Aim of this prospective, randomized study is to introduce and compare a new technique of reduction of the anterior dislocation of the shoulder with the “Hippocrates” and “Kocher” methods, as far as its efficacy, safety and intensity of the pain felt by the patient during the reduction, are concerned. This is the first reported prospective, randomized comparative study of three reduction techniques of anterior dislocations of the shoulder.

154 patients suffering from acute anterior shoulder dislocation participated in the study. Patients were randomly assigned to one of the three study groups (New, “Hippocrates” and “Kocher”) and underwent reduction of their dislocation performed by residents orthopaedic surgeons.

The groups were statistically comparable (age, male/ female ratio, mechanism of dislocation, mean time interval between injury and first attempt of reduction).

Reduction was achieved with the “Fares” method in 88.6%, with the “Hippocrates” in 72.5% and with the “Kocher” in 68% of the patients. This difference was statistically significant, favoring the new method (p=0.033). The mean duration of the reduction (p=0.000) and the mean reported by the patients VAS with the new method (p=0.000) were also statistically significantly lower than those of the other methods. No complications were noted in any group.

The new method seems to be more effective, faster and less painful method of reduction of the anterior shoulder dislocation, when compared with the “Hippocrates” and the “Kocher” methods. It is easily performed by only one physician and it is not more morbid that the other two methods.

The aim of this study is the presentation of the midterm results of the radial head replacement with pyrocarbon head prosthesis (MoPyc).

Thirty two patients (20 males and 12 females) with a mean age of 54 y.o. (32–68 y.o.) were subjected to replacement of the radial head with a pyrocarbon head prosthesis. Twenty of them had a comminuted radial head fracture(15 Mason IV type and 5 Mason III), two had a malunion and ten had a complex elbow injury (ligamentous rupture and comminuted radial head fracture with/without coronoid process fracture). In 22 patients the fracture was on the dominant side. The mean follow up time was 27 months (21 – 46 months).

The post-operative results were:

The mean range of motion in flexion-extension was 130° (105° to 150°), while in pronation and supination was 74° (60°–80°).

Pain was evaluated with a visual analogue scale. Finally there was also a radiographic evaluation of the patients (that yielded six cases of loosening or osteolysis without any clinical manifestation)

Replacement of the radial head with the specific prosthesis leads to very satisfactory results when performed under specific indications.

To determine the effectiveness of Ilizarov external fixator in the treatment of complex fractures of the tibial plateau.

From July 2006 to April 2009, we treated 10 patients with the Ilizarov fixator. Six men and four women ranging in age from 31 to 70 (mean age 56.3 years) were evaluated. All patients were preoperatively evaluated with Computed Tomography scans for better preoperative planning. Eight cases had fractures type VI according to Schatzker Classification and 2 cases type V.

In all patients fixation included pushing olive wires or simple wires and 2 to 4 frames. In 4 patients minimal invasive open reduction was performed with use of bone allograft. In 2 fractures, we combined the treatment with minimal internal fixation

There was no major complication trans- or postoperatively. The mean follow-up was 16 months (4–30). The mean hospitalization was 8 days and there were no cases of blood transfusion. Mobilization with no weight-bearing was immediately allowed, with partial weight bearing after 2 months and full weight bearing after 3 months. Three patients had minor pin tract complications. The average duration of external fixation was 120 days. All the fractures united and patients achieved full extension with more than 110 degrees of flexion.

Ilizarov circular fixation is an alternative method of treatment for these fractures when internal fixation is contraindicated due to trauma to the soft tissue, deficiency of bone stock, and bony comminution

Aggrecan is a major constituent of joint cartilage. A prominent feature in joint disease is loss of Aggrecan. The aim of this study was to assess the relation between the concentration of Aggrecan in the synovial fluid of knee joint and this of the peripheral blood in patients suffering from end stage knee osteoarthritis

37 postmenopausal women suffering from end-stage idiopathic knee osteoarthritis, scheduled to undergo Total Knee Arthroplasty (TKA), were enrolled in this study. Their mean age was 69.8 years (range: 49–81 years). The serum levels of Aggrecan were evaluated one day pre-operatively whether synovial fluid levels from fluid taken during the operation day.

Patients suffering from any endocrine disorder, rheumatoid or other secondary arthritis or any other disease that could interfere with the cartilage homeostasis were excluded from the study. Concentrations of aggrecan turnover were measured with appropriate assays.

Moderate correlation between serum and synovial fluid concentrations of aggrecan was revealed (r= 0, 337, p=0,197)

Serum levels of aggrecan may be related to the synovial concentration of Aggrecan in patients suffering from end stage knee osteoarthritis. The possible significant relationship between these markers may be of value in assessing cartilage degradation in patients with involvement of a single joint with a blood sample. However this correlation needs to be further investigated

Objective: The clinical significance of biochemical bone markers in the diagnosis and severity of Osteoarthritis remains still unknown. The relationship between biochemical bone turnover markers and commonly recognizable radiographic features of knee and hip osteoarthritis remains unclear.

Purpose: We evaluated the serum levels of Receptor Activator of Nuclear Factor-κB Ligand (RANKL), Bone-specific Alkaline Phosphatase (b-ALP), Osteocalcin and Osteoprotegerin in two groups of patients suffering from osteoarthritis of the Knee or Hip respectively, aiming to correlate these results with the radiographically assessed severity of the disease and the patients’ age. The results between the two groups were also compared.

Patients-Methods: Between March 2007 and February 2009, a total of 175 patients suffering from Knee or Hip Osteoarthritis were enrolled in the study. Following proper radiographic evaluation, the osteoarthritic changes of patients were graded by 3 orthopaedic surgeons according to the system of Kellgren and Lawrence; at the same time the serum levels of biochemical markers were determined.

Results: Osteoprotegerin was found to be positively correlated with age in both the Knee (r=0.376, p=0.000) and Hip (r=0.425, p=0.001) group, whether Osteocalcin was significantly correlated with the age in the group of Knee Osteoarthritis(r=0.218, p=0.02). No other significant correlation was noted between the serum level of markers and age of patients in both groups. There was not significant difference in the mean serum level of biochemical markers among patients belonging to each of the four different levels of severity of hip and knee OA. There was no significant impact of the type of Osteoarthritis, to the serum level of all biochemical markers.

Conclusions: Based on our results, it seems that none of the serum biochemical markers studied can be used (either independently or in combination with the others) as surrogates for radiographic imaging in Hip and Knee osteoarthritis.

Background: The clinical significance of bone turnover markers is well recognized, at least in several diseases affecting the bone metabolism. However, their clinical significance (if any) remains still unknown in patients undergoing Total Joint Arthroplasty (TJA). Changes in the levels of some markers have been reported in the early postoperative period after Total Hip Arthroplasty; however their exact postoperative course has not been clearly documented yet. In order to assess the clinical value of biochemical markers when trying to determine the fixation of orthopaedic implants, it is necessary to clarify their normal postoperative course.

The aim of this study was to extend the evaluation of the course of bone turnover markers over a longer period (12 postoperative months) following a TJA, and to assess the postoperative course for two of them (RANKL and Osteoprotegerin) for the first time.

Methods: The serum levels of RANKL, Osteocalcin, Osteoprotegerin and bALP were determined one day preoperatively and several times during the first postoperative year in patients suffering from idiopathic osteoarthritis that underwent total knee (n=23) and hip arthroplasties (n=24).

Results: There were statistically significant changes in the serum levels of all markers over time (p< 0,001). RANKL values initially increased and then gradually decreased. Following an initial decrease, Osteocalcin values continuously increased until the 2nd postoperative month and then continuously decreased. Osteoprotegerin initially increased, then decreased until the 4th postoperative month and then increased again reaching a peak 8 months postoperatively. Bone-specific ALP decreased until the 7th postoperative day. After that time it continuously increased, reaching a peak at the 8th month, and then it gradually decreased. There were no major differences in the postoperative course of all markers between the hip and knee arthroplasties.

Conclusions: The levels of all bone markers did not uniformly ‘return’ to their preoperative values one year postoperatively. A one-year period is not enough, when assessing an orthopaedic implant’s fixation with the use of bone turnover markers.

Introduction: Osteoporosis is one of the major diseases worldwide, affecting millions of elderly people, with severe economical and medical consequences. The most commonly used method for the determination of decreased bone quality is the assessment of Bone Mineral Density, measured by dual X-ray absorptiometry (DXA). However DXA is quantitative and not qualitative index of the bone structure.

The purpose of this study was to correlate the bone mineral density measured by DXA with the mechanical properties of the femoral neck.

Materials and Methods: Bone mineral density of the proximal femur of 30 patients (27 women, 3 men) undergoing total hip displacement was estimated by DXA. The average age of these patients was 63.7 years. Patients with sort femoral neck or previous surgeries in proximal femur were excluded from the study. After hip replacement bone samples (femoral head and neck) were frozen and stored at −60 °C.

A plane bone slice with 6mm thickness was sawed of femoral neck using a double cutting saw. The exact specimen dimensions were measured using a sliding calliper with high accuracy.

All bone specimens were destructively tested on a material testing machine, in order to determine the material properties (Young’s modulus and yield stress) of the samples. The maximum available compression load was 100 kN with a load rate of 10 kN/min. The operational parameters and experimental data were fully controlled and handled by a graphical software package. Finally all data were evaluated and statistically analyzed.

Results: A strong linear correlation of bone mineral density (T-score) with maximum failure load of samples was noted (R2=0.852). No significant differences in Young’s modulus values, was found between bone samples.

Conclusions: Bone mineral density measured by DXA, although has limitations, remain a strong predictor of bone strength in the femoral neck region.

Background: Little work has focused on the effect of formal bracing on the health-related quality of life (QOL) of affected adolescents

Aim: The aim of this comparative study was to assess the quality of life of adolescents with Idiopathic Scoliosis in relation with the duration of application of modified Boston brace, as a conservative treatment.

Methods: 91 adolescents, 10 to 18 years old with idiopathic scoliosis who were treated conservatively with modified Boston brace took part in this study. The mean daily time of brace application was over 12 hours. Adolescents with history of acute or chronic illness, surgical treatment, mental retardation, neuromuscular disease or other congenital anomaly were excluded from the research.

The adolescents were divided in two groups. In the first group (n=47) were included adolescents wearing the brace for over two years (mean time of application 3, 3 years) and the second group (n=44) included adolescents, which have been treated with Boston brace for less than two years (mean time of application 1, 2 years).

Every child completed a detailed questionnaire (SRS-22) concerning the evaluation of function, pain, self image, mental health and satisfaction with management. Both groups were comparable according to age and degrees of scoliotic curve.

Results: There was no statistical significant difference concerning the results in every domain of the questionnaire between both groups. However the results concerning mental health show tendency towards significance favoring the second group.

Conclusion: Mental health of adolescents with Idiopathic Scoliosis wearing modified Boston brace needs to be further investigated.

Background and Objectives: It has been extensively discussed that there is a lowering effect of Replacement Therapy on lipids and lipoproteins. Recent hypotheses relate the lipids and osteoporosis. Thus, there is a possibility that hormone therapy improves osteoporosis not only via direct effect of estrogens on bone tissue, but also via lowering the lipids that may have detrimental effect on bone tissue. The aim of this study was to assess the effect of various regimens of hormone therapy on lipids and osteoporosis and the correlation between lipids and osteoporosis under given hormone treatment.

Methods: Three hundred and thirty five women (n=335) participated in this open study and were assigned to receive orally (a) CEE (n=29), (b) Tibolone (n=75), (c) CEE/MPA (n=57), (d) E2/NETA (n=72), (e) raloxifene (n=64) and (f) no therapy (control) (n=68) for at least 12 months. At baseline and 12 months blood samples were taken and analyzed for lipids and lipoproteins (total cholesterol, triglycerides, HDL, LDL, Lipoprotein (a), Apolipoprotein-A1, Apolipoprotein–B). At baseline and 12 months DEXA was also performed for the measurement of BMD of the lumbar spine.

Results: In the unopposed estrogen group (CEE) most of the variables were negatively connected with osteoporosis and BMD, but none of them were statistically significant. In the raloxifene group similar features were observed, but only LDL reached statistical significance (p=0.0031). In the tibolone group almost all variables were negatively correlated with osteoporosis and BMD, but again only LDL reached statistical significance (p=0.038). In the E2/NETA group most variables were negatively correlated with osteoporosis and BMD, but none reached statistical significance. In the CEE/MPA group all of the variables were negatively correlated with BMD and osteoporosis, but statistical significance was reached by total cholesterol, LDL and Lp(a) (p=0.008, 0.007, 0.047 respectively).

Conclusion: In this study it has been observed that there is a trend in almost every medication group towards an inverse correlation between lipids and BMD. The effect is more prominent in the tibolone, raloxifene and, mainly, in the CEE/MPA group. The greater effect was observed from the point of the lipids, in the LDL variable group. It is very important to clarify whether these findings could be extrapolated at orthopaedic trauma research providing thus a novel explanation for the aetiology of atrophic non unions in patients with compromised vascular function either locally or systematically.

Background: There are several methods to reduce anterior shoulder dislocations but only few studies compare the efficacy, safety and reliability of the different techniques. As a result, deciding which technique to use is seldom based on objective criteria. Aim of this prospective, randomized study is to introduce a new method of reduction of the anterior dislocation of the shoulder (“Fares”) and to compare it with the “Hippocrates” and “Kocher” methods, as far as its efficacy, safety and intensity of the pain felt by the patient during the reduction, are concerned.

Methods: Between September 2006 and June 2008, a total of 154 patients suffering from acute anterior shoulder dislocation (accompanied by a fracture of the greater tuberosity or not) were enrolled in the study. Patients were randomly assigned to one of the three study groups (“Fares”, “Hippocrates” and “Kocher”) and underwent reduction of their dislocation performed by first and second-year residents orthopaedic surgeons. A Visual Analogue Scale (VAS) was used to determine the intensity of the pain felt during reduction.

Results: The groups were statistically comparable (age, male/female ratio, mechanism of dislocation, mean time interval between injury and first attempt of reduction). Reduction was achieved with the “Fares” method in 88.6%, with the “Hippocrates” in 72.5% and with the “Kocher” in 68% of the patients. This difference was statistically significant, favoring the “Fares” method (p=0.033). The mean duration of the reduction (p=0.000) and the mean reported by the patients VAS with the “Fares” method (p=0.000) were also statistically significantly lower than those of the other methods. No complications were noted in any group.

Discussion: The “Fares” method was statistically proven to be a significantly more effective, faster and less painful method of reduction of the anterior shoulder dislocation, when compared with the “Hippocrates” and the “Kocher” methods. It is easily performed by only one physician, it is applicable both to anterior shoulder dislocations and fractures-dislocations and it is not more morbid that the other two methods.

Background: Hip fractures in the elderly have epidemic character. Although hip fractures have been considered as a single, homogeneous condition, there are two major anatomic types of proximal femoral fractures: intertrochanteric and femoral neck.

Aim: The purpose of our study is determining if patients suffering from these two types of hip fracture have different characteristics. Are demographics predictor factors of the type of hip fracture following fall in the elderly?

Patients and Methods: A retrospective study of patients admitted to a tertiary referral hospital for a hip fracture between 2003 and 2007 was conducted A total of 652 patients participated in the study, aged between 64–97 years old. 159 patients were men and 493 women.

Patients were divided into two groups according to the type of hip fracture. Group 1 included 299 patients with subcapital fractures, 61 men and 238 women and the second group 353 patients with intertrochanteric fractures, 98 men and 298 women. Patients’ demographics concerning age, sex, weight, height on admission at the hospital were compared between groups.

Results: The mean age (79± 9,4) of the patients with intertrochanteric fracture was statistically significant greater(Mann-Whitney test, p=0,001) than this of the patients with femoral neck fractures (76± 11,5).The sex ratio between the two groups seem to be significant different (x2 test, p=0,029) However following stratification of the data the effect of sex on the type of fracture disappeared. Mean height (Mann-Whitney test, p=0,765) and weight (Mann-Whitney test, p=0,448) did not differ significantly between the two groups. The mean time of hospitalization for the group of intertrochanteric fractures was significantly greater than this of the subcapital group(Mann-Whitney test. p=0,001).

Conclusions: It appears that intertrochanteric fracture patients have intrinsic factors (older age and consequently poor health) impacting upon their risk of fracture and ability to recover. Differences in patient characteristics and sequelae do exist between femoral neck and intertrochanteric hip fracture patients that impact upon recovery. However somatometric characteristics as height and weight did not differ significantly between the two types of fractures.

Introduction: Aim of this prospective study was the evaluation of the impact of TKA on the serum level of I-PTH, as continuously elevated levels of the latter may potentially play a negative role in an orthopaedic implant’s incorporation process.

Methods: The study-group was formed by 119 post-menopausal women suffering from end-stage idiopathic knee osteoarthritis scheduled to undergo TKA. Another 110 women that underwent elective non-orthopaedic operations were used as a control-group. The serum levels of I-PTH, Ca, P & creatinine were evaluated and the clearance of creatinine was calculated one day preoperatively and on the seventh postoperative day. Patients with abnormal preoperative values, suffering from endocrinopathies, rheumatoid or other secondary arthritis, osteoporosis or diseases interfering with bone homeostasis, as well as patients receiving medication affecting bone metabolism, were excluded. None had suffered any fracture or underwent any orthopaedic operation during the 36 months prior to her enrollment.

Results: The two groups were statistically comparable [age (p=0.72), weight (p=0.43), duration of menopause (p=0.31), serum creatinine level (p=0.49), creatinine clearance (p=0.74), preoperative serum I-PTH value (p=0.67)]. Sixteen patients of the study- (13.4%) and one of the control-group had abnormally elevated post-operative I-PTH values. Further analysis showed a statistically non-significant trend towards decrease in the post-operative I-PTH values of the study-group (p=0.16) compared with the control-group’s results were the I-PTH values remained statistically unchanged (p=0.55). No statistically significant difference was found in the postoperative serum I-PTH values between the two groups (p=0.21). The patients’ weight (p=0.76), age (p=0.77), serum creatinine (p=0.92) and creatinine clearance (p=0.96) did not have a statistically significant impact on the observed alteration of I-PTH values after TKA (study-group).

Discussion/Conclusion: The serum levels of I-PTH slightly decrease following TKA. This may attributed to the necrosis or apoptosis initiated immediately after implantation, leading to increased bone resorption and increased serum calcium concentrations that may well decrease the endogenous PTH production. Another possible explanation is the temporary immobilization of the patients undergoing TKA. A substantial number of our study-group’s women had abnormally elevated post-operative I-PTH values. Regardless of what actually caused it, the negative impact of continuously elevated PTH on bone formation, may interfere with the implant’s incorporation procedure, hence the evaluation of serum I-PTH before and after TKA is strongly recommended.

Background: The relation between Adolescent Idiopathic Scoliosis (AIS) and exercising is rather ambiguous. The latter has often been considered both as a therapeutic means as well as a causative factor of the former. Aim of this cross-sectional case-control study was the assessment of the incidence of AIS among athletes and non-athletes in order to determine whether athletic activities play a potential role (positive or not) in the development of AIS.

Methods: A group of 2387 adolescents (1177 boys and 1210 girls) was evaluated. Their mean age was 13.4 years (range:12–15 years). All patients completed a detailed questionnaire concerning personal, somatometric and secondary sex characteristics, type, duration and character of daily performed physical activities and existing cases of AIS among their relatives. The patients were classified into 2 groups according to their answers; ‘athletes’ and ‘non-athletes’. The 2 groups were statistically comparable as far as age, height, weight, onset of menstruation and prevalent extremity were concerned. All children underwent physical examination by 3 orthopaedic surgeons that were unaware of their level of athletic activities. Children considered, by all examiners, to be suspicious of suffering from scoliosis underwent further radiographic evaluation.

Results: One hundred and seventy seven children (66 boys and 111 girls) were considered as suspicious; in 99 cases (athletes: 48, non-athletes:51) AIS was radiographically confirmed. No statistically significant difference was found between athletes and non-athletes adolescents (p=0.927), athletes and non-athletes boys (p=0.888) and athletes and non-athletes girls (p=0.804), as far as the prevalence of AIS was concerned. There was also no statistically significant difference between male athletes and non-athletes (p=0.899) and female athletes and non-athletes (p=0.311) as far as the mean value of the Cobb angle of the main scoliotic curve was concerned.

Conclusions: This study’s results show that systematic exercising is not positively or negatively associated with a higher or lower incidence of AIS. Furthermore, actively participating in sports activities doesn’t seem to correlate with the degree of the main scoliotic curve either.

Introduction: Parathyroid hormone (PTH) is a major regulator of bone metabolism. Continuously elevated levels of PTH activate osteoclasts, whereas its intermittent administration principally induces osteoblastic activity. There is increasing evidence that intermittent treatment with PTH may enhance the early fixation of orthopaedic implants. Aim of this study was the evaluation of the impact of Total Knee Replacement (TKR) on the serum level of Intact-Parathyroid Hormone (I-PTH), as continuously elevated levels of the latter may potentially play a negative role in the implant’s incorporation process.

Methods: During a period of 29 months, one hundred and nineteen postmenopausal women suffering from end-stage idiopathic knee osteoarthritis, scheduled to undergo TKR, were enrolled in this prospective study. Their mean age was 69.8 (±6.01) years. The serum levels of I-PTH, Calcium, Phosphorus & Creatinine were evaluated and the clearance of creatinine was calculated one day pre-operatively and on the seventh post-operative day. Patients with abnormal preoperative values were excluded from the study. Furthermore, patients suffering from any endocrine disorder, rheumatoid or any other secondary arthritis, osteoporosis or any other disease that could interfere with their bone homeostasis as well as patients receiving medication affecting bone metabolism, were also excluded from the study. None had suffered any fracture or underwent any orthopaedic surgical operation during the 36 months prior to their enrollment.

Results: Sixteen patients (13.4%) had abnormally elevated post-operative I-PTH values. However, statistical analysis revealed a statistically significant trend towards decrease in post-operative I-PTH values (p=0.018). The weight (p=0.763), age (p=0.776), serum creatinine level (p=0.922) and creatinine clearance of the patients (p=0.963) did not have a statistically significant impact on the observed alteration of I-PTH values after TKR.

Discussion and Conclusion: The serum levels of I-PTH seem to decrease following a TKR. This is more or less expected, as immediately after implantation, bone cells adjacent to the implant are likely to be dead due to necrosis or apoptosis. The latter is a strong stimulus for bone resorption that probably leads to increased serum calcium concentrations that may well decrease the endogenous PTH production. Another possible explanation could be the temporary immobilization of the patients undergoing TKR. However, a substantial number of women had abnormally elevated post-operative I-PTH values. Regardless of what actually caused that increase, the negative impact of continuously elevated PTH on bone formation, may interfere with the implant’s incorporation procedure, hence the evaluation of serum I-PTH before and after TKR is strongly recommended.

The use of polymethylmethacrylate (PMMA) bone cement loaded with antibiotics has become increasingly common in orthopaedic surgery. However, bacterial resistance in antibiotics is an increasing and emerging problem. PMMA bone cements containing different antibiotics, such as gentamicin plus vancomycin may be effective in prevention and treatment of infections (particularly from MRSA and MRSE).

The purpose of this study was to determine the in vitro elution characteristics of gentamicin and vancomycin when combined in acrylic cement.

Three groups of ten cement disks were prepared. Group I (control group) contained 0.5g of gentamicin per 40-g packet of Palacos-R+G powder. Group II contained 0.5g of gentamicin and 1g of powdered vancomycin and group III contained 0.5g of gentamicin and aqueous solution of vancomycin. Each cement disc (25mm x 20mm) was immersed in a 50-mL bath of normal saline at 37oC. Samples were taken at specific sampling intervals (1, 3, 7, 15, 30, 60, 90, 120, 150, 180 days). Antibiotic concentrations were measured using fluorescence polarisation immunoassay.

With regards to gentamicin release, high but rapidly decreasing antibiotic levels were detected within the first week and low concentration after the first month. Samples from Group II eluted significantly more gentamicin (120%–20% during the first month). The influence on the gentamicin release was significant but minor when aqueous solution of vancomycin (Group III) was added. With regards to vancomycin release, high antibiotic levels were detected within the first 3 days and low concentrations after the first week. Cement samples from Group II eluted significantly more antibiotic in comparison with samples from Group III.

Bone cements loaded with combinations of gentamicin and vancomycin are more effective in releasing gentamicin than bone cements with gentamicin as a single drug. Powdered vancomycin in cement samples has better elution characteristics in comparison with aqueous solution of vancomycin.

Introduction. This prospective cohort study aimed at the assessment of the incidence of indolent SH among otherwise ‘healthy’ and symptoms’ free postmenopausal women suffering from primary KOA.

Methods. During a period of 23 months (November 2004 – Sepetember 2006), two hundred and forty-two postmenopausal women suffering from primary KOA were enrolled. None of them had suffered any osteoporotic fracture, received any anti-osteoporosis treatment or suffered from any disease interfering with their bone mass/quality. The serum levels of Intact-Parathyroid Hormone (I-PTH), Calcium and Phosphorus were evaluated and Creatinine Clearance was calculated. The latter was performed in order to determine a possible relation between the patients’ renal function and the I-PTH level.

Results. The patients’ mean age was 70,20 years (range: 49–81). The years that had passed since their menopause ranged from 7 to 31 (mean of 18,7 years). The patients were divided into three groups according to their age: Group A (n=41) age < 64 years, Group B (n=140) age 65–74 years and Group C (n=61) age > 75. The overall incidence of SY in all three groups was 35,95% (87 out of 242 patients). Group C patients were most likely to suffer from SY (25 out of 61 patients or 40,98%). The I-PTH values of Group A patients were normal in 27 out of 41 patients (68,85%) and of Group B in 92 out of 140 patients (65,71%). One group B patient suffered from Primary Hyperparathyroidism. No statistically significant relation between the patient’s renal function and the I-PTH level was found.

Discussion/Conclusion. SH appears to be a ‘silent’ epidemic among elderly postmenopausal women. According to our results, women 75 years-old and older are most likely to suffer from SY. One of the main reasons for that seems to be the insufficient calcium and/or vitamin D intake. It is our belief that anti-osteoporosis diagnosis and treatment modalities should be focused on this group of patients.

Introduction: The use of polymethylmethacrylate (PMMA) bone cement loaded with antibiotics has become increasingly common in the treatment of infected knee and hip arthroplasties and also as prophylaxis in primary joint replacement. However bacterial resistance in antibiotics is an increasing and emerging problem. PMMA bone cements containing different antibiotics, such as gentamicin plus vancomycin may be effective in prevention and treatment of infections (particularly from MRSA and MRSE). The purpose of this study was to determine the in vitro elution characteristics of gentamicin and van-comycin when combined in acrylic cement.

Material and methods: Three groups of six cement disks were prepared. Group I (control group) contained 0.5g of gentamicin sulphate per 40-g packet of Palacos-R+G powder. Group II contained 0.5g of gentamicin sulphate and 1g of finely powdered vancomycin and Group III contained 0.5g of gentamicin sulphate and aqueous solution of vancomycin (containing 2mL water for injection and 1g vancomycin). All discs were prepared using vacuum mixing technique. Each cement disc (25mm diameter × 20mm thick) was fully immersed in a 50-mL bath of normal saline at 37o C temperature in a covered beaker. At specific sampling intervals (1, 3, 7, 15, 30, 60, 90, 120, 150, 180 days) the discs were removed and placed in fresh 50 ml bath for 24 hours. Then a 2 mL sample of each solution was taken. Samples were frozen at −60° C until they were analyzed. Gentamicin and vancomycin concentrations were measured using fluorescence polarization immunoassay.

Results: With regards to gentamicin release, high but rapidly decreasing antibiotic levels were detected within the first week, resulting in an almost steadily low concentration by the end of the first month. Cement samples eluted significantly more gentamicin (120%-20% during the first month) when powdered vancomycin (Group II) was added. The influence on the gentamicin release was significant but minor when aqueous solution of vancomycin (Group III) was added (40%-20% during the same period).

With regards to vancomycin release, high antibiotic levels were detected within the first 3 days and low concentrations after the first week. Cement samples from Group II eluted significantly more antibiotic (80%–100%) in comparison with samples from Group III during the first days.

Gentamicin and vancomycin are detectable in measurements at 150 and 180 days samples.

Conclusions: Bone cements loaded with combinations of gentamicin and vancomycin are more effective in releasing gentamicin than bone cements with gentamicin as a single drug. The presence of powdered vancomycin in cement samples has major influence on the total gen-tamicin release in comparison with cements containing aqueous solution of vancomycin.

Introduction: Infections with multiresistant bacteria have become a serious problem in joint arthroplasty. Vancomycin and teicoplanin showed high effectiveness against multiresistant bacteria as methicillin-resistant S.epidermidis (MRSE) and methicillin-resistant S.aureus (MRSA).

Objective: The purpose of the present study was to determine the mechanical properties of Palacos R+G cement (containing gentamicin) mixed with:

i) powdered vancomycin or teicoplanin,

Material and methods: Five groups of ten cements specimens were prepared. Group I (control group) consisting of Palacos-R+G cement samples (contained 0.5g of gentamicin sulphate). Group II consisting of Palacos-R+G cement mixed with 1g of finely powdered vancomycin. Group III contained 400mg powdered teicoplanin. Group IV cement samples contained aqueous solution of vancomycin (2mL water for injection plus 1g vancomycin) and Group V contained aqueous solution of teicoplanin (2mL water for injection plus 400mg teicoplanin). All cement specimens were prepared using vacuum mixing technique. In order to examine the mechanical properties of the specimens (25mm diameter × 20mm height), impact and compression tests were applied. The impact test is a well-established method for the characterization of materials’ fatigue properties, as well as of creep behavior determination in case of porous materials. The size of the produced impression after a certain number of impacts reveals the material strength. Furthermore, the compression resistance, i.e. the Young’s modulus and the yield strength are properties that can be calculated by the compression tests.

Results: The compression tests showed that the specimens from Group III (containing 400mg of teicoplanin) had overall better mechanical properties, having approximately 10% higher Young’s modulus in comparison with specimens from Group II (containing van-comycin) and specimens from Group III (control group). Yield strength had no significant difference between the three groups. The impact test revealed a corresponding tendency, with the specimens containing 400mg of teicoplanin having the smaller impression (increased fatigue strength) when compared with specimens from the other groups.

With regards to samples from Groups IV and V (aqueous solutions of antibiotics) mechanical properties were significant deteriorated in comparison with cement samples from the other groups.

Conclusions: The experimental data showed that the addition of 400mg teicoplanin in Palacos R+G bone cement had better mechanical properties compared with addition of 1g vancomycin or than Palacos R+G cement with gentamicin as a single drug.

Aqueous solutions of antibiotics must not be added to the bone cement because they dramatically impair mechanical properties of the cement.

Background: Caudal extradural steroid injection is an alternative method of treating patients with chronic low back pain and sciatica.

Aim: The purpose of our study is determining the effectiveness of the caudal extradural steroid injection in patients with severe chronic low back pain and sciatica.

Patients – Methods: A total of 158 patients with severe and chronic low back pain and sciatica participated in the study, aged 23–78 years old. 86 patients were men and 72 women.

Patients were divided into two groups according to the injected drug. Group 1 or the injected group (n=91) received a caudal extradural injection (CEI) that consists of 12 to 15 ml of 2% xylocaine together with 1 ml of Betamethasone Dipropionate and Betamethasone phosphate. Group 2 or the placebo group (n=52), received a caudal extradural injection that consists of 6–8 ml of 2% xylocaine mixed with 6–8 ml of water for injection. The mean duration of symptoms was comparable between the two groups.

In order to estimate the degree of recovery from symptoms, all patients answered a specific questionnaire. The Oswestry Disability Index Questionnaire (ODI) was answered by all patients on the first day of clinical examination, and on different follow-up periods after caudal injection.

The straight leg-raising test was evaluated in all patients at the same follow – up periods.

Results: Recovery from symptoms and a decrease in the O.D.I score after the CEI was observed in both groups. However the mean ODI score of the injected group was statistically significant lower than this of control group for a period until one month after the injection (p < 0,001, Wilkoxon Signed Ranks test). Also the mean improvement time of positive SLR test in the injected group was statistically significant lower than this of control group (log rank test, p = 0,019)

Conclusions: The caudal extradural steroid injection is a reasonable non-surgical therapeutic option among patients with severe chronic low back pain and sciatica. It offers pain relief to patients who do not respond to prolonged conservative therapy, or who refuse surgery. It can easily be performed in the outpatient clinic.

The aim of this biomechanical study was to investigate the role of the dorsal vertebral cortex in transpedicular screw fixation. Moss transpedicular screws were introduced into both pedicles of each vertebra in 25 human cadaver vertebrae. The dorsal vertebral cortex and subcortical bone corresponding to the entrance site of the screw were removed on one side and preserved on the other. Biomechanical testing showed that the mean peak pull-out strength for the inserted screws, following removal of the dorsal cortex, was 956.16 N. If the dorsal cortex was preserved, the mean peak pullout strength was 1295.64 N. The mean increase was 339.48 N (26.13%; p = 0.033). The bone mineral density correlated positively with peak pull-out strength.

Preservation of the dorsal vertebral cortex at the site of insertion of the screw offers a significant increase in peak pull-out strength. This may result from engagement by the final screw threads in the denser bone of the dorsal cortex and the underlying subcortical area. Every effort should be made to preserve the dorsal vertebral cortex during insertion of transpedicular screws.