Precoat stem. Impaction allografting was performed when loss of metaphyseal and diaphyseal bone precluded revision with more straightforward techniques or when reconstitution of bone was considered a specific goal of the reconstruction (as was sometimes the case with revision of the component in younger patients). The patients were followed prospectively and were evaluated with use of the Harris hip score and serial radiographs. The patients were followed for a minimum of four years (mean, sixty-three months), except for four who died. RESULTS: Four patients died before the minimum four-year follow-up period had elapsed; all four had the prosthesis in place at the time of death. The Harris hip scores improved from a preoperative mean of 54 points (poor) (range, 21 to 91 points) to a mean of 87 points (good) (range, 41 to 100 points) at the time of the most recent follow-up. Kaplan-Meier survivorship analysis, with aseptic loosening as the end point, was 92 percent (95 percent confidence interval, 82 to 100 percent) at six years; one additional hip failed because of a hematogenous infection at seventy-three months postoperatively, for an overall failure rate of 12 percent (three of twenty-five patients) at the time of the most recent follow-up. Two hips needed a repeat revision; one was revised because of subsidence of the stem with recurrent osteolysis and the other, in a patient who had hemodialysis, because of late sepsis. A third femoral component subsided and failed but was not revised. Radiographic evidence of bone-stock reconstitution was observed in six (29 percent) of the twenty-one patients for whom radiographs were available. As in other series of patients managed with impaction allografting, the complication rate was high; excluding the revisions, three reoperations were performed, and six patients had either intraoperative femoral fracture or perforation necessitating cerclage wiring or cortical strut allografting and cerclage wiring at the time of the procedure. There were six nonunions in eighteen patients who had been operated on with a transtrochanteric approach. CONCLUSIONS: Difficult revisions of the femoral component with use of impaction allografting and a precoated stem provided satisfactory clinical and radiographic results at the time of intermediate-term follow-up. However, the high rate of complications in our series led us to refine our indications for the procedure.

Primary cementless acetabular reconstruction in patients younger than 50 years old. 7- to 11-year results.

The efficacy of primary cementless acetabular reconstruction in patients younger than 50 years of age was analyzed in 79 consecutive cementless, hemispheric, porous coated acetabular reconstructions (Harris-Galante-I). The average age was 37 years at surgery (range, 20-49 years). The average followup was 106 months (range, 78-126 months). No acetabular reconstructions were revised for aseptic loosening. Two stable acetabular reconstructions were revised during femoral revision. Two excessively worn polyethylene liners were exchanged and one acetabular osteolytic area was debrided and grafted; these procedures retained the metal shell. At final followup, all 72 acetabular reconstructions were radiographically stable. Acetabular osteolysis occurred in five cases (7.4%), from 84 to 104 months. Acetabular or femoral osteolysis occurred in patients with increased polyethylene wear. Polyethylene wear was inversely related to the patient's age. Using revision and loosening, the Kaplan-Meier 10 year survival of the acetabular reconstruction was 98.8% (95% confidence interval, 96.6%-100.%). The intermediate results of cementless, hemispheric, porous coated acetabular reconstruction in younger patients was excellent with no radiographic loosening. At 7- to 11-year followup, osteolysis was the most common problem and increased in frequency and extent with continued in vivo duration.