Modern unicompartmental knee arthroplasty with cement: a three to ten-year follow-up study

BACKGROUND: Unicompartmental arthroplasty is a treatment alternative when only one compartment of the knee is affected with arthritis, but the reported results of this procedure have been variable. The purpose of the present study was to evaluate the results of a modern unicompartmental knee arthroplasty performed with use of a cemented metal-backed prosthesis and surgical instrumentation comparable with that used for total knee replacement. METHODS: The indications for the procedure were osteonecrosis or osteoarthritis associated with full-thickness loss of cartilage that was limited to one tibiofemoral compartment as evaluated on standing and stress radiographs. One hundred and sixty consecutive cemented metal-backed Miller-Galante prostheses in 147 patients were evaluated after a mean duration of follow-up of sixty-six months (range, thirty-six to 112 months). The mean age of the patients at the time of the index procedure was sixty-six years. RESULTS: Three knees were revised because of progression of osteoarthritis in the patellofemoral joint (two knees) or the lateral tibiofemoral compartment (one knee). Two knees had revision of the polyethylene liner. The average Hospital for Special Surgery knee score improved from 59 points preoperatively to 96 points at the time of the review. According to Kaplan-Meier analysis, the ten-year survival rate (with twenty-nine knees at risk) was 94% +/- 3% with revision for any reason or radiographic loosening as the end point. CONCLUSIONS: A modern unicompartmental knee arthroplasty is a valid alternative for patients with unicompartmental tibiofemoral noninflammatory disease. The patient selection must be strict with regard to the status of the patellofemoral joint. The preoperative planning includes stress radiographs to assess the correction of the deformity and the status of the uninvolved compartment. Continued long-term follow-up is necessary to evaluate long-term polyethylene wear.     

The survival of total knee arthroplasty in patients with osteonecrosis of the medial condyle

The results of total knee arthroplasty in patients with osteonecrosis of the medial femoral condyle were examined using Kaplan-Meier survival analysis. The study included 32 osteonecrotic knees with an average final follow-up examination of 3.9 years. For comparison, 63 osteoarthrotic knees with an average final follow-up examination of 4.6 years were also analyzed. The survival rates were calculated using four distinct categories of failure: (1) revision, (2) revision or radiolucency, (3) revision, radiolucency, or pain, and (4) pain. On the basis of pain relief alone, the five-year postoperative success rate was 82% for osteonecrosis (eight knees) and 90% for osteoarthrosis (27 knees), with no significant statistical difference between the two groups.     

Revision total knee arthroplasty for failed unicompartmental replacement

The results in nineteen patients (twenty-one knees) who had a failed unicompartmental knee replacement followed by a revision total knee arthroplasty were evaluated. There were twelve excellent, four good, one fair, and two poor results. The interval between the unicompartmental replacement and the revision total knee arthroplasty ranged from eight months to eight years. At the time of the revision, a major osseous defect was found in sixteen knees (76 per cent). The duration of follow-up after the revision ranged from two to ten years. At the most recent follow-up examination, radiographs revealed at least one radiolucent line in thirteen knees (62 per cent). The technical difficulties associated with the revision operation are evidence that unicondylar arthroplasty is not a conservative procedure that allows a total knee arthroplasty to be done easily later. The results also do not support the argument that a revision performed after failure of a unicondylar arthroplasty is less technically demanding than one performed after a failed primary total knee arthroplasty.     

Osteolytic indicators found in total knee arthroplasty synovial fluid aspirates

Interleukin-1beta and tartrate resistant acid phosphatase concentrations in synovial fluid aspirates were examined to determine if they could be used as indicators of increased synovial inflammation and an osteolytic reaction in patients having total knee arthroplasty. Synovial aspirates were obtained from seven patients with severely osteoarthritic knees that were scheduled for primary total knee arthroplasty and from 20 patients with knees scheduled for total knee arthroplasty revision. Eleven of the revision cases involved titanium alloy prostheses and nine involved cobalt chrome alloy prostheses. The interleukin-1beta and tartrate resistant acid phosphatase concentrations were obtained and compared between the group having primary total knee arthroplasty and the group having revision total knee arthroplasty. The knees having revision surgery had higher concentrations of interleukin-1beta and tartrate resistant acid phosphatase than did the knees having primary total knee arthroplasty. These results indicate a greater inflammatory and osteolytic response in knees having revision surgery. Although the osteoarthritic knees and the knees needing revision surgery in this study are considered to have an inflammatory state, it was only after total knee arthroplasty when particulate wear debris would be present that appreciable concentrations of interleukin-1beta and tartrate resistant acid phosphatase were produced.     

Why are total knee replacements revised?: analysis of early revision in a community knee implant registry

Since 1991, 5760 knee arthroplasty procedures done by 53 surgeons have been registered in a community joint implant registry and were reviewed regarding initial revision done within the healthcare system. The 168 revisions done represented 2.9% of the knee arthroplasties between September 1991 and December 2002. Survival was defined as the absence of revision surgery. Death was considered a censored event. Cumulative survival rates for the different total knee arthroplasty configurations were: cemented total knee arthroplasty with all-polyethylene tibia, 99.2%; cemented total knee arthroplasty with metal-backed tibia, 96.3%; hybrid total knee arthroplasty, 89.3%; and unicondylar knee arthroplasty, 87.2%. Cemented total knee arthroplasty with metal-backed tibia had better survival than hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasty. Cemented total knee arthroplasty with a metal-backed tibia did not have better survival than cemented total knee arthroplasty with an all-polyethylene tibia. Gender was not related to survival. Age was related to survival, with older patients' knees surviving longer. Aseptic loosening or wear was the cause of revision in 40.8% of patients having total knee arthroplasty and 46.6% of patients having unicondylar knee arthroplasty, whereas progression of arthritis necessitated unicondylar knee revision in 51.2% of patients having that procedure. This study presents further evidence of the value of and ongoing need for total joint registries. Cemented total knee arthroplasty with all-polyethylene tibia and with metal-backed tibia showed more than 95% 10-year cumulative survival. Hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasties did not show such good results.     

Simultaneous revision and contralateral primary total knee arthroplasty

BACKGROUND: There is controversy regarding whether simultaneous or staged bilateral total knee arthroplasty should be performed in patients with bilateral gonarthrosis. In addition, revision total knee arthroplasties have been less successful than primary arthroplasties. The purpose of this study was to evaluate the results of simultaneous revision and contralateral primary total knee arthroplasties performed during the same setting. METHODS: The study cohort included 150 knees in seventy-five patients who had undergone revision arthroplasty because of aseptic failure of a total knee arthroplasty and a contralateral primary arthroplasty for severe gonarthrosis under the same anesthetic. The study group was compared with a control group of sixty patients who had severe arthritis in one knee and had undergone unilateral revision total knee arthroplasty on the contralateral side. The duration of follow-up averaged five years in the group treated with the simultaneous arthroplasties and eight years in the control group. Clinical and radiographic results were evaluated with the Knee Society rating system. RESULTS: In the study group, the average knee score improved by 48 points on the side of the primary arthroplasty and by 37 points on the side of the revision. At the last follow-up visit, most (sixty-five) of the seventy-five patients stated that the knee with the revision felt better than the knee with the simultaneously performed primary arthroplasty. In the control group, the average knee score improved by 30 points on the side of the revision arthroplasty. However, forty-five of the sixty patients had a primary total knee arthroplasty on the contralateral side within two years after the index revision arthroplasty; by four years, all sixty patients had undergone a contralateral primary arthroplasty. CONCLUSIONS: We found a favorable outcome in patients who had undergone simultaneous revision and contralateral primary total knee arthroplasties. Despite a lower mean knee score and less motion, most patients seemed to prefer the knee with the revision arthroplasty to the knee with the primary procedure. These results suggest that this combined procedure is a safe and favorable alternative to a staged procedure consisting of revision and subsequent contralateral primary total knee arthroplasty.     

The kinematic total knee arthroplasty

In 86 patients 102 consecutive cemented Kinematic total knee arthroplasties were reviewed 10-15 years after surgery to determine the clinical and radiographic results and to assess the survival rate. The average age of the 65 female and 21 male patients at the time of surgery was 63 years. Forty-six knees were affected by rheumatoid arthritis (RA), 46 by osteoarthritis (OA), 7 by haemophilic arthropathy and 3 by osteonecrosis. One patient (1 knee) was lost to follow-up, and 31 patients (38 knees) died. Eleven knees had been revised for deep infection (4), wear (4), malposition (2) or persistent pain (1). Fifty-two knees were examined at an average follow-up period of 12 years. The mean Knee Society Score of 89 points was the same for RA and AO knees. Also, 92% of the knees caused no pain or only occasional mild pain. There were no cases of aseptic loosening of any component. Progressive radiolucent lines were not seen on the follow-up radiographs (43 knees, mean follow-up 12 years) The 10- and 14-year survival rates with revision as the end-point were 90% (confidence interval, CI: 81%-95%) and 82% (CI: 67%-92%), respectively. In the worst case scenario, with knees lost to follow-up and knees with moderate pain considered as failures, the 10- and 14-year survival rates were 80% (CI: 69%-88%) and 62% (CI: 46%-77%), respectively. The Kinematic total knee arthroplasty yields equally good long-term results in patients with RA and those with OA. Deep infection and wear were the main reasons for revision.     

McKeever hemiarthroplasty of the knee in patients less than sixty years old

BACKGROUND: Knee arthritis in the young patient is a challenging problem that may necessitate surgical treatment. We continue to perform hemiarthroplasty with a metallic tibial implant in selected young patients who, for various reasons, are not candidates for osteotomy, unicompartmental arthroplasty, or total knee arthroplasty. The purpose of the present study was to determine the minimum twelve-year results of this procedure in young patients. METHODS: The original study group consisted of a consecutive series of twenty-four patients (twenty-six knees) who were managed with McKeever tibial hemiarthroplasty for the treatment of unicompartmental osteoarthritis of the knee. All patients were younger than sixty years of age at the time of the index procedure (average age, 44.6 years). During the study period, two patients died and one was lost to follow-up, leaving twenty-one patients (twenty-three knees) available for review. All patients were followed clinically for a minimum of twelve years or until revision. Knee Society knee and functional scores and Tegner scores were determined, and seven of the ten implants were evaluated radiographically. RESULTS: Thirteen knees were revised at an average of eight years after the index procedures. All thirteen knees had an uncomplicated revision to either a unicompartmental arthroplasty or total knee arthroplasty. Ten retained implants were available for clinical review after an average duration of follow-up of 16.8 years. The mean Knee Society knee scores, functional scores, and Tegner scores, available for nine of these ten knees, were 80, 97, and 4.2, respectively. CONCLUSIONS: We believe that the McKeever tibial hemiarthroplasty continues to be a reasonable surgical option for patients who are not candidates for osteotomy and are too young or too active for a unicompartmental or total knee arthroplasty.     

Clinical and radiological outcomes after revision to the low‐contact‐stress mobile‐bearing total knee arthroplasty

Background: The aim of the present study was to investigate the short–medium‐term clinical and radiological outcomes in revision total knee arthroplasty using a mobile‐bearing implant. Methods: Forty patients (42 knees) who had revisions using the New Jersey low‐contact‐stress (LCS) mobile‐bearing total knee arthroplasty between 1996 and 2000 were reviewed. Results: The average age at revision was 71 years (range, 38–86 years) and the average follow up was 6 years (range, 5–9 years). Of the 34 patients reviewed clinically, six had excellent results, and 20 had good results, to give a total of 76% excellent or good results. There were five (15%) fair results and three (9%) poor results. Seven patients required revision of the components. There was one case of instability within the first year of revision, which required only exchange of the polyethylene bearing to achieve a satisfactory clinical outcome. Of the 31 knees reviewed radiologically, progressive radiolucent lines were seen at the bone–cement interface in five (16%) of the femoral components and in two (6%) of the tibial components. Conclusion: Unconstrained LCS mobile‐bearing total knee arthroplasty can be used in revision surgery with satisfactory results after medium‐term follow up (level of evidence: therapeutic level III).     

Outcomes of total hip and knee arthroplasty after cardiac transplantation

The outcomes of 18 primary or revision total hip (THA) and knee arthroplasties (TKA) in 9 patients with cardiac transplants were reviewed. Primary total joint arthroplasties were performed for osteonecrosis (5 hips) or osteoarthritis (5 hips, 4 knees). There were no infections in any of these patients. Final Harris Hip Scores were 71.8 for patients with osteonecrosis and 88.6 for osteoarthritis. Eight of 10 hips were pain-free at final follow-up. Two of the 10 primary THAs required late revision at 7 and 10 years after the index arthroplasty. One patient (2 hips and 1 knee) had chronic bilateral lower extremity pain. Total knee arthroplasty range of motion averaged from 7.5° to 118°. Average final Knee Society function score was 79, and objective score was 88. One of 4 patients with primary TKA required a manipulation under anesthesia. No reoperations were required in this group. Overall, patients with heart transplantations on immunosuppression had generally good pain relief after THA and TKA. There were no infections in this small cohort; however, there were many complications.     

Total knee replacement in previous recipients of fresh osteochondral allograft transplants

BACKGROUND: Fresh osteochondral allograft transplantation is a treatment option for young patients with osteochondral lesions of the knee. The present study evaluated the surgical complexity of, and the prevalence of complications related to, total knee arthroplasty in patients who had had a previous osteochondral graft transplantation. METHODS: A retrospective analysis was performed on thirty-three consecutive patients (thirty-five knees) who underwent total knee arthroplasty from 1974 to 2000 after having had a previous transplantation of a fresh osteochondral allograft into the same knee. The mean duration of follow-up was ninety-two months. Perioperative data were analyzed with regard to etiology, preoperative impairment, intraoperative technical complications, early and late postoperative complications, and postoperative functional and subjective outcomes. The Knee Society clinical rating system was used for clinical evaluation beginning in 1990. RESULTS: Four knees required additional techniques for exposure. Three knees required stemmed components, one knee required a tibial augment, and two knees required morselized grafts. The mean Knee Society objective score (available for eighteen knees) improved from 34.7 preoperatively to 87.9 at the time of the latest follow-up, and the mean Knee Society function score improved from 45 to 82. The mean range of motion of all knees improved from 85 degrees to 105 degrees . Six of the thirty-five knees underwent revision total knee arthroplasty because of aseptic loosening, with two knees being revised within two years after the index total knee arthroplasty. CONCLUSIONS: Total knee arthroplasty after previous fresh osteochondral allograft transplantation provides improvements in knee function and range of motion, with manageable technical difficulties. Compared with routine total knee arthroplasty, an increased rate of early revision can be expected.     

Conversion of failed modern unicompartmental arthroplasty to total knee arthroplasty

Between January 1983 and January 1991, 29 patients (31 knees) with a failed Robert Brigham metal-backed knee arthroplasty (Johnson & Johnson, Raynham, MA) underwent revision to a total knee arthroplasty (TKA). Twenty-five patients had osteoarthritis, three avascular necrosis, and one rheumatoid arthritis. The average patient age was 72.3 years (range, 49–88 years), and the average weight was 179 lb. (range, 112–242 lb.). The interval between the primary and secondary index procedures averaged 62 months (range, 7–106 months), and mean postrevision follow-up period was 45 months (range, 24–104 months). The primary mechanism of failure of the UKA was tibial polyethylene wear in 21 knees and opposite compartment progression of arthritis in 10 knees. Sixteen knees had particulate synovitis with dense metallic staining of the synovium. At revision, the posterior cruciate ligament was spared in 30 knees and substituted in 1 knee. Restoration of bony deficiency at revision required cancellous bone—graft for contained defects in seven knees, tibial wedges in four knees, and femoral wedges in two knees. No defects received structural allografts. The data suggest that failed, modern unicompartmental knee arthroplasty can successfully be converted to TKA. In most cases, the posterior cruciate ligament can be spared and bone defects corrected with simple wedges or cancellous grafts. Moreover, the results of revision of failed unicompartmental knee arthroplasty are superior to those of failed TKA and failed high tibial osteotomy and comparable to the authors' results of primary TKA with similar-length follow-up periods. Although these results are encouraging, longer-term follow-up evaluation is required to determine survivorship of these revision arthroplasties.     

Posterior cruciate ligament-retaining total knee arthroplasty in patients with rheumatoid arthritis

BACKGROUND: Although initial reports on posterior cruciate ligament-retaining total knee arthroplasty in patients with rheumatoid arthritis have been encouraging, a high rate of late instability necessitating revision has been reported recently. The purpose of the present prospective study was to analyze the results of posterior cruciate ligament-retaining total knee arthroplasty in patients with rheumatoid arthritis. METHODS: Seventy-two posterior cruciate ligament-retaining total knee arthroplasties in fifty-one patients with rheumatoid arthritis were studied prospectively. All procedures were performed with the Miller-Galante I prosthesis. Eighteen patients (twenty-four knees) died before the eight-year follow-up and one patient (two knees) was lost to follow-up, leaving forty-six knees (thirty-two patients) for review. These forty-six knees were evaluated clinically (with particular attention to posterior instability) and radiographically at annual intervals for a mean of 10.5 years (range, eight to fourteen years). RESULTS: Forty-four (95%) of forty-six knees had a good or excellent result at a mean of 10.5 years. However, nine (13%) of the original seventy-two knees had revision of the implant, with six of the revisions performed because of failure of a metal-backed patellar component. The rate of survival at ten years was 93% 4% with femoral or tibial revision for any reason as the end point and 81% 5% with any reoperation as the end point. There was no aseptic loosening in any knee. Posterior instability was identified clinically and/or radiographically in two (2.8%) of the original seventy-two knees; both unstable knees were in the same patient. CONCLUSION: Posterior cruciate ligament-retaining total knee arthroplasty yielded satisfactory clinical and radiographic results in patients with rheumatoid arthritis at intermediate-term follow-up (mean, 10.5 years). Therefore, we believe that it remains an excellent treatment option for these patients.     

Patellar tendon bone grafting for patellectomized patients having total knee arthroplasty

A technique for restoring the moment arm to improve quadriceps leverage after patellectomy has been developed and used in patients treated with total knee arthroplasty. Essentials of the technique involve use of a 2.5-cm diameter by 1-cm thick bone graft sewn into the previous anatomical position of the patella, using a subsynovial pouch for stabilization. Clinically, seven knees in six patients were treated with patellar tendon bone grafting during total knee arthroplasty. The final outcome of these patients was evaluated from 24 to 125 months (mean, 75.4 months). Good to excellent results were demonstrated in six of seven knees (85.7%) with sufficient extension power for normal gait in most cases. Failure to achieve painless, active extension was seen in one patient following revision knee arthroplasty complicated by chronic reflex sympathetic dystrophy of the knee. Patellar tendon bone grafting improves quadriceps leverage in previously patellectomized knees and is useful in restoring extensor function in such patients having primary or revision knee arthroplasty.     

Total knee arthroplasty for osteonecrosis

BACKGROUND: A patient with collapse of a femoral condyle caused by osteonecrosis has few treatment options other than total knee arthroplasty. The purpose of this study was to report the clinical and radiographic outcome of total knee arthroplasty for osteonecrosis. METHODS: Between 1987 and 1996, thirty-two total knee arthroplasties were performed with cement in thirty patients with osteonecrosis of the femoral condyle and/or tibial plateau. The study group included twenty-forty women and five men with a mean age of fifty-four years (range, thirty-one to seventy-seven years) at the time of the arthroplasty. Twenty-two patients had atraumatic osteonecrosis associated with corticosteroid use, and eight had spontaneous osteonecrosis. All patients had a complete clinical and radiographic evaluation at a mean of 108 months (range, forty-eight to 144 months) postoperatively. RESULTS: Overall, thirty-one (97%) of the thirty-two knees had a successful clinical outcome. The mean Knee Society score improved from 54 points preoperatively to 95 points at the time of the latest follow-up. No evidence of progressive radiolucency was found around any prosthetic component. CONCLUSIONS: Previous studies have demonstrated less-than-optimal results following total knee arthroplasty in patients with osteonecrosis. The excellent results found in the present study may have been secondary to the use of cemented implants in all cases and ancillary stems when appropriate.     

Medial unicompartmental knee arthroplasty with the Miller-Galante prosthesis

BACKGROUND: Unicompartmental knee arthroplasty has become a popular treatment alternative for osteoarthritis that is confined to the medial part of the knee. Excellent intermediate-term results recently have been reported in association with the Miller-Galante unicompartmental implant. The purpose of the present study was to report on our longer-term experience with the Miller-Galante medial unicompartmental knee implant. METHODS: We evaluated the results of 113 medial unicompartmental knee arthroplasties that had been performed with use of the Miller-Galante implant in eighty-four patients between 1989 and 2000. The mean age of the patients at the time of surgery was sixty-eight years. Forty-five patients were men, and thirty-nine were women. Thirteen patients (sixteen knees) died at a mean of seven years after the index arthroplasty. No patient was lost to follow-up. The remaining seventy-one patients (ninety-seven knees) were followed for a mean of ten years and were evaluated with use of the Knee Society clinical and radiographic rating system. RESULTS: Eleven knees were revised at a mean of four years after the index procedure. The mean Knee Society knee and function scores for the sixty-one patients (eighty-six knees) who were living and who had not had a revision improved from 48 and 53 points preoperatively to 93 and 80 points at the time of the most recent evaluation. The five and ten-year rates of survival were 94% and 90%, respectively, with revision to tricompartmental knee arthroplasty as the end point and 93% and 86%, respectively, with revision or radiographic loosening as the end point. CONCLUSIONS: The Miller-Galante medial unicompartmental knee arthroplasty provided excellent pain relief and restoration of function in carefully selected patients and demonstrated durable implant survival at ten years.     

Revision total knee arthroplasty by impaction bone grafting

The presence of bone loss in a failed total knee arthroplasty can present a significant reconstructive challenge. Experience with the technique of using impacted morselized allograft with revision components having fixed stems is presented. Nineteen knees (21 patients) were reconstructed using impacted bone graft alone in 14 knees, bone graft plus methylmethacrylate in five knees (including one knee in which the replacement failed), and in three knees morselized bone graft was used in conjunction with structural bone allograft. Minimum followup ranged from 6 months to 62 months for the patients in the current series. These patients represent a relatively small, but growing portion of this surgeon's population of patients undergoing revision knee arthroplasty. Patients with large defects were selected for the study. Histologic specimens from the one failed knee arthroplasty revealed viable, incorporated bone graft. Excluding the replacement that failed, the average improvement in Knee Society combined knee and function scores was 87 points. The principles of revision and primary total joint arthroplasty are applied for achieving a stable implant. Specific to this technique, solid support of the implant-graft interface, graft-host bone interface, and the use of a tight, supportive stem is imperative. The author's experience provides additional support for the use of bone grafting techniques in patients with large bone defects who are undergoing revision total knee replacement.     

The results of tibial tubercle osteotomy for revision total knee arthroplasty

Tibial tubercle osteotomy was used in the surgical exposure of 67 knees in 64 patients undergoing revision total knee arthroplasty. The clinical and radiographic results were reviewed retrospectively. The mean follow-up time was 30 months (range, 5-60 months). Knee Society scores (KSS) confirmed good or excellent results in 87% of the knees, and the mean KSS was 86. The procedure was particularly effective in 2-stage exchanges for infected total knee arthroplasty, in which infection was eradicated in 9 of 10 cases, with a mean KSS of 82. In this series, no patellofemoral complications, no component malalignments, and no avulsions of the patellar tendon occurred. Serious complications directly related to the tibial tubercle osteotomy occurred in 5 patients (7%).