The influence of compressive forces across the patellofemoral joint on patient-reported outcome after bi-cruciate stabilized total knee arthroplasty.

AIMS: Patellofemoral problems are a common complication of total knee arthroplasty. A high compressive force across the patellofemoral joint may affect patient-reported outcome. However, the relationship between patient-reported outcome and the intraoperative patellofemoral contact force has not been investigated. The purpose of this study was to determine whether or not a high intraoperative patellofemoral compressive force affects patient-reported outcome. PATIENTS AND METHODS: This prospective study included 42 patients (42 knees) with varus-type osteoarthritis who underwent a bi-cruciate stabilized total knee arthroplasty and in whom the planned alignment was confirmed on 3D CT. Of the 42 patients, 36 were women and six were men. Their mean age was 72.3 years (61 to 87) and their mean body mass index (BMI) was 24.4 kg/m 2 (18.2 to 34.3). After implantation of the femoral and tibial components, the compressive force across the patellofemoral joint was measured at 10°, 30°, 60°, 90°, 120°, and 140° of flexion using a load cell (Kyowa Electronic Instruments Co., Ltd., Tokyo, Japan) manufactured in the same shape as the patellar implant. Multiple regression analyses were conducted to investigate the relationship between intraoperative patellofemoral compressive force and patient-reported outcome two years after implantation. RESULTS: No patient had anterior knee pain after total knee arthroplasty. The compressive force across the patellofemoral joint at 140°of flexion was negatively correlated with patient satisfaction (R 2 = 0.458; ß = -0.706; p = 0. 041) and Forgotten Joint Score-12 (FJS-12; R 2 = .378; ß = -0.636; p = 0. 036). The compressive force across the patellofemoral joint at 60° of flexion was negatively correlated with the patella score (R 2 = 0.417; ß = -0.688; p = 0. 046). CONCLUSION: Patient satisfaction, FJS-12, and patella score were affected by the patellofemoral compressive force at 60° and 140° of flexion. Reduction of the patellofemoral compressive forces at 60° and 140° of flexion angle during total knee arthroplasty may improve patient-reported outcome, but has no effect on anterior knee pain.

[Toxicological studies on sophorolipid derivatives. (I). Acute toxicity, eye irritation, primary skin irritation, skin sensitization, phototoxicity, photosensitization, mutagenicity of polyoxypropylene (12) [(2'-0-beta-D-glucopyranosyl-beta-D-glucopyranosyl)oxy-] fatty acid ester-].

Acute toxicity, eye irritation, primary skin irritation, skin sensitization, phototoxicity, photosensitization and mutagenicity of sophorolipid derivatives were studied in rats, mice, rabbits, guinea pigs and Salmonella typhimurium strains. The acute oral toxicity of sophorolipid (SL) which Torulopsis bombicola produces, and its derivatives (PSL, Ethyl-SL and Oleyl-SL) were shown to be very low. The LD50 values of PSL ranged from 10 g/kg to 16 g/kg on oral administration in rats and mice, and from 5.8 g/kg to 6.6 g/kg on subcutaneous administration in mice. The oral LD50 values of Ethyl-SL and Oleyl-SL were estimated to be greater than 15 g/kg and that of SL was 12.5 g/kg. In eye irritation study, PSL failed to produce any reactions at 50% concentration even when the rabbit eye was not subsequently washed. SL, Ethyl-SL, Oleyl-SL and Tween 20 were "no irritant" or "slight irritant" to the rabbit eye at 20% concentration. PSL showed no irritancy to both the intact and abraded guinea pig skin at 50% concentration. And in other examinations, it was also indicated that PSL had no potentials of skin sensitization, phototoxicity and photosensitization in guinea pigs and had no potentials of mutagenicity in Salmonella typhimurium TA98 and TA100.

[Toxicological studies on sophorolipid derivatives. (II). Subacute toxicity study of polyoxypropylene (12) [2'-0-beta-D-glucopyranosyl-beta-D-glucopyranosyl) oxy-] fatty acid ester-].

Five groups of 12 male and 12 female rats each were fed diets containing 0, 0.06, 0.25, 1.00 and 4.00% PSL for a period of one month. Food consumption of PSL-fed groups did not differ from that of control. Urinalysis and autopsy findings were within normal in every group of rats treated. With 4.00% in the diet, body weight gain was significantly retarded and water consumption was increased, and soft stool occurred. In the hematological examination, decrease of red blood cells and increase of white blood cells were observed at the levels of 1.00 and 4.00% PSL. Changes of white blood cell differentials were also seen at the same levels. Serum Na+ concentration was slightly decreased at the 0.25, 1.00, 4.00% levels and serum glucose was also decreased at the 1.00, 4.00% levels, but the values were within the normal limits. Significant increase of relative liver weight, without histopathological changes, was observed at the 4.00% level. Histopathological examination revealed slight erosion, necrosis or intestinitis in small intestine, at the levels of 0.25, 1.00, 4.00% PSL. It was considered that these findings were attributed to the irritation potential of PSL or its metabolite. These results indicated that the non-effect level was 0.06% (53 mg/kg/day) and the level causing no toxicological effect was 0.25% (208 mg/kg/day), but no deleterious effects was observed in the levels greater than 0.25%.

Pedunculated hepatoma--report of two cases and review of the literature.

Although pedunculated hepatoma has received little attention in the United States and Europe, in Japan more than forty cases have been reported, probably owing to the relatively high frequency of hepatoma. Formerly preoperative diagnosis was difficult in the early period. Recently it can be made by ultrasound, computed tomography and angiography, however, the choice of operative procedure is not uniform. In some cases good results were obtained by only tumor excision or partial hepatic resection, whereas other cases presented undergoing more extended resection show a poorer course. In the present case 1, intrahepatic recurrence was recognized three months after surgery in spite of relatively early diagnosis. Reviewing the literature, it appears that the degree of invasion at the pedicle is mainly related to prognosis. If invasive, segmentectomy or lobectomy is necessary and postoperative adjuvant therapy is needed.