-
A V Lombardi,
T H Mallory,
M M Alexiades,
J M Cuckler,
P M Faris,
K A Jaffe, E M Keating,
C L Nelson,
C S Ranawat,
J Williams,
R Wixson,
J F Hartman,
S G Capps,
C A Kefauver
[show abstract]
[hide abstract]
ABSTRACT: A polyethylene-free, metal-on-metal acetabular system (M2a-taper [Biomet, Inc., Warsaw, IN]) was designed in an effort to improve total hip arthroplasty (THA) longevity. Minimum 2-year follow-up results involving 72 polyethylene liner THAs and 78 metal liner THAs from a multicenter, randomized, controlled, investigational device exemption study are reported. Mean Harris hip scores of 95.54 (polyethylene liner group) and 95.23 (metal liner group) were reported at mean follow-up intervals of 3.29 and 3.23 years. Radiographic evaluation revealed no evidence of early failure. No acetabular components have been revised or are pending revision. No statistically significant differences in the data were calculated between liner types except for the immediate postoperative (P=.0415) and minimum 2-year follow-up (P=.0341) angles of inclination. The M2a-taper metal-on-metal articulation may represent a viable alternative for THA in younger, higher demand patients.
The Journal of Arthroplasty 01/2002; 16(8 Suppl 1):122-8. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Between June 1987 and March 1997, 57 total knee replacements were done in 53 patients with at least 5 degrees hyperextension deformity as measured on physical examination. The average recurvatum measured 11 degrees (range, 5 degrees-20 degrees). No cases of major ligamentous instability, neuromuscular disease, or inflammatory arthropathy were identified before surgery. Before surgery, Knee Society knee, function, and pain scores averaged 41 points, 41 points, and 13 points, respectively. A posterior cruciate-retaining prosthesis was implanted in all patients. The followup averaged 4.5 years (range, 3-10 years). Knee, function, and pain scores improved to 81 points, 78 points, and 43 points, respectively. Postoperative extension averaged 0 degrees (neutral) (range, 10 degrees hyperextension-10 degrees contracture). Only two (3.5%) knees had a hyperextension deformity after surgery. Both deformities measured 10 degrees and were in patients with a preoperative diagnosis of osteoarthritis. At final followup, no knee replacement was revised for any reason. In addition, only one case of a progressive radiolucent line greater than 1 mm (tibial Zone 7) was observed. Although the etiology of a hyperextension deformity should be elucidated before surgery, its presence does not preclude a well-functioning total knee replacement.
Clinical Orthopaedics and Related Research 01/2002; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: As the number of total knee arthroplasties performed each year in the United States continues to increase, knowledge of long-term prosthetic performance and implant durability is paramount. A selection of the best total knee replacement system for a given patient should be based on long-term followup studies reviewing, among other parameters, survivorship and complications. The importance of such long-term data should not be underestimated.
Clinical Orthopaedics and Related Research 08/2001; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The patellar component of total knee replacement is the most frequent source of nonseptic complications after total knee arthroplasty. The purpose of the current study was to review the radiographic factors associated with loosening of all-polyethylene patellar components. Four thousand five hundred eighty-three cases of Anatomic Graduated Components total knee replacements were performed at the authors' institution during the past 15 years. Radiographs were reviewed and loosening was defined as global radiolucency or component migration. Four thousand two hundred eighty-seven allpolyethylene patellar components were implanted. There were 180 (4.2%) loose all-polyethylene patellar components. The mean time to loosening was 2.6 years (+/- 1.75 years). Fifteen (0.3%) patellar components required revision. Five radiographic features were associated with failure. The incidence and mean time of appearance were recorded: (number; incidence; time) (1) Bone-cement radiolucency, n = 174, 96.7%, 1.4 years; (2) increased density, n = 118, 65.6%, 1.8 years; (3) trabecular collapse of the bone, n = 160, 88.9%, 2.3 years; (4) patella fracture and fragmentation, n = 133, 73.9%, 2.5 years; and (5) lateral subluxation of the residual patella bone, n = 146, 81.1%, 2.9 years. Lateral retinacular release was associated with an increased rate of patellar loosening. Loosening of the allpolyethylene patella component is an avascular process strongly associated with lateral retinacular release and for which the patient infrequently requires revision surgery.
Clinical Orthopaedics and Related Research 08/2001; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: 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.
Clinical Orthopaedics and Related Research 08/2001; · 2.53 Impact Factor
-
The Journal of Bone and Joint Surgery 03/2001; 83-A(2):298-9. · 3.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This controlled study compared the strength and porosity of 48 polymethylmethacrylate cement-implant constructs prepared with open bowl versus vacuum mix technique. Forty-eight blast finished stainless steel rods of 13 mm diameter were implanted with centralizers into 17-mm inner diameter tubes that had been retrograde filled with polymethylmethacrylate cement. The eight cement preparations used were open bowl and vacuum mixed Simplex, Osteobond, Zimmer Dough Type, or Palacos R. Six replications of each condition were performed. The tubes were maintained at 37 degrees C. Each tube was cut transversely into five segments. The center three segments were used for data analysis: pushout strength, cycles to failure, and interface porosity analysis. Rod pushout data showed there was no significant difference between open bowl and vacuum mixed samples when all cement brands were combined. Mean sheer force for Palacos R vacuum mixed samples was greater than open bowl (634+/-47 versus 423+/-171), whereas the force for the Zimmer Dough Type cement open bowl was greater than that of the vacuum mixed samples (901+/-71 versus 705 +/-82). Cycles to failure data did not show significant differences when open bowl and vacuum mixed samples were compared when cements were analyzed individually or combined. Image analysis of cement-implant interfaces showed that vacuum mixing reduced void area significantly compared with open bowl mixing in the Palacos R and Osteobond preparations. Vacuum mixing does not appear to reduce cement prosthesis interface porosity or improve its mechanical properties in all cements.
Clinical Orthopaedics and Related Research 02/2001; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The preoperative radiographs of 1,888 patients undergoing 2,759 consecutive total knee arthroplasties (TKAs) performed for osteoarthritis (OA) were retrospectively reviewed to test the hypothesis that patients with less severe OA changes experience less pain relief and lower function scores after TKA. Age at surgery averaged 70.6 years, and follow-up averaged 2.5 years. Preoperatively, pain was independent of an arthritis grade, and this likewise was noted at > or =3 years after surgery. Patients with severe and mild radiographic changes of OA eventually experienced the same degree of function and pain relief after TKA.
The Journal of Arthroplasty 01/2001; 16(1):13-6. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The outcome of total knee replacement after high tibial osteotomy remains uncertain. We hypothesized that the results of total knee replacement with or without a previous high tibial osteotomy are similar.
The results of a consecutive series of thirty-nine bilateral total knee arthroplasties performed with cement at an average of 8.7 years after unilateral high tibial osteotomy were reviewed. There were twenty-seven men and twelve women. Preoperatively, the knee scores according to the system of the Knee Society were similar for all of the knees; however, valgus alignment and patella infera were more common in the knees with a previous high tibial osteotomy. Bilateral total knee replacement was staged in seven patients and was simultaneous in thirty-two patients. The results of the total knee arthroplasties were retrospectively reviewed with respect to the knee and function scores according to the system of the Knee Society, the radiographic findings, and the complications.
Intraoperatively, no notable differences were identified in the number of medial, lateral, or lateral patellar releases required. However, less lateral tibial bone was resected in the group with a previous high tibial osteotomy (average, 3.3 millimeters) than in the group without a high tibial osteotomy (average, 7.5 millimeters). The average duration of follow-up was 7.5 years (range, three to sixteen years) in the group with a previous high tibial osteotomy and 6.8 years (range, two to ten years) in the group without a high tibial osteotomy. At the time of the final follow-up, the knee and function scores were similar for the two groups (89.0 and 81.0 points, respectively, for the group with a previous high tibial osteotomy, and 89.6 and 83.9 points, respectively, for the group without a high tibial osteotomy). Although more knees were free of pain in the group without a previous high tibial osteotomy (thirty-six) than in the group with a previous osteotomy (thirty-three), this difference was not found to be significant with the numbers available (p = 0.4810). Knee alignment and stability, femoral and tibial component alignment, and range of motion also were similar in both groups postoperatively. One allpolyethylene tibial component was revised in the high tibial osteotomy group. Two knees in each group required manipulation. There were no deep infections.
While patients with a previous high tibial osteotomy may have important differences preoperatively, including valgus alignment, patella infera, and decreased bone stock in the proximal part of the tibia, the present study suggests that the clinical and radiographic results of primary total knee arthroplasty in knees with and without a previous high tibial osteotomy are not substantially different. In our relatively small group of patients, the previous high tibial osteotomy had no adverse effect on the outcome of the subsequent total knee replacement.
The Journal of Bone and Joint Surgery 10/2000; 82(9):1252-9. · 3.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Windswept deformity, when an individual has 1 knee in extreme varus alignment and the other in severe valgus alignment, is an unusual occurrence in patients presenting for bilateral total knee arthroplasty. This condition was evaluated in 22 patients to examine possible differences between knees in the same individual. Differences between the varus and valgus knees included alignment (P = .0001), as expected, and the position of the lateral joint line (P = .0161) preoperatively. No significant differences were observed between these 2 knee categories in any other comparison preoperatively or postoperatively. Total knee arthroplasty in patients with windswept deformity can be expected to be successful in both knees when attention is given to proper alignment and soft tissue balancing intraoperatively.
The Journal of Arthroplasty 09/2000; 15(5):562-6. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The preoperative radiographs of 1015 patients undergoing 1163 total hip replacements for osteoarthritis were evaluated to determine if a relationship exists between the extent of osteoarthritis and the clinical results of a total hip replacement. Preoperative radiographs were graded with respect to the degree of cartilage space loss, direction of cartilage space loss (femoral head migration), and severity of osteophyte formation. Followup averaged 32.1 months (range, 6-93 months). Greater degrees of cartilage space loss correlated with lower hip scores preoperatively but were unrelated to preoperative pain. These patients had statistically less pain at 6 months and 1 year. Patients with superior cartilage space loss before surgery also had statistically less pain at 6 months. However, at 3 years and beyond, pain was independent of degree of preoperative cartilage space loss, osteophyte formation, or femoral head migration. In addition, hip scores at any followup were independent of the degree of osteoarthritis observed on the preoperative radiograph. These findings provide statistical support to the concept that greater degrees of joint space loss correlate with better relief of pain and less severe joint space loss correlates with less relief of pain within the first year after total hip replacement. At 3 years and beyond, hip and pain scores were independent of the degree of preoperative osteoarthritis.
Clinical Orthopaedics and Related Research 08/2000; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Between 1980 and 1995, 95 consecutive total knee replacements were performed at an average of 10 years 4 months after high tibial osteotomy. The average age of the 82 patients was 66 years, with a preoperative diagnosis of osteoarthritis in 94 knees. One patient died 6 months after surgery. The followup of the remaining 81 patients (94 knees) averaged 8.6 years (range, 2-17 years). Knee Society knee score at final followup improved to an average of 87.6 points from a preoperative average of 38.1 points. No pain was present in 86.2% of knees, and 12.8% of knees had only mild or occasional pain. Tibial radiolucencies were identified in 12 (12.8%) knees at final followup, and in only four knees were radiolucent lines found about the lateral zones. Only one tibial component required revision 3 years after surgery. Although no preoperative factor was identified that predisposed to an inferior knee score, function score, or pain score, the severity of the preoperative flexion contracture and the number of previous surgeries did relate to diminished postoperative motion. However, an increased number of patellar radiolucencies were seen in the knees in which the lateral joint line was raised (referenced from the fibular head) a greater degree. The clinical results of total knee replacement after high tibial osteotomy appeared similar to those of primary total knee replacement. The previous high tibial osteotomy had no adverse effect on the eventual results of a cemented posterior cruciate retaining total knee replacement.
Clinical Orthopaedics and Related Research 07/2000; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: All patients who underwent primary total knee arthroplasty (TKA), revision TKA, primary total hip arthroplasty (THA), and revision THA between January 1, 1990, and December 31, 1996, were retrospectively reviewed to determine the incidence of fatal pulmonary emboli. All TKA patients received 1,000 U of intravenous heparin sodium before the tourniquet was inflated and an additional 500 U of intravenous heparin sodium before the inflation of the second tourniquet during bilateral TKA. All THA patients received 1,000 U of intravenous heparin sodium at the time of the skin incision and 500 U of intravenous heparin sodium before preparation of the femoral canal. The overall incidence of fatal pulmonary emboli was extremely low (TKA, 0.096%; THA, 0.16%). With this regimen of intravenous intraoperative heparin, postoperative aspirin, thromboembolic disease hose, and early ambulation, there is no risk of postoperative bleeding, it is inexpensive, and there is no concern on how long to keep the patients on this regimen postoperatively. We recommend this regimen for the prevention of fatal pulmonary emboli after total joint arthroplasty.
The Journal of Arthroplasty 02/2000; 15(1):16-21. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Total hip and total knee arthroplasties (n = 951) were retrospectively reviewed to determine the cost-effectiveness of routine pathologic examination of surgical specimens in primary total hip and total knee replacements. Discrepancies between the postoperative diagnosis and the final pathologic diagnoses were recorded. Of the 951 cases reviewed, 27 (2.8%) noted conflicting postoperative and pathologic diagnosis. In all cases, the discrepancy was between a postoperative diagnosis of osteoarthritis and pathologic diagnosis of avascular necrosis. No new cases of neoplasia or inflammatory arthropathy were noted based on the pathologic interpretation. Sixteen of these discrepancies (5.1%) and were noted in total hip arthroplasties, and 11 (1.7%) were noted in total knee arthroplasties. In no case was postoperative medical or surgical treatment altered. Based on this review, strong consideration should be given to the elimination of routine pathologic evaluation of surgical specimens during primary joint arthroplasty, leaving this pathologic evaluation optional, at the discretion of the orthopaedic surgeon, rather than mandatory.
The Journal of Arthroplasty 02/2000; 15(1):69-71. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A retrospective review was conducted to delineate the natural history of the posteriorly dislocated total hip replacement. A total of 1,036 consecutive total hip replacements were performed between 1989 and 1992. Forty (3.9%) were known to have dislocated posteriorly. Twenty-four of these dislocations occurred after primary replacements, and 16 occurred after revision. Eighty-five percent of the dislocations occurred within 2 months and were reduced closed. No statistical differences were noted between these 2 groups with respect to height, weight, sex, age, and femoral and acetabular anteversion. Nonunion of the greater trochanter, modular femoral neck length, and operative approach appeared to affect hip stability. Twenty-three of the 40 dislocated hips (57.5%) redislocated. Sixteen of the 40 hips (40%) required reoperation for recurrent dislocation. Thirteen of the 16 revisions (81.3%) were successful. A dislocated total hip replacement that has been rendered stable does not preclude one from having a successful total hip replacement, and it does not appear to affect survivorship at intermediate follow-up.
The Journal of Arthroplasty 12/1999; 14(8):964-8. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We have made a retrospective review of 185 cemented Charnley total hip arthroplasties performed between 1970 and 1974 to determine the relationships between radiological variables and failure of the femoral and acetabular components. We measured the acetabular wear, the orientation of the cup, the thickness and consistency of acetabular and femoral cement mantles, radiolucency and femoral alignment. The mean follow-up was for 11.7 years. Femoral loosening was demonstrable radiologically in 15 hips (8.1%), ten (5.4%) of which were revised during the period of follow-up. Only when the first postoperative radiograph showed a thin cement mantle in Gruen zone 5 was there a significant association with failure of the femoral component. There were 12 loose acetabular components (6.5%), nine (4.8%) of which were revised. When the initial radiograph after operation showed radiolucency in DeLee and Charnley zone 1, the incidence of acetabular loosening was 28.21%. If such radiolucency was not present, the incidence of acetabular loosening was only 0.69%. Our findings emphasise the importance of careful cementing.
Journal of Bone and Joint Surgery - British Volume 11/1999; 81(6):982-6. · 2.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: One thousand, one hundred forty-six Anatomic Graduated Component total knee arthroplasties performed between 1987 and 1989 were used to investigate the effects of patellar thickness alone or coupled with lateral retinacular release on initial patellar complications and maximal flexion. Lateral release was found not to be statistically significant regarding radiolucency, patellar prosthesis loosening, or an increase or decrease in flexion. However, total knee arthroplasties in which a lateral release was done, which either saved the superior lateral genicular artery or sacrificed the superior lateral genicular artery, were found to increase the incidence of initial patellar fractures and/or loosening (complications within 1 year) when compared with total knee arthroplasties in which a lateral release was not performed. There was no statistical difference in failure rates regarding fractures and/or loosening of the patella between lateral releases in which the superior lateral genicular artery was saved and the lateral releases in which the superior lateral genicular artery was sacrificed. A difference in postoperative patellar thickness compared with preoperative patellar thickness was found not to be significant to initial patellar fracture and/or loosening, patellar fracture alone, patellar loosening alone, radiolucency, the need for a lateral release, or to an increase or decrease in flexion. Lateral release and patellar thickness had no significant effect on patellar fracture and/or loosening.
Clinical Orthopaedics and Related Research 11/1999; · 2.53 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The postoperative analgesic effects of intra-articular injections of bupivacaine and/or morphine were examined prospectively in 437 patients who had total knee replacement for osteoarthritis. They were divided randomly into four groups. Group I received 10 mg of morphine (1 ml) and 9 ml of saline, group II received 10 ml of bupivacaine (2.5 mg/ml), group III received 10 ml of saline, and group IV received 10 mg of morphine (1 ml) and 9 ml of bupivacaine (2.5 mg/ml). All analgesics administered in the first 24 hours after operation were recorded. The patients rated their pain on the McGill-Melzack scale at 1, 6, 12 and 24 hours. No significant differences were found between any of the groups in the use of Demoral and/or Toradol in 24 hours, the length of stay in hospital or the pain rating at 1, 6, 12 or 24 hours. Patients in groups I and IV, whose injections included morphine, used significantly more morphine in the first 24 postoperative hours than did groups II or III.
Journal of Bone and Joint Surgery - British Volume 04/1999; 81(2):301-3. · 2.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Between July 1986 and November 1989, 437 consecutive primary cemented total hip arthroplasties were performed using a straight-stemmed titanium alloy femoral component. Collared and collarless versions of this identical stem were randomly chosen by computer allowing a comparison between 213 collared stems (198 patients) and 224 collarless stems (209 patients). Diagnosis, sex, weight, and average age (72.8 years, collared; 72.0 years, collarless) were similar. Follow-up averaged 76 months (collared) and 72 months (collarless) with 49 patients followed for at least 10 years. Calcar-collar contact was noted in 205 hips (96%) on the initial postoperative radiograph. Early complications, including dislocations (5% each group), were similar. Late complications included 3 deep infections (2 collared, 1 collarless) and 2 postoperative femur fractures (1 each). Hip scores at the most recent follow-up averaged 91.2 and 90.1 in the collared and collarless groups. No or slight pain was noted in 93% of collared and 91.5% of collarless hips. Although no radiographic differences were noted in distal cortical hypertrophy, stem subsidence, and osteolysis, collarless hips lost significantly more medial femoral neck cortical bone (average 0.90 mm vs 0.63 mm). A higher incidence of radiolucent lines in femoral zone VI (20.7% vs 9.4%) was also noted in collarless hips.
The Journal of Arthroplasty 03/1999; 14(2):123-30. · 2.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A total of 100 patients having bilateral total knee replacements simultaneously were randomized prospectively--one knee having a vastus muscle-splitting approach and the other knee having a median parapatellar approach-to evaluate differences in lateral release, postoperative rehabilitation, ease of approach, and complications in total knee replacement surgery. There were 25 lateral releases on the muscle-splitting side and 26 on the median parapatellar side (P = .871). There were no differences in range of motion on day 2 or discharge, straight-leg raise, terminal knee extension, extensor lag, lateral release, or rehabilitation. There were 2 postoperative hematomas and 1 manipulation, all on the muscle-splitting side. All complications occurred from the muscle-splitting side. The muscle-splitting approach cannot be recommended as being superior to the median parapatellar approach.
The Journal of Arthroplasty 02/1999; 14(1):29-32. · 2.38 Impact Factor
