Midterm results of modular hinge total knee arthroplasty using cementless osseointegrating stems: low fixation associated complications and good functional outcome in primary and revision knee arthroplasty.

PURPOSE: This study aimed to investigate functional outcome and complications after primary and revision modular H-TKA using hybrid fixation with cementless stems. METHODS: Between 2015 and 2018, 48 patients with 50 implants were included after hybrid implantation of a single design H-TKA system using cementless osseointegrating stems and modular components. Complications and clinical outcome were analysed using Knee Society Score (KSS), the Western Ontario McMasters Universities Osteoarthritis Index (WOMAC) and the Short-Form Health Survey 12 (SF-12) score. RESULTS: Indications for implantation were aseptic revision (n = 29, 58%), primary TKA (n = 19, 38%) and two-stage septic revisions (n = 2, 4%). Complications were reported in 26% (n = 12), whereas complications associated with hybrid fixation occurred in 5 (10%) cases, with 2 (4%) requiring revision surgery for aseptic loosening and 3 (6%) treated with an adapted postoperative protocol for perioperative fractures. Implant survivorship was 84% after a mean follow-up of 54 months. Postoperative KSS significantly improved from 51.50 (12-100) to 78.36 (41-99; p < 0.001). The mean WOMAC score was 19.26 (0-55), SF-12 PCS was 41.56 points (22.67-57.66) and SF-12 MCS was 49.21 points (23.87-63.21). CONCLUSION: Hybrid modular implantation in H-TKA provides satisfactory clinical and functional results in primary and revision TKA. Clinical outcomes significantly improve with reduced pain, increased mobility, and good-to-excellent functional scores after implantation. Whilst implant survival is comparable to previous studies and complications associated with hybrid fixation are low, general complication rates are comparably high.

Qualifying for bariatric surgery: is preoperative weight loss a reliable predictor of postoperative weight loss?

BACKGROUND: Over the last 20 years, bariatric surgery has emerged as a highly effective weight loss intervention that can also improve co-morbid medical conditions. However, some payors have required preoperative supervised diets and weight loss. OBJECTIVE: To determine if preoperative weight loss is the best predictor of postoperative weight loss. SETTING: Academic county hospital, United States. METHODS: A retrospective chart review of 218 patients. Patients who received psychological evaluation and bariatric surgery were followed up at 1 year. All preoperative patients were encouraged to lose weight; however, no specified amount of weight loss was required. Preoperative weight loss and postoperative weight loss in body mass index (BMI), percent excess weight loss, and percent total weight loss were measured. Bariatric outcome predictor variables evaluated included age, race, and sex; BMI change; measures of depression and anxiety; number of unhealthy eating types; and co-morbid medical conditions. A linear regression model and stepwise regression analyses were used to estimate contributions of independent variables to the 1-year weight loss. RESULTS: All patients had a mean 28% reduction in BMI (63.3% excess weight loss and 29.1% total weight loss) at 1 year postoperatively. As a single independent variable, preoperative weight loss was a significant predictor of 1-year change in postoperative BMI (P = .006). However, when age, race, and sex were added to the regression equation, the predictive value of preoperative weight loss became nonsignificant (P = .543). CONCLUSION: The present findings indicate that preoperative weight loss should not be considered in isolation when clearance for bariatric surgery is being evaluated.

Is radiation treatment volume a predictor for acute or late effect on pulmonary function? A prospective study of patients treated with breast-conserving surgery and postoperative irradiation.

BACKGROUND: When tangential radiation beams are used in patients with breast cancer after breast-conserving surgery, the amount of lung included in the radiation field varies because of patient anatomy and treatment technique. The question of how much lung tissue can be irradiated incidentally without acute or late complications requires quantitative study. METHODS: Thirty-four women were enrolled in a prospective study of pulmonary function after breast-conserving surgery and radiotherapy for early stage breast cancer. The percentage of lung volume irradiated was estimated from computed tomography scans. Pulmonary function tests including spirometrics, lung volume, and diffusing capacity of carbon monoxide (DLCO) were performed before, during, and at regular intervals after radiotherapy. Both acute and long term changes in pulmonary function were analyzed in 29 eligible patients. RESULTS: Acutely, DLCO values dropped, but they returned to normal levels by 24 months. At 5 years, pulmonary function did not vary significantly according to the percentage of lung irradiated, the use of regional lymphatic irradiation, or the addition of chemotherapy. Symptomatic pneumonitis occurred only in two women with baseline deficits in DLCO (P = 0.016), who had more than 10% of the total lung volume irradiated. Patients with a smoking history had a clinically significant baseline deficit of 32% in DLCO values (P = 0.0011) but showed a 21% improvement (P = 0.11), which probably correlated with quitting smoking. CONCLUSION: Within the range evaluated in this study, the volume of lung irradiated did not predict a late decrease in pulmonary function, although pneumonitis was observed only when more than 10% of the lung was irradiated.

Radiation therapy for skin cancer near the eye: kilovoltage x-rays versus electrons.

When skin cancer near the eye is irradiated, a corneal shield is placed between the lids and globe to protect ocular structures. The effectiveness of the shield was evaluated with 250 kVp x-ray and 6-20 MeV electron beams. To simulate the clinical situation, a face phantom was constructed out of solid pieces of water-equivalent epoxy. In the region of the eye the phantom was milled to the exact contour of a human face. The phantom was used to reconstruct the setup that had been used to treat a patient with a 1-cm basal cell carcinoma of the mid portion of the lower lid. A medium-sized corneal shield (2-mm-thick lead plated with 0.1 mm gold) was placed on the eye portion of the phantom. A contoured lead (6 mm thick) face mask was placed on the surface of the phantom to define a 3-cm diameter radiation field that included only the inferior hemisphere of the shield. The doses that the cornea, lens, and retina would receive beneath the midpoint of the inferior hemisphere of the shield were measured using thermoluminescent and film dosimetry. With 6 to 8 MeV electrons, the corneal dose was 2 to 4 times higher than with 250 kVp x-rays. Corneal and lens doses rose rapidly with increasing electron beam energy such that with greater than 8 MeV the shield would provide relatively poor ocular protection. A scanning ion chamber and film dosimetry were used to determine the isodose profiles of 250 kVp x-ray and 6 MeV electron beams for a 3-cm diameter field collimated on the surface. With 250 kVp x-rays the 95% isodose area was 32% wider than with 6 MeV electrons. The ease of shielding and the ability to minimize field size argue in favor of kilovoltage x-rays for early-stage skin cancer near the eye.

Effects of the antiandrogen, cyproterone acetate, on the induction of papillomas, DNA synthesis and ornithine decarboxylase activity in mouse skin.

The antiandrogen, cyproterone acetate (CPA), applied simultaneously with 12-O-tetradecanoylphorbol-13-acetate (TPA) to the dorsal skin of male and female SENCAR mice initiated with 7,12-dimethylbenz[a]anthracene inhibited the production of papillomas of the skin. Although 125 and 250 micrograms of CPA had no effect on the incidence of papillomas per mouse, 500 micrograms of CPA inhibited papilloma production by 95% and 91% in female mice after 20 and 37 weeks of promotion, respectively. Testosterone propionate only partially blocked the inhibitory effect of CPA. In male mice 500 micrograms and 1 mg of CPA inhibited papilloma production by 77% and 88%, respectively. In the two-stage promotion protocol 500 micrograms of CPA was ineffective as an inhibitor when it was applied with TPA during the 1st stage but inhibited papilloma production by 71% when it was applied with mezerein during the 2nd stage. CPA was also observed to inhibit TPA-stimulated epidermal DNA synthesis and inflammation but had no effect on TPA-induced epidermal ornithine decarboxylase activity.

The contribution of internal scatter to radiation dose during CT scan of the head.

An acrylic head phantom was irradiated during a computed tomographic scan with four commercial scanners. Measurements of the spatial distribution of the radiation dose on the surface and internal to the phantom were performed for the scan plane and the scattered beam at various distances from the scan plane. The surface scatter dose was found to be considerably smaller than that for internal scatter. A significant increase in radiation exposure within the head phantom due to internal radiation scatter, and an asymmetrical primary beam profile for dual slice scanners were also noted.

Storage of platelets prepared by discontinuous flow centrifugation.

Platelet concentrates were prepared by plateletpheresis using discontinuous flow centrifugation. Platelet units were stored in PL-146 bags of 300 ml and 2,000 ml capacity, and in vitro measures helpful in predicting platelet viability were compared. Storage in bags of 300 ml capacity led to significant fall in pH, decreased recovery from osmotic stress, and deterioration of morphology in 24 hours. Storage lesions were significantly decreased by use of 2,000 ml capacity bags.