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PubMed1986

Total condylar knee prosthesis with posterior stability. A mid-term follow-up of 74 cases with severe deformity.

The midterm results of 74 posterior stability total condylar prostheses were studied (average follow-up 3 1/2 years). The average age of the patients was 65 years with a predilection for females (73%). The most frequent diagnosis was osteoarthritis (70%) followed by rheumatoid arthritis (28%): in 20% of the cases previous operations had been performed. Most of the patients had severe deformity which was not susceptible to other surgical treatment. The most frequent deformity was varus (average 13 degrees), followed by valgus (average 25 degrees), and flexion contracture (average 37 degrees). Bone defect in the tibia requiring surgical treatment were present in 18% of the cases. The most frequent general complication was pulmonary embolism (5%), which was never fatal; minor complications related to wound healing were observed in 17.5% of the cases. The results, evaluated with a numerical recording form devised by the Hospital for Special Surgery (New York) were: excellent 72%, good 21%, fair 4%, poor 3%. Of the 4 fair results, one had lateral laxity following lysis for valgus knee, one had loosening of the tibial component, and one had painful patellar clicks. Painless, small patellar clicks were observed in 4 other patients. The two poor results were due to low-grade infection and detachment of both components. Seventy per cent of the knees had normal or almost normal function with maximum flexion averaging 100 degrees. In 78% of the cases a study of the cement-bone interface revealed either no radiotranslucent line or present in only one area of the tibia. Radiotranslucent lines around the femoral or patellar component was rare and of no clinical significance.

Adult↗
PubMed1988

Fracture of the porous-coated metal tray of a biologically fixed knee prosthesis. Report of a case.

It has been assumed that, when properly implanted, a biologically fixed device is less prone to loosening and probably to fatigue failure as well. This case demonstrates that many of the known risk factors of loosening or fatigue fracture of cemented tibial replacement devices must be considered when using devices designed for biologic fixation. Age, weight, axial alignment, and bone substrate have been identified as probable contributing factors to failure in the case reported here. Manufacturing technique and changes in material properties associated with porous coating should also be carefully tested for factors predisposing the components to fatigue failure.

Adult↗
PubMedDate not supplied

[Results 2 to 5 years after implantation of the cement-free "APS" total knee prosthesis. A retrospective study of the first 160 cases].

One hundred-and-forty-seven out of 160 cementless APS total knees replacements have been clinically and radiologically evaluated with a mean follow-up period of 38 (24-60) months. Primary diagnosis has been osteoarthrosis in two thirds and rheumatoid arthritis in one. Reoperations have been performed in 4.9% due to aseptic loosening of the tibial tray, and in 3.7% due to patellar problems (aspetic loosening in 1.2% and luxation in 2.5%). There have been three late infections of the joint leading to arthrodesis in two or exchange operation in one case. The radiologic course of the remaining 126 implants showed excellent or good osseous integration of the implants in more than 80%. We were able to show that rheumatoid arthritis as well as malimplantation of the prosthesis can decrease the rate of osseous integration.

Adult↗
PubMed2000

Early catastrophic failure of rotating hinge total knee prosthesis.

The mechanical failure of a prosthesis component is usually observed as a late complication of total knee arthroplasty (TKA). In knees with severe ligament instability and bone deficiency, either a true hinge prosthesis or a rotating hinge implant is commonly used. Failure of the polyethylene bearing bush in a hinge-type prosthesis is a complication that has not been reported to date. We report the cases of 2 rotating hinge TKA prostheses that dislocated as a result of mechanical failure of the prosthetic component within 5 months of initial implantation. Clinicians should be aware of this potential complication when selecting rotating hinge prostheses for certain patients.

Arthroplasty, Replacement, Knee↗
PubMed2003

Brachytherapy tubes and free tissue transfer after soft tissue sarcoma resection.

Irradiation commonly is used after resection of soft tissue sarcomas to decrease the local recurrence rate. Brachytherapy spares more normal tissue than external beam irradiation and permits irradiation to the tumor bed in the immediate postoperative period. After vascular anastomosis and irradiation, flap survival can be affected by vascular coagulation in the immediate postoperative period and later by vascular fibrosis secondary to irradiation effects. The purpose of the current retrospective study was to evaluate the survival of free tissue transfer when combined with brachytherapy after resection of soft tissue sarcomas. Thirty-six patients had wide resection of extremity tumors, free flap coverage, and brachytherapy 5 days after surgery. Followup averaged 54 months. There were three major and four minor complications. The major complications included two patients with free flaps who required revision of anastomosis before radiation therapy (they had brachytherapy 5 days after the second surgery without additional complications) and one patient who had a deep wound infection develop 2 months after the index procedure and required a second flap. Minor complications included one hematoma, one partial skin graft loss, and two superficial infections. Brachytherapy can be done safely at the site of microvascular anastomosis in the immediate postoperative period.

Adolescent↗
PubMed2001

Acute synovitis, fever and rash possibly caused by metallic debris from a loosened knee prosthesis in a patient with rheumatoid arthritis.

A 39-year-old woman with long-standing seropositive rheumatoid arthritis who had a total replacement of her left knee with a modular prosthesis in 1994 presented with fever, pruritic rash, and acute synovitis of that joint following local trauma. Synovial fluid showed a charcoal-like color, and contained abundant phagocytes laden with metal particles. In patients with rheumatoid arthritis who have undergone total joint replacement, metal particle reactions and possible hyper-sensitivity should be added to the list of potential causes of superimposed acute synovitis and systemic manifestations.

Journal Article↗
PubMed2004

Mobile-bearing total knee prosthesis: a 5- to 9-year follow-up of the first 110 consecutive arthroplasties.

This study regards the total articulating cementless knee. This is a mobile-bearing knee, the tibial component of which consists of 2 parts: a highly conforming polyethylene insert freely rotating on a metal tray. Our case study relating to the implant of the first 110 knees operated on consecutively from 1991 to 1995 is reported, with an average follow-up of 6.3 years (range, 5-9 years). The average preoperative Knee Society Score was 78 points, and the average postoperative score was 156 points. The complications specifically related to the prosthetic components and which required revision surgery were 4: 2 cases of instability, 1 aseptic loosening of the tibial tray, and 1 traumatic dislocation of the tibial insert. A further 3 patients underwent reoperation for causes not strictly related to the implant: 2 because of intractable patellar pain and 1 because of periprosthetic ossifications that limited flexion. All of the complications were observed in patients operated on during the first 3 years of our experience, thus suggesting a definite learning curve with this prosthesis. No evidence of progressive radiographic periprosthetic osteolysis was recorded, and no relevant polyethylene wear was observed over time. Kaplan-Meier survival curves show the probability of survival to be 93.7% with revision surgery for any reason as an endpoint, and 96.3% with revision surgery for a mechanical reason as an endpoint. Certainty that mobile-bearing total knees are able to assure a longer life of the implant than the conventional models would require an evaluation of results over 15 to 20 years. However, in the meantime, these good preliminary results at least justify continuing the use of this type of prosthesis, which still awaits confirmation of the, as-yet-theoretical, advantage compared with fixed-bearing total knees.

Aged↗
PubMed1982

The Marmor knee prosthesis: long term results in 135 cases.

The authors report the results of clinical and radiological follow up examinations carried out between six months and four years after the insertion of Marmor knee prostheses in 135 patients (ninety-three with rheumatoid arthritis and forty-two with osteoarthrosis) operated on at the Orthopaedic Clinic of the University of Uppsala between 1975 and 1979. The results were very good and the few complications that arose were easily resolved. The authors have therefore adopted the Marmor prosthesis for routine use. The only valid alternative to this type of prosthesis is the spherocentric prosthesis, which was applied after failures with the Marmor or other types of prosthesis, in cases involving varus or valgus deformity exceeding 30 degrees, and in cases of severe bone destruction.

Adult↗
PubMed1998

[Patellar substitution in total knee prosthesis--is it important?].

As shown in long term follow-up studies of Total Knee Arthroplasty (TKA), the femoropatellar joint is an important problem. We report our experience over the past seven years not having resurfaced the patella at the primary TKA at all. Between 1990 and 1997 more than 700 consecutive TKA with the De Puy New Jersey LCS prosthesis were performed. A standardised lateral approach with osteotomy of the tibial tuberosity was used. The patella was redressed, either denervated or left untouched. In no case a primary patellar resurfacing was performed. X-rays of the patello-femoral joint showed a remodelling of the patella over the years, nicely matching the condylar design of the femoral prosthesis. Using a blood-supply-preserving approach and a biomechanically adequate implant, TKA without patellar replacement gives excellent long-term results.

Arthroplasty, Replacement, Knee↗
PubMedDate not supplied

[Significance of sagittal stability in knee prosthesis implantation--an analysis of 76 cases with unconstrained joint surface replacement].

ISSUE: How does the sagittal stability influence the outcome in unconstrained knee arthroplasty? METHOD: In order to clarify this aspect, 76 arthroplasties (10 male, 66 female, 39x gonarthrosis, 37x rheumatoid arthritis) in 61 patients with unconstrained primary knee arthroplasty were examined with a mean follow-up of 4 years. The determined values were the HSS-Score, the Knee-Society-Score, the range of motion, the flexion contracture as well as the posterior and anterior drawer with the KT 1000. The laxity was defined as the sum of the anterior and posterior drawer. RESULTS: The mean values measured were 2.9 mm for the anterior drawer, 1.9 mm for the posterior drawer and 4.8 mm for the laxity. The total patient population reached 81.3 points in the Knee Score, 70.9 points in the Function-Score and 80.7 points in the HSS-Score. The medium range of motion was determined as 103.5 degrees, the medium flexion contracture as 3.5 degrees. For an anterior drawer of > 6 mm and a posterior drawer of < 1 mm the results deteriorated significantly. A laxity of 8-11 mm gave the best score results. CONCLUSION: An anterior drawer of < 6 mm, a posterior drawer of 2-5 mm and a laxity of 8-11 mm seem to be recommendable for unconstrained knee arthroplasty.

Aged↗
PubMed2002

[Is there a correlation between clinical results or quality of life and radiological findings after implantation of a total knee prosthesis?].

AIM OF THE STUDY: To establish whether there is a clinical correlation between clinical outcome or quality of life and radiographic findings. MATERIAL AND METHODS: 17 patients (mean age 68.2 years) with total knee arthroplasty were examined after an average follow-up of 24.6 months. The examination included the HSS score for clinical parameters, and the SF-36 questionnaire quality of life. Radiographs were evaluated in accordance with Ewald and Lotke, and a schema of our own. RESULTS: The HSS score returned a mean of 81 points, and the SF-36 questionnaire showed significantly poorer results in comparison with age-matched healthy subjects. The Lotke evaluation of the X-rays showed a mean value of 76.3. Correlations between the radiographic findings and the HSS score were not seen. Correlations between X-ray parameters (Ewald and Lotke) and the SF-36 were found only for pain and vitality. CONCLUSIONS: This is the first study to investigate the correlation between clinical parameters (including quality of life) and X-ray findings. Neither the clinical score nor the quality of life score was found to correlate with the radiographic findings. Nor was more than minimal correlation found between quality of life and HSS score. These results show that the presence of radiolucent lines or deviations from the perfect prosthesis position must not necessarily be considered to be of importance for clinical outcome and quality of life.

Activities of Daily Living↗
PubMed1999

Results and complications of the low contact stress knee prosthesis.

We present the midterm results and complications of 101 low contact stress total knee replacements performed in 94 patients and reviewed at an average follow-up of 5.2 years (range, 4-8 years). The mean age at the time of surgery was 66 years (range, 53-76 years). Meniscal bearings were used in 83 knees and a rotating platform in the remaining 18 cases; cemented fixation was used only for 16 tibial components. At most recent follow-up, average knee and function scores were 93 and 78 points. None of the knees was revised because of loosening. Five knees showed distal femoral stress shielding. Complications included infection, supracondylar fracture, patellar component dislodgment, meniscal dislocation (2 cases), catastrophic wear of polyethylene, and progressive osteolysis (2 cases).

Aged↗
PubMed2001

[Mobility outcome after knee prosthesis implantation and subsequent physical therapy--factors influencing rate of success].

Osteoarthritis of the knee is considered to be the most common degenerative joint disease and finally ends up in a total knee replacement. Pain relief, restoration of a passive knee stability and improvement of functional ability are the primary goals of arthroplasties. But at the surgeons' closing, the patient for the present has just a knee "ready to function". Making the new joint function and recovering quality of life are the major outcome criteria for the rehabilitation process. This retrospective research was performed to evaluate three different rehabilitation programmes provided for patients receiving knee arthroplasties. Included were 124 patients with unilateral knee arthroplasty due to primary gonarthritis. All three rehabilitation clinics were able to improve the functional ability of the affected joints significantly, without any quantitative differences among them. The main influence factor in reaching the therapy aim (defined as: full extension and flexion > or = 90 degrees) seems to be the length of stay in the rehab clinic, which in turn is dependent on the presence of complications. On the other hand complications did not directly affect the achievement of the rehab goal, neither did age of patients, number of days between discharge (from acute care) and admission (to the rehab clinic), nor any accompanying illnesses. There, hence, have to be additional factors which influence the length of stay and so indirectly the rehab aim, factors which obviously are not accessible to quantitative objective measuring methods.

Aged↗
PubMed2000

Results of a single total knee prosthesis compared with multiple joint replacement in the lower limb.

We present the clinical results of total knee replacement (TKR) in 133 patients who had two or more major joints of the lower limbs replaced, and compare them to the outcome in 406 patients with an isolated TKR. 383 patients had osteoarthritis (OA) and 136 had rheumatoid arthritis (RA) and these were assessed separately. A meniscal bearing prosthesis was used. The functional score was high and there was no statistically significant difference in the incidence of complications between the two groups.

Aged↗
PubMed1995

[Uncemented knee prosthesis. Results apropos of 58 cases with a minimum of 5-year follow-up].

PURPOSE OF THE STUDY: The aim of this study was to evaluate, after at least 5 year's follow-up, the results of 64 PCA (TM) cementless total knee prostheses. MATERIAL: From 1984 to 1988, 13 male and 45 female patients (a total of 64 prostheses including 6 bilateral) received PCA Primary prostheses. Both femoral and tibial components were implanted without cement. Mean age of patients was 68.9 years (range: 35-81); mean patient height was 164.41 cm and mean weight 76.74 Kg. The most frequent pathology was gonarthrosis: 43 cases of medial gonarthrosis and 15 of lateral gonarthrosis. There were 4 cases of rheumatoid arthritis and two post-traumatic degenerative arthritis. 52 knees were free of any previous surgical procedure. Of the 64 prostheses and the 58 patients: 6 died and 2 were lost to follow-up; 56 knees were reviewed. The longest follow-up is 9 years for an average of 6.8 years. METHODS: Prosthetic review included clinical evaluation (Hungerford score based on 100 points, ISK rate based on 200 points) and complete radiological evaluation enabling the postoperative position of the implants to be examined. Radiolucencies were examined according to Ewald. X-ray study of polyethylene wear was performed based on the distance between the prosthetic condyle to the height of the metal tibial plateau. All patients were operated on by the same surgeon using the same procedure, and the same postoperative outcome. RESULTS: There were no local postoperative complications or any early reoperations. PHlebitis occurred in 12 per cent of cases. With the exception of 8 patients who were reoperated due to mechanical complications, the Hungerford score raised from 37.5 preoperatively to 88.3 postoperatively. The results of 43 of the 48 patients were rated good or excellent. The 200 point score rating gave 91 per cent of good and excellent results for knee examination, and 69 per cent of good and excellent results for knee function. Mean flexion angle was 107.8 degrees mean pain scored 45/50. Radiologically 75 per cent of operated patients had postoperative varus or valgus in the range 0-5 degrees as against 24 per cent preoperatively. The study of edge defects revealed the absence of any radiological abnormality on the femoral lateral projection in 85 per cent of cases, and the absence of abnormality on the tibial anteroposterior and lateral projections in more than 60 per cent of cases. X-ray study of polyethylene wear was conducted on 49 cases: polyethylene wear was observed radiologically in 1 of 4 cases. There was no correlation between polyethylene wear and polyethylene thickness, postoperative axes, body weight or clinical results. 8 patients had to be reoperated due to mechanical complications: 2 because of a tilting tibial plateau (due to a technical fault), 4 because of polyethylene wear and 2 because of patellar loosening (uncemented metal-back patellar implant). DISCUSSION: The implantation of femoral and tibial components of cementless PCA Primary fitted seems very satisfactory. With longer follow-up, we noted no tibial or femoral osteolysis signs such as those described by Engh, Peters or Berry in the USA. Stability of mid term radiographical results was commonly observed throughout our study. Only 5 very slight lateral displacements were noted: 3 cases of secondary LCP insufficiency with tibial posterior subluxation; in 2 cases the cause was R.A. CONCLUSION: The implantation of uncemented PCA Primary prosthesis caused non complications with respect to the femur. Regarding the tibia, only two reoperations were required because of tibial fixation failure due to a technical fault. The use of a hybrid prosthesis is not required. The microbeads used in PCA are effective but current availability of other materials promoting better bone growth (such as hydroxyapatite, titanium mesh) allows safe implantation of uncemented prostheses. PCA Primary polyethylene wear seems to develop steadily. This is why it should be replaced by the less

Adult↗