Alexander Hadjipavlou

Occupational exposure from common fluoroscopic projections used in orthopaedic surgery

BACKGROUND Personnel assisting in or performing fluoroscopically guided procedures may be exposed to high doses of radiation. Accurate occupational dosimetric data for the orthopaedic theater staff are of paramount importance for practicing radiation safety. METHODS Fluoroscopic screening was performed on an anthropomorphic phantom with use of four projections common in image-guided orthopaedic surgery. The simulated projections were categorized, according to the imaged anatomic area and the beam orientation, as (1) hip joint posterior-anterior, (2) hip joint lateral cross-table 45 degrees, (3) lumbar spine anterior-posterior, and (4) lumbar spine lateral 90 degrees. The scattered air kerma rate was measured on a grid surrounding the operating table. For each grid point, the effective dose, eye lens dose, and face skin dose values, normalized over the tube dose area product, were derived. For the effective dose calculations, three radiation protection conditions were considered: (1) with the exposed personnel using no protection measures, (2) with the exposed personnel wearing a 0.5-mm lead-equivalent protective apron, and (3) with the exposed personnel wearing both an apron and a thyroid collar. Maximum permissible workloads for typical hip, spine, and kyphoplasty procedures were derived on the basis of compliance with effective dose, eye lens dose, and skin dose limits. RESULTS We found that the effective dose, eye lens dose, and face skin dose to an orthopaedic surgeon wearing a 0.5-mm lead-equivalent apron will not exceed the corresponding limits if the dose area product of the fluoroscopically guided procedure is <0.38 Gy m (2). When protective eye goggles are also worn, the maximum permissible dose area product increases to 0.70 Gy m (2), while the additional use of a thyroid shield allows a workload of 1.20 Gy m (2). The effective dose to the orthopaedic surgeon working tableside during a typical hip, spine, kyphoplasty procedure was 5.1, 21, and 250 micro Sv, respectively, when a 0.5-mm lead-equivalent apron alone was used. The additional use of a thyroid shield reduced the effective dose to 2.4, 8.4, and 96 micro Sv per typical hip, spine, and kyphoplasty procedure, respectively. CONCLUSIONS The levels of occupational exposure vary considerably with the type of fluoroscopically assisted procedure, staff positioning, and the radiation protection measures used. The data presented in the current study will allow for accurate estimation of the occupational dose to orthopaedic theater personnel.

Sympathetic and sensory neural elements in the tendon of the long head of the biceps.

BACKGROUND Although the tendon of the long head of the biceps is a well-known source of shoulder pain, the pathophysiological basis of this pain has yet to be explained. The aim of this study was to detect and characterize any nervous element of the tendon and to determine a possible explanation for pain originating from this structure. METHODS The nature of the neuronal innervation of the tendon of the long head of the biceps was studied immunohistochemically, in four tendons from different human cadavers, with use of neurofilament antibody 2H3, neurofilament-like antibody 3A10, calcitonin gene-related peptide, substance P, and tyrosine hydroxylase. RESULTS A large neuronal network, asymmetrically distributed along the length of the tendon with a higher degree of innervation at the tendon origin, was identified by the neurofilament and neurofilament-like antibodies 2H3 and 3A10. This innervation was found to be positive for calcitonin gene-related peptide and substance P, suggesting the presence of thinly myelinated or unmyelinated sensory neurons. It was also positive for tyrosine hydroxylase, suggesting a post-ganglionic sympathetic origin. CONCLUSIONS AND CLINICAL RELEVANCE These findings demonstrate that the tendon of the long head of the biceps is innervated by a network of sensory sympathetic fibers, which may play a role in the pathogenesis of shoulder pain.

Hematogenous pyogenic facet joint infection.

Study Design. Retrospective. Objectives. To determine the incidence, clinical presentation, diagnostic laboratory values, imaging characteristics, and optimal treatment of hematogenous pyogenic facet joint infections. Summary of Background Data. There are 27 documented cases of hematogenous pyogenic facet joint infections. Data regarding incidence, clinical presentation, diagnosis, and treatment response are incomplete because of the paucity of reported cases. Methods. This is a retrospective study of all cases of hematogenous pyogenic facet joint infection treated at one institution. Data from previous publications were combined with the present series to identify pertinent clinical characteristics and response to treatment. Results. A total of six cases (4%) of hematogenous pyogenic facet joint infection were identified of 140 cases of hematogenous pyogenic spinal infection at our institution. Combining all reported cases reveals the following: The average patient age is 55 years. Ninety-seven percent of cases occur in the lumbar spine. Epidural abscess formation complicates 25% of the cases of which 38% develop severe neurologic deficit. Erythrocyte sedimentation rate and C-reactive protein are elevated in all cases. Staphylococcus aureus is the most common infecting organism. Magnetic resonance imaging is accurate in identifying the septic joint and associated abscess formation. Percutaneous drainage of the involved joint has a higher rate of success (85%) than treatment with antibiotics alone (71%), but the difference is not significant (P = 0.37). Conclusions. Hematogenous pyogenic facet joint infection is a rare but underdiagnosed clinical entity. Facet joint infections may be complicated by abscess formation in the epidural space or in the paraspinal muscles. Uncomplicated cases treated with percutaneous drainage and antibiotics may fare better than those treated with antibiotics alone. Cases complicated by an epidural abscess and severe neurologic deficit should undergo immediate decompressive laminectomy.

Low-Back Pain in Morbidly Obese Patients and the Effect of Weight Loss Following Surgery

Background: Although low-back pain (LBP) is a common health problem and a source of significant discomfort, disability and work absences, its incidence, severity and outcome have not been extensively investigated in morbidly obese patients undergoing bariatric surgery. Methods: 50 morbidly obese candidates for vertical banded gastroplasty (VBG) were asked to fill in a questionnaire, to assess the incidence and severity of any existing LBP symptoms. 50 non-obese patients, admitted to our surgical unit for management of several benign conditions, were also asked to fill in the same questionnaire and served as controls. 24 months after VBG, the morbidly obese patients were again evaluated for their LBP symptoms. Results: LBP was identified in 29 morbidly obese patients (58%) preoperatively and in only 12 (24%) of the lean controls (P<0.01). 2 years after VBG, with a significant excess weight loss (P<0.0001), only 10 patients continued to have LBP but less frequently and requiring reduced doses of medications compared with the preoperative condition. In the remaining 19 patients with preoperative positive LBP history, the postoperative weight loss was associated with complete resolution of the symptoms. Conclusion: The frequency of LBP is significantly higher in morbidly obese patients than in lean subjects. Surgical weight reduction results in significant improvement and even disappearance of this obesity co-morbidity.

Percutaneous transpedicular discectomy and drainage in pyogenic spondylodiscitis.

The natural history of uncomplicated hematogenous pyogenic spondylodiscitis is self-limiting healing. However, a variable degree of bone destruction frequently occurs, predisposing the spine to painful kyphosis. Delayed treatment may result in serious neurologic complications. Early debridement of these infections by percutaneous transpedicular discectomy can accelerate the natural process of healing and prevent progression to bone destruction and epidural abscess. The purpose of this manuscript is to present our technique of percutaneous transpedicular discectomy (PTD), to revisit this minimally invasive surgical technique with stricter patient selection, and to exclude cases of extensive vertebral body destruction with kyphosis and neurocompression by epidural abscess, infected disc herniation, and foraminal stenosis. In a previously published report of 28 unselected patients with primary hematogenous pyogenic spondylodiscitis, the immediate relief of pain after PTD was 75%, and in the longterm follow-up, the success rate was 68%. Applying stricter patient selection criteria in a second series of six patients (five with primary hematogenous spondylodiscitis and one with secondary postlaminectomydiscectomy spondylodiscitis), all patients with primary hematogenous spondylodiskitis (5/5) experienced immediate relief of pain that remained sustained at 12–18 months follow-up. This procedure was not very effective, however, in the patient who suffered from postlaminectomy infection. This lack of response was attributed to postlaminectomydiscitis instability. The immediate success rate after surgery for unselected patients in this combined series of 34 patients was 76%. This technique can be impressively effective and the results sustained when applied in the early stages of uncomplicated spondylodiscitis and contraindicated in the presence of instability, kyphosis from bone destruction, and neurological deficit. The special point of this procedure is a minimally invasive technique with high diagnostic and therapeutic effectiveness.

External fixation devices in the treatment of fractures of the tibial plafond: A SYSTEMATIC REVIEW OF THE LITERATURE

We have compared the outcomes of the use of external fixation devices for spanning or sparing the ankle joint in the treatment of fractures of the tibial plafond, focusing on the complications and the rates of healing. We have devised a scoring system for the quality of reporting of clinical outcomes, to determine the reliability of the results. We conducted a search of publications in English between 1990 and 2006 using the Pubmed search engine. The key words used were pilon, pylon, plafond fractures, external fixation. A total of 15 articles, which included 465 fractures, were eligible for final evaluation. There were no statistically significant differences between spanning and sparing fixation systems regarding the rates of infection, nonunion, and the time to union. Patients treated with spanning frames had significantly greater incidence of malunion compared with patients treated with sparing frames. In both groups, the outcome reporting score was very low; 60% of reports involving infection, nonunion or malunion scored 0 points.

PAGET’S DISEASE OF THE BONE AND ITS MANAGEMENT

Paget’s disease of bone (PD) is a monostotic or polyostotic non-hormonal osteometabolic disorder. Over a century after the original disease was described by Sir John Paget in 1877, and despite recent intensive studies and widespread interest, its aetiology remains obscure. This review describes the pathomechanism of the structural changes which occur in bone affected with PD, induced by the different dynamic patterns of activity of the disease, and outlines the current methods of treatment.

Studying the association between musculoskeletal disorders, quality of life and mental health. A primary care pilot study in rural Crete, Greece

BackgroundThe burden of musculoskeletal disorders (MSD) on the general health and well-being of the population has been documented in various studies. The objective of this study was to explore the association between MSD and the quality of life and mental health of patients and to discuss issues concerning care seeking patterns in rural Greece.MethodsPatients registered at one rural Primary Care Centre (PCC) in Crete were invited to complete the Nordic Musculoskeletal Questionnaire (NMQ) for the analysis of musculoskeletal symptoms, together with validated instruments for measuring health related quality of life (SF-36) and mental distress (GHQ-28).ResultsThe prevalence rate of MSD was found to be 71.2%, with low back and knee pain being the most common symptoms. Most conditions significantly impaired the quality of life, especially the physical dimensions of SF-36. Depression was strongly correlated to most MSD (p < 0.001). Multiple logistic analyses revealed that patients who consulted the PCC due to MSD were likely to have more mental distress or impaired physical functioning compared to those who did not.ConclusionMusculoskeletal disorders were common in patients attending the rural PCC of this study and were associated with a poor quality of life and mental distress that affected their consultation behaviour.

Chemonucleolysis: the state of the art.

Abstract This review presents the history of chemonucleolysis, the techniques, indications, contraindications, and complications. Presenting an historical overview and comparison of success rates with surgical discectomy may provide a fresh understanding of the controversy surrounding chemonucleolysis and establish its efficacy in relation to more invasive treatments. A review of the literature from 1973 through 1998 for chemonucleolysis, open discectomy, and microdiscectomy provided published success rates for these procedures, and a mean rate with standard deviation was determined. In the experience and opinion of the authors, chemonucleolysis remains a viable alternative for patients who have exhausted all conservative means of treatment. Proper patient selection leads to success rates comparable to open discectomy and microdiscectomy.

Ultrasound velocity through the cortex of phalanges, radius, and tibia in normal and osteoporotic postmenopausal women using a new multisite quantitative ultrasound device.

Damilakis J, Papadokostakis G, Vrahoriti H, et al. Ultrasound velocity through the cortex of phalanges, radius, and tibia in normal and osteoporotic postmenopausal women using a new multisite quantitative ultrasound device. Invest Radiol 2003;38:207–211. Rationale and Objectives.To assess a new multisite quantitative ultrasound (QUS) device (Sunlight Omnisense 7000 S) suitable for the measurement of speed of sound (SOS) in the phalanges, radius, and tibia. Methods.The study group consisted of 270 healthy Caucasian postmenopausal patients (mean age: 60.0 ± 7.6 years) and 53 Caucasian postmenopausal patients (mean age: 67.2 ± 7.4 years) with osteoporotic fractures. Measurements of SOS and bone mineral density (BMD) were carried out in all subjects. Results.Intraobserver in vivo short-term precision was on average 0.76% for the radius, 0.47% for the tibia, and 1.54% for the phalanges. The interobserver precision ranged from 0.77% to 2.39%. Measurements of SOS at the 3 skeletal sites were significantly correlated (r = 0.28–0.44;P < 0.001). Significant correlations were found between SOS at all sites and BMD (r = 0.21–0.41;P < 0.001). The odds ratio for fracture prediction for SOS was 1.47 for tibia, 1.69 for radius, and 2.69 for phalanx. The corresponding odds ratios for BMD at the lumbar spine, femoral neck, and total hip ranged from 2.08 to 3.26. The area under the receiver operating characteristic curve ranged from 0.611 to 0.741 for SOS measurements and from 0.745 to 0.797 for BMD measurements. Conclusions.The Omnisense multisite QUS device exhibits reproducible performance. Among the QUS variables, the phalangeal SOS provides the best discrimination of fracture patients.