https://www.just.edu.jo/DIC/ClinicGuidlines/Management%20of%20hip%20and%20knee%20Osteoarthritis.pdf

OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines

Background The efficacy of arthroscopic surgery for the treatment of osteoarthritis of the knee is unknown. Methods We conducted a single-center, randomized, controlled trial of arthroscopic surgery in patients with moderate-to-severe osteoarthritis of the knee. Patients were randomly assigned to surgical lavage and arthroscopic debridement together with optimized physical and medical therapy or to treatment with physical and medical therapy alone. The primary outcome was the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (range, 0 to 2400; higher scores indicate more severe symptoms) at 2 years of follow-up. Secondary outcomes included the Short Form-36 (SF-36) Physical Component Summary score (range, 0 to 100; higher scores indicate better quality of life). Results Of the 92 patients assigned to surgery, 6 did not undergo surgery. Of the 86 patients assigned to control treatment, all received only physical and medical therapy. After 2 years, the mean (±SD) WOMAC score for the surgery group was 874±624, as compared with 897±583 for the control group (absolute difference [surgery-group score minus control-group score], −23±605; 95% confidence interval [CI], −208 to 161; P = 0.22 after adjustment for baseline score and grade of severity). The SF-36 Physical Component Summary scores were 37.0±11.4 and 37.2±10.6, respectively (absolute difference, −0.2±11.1; 95% CI, −3.6 to 3.2; P = 0.93). Analyses of WOMAC scores at interim visits and other secondary outcomes also failed to show superiority of surgery.

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A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the Knee

These guidelines are intended for use by infectious disease specialists, orthopedists, and other healthcare professionals who care for patients with prosthetic joint infection (PJI). They include evidence-based and opinion-based recommendations for the diagnosis and management of patients with PJI treated with debridement and retention of the prosthesis, resection arthroplasty with or without subsequent staged reimplantation, 1-stage reimplantation, and amputation.

/pdf/diagnosis-and-management-of-prosthetic-joint-infection-4ogdeimcv4.pdf

Diagnosis and Management of Prosthetic Joint Infection: Clinical Practice Guidelines by the Infectious Diseases Society of America

The incidence of failure after knee replacement is low, yet it has been reported that more than 22,000 knee replacements are revised yearly. The purpose of the current study was to determine current mechanisms of failure of total knee arthroplasties. A retrospective review was done on all patients who had revision total knee arthroplasty during a 3-year period (September 1997-October 2000) at one institution. The preoperative evaluation in conjunction with radiographs, laboratory data, and intraoperative findings were used to determine causes of failure. Two hundred twelve surgeries were done on 203 patients (nine patients had bilateral surgeries). The reasons for failure listed in order of prevalence among the patients in this study include polyethylene wear, aseptic loosening, instability, infection, arthrofibrosis, malalignment or malposition, deficient extensor mechanism, avascular necrosis in the patella, periprosthetic fracture, and isolated patellar resurfacing. The cases reviewed included patients who had revision surgery within 9 days to 28 years (average, 3.7 years) after the previous surgery. More than half of the revisions in this group of patients were done less than 2 years after the index operation. Fifty percent of early revision total knee arthroplasties in this series were related to instability, malalignment or malposition, and failure of fixation.

Why are total knee arthroplasties failing today

Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided.

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Prosthetic Joint Infection

Infection following total joint replacement remains a major problem that has not been solved during the last thirty years. The prevalence of infection at the Mayo Clinic between 1969 and 1996 was 1.7 per cent of 30,680 total hip arthroplasties and 2.5 per cent of 18,749 total knee arthroplasties. After primary operations, the rate of infection was 1.3 per cent of 23,519 hips and 2.0 per cent of 16,035 knees. After revision operations, the rate was 3.2 per cent of 7161 hips and 5.6 per cent of 2714 knees (Table I). The rate of infection has been remarkably constant despite the use of different regimens of antibiotic prophylaxis, operating-room configurations, operative techniques, and modes of fixation of the implant. Factors leading to deep infection must be considered with respect to the host, wound, operative technique, operating-room environment, and microbiological characteristics of the infecting organisms. A prompt diagnosis of infection will facilitate treatment and minimize morbidity.

View this table:

TABLE I PREVALENCE OF INFECTION AFTER TOTAL JOINT ARTHROPLASTY FOR THE YEARS 1969 THROUGH 1996



As stated, in discussing the etiology of infection, the host, wound, operating-room environment, operative technique, and microbiological characteristics of the infecting organisms must be considered. The patient as host is an important risk factor for infection. The operative wound is contaminated to some extent in all procedures, but the immune-defense mechanisms of the host prevent infection in most instances. Immunocompromised patients are clearly at increased risk for deep infection as are patients who have rheumatoid arthritis110,140. In a series of 4171 total knee replacements, an infection developed after sixteen (0.9 per cent) of 1854 replacements in patients who had osteoarthrosis compared with forty-five (2.2 per cent) of 2076 replacements in those who had rheumatoid arthritis140. In a series of 4240 total hip, knee, and …

Evaluation and treatment of infection at the site of a total hip or knee arthroplasty.

Background: Failure of total knee arthroplasty is problematic. The purpose of this study was to evaluate the factors that influence the durability of a primary total knee prosthesis.

Methods: A survivorship analysis of 11,606 primary total knee arthroplasties carried out between January 1, 1978, and December 31, 2000, was performed. An analysis of patient and implant-related factors affecting survivorship was done with use of a multivariate Cox model.

Results: The survivorship was 91% (95% confidence interval, 90% to 91%) at ten years (2943 knees), 84% (95% confidence interval, 82% to 86%) at fifteen years (595 knees), and 78% (95% confidence interval, 74% to 81%) at twenty years (104 knees) following the surgery. Prosthetic survivorship at ten years was 83% for patients fifty-five years of age or less compared with 94% for those older than seventy years of age (p < 0.0001), 90% for those with a diagnosis of osteoarthritis compared with 95% for those with inflammatory arthritis (p < 0.005), and 91% for those with retention of the posterior cruciate ligament compared with 76% for those with substitution of the posterior cruciate ligament (a posterior stabilized prosthesis) (p < 0.0001). Survivorship at ten years was 92% for nonmodular metal-backed tibial components, 90% for modular metal-backed tibial components, and 97% for all-polyethylene tibial components (p < 0.0001). Survivorship at ten years was 92% for prostheses fixed with cement compared with 61% for those fixed without cement (p < 0.0001).

Conclusions: Significant risk factors for failure of total knee arthroplasty were the type of implant, age and gender of the patient, diagnosis, type of fixation, and design of the patellar component. In the ideal situation—treatment of a woman over the age of seventy years who has inflammatory arthritis with a nonmodular, metal-backed tibial component, cement fixation, an all-polyethylene patellar component, and retention of the posterior cruciate ligament—the ten-year survivorship of the prosthesis was estimated to be 98% (95% confidence interval, 97% to 99%).

Level of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.

Factors Affecting the Durability of Primary Total Knee Prostheses

From 1971 through 1987, 9200 total knee arthroplasties were performed at the Mayo Clinic. Actuarial analysis was used to estimate cumulative rates of survival. Use of a proportional-hazard, general linear model led to the identification of four independent variables that were associated with a significantly lower risk of failure: primary total knee arthroplasty, a diagnosis of rheumatoid arthritis, an age of sixty years or more, and use of a condylar prosthesis with a metal-backed tibial component. When all four of these favorable variables were present (without regard for radiographic changes and non-disabling symptoms), the probability of an implant being in situ was 97 per cent at both five and ten years.

Survivorship analysis of total knee arthroplasty. Cumulative rates of survival of 9200 total knee arthroplasties.

One hundred ninety-three geometric total knee arthroplasties (TKA) were performed between 1972 and 1975 in 129 patients (66 women, 63 men; mean age, 69 years) with osteoarthritis. Of these, 102 knees were followed for a mean of 11 years. Eighty-three percent of the patients had mild or no pain. The

Ten-Year Evaluation of Geometric Total Knee Arthroplasty

Of 168 consecutive knees (118 patients) that had been treated with an arthroplasty with use of a kinematic total condylar prosthesis that allowed retention of the posterior cruciate ligament, 119 knees (eighty-four patients) were available for review at a mean of 10.0 +/- 0.7 years after the operation. The Hospital for Special Surgery knee score improved significantly, from a mean of 55 +/- 12 points preoperatively to a mean of 81 +/- 9 points at ten years (p < 0.0001). Radiolucent lines about the patellar component, present in thirty-five of eighty-three knees at the latest follow-up examination, were related to malpositioning of the tibial and femoral components. Six revisions were performed, and four of them were for a loose patellar component. The rate of deep infection was 1 per cent (one knee). Complications occurred in twenty-six knees (22 per cent). With revision as the end point, the rate of survival of the prostheses was estimated to be 96 per cent at ten years. The knee scores, the rate of survival of the implants, and the range of motion of the knees in the current study were similar to those reported previously for patients who had insertion of a total condylar prosthesis with sacrifice of the posterior cruciate ligament and for those who had substitution of the posterior cruciate ligament with a posterior stabilized prosthesis. A prosthesis that has a metal-backed tibial component and that allows preservation of the posterior cruciate ligament provides durable results, but loosening of the patellar component remains a major problem.

James A. Rand

Papers

Evaluation and treatment of infection at the site of a total hip or knee arthroplasty.

Factors Affecting the Durability of Primary Total Knee Prostheses

Survivorship analysis of total knee arthroplasty. Cumulative rates of survival of 9200 total knee arthroplasties.

Ten-Year Evaluation of Geometric Total Knee Arthroplasty

Total knee arthroplasty with the kinematic condylar prosthesis. A ten-year follow-up study.