Philip M. Faris

Postoperative alignment of total knee replacement. Its effect on survival.

Four hundred twenty-one posterior cruciate condylar total knee arthroplasties were performed between 1975 and 1983. Anatomic alignment of the knee was recorded on follow-up evaluations from two months to 13 years postoperatively. Patients were stratified into a normal group that was 5 degrees to 8 degrees anatomic valgus, a varus group that was from 4 degrees anatomic valgus to any degree of varus, and a valgus group that was more than 9 degrees anatomic valgus. There were eight failures, five in the varus group and three in the normal group. There were no failures in the valgus group. Kaplan-Meier survival curves showed no significant difference between normal and valgus groups; however, there was a statistical difference between the valgus and varus and the normal and varus groups. A surgeon should align a total knee prosthesis in neutral or a slight amount of anatomic valgus to give the patient the best chance for long-term survival.

The Chetranjan Ranawat Award: Tibial Component Failure Mechanisms in Total Knee Arthroplasty

The purpose of this study was to examine the failure mechanisms and factors associated with failure of a nonmodular metal backed cemented tibial component. Out of 3152 total knee replacements done for osteoarthritis, 41 tibial components had been revised (1.3%). Four distinct failure mechanisms were identified: 20 knees were revised for medial bone collapse, 13 for ligamentous imbalance, 6 for progressive radiolucencies, and 2 for pain. Factors associated with medial bone collapse were varus tibial component alignment more than 3.0°, Body Mass Index higher than 33.7, and overall postoperative varus limb alignment. Ligamentous imbalance was more prevalent in knees with preoperative valgus deformity. There were no knees revised for tibial component polyethylene wear or osteolysis. We conclude that the dominant failure mechanisms for this component design are related to preoperative deformity, technical factors of component alignment, overall limb alignment, and ligamentous imbalance.

Long-term followup of anatomic graduated components posterior cruciate-retaining total knee replacement.

The purpose of the current study was to evaluate the authors’ 15-year experience with the Anatomic Graduated Components total knee replacement. This is a report of the survivorship of 4583 Anatomic Graduated Component total knee arthroplasties. Kaplan-Meier survival analyses were performed with the end point defined as radiographic loosening, revision, or both. This end point was subdivided into the best case scenario in which it was assumed that all the patients lost to followup were doing well throughout the study and a worst case scenario in which it was assumed that all patients lost to followup had failed results at their last clinic visit. There were six (0.18%) femoral, 21 (0.46%) tibial, and 180 (4.2%) all-polyethylene patellar component failures secondary to aseptic loosening. All femoral components and 90% of the tibial components were revised; however, only 15 patellar components were revised. The clinical survival rate with revision of one or more of the components was 98.86% at 15 years. Despite having nearly flat-on-flat geometry and retaining the posterior cruciate ligament, which should increase the stresses in the polyethylene and at the bone-cement interface, this total knee replacement has proved to have minimal wear and excellent longevity with time. The authors think this is a result of the direct compression molded polyethylene articulation and the nonmodular configuration that incorporates metal backing on the tibial component and eliminates back-sided tibial component polyethylene wear.

Impaction Bone-Grafting before Insertion of a Femoral Stem with Cement in Revision Total Hip Arthroplasty. A Minimum Two-Year Follow-up Study*

Impaction bone-grafting was performed before insertion of a collarless, polished, tapered femoral stem with cement in thirty-four revision total hip arthroplasties (thirty-four patients) that were done because of aseptic loosening. The average duration of follow-up was thirty months (range, twenty-four to forty-two months). The operation was the initial revision in twenty-eight patients (82 per cent). Twenty-two patients (65 per cent) also had revision of the acetabular component. Complications included four intraoperative and two postoperative fractures of the femur as well as one dislocation (at one month). Two patients (6 per cent) needed a repeat revision of the femoral stem because of aseptic loosening at twenty-six and thirty-six months postoperatively. Both of these patients had an associated fracture of the femur (one was intraoperative, and the other was postoperative). Subsidence was common (thirteen patients; 38 per cent) and averaged 10.1 millimeters (range, four to thirty-one millimeters). Although the study group was relatively small, with the numbers available subsidence was not found to be associated with the preoperative or postoperative hip score, segmental or cavitary femoral defects, femoral ectasia, intraoperative fracture of the femur, strut-grafting, trochanteric osteotomy, or varus position of the femoral component. Incorporation of the allograft into the trabecular bone and secondary remodeling were noted radiographically in thirty-two (94 per cent) and fourteen (41 per cent) of the patients, respectively, often within one year. Although the duration of follow-up was relatively short, no localized resorption of the allograft occurred and cortical repair was noted in one patient at three years. At the most recent follow-up evaluation, the Harris hip scores had improved from a preoperative average of 51 points (range, 32 to 90 points) to an average of 87 points (range, 65 to 100 points) and twenty-eight patients (82 per cent) had no or only slight pain. Despite the satisfactory early clinical results, we remain concerned about the high rate of fracture of the femur and the rate and extent of subsidence of the femoral component. On the basis of the worrisome findings after this two-year period, we recommend that impaction bone-grafting be used only when proximal femoral osteopenia is so severe that stability cannot be obtained with insertion of a long-stemmed femoral component without cement. In that setting, impaction bone-grafting may be considered instead of implantation of a massive proximal femoral allograft in combination with insertion of a femoral component with cement.

Comparative Outcomes of Total Joint Arthroplasty

A prospective pre- and postoperative general health/quality-of-life factor comparison, using the Rand SF-36 Health Status Questionnaire (TyPE Specification, Quality Quest [Health Outcomes Institute, Minneapolis, MN]), was carried out on a consecutive series of patients with diagnosed osteoarthritis undergoing total hip and knee arthroplasty between March 1991 and March 1994. Study groups consisted of 85 total hip arthroplasty patients, 93 total knee arthroplasty patients, and 65 single-stage bilateral total knee arthroplasty patients, all treated at the same specialty hospital, under the care of three senior orthopaedic surgeons. The average patient age was 69 years. Significant improvements in quality-of-life measures including physical functioning, social functioning, role functioning/physical problem, role functioning/emotional problem, mental health, energy/fatigue, pain, and change in health were noted in all hip and knee arthroplasty patients 6 months, 1 year, and 2 years after surgery (P < .05). There appeared to be no significant differences in quality-of-life measures between hip and knee arthroplasty patients. Results therefore indicate that total hip and knee arthroplasty significantly improve the functional status and quality of life among patients suffering from osteoarthritis.

Unwashed filtered shed blood collected after knee and hip arthroplasties. A source of autologous red blood cells.

We evaluated the results of twelve hematological and plasma protein determinations in 450 to 500-milliliter volumes of shed blood that had been collected with or without acid-citrate-dextrose anticoagulant (National Institutes of Health Formula A) from knees and hips during the first twelve hours after arthroplasty. We also evaluated the effects on the recipients when the blood was used for reinfusion. The findings in the units that had been obtained in less than four hours, in between four and six hours, and in more than six hours after the arthroplasty were similar whether or not the acid-citrate-dextrose anticoagulant had been used. The mean values for the collected units were: in the blood, a concentration of hemoglobin of 115 grams per liter, a hematocrit of 0.34, a white blood-cell count of 4.8 x 10(9) per liter, and a red blood-cell count of 3.7 x 10(12) per liter, and, in the plasma, a level of hemoglobin of 160 grams per liter, a level of fibrinogen of less than 0.2 gram per liter, a level of factor-V clotting protein of less than 10 per cent of normal, a level of factor-VIII clotting protein that was 45 per cent of normal, a level of antithrombin III that was 45 per cent of normal, a level of plasminogen that was 55 per cent of normal, a level of protein C that was 100 per cent of normal, and a level of fibrin-degradation products of 1000 micrograms per milliliter of plasma. The clinical response of the patient was assessed after the reinfusion of a total of 205 units of unwashed shed blood into 153 patients. In addition, in 126 of the 153 patients, hematological and plasma-protein measurements were analyzed before the autotransfusion and one and twenty-four hours afterward. Each of these patients had received one to four units of shed blood that had been filtered but not washed. Only two (2 per cent) of the ninety-nine patients who received shed blood that had been collected six hours or less after the operation had a febrile reaction, whereas twelve (22 per cent) of the fifty-four patients who received blood that had been collected six to twelve hours after the operation had such a reaction.(ABSTRACT TRUNCATED AT 400 WORDS)

Long-term followup of nonmodular total knee replacements.

The purpose of the current study was to evaluate and determine the mechanism and etiology of failure of components that failed in long-term followup of Anatomic Graduated Component total knee replacements. The authors previously reported the survivorship of 4583 Anatomic Graduated Component total knee arthroplasties done during a 17-year period. The current study was done to evaluate the etiology and cause of failure of the components that failed. There were six (0.18%) failures of the femoral component. There were 21 tibia components that failed (0.46%). Twelve tibial components failed because of an osteonecrotic lesion in the medial tibia plateau. The clinical survival rate with revision or loosening of one or more components was 98.9% at 15 years. No component was revised for polyethylene wear or osteolysis. This total knee replacement has proved to have minimal wear and excellent longevity with time with no revisions between 10 and 15 years despite having nearly flat-on-flat geometry and retaining the posterior cruciate ligament. The most common cause for revision (12 tibial components) was because of an osteonecrotic lesion in the medial tibia plateau, which developed after surgery and led to loosening.

Radiolucency at the bone-cement interface in total knee replacement. The effects of bone-surface preparation and cement technique.

Three hundred and sixty-three knees (221 patients) that had been treated with total arthroplasty between 1975 and 1985 were divided into three groups on the basis of the preparation of the surface of the bone and the technique of the cement application. Group 1 (155 knees) was treated with irrigation of the bone surfaces with a syringe and manual packing of the bone cement. Group 2 (sixty-one knees) had high-volume, high-pressure lavage of the bone surfaces and manual packing of the cement. Group 3 (147 knees) had high-volume, high-pressure lavage and pressure injection of low-viscosity methylmethacrylate cement. Radiolucency was evaluated at each follow-up interval, and the findings were subjected to chi-square analysis and Kaplan-Meier survival analysis. Chi-square analysis of the data at one and three years indicated a significantly higher frequency of lines at the bone-cement interface in the femur and tibia in Group-1 knees compared with those in Groups 2 and 3. The survival curves showed increasing rates of radiolucency adjacent to the tibial components of the knees that had been prepared with lavage that was not high-volume and high-pressure and that had been prepared with finger-packing of cement (Group 1). This may partially explain the clinical problem of loosening of tibial components despite acceptable alignment. This study demonstrates that proper preparation of the cancellous bone and pressurization of the cement reduce the initial occurrence of a radiolucent line, which may have a positive effect on the ultimate failure of at least the tibial component.

Anterior femoral notching and ipsilateral supracondylar femur fracture in total knee arthroplasty

The authors reviewed 670 total knee arthroplasties with a 2-10-year follow-up period. Of these, 180 knees had anterior femoral notching, which was deeper than 3 mm in 138. Two of the 670 knees suffered ipsilateral supracondylar fractures; one of these had a notched femur and one did not. Both fractures occurred at the anterior patellar flange-bone junction. No correlation was found between anterior femoral notching and ipsilateral supracondylar femur fracture.

Long-term survival analysis of the posterior cruciate condylar total knee arthroplasty. A 10-year evaluation.

Abstract Long-term survivorship analysis was applied to 394 cruciate condylar type total knee arthroplasties. Clinical and radiographic parameters were evaluated. Failure was defined in three separate survival curves as revision, radiographic loosening, and a pain rating of 20 or less on the HSS knee score scale. Survival at 10 years, using only revision or recommended revision as the criterion for failure, was 94.7% With the addition of the other two criteria, survival fell to 81% at 10 years. The posterior cruciate condylar knee survival is comparable to that of the total condylar knee when using comparable definitions of failure.