Konstantinos Malizos - Academia.edu (original) (raw)
Papers by Konstantinos Malizos
Journal of Wrist Surgery, 2015
The scaphocapitate fracture syndrome includes concomitant fractures of the scaphoid and capitate ... more The scaphocapitate fracture syndrome includes concomitant fractures of the scaphoid and capitate with a rotation of 90°or 180°of the proximal fragment of the capitate. Fenton coined the term "naviculo-capitate fracture syndrome" in 1956, and later this term was updated to the modern "scaphocapitate fracture" by Monahan and Galasko. 1,2 Nowadays, most authors believe that the scaphocapitate syndrome is a variety of transscaphoid, transcapitate perilunate fracture-dislocation. 3,4 The mechanism of the syndrome is controversial. Because of the rarity and the complexity of the injury, initial diagnosis may be delayed, and the extent of osseous lesions may be underestimated. Early surgical treatment with open reduction and fracture stabilization is recommended to restore anatomy of the carpus. We report two cases of scaphocapitate fractures of the wrist, diagnosed 3 and 15 days after the injury. Their surgical management, intraoperative findings, and functional outcome after 5.5 and 7 years, respectively, are discussed combined with literature review. The purpose is to highlight the effect of the surgical treatment and anatomic restoration on the long-term outcome of these rare fractures. Case Reports Case 1 A 22-year-old man sustained an injury of his dominant hand after a fall from a height (4-5 m) on an outstretched arm with the wrist in extension. The patient presented to the Keywords ► capitate fracture ► Fenton syndrome ► scaphocapitate fracture syndrome ► scaphoid fracture ► wrist fracturedislocation
The Journal of Bone and Joint Surgery. British volume, 2012
The introduction of a trabecular tantalum rod has been proposed for the management of early-stage... more The introduction of a trabecular tantalum rod has been proposed for the management of early-stage osteonecrosis of the femoral head but serves as a single-point of support of the necrotic lesion. We describe a technique using two or three 4.2 mm (or later 4.7 mm) tantalum pegs for the prevention of collapse of the necrotic lesion. We prospectively studied 21 patients (26 hips) with non-traumatic osteonecrosis of the femoral head treated in this manner. Of these, 21 patients (24 hips) were available for radiological and clinical evaluation at a mean follow-up of 46 months (18 to 67). Radiological assessment showed that only eight hips deteriorated according to the Association Research Circulation Osseous classification, and four hips according to the Classification of the Japanese Investigation Committee of Health and Welfare. Functional improvement was obtained with an improvement in the mean Harris hip score from 65.2 (33.67 to 95) to 88.1 (51.72 to 100), the mean Merle D’Aubigné-P...
2009 9th International Conference on Information Technology and Applications in Biomedicine, 2009
Osteoarthritis and Cartilage, 2015
Introduction: Several studies have shown that osteoarthritis (OA) is strongly associated with met... more Introduction: Several studies have shown that osteoarthritis (OA) is strongly associated with metabolism-related disorders, highlighting OA as the fifth component of the metabolic syndrome (MetS). On the basis of our previous findings on dysregulation of cholesterol homeostasis in OA, we were prompted to investigate whether microRNA-33a (miR-33a), one of the master regulators of cholesterol and fatty acid metabolism, plays a key role in OA pathogenesis. Methods: Articular cartilage samples were obtained from 14 patients with primary OA undergoing total knee replacement surgery. Normal cartilage was obtained from nine individuals undergoing fracture repair surgery. Bioinformatics analysis was used to identify miR-33a target genes. miR-33a and sterol regulatory element-binding protein 2 (SREBP-2) expression levels were investigated using real-time PCR, and their expression was also assessed after treatment with transforming growth factor-β1 (TGF-β1) in cultured chondrocytes. Akt phosphorylation after treatment with both TGF-β1 and miR-33a inhibitor or TGF-β1 and miR-33a mimic was assessed by Western blot analysis. Furthermore, we evaluated the effect of miR-33a mimic and miR-33a inhibitor on Smad7, a negative regulator of TGF-β signaling, on cholesterol efflux-related genes, ATP-binding cassette transporter A1 (ABCA1), apolipoprotein A1 (ApoA1) and liver X receptors (LXRα and LXRβ), as well as on matrix metalloproteinase-13 (MMP-13), using real-time PCR. Results: We found that the expression of miR-33a and its host gene SREBP-2 was significantly elevated in OA chondrocytes compared with normal chondrocytes. Treatment of cultured chondrocytes with TGF-β1 resulted in increased expression of both miR-33a and SREBP-2, as well as in rapid induction of Akt phosphorylation, whereas TGF-β-induced Akt phosphorylation was enhanced by miR-33a and suppressed by inhibition of miR-33a, as a possible consequence of Smad7 regulation by miR-33a. Moreover, treatment of normal chondrocytes with miR-33a resulted in significantly reduced ABCA1 and ApoA1 mRNA expression levels and significantly elevated MMP-13 expression levels, promoting the OA phenotype, whereas miR-33a's suppressive effect was reversed using its inhibitor.
Proceedings of the 10th IEEE International Conference on Information Technology and Applications in Biomedicine, 2010
ABSTRACT This paper discusses a collaborative and innovative e-health system called EMOSNet, for ... more ABSTRACT This paper discusses a collaborative and innovative e-health system called EMOSNet, for the support of medical decision making in the case of amputated or mangled extremities. The goal of the proposed system is to provide communication and collaboration channels between orthopedists located in regional hospitals and special surgeons of the University Hospital of Larissa, in order to confront emergency orthopedic incidences. The main contribution of this work is the development of a suitable framework for the development of a collaborative and innovative e-health system. Using state of the art technology, we develop innovative services, contribute to standardization, interoperability and security issues and provide modeling and simulation techniques for educational purposes. More specifically, we describe a framework of e-health innovation and an overview of the design methodology that relate to e-health service innovation. Our methodology introduces a technological platform for the provision of services for the delivery of a number of e-health services, ranging from second-opinion request and collaboration among distant professionals to the support of medical decision making in the case of amputated or mangled extremities.
SpringerPlus, 2015
Multiple osteonecrotic foci can be clinically silent when located in metaphyses and becomes painf... more Multiple osteonecrotic foci can be clinically silent when located in metaphyses and becomes painful when it affects juxta-articular areas. The purpose of this study was to assess the value of fast MR imaging to depict the underlying pathology in cases with skeletal pain other than the already diagnosed hip osteonecrosis. Between 2008 and 2013, 49 patients with already diagnosed hip osteonecrosis reported symptoms of deep skeletal pain in an anatomical site different from the affected hip joint. All patients after thorough history & clinical examination underwent evaluation with x-rays and a single fat suppressed sequence with MR Imaging applying either T2-w TSE or STIR-TSE at the painful site. False positive and false negative findings were recorded for the conventional x-rays and compared to MRI. Forty four (89.8%) patients were positive for osteonecrotic lesions in this study and 76 symptomatic osteonecrosis lesions were revealed at 14 distinct anatomic sites. The agreement betwee...
Skeletal Radiology, 2010
Purpose To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in ... more Purpose To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in detecting anterior cruciate ligament (ACL), meniscal pathology and traumatic cartilage legions in young patients with chronic deficient anterior cruciate ligament knees. Methods and materials This prospective study included 43 patients (39 male) between the age of 15 and 37 years (mean age 22.6 years) with a history of knee injury sustained at least 3 months prior to the decision to repair a torn ACL. All patients underwent a 3.0 T MR scan with the same standard protocol, including intermediateweighted and three-dimensional spoiled gradient-recalled T1-weighted sequences with fat saturation and subsequently surgical reconstruction of the ACL, along with meniscal and cartilage repair, when necessary. Results All ACL tears were correctly interpreted by 3.0 T MR images. The sensitivity of the MR scans regarding tears of the medial meniscus was 93.7%, the specificity 92.6%, the positive predictive value 88.2% and the negative predictive value 95.8%. The sensitivity of the MR scans regarding tears of lateral meniscus was 85.7%, the specificity was 93.1%, the positive predictive value 85.7% and the negative predictive value 93.1%. With regard to the grading of the cartilage lesions, Cohen's kappa coefficient indicated moderate agreement for grade I and II cartilage lesions (0.5), substantial agreement for grade III and IV cartilage lesions (0.70 and 0.66) and substantial agreement for normal regions (0.75). Regarding location of the cartilage lesions, Cohen's kappa coefficient varied between almost perfect agreement in the lateral femoral condyle and no agreement in the trochlea. Conclusion In the setting of chronic ACL deficiency, MR imaging at 3.0 T achieves satisfactory diagnostic performance regarding meniscal and ligamentous pathology. In the detection of cartilage lesions MRI is less successful.
Knee Surgery, Sports Traumatology, Arthroscopy, 2008
A modified technique for the reconstruction of the extensor mechanism after revision total knee a... more A modified technique for the reconstruction of the extensor mechanism after revision total knee arthroplasty, is described. A medial gastrocnemius flap, in combination with in situ use of semitendinosus tendon autograft through intraosseous patellar tunnel, was used. The patient was followed for 2 years after the final reconstruction. After the procedure, the patient who previously had been dependent on a walker was able to walk without a cane. The above mentioned technique provided good functional outcome in our case.
Knee Surgery, Sports Traumatology, Arthroscopy, 2006
The purpose of this prospective study was to evaluate and compare the results of arthroscopic men... more The purpose of this prospective study was to evaluate and compare the results of arthroscopic meniscal repair using three different techniques. Between January 2002 and March 2004, 57 patients who met the inclusion criteria underwent an arthroscopic meniscal repair. The outside-in technique was used in 17 patients (group A), the inside-out in 20 patients (group B), while the rest of the 20 patients (group C) were managed by the all-inside technique using the Mitek RapidLoc soft tissue anchor (Mitek Surgical Products, Westwood, MA, USA). Anterior cruciate ligament (ACL) reconstruction was performed in 29 patients (51%). The criteria for clinical success included absence of joint line tenderness, locking, swelling, and a negative McMurray test. The minimum follow-up was one year for all groups. The mean follow-up was 23 months for group A, 22 months for group B, and 22 months for group C. All meniscal repairs were considered healed according to our criteria in group A, while 19 out of 20 repairs (95%) healed in group B. Finally 7 of 20 repairs (35%) were considered failures in group C and this difference was statistically significant in comparison with other groups. The time required for meniscal repair averaged 38.5 min for group A, 18.1 min for group B, and 13.6 min for group C. Operation time for meniscal repair in group A was statistically longer in comparison with other groups. There were no significant differences among the three groups concerning complications. According to our results, arhtroscopic meniscal repair with the inside-out technique seems to be superior in comparison with the other methods because it offers a high rate of meniscus healing without prolonged operation time.
Knee Surgery, Sports Traumatology, Arthroscopy, 2013
Journal of Orthopaedic Research, 2009
The aim of our study was to evaluate the in vitro effect of an HMG‐CoA reductase inhibitor, atorv... more The aim of our study was to evaluate the in vitro effect of an HMG‐CoA reductase inhibitor, atorvastatin, on the expression of significant anabolic and catabolic genes in human osteoarthritic chondrocytes and to explore the metabolic pathways involved in this process. Human articular osteoarthritic chondrocytes were cultured in the presence and absence of atorvastatin (10 and 50 µmol/L) for 24 h. Metalloproteinase 13 (MMP‐13), collagen type II (COL2A1), and aggrecan (AGC) mRNA expression levels were evaluated by real‐time PCR, and protein expression levels by Western blot analysis. IL‐1β levels in culture medium was analyzed with ELISA. The effect of the treatment with the mevalonate isoprenoid derivatives farnesol and geranylgeraniol, or the cholesterol precursor squalene, was evaluated in the atorvastatin osteoarthritic chondrocyte cultures. Incubation of osteoarthritic chondrocyte cultures with atorvastatin produced a significant dose‐dependent reduction in IL‐1β production. Ator...
The Journal of Hand Surgery, 2009
The Journal of Bone and Joint Surgery. British volume, 2012
Periosteum is important for bone homoeostasis through the release of bone morphogenetic proteins ... more Periosteum is important for bone homoeostasis through the release of bone morphogenetic proteins (BMPs) and their effect on osteoprogenitor cells. Smoking has an adverse effect on fracture healing and bone regeneration. The aim of this study was to evaluate the effect of smoking on the expression of the BMPs of human periosteum. Real-time polymerase chain reaction was performed for BMP-2,-4,-6,-7 gene expression in periosteal samples obtained from 45 fractured bones (19 smokers, 26 non-smokers) and 60 non-fractured bones (21 smokers, 39 non-smokers). A hierarchical model of BMP gene expression (BMP-2 > BMP-6 > BMP-4 > BMP-7) was demonstrated in all samples. When smokers and non-smokers were compared, a remarkable reduction in the gene expression of BMP-2, -4 and -6 was noticed in smokers. The comparison of fracture and non-fracture groups demonstrated a higher gene expression of BMP-2, -4 and -7 in the non-fracture samples. Within the subgroups (fracture and non-fracture), ...
The Journal of Arthroplasty, 2014
Background: Next-generation sequencing is a well-established technique for sequencing of DNA and ... more Background: Next-generation sequencing is a well-established technique for sequencing of DNA and has recently gained attention in many fields of medicine. Our aim was to evaluate the accuracy of next-generation sequencing in identifying the causative organism(s) in patients with periprosthetic joint infection. Methods: In this prospective study, samples were collected from 65 revision arthroplasties (39 knees and 26 hips) and 17 primary arthroplasties (9 hips and 8 knees). Synovial fluid, deep tissue, and swabs were obtained at the time of the surgical procedure and were shipped to the laboratory for next-generation sequencing. Deep-tissue specimens were also sent to the institutional laboratory for culture. Sensitivity and specificity were calculated for next-generation sequencing, using the Musculoskeletal Infection Society (MSIS) definition of periprosthetic joint infection as the standard. Results: In 28 revisions, the cases were considered to be infected; cultures were positive in 17 cases (60.7% [95% confidence interval (CI), 40.6% to 78.5%]), and next-generation sequencing was positive in 25 cases (89.3% [95% CI, 71.8% to 97.7%]), with concordance between next-generation sequencing and culture in 15 cases. Among the 11 cases of culture-negative periprosthetic joint infection, next-generation sequencing was able to identify an organism in 9 cases (81.8% [95% CI, 48.2% to 97.7%]). Next-generation sequencing identified microbes in 9 (25.0% [95% CI, 12.1% to 42.2%]) of 36 aseptic revisions with negative cultures and in 6 (35.3% [95% CI, 14.2% to 61.7%]) of 17 primary total joint arthroplasties. Next-generation sequencing detected several organisms in most positive samples. However, in the majority of patients who were infected, 1 or 2 organisms were dominant. Conclusions: Next-generation sequencing may be a useful adjunct in identification of the causative organism(s) in culture-negative periprosthetic joint infection. Our findings suggest that some cases of monomicrobial periprosthetic joint infection may have additional organisms that escape detection when culture is used. Further study is required to determine the clinical implications of isolated organisms in samples from patients who are not thought to be infected.
Injury, 2010
A management protocol for ankle and foot osteomyelitis and the outcome in 84 patients treated in ... more A management protocol for ankle and foot osteomyelitis and the outcome in 84 patients treated in a unit with special interest in musculoskeletal infection, is presented. Patients' mean age was 50.7+/-16.5 years and mean follow-up 31.5+/-18.2 months. Systemic antibiotics were administered initially empirically, and later according to cultures. Surgical treatment included surgical debridement and bead-pouch technique, minor amputation (ray or toe), below knee amputation, and joint fusion. "Second-look" procedures were performed after 48-7h. Vascularised grafts or Ilizarov's technique were used for bone defect reconstruction. Soft tissues were managed according the 'reconstructive ladder' concept. Host-type (Cierny's classification) was A in 25, B in 53 and C in 6 patients. Seventy-six infections were chronic. Causes were: open trauma without fracture (45/84), open fractures (9/84), ORIF of closed fractures (25/84) and elective surgery (5/84). Patients underwent 3.0+/-1.5 (range 1-10) operative procedures and spent 14.8+/-12.2 (range 3-60) days in hospital. Two (host-C) patients died. Complications requiring reoperations occurred in 20/84 (2/25 host-A, 16/53 host-B, 2/6 host-C; significant difference between host-A versus host-B and -C patients, p<0.001). Infection recurrence occurred in 12 (none host-A; significant difference between host-A versus host-B and -C patients, p<0.001). Multiple organisms were isolated in 39/84. Ankle arthrodesis using external fixation was performed in 9 (fusion rate 8/9). The free vascularised fibula graft was used in 2 and distraction osteogenesis in 8 patients with a mean bone defect of 5.4 cm (range 3-13). Below knee amputations were performed in 5/84 (3/53 host-B, 2/6 host-C) and foot ray amputations in 8/84 (6/53 host-B, 2/6 host-C). Soft tissue coverage required: free muscle flap transfer in 6/84, reverse soleus flap in 1/84, local fasciocutaneous flaps in 7/84, split thickness skin grafts in 5/84, and vacuum assisted closure in 5/84 patients. Eighty-two surviving patients, including amputees, were able to mobilise independently and were satisfied with the result of treatment. Host-B and -C patients had more complications and infection recurrences and occasionally required amputations. Reconstructive procedures were performed for limb salvage in patients with soft tissue and bone defects and restoration of a functional limb was achieved.
Experimental Biology and Medicine, 2012
Hypertrophy and impaired mineralization are two processes closely associated with osteoarthritis ... more Hypertrophy and impaired mineralization are two processes closely associated with osteoarthritis (OA). 1,25-dihydroxyvitamin D3 (1a,25(OH)2D3) and inorganic phosphate (Pi) are two important factors that are implicated in calcium and phosphate homeostasis of bone metabolism and both can be regulated by the circulating phosphaturic factor fibroblast growth factor 23 (FGF23). The objective of this study was to investigate the role of 1a,25(OH)2D3 and Pi and the molecular mechanism through which they contribute to hypertrophy and mineralization in human osteoarthritic chondrocytes. For this purpose, primary human chondrocytes were obtained from articular cartilage which was collected after total knee replacement surgery in OA patients. FGF23, fibroblast growth factor receptor 1c (FGFR1c), vitamin D3 receptor (VDR), and phosphate inorganic transporter-1 and -2 (PiT-1 and PiT-2) expression levels were evaluated and found to be significantly higher in OA chondrocytes compared with normal. ...
![Research paper thumbnail of Corrigendum to “MR imaging findings in transient osteoporosis of the hip” [Eur. J. Radiol. (2004) 238–244]](https://attachments.academia-assets.com/117411421/thumbnails/1.jpg)
](European Journal of Radiology, 2005
The authors regret that in the original printing of the above article Theophilos Karachalios' nam... more The authors regret that in the original printing of the above article Theophilos Karachalios' name was spelt incorrectly. The correct version is given above.
European Journal of Radiology, 2007
Effective treatment of femoral head osteonecrosis (FHON) requires early diagnosis and accurate as... more Effective treatment of femoral head osteonecrosis (FHON) requires early diagnosis and accurate assessment of the disease severity. The ability to predict in the early stages the risk of collapse is important for selecting a joint salvage procedure. The aim of the present study was to evaluate the outcome in patients treated with vascularized fibular grafts in relation to preoperative MR imaging volumetry. We studied 58 patients (87 hips) with FHON. A semi-automated octant-based lesion measurement method, previously described, was performed on the T1-w MR images. The mean time of postoperative follow-up was 7.8 years. Sixty-three hips were successful and 24 failed and converted to total hip arthroplasty within a period of 2-4 years after the initial operation. The rate of failures for hips of male patients was higher than in female patients. The mean lesion size was 28% of the sphere equivalent of the femoral head, 24 ± 12% for the successful hips and 37 ± 9% for the failed (p < 0.001). The most affected octants were antero-supero-medial (58 ± 26%) and postero-supero-medial (54 ± 31%). All but postero-infero-medial and postero-infero-lateral octants, showed statistically significant differences in the lesion size between patients with successful and failed hips. In conclusion, the volumetric analysis of preoperative MRI provides useful information with regard to a successful outcome in patients treated with vascularized fibular grafts.
European Journal of Radiology, 2013
Objectives: In the present work, we aim to identify changes in the cartilage texture of the injur... more Objectives: In the present work, we aim to identify changes in the cartilage texture of the injured knee in young, physically active, patients by computer analysis of MRI images based on 3.0 T morphological sequences. Methods: Fifty-three young patients with training injury or trauma in one knee underwent MRI and arthroscopy. Textural features were computed from the MRI images of the knee-cartilages and two classes were formed of 28 normal and 16 with pathology only in the medial femoral condyle (MFC) cartilage. Results: Textural features with statistically significant differences between the two classes were found only at the MFC and the medial tibial condyle (MTC) areas. Three features-combinations, at the MFC or the MTC, maximized the between classes separation, thus, rendering alterations in cartilage texture due to injury more evident. The MFC cartilage in the pathology class was found more inhomogeneous in the distribution of gray-levels and of lower texture anisotropy and the opposed MTC cartilage, though normal on MRI and arthroscopy, was found to have lower texture anisotropy than cartilage in the normal class. Conclusion: Texture analysis may be used as an adjunct to morphological MR imaging for improving the detection of subtle cartilage changes and contributes to early therapeutic approach.
Journal of Wrist Surgery, 2015
The scaphocapitate fracture syndrome includes concomitant fractures of the scaphoid and capitate ... more The scaphocapitate fracture syndrome includes concomitant fractures of the scaphoid and capitate with a rotation of 90°or 180°of the proximal fragment of the capitate. Fenton coined the term "naviculo-capitate fracture syndrome" in 1956, and later this term was updated to the modern "scaphocapitate fracture" by Monahan and Galasko. 1,2 Nowadays, most authors believe that the scaphocapitate syndrome is a variety of transscaphoid, transcapitate perilunate fracture-dislocation. 3,4 The mechanism of the syndrome is controversial. Because of the rarity and the complexity of the injury, initial diagnosis may be delayed, and the extent of osseous lesions may be underestimated. Early surgical treatment with open reduction and fracture stabilization is recommended to restore anatomy of the carpus. We report two cases of scaphocapitate fractures of the wrist, diagnosed 3 and 15 days after the injury. Their surgical management, intraoperative findings, and functional outcome after 5.5 and 7 years, respectively, are discussed combined with literature review. The purpose is to highlight the effect of the surgical treatment and anatomic restoration on the long-term outcome of these rare fractures. Case Reports Case 1 A 22-year-old man sustained an injury of his dominant hand after a fall from a height (4-5 m) on an outstretched arm with the wrist in extension. The patient presented to the Keywords ► capitate fracture ► Fenton syndrome ► scaphocapitate fracture syndrome ► scaphoid fracture ► wrist fracturedislocation
The Journal of Bone and Joint Surgery. British volume, 2012
The introduction of a trabecular tantalum rod has been proposed for the management of early-stage... more The introduction of a trabecular tantalum rod has been proposed for the management of early-stage osteonecrosis of the femoral head but serves as a single-point of support of the necrotic lesion. We describe a technique using two or three 4.2 mm (or later 4.7 mm) tantalum pegs for the prevention of collapse of the necrotic lesion. We prospectively studied 21 patients (26 hips) with non-traumatic osteonecrosis of the femoral head treated in this manner. Of these, 21 patients (24 hips) were available for radiological and clinical evaluation at a mean follow-up of 46 months (18 to 67). Radiological assessment showed that only eight hips deteriorated according to the Association Research Circulation Osseous classification, and four hips according to the Classification of the Japanese Investigation Committee of Health and Welfare. Functional improvement was obtained with an improvement in the mean Harris hip score from 65.2 (33.67 to 95) to 88.1 (51.72 to 100), the mean Merle D’Aubigné-P...
2009 9th International Conference on Information Technology and Applications in Biomedicine, 2009
Osteoarthritis and Cartilage, 2015
Introduction: Several studies have shown that osteoarthritis (OA) is strongly associated with met... more Introduction: Several studies have shown that osteoarthritis (OA) is strongly associated with metabolism-related disorders, highlighting OA as the fifth component of the metabolic syndrome (MetS). On the basis of our previous findings on dysregulation of cholesterol homeostasis in OA, we were prompted to investigate whether microRNA-33a (miR-33a), one of the master regulators of cholesterol and fatty acid metabolism, plays a key role in OA pathogenesis. Methods: Articular cartilage samples were obtained from 14 patients with primary OA undergoing total knee replacement surgery. Normal cartilage was obtained from nine individuals undergoing fracture repair surgery. Bioinformatics analysis was used to identify miR-33a target genes. miR-33a and sterol regulatory element-binding protein 2 (SREBP-2) expression levels were investigated using real-time PCR, and their expression was also assessed after treatment with transforming growth factor-β1 (TGF-β1) in cultured chondrocytes. Akt phosphorylation after treatment with both TGF-β1 and miR-33a inhibitor or TGF-β1 and miR-33a mimic was assessed by Western blot analysis. Furthermore, we evaluated the effect of miR-33a mimic and miR-33a inhibitor on Smad7, a negative regulator of TGF-β signaling, on cholesterol efflux-related genes, ATP-binding cassette transporter A1 (ABCA1), apolipoprotein A1 (ApoA1) and liver X receptors (LXRα and LXRβ), as well as on matrix metalloproteinase-13 (MMP-13), using real-time PCR. Results: We found that the expression of miR-33a and its host gene SREBP-2 was significantly elevated in OA chondrocytes compared with normal chondrocytes. Treatment of cultured chondrocytes with TGF-β1 resulted in increased expression of both miR-33a and SREBP-2, as well as in rapid induction of Akt phosphorylation, whereas TGF-β-induced Akt phosphorylation was enhanced by miR-33a and suppressed by inhibition of miR-33a, as a possible consequence of Smad7 regulation by miR-33a. Moreover, treatment of normal chondrocytes with miR-33a resulted in significantly reduced ABCA1 and ApoA1 mRNA expression levels and significantly elevated MMP-13 expression levels, promoting the OA phenotype, whereas miR-33a's suppressive effect was reversed using its inhibitor.
Proceedings of the 10th IEEE International Conference on Information Technology and Applications in Biomedicine, 2010
ABSTRACT This paper discusses a collaborative and innovative e-health system called EMOSNet, for ... more ABSTRACT This paper discusses a collaborative and innovative e-health system called EMOSNet, for the support of medical decision making in the case of amputated or mangled extremities. The goal of the proposed system is to provide communication and collaboration channels between orthopedists located in regional hospitals and special surgeons of the University Hospital of Larissa, in order to confront emergency orthopedic incidences. The main contribution of this work is the development of a suitable framework for the development of a collaborative and innovative e-health system. Using state of the art technology, we develop innovative services, contribute to standardization, interoperability and security issues and provide modeling and simulation techniques for educational purposes. More specifically, we describe a framework of e-health innovation and an overview of the design methodology that relate to e-health service innovation. Our methodology introduces a technological platform for the provision of services for the delivery of a number of e-health services, ranging from second-opinion request and collaboration among distant professionals to the support of medical decision making in the case of amputated or mangled extremities.
SpringerPlus, 2015
Multiple osteonecrotic foci can be clinically silent when located in metaphyses and becomes painf... more Multiple osteonecrotic foci can be clinically silent when located in metaphyses and becomes painful when it affects juxta-articular areas. The purpose of this study was to assess the value of fast MR imaging to depict the underlying pathology in cases with skeletal pain other than the already diagnosed hip osteonecrosis. Between 2008 and 2013, 49 patients with already diagnosed hip osteonecrosis reported symptoms of deep skeletal pain in an anatomical site different from the affected hip joint. All patients after thorough history & clinical examination underwent evaluation with x-rays and a single fat suppressed sequence with MR Imaging applying either T2-w TSE or STIR-TSE at the painful site. False positive and false negative findings were recorded for the conventional x-rays and compared to MRI. Forty four (89.8%) patients were positive for osteonecrotic lesions in this study and 76 symptomatic osteonecrosis lesions were revealed at 14 distinct anatomic sites. The agreement betwee...
Skeletal Radiology, 2010
Purpose To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in ... more Purpose To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in detecting anterior cruciate ligament (ACL), meniscal pathology and traumatic cartilage legions in young patients with chronic deficient anterior cruciate ligament knees. Methods and materials This prospective study included 43 patients (39 male) between the age of 15 and 37 years (mean age 22.6 years) with a history of knee injury sustained at least 3 months prior to the decision to repair a torn ACL. All patients underwent a 3.0 T MR scan with the same standard protocol, including intermediateweighted and three-dimensional spoiled gradient-recalled T1-weighted sequences with fat saturation and subsequently surgical reconstruction of the ACL, along with meniscal and cartilage repair, when necessary. Results All ACL tears were correctly interpreted by 3.0 T MR images. The sensitivity of the MR scans regarding tears of the medial meniscus was 93.7%, the specificity 92.6%, the positive predictive value 88.2% and the negative predictive value 95.8%. The sensitivity of the MR scans regarding tears of lateral meniscus was 85.7%, the specificity was 93.1%, the positive predictive value 85.7% and the negative predictive value 93.1%. With regard to the grading of the cartilage lesions, Cohen's kappa coefficient indicated moderate agreement for grade I and II cartilage lesions (0.5), substantial agreement for grade III and IV cartilage lesions (0.70 and 0.66) and substantial agreement for normal regions (0.75). Regarding location of the cartilage lesions, Cohen's kappa coefficient varied between almost perfect agreement in the lateral femoral condyle and no agreement in the trochlea. Conclusion In the setting of chronic ACL deficiency, MR imaging at 3.0 T achieves satisfactory diagnostic performance regarding meniscal and ligamentous pathology. In the detection of cartilage lesions MRI is less successful.
Knee Surgery, Sports Traumatology, Arthroscopy, 2008
A modified technique for the reconstruction of the extensor mechanism after revision total knee a... more A modified technique for the reconstruction of the extensor mechanism after revision total knee arthroplasty, is described. A medial gastrocnemius flap, in combination with in situ use of semitendinosus tendon autograft through intraosseous patellar tunnel, was used. The patient was followed for 2 years after the final reconstruction. After the procedure, the patient who previously had been dependent on a walker was able to walk without a cane. The above mentioned technique provided good functional outcome in our case.
Knee Surgery, Sports Traumatology, Arthroscopy, 2006
The purpose of this prospective study was to evaluate and compare the results of arthroscopic men... more The purpose of this prospective study was to evaluate and compare the results of arthroscopic meniscal repair using three different techniques. Between January 2002 and March 2004, 57 patients who met the inclusion criteria underwent an arthroscopic meniscal repair. The outside-in technique was used in 17 patients (group A), the inside-out in 20 patients (group B), while the rest of the 20 patients (group C) were managed by the all-inside technique using the Mitek RapidLoc soft tissue anchor (Mitek Surgical Products, Westwood, MA, USA). Anterior cruciate ligament (ACL) reconstruction was performed in 29 patients (51%). The criteria for clinical success included absence of joint line tenderness, locking, swelling, and a negative McMurray test. The minimum follow-up was one year for all groups. The mean follow-up was 23 months for group A, 22 months for group B, and 22 months for group C. All meniscal repairs were considered healed according to our criteria in group A, while 19 out of 20 repairs (95%) healed in group B. Finally 7 of 20 repairs (35%) were considered failures in group C and this difference was statistically significant in comparison with other groups. The time required for meniscal repair averaged 38.5 min for group A, 18.1 min for group B, and 13.6 min for group C. Operation time for meniscal repair in group A was statistically longer in comparison with other groups. There were no significant differences among the three groups concerning complications. According to our results, arhtroscopic meniscal repair with the inside-out technique seems to be superior in comparison with the other methods because it offers a high rate of meniscus healing without prolonged operation time.
Knee Surgery, Sports Traumatology, Arthroscopy, 2013
Journal of Orthopaedic Research, 2009
The aim of our study was to evaluate the in vitro effect of an HMG‐CoA reductase inhibitor, atorv... more The aim of our study was to evaluate the in vitro effect of an HMG‐CoA reductase inhibitor, atorvastatin, on the expression of significant anabolic and catabolic genes in human osteoarthritic chondrocytes and to explore the metabolic pathways involved in this process. Human articular osteoarthritic chondrocytes were cultured in the presence and absence of atorvastatin (10 and 50 µmol/L) for 24 h. Metalloproteinase 13 (MMP‐13), collagen type II (COL2A1), and aggrecan (AGC) mRNA expression levels were evaluated by real‐time PCR, and protein expression levels by Western blot analysis. IL‐1β levels in culture medium was analyzed with ELISA. The effect of the treatment with the mevalonate isoprenoid derivatives farnesol and geranylgeraniol, or the cholesterol precursor squalene, was evaluated in the atorvastatin osteoarthritic chondrocyte cultures. Incubation of osteoarthritic chondrocyte cultures with atorvastatin produced a significant dose‐dependent reduction in IL‐1β production. Ator...
The Journal of Hand Surgery, 2009
The Journal of Bone and Joint Surgery. British volume, 2012
Periosteum is important for bone homoeostasis through the release of bone morphogenetic proteins ... more Periosteum is important for bone homoeostasis through the release of bone morphogenetic proteins (BMPs) and their effect on osteoprogenitor cells. Smoking has an adverse effect on fracture healing and bone regeneration. The aim of this study was to evaluate the effect of smoking on the expression of the BMPs of human periosteum. Real-time polymerase chain reaction was performed for BMP-2,-4,-6,-7 gene expression in periosteal samples obtained from 45 fractured bones (19 smokers, 26 non-smokers) and 60 non-fractured bones (21 smokers, 39 non-smokers). A hierarchical model of BMP gene expression (BMP-2 > BMP-6 > BMP-4 > BMP-7) was demonstrated in all samples. When smokers and non-smokers were compared, a remarkable reduction in the gene expression of BMP-2, -4 and -6 was noticed in smokers. The comparison of fracture and non-fracture groups demonstrated a higher gene expression of BMP-2, -4 and -7 in the non-fracture samples. Within the subgroups (fracture and non-fracture), ...
The Journal of Arthroplasty, 2014
Background: Next-generation sequencing is a well-established technique for sequencing of DNA and ... more Background: Next-generation sequencing is a well-established technique for sequencing of DNA and has recently gained attention in many fields of medicine. Our aim was to evaluate the accuracy of next-generation sequencing in identifying the causative organism(s) in patients with periprosthetic joint infection. Methods: In this prospective study, samples were collected from 65 revision arthroplasties (39 knees and 26 hips) and 17 primary arthroplasties (9 hips and 8 knees). Synovial fluid, deep tissue, and swabs were obtained at the time of the surgical procedure and were shipped to the laboratory for next-generation sequencing. Deep-tissue specimens were also sent to the institutional laboratory for culture. Sensitivity and specificity were calculated for next-generation sequencing, using the Musculoskeletal Infection Society (MSIS) definition of periprosthetic joint infection as the standard. Results: In 28 revisions, the cases were considered to be infected; cultures were positive in 17 cases (60.7% [95% confidence interval (CI), 40.6% to 78.5%]), and next-generation sequencing was positive in 25 cases (89.3% [95% CI, 71.8% to 97.7%]), with concordance between next-generation sequencing and culture in 15 cases. Among the 11 cases of culture-negative periprosthetic joint infection, next-generation sequencing was able to identify an organism in 9 cases (81.8% [95% CI, 48.2% to 97.7%]). Next-generation sequencing identified microbes in 9 (25.0% [95% CI, 12.1% to 42.2%]) of 36 aseptic revisions with negative cultures and in 6 (35.3% [95% CI, 14.2% to 61.7%]) of 17 primary total joint arthroplasties. Next-generation sequencing detected several organisms in most positive samples. However, in the majority of patients who were infected, 1 or 2 organisms were dominant. Conclusions: Next-generation sequencing may be a useful adjunct in identification of the causative organism(s) in culture-negative periprosthetic joint infection. Our findings suggest that some cases of monomicrobial periprosthetic joint infection may have additional organisms that escape detection when culture is used. Further study is required to determine the clinical implications of isolated organisms in samples from patients who are not thought to be infected.
Injury, 2010
A management protocol for ankle and foot osteomyelitis and the outcome in 84 patients treated in ... more A management protocol for ankle and foot osteomyelitis and the outcome in 84 patients treated in a unit with special interest in musculoskeletal infection, is presented. Patients&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; mean age was 50.7+/-16.5 years and mean follow-up 31.5+/-18.2 months. Systemic antibiotics were administered initially empirically, and later according to cultures. Surgical treatment included surgical debridement and bead-pouch technique, minor amputation (ray or toe), below knee amputation, and joint fusion. &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;Second-look&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; procedures were performed after 48-7h. Vascularised grafts or Ilizarov&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s technique were used for bone defect reconstruction. Soft tissues were managed according the &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;reconstructive ladder&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; concept. Host-type (Cierny&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s classification) was A in 25, B in 53 and C in 6 patients. Seventy-six infections were chronic. Causes were: open trauma without fracture (45/84), open fractures (9/84), ORIF of closed fractures (25/84) and elective surgery (5/84). Patients underwent 3.0+/-1.5 (range 1-10) operative procedures and spent 14.8+/-12.2 (range 3-60) days in hospital. Two (host-C) patients died. Complications requiring reoperations occurred in 20/84 (2/25 host-A, 16/53 host-B, 2/6 host-C; significant difference between host-A versus host-B and -C patients, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Infection recurrence occurred in 12 (none host-A; significant difference between host-A versus host-B and -C patients, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Multiple organisms were isolated in 39/84. Ankle arthrodesis using external fixation was performed in 9 (fusion rate 8/9). The free vascularised fibula graft was used in 2 and distraction osteogenesis in 8 patients with a mean bone defect of 5.4 cm (range 3-13). Below knee amputations were performed in 5/84 (3/53 host-B, 2/6 host-C) and foot ray amputations in 8/84 (6/53 host-B, 2/6 host-C). Soft tissue coverage required: free muscle flap transfer in 6/84, reverse soleus flap in 1/84, local fasciocutaneous flaps in 7/84, split thickness skin grafts in 5/84, and vacuum assisted closure in 5/84 patients. Eighty-two surviving patients, including amputees, were able to mobilise independently and were satisfied with the result of treatment. Host-B and -C patients had more complications and infection recurrences and occasionally required amputations. Reconstructive procedures were performed for limb salvage in patients with soft tissue and bone defects and restoration of a functional limb was achieved.
Experimental Biology and Medicine, 2012
Hypertrophy and impaired mineralization are two processes closely associated with osteoarthritis ... more Hypertrophy and impaired mineralization are two processes closely associated with osteoarthritis (OA). 1,25-dihydroxyvitamin D3 (1a,25(OH)2D3) and inorganic phosphate (Pi) are two important factors that are implicated in calcium and phosphate homeostasis of bone metabolism and both can be regulated by the circulating phosphaturic factor fibroblast growth factor 23 (FGF23). The objective of this study was to investigate the role of 1a,25(OH)2D3 and Pi and the molecular mechanism through which they contribute to hypertrophy and mineralization in human osteoarthritic chondrocytes. For this purpose, primary human chondrocytes were obtained from articular cartilage which was collected after total knee replacement surgery in OA patients. FGF23, fibroblast growth factor receptor 1c (FGFR1c), vitamin D3 receptor (VDR), and phosphate inorganic transporter-1 and -2 (PiT-1 and PiT-2) expression levels were evaluated and found to be significantly higher in OA chondrocytes compared with normal. ...
European Journal of Radiology, 2005
The authors regret that in the original printing of the above article Theophilos Karachalios' nam... more The authors regret that in the original printing of the above article Theophilos Karachalios' name was spelt incorrectly. The correct version is given above.
European Journal of Radiology, 2007
Effective treatment of femoral head osteonecrosis (FHON) requires early diagnosis and accurate as... more Effective treatment of femoral head osteonecrosis (FHON) requires early diagnosis and accurate assessment of the disease severity. The ability to predict in the early stages the risk of collapse is important for selecting a joint salvage procedure. The aim of the present study was to evaluate the outcome in patients treated with vascularized fibular grafts in relation to preoperative MR imaging volumetry. We studied 58 patients (87 hips) with FHON. A semi-automated octant-based lesion measurement method, previously described, was performed on the T1-w MR images. The mean time of postoperative follow-up was 7.8 years. Sixty-three hips were successful and 24 failed and converted to total hip arthroplasty within a period of 2-4 years after the initial operation. The rate of failures for hips of male patients was higher than in female patients. The mean lesion size was 28% of the sphere equivalent of the femoral head, 24 ± 12% for the successful hips and 37 ± 9% for the failed (p < 0.001). The most affected octants were antero-supero-medial (58 ± 26%) and postero-supero-medial (54 ± 31%). All but postero-infero-medial and postero-infero-lateral octants, showed statistically significant differences in the lesion size between patients with successful and failed hips. In conclusion, the volumetric analysis of preoperative MRI provides useful information with regard to a successful outcome in patients treated with vascularized fibular grafts.
European Journal of Radiology, 2013
Objectives: In the present work, we aim to identify changes in the cartilage texture of the injur... more Objectives: In the present work, we aim to identify changes in the cartilage texture of the injured knee in young, physically active, patients by computer analysis of MRI images based on 3.0 T morphological sequences. Methods: Fifty-three young patients with training injury or trauma in one knee underwent MRI and arthroscopy. Textural features were computed from the MRI images of the knee-cartilages and two classes were formed of 28 normal and 16 with pathology only in the medial femoral condyle (MFC) cartilage. Results: Textural features with statistically significant differences between the two classes were found only at the MFC and the medial tibial condyle (MTC) areas. Three features-combinations, at the MFC or the MTC, maximized the between classes separation, thus, rendering alterations in cartilage texture due to injury more evident. The MFC cartilage in the pathology class was found more inhomogeneous in the distribution of gray-levels and of lower texture anisotropy and the opposed MTC cartilage, though normal on MRI and arthroscopy, was found to have lower texture anisotropy than cartilage in the normal class. Conclusion: Texture analysis may be used as an adjunct to morphological MR imaging for improving the detection of subtle cartilage changes and contributes to early therapeutic approach.