Current Progress and Future Perspectives in Contact and Releasing-Type Antimicrobial Coatings of Orthopaedic Implants: A Systematic Review Analysis Emanated from In Vitro and In Vivo Models.

Background: Despite the expanding use of orthopedic devices and the application of strict pre- and postoperative protocols, the elimination of postoperative implant-related infections remains a challenge. Objectives: To identify and assess the in vitro and in vivo properties of antimicrobial-, silver- and iodine-based implants, as well as to present novel approaches to surface modifications of orthopedic implants. Methods: A systematic computer-based review on the development of these implants, on PubMed and Web of Science databases, was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: Overall, 31 in vitro and 40 in vivo entries were evaluated. Regarding the in vitro studies, antimicrobial-based coatings were assessed in 12 entries, silver-based coatings in 10, iodine-based in 1, and novel-applied coating technologies in 8 entries. Regarding the in vivo studies, antimicrobial coatings were evaluated in 23 entries, silver-coated implants in 12, and iodine-coated in 1 entry, respectively. The application of novel coatings was studied in the rest of the cases (4). Antimicrobial efficacy was examined using different bacterial strains, and osseointegration ability and biocompatibility were examined in eukaryotic cells and different animal models, including rats, rabbits, and sheep. Conclusions: Assessment of both in vivo and in vitro studies revealed a wide antimicrobial spectrum of the coated implants, related to reduced bacterial growth, inhibition of biofilm formation, and unaffected or enhanced osseointegration, emphasizing the importance of the application of surface modification techniques as an alternative for the treatment of orthopedic implant infections in the clinical settings.

Bone mineral density, vitamin D and osseous metabolism indices in neurofibromatosis type 1: A systematic review and meta-analysis.

BACKGROUND: Neurofibromatosis type 1 (NF1) is a genetic autosomal neurocutaneous syndrome correlated with skeletal dysplasia and defects in the osseous microarchitecture. The physiological mechanism for the development of NF1-related bone abnormal turnover is still unclear. OBJECTIVES: A meta-analysis was performed to investigate the effects of NF1 on bone mineral density (BMD) and osseous metabolic indices in order to provide clinical evidence for the pathogenesis of the associated skeletal deformities. METHODS: A systematic literature review search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the PubMed/Medline and Web of Science databases from the date of inception of each database through to 10 September 2023. Specific inclusion and exclusion criteria were applied for the identification of studies examining the effects of NF1 on bone strength and metabolism. The Newcastle-Ottawa and Jadad scales were applied to assess the quality of the included studies. RevMan 5.3 software was used for the analysis of the data, and MedCalc was applied to examine publication bias. RESULTS: Overall, 13 studies met the inclusion criteria comprised of 5 cross-sectional, 6 case-control and 2 retrospective studies. 703 patients and 973 healthy subjects formed the NF1 and control group, respectively. The results of the meta-analysis displayed that lumbar (SMD = -3.85, 95%CI = -7.53 to -0.18, Z = 2.05, p = 0.04) and femoral (SMD = -4.78, 95%CI = -8.86 to -0.69, Z = 2.29, p = 0.02) BMD was reduced in the NF1 group. Both in children and adults the serum levels of 25 hydroxyvitamin D3 were also decreased in NF1 group, but without any statistical significance (SMD = -0.62, 95%CI = -1.34 to -0.11, Z = 1.66, p = 0.10). Serum Parathyroid hormone (PTH) (SMD = 0.73, 95%CI = 0.31 to 1.15, Z = 3.43, p = 0.0006) and C-telopeptide of type 1 collagen (CTX) (SMD = 0.82, 95%CI = 0.33 to 1.30, Z = 3.29, p = 0.001) were elevated in NF1 patients, while serum calcium (SMD = -0.10, 95%CI = -0.74 to 0.53, Z = 0.32, p = 0.75) phosphorous (SMD = 0.33, 95%CI = -0.38 to 1.05, Z = 0.92, p = 0.36), alkaline phosphatase (ALP) (SMD = -0.36, 95%CI = -0.77 to 0.05, Z = 1.71, p = 0.09), osteocalcin (SMD = 1.81, 95%CI = -0.37 to -3.98, Z = 1.63, p = 0.10) and bone formation markers (SMD = 0.28, 95%CI = -0.37 to -0.94, Z = 0.85, p = 0.39) were not. CONCLUSION: NF1 is associated with decreased BMD at the lumbar spine and femur. Taking into account that the serum levels of PTH, CTX were increased whereas the concentrations of vitamin D, calcium, phosphorous, ALP, osteocalcin and bone formation markers were not altered significantly in the NF1 patients compared with the healthy subjects, a vitamin D independent dysregulated bone cellular activity could be considered. STUDY REGISTRATION: Registered on PROSPERO (CRD42023424751).

Comparing return to sport activities after short metaphyseal femoral arthroplasty with resurfacing and big femoral head arthroplasties.

OBJECTIVES: Young patients feel that maintaining sport activities after total hip arthroplasty constitutes an important part of their quality of life. The majority of hip surgeons allow patients to return to low-impact activities, but significant caution is advised to taking part in high-impact activities. The purpose of this study is to compare and evaluate the post-operative return to daily living habits and sport activities following short-metaphyseal hip and high functional total hip arthroplasties (resurfacing and big femoral head arthroplasties). MATERIAL AND METHODS: In a study design, 48 patients (55 hips) were enrolled in three different comparative groups, one with the short-metaphyseal arthroplasties, a second with high functional resurfacing arthroplasties and a third of big femoral head arthroplasties. Each patient experienced a clinical examination and evaluated with Harris Hip Score, WOMAC, Sf-36, UCLA activity score, satisfaction VAS, anteroposterior and lateral X-rays of the hip and were followed in an outpatient setting for 2 years. RESULTS: Statistical analysis revealed no notable differences between the three groups regarding their demographic data however significant differences have been found between preoperative and postoperative clinical scores of each group. Also, we fail to reveal any significant differences when comparing data of all three groups at the final 2 years postoperative control regarding their clinical scores. The overall outcome of all three groups was similar, all the patients were satisfied and returned to previous level of sport activities. CONCLUSION: Short metaphyseal hip arthroplasties in young patients intending to return to previous and even high impact sport activities, similar to high functional resurfacing, big femoral head arthroplasties. Short stems with hard on hard bearing surfaces might become an alternative to standard stems and hip resurfacing.

Evaluation of TLICS for thoracolumbar fractures.

PURPOSE: Thoracolumbar Injury Classification and Severity Score (TILCS), facilitates the communication between physicians, and guides to treatment decision with better outcome. A composite injury severity score is calculated from these characteristics stratifying patients into operative and non-operative treatment. Aim of this study is to identify the effectiveness of TLICS scoring for thoracolumbar vertebral fractures without neurological deficits and the efficacy of conservative treatment in patients with TILCS 4. METHODS: 58 patients with thoracolumbar fracture were included. 38 patients with TLICS 1-3 (group A) and 20 patients with TLICS 4 (group B) treated conservatively, were evaluated with traditional two-plain radiographic examination, CT-scan and MRI. The pain and functional scales were used in the clinical evaluation. Local kyphosis angle, sagittal index and height loss percentage were measured in the radiologic evaluation. Mean follow-up period was 28 months. Post-fracture and follow-up values were compared. Functional scores and clinical outcomes of the groups were compared. RESULTS: The mean pain (1 = worse pain, reverse-VAS) and functional scores at the final follow-up were 8.2 and 86 points, respectively (group A), 6.4 and 76 points (group B). The mean period for returning to work was 3.2 (group A) and 3.8 months (group B). Comparing the two groups did not demonstrate any statistical difference of their clinical and functional outcomes. CONCLUSION: The study's results demonstrate that conservative treatment for TLICS 4 thoracolumbar fractures can be safely applied. The conservative treatment of cases scoring TLICS 4 is equally effective to those scoring ≤3.

18-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography scan for monitoring the therapeutic response in experimental Staphylococcus aureus foreign-body osteomyelitis.

BACKGROUND: 18-Fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography ((18)F-FDG PET/CT) scan is useful for diagnosis of osteoarticular infections. Whether (18)F-FDG PET/CT scanning may be used for therapeutic monitoring is not clear. The objective of this study was to develop (18)F-FDG PET/CT scanning for monitoring therapeutic response to antimicrobials in experimental Staphylococcus aureus osteomyelitis. METHODS: A total of 22 rabbits were studied. In 20 animals, the right tibia was inoculated intraoperatively with S. aureus. Two control animals were inoculated with normal saline. A needle was placed in the tibia as a foreign body. Infection was allowed to develop for 21 days when (18)F-FDG PET/CT was performed, the needle was removed, and bone specimens were cultured to confirm infection. Antimicrobial therapy with daptomycin was initiated in all successfully infected animals for 1, 3, or 6 weeks. Following completion of treatment, a second (18)F-FDG PET/CT was performed, animals were euthanized, and infected tibias were harvested for quantitative cultures and histology. A positive scan was defined as (18)F-FDG signal activity greater in the infected tibia than that of the contralateral non-infected control tibia. Therapeutic response was measured by the change of (18)F-FDG signal activity in the infected tibia. RESULTS: All successfully infected animals (n = 14), with microbiologically and/or histologically confirmed osteomyelitis, had positive (18)F-FDG PET/CT scans, while the two control animals had negative scans despite the presence of the foreign body [mean maximum standardized uptake value (SUVmax) (±SD) values 2.96 (±0.80) vs. 1 (±1.10), respectively, P = 0.04]. In the 14 successfully infected animals, the mean SUVmax was significantly higher in the infected compared to the uninfected tibia (P < 0.0001). A SUVmax of 1.4, when used as a cutoff for infection, yielded a diagnostic accuracy of 93 %. At the end of treatment, successfully treated animals and saline controls had a negative (18)F-FDG PET/CT scan (n = 4), while animals with persistent infection despite treatment (n = 12) had a positive (18)F-FDG PET/CT scan (SUVmax 1.0-3.0) (p < 0.001). SUVmax values were significantly reduced after 42 days of treatment from 3.15 ± 0.5 (day 7) to 1.71 ± 0.37 (day 42) (p = 0.05). CONCLUSIONS: (18)F-FDG PET/CT scan is a sensitive and specific tool in therapeutic monitoring of experimental foreign-body osteomyelitis.

Positron emission tomography in spinal infections.

Magnetic resonance imaging is the imaging method of choice for diagnosing infection of the spine in unoperated cases. 2-[(18)F]-fluoro-2deoxy-d-glucose positron emission tomography/computed tomography study is recommended to distinguish between spinal infection and common Modic change in patients with metallic implants and prosthetic replacements and for differentiating tuberculous from pyogenic spondylitis in ambiguous cases, reflecting the activity of the infection. Also, it seems to have a strong clinical impact in more than half of patients with infectious spondylitis, while it is superior to other imaging techniques in revealing residual disease after treatment and early response to therapy. New tracers as well as new hybrid modalities are under investigation.

Isolated Subtalar Distraction Arthrodesis Using Porous Tantalum: A Pilot Study.

BACKGROUND: During reconstructive procedures of the hindfoot, a structural graft is often needed to fill gaps. To eliminate donor site morbidity and limited availability of autografts, porous tantalum was used. METHODS: Eighteen patients who underwent subtalar joint distraction arthrodesis by means of trabecular metal augment were reviewed retrospectively. The results were evaluated clinically, with the American Orthopaedic Foot & Ankle Society (AOFAS) score and the visual analog scale (VAS) for pain, and were assessed radiologically. The mean follow-up period was 18 months. RESULTS: Computed tomography showed sound fusion. There was a marked increase in AOFAS scores and a decrease in VAS scores. Arthrodesis was achieved in all cases with no major postoperative complications. Radiographically, there was a marked increase in all measured parameters (talocalcaneal angle, talocalcaneal height, talar declination angle), and the intraoperatively achieved correction was maintained at the last follow-up visit. CONCLUSION: Our data suggest that porous tantalum may be used as a structural graft option for subtalar arthrodesis. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Reconstruction techniques and clinical results of patellar tendon ruptures: Evidence today.

BACKGROUND: The analysis of the different operative reconstructions of patellar tendon ruptures has not been reported. A critical review of the existing literature was performed to identify the different operative techniques and the post-operative outcomes in acute, chronic and post-total knee arthroplasty (TKA) patellar tendon rupture repairs. METHODS: Using PRISMA guidelines, a review of the English-written literature published after 1947 was performed using the MEDLINE, PubMed and Cochrane libraries in November 2013 to retrieve case series with the keywords "Patellar tendon" AND "Rupture" AND "Repair" in their title or abstract. RESULTS: Forty-one manuscripts, reporting on 503 patients were analysed. Three-hundred-and-fifty-four acute repairs described eight different operative techniques. One-hundred-and-forty-nine chronic repairs described eight different operative techniques. Sixty-eight post-TKA repairs described nine different operative techniques. Six acute, four chronic and seven post-TKA repair operative techniques reported failures. In acute repair, using a primary repair method augmented with cerclage wire, Dall-Miles cable or non-absorbable sutures reported the best clinical results, with a 2% failure rate. Alternatively, for chronic and post-TKA repair, autogeneous grafts were significantly better than primary repair (p=0.0252, 0.0038 respectively). CONCLUSION: Acute surgical repair of a patellar tendon rupture using augmented primary repair is associated with the best post-operative outcomes. In chronic and post-TKA repair, autogeneous grafts produce best post-operative outcomes. Immediate post-operative mobilisation should be considered in all repairs. Future papers reporting on patellar operative repairs should have a standardised scoring method of functional outcome to allow more comprehensive comparison and evaluation.

Salvage of failed hip osteosynthesis for fractures with modular hip prosthesis.

BACKGROUND/PURPOSE: Treating options of failed internal fixation include revision fixation and salvage arthroplasty. The purpose of this study was to evaluate the results, complications and the final functional outcome associated with modular hip arthroplasty. METHODS: Modular arthroplasty was performed in 11 patients due to failed treatment of peritrochanteric fracture. Each patient examination included Trendelenburg test, Harris Hip Score, SF-36, and X-rays of the hip. Examinations were recorded and a paired t test was applied for further statistic analysis. RESULTS: Two years postoperatively, four patients referred no hip pain, seven patients claimed for slight or mild pain, and three patients presented with moderate pain. Statistical analysis revealed a statistically significant difference equally for Harris Hip Score and SF-36. CONCLUSION: The use of modular stems during salvage arthroplasty can decrease the risk of intraoperative and postoperative complications. The final outcome for the patient is satisfactory with functional improvement of the hip.

Strategies for managing bone defects of the lower extremity.

Management of posttraumatic segmental bone loss as a result of severe open injuries of the lower extremity, high-energy closed injuries, and following failed initial treatment of complex fractures that develop pseudarthrosis continues to challenge reconstructive surgeons. There are numerous strategies for dealing with such injuries but the outcome is unpredictable. The procedure is rarely only one stage and complications frequently arise. In most cases the reconstruction process is long and difficult and amputation must be part of the decision-making process. All traditional treatment strategies have advantages and major drawbacks. To overcome some limitations, biologic treatments have been developed based on specific pathways of bone physiology and healing.

Management and outcome of diaphyseal aseptic non-unions of the lower limb: a systematic review.

OBJECTIVES: To review current treatments utilising biological enhancement modalities and their efficacy for the management of lower limb long bone aseptic non-unions. MATERIALS & METHODS: A systematic review of English articles using PubMed Medline; Ovid Medline; Embase; and the Cochrane Library was performed, supplemented by a manual search of bibliographies. RESULTS: Thirteen manuscripts met the inclusion criteria reporting on 428 patients. The overall healing had a pooled estimate of effect size at 94.3%. The calculated summarised estimate of effect size for deep infection rate (413 patients) was 2.3%. Three subgroups were then created on the basis of the exact type of graft used at the non-union site (ABG, BMP-7, BMP-7 + ABG). Comparison between the above subgroups revealed that ABG resulted in approximately 3-fold increase of the odds of healing compared with the use of BMP-7. Combined use of ABGs and BMP-7 improved the odds of healing by 3.5 times compared with BMP-7 alone. However, the previous median operations prior to the implantation of ABG or BMP-7 treatment was 1.09 versus 2.3 respectively (p = 0.02). Although the implantation of ABG was associated with a greater incidence of infection the documented differences did not reach significance. CONCLUSIONS: Although ABG was found to have a higher success rate compared to BMP-7 (95% Vs 87%), patients treated with BMP-7 had a higher number of previous failed interventions, statistically significantly so (BMP-7 is used for the treatment of more recalcitrant non-unions). It is the surgeon's judgement that should determine the most suitable treatment modality, depending on the nature and characteristics (personality) of the non-union and the patient.

PKCε signalling activates ERK1/2, and regulates aggrecan, ADAMTS5, and miR377 gene expression in human nucleus pulposus cells.

The protein kinase C (PKC) signaling, a major regulator of chondrocytic differentiation, has been also implicated in pathological extracellular matrix remodeling, and here we investigate the mechanism of PKCε-dependent regulation of the chondrocytic phenotype in human nucleus pulposus (NP) cells derived from herniated disks. NP cells from each donor were successfully propagated for 25+ culture passages, with remarkable tolerance to repeated freeze-and-thaw cycles throughout long-term culturing. More specifically, after an initial downregulation of COL2A1, a stable chondrocytic phenotype was attested by the levels of mRNA expression for aggrecan, biglycan, fibromodulin, and lumican, while higher expression of SOX-trio and Patched-1 witnessed further differentiation potential. NP cells in culture also exhibited a stable molecular profile of PKC isoforms: throughout patient samples and passages, mRNAs for PKC α, δ, ε, ζ, η, ι, and µ were steadily detected, whereas ß, γ, and θ were not. Focusing on the signalling of PKCε, an isoform that may confer protection against degeneration, we found that activation with the PKCε-specific activator small peptide ψεRACK led sequentially to a prolonged activation of ERK1/2, increased abundance of the early gene products ATF, CREB1, and Fos with concurrent silencing of transcription for Ki67, and increases in mRNA expression for aggrecan. More importantly, ψεRACK induced upregulation of hsa-miR-377 expression, coupled to decreases in ADAMTS5 and cleaved aggrecan. Therefore, PKCε activation in late passage NP cells may represent a molecular basis for aggrecan availability, as part of an PKCε/ERK/CREB/AP-1-dependent transcriptional program that includes upregulation of both chondrogenic genes and microRNAs. Moreover, this pathway should be considered as a target for understanding the molecular mechanism of IVD degeneration and for therapeutic restoration of degenerated disks.

Effect of vertebroplasty on the compressive strength of vertebral bodies.

BACKGROUND CONTEXT: Percutaneous vertebroplasty has been used successfully for many years in the treatment of painful compressive vertebral fractures due to osteoporosis. PURPOSE: To compare the effect of vertebroplasty on the compressive strength of unfractured vertebral bodies. STUDY DESIGN: Biomechanical study on cadaveric thoracic vertebrae. METHODS: Forty vertebral bodies from four cadaveric thoracic spines were used for this experiment. Before testing, each thoracic spine was submitted to bone density testing and radiographic evaluation to rule out any obvious fractures. Under image intensification, 6 mL of a mixture of polymethylmethacrylate (PMMA) with barium (8 g of barium/40 g of PMMA) was injected into every other vertebral body of each spine specimen. After vertebroplasty, all soft tissues were dissected from the spine, and the vertebral bodies were separated and potted for mechanical testing. Testing to failure was performed using a combination of axial compression and anterior flexion moments. Two pneumatic cylinders applied anterior and posterior loads at a distance ratio of 4:3 relative to the anterior vertebral body wall, whereas two additional cylinders applied lateral loads, each at a constant rate of 200 N/s. RESULTS: The average failure loads for nonvertebroplasty specimens was 6724.02 ± 3291.70 N, whereas the specimens injected with PMMA failed at an average compressive force of 5770.50 ± 2133.72 N. No statistically significant difference in failure loads could be detected between intact specimens and those that had undergone vertebroplasty. CONCLUSIONS: Under these specific loading conditions, no significant increase in compressive strength of the vertebral bodies could be documented. This suggests that some caution should be applied to the concept of "prophylactic" vertebroplasty in patients at risk for fracture.

Posterior spinal fusion using pedicle screws.

Few clinical studies have reported polyetheretherketone (PEEK) rod pedicle screw spinal instrumentation systems (CD-Horizon Legacy PEEK rods; Medtronic, Minneapolis, Minnesota). This article describes a clinical series of 52 patients who underwent posterior spinal fusion using the PEEK Rod System between 2007 and 2010. Of the 52 patients, 25 had degenerative disk disease, 10 had lateral recess stenosis, 6 had degenerative spondylolisthesis, 6 had lumbar spine vertebral fracture, 4 had combined lateral recess stenosis and degenerative spondylolisthesis, and 1 had an L5 giant cell tumor. Ten patients had 1-segment fusion, 29 had 2-segment fusion, and 13 had 3-segment fusion. Mean follow-up was 3 years (range, 1.5-4 years); no patient was lost to follow-up. Clinical evaluation was performed using the Oswestry Disability Index and a low back and leg visual analog pain scale. Imaging evaluation of fusion was performed with standard and dynamic radiographs. Complications were recorded. Mean Oswestry Disability Index scores improved from 76% preoperatively (range, 52%-90%) to 48% at 6 weeks postoperatively, and to 34%, 28%, and 30% at 3, 6, and 12 months postoperatively, respectively. Mean low back and leg pain improved from 8 and 9 points preoperatively, respectively, to 6 and 5 points immediately postoperatively, respectively, and to 2 points each thereafter. Imaging union of the arthrodesis was observed in 50 (96%) patients by 1-year follow-up. Two patients sustained screw breakage: 1 had painful loss of sagittal alignment of the lumbar spine and underwent revision spinal surgery with pedicle screws and titanium rods and the other had superficial wound infection and was treated with wound dressing changes and antibiotics for 6 weeks. No adjacent segment degeneration was observed in any patient until the time of this writing.

Congenital variations of the upper cervical spine and their importance in preoperative diagnosis. A case report and a review of the literature.

Several variations of the bony and vascular anatomy around the first and second cervical vertebrae have been reported. Failure to recognise these variations can complicate operations on the upper cervical spine. We present a patient with recent onset of cervical myelopathy due to stenosis at the C3-4 level. Preoperative evaluation identified Klippel-Feil syndrome with cervical fusion of C2-3, aplasia of posterior arch of C1, anomalous vertebral artery course and a "ponticulus posticus" of C2. The combination of these variations in a Klippel-Feil syndrome patient has never been reported. Thus, we recommend a thorough preoperative imaging evaluation, with CT scan and CT angiography or DSA, in addition to plain radiographs. This evaluation is imperative, before a cervical spine surgery, allowing a better understanding of the anatomy, in order to minimise the risks of misplacement of cervical instrumentation especially in such patients.

Fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography scan contributes to the diagnosis and management of brucellar spondylodiskitis.

BACKGROUND: Limited data suggest that fluorine-18 fluoro-2-deoxy-D-glucose (F-18 FDG) positron emission tomography combined with computed tomography (PET/CT) scan may be useful for diagnosing infections of the spine. Brucellar spondylodiskitis might be devastating and current imaging techniques lack sensitivity and specificity. The aim of this prospective study was to determine the role of F-18 FDG PET/CT scan in the diagnosis of brucellar spondylodiskitis and in monitoring the efficacy of its treatment. METHODS: Ten consecutive patients with brucellar spondylitis were prospectively evaluated with PET/CT. Baseline evaluation included also magnetic resonance imaging (MRI) of the affected spine, indices of inflammation, the slide agglutination test (SAT), and the standard hematology and biochemistry. All cases were treated with suitable antibiotics until resolution or significant improvement of clinical and radiological (MRI) findings. Upon completion of treatment, they were re-evaluated with follow-up PET/CT scan. The maximum standardized uptake values (SUV) were measured and compared with SAT. RESULTS: In all patients there was an increased F-18 FDG activity in the infected spine region detected by the initial MRI. F-18 FDG PET/CT provided additional information, compared to MRI, in 4 (40%) patients. More specifically it revealed additional spine lesions (in 3 patients), lymphadenitis, arthritis, organomegaly, as well as new paravertebral soft tissue involvement and epidural masses. This additional information had an impact on the duration of treatment in these patients. At the end of treatment all patients had a complete clinical response; 5 patients had positive serology, 6 patients had residual MRI findings, while 9 had a positive PET/CT but with significantly decreased FDG uptake compared to baseline (median 2.6, range 1.4 - 4.4 vs. median 5.5, range 2.8 - 9.4, p = 0.005). During the follow up period (median 12.5 months) no relapses have been observed. No significant association was observed between the SUV and SAT. CONCLUSIONS: Our study suggests that in patients with brucellar spondylodiskitis F-18 FDG PET/CT scan can provide additional information on the spread of the infection, compared to MRI. Successful treatment is associated with a significant decrease in SUVmax values; thus, PET/CT scan may be a complementary method for determining the efficacy of treatment.

External fixation for displaced 2-part proximal humeral fractures.

Studies have reported conflicting results regarding external fixation for displaced proximal humeral fractures. Compared with open reduction and internal fixation, external fixation for displaced proximal humeral fractures avoids dissection and soft tissue stripping and leads to higher union rates, a lower incidence of avascular necrosis, less scaring of the scapulohumeral interface, and faster rehabilitation. Some authors have reported good or excellent results and minimum complications compared with open reduction and internal fixation; however, others have reported that external fixation does not ensure acceptable reduction and fracture stability, especially in patients with osteoporosis.This article describes 18 patients with displaced 2-part fractures of the surgical neck of the humerus treated with closed reduction and external fixation using the Tension Guide Fixator (Gexfix SA, Carouge, Switzerland) external fixation system between 2010 and 2011. The patients included 14 women and 4 men with a mean age of 39 years. Mean follow-up was 18 months (range, 15-24 months). Fracture union; function using the Constant score, University of California Los Angeles score, Oxford score, and Quick Disabilities of the Arm, Shoulder and Hand shoulder score; and complications were evaluated. All patients experienced fracture union at a mean of 11 weeks (range, 9-13 weeks). The Tension Guide Fixator was removed without anesthesia at the outpatient clinic at a mean of 6 weeks (range, 4-8 weeks) with no loss of reduction or secondary displacement after removal. At 1-year follow-up, mean Constant and University of California Los Angeles scores were excellent, mean Oxford score showed satisfactory joint function, and mean Quick Disabilities of the Arm, Shoulder and Hand score showed minimal pain with no disability.

Can pain influence the severity of findings of an (18)F-FDG PET/CT scan in loosening hip arthroplasty?

Pain is a common symptom after loosening and/or after infection of arthroplasty. The aim of the present case report is to indicate that fluorine-18-fluorodeoxy-glucose positron emission tomography/computerized tomography((18)F-FDG PET/CT) scan can be used for the evaluation of pain at the site of arthroplasty with a semi quantitative measurement. An 84 years old male patient, with a history of papillary thyroid cancer was referred to our Nuclear Medicine Department for an (18)F-FDG PET/CT scan for evaluation of his metastatic disease. He reported right hip prosthesis thirty years ago and now suffered from significant pain in the right hip joint which on a scale from 1 to 10 could be rated as grade 8. White blood cell count, sedimentation rate and C-reactive protein were within normal limits. Four years ago he also had severe pain on the right leg that could be rated as grade 8, and underwent an (18)F-FDG PET/CT scan that showed a maximum standardized uptake value (SUV(max)) of 9.8. A year later, at a follow up (18)F-FDG PET/CT scan and under a similar severe pain, SUV(max) was 10. The patient had a hip prosthesis in the left leg 3 years ago, for which he reported pain that could be rated as grade 3 and the SUV(max) was then 3.7. The degree of (18)F-FDG uptake is related to cellular metabolic rate and to the number of glucose transporters. In inflammation, the activated inflammatory cells demonstrate increased expression of glucose transporters and the affinity of glucose transporters for deoxyglucose is increased by various cytokines and growth factors. Furthermore, when the mononuclear cells and the granulocytes are activated by certain infectious humoral stimuli, they use large amounts of glucose by the hexose monophosphate shunt and the rate of oxygen uptake is intensely increased, during the so called "respiratory burst". In the present case, it was interesting to note that the degree of (18)F-FDG uptake at the sites of loosening hip arthroplasty was related to the severity of pain. Signs of infection or inflammation although not obvious in our case, could not be excluded because sensitivity, specificity and accuracy of PET for detecting infection associated with hip prostheses has been reported to be, 90%, 89.3% and 89.5%, respectively and sensitivity and specificity for detecting periprosthetic inflammation 100% and 45.5%,respectively. In another study using as a criterion for periprosthetic infection the increased (18)F-FDG activity at the bone-prosthesis interface of the femoral component, sensitivity, specificity, positive and negative predictive values for the (18)F-FDG PET study where 85%, 93%, 80% and 95%, respectively. Inflammation, often intense, may be present in aseptic loosening and characterized by increased periprosthetic (18)F-FDG uptake. In conclusion, in our case the degree of (18)F-FDG uptake in a loosening hip arthroplasty was related to the severity of pain although inflammation or infection could also play some role. Further studies are required to prove this suggestion.

Balloon kyphoplasty: scintigraphy as the ultimate decision maker?

Balloon kyphoplasty is still controversial as a treatment for vertebral compression fractures (VCFs) due to osteoporosis. Nevertheless, the authors conducted a prospective study in 60 patients about the effectiveness of scintigraphy, after the conventional roentgenographic examination, as an ultimate decision maker for the identification of the levels to be treated. Seventy-one levels were radiographically and scintigraphically positive, were seen as active, and thus treated. Thirty-seven levels were radiographically negative but positive scintigraphically, were considered as imminent fractures, and thus treated. Ten levels were positive radiographically, but negative scintigraphically, and were not treated as they were considered as healed. The Oswestry Disability Score (100% = worst possible condition) improved from 38.8% +/- 39.5% at baseline, to 2.38% +/- 3.99% on the first postoperative day (p < 0.001), to 2.00% +/- 3.40% at 1 month (p < 0.001) and to 1.93% +/- 3.33% at 6 months (p < 0.001). This preliminary study gives a hint that scintigraphy might work as the ultimate decision maker, even when plain radiographs are negative. Further studies will be needed to compare patients with VCFs positive radiographically and scintigraphically, and other patients with VCFs negative radiographically, but positive scintigraphically.