Background

An increased incidence of periprosthetic osteolysis, resulting in loss of biologic fixation, has been recently reported in contemporary THAs with low-carbide metal-on-metal compared to metal-on-polyethylene couple bearings. A hypersensitivity reaction due to Co and Cr debris is reported as a potential cause for failure of THAs with high-carbide bearings, but there are no evidence-based data for this reaction in low-carbide metal-on-metal bearings.

Most studies on LBP have focused on adults although many investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years.

688 students aged 16± 1 years from 5 randomly selected high schools participated in this multifactorial study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics.

LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts.

LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents.

Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity

Study design: Prospective multifactorial study on low back pain (LBP) in adolescents.

Background data: Most studies on LBP have focused on adults although may investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical and behavioral factors have associated with non-specific LBP in adolescents. To our knowledge no previous study has investigated using advanced statistics all previously reported parameters together with psychological and psychosocial factors on LBP in adolescents aged 15–19 years.

Material and Methods: 688 students aged 16± 1 years from 5 randomly selected high schools participated in this study and completed a questionnaire containing questions on daily activity, backpacks carrying, psychological and psychosocial behavior. Anthropometric data as well biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics.

Results: LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP(0.002), physical activity(P< 0.001), physician consultation(P=0.024) and depression (P< 0.001) Gender-related differences were shown regarding LBP intensity(P=0.005) and frequency(P=0.013), stress(P< 0.03), depression (P=0.005) and nervous mood(P=0.036) in favor of male students. Male adolescents had continuously energy (P=0.0258) and were calm (P=0.029) in contrast to female counterparts.

Discussion: LBP was gender-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood and low energy have more LBP than boys that makes physician consultation for LBP more common in female adolescents.

Conclusion: Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity.

Objective. To evaluate the outcomes of the treatment of acute thoracolumbar burst fractures by transpedicular balloon kyphoplasty with Calcium phosphate cement and posterior instrumented fusion.

Methods: Twenty-three consecutive patients (average age 48 years) who sustained thoracolumbar A3-type burst fracture with or without neurologic deficit were included in this prospective study. Twenty-one out 23 patients had single fractures and the left 2 had each one additional A1 compression contiguous fracture. On admission 5(26%) out 23 patients had neurologic lesion (5 incomplete, one complete). Bilateral transpedicular balloon kyphoplasty was performed with quick hardening calcium phosphate cement to reduce segmental kyphosis and restore vertebral body height and supplementary pedicle screw instrumentation (long including 4 vertebrae for T9-L1 fractures and short (3 vertebrae) for L2 to L4 fractures. Gardner kyphosis angle, anterior and posterior vertebral body height ratio and spinal canal encroachment were calculated pre–to postoperatively.

Results: All 23 patients were operated within two days after admission and were followed for at least 24 months after index surgery. Operating time and blood loss averaged 70 minutes and 250 cc respectively. The 5 patients with incomplete neurologic lesions improved by at least one ASIA grade, while no neurological deterioration was observed in any case. Overall sagittal alignment was improved from an average preoperative 16o to one degree kyphosis at final follow up observation. The anterior vertebral body height ratio improved from 0.6 preoperatively to 0.9 (P< 0.001) postoperatively, while posterior vertebral body height was improved from 0.95 to 1 (P< 0.01). Spinal canal encroachment was reduced from an average 32% preoperatively to 20% postoperatively. No differences in preoperative values and postoperative changes in radiographic parameters between short and long group were shown. Cement leakage was observed in 4 cases: three anterior to vertebral body and one into the disc without sequalae. In the last CT evaluation, continuity was shown between calcium phosphate and cancellous vertebral body bone. Posterolateral radiological fusion was achieved within 6–8 months after index operation. There was no instrumentation failure or measurable loss of sagittal curve and vertebral height correction in any group of patients.

Conclusions: Balloon kyphoplasty with calcium phosphate cement secured with posterior long and short fixation in the thoracolumbar and lumbar spine respectively provided excellent immediate reduction of posttraumatic segmental kyphosis and significant spinal canal clearance and restored vertebral body height in the fracture level in an equal amount both in short and long instrumentation.

Several methods of surgical treatment for pyogenic spondylitis have been reported including anterior approach, staged and simultaneous anterior decompression and posterior stabilisation. The use of anterior implants in the presence of infection presents still a challenge for spine surgeons.

Retrospective analysis of the clinical and radiological outcome of patients suffering from pyogenic spondylitis of the cervical and lumbar spine necessitating surgical treatment for intractable pain, instability and neurologic impairment.

Seventeen patients with spondylitis associated or not with paravertebral abscess were treated by one stage surgery (first: anterior decompression and placement of titanium mesh cage, filled with autologous iliac bone graft; second: posterior transpedicular instrumentation and fusion). The age of the patients was 54 ±15 years. Most of the patients had systematic problems such as lung tuberculosis, hepatic cirrhosis, diabetes mellitus or chronic renal failure. Patients were evaluated before and after surgery in terms of pain and neurological level, sagittal spinal balance and radiological fusion. All 17 patients were followed for 45 months.

Average duration of both surgeries was 4.5 hours. The VAS score improved from 7 (preoperatively) to 2 (postoperatively). The correction of the segmental kyphotic deformity was 6o, without loss of correction or cage migration or instrumentation failure. All patients with incomplete neurologic impairment improved postoperatively. There was neither migration of mesh cage nor posterior instrumentation failure at the follow up observation. There was an approach-related abdominal hernia.

This clinical study showed that patients with cervical and thoracolumbar osteomyelitis necessitating surgery for certain indications can successfully undergo instrumented combined, one-stage, same-day surgery. The presence of the mesh cage anteriorly at the site of infection had not negative but beneficial influence on the course of infection healing, and it additionally stabilised the affected segment, maintaining sufficient sagittal profile.

Background. Balloon kyphoplasty has been established as an effective minimal invasive method to treat vertebral fractures of osteoporotic and pathologic etiology.

Objectives. Comparative analysis of the clinical and radiographic outcomes of balloon kyphoplasty for treatment of osteoporotic and pathologic vertebral fractures.

Study design. Prospective comparative study.

Materials-Methods. Twenty five patients (14 women and 11 men) aged (average + SD) 73 + 8 years (range 52–83 years) with vertebral fracture were treated with kyphoplasty and were sampled into three groups: 14 patients (Group A) suffered from osteoporotic fractures and underwent percutaneous kyphoplasty, 5 patients (Group B) suffered from fractures caused from malignancy were treated with percutaneous kyphoplasty, and 6 patients (Group C, hybrid) who underwent combined operation (open kyphoplasty plus instrumented fusion). These patients underwent 25 operations to treat 38 vertebral fractures located between T11 and L5. Preoperative and postoperative radiographs were compared to calculate the changes of vertebral body height ratio (AVBHr, PVBHr) and Gardner kyphotic deformity angle. Sagittal spine alignment was analyzed on whole spine standing radiographs. The VAS, the Oswestry Disability Index (ODI) and the SF-36 surveys were used to evaluate the clinical results. The average time of follow-up was 31.5 + 7 months (range 25–40 months). The average preoperatively SF-36 score (Domain Bodily pain) was 8+ 16, The VAS was 9+1.3 while the ODI was 28+ 17.

Results. The average SF-36 (Bodily Pain) score did not significantly differ among the groups and was improved postoperatively to (average, SD) 40+14. VAS improved postoperatively in an similar way in all three groups to 4+1.4 and the ODI was improved in all three groups to 49+ 17, without significant differences among groups. The AVBHr improved significantly only in group A (p=0.01), while there was no change in PVBHr in any group. The Gardner angle improved significantly in groups A (p=0.006) and C (p=0.05) respectively.

Discussion. The inflatable bone tamp placed percutaneous or open in combination with spinal instrumentation was efficacious in the treatment of osteoporotic and pathologic vertebral fractures. Kyphoplasty alone or as hybrid was associated with early clinical improvement of pain and function in the treatment of painful pathologic compression fractures, as well as with reduction of Gardner angle.

Background data. The clinical outcome of decompression and posterolateral spinal fusion for patients with degenerative lumbar spinal stenosis may be influenced by a variety of pathophysiologic factors. Among them, sagittal balance of the spine has gained new interest regarding its correlation with low back pain following lumbar spine surgery.

Objectives. To study the effect of sagittal spinal alignment on low back pain in patients operated for degenerative lumbar spinal stenosis.

Study design. Multifactorial analysis.

Materials and Methods. In this prospective randomized comparative study 45 consecutive patients were included, who underwent decompression for symptomatic degenerative lumbar spinal stenosis and two-, three- or four levels posterior transpedicular fixation with three instrumentations of different stiffness (dynamic, semirigid and rigid) plus posterolateral fusion. All patients were followed up for an average period of four-year radiologically and with SF-36 (domain Bodily pain) to investigate possible correlations between anthropometric parameters, stiffness and extension of instrumentation, roentgenographic sagittal balance, motion in adjacent free level and low back pain.

Results. Bodily pain scores improved with the time lapsed from index operation (P< 0.0001). As the distance of the apical lumbar vertebra from plumbline increased, bodily pain score improved significantly (P=0.0006). At the last observation following surgery patients had better Bodily pain score than that they had preoperatively (P=0.0001) and six months postoperatively (P< 0.0001) respectively. Patients, who received four levels instrumentation had higher Bodily pain score (P=0.0245) than their counterparts who received two levels instrumentation.

Discussion. Maintenance or even improvement of lumbar lordosis, instrumentation of three and four vertebrae, and time lapsed from index operation was associated with improvement of back pain. On contrary, patients’ age, gender, instrumentation stiffness, vertebral inclination, thoracic kyphosis and sagittal lumbar flexibility did not affect the surgical outcome regarding back pain in adult patients who underwent decompression and stabilization 2 to 4 levels for degenerative lumbar spinal stenosis.

Background: Recent studies have reported early periprosthetic osteolysis in patients who have been treated with a contemporary metal-on-metal total hip arthroplasty and suggested that metal hypersensitivity associated with an immunologic response to metal may be of etiologic importance. We evaluated the results and histologic findings in patients who underwent revision surgery for a failed contemporary metal-on-metal total hip arthroplasty.

Material and Methods: Two hundred and seventeen total hip arthroplasties (SL-Plus stem and Bicon-Plus cup) with a Sikomet metal-on-metal articulation were implanted in one hundred and ninety four consecutive patients and retrospectively reviewed at mean of 77 months postoperatively. Clinical follow up was performed with the Harris hip score and plain radiographic evaluation was performed. Histologic analysis was performed on the periprosthetic tissues of 14 hips that underwent revision arthroplasty.

Results: The mean Harris hip score improved from 45 preoperatively to 96 at final evaluation. Fourteen (6.4%) hips were revised: 9 for aseptic loosening, 2 for technical failure and three for septic failure. Histologic examination of the retrieved periprosthetic tissues from the eleven patients who underwent revision for aseptic loosening or technical failure showed microscopic metallosis and extensive lymphocytic and plasma cell infiltration around the metal debris. With an endpoint of removal of a component with aseptic loosening, endpoint survivorship was 93% for the stem and 98% for the cup respectively.

Conclusions: Our findings are in agreement with recent publications and support the possibility that periprosthetic osteolysis and aseptic loosening in hips with metal-on-metal articulation are possibly associated with hypersensitivity to metal debris. Prospective, comparative randomized long-term studies are necessary to determine the cause(s) of loosening of this particular articulation.

Introduction & Purpose of Study. The purpose of the present study was to evaluate the clinical, radiographic and histologic results with the Zweymueller total hip arthroplasty (THA) and metal-on-metal articulation. Material and Methods. Between 1994–2003, 380 patients received 415 third-generation Zweymueller-Plus THA with SL-stem and Bicon screw socket for hip osteoarthritis. Ten (5.15%) patients did not return for their last follow-up evaluation for reasons unrelated to their hip operation. This study reports on 217 THAs with follow up more than 60 months. The 217 THAs were implanted in 194 patients (143 women and 51 men), aged 55 ± 9 years, (25–70 years). The most common diagnosis for THA was primary osteoarthritis (48%) followed by secondary osteoarthritis due to developmental hip dysplasia (44%). Results. The follow-up was 77 ±17 months, (60 – 112 months). From the 217 THAs, 14 (6.4%) hips were revised for any reason; the socket in 5(2.3%) and the SL-stem in 9(4.1%) hips. The preoperative Harris hip score of 45±19 was improved to 96 ± 4 postoperatively. 95% of the patients were satisfied or very satisfied with the result of the operation. Revision was made in a total 14(4.6%) hips because of different reasons. The aseptic revision rate was 5%: 4(1.8%) Bicon cups and 7(3%) SL-stems were revised for aseptic loosening. The septic revision rate was 1.4% (3 THAs) and was due to Staph aureus. Periarticular ossification was observed in 32(17%) of the hips (5% Brooker grades III and IV), however without associated disability. The histological examination revealed mild metalosis (Mirra grades 1 and 2) in all revised hips. The cumulative survival for any reason (95% C.I.) was 90% (97% to 71%). The aseptic survival was 91% (97–72%) [95% CI); and specifically for the Bicon socket it was 98 % (100 to 92%); and for the SL-stem 93% (98% to 74%)[CI 95%]. The survival for the men and women was 78.9% and 94.4% respectively (log rank test: chi square P= 0.25). A significant, not statistically significant observation was that men showed lower survival for the stem than women (78.9 vs. 97.5%). Conclusion. This study showed that the medium-term results of Zweymueller total hip arthroplasty with metal-on-metal articulation were inferior particularly for the SL-stem to those obtained with the conventional Zweymueller total hip arthroplasty with polyethylene-ceramic articulation. This could be due either to allergic or mechanical (Sikomet Alloy) reasons.

Objectives: To investigate the influence of backpacks on the spine curves, shoulder level, trunk and back pain in schooladolescents.

Methods: 1263 students, aged 12 to 18 years, who carried backpacks over one or both shoulders to the school were asked for dorsal (DP) and/or low back pain (LBP). Kyphometer and Scoliometer were used to measure craniocervical angle (CCA), thoracic kyphosis, lumbar lordosis and shoulder level shift(BL) and biplane trunk deviations. Logistic and multinomial logistic analysis, t-test, Wilcoxon and chi-square tests were used for statistics.

Results: Backpacks decreased CCA (P< 0.001), and increased BL-shift(P< 0.001), and biplane trunk shift (P< 0.03). Girls suffer 6(P=0.001) times more from DP than boys. Students carrying backpacks asymmetrically suffer 3(P=0.035) and 5(P=0.014) more from DP and LBP respectively, than those symmetrically carrying. With increasing BMI decreases the possibility for DP at 10%(P=0.047) and increases at 10%(P=0.046) the possibility for LBP. With increase of BL-shift increases at 26%(P=0.024) DP. With increase of coronal trunk shift increases DP(P=0.011) and LBP(P=0.057). With increasing of sagittal loaded trunk shift increases LBP(P=0.065). In holidays: Girls suffer 3.2 times(P=0.050) more than boys in holidays; Asymmetrically carrying increases 8 times(P=0.006) back pain; Longer backpack carrying increases 2%(P=0.047) back pain; With shift of BL increases at 29.5%(P=0.042) back pain; With increase of coronal trunk shift increases 2.3 times(P=0.054) back pain. From high pain suffer: Girls suffer four times(P=0.015) more than boys; Asymmetrically backpack carrying increases four times(P=0.015) high pain; Increase of frontal trunk shift is associated by high pain three times (P=0.005) more.

Conclusion: Backpack carrying resulted in a forward lean of the upper trunk, and a decrease of cervical lordosis. Asymmetrically backpack carrying forced adolescents to rise the backpack bearing shoulder and simultaneously to shift the upper trunk contralaterally. These changes seem statistically to increase the incidence of back pain in the school period and during the holidays, particularly in girls. It is recommended that schoolchildren carry backpacks symmetrically with two straps.

Purpose: Prospective randomized clinical and radiological study to compare the evolution of instrumented posterolateral lumbosacral fusion using either coralline hydroxyapatite(CHA), or iliac bone graft(IBG) in three comparable groups of patients.

Methods: 56 randomly selected adult patients with spinal stenosis were divided into three groups(A,B,C) included 17, 19 and 20 patients respectively and underwent decompression and fusion. The spines of Group A received IBG ; Group B IBG on the left side and CHA mixed with local bone and bone marrow on the right side; Group C CHA mixed with local bone and bone marrow bilaterally. The patients’s age was 61+11, 64+8 and 58+8 years for groups A, B and C respectively. SF-36, Oswestry Disability Index, and Roland-Morris surveys were used. Visual Analog pain Scale was used for pain. Roentgenograms (AP, lateral and oblique plus bending views) and CT-scans were used to evaluate the evolution of fusion. Two independent observers tested variability in evolution of the dorsolateral bony fusion 3 to 48 months postoperatively with the Christiansen’s and CHA resorption in Groups B and C.

Results: Intraobserver and interobserver agreement (r) for radiological fusion was 0.71 and 0.69 respectively, and 0.83 and 0.76 for evaluation of CHA resorption. There was no visible pseudarthrosis. Fusion was achieved one year postoperatively. CHA resorped 6 months postoperatively at the intertransverse spaces. Bone bridging started 3 months postoperatively in all levels posteriorly as well as between the transverse processes where IBG was applied. SF-36, Oswestry Disability Index, and Roland-Morris Score improved > 20 postoperatively in all groups. There was one pedicle screw breakage at the lowermost-instrumented level in group A and two in group C without pseudarthrosis. There was no deep infection. Operative time and blood loss were less in group C, while donor site complaints were observed in the patients of the groups A and B only.

Discussion & Conclusion: This study showed that autologous IBG remains the gold standard for posterior instrumented lumbar fusion to which each new graft should be compared. CHA was proven in this series not appropriate for intertransverse posterolateral fusion because the host bone in this area is little.

Aims: To investigate if coralline hydroxyapatite conduct bone formation in human spine. Methods: During revision surgery specimens were taken from the fusion mass from 13 patients, who received spinal instrumentation (Titanium alloy) and fusion with coralline hydroxyapatite. The age of patients at the time of revision surgery was 46±20 years. The time lapsed from the implantation of coralline hydroxyapatite (ProOsteon) was 11±11 months. The indication for revision was infection, pseudarthrosis, technical error, and pain related to hardware. The diagnosis for primary fusion was degenerative disease, spinal trauma and scoliosis. Coralline hydroxyapatite was applied on the posterior decorticated elements of the instrumented spine without any mixture with bone graft. Material from ten different places from the fusion mass was intraoperatively taken and the histological evaluation was made using the Hematoxylin-eosin histological stain. Results: There was a concentration of foreign-body like giant cells & development inflammatory granulomatous tissue around hydroxyapatite granules, which was gradually replaced by dense connective collagen tissue. Both inflammatory granulomatous and collagen tissue showed areas with foreign body reaction. In the cases, where bone has developed, the most initial finding was the presence of osteoblasts & apposition of osteoid in contact to hydroxyapatite granules. In a later phase, cancellous and lamellar bone has developed as a result of secondary ossification. Bone formation was observed in 11/15 cases. Conclusion: Coralline hydroxy-apatite conducts bone and osteoid formation around the implanted coralline hydroxyapatite granules in different areas of the human spine operated for different disorders.

Aims: To study the efþcacy of Texas Scottish Rite Hospital transpedicular screws versus laminar hooks in lumbar spine. Methods: 40 patients with unstable thoracolumbar fractures and spinal canal encroachment were randomly sampled into two groups: 20 patients received hooks in Òclaw conþgurationÒ in thoracic and lumbar spine (Group A), and 20 patients hooks in thoracic and transpedicular screws in the lumbar spine (Group B). Gardner kyphotic deformity; anterior vertebral body height (AVBH); Posterior vertebral body height (PVBH); and Spinal canal encroachment (SCE) were measured in roentgenograms and CT-scan. Results: All patients were followed for 52 months, (range, 42–71 months) postoperatively. Gardner angle was corrected at 45% and 48% with a loss of correction of 1.5û and 1û for Group A and B respectively. AVBH was corrected at 16% and 33% in Group A and B with loss of correction of 11% only in group A. PVBH was restored only in Group B at 3%, while the loss of correction was 4% and 1% for group A and B respectively. SCE was postoperatively decreased at 19% and 32% in group A and B respectively. On the latest evaluation there was an increase of SCE at 9% in group A, while it was furthermore decreased at 10.5% in-group B. All patients with incomplete neurologic lesions in-group A and B were postoperatively improved at 1.1 degrees and 1.7 degrees respectively. There was no screw failure, while there was two hook dislodgements in the thoracic spine (one in each group). There was neither pseudarthrosis nor neurologic deterioration in this series. Conclusions: The use of pedicle screws in the lumbar spine for stabilization of thoracolumbar injuries offers better correction of posttraumatic kyphotic deformity, restores and maintains better than hooks anterior and posterior vertebral body height of the fractured vertebra without loss of correction, and safeguard continuous remodeling of spinal canal resulting in increasing spinal canal clearance with time lapsed from operation.

Aim: Periprosthetic fractures are usually difþcult to be stabilized using plates and screws because of the presence of the underlying intramedullary stem, PMMA cement and thin periprosthetic femoral cortex. Modern techniques using cerclages and bands may be useful. Material & Methods: This study compares Ç in vitro È the mechanical performance of þve different osteosynthesis techniques applied on a oak femoral model obliquely oscillated to mimic a short oblique fracture: (a) double stainless steel wiring, (b) two 4.5 mm lag screws, © combination of one 4.5 mm cortical screw and one stainless steel wire, (d) one titanium cerclage CCG (Compression Cerclage Gudolf) combined with one 4.5 mm screw, and (e) double CCG Cerclage. The þve þxation constructs were subjected to a non-cyclic destructive axial compression and torsional loading. Results: The highest torque stiffness showed the double CCG and the double screw constructs, followed by and combination of CCG-screw and double wire constructs. The mode of failure in torque was a longitudinal crack close to screw tip and loosening of CCG and wire. The double screw, double CCG and screw- CCG constructs provided the highest stiffness in axial compressive forces. The mode of failure under compression was either loosening of CCG and wire or bending of the screw. Conclusions: This comparative study showed that double CCG can used in the treatment of oblique periprosthetic femoral fractures with the advantages of the simple technique, biocompatibility of titanium, no interference in modern imaging techniques and avoidance of stripping of muscles and degloving of bone surfaces as in platting often happens.

Aims: Asymmetry of the breasts in female adolescents may be linked with right convex thoracic scoliosis. This is a prospective comparative study of the internal mammary artery (IMA) with Color Doppler Ultrasonography (CDU) in female adolescents and controls. Methods: 20 female adolescents with right thoracic scoliosis and 16 comparable individuals without spine deformity were included in this study. Scoliosis curve, vertebral rotation and concave and convex rib-vertebra-angle (RVA) at three vertebrae close to apical were measured. IMA- lumen, cross sectional area, time average mean ßow and ßow volume per minute were measured with CDU in scoliotics and controls. Results: The reliability of CDU. was high and the intraobserver variability low (ANOVA, P=0.92–0.94). There was no difference in CDU-parameters of IMA between right and left side, as well as between scoliotics and controls. In scoliotics the right IMA- time average mean velocity increases with both RVAs one level above the apical vertebrae (P< 0.01), convex RVA one level below the apical vertebra (P< 0.05), and concave RVA (P< 0.01). The left IMA-time average increases with only the convex RVA one level above the apical vertebra (P< 0.05). IMA- ßow volume increases with the convex RVA one level above the apical vertebra (P< 0.05), while the right IMA-ßow volume increases furthermore with the apical RVA (P< 0.01) and concave RVA one level above the apical vertebra (P< 0.01). The concave apical RVA (P< 0.01) and concave RVA one level above the apical vertebra (P< 0.01) increases with left IMA cross sectional area. Conclusion: This study showed that anatomy and haemodynamic ßow parameters of IMA signiþcantly correlated with apical roentgen-ographic parameters. However, there was no evidence for side-difference in vascularity of the anterior thorax wall that could justify the previous theories for development of right thoracic scoliosis in adolescent females

Introduction-Aim: The fractures which occurred at the midshaft of the femur, in which there is a prosthesis, are difficult to stabilize using free screws or plates, because of the presence of the underlying intramedullary stem, PMMA cement and thin periprosthetic femoral cortex. Although the periprosthetic fractures are usually oblique with a big contact surface between the pieces of the fracture and with the datum of the intramedullary presence of the femoral stem of the prosthesis, which increases the stability, this study compares five different types of internal fixation a rather unstable «worst case scenario» oblique midshaft fracture of the femur.

Material & Methods: We compared «in vitro» the mechanical performance of five different ïsteosynthesis techniques applied on a oak femoral model obliquely oscillated to mimic a short oblique 60o fracture. We compared the following kind of osteosynthesis: (a) double stainless steel wiring, (b) two 4.5 mm lag screws, (c) combination of one 4,5 mm cortical screw and one stainless steel wire, (d) double CCG cerclage, and (e) one titanium cerclage CCG (Compression Cerclage Gudolf) combined with one 4.5 mm screw. The five fixation constructs were subjected to a noncyclic destructive axial compression and torsional loading.

Results: The highest torque stiffness showed the double CCG and the double screw constructs, followed by the combination of CCG-screw and double wire constructs. The mode of failure in torque was a longitudinal crack close to the screw tip and loosening of CCG and wire. The double screw, double CCG and screw-CCG constructs provided the highest stiffness in axial compressive forces. The mode of failure in compression was loosening of CCG and wire and bending of screw.

Conclusions: The advantages of using the CCG is the simple technique, biocomptability of titanium, no interference in modern imaging techniques and avoidance of stripping of muscles. The method with the CCG titanium band proved biomechanically so stable as the system with the double 4,5 mm screw and recommend an alternative solution for the osteosynthesis of the distal periprosthetic fractures of the femur, especially for the cases with periprosthetic osteoporosis.

Aim. The aim of this study is to estimate the medium-term results with the Zweymueller metal-on-metal THA in the osteoarthritis of the hip.

Material & Methods. A total of 266 consecutive patients, received 350 third-generation Zweymueller-SL total hip arthroplasties with metal-on-metal articulation for primary or secondary osteoarthritis. The age of the patients at the time of surgery was 55+9 years, (range 25–70 years). Seven (3%) patients did not return for their last follow-up evaluation and they excluded.

Results. The mean follow-up was 67 months (range 49–102 months). The preoperative Harris hip score was 45±19 and increased to 87±4 postoperatively. The invalidity of the patients was significantly improved postoperatively (p< 0.001). In all, 97% of the patients were satisfied or very satisfied with the result of the operation. There was no aseptic loosening noted in this series. Revision was done in 6 (1.8%) hips because of septic loosening (n=5, 1.5%) or technical error (n=1, 0.3%) during implantation. Dislocation of the prosthesis occurred in the early postoperative period in 2 (0.6%) hips because of technical errors during implantation. Periarticular ossification was observed in 30% of the hips (5% Brooker grades III and IV), but without associated disability. During revision surgery, no macroscopic metalosis could be identified in the newly formed hip joint membrane; how ever microscopic evidence for metalosis (Mirra grades 1 and 2) was seen in all revised hips. The survival for Zweymueller screw socket and stem 7.6 years after implantation was 99.4% and 96.8%, respectively.

Conclusion. The reasons of the loosening of Metal-on-Metal Zweymueller THA were the infection or the technical errors during implantation of the socket and nothing about the metal-on-metal articulation.

Previous investigations have postulated that the asymmetry of the breasts in female adolescents may be linked with the development of right convex thoracic scoliosis, although there is no correlation between breast asymmetry and curve type or scoliosis magnitude. This breast asymmetry is supposed to be linked with anatomic and functional asymmetry of the internal mammary artery that is the main supplier to the mammary gland. However, no measurements of anatomic and haemodynamic parameters of internal mammary artery have been made to justify or to reject the hypothesis of asymmetric blood flow volume to the breasts and costosternal junction in female adolescent scoliotics.

Twenty female adolescents with right thoracic scoliosis and 16 comparable female individuals without spine deformity were included in this study. Standing roentgenograms of the whole spine were made in all scoliotics to measure scoliosis curve, vertebral rotation and concave and convex rib-vertebra-angle at three vertebrae (apical, one level above and one below the apical vertebra). The Color Doppler Ultrasonography was used to measure at the origin of internal mammary artery its lumen diameter, cross sectional area, time average mean flow and flow volume per minute in scoliotics and controls and were compared each other. The roentgenographic parameters were compared with the ultrasonographic parameters in the scoliotics to disclose any relationship.

The reliability of color Doppler ultrasonography was high and the intraobserver variability low (ANOVA, P=0.92–0.94). There was no statistically significant difference in the ultrasonographic parameters of the internal mammary artery between right and left side in each individual as well as between scoliotics and controls. In scoliotics the right mammary artery time average mean velocity increases with the convex and concave rib-vertebra-angle one level above the apical vertebrae (P< 0.01), convex rib-vertebra angle one level below the apical vertebra (P< 0.05), and concave apical rib-vertebra angle (P< 0.01). The left internal mammary artery time average increases with only the convex rib-vertebra angle one level above the apical vertebra (P< 0.05). The right and left internal mammary artery flow volume increases with the convex rib-vertebra-angle one level above the apical vertebra (P< 0.05), while the right internal mammary artery flow volume increases furthermore with the apical concave rib-vertebra-angle (P< 0.01) and concave rib-vertebra angle one level above the apical vertebra (P< 0.01). The concave apical rib-vertebra-angle (P< 0.01) and concave rib-vertebra-angle one level above the apical vertebra (P< 0.01) increases with left internal mammary artery cross sectional area.

We concluded that anatomic and haemodynamic flow parameters measured at the origin of internal mammary artery are significantly correlated with apical rib-vertebra-angle in female adolescents suffering from right convex idiopathic thoracic scoliosis. This study did not find any evidence for side-difference in vascularity of the anterior thorax wall thus could not justify previous theories for development of right thoracic scoliosis in female adolescents.