The total condylar prosthesis. 10- to 12-year results of a cemented knee replacement

Over a two-year period 104 patients had 130 knee arthroplasties performed with the total condylar prosthesis at the Hospital for Special Surgery. At a 10- to 12-year review 58 patients (74 knees) had survived and were available for detailed clinical and radiographic evaluation. Of these, 38 knees (51.3%) were rated as excellent and 27 (36.5%) good. There were three (4.0%) fair and six (8.2%) poor results. Five of the six had had revision operations. The success of this early pattern of prosthesis supports the continued use of methacrylate cement for knee arthroplasties.     

The press-fit condylar modular total knee system with a posterior cruciate-substituting design. A concise follow-up of a previous report

The purpose of the present study was to determine the long-term results of a series of 150 consecutive primary posterior stabilized modular knee arthroplasties that had been performed in 118 patients with use of a circumferential tibial insert capture as described in a previous report, published in 1997. The patients were evaluated with use of a patient-administered questionnaire; Knee Society clinical, functional, and radiographic scoring systems; and Kaplan-Meier survivorship analysis. A good to excellent result was confirmed in seventy-six (90%) of the eighty-four patients (105 knees) with a mean duration of follow-up of twelve years (range, ten to thirteen years). At twelve years, the survival rate was 94.6% +/- 4.0% with failure for any reason as the end point and 98.3% +/- 2.4% with mechanical failure as the end point. Revision surgery was performed in five knees because of infection (two knees), dislocation (one knee), and substantial polyethylene wear with femoral osteolysis (two knees). We concluded that, while fixation failure is rare, polyethylene wear and osteolysis are emerging as important causes of failure.     

In vivo comparison of femorotibial contact positions for press-fit posterior stabilized and posterior cruciate-retaining total knee arthroplasties

The objective of this study was to determine the in vivo medial and lateral femorotibial condyle contact positions for 20 subjects having either a posterior cruciate-retaining (PCR) or posterior-stabilized (PS) total knee arthroplasty (TKA) while sitting and kneeling. The two-dimensional radiographic images were converted into three-dimensional images using an iterative computer model-fitting technique. Anteroposterior contact positions, axial rotation, and condylar lift-off were assessed for each subject. In a seated position, the femorotibial contact points were, on average, posterior for both TKA groups (PCR: medial = -2.4 mm, lateral = -3.4 mm; PS: medial = -5.1 mm, lateral = -8.9 mm; medial, P=.21; lateral, P=.08). In a kneeling position, the contact position shifted anteriorly for the PCR TKA group (medial = 0.9 mm, lateral = -0.8 mm), whereas the contact positions in the PS TKA group remained posterior (medial = -5.6 mm, lateral = -8.3 mm; medial, P=.002; lateral, P=.0004). It is hypothesized that while in a kneeling position, the posterior cruciate ligament has less resistance to the anterior thrust of the femur relative to the tibia than in a PS TKA, in which this force is absorbed in the cam-and-post mechanism.     

Posterior cruciate-retaining modular total knee arthroplasty: a 9- to 12-year follow-up investigation

Between November 1988 and January 1991, 101 press-fit condylar (PFC; Johnson & Johnson, Raynham, MA) posterior cruciate-retaining total knee arthroplasties were performed in 75 patients. All tibial components were modular metal-backed, and all patellar components were all-polyethylene. All living patients were evaluated at an average 10.5 years (range, 9.5-11.8 years). Only 1 knee required revision (at 11.1 years after the procedure), and only 1 other knee had evidence of radiographic failure. The average range of motion was 1 degrees (range, 0 degrees -10 degrees ) to 110 degrees (range, 86 degrees -130 degrees ). At 10 years of follow-up, the probability of prosthesis survival was 100%, and at 12 years, the probability of prosthesis survival was 93.3% (endpoint defined as revision for any reason).     

Resurfacing versus not resurfacing the patella in total knee arthroplasty: 8- to 10-year results

Patellar resurfacing in total knee arthroplasty is a topic debated in the literature. Concerns include fracture, dislocation, loosening, and extensor mechanism injury. Residual anterior knee pain has been reported when the patella is not resurfaced. One hundred patients with osteoarthritic knees were prospectively randomized to either have their patella resurfaced or left not resurfaced. All patients were treated with a single prosthesis that featured an anatomically designed patellofemoral articulation (Anatomic Medullary Knee, DePuy, Warsaw, IN) Two patients in the unresurfaced group and one in the resurfaced group required repeat surgery for patellofemoral complications. At 8- to 10-year follow-up evaluations, Knee Society Clinical Ratings scores were not different between the 2 groups. Rates of anterior knee pain with walking and stair climbing were significantly less in the resurfaced group. Eighty percent of patients with a resurfaced patella were extremely satisfied with their total knee arthroplasty versus 48% without patellar resurfacing. When satisfied and extremely satisfied patients were grouped together, there was no difference between the 2 groups.     

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

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.     

Twelve years' experience with posterior cruciate-retaining total knee arthroplasty

The posterior cruciate ligament can be retained with advantage during routine total knee arthroplasty. This ligament is virtually always intact and functioning, even in rheumatoid patients. It is an important biologic stabilizer of the knee, capable of absorbing anterior-posterior shearing forces that otherwise must be borne by a constrained prosthesis and hence by the bone-cement interface. Its presence allows maintenance of the normal kinematics of the knee. Roll-back of the femur on the tibia can occur, enhancing flexion and improving the quadriceps moment. Substitution of the posterior cruciate ligament with the addition of prosthetic constraint will increase bone-cement reaction forces. These prostheses also require significant intercondylar femoral bone stock resection. The average range of motion of the early cruciate sacrificing design used in Insall's series was 94 degrees, 10 degrees or more less than now routinely seen with cruciate preservation. The bone-cement interface of the early total condylar knee with limited range of motion absorbed less force than it potentially might encounter with greater range of motion and increased function. Predictably, at long-term follow-up examination the newer cruciate-substituting prostheses that allow more physiologic range of motion might show higher radiolucent line rates and higher loosening rates than their cruciate-preserving counterparts. Only this information can settle the argument over whether the posterior cruciate ligament should be preserved, and if the objective is a knee with maximum flexion and maximum functional capability.     

Loosening and osteolysis with the press-fit condylar posterior-cruciate-substituting total knee replacement

BACKGROUND: Aseptic loosening and osteolysis are rarely associated with cemented posterior-cruciate-substituting total knee replacements. Consequently, there is a paucity of information on this topic. METHODS: After a mean follow-up interval of fifty-six months (range, thirty-seven to eighty-nine months), sixteen (2.9%) of 557 posterior-cruciate-substituting primary total knee replacements were revised by a single surgeon because of loosening and osteolysis. Clinical, radiographic, and retrieval analyses were conducted to determine the mechanism of loosening and to identify associated risk factors. RESULTS: All sixteen knees (fifteen patients) were rated as good or excellent at one year after the primary replacement, with mean clinical and functional Knee Society scores of 95 and 86 points, respectively. Nine of the fifteen patients who had a revision because of loosening and osteolysis had had a total knee arthroplasty on the contralateral side compared with only 18% of the patients who did not have a revision (p = 0.026). No evidence of transmission of substantial anteroposterior stresses from the posterior-cruciate-substituting mechanism was found. All twelve retrieved knee implants, however, had damage to the lateral and medial side walls of the polyethylene posterior-cruciate-substituting post. Damage to the inferior surface of the polyethylene inserts had a rotational pattern, with the axis of rotation in the medial compartment. Surface damage in a rotational pattern was also present on the superior and inferior surfaces of the titanium tibial base-plates. CONCLUSIONS: In the knees in our study, rotational forces were generated by impingement of the side walls of the intercondylar box on the polyethylene post. Such box-post impingement can occur throughout the range of motion. Rotational stresses are transmitted to the modular interfaces and to the metal-cement interfaces, resulting in loosening and osteolysis. A reduction in rotational constraint would be desirable. Patients with bilateral total knee replacement may be at increased risk for this type of loosening.     

Press-fit condylar total knee arthroplasty: 5- to 9-year follow-up evaluation

Between November 1984 and December 1987, 378 consecutive Press-Fit Condylar (PFC, Johnson & Johnson Professional, Raynham, MA) total knee arthroplasties were performed in 290 patients. The average age at surgery was 67 years (range, 22–91 years). The average follow-up period was 6.5 years (range, 5–9 years). Scoring was carried out according to the Knee Society scoring system. The average preoperative knee score was 28, and the average postoperative knee score was 88. The average preoperative functional knee score was 49, and the average postoperative functional knee score was 72. Ninety-five percent of the patients had no pain on level walking and were satisfied with their functional result. The average postoperative knee flexion was 110°. No implant showed any evidence of radiographic loosening. There were 17 complications, all requiring reoperation. Complications included excessive wear of a metal-backed patella in 8 knees. If complications resulting from the earlier use of a metal-backed patella are eliminated, the overall complication rate is 2.9%, which is comparable to or lower than the rates for other total knee systems with similar follow-up periods.     

Long-term results of cruciate-retaining total knee replacement in patients with rheumatoid arthritis: a minimum 15-year review

Background

There is controversy about whether to retain or excise the posterior cruciate ligament in rheumatoid knees because attenuation of the ligament is often present in this subgroup of patients. We reviewed more than 15 years of results of cruciate-retaining total knee replacements (TKRs) in patients with rheumatoid arthritis.

Methods

We reviewed patients’ charts and radiographs to evaluate knee range of motion and flexion contractures, component loosening and osteolysis at the bone–cement interface. Our primary outcome was revision of a femoral or tibial component for any reason, and the secondary outcome was revision for any reason and periprosthetic fracture during the follow-up period.

Results

Our study included 112 patients (7 men, 105 women, 176 knees). Their mean age was 49.3 (range 33–64) years. Twenty-one patients died and 16 were lost to follow-up, leaving 75 patients (119 knees) with a minimum follow-up of 15 (mean 16.1) years for our analysis. Of these, 61 patients (101 knees) were available for clinical and radiological evaluation at the final follow-up assessment. At a mean of 12.2 (range 6–16) years, revision was necessary in 14 patients (19 knees), including 1 patient with an infection. Eleven patients (11 knees) had periprosthetic fractures at a mean of 11.4 (range 5–14) years after the index operation. The survival rate, with the end point being revision of the femoral or tibial component for any reason, was 98.7% at 10 years and 83.6% at 17 years. The survival rate of revision and periprosthetic fracture was 97.6% at 10 years and 76.9% at 17 years.

Conclusion

Special attention should be paid to component loosening or periprosthetic fracture after more than 10 years of follow-up in this subgroup of patients.     

后交叉韧带保留型和后稳定型全膝关节置换术后早期临床疗效比较

目的评价后交叉韧带保留（PCR）型和后稳定（PS）型全膝关节置换（TKA）的早期临床疗效，探讨两种不同假体置换术的临床相关问题。方法回顾2000年4月～2005年10月139例（166膝）初次行TKA的患者资料，比较PCR型（PCR组）58例（69膝）和PS型（PS组）81例（97膝）的早期疗效，结合文献分析两种不同假体的优缺点及相关技术问题。结果术后随访1年，患者对手术的满意率PCR组为94.2％，PS组为93．8％，两组比较差异无统计学意义（P〉0．05）。HSS评分PCR组平均为93．9分，PS组平均为94．3分，两组比较差异无统计学意义（P〉0．05）。膝关节活动度PCR组平均为105．8°，PS组平均为107．4°，两组比较差异无统计学意义（P〉0．05）。患者主诉患膝有轻微疼痛者，PCR组有7膝（占10．1％），PS组有10膝（占10，3％），均不需特殊治疗。有明显髌骨弹响征者PCR组2例，PS组4例，但对功能活动无影响。结论PCR型或PS型TKA后早期随访疗效满意；对膝关节畸形较轻，术中探查后交叉韧带结构完整者，可考虑采用PCR型假体，但应松解PCR，原则上宁松勿紧；对于PS型假体，手术技术要求相对较低，容易掌握，临床适用范围更广。     

An 8- to 10-year review of the Rotaglide total knee replacement

Mobile-bearing knee arthroplasty (MBKA) is an alternative to fixed-bearing knee arthroplasty. This was a retrospective study of the Rotaglide Total Knee System. We present the results of the monitoring of 77 patients (85 knees) with a median duration to failure or end of follow up of 8.5 years (range 0.4 to 10.1 years). Patients were clinically and radiologically assessed at dedicated follow up clinics. The Hospital for Special Surgery (HSS) and Knee Society Score (KSS) systems were used to describe the clinical and radiological findings. The prosthesis had an estimated survival probability of 93.5% (standard error 3.4%) at 9 years. It is associated with good rates of patient satisfaction and high scores on the HSS and KSS systems. No knees were revised for aseptic loosening. This knee replacement has a survival rate equivalent to other prostheses. It is a safe and reliable prosthesis associated with good clinical outcome.     

Five- to 8-year results of the uncemented Duracon total knee arthroplasty system

We report prospective clinical and radiographic outcomes of a series of 219 hydroxyapatite-coated Duracon (Stryker Howmedica Osteonics Corporation, Kalamazoo, Mich) total knee arthroplasties with a follow-up of 5 to 8 years. Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis index (WOMAC), and SF-12 Health Status Questionnaire were used. Analysis of fluoroscopic radiographs was performed with the American Knee Society Score. All living patients (186 knees) were followed up. Twenty-eight patients (30 knees) had died. The preoperative Knee Society Score of 43.8 increased to 77.1 and the preoperative Function score of 20.3 increased to 63.4. WOMAC scores showed marked improvement (pain, 250 preoperatively to 157; stiffness, 115 preoperatively to 56; and function, 910 preoperatively to 588). There was no radiographic evidence of loosening or migration. Gaps visible at the bone-implant interface healed over the first year. Three prostheses were revised, 2 for deep infection and 1 for tibial tray subsidence. A survivorship of 98.6% has been achieved at 8 years. This intermediate-term study with 100% follow-up at 8 years demonstrates excellent clinical and radiographic outcomes. It is our opinion that these are comparable to the gold standard cemented total knee arthroplasties and may have advantages over other uncoated cementless designs.     

Long-term results of Alpina Postero-stabilized total knee replacement: 10- to 16-year follow-up

One hundred and ninety-four primary knee arthroplasties were done between 1992 and 1998 with Alpina Postero-Stabilized prosthesis. Eighty-eight knees were available for the long-term follow-up at a mean of 12?years. The mean IKS score improved from 103.1?±?21.9 points preoperatively to 161.5?±?25.6 at the latest follow-up (P?<?0.001). Eighty-four percent of the knees were rated good and excellent. The mean flexion significantly improved from 110° preoperatively to 117.5° at the latest follow-up (P?<?0.001). Two knees were revised: 1 due to infection and 1 due to femorotibial malalignment. Eight other knees were revised: 7 for isolated patella addition, 1 for patella replacement. Excluding patella failure, the 12-year Kaplan-Meier survivorship for the entire cohort was 98.8 (95% CI, 97.2–100%). Alpina Postero-Stabilized TKA showed good long-term results.     

Patellofemoral functional results and complications with the posterior stabilized total condylar knee prosthesis

The authors reviewed 73 knee arthoplasties performed with the Posterior Stabilized Total Condylar prosthesis, with an average follow-up period of 5.5 years. The function of the patellofemoral articulation was specifically analyzed. Patients with documented or suspected tibiofemoral problems were excluded. Using the Hospital for Special Surgery knee rating system, 48 knees (66%) had excellent, 20 had good (27%), and 5 (7%) had fair results. Patients with unilateral disease were able to negotiate stairs and transfer normally in 64% and 100% of the cases, respectively. The most frequent patellofemoral problem was impingement (21%), but reoperation was needed in only one patient. Stress fracture of the patella and subluxation were rare. A medial tilt of the patella on the axial view had no apparent ill effect. The patella was lowered 12 mm on average as a consequence of the standard bone resection sequence and insertion of the tibial component. The patella was significantly lower in patients with impingement than in normal joints. Routine complete patellofemoral resurfacing is advised in total knee joint arthroplasty. Complications are infrequent with appropriate prosthetic design and due technical care.     

A randomised controlled trial of cemented versus cementless press-fit condylar total knee replacement: 15-year survival analysis

We report the long-term survival of a prospective randomised consecutive series of 501 primary knee replacements using the press-fit condylar posterior cruciate ligament-retaining prosthesis. Patients received either cemented (219 patients, 277 implants) or cementless (177 patients, 224 implants) fixation. Altogether, 44 of 501 knees (8.8%) underwent revision surgery (24 cemented vs 20 cementless). For cemented knees the 15-year survival rate was 80.7% (95% confidence interval (CI) 71.5 to 87.4) and for cementless knees it was 75.3% (95% CI 63.5 to 84.3). There was no significant difference between the two groups (cemented vs cementless; hazard ratio (HR) 0.83, 95% CI 0.45 to 1.52, p = 0.55). When comparing the covariates there was no significant difference in the rates of survival between the side of operation (HR 0.58, p = 0.07), age (HR 0.97, p = 0.10) and diagnosis (HR 1.25 p = 0.72). However, there was a significant gender difference, with males having a higher failure rate with cemented fixation (HR 2.48, p = 0.004). Females had a similar failure rate in both groups. This single-surgeon series, with no loss to follow-up, provides reliable data of the revision rates of one of the most commonly-used total knee replacements. The survival of the press-fit condylar total knee replacement remained good at 15 years, irrespective of the method of fixation.     

Mid-term results of an AGC total knee arthroplasty system survival and function analysis: 2- to 8-year follow-up results

Between 1993 and 1999, 148 total knee arthroplasties were performed in Dipreca Hospital; 94 were anatomically graduated components (AGC) cam-and-groove posterior-stabilized total knee arthroplasties. All patients underwent implantation with a cemented posterior cruciate-substituting design, with resurfacing of 3 components. Mean age at surgery was 69 years, and patients were followed up for a minimum of 2 years (range, 2-8). The survival analysis at 8 years was 96.6%. Revision for any reason was considered to be the endpoint. Of patients, 3.2% were lost to follow-up. The mean knee pain and function scores were 89 and 64 of 100, respectively. The scores were also analyzed by categories. This knee arthroplasty follow-up analysis shows excellent midterm results.     

Total condylar knee arthroplasty. 16- to 21-year results.

This study presents long term results of arthroplasty with posterior cruciate retention using the Total Condylar Knee implant. From 1976 to 1982, 139 patients had 159 knee arthroplasties using Total Condylar Knee prostheses. Sixty-three patients (72 knees) were available for followup at a minimum of 16 years (range, 16-21 years). The average age of the patients at the time of surgery was 61 years. There were 21 men and 42 women. Patients with 68 knees had osteoarthrosis, three had rheumatoid arthritis and one had posttraumatic arthritis. There were five delayed complications. One patient (one knee) underwent revision surgery and two patients (two knees) declined revision surgery because they were considered to be high surgical risks, as determined by their internists. The average preoperative score was 40.3 points and improved to 88.4 points at followup. Eighty-seven percent of the patients had a score equal to or more than 85 points at last evaluation. Prosthesis survivorship at 20 years was 98.6% for patients who had revision surgery. No femoral components were revised for aseptic loosening. Retention of the posterior cruciate in Total Condylar Knee prosthesis produces results comparable with the results of the original Total Condylar Knee prosthesis with cruciate sacrifice.