Biomechanical evaluation of porous biodegradable scaffolds for revision knee arthroplasty

Tibial bone defect is a critical problem for revision knee arthroplasty. Instead of using metallic spacer or cement, biodegradable scaffolds could be an alternative solution. A numerical model of a revision knee arthroplasty was thus developed to estimate the mechanical resistance of the scaffold in this demanding situation. The tibia, scaffold, and prosthesis were represented by simplified parameterised geometries. The maximal gait cycle force was applied asymmetrically to simulate a critical loading. Several parameters were analysed: 1) inter-individual variability, 2) cortical bone stiffness, 3) cortical bone thickness, 4) prosthesis fixation quality, and 5) scaffold thickness. The calculated scaffold strain was compared to its experimental ultimate strain. Among the tested parameters, failure was only predicted with scaffold thickness below 5 mm. This study suggests that biodegradable bone scaffolds could be used to fill bone defects in revision knee arthroplasty, but scaffold size seems to be the limiting factor.     

Retransfusion of unwashed drainage blood after total hip and knee arthroplasty]

The method of retransfusion of drainage blood as known from the literature was investigated in a prospectiv study regarding effectivness and rate of side effects. 200 patients who underwent total hip and knee arthroplasty were investigated concerning hemoglobin, hematocrit, amount and quality of the retransfused drainage blood, the amount of autologous and homologous transfusions as well as complications and costs. 100 of these patients were selected as the control group. The amount of the retransfused drainage blood after hip arthroplasty amounted an average of 387 +/- 194 ml and after knee arthroplasty 595 +/- 250 ml. The retransfused blood had an average hemoglobin of 5,2 +/- 0,9mmol/l with a hematocrit of 0,24 0,05. No complications directly associated to the retransfusion were found. The need of transfusion was reduced for patients with knee arthroplasty about 30% and for hip arthroplasty about 25%. The retransfusion of unwashed drainage blood is a sufficient method to reduce perioperative homologous blood transfusion in patients with arthroplasty of hip and knee. Substantial complications were not observed, so that this method seems to be save enough for clinical usage. The method is easy to handle and usable without special technical devices. The autologous retransfusion of drainage blood can contribute to lower costs in patients treatement.     

Osteodensitometry in uncemented total hip arthroplasty using computertomography.

The aim of this investigation was to evaluate a new method developed for the measurement of bone mineral density and bone remodelling phenomena after total hip arthroplasty using computer tomography. Computertomography is a radiological technique to examine bone structures in high resolution. Using an extended scale it is possible to investigate bone scans and implants with fewer metal artifacts. For osteodensitometry measurement a special software (IMPact HIP) for the analysis of the data was used. The measured parameters were the overall bone mineral density (mg Calcium-Hydroxyapatite/ml) and the cortical bone structure. A standard scan mode enable to compare the computertomography scans at follow-up. Nineteen total hip arthroplasty patients (20 hips) with a mean age of 58 years (31-70) were operated on using an uncemented titanium alloy stem with a tapered design. The periprosthetic bone was assessed using computertomography-assisted osteodensitometry two weeks and one year after surgery. We observed a decrease of the overall bone mineral density (15%) and of the cortical bone structure (20%) one year after insertion of the stem in the proximal part of the femur. The area corresponds to the Gruen zones 1 and 7. On the other hand, a decrease of mineral density of 5% for the overall bone and of 3% for the cortical bone was found at the level of the tip of the stem, which corresponds to the Gruen zones 3, 4 and 5. Computertomography-assisted osteodensitometry allows to investigate the bone remodelling after total hip arthroplasty by separating the analysis of the overall bone mineral density and of the cortical structure. The present method is a reliable tool for quality-control in total hip arthroplasty.     

Bone bank service in Odense, Denmark. Audit of the first ten years with bone banking at the Department of Orthopaedics, Odense University Hospital

There has been an increase in the demand for allograft bone in recentyears. The Odense University Hospital bone bank has been in function since1990,and this paper outlines our results during the 10 year period 1990–1999.Potential donors were screened by contemporary banking techniques which includea social history, donor serum tests for HIV, hepatitis B and C, and graftmicrobiology. The bones were stored at –80 °C. No typeofsecondary sterilisation was made. 423 femoral heads were approved and donatedto300 patients,1–6 heads/operation. The allografts have been used mainly toreconstruct defects at revision hip arthroplasty (34%), and for fracturesurgery(24%). 7 % of all transplanted patients were reoperated because of infection.Inthe hip revision group the infection rate was 4 %. There were no cases ofdisease transmission. During the 10 year period there was a change in theclinical use of the allografts. In the first years the allografts were mainlyused for spinal fusion surgery, but today the majority are used in hip revisionand fracture surgery. The clinical results correspond to those reported inlarger international series.     

Reconstruction with Modular Hemipelvic Endoprosthesis after Pelvic Tumor Resection: A Report of 50 Consecutive Cases

PurposeTo evaluate the effectiveness of reconstruction with a modular hemipelvic endoprosthesis after pelvic tumor resection.MethodsWe retrospectively studied 50 consecutive patients diagnosed with pelvic tumor from 2003 to 2013. All patients received limb-salvage surgery and reconstruction with modular hemipelvic endoprosthesis.ResultsPatients were followed for an average of 54 months. At the most recent follow-up, 32 patients were alive with an estimated three-year and five-year survival rate of 66.3% and 57.5% according to the Kaplan-Meier survival analysis. Eighteen patients died from the tumor, with a mean survival of 28 months, and 9 patients experienced local recurrence at an average of 19.6 months after surgery. Patients with marginal or intracapsular surgical margins had a significantly higher recurrence rate than those with wide margins (p=0.02). Metastasis occurred in 12 cases at an average of 16 months after surgery. The perioperative complication rate was 48.0%, and the most common complications were wound healing disturbance (28.0%) and deep infection (14.0%). The endoprosthetic complication rate was 16.0%, and breakage of the pubic connection plate was the most common complication. The mean Musculoskeletal Tumor Society score was 61.4%.ConclusionReconstruction with a modular hemipelvic endoprosthesis after pelvic tumor resection can improve function, with an acceptable complication rate.     

Cancellous and cortical morselized allograft in revision total hip replacement: A biomechanical study of implant stability

To restore femoral intramedullary bone stock loss in revision surgery of failed total hip arthroplasties, impacted morselized cancellous allograft is recommended. This study investigated the mechanical properties of both impacted cortical (group A) and cancellous (group B) morselized bone graft for reconstruction of femoral bones. Ten matched pairs of fresh frozen human femora were prepared by over-reaming to create a smooth-walled cortical shell. Each pair had one cortical and one cancellous impacted morselized allograft and cement. Stem subsidence was evaluated by a cyclic axial load, which was applied by a servohydraulic test. The stem subsidence was measured for initial subsidence (subsidence at the first 1000 cycles), the total axial subsidence (subsidence at the end of cycles under load) and the final axial subsidence (subsidence after the unloading phase). Torque test was measured by torsional loads through the prosthetic femoral heads. Total axial subsidence was significantly higher in group B (mean: 1.32+/-0.32 mm) compared to group A (mean: 0.94+/-0.26 mm) (P<0.01).There was no significant difference between the two groups in terms of initial subsidence (P=0.09) and final axial subsidence.The mean maximum torque before failure was 39.5+/-22.2 N-m for the cortical morselized allograft and 32.5+/-18.1N-m for cancellous.We concluded that impacted morselized cortical bone graft used for reconstruction of contained femoral bone loss in revision hip arthroplasty, may reduce the stem subsidence. Further animal experimentation for mechanical and histological evaluation of in vivo application is warranted.     

Systemic polychemotherapy in combined treatment of colon cancer]

Seven hundreds and fifty three patients with colon cancer were operated in the Unit of Colon Surgery of the State Scientific Centre of Coloproctology within the period from 1998 to 2003. 352 (46.7%) of them were subjected to systemic chemotherapy. The patients subjected to the surgical and antitumor drug therapy were divided into 3 groups according to the main disease stage: 103 (29.3%) patients with the disease stage T4N0M0 (including those with the tumor local spread), 116 (32.9%) patients with the disease stage T(3-4)N+M0 and 133 (37.8%) patients with the disease stage T(3-4)NxM1. In the patients with the colon serous membrane diffusion and locally spread tumors (total of 103 patients) 3- and 5-year survival was stated in 81.0 +/- 2.8% and 76.5 +/- 3.7% respectively. The control group included 85 patients subjected to the surgical treatment alone. In the latter group 5-year survival was recorded in 68.0 +/- 2.9% of the patients. In the group of the patients with affection of the regional lymph nodes subjected to antitumor drug therapy 3- and 5-year survival was recorded in 64.1 +/- 3.5% and 57.5 +/- 4.2% respectively. In 52 patients not subjected to the systemic chemotherapy the analogous index was equal to 44.5 +/- 3.4%. The systemic chemotherapy was applied to 111 (78.2%) patients with metastases to the liver. In 50 of them cytoreductive operations were performed and in 61 patients palliative resection of the colon was carried out. The average period without clinical manifestations of the disease in the patients subjected to the colon palliative resection and systemic chemotherapy was equal to 8.5 +/- 3.5 months. In the patients with metastases to the liver subjected to the cytoreductive operations the average lifespan after the operations amounted to 24.5 months. The average lifespan of the patients with canceromatosis subjected to the systemic chemotherapy and cytoreductive operations amounted to 13.5 months. When the chemotherapy in such patients was effective the average lifespan was 16 months, while in case of the therapy failure it was 8.5 months.     

骨保留型短柄假体行全髋关节置换手术早期疗效观察

目的:探讨骨保留型股骨短柄假体行全髋关节置换手术的近期疗效及临床体会。方法:自2013年1月~2015年3月,首次接受人工全髋关节置换术共30例患者(38髋),年龄38~70岁,均采用后外侧入路。通过比较术前、术后髋关节Harris评分、骨性关节炎指数可视化量表(WOMAC),评价手术疗效。结果:术后所有患者均获得随访,最少6月,最长33月,平均19.5月。术后髋关节疼痛均明显好转,随访期内无严重并发症发生。髋关节Harris评分:术前45.3±4.3,术后末次随访94.1±5.4。术后末次随访Harris评分较术前改善明显,差异有统计学意义(P0.05),术后3~4个月所有患者可以全负重行走。1例术中股骨近端骨折,术后愈合良好,未留后遗症。所有病例未发现假体松动或感染。结论:骨保留型股骨短柄假体行全髋关节置换手术近期临床效果满意,无严重并发症。新型短柄假体设计符合人体解剖特征,骨量保留多,术后疗效好,为髋关节置换提供了一种新的选择。     

Early repair and breast-feeding for infants with cleft lip

This study attempts to define the effect of early repair and breast-feeding on the outcome of cleft lip surgery. The first part deals with 100 consecutive cleft lip repairs categorized retrospectively by age at operation. Forty-nine patients were operated on during the first 3 weeks of life; 51 at an older age. There were no statistically significant differences in complication rate between the groups (14 and 18 percent, respectively). A subgroup of 26 infants was operated on at a week or less of age; these sustained significantly fewer complications (8 percent). There was no apparent difference in the operative results as defined by whether or not the child needed a subsequent revision. A second group of 60 mothers was offered the choice of breast-feeding their babies immediately following operation. Sixteen breast-fed for a minimum of 6 weeks, 22 were fed by means of a cup or syringe, and 22 started breast-feeding but converted to a bottle within 6 weeks. No complications attributable to breastfeeding were observed, and the rate of weight gain was definitely enhanced in the breast-feeding group. Hospital stay was shortened by an average of over a day (33 percent) as compared with those fed by cup. This effect was related to the easier transition from IV administration to oral intake when breast-fed. We are currently encouraging early repair and breast-feeding in the full-term baby as the optimum method of management of newborns with cleft lip.     

Vertical versus Wise pattern breast reduction: patient satisfaction, revision rates, and complications

A prospective, randomized study was designed to compare the outcome of inferior pedicle/Wise pattern reduction (group I) with medial pedicle/vertical pattern reduction (group II) in moderate resections averaging 500 g per breast. There were 105 women in group I and 103 women in group II. All surgical procedures were performed by the same plastic surgeon. Patient information recorded included age, body mass index, type of surgery, weight of specimen, need for surgical revision, and complications. Six months postoperatively the patients were asked to complete a questionnaire, which rated their satisfaction with the surgical outcome. The questionnaire used a 10-point response format ranging from very disappointed (score of 1) to very pleased (score of 10). The results demonstrated that there was no significant difference between the groups in age (31 +/- 12 versus 29 +/- 13 years), body mass index (26 +/- 4 versus 27 +/- 5), and amount of tissue excised (553 +/- 203 g versus 548 +/- 205 g). Group I required no surgical revisions, but in group II revisions for dog-ears were required in 11 percent. The rate of other complications was similar in both groups. Patients' evaluations of breast size, shape, symmetry, nipple sensation, symptom relief, ease of brassiere/clothing fitting, and overall satisfaction were not significantly different. The vertical mammaplasty was ranked significantly (p < 0.05) higher by patients in regard to scars (6 +/- 2 versus 3 +/- 3) and overall aesthetic results (8 +/- 1 versus 6 +/- 3). In the management of moderate macromastia, this study indicates that patients who have a vertical reduction are less disappointed with the scars but require a significantly higher rate of surgical revisions compared with patients who have a Wise pattern reduction.     

Influence of demographic, surgical and implant variables on wear rate and osteolysis in ABG I hip arthroplasty

Periprosthetic osteolysis is associated with accelerated wear rates. The goal of this study was to investigate the influence of demographic and technical variables on wear rates and size of osteolytic lesions. Eighty retrieved ABG I prostheses were analyzed according to prospectively established criteria. There were 22 men and 58 women with an average age of 52 years (34-65) at the time of revision. The average time from index surgery to revision was 67 months (26 to 106). Polyethylene wear measurements were performed using a Universal-type measuring microscope. The average linear wear and volumetric wear rate was 0.363 mm per year (0-0.939, SD 0.241) and 161 mm(3) per year (0-467, SD 118.2), respectively. The wear rates were significantly higher (a) in patients with primary osteoarthritis in comparison with postdysplastic hips, (b) in hips where zirconia prosthetic heads articulated against the polyethylene liner, and (c) in cups placed laterally to Kohler's line. Risk that linear wear rate could be more than 0.2 mm per year was three times higher in patients who were operated in 1997 and later (OR 3.0, 95 % CI 1.126-7.993, p = 0.03). A strong association was revealed between magnitude of wear and size of femoral osteolysis.     

Useability of an image based nagivation system in reconstruction of leg alignment in total knee arthroplasty - results of a propsective study]

Accurate leg alignment is one important factor for long term survival in total knee arthroplasty (TKA). The aim of this study was to determine the accuracy of a CT-based navigation system in restoration of the leg axis. 80 TKA (P.F.C.-Sigma--DePuy) were implanted either using a CT-based navigation-system or the conventional technique. There were no significant differences between the groups according to the preoperative leg deformity. Accuracy of implantation was determined on postoperative long-leg coronal and lateral x-rays. A postoperative leg axis between 3 degrees varus and 3 degrees valgus was obtained in 35/40 patients (88%) in the computer assisted and 28/40 patients (70%) in the conventional operated group. A higher precision in the sagittal plane was seen for the tibial (computer assisted: 3.9 +/- 2.2 vs. conventional TKA 1.3 +/- 5.8) and the femoral component (computer assisted: 3.5 +/- 2.3 vs. conventional TKA 6.9 +/- 3.6). The use of the CT-based VectorVision-System allows a significant improvement in the accuracy of implantation in TKA. The CT-based module has the advantage of a precise preoperative planning and a useful documentation and control tool for each important step. On the other hand there are additional costs and time consuming logistics.     

Lead content in the femoral heads of inhabitants of Silesia (Poland).

Lead content was evaluated in spongious and cortical bone as well as in cartilage surface of human femoral heads obtained during hip arthroplasty from 45 inhabitants (11 males and 34 females) of the industrial region of Upper Silesia. The average age of this group was 63.9+/-14.4 years. Lead content was assessed using microwave mineralization with the graphite furnace atomic absorption spectrometry (GFAAS) method. The average lead content in the specimens from spongious bone was 2.56 microg/g, 3.05 microg/g in cortical bone and 3.53 microg/g in cartilage surface. The calculated average Pb/Ca ratio was 1783x10(-8) in spongious bone, 1623x10(-8) in cortical bone, and 2512x10(-8) in the cartilage. Both lead concentration and Pb/Ca ratio increased with the age of the patients. Higher lead content was found in the specimens from male hips and in the group of cigarette smokers.     

Elevated serum leptin levels in patients with acute myocardial infarction; correlation with coronary angiographic and echocardiographic findings

ABSTRACT: BACKGROUND: To assess the relationship between serial serum leptin levels in patients with acute myocardial infarction (AMI) who received thrombolysis and the degree of coronary atherosclerosis, coronary reperfusion, echocardiographic findings, and clinical outcome. 51 consecutive patients presenting with AMI were studied. Clinical characteristics including age, sex, body mass index (BMI) and cardiovascular risk factors were recorded. Serial serum leptin levels at the time of admission and subsequently at 0, 6, 12, 24, 36, 60 hours afterwards were obtained. Coronary angiography was performed in 34 patients; the relation between serum leptin levels and evidence of coronary reperfusion as well as the extent of coronary atherosclerosis according to the coronary artery surgery study classification (CASS) were evaluated. Echocardiographic evaluation was performed in all patients. 36 matched patients were enrolled as control group who had serum leptin level 9.4 +/- 6.5 ng/ml. RESULTS: The patients mean age was 50.5 +/- 10.6 years. There were 47 males and 3 females. 37.1% were diabetics, 23.5% were hypertensive, 21.6% were dyslipidemic and 22.7% were obese (BMI [greater than or equal to] 30). Leptin concentrations (ng/ml) increased and peaked at the 4th sample (36 hrs) after admission (mean +/- SD) sample (1) =9.55 +/- 7.4, sample (2) =12.9 +/- 8.4, sample (3) =13.8 +/- 10.4, sample (4) =18.9 +/- 18.1, sample (5) =11.4 +/- 6.5, sample (6) =10.8 +/- 8.9 ng/ml. There was a significant correlation between serum leptin and BMI (r = 0.342; p =0.03). Leptin levels correlated significantly to creatine kinase level on the second day (r = 0.43, p [less than or equal to] 0.01). Significant correlation of mean serum leptin with the ejection fraction (P < 0.05) was found. No difference in timing of peak serum leptin between patients who achieved coronary reperfusion vs. those who did not (p= 0.8). There was a trend for an increase in the mean serum leptin levels with increasing number of diseased vessels. There was no correlation between serum leptin levels and outcome neither during the hospitalization nor at 9 months follow up. CONCLUSION: Serum leptin levels increase after myocardial infarction. Serum leptin level may be a predictor of the left ventricular ejection fraction and the degree of atherosclerosis but not of coronary reperfusion.     

Palmar shelf arthroplasty, the next generation: distraction/interposition for rheumatoid arthritis of the wrist

Rheumatoid arthritis affects approximately 1 percent of the adult population. Bilateral symmetric involvement of the wrist occurs in 85 percent of these patients, with recurrent flares and relentless progression. Anatomic changes consist of radiocarpal, intercarpal, and radioulnar subluxation and joint destruction. For advanced disease, both wrist arthrodesis and arthroplasty have been recommended. Arthrodesis has been successful for pain relief at the expense of motion. Implant arthroplasty has been unreliable, with failure rates of 25 to 50 percent at 2 to 9 years. Palmar shelf arthroplasty was introduced in 1970 as a resectional fibrous arthroplasty. The results were good but the series was small. Subsequent reports of this procedure have been inconsistent. In 1990, I initiated and have since followed a series of patients treated with the palmar shelf arthroplasty. To the basic procedure, I added joint distraction by external fixator, collagen/bone wax interposition, scapholunate stabilization, and increased immobilization time. Fourteen consecutive patients were enrolled in this study. Each carried a diagnosis of rheumatoid or psoriatic arthritis of the wrist. There were 11 women and 3 men. Age ranged from 28 to 56 years. Follow-up ranged from 2 to 7 years (average 4.2). The patients were interviewed, examined, and x-rayed. A questionnaire using an analog scale as well as the Hospital for Special Surgery scoring system was completed to assess the clinical outcome of the wrist postoperatively compared with its preoperative status and with the contralateral wrist. No patient has requested or required a revision procedure. All patients experienced improvement with both pain and function; no wrist spontaneously fused. Patient satisfaction was high. Patients with ipsilateral arthroplasty and contralateral arthrodesis preferred the arthroplasty. Hospital for Special Surgery score increased from 53 to 91 out of 100 points (p < 0.001). Range of motion averaged 50 degrees flexion, 30 degrees extension. Palmar shelf arthroplasty remains a viable option for severe rheumatoid disease of the wrist. Ideally, the procedure is performed on the dominant wrist of a patient with bilateral wrist involvement in the setting of inflammatory arthritis.     

Assessment of bone healing during callus distraction by an automatic torsional stiffness metering system]

The present article describes a newly developed device for the quantitative assessment of torsional in vivo stiffness of regenerating bone under callus distraction. Both the design and function of this device, and its use during bony consolidation are discussed. The device exhibited an accuracy of +/- 18% for stiffness under 0.1 Nm/degree, and +/- 5% stiffness above 0.1 Nm/degree. The average accuracy was +/- 14%. The data scatter for the stiffness measurement ranged between +/- 1.43% and +/- 7.68% (average: +/- 3.99%). The precision of a test machine was between +/- 0.01% and +/- 11.3% (average: +/- 3.65%). The method has the following advantages over existing methods for investigating healing: 1. no need to dismantle the external fixation for measurement; 2. preservation of the bone axis with minimal risk of misalignment during the bone healing process; 3. minimal technical requirements, with easy, noninvasive measurement; 4. no exposure to X-radiation.     

Suppressive effects of genistein dosage and resistance exercise on bone loss in ovariectomized rats.

This study was designed to determine whether combined treatments with genistein dosage and moderate resistance exercise would exhibit synergistically preventive effects on bone loss following the onset of menopause. Forty-one 12 wk-old female SD rats were assigned to five groups: 1) Sham operated (Sham); 2) ovariectomized (OVX-Cont); 3) OVX received genistein (OVX-GEN); 4) OVX exercised (OVX-EXE); and 5) OVX treated with both genistein and exercise (OVX-GEN-EXE). All rats were fed a low Ca (0.1%) diet ad libitum. Daily genistein dosage was 12 mg/kg body weight. Exercising rats took 40 sets of 1-min run interspersed with 1-min rest with a 100 g weight on the back on an uphill treadmill at 20 m/min. The experimental duration consisted of the adaptation and treatment periods of 4 weeks each. Uterine weight in OVX-Cont, OVX-GEN, OVX-EXE and OVX-GEN-EXE decreased to about 15% of that in Sham (p < 0.001). The femoral BMD (mg/cm2; mean +/- SE), assessed by DEXA (Lunar), of OVX-Cont was significantly lowered to 206 +/- 5 by -9%, as compared to 226 +/- 2 of Sham (p < 0.001). The BMD of OVX-GEN, OVX-EXE and OVX-GEN-EXE were 217 +/- 2, 217 +/- 2 and 222 +/- 2, respectively, and genistein dosage and resistance exercise equally increased the BMD of OVX rats by 5% (p < 0.01). Combined treatment of genistein and exercise more successfully recovered their decreased BMD by 8% (p < 0.001). BMD of the fourth lumbar vertebrae in OVX-Cont was declined to 191 +/- 7 by -15%, as compared to 225 +/- 4 in Sham (p < 0.001). OVX-EXE and OVX-GEN-EXE gained the BMD by 6% to 205 +/- 4 and 203 +/- 3, respectively, as compared to that of OVX-Cont (p < 0.01). These results suggest the possibility that the combined treatment of genistein dosage and resistance exercise have more beneficial effects by acting rather independently than their separate trials on the prevention of ovx-induced bone loss in femurs.     

Ciprofloxacin in the prevention and treatment of surgical infections]

A clinico-laboratory study on ciprofloxacin made by Bayer (Germany) was applied to patients with extended posttraumatic wounds and performed with the aim of preventing postoperative purulent complications in patients operated on the organs of the gastrointestinal tract. In the both groups ciprofloxacin was administered orally in doses of 500 and 1000 mg and intravenously in a dose of 200 mg. The results of the assay on ciprofloxacin sensitivity of the isolates from the wound excretion and urine showed that they were more sensitive to ciprofloxacin than to aminoglycosides and cephalosporins. 15 minutes after the intravenous administration the serum concentration of ciprofloxacin amounted to 7.5 +/- 0.9 micrograms/ml and in 6 hours it was equal to 0.45 +/- 0.45 micrograms/ml, the mean concentrations of ciprofloxacin being attained in the bile (8.7 +/- +/- 3.9 micrograms/ml), gallbladder wall (5.5 +/- 3.8 micrograms/g), liver (0.73 micrograms/g), muscles (1.93 micrograms/g) and tendon (0.15 microgram/g). After the oral administration in a dose of 500 mg ciprofloxacin was detected in the blood serum in an amount of 2.0 +/- 0.7 micrograms/ml in 1 hour and in an amount of 0.9 +/- 0.13 micrograms/ml in 6 hours. After the drug oral administration in a dose of 1000 mg the maximum concentrations were: 6.34 +/- 4.2 micrograms/ml on the average and 2.1 +/- 0.8 micrograms/ml in 6 hours (0.4 micrograms/g in the muscles, 1.4 micrograms/g in the skin and 0.34 micrograms/g in the bones). The study showed that ciprofloxacin was a highly efficient antimicrobial agent in the treatment of the complicated wound infections and the prophylaxis of the purulent complications during the postoperative period in the patients operated on gastrointestinal organs.     

Validation data for periprosthetic bone remodelling theories

Periprosthetic adaptive bone remodelling after total hip arthroplasty (THA) has been frequently simulated in computer models, combining bone remodelling theory with finite element analysis. Unfortunately, there still subsist a lack of clinical data, which are necessary for validation of these simulation results. Therefore, the objective of the current project is to collect prospective volumetric bone density data with a clinical computerized tomography study in seven patients after THA. A retrospective study 12 years after implantation in 11 patients was added. A data set of about 100 000 bone voxels for each femur was collected. In all prospective cases, the predominant change is seen during the first year. The average density reduction in the horizontal slices was between 50 and 150 Hounsfield units (HU) (approx. 10%; p<0.001) after 2 years. Loss of density is particularly strong distal of the minor trochanter and decreases from proximal to distal.

For the 12 years retrospective study, the contralateral femur provided the control. Similar trends comparable to the prospective 2-year follow-up CT density values were seen in most cases with density reductions of up to 400 HU (30%). However, in one of these cases there was no difference between the operated and the control density.

As far as we are aware, this is the first collection of fully prospective 3D validation data in vivo for periprosthetic adaptive bone remodelling theories. The data are also unique as they are suitable for direct patient-specific 3D finite element meshing and individual weight-related loading.     

Complications after primary and secondary transsclerally sutured posterior chamber intraocular lens implantation

This retrospective study analyses and compares early complications during the first month after primary and secondary posterior chamber implantation of transsclerally sutured IOL. The analysis covered medical records of 65 patients who underwent posterior chamber implantation of transsclerally sutured IOL at the Eye Clinic in Rijeka between 1998 and 2003. In 30 patients (group 1) lenses were implanted in one eye during complicated cataract surgery (primary implantation), whereas 35 patients (group 2) had lenses implanted afterwards (secondary implantation). There were 77 early complications, equally represented in both groups, i.e. 40 in (51.9%) the first and 37 (48.1%) in the second group. The most frequent complications were: vitreous hemorrhages 24.7% (14.3% and 10.4%), cystoid macular edema 19.5% (9.1% and 10.4%), keratopathy 14.3% (6.5% and 7.8%), pupil distortion 11.7% (9.1% and 2.6%), IOL decentration and tilt 10.4% (6.5% and 3.9%), high intraocular pressure 9.1% (2.6% and 6.5%), inflammation 6.5% (2.5% and 3.9%). Retinal and choroidal detachment had low incidence: 2.6% (1.3% and 1.3%) and 1.3% (0% and 1.3%) respectively. As concerns early complications, there were no statistically significant differences between the two groups, except for pupil distortion, which was more frequent in primary IOL implantation (p = 0.045). After primary implantation of IOL, the average visual acuity was 0.38 +/- 0.27, whereas after secondary implantation visual acuity was 0.52 +/- 0.21. The difference was not statistically significant.