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PubMed1995

[Phenprocoumon-induced cholestatic hepatitis].

HISTORY AND CLINICAL FINDINGS: A 78-year-old woman had 4 years age received phenprocoumon as prophylaxis against thromboembolism after implantation of a left total knee prosthesis. Ten weeks later she developed hepatitis with negative hepatitis serology. 6 weeks before her latest hospitalisation a right total knee implantation had been performed and she again received phenprocoumon. She was admitted now because of cholestatic jaundice with rapid deterioration of her general state. There were no significant abnormal findings other than jaundiced skin and sclerae. INVESTIGATION: Bilirubin concentration was clearly elevated to 11.5 mg/dl, and the transaminase activities were increased, together with raised gamma-GT and alkaline phosphatase levels. The Quick value was below 8%. Hepatitis serology was positive for hepatitis A antibodies, but negative for B and C antibodies. No antigens were demonstrated. The eosinophil count was elevated in the differential blood count. Sonography showed a normal-sized liver with slightly dense echo pattern, but no evidence of abscess or dilatation of the bile duct system. Liver biopsy revealed severe acute hepatitis of viral type and discrete eosinophilic infiltration. TREATMENT AND COURSE: After all medication had been discontinued, transaminase activities decreased while bilirubin concentration rose. Thus, prednisone treatment was started (initially 50 mg/d), the dose then gradually reduced. The cholestasis parameters became normal and the patient's general state was much improved so that she could be discharged. CONCLUSION: Cholestatic hepatitis is a rare side effect of phenprocoumon. The associated eosinophilia suggests the cause to be an allergic genesis in the sense of a hypersensitivity reaction.

Aged↗
PubMed2005

Eversion or subluxation of patella in soft tissue balancing of total knee arthroplasty? Results of a cadaver experiment.

Correct postoperative leg alignment and stability of total knee prosthesis over the full range of movement are critical factors for successful TKA. This is achieved by correct implantation of prosthesis and soft tissue handling. However, the surgical approach and how to displace the patella are still controversial. We have carried out a cadaver study looking at the effect of patella eversion or subluxation on limb axis alignment during balancing of the knee in three different standard surgical approaches; subvastus, midvastus, or medial parapatellar. For each approach, five knees were studied. Leg alignment was visualised by the Ci CT-free DePuy/BrainLAB navigation system. Using a navigation system alignment was determined in the AP axis in both extension and 90 flexion, with the patella everted as well as subluxated. Eversion of the patella gave a more valgus axis reading than subluxation in both extension 0.58 (SD: 0.03, range 0.54 -0.60 ) and 90 flexion 0.48 (SD: 0.11, range 0.38 -0.60 ). The effect was greatest using the medial paraptellar approach. Surgeons should be aware that everting the patella influences the AP alignment when soft tissue balancing in total knee replacement.

Arthroplasty, Replacement, Knee↗
PubMed1976

Failed polycentric total knee prostheses.

Four failed polycentric total knee prostheses were evaluated by clinical examination of the patients and surface analysis of the removed prosthetic components. The failures were secondary to a poor relationship of the prosthetic components in three cases and to abutment of the tibial spine against the femoral condyle in the fourth. A poor relationship of the prosthetic components was not necessarily secondary to malpositioning, because the positioning may have been accurate but the relationships became abnormal when the knee was unstable. Scanning electron-microscope examination revealed various wear patterns but no significant correlation was noted between the morphological type and the degree of wear. Accurate placement of the components and restoration of knee stability were critical requirements for the polycentric total knee prosthesis to be successful.

Adult↗
PubMed2003

Knee scores change with length of follow-up after total knee arthroplasty.

Patients undergoing primary total knee arthroplasty (TKA) between 1989 and 1994 were evaluated preoperatively and postoperatively with the Knee Society scoring system at 3 time intervals: 1 to 2 years, 3 to 6 years, and more than 7 years. Knee prosthesis and functional scores improved statistically after TKA. At last follow-up evaluation, a statistically significant decline was found in functional knee scores that was related to an increase in numbers of patients in category C. Progression of arthritis at other sites, especially lumbar spine and hips, and cardiopulmonary problems were the most common cause of limited functional capacity. Women were found to have lower preoperative and postoperative functional scores. Patient weight, body mass index (BMI), and age at surgery showed no correlation with postoperative functional scores. The inclusion of functional categories would appear to be warranted when reporting long-term results of TKA.

Aged↗
PubMed2002

[A comparison of total knee replacement in patients with rheumatoid arthritis and those with degenerative arthritis].

This article aims at determining the differences in resources needed for the treatment of patients with rheumatoid arthritis as opposed to osteoarthritis. Data on ten patients for each of these diagnoses, all of whom had been subject to the implantation of a knee arthroplasty,were compared. We looked at parameters such as the duration of surgery, further diagnoses, costs of radiological measures and medical treatment, simultaneous operations, need of nursing care,physical and occupational therapy and complications. Patients presenting with rheumatoid arthritis in many respects required substantially more clinical and/or financial resources than osteoarthritis patients. This statement holds true at least for the period of hospital care during which the knee-prosthesis was implanted.

Arthritis, Rheumatoid↗
PubMed2001

Total condylar knee arthroplasty: a long-term followup.

Between July 1977 and December 1983, 80 patients underwent 120 arthroplasties using a total condylar knee prostheses. Forty-one patients (68 knees) died and 13 patients were lost to followup. Twenty-six patients with 34 total condylar replacements were available for clinical followup. During the followup, 10 knees in nine patients (8.3%) from the overall 80 patients (120 knees) underwent revision; three (four knees) for aseptic loosening, one for periprosthetic fracture, three for infection, and two patients underwent revision for pain. Three revisions (three patients) occurred in the group of 26 patients available for followup. The average age of this group of patients at followup was 78 years (range, 53-94 years). There were 10 men and 16 women. Considering the high mean age of the patients in the series and patients' overall health status, the clinical results were extremely good. Kaplan-Meier analysis showed a survivorship of 91% at 23 years followup, considering revision as an end point. Although there have been several changes in total knee replacement designs, materials, and implantation techniques, the long-term outcome of the original total condylar knee prosthesis is excellent.

Adult↗
PubMed2004

Biomechanical and clinical evaluation of a newly designed polycentric knee of transfemoral prosthesis.

We have designed a new polycentric knee adopting a hydraulic unit and an intelligent mechanism. The biomechanical parameters of this prototype, such as the stance duration, peak knee flexion angle in stance and swing, peak hip flexion angle, and peak hip extension moments were analyzed at three different cadences (88, 96, 104 steps/min) in three amputees, and then compared to those of polycentric hydraulic knees currently in use. The same parameters were also measured for 10 healthy volunteers and subsequently analyzed. In the prototype, almost all the values of the parameters showed no significant variety in individuals at the different cadences. The situation was the same with the healthy volunteers. However, the values of the parameter for the conventional knee varied significantly with the individual at the different cadences. The prototype may be of practical use, contributing to a stable walk even at different cadences.

Adult↗
PubMed1998

Efficacy of teicoplanin and autoradiographic diffusion pattern of [14C]teicoplanin in experimental Staphylococcus aureus infection of joint prostheses.

Prosthesis infections are difficult to cure. Infection with methicillin-resistant staphylococci is becoming more common in patients with orthopedic implants. Using a recently developed model of methicillin-resistant Staphylococcus aureus (MRSA) infection of a knee prosthesis, we compared the efficacies of teicoplanin and vancomycin. [14C]teicoplanin diffusion in this model was also studied by autoradiography. A partial knee replacement was performed with a silicone implant fitting into the intramedullary canal of the tibia, and 10(7) CFU of MRSA was injected into the knee. Treatment with teicoplanin or vancomycin (20 or 60 mg/kg of body weight, respectively, given intramuscularly twice daily) was started 7 days after inoculation and was continued for 7 days. The teicoplanin and vancomycin MICs for MRSA were 1 microg/ml. Mean peak and trough levels in serum were 39.1 and 23.5 microg/ml, respectively, for teicoplanin and 34.4 and 18.5 microg/ml, respectively, for vancomycin. Fifteen days after the end of therapy, the animals were killed and their tibias were removed, pulverized, and quantitatively cultured. Teicoplanin and vancomycin significantly reduced (P < 0. 05) the bacterial density (2.7 +/- 1.3 and 3.3 +/- 1.6 log10 CFU/g of bone, respectively) compared to those for the controls (5.04 +/- 1.4 log10 CFU/g of bone). The bacterial covents of teicoplanin- and vancomycin-treated rabbits were comparable. The [14C]teicoplanin autoradiographic diffusion patterns in rabbits with prostheses, two of which were uninfected and two of which were infected, were studied 15 days after inoculation. Sixty minutes after the end of an infusion of 250 microCi of [14C]teicoplanin, autoradiography showed that in the infected animals, the highest levels of radioactivity were located around the prosthesis and in the periosteum, bone marrow, and trabecular bone. Radioactivity was less intense in epiphyseal disk cartilage, femoral cartilage, articular ligaments, and muscles and was weak in compact bone. A similar distribution pattern was seen in uninfected rabbits. Thus, teicoplanin may represent an effective alternative therapy for the treatment of these infections.

Animals↗
PubMed2006

[Value of radiographic examination of the knee joint for the orthopedic surgeon].

Extended radiographic examinations offer excellent options for diagnosis and strategy for treatment of the knee joint. The whole-leg radiograph is indispensable in measuring alignment for osteotomy or total knee arthroplasty (TKA). Fluoroscopically assisted varus-valgus stress radiographs provide the possibility for verifying mechanical function of the implanted knee prosthesis. Ultrasound examinations have been widely replaced by magnetic resonance imaging (MRI). MRI is the golden standard to examine intra-articular structures of the knee (meniscus, ligaments, cartilage) and surrounding soft tissue. For evaluating femoral and tibial torsion and determining axial rotation of TKA, computed tomography (CT) is best qualified. Imaging of the patellofemoral joint (patella instability) is difficult; CT scans in combination with true lateral radiographs seem to be helpful.

Arthroplasty, Replacement, Knee↗
PubMed2000

Gastrocnemius myotendinous flap for patellar or quadriceps tendon repair, or both.

The authors' experience with simultaneous reconstruction of the quadriceps femoris or patellar tendon or both and soft tissue defect using a musculotendinous unit of the gastrocnemius muscle is presented. Five patients with a partial or complete defect of the quadriceps or patellar tendon or both and additional large soft tissue defects underwent reconstruction applying this technique as a one-stage surgical procedure in different variations. In cases with a partial defect of the tendon or loss of tendon thickness, the thick aponeurosis from the deeper aspect of the gastrocnemius was dissected and transferred as a pedicled tendon flap to reconstruct the tendon defect. In cases with a complete defect of the tendon, the superficial layer of the Achilles tendon together with the deep aponeurotic layer of the gastrocnemius muscle served to reconstruct the tendon. In both procedures the gastrocnemius muscle belly provided soft tissue coverage and was covered with a split thickness skin graft. One patient had a marginal deep necrosis develop that had to be covered with the other gastrocnemius muscle in a second operation. One patient with chronic polyarthritis and infection of his knee prosthesis declined additional reconstruction surgery and had the leg amputated. The average followup was 3.5 years. All patients achieved good results in active extension of the knee with an extension deficit of only 5 degrees to 15 degrees. The range of flexion was at least 90 degrees. The surgical technique described in this report provides functional tendon reconstruction and adequate soft tissue repair simultaneously.

Adolescent↗
PubMed1978

[Surgical treatment of the congenital femural defect by means of rotation plasty (author's transl)].

Experiences made in 5 cases with Borggreve's rotation plasty have shown that in cases of congenital femural defects and exceptionally also in malignant bone tumors of the distal femur this method should be suggested to the patient as a possible therapy. By rotating and shortening of the leg, the ankle joint is converted to a new knee joint. With this method an active movement of the knee joint can be obtained, so that the fitting with a below knee prosthesis becomes possible.

Abnormalities, Multiple↗
PubMed2006

Grafting of tibial bone defects in knee replacement using Norian skeletal repair system.

INTRODUCTION: The authors have been using Norian skeletal repair system (SRS) to repair cancellous bone defects in knee replacements since 1999. Norian SRS is injectable, biocompatible calcium phosphate cement with a high mechanical strength. This product is similar to the mineral phase of bone and should undergo gradual remodeling with time. We present our experience with this bone substitute in a total of 13 knee replacement surgeries. MATERIALS AND METHODS: This included three unicompartmental knee replacements (UKR), two bilateral UKR following tibial plateau fractures, five revisions of UKR to total knee replacements (TKR), two TKR revisions and one hinged knee prosthesis for significant deformity. Full weight bearing was permitted as soon as tolerated in all patients. Patients were evaluated at the latest follow-up using both the Knee Society Score (KSS) and GIUM (Italian UKR Users Group) knee scores. RESULTS: At the latest follow-up, no poor results were seen with an improvement between pre-operative and post-operative knee scores in all cases. There was no evidence of bone loss or post-operative deformity. Complete compound resorption was seen in the first 4 cases. CONCLUSIONS: The authors state that Norian SRS is a practical alternative as bone grafting in knee replacement surgery for type 1 and 2 bone defects.

Aged↗
PubMed2002

A virtual fluoroscopy system and its use for image guidance in unicompartmental knee surgery.

The C-arm fluoroscope is an indispensable intraoperative 2D imaging device for orthopaedic surgery. However, its frequent use in an operation presents a significant radiation hazard to the theatre staff and patient. A recent technique known as virtual fluoroscopy (VF) enhances the fluoroscope's capability for image guided surgery by tracking optically the position of the C-arm, surgical instruments and the patient. Virtuality is achieved by overlay of surgical instruments onto one or more previously captured fluoroscopic images. A key benefit of VF is that it reduces considerably the radiation hazard. This paper reports on a new VF technique for tracking and calibration of the fluoroscopic C-arm. Also reported is the use of our VF system to provide a new image guided technique for the accurate placement of the femoral component of unicompartmental knee prosthesis.

Arthroplasty, Replacement, Knee↗
PubMed2002

Filling of segmental bone defects in revision knee arthroplasty using morsellized bone grafts contained within a metal mesh.

For revision knee surgery with uncontained tibial bone defects, the authors report the containment of compacted morsellized allograft using metal-wire mesh, followed by implantation of a cemented total knee prosthesis. This method is comparable to the "impaction grafting technique" described for revision hip surgery and could be an alternative to metal wedges, augmented components, custom-made implants, polymethyl-methacrylate or structural bone grafts to solve some problems of cavitary and segmental bone defects in revision total knee arthroplasty.

Adult↗
PubMed1999

[Influence of knee replacement arthroplasty on modalities of weight transfer during the lateral step].

INTRODUCTION: The aim of this work was to study the relations between equilibrium and movement in patients after total knee arthroplasty. A previous study, conducted in patients with unilateral knee osteoarthritis, had shown that the timing of the events occurring during a side-step was modified in an asymmetrical way according to the supporting leg with respect to the affected one. METHOD: A kinetic and kinematic analysis was performed in a population of 9 patients before and after total knee arthroplasty and in 11 control subjects, using an ELITE system and two AMTI force-plates. The different phases (i.e. postural, monopodal, landing and stabilization) of a side step were studied. RESULTS AND DISCUSSION: Before surgery, the postural phase was longer and the monopodal phase was shorter in knee arthritis patients when the affected leg was the supporting one than when the sound leg was supporting. Total step duration and landing-stabilization phase duration were longer in patients no matter which leg was supporting than in control subjects. After total knee arthroplasty, the postural phase remained longer when the operated leg was supporting than when the sound leg was supporting. Altered proprioception can provide an explanation for this result. However, the duration of the postural phase decreased significantly when the operated leg was supporting as compared to when the affected leg was supporting before surgery. The duration of the monopodal phase was the same when the operated leg was supporting than when the sound limb was supporting and increased significantly as compared to when the affected leg was supporting before surgery. This result can be related to the decrease of pain which was observed in all patients after surgery. The duration of the landing-stabilization phase and the total movement duration remained longer in patients after surgery no matter which leg was supporting than in control subjects. CONCLUSION: This study shows that relations between equilibrium and movement tend to become symmetrical with respect to the leg used as supporting one in patients after undergoing total knee arthroplasty but remain different from those of control subjects. This movement analysis method enables to determine and to quantify differences in patients before and after undergoing total knee arthroplasty and thus provides additional information for the functional evaluation of patients with total knee prosthesis.

Aged↗
PubMed1991

The fate of hemijoint allografts after tumor resection about the knee.

Distal femoral or proximal tibial resection was performed in 15 patients for bone tumor and replaced by defrosted allogeneic osteoarticular transplants. The patients were followed for a median of 11 years (range 2 to 18 years). The major complications were 3 fractures, one delayed union, 3 graft resorptions, and one secondary infection to salvage by total knee prosthesis. Sixteen reoperations were performed in 8 patients. The small number of bone healing problems was accounted for by the autologous bone sleeve in the graft-host junction. The knee motion improved considerably after early mobilization in hinged orthosis. The early results (1 to 7 years) were as follows: excellent--3, good--6, and fair--6. The late results (8 to 18 years) were: good--4, fair--5, and poor--1. The poor result was salvaged to fair by arthrodesis. It is concluded that osteoarticular allografting yields an alternative to salvage the limb, but still presents unsolved immunologic and preservation problems which make the prognosis unpredictable.

Bone Neoplasms↗
PubMed2006

Hip and knee joint rotations differ between patients with medial and lateral knee osteoarthritis: gait analysis of 30 patients and 15 controls.

The motions and moments in the hip and knee in female patients on the waiting list for knee prosthesis surgery with medial (n = 15) or lateral (n = 15) osteoarthritis (OA) were compared with a control group (n = 15). We hypothesized that not only the kinematics and kinetics of the knee but also of the hip would differ between patients the medial and lateral groups. At midstance, patients with lateral OA showed slightly (2 degrees) more maximal (peak) adduction (p = 0.015) of the hip joint and patients with medial OA had 7 degrees more abduction (p < 0.001) than did controls. In patients with lateral OA, the femur was positioned in about 7 degrees more maximum external rotation (p = 0.001), but femur position did not differ between medial OA and controls (p > or = 0.8). There was a tendency to higher internal hip rotation moment in lateral OA compared to controls (p = 0.021). The maximum values of the internal knee abduction moments were 52% higher in medial OA (p = 0.005) and 63% lower in lateral OA (p < 0.001) compared to controls. Cases with medial OA had 9 degrees more, whereas those with lateral OA had 6 degrees less external tibial rotation than controls (medial vs. lateral OA, p = 0.001). We found an association between presence of lateral OA of the knee and the biomechanics of the hip joint. It remains to be evaluated if the changed biomechanics of the hip joint is a reason for development of lateral OA or an observation that is a result of this disease.

Aged↗