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Dive into the research topics where John Vlamis is active.

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Featured researches published by John Vlamis.


Injury-international Journal of The Care of The Injured | 2003

Long-term outcome of patients with avascular necrosis, after internal fixation of femoral neck fractures

K.E Nikolopoulos; S.A Papadakis; K.T Kateros; G.S Themistocleous; John Vlamis; Panayiotis J. Papagelopoulos; Panayiotis A Nikiforidis

We retrospectively reviewed 84 patients who underwent internal fixation of an intracapsular femoral neck fracture. The mean age was 58 years and the time from injury to operative treatment was 5.3 days. The mean follow-up was 4.7 years (range, 2-8 years). At the latest follow-up, in the 46 patients with undisplaced (Garden I, II) fractures, nonunion occurred in two patients and avascular necrosis of the femoral head in nine. Six of these nine patients had a good or excellent result, one had a fair result, and two had a poor result. Of 35 patients with no sign of avascular necrosis, 32 patients had a good or excellent result, two a fair and one had a poor result. In the group of 38 patients with displaced (Garden III, IV) fractures, nonunion occurred in six patients and avascular necrosis of the femoral head in 15. Of these 15 patients, 10 had a good or excellent result, two had a fair result, and three had a poor result. Of 17 patients with no sign of avascular necrosis, 14 had an excellent result and three patients a poor result. Overall only five of the 24 patients who developed avascular necrosis of the femoral head had undergone total hip arthroplasty. Internal fixation remains a simple and safe, method of treatment for both undisplaced and displaced femoral neck fractures in middle-age patients. Despite the relatively high rate of avascular necrosis after internal fixation of femoral neck fractures, only a few of these patients (20%) required further surgical treatment in the follow-up period of this study.


Spine | 2001

Halo pin intracranial penetration and epidural abscess in a patient with a previous cranioplasty: case report and review of the literature.

Panayiotis J. Papagelopoulos; George Sapkas; Konstantinos Kateros; Stamatios A. Papadakis; John Vlamis; Matthew E. Falagas

Study Design. Report of a patient with an epidural abscess after halo pin intracranial penetration at the site of a previous cranioplasty. Objectives. To report a rare case of intracranial penetration at the site of a previous cranioplasty associated with epidural abscess, and to discuss the diagnostic and therapeutic approach to its management. Summary of Background Data. The most serious complications associated with use of halo device occur when pins penetrate the inner table of the skull, resulting in cerebrospinal fluid leak and rarely in an intracranial abscess. However, no mention of intracranial halo pin penetration at the site of a previous cranioplasty was found in the literature. Methods. A 64-year-old man with ankylosing spondylitis had a halo vest placed for management of a fracture dislocation through the C5–C6 intervertebral disc space associated with left C6 radiculopathy. One week later, the patient experienced fever and headache associated with pain, redness, and drainage at the site of the insertion of the left posterior pin. Computed tomography of the brain showed a 1.5-cm intracranial penetration of the halo pin through a previous cranioplasty of the temporal bone, associated with epidural abscess and cerebral edema in the left temporoparietal lobe. The pins and the halo vest were removed, the pin site was cleaned, and a Philadelphia cervical collar was applied. Staphylococcus epidermidis grew on the culture of drainage from the pin site. The patient started immediate intravenous antibiotic treatment for 2 weeks, followed by oral antibiotics for 2 additional weeks. Results. The patient had gradual improvement of his symptoms within the first 48 hours. At the latest follow-up visit, he had fully recovered and his fracture had healed. Conclusions. The halo device should not be used for patients with a previous cranioplasty, especially if the pins cannot be inserted at other safe areas of the skull. A thorough medical history and physical examination of the skull are important before the application of a halo device. Computed tomography of the skull may be necessary before elective halo application for patients with concomitant head trauma, confusion, or intoxication and for patients with a previous cranioplasty to ascertain the safest pin sites.


Orthopedics | 2001

Treatment of lumbosacral radicular pain with epidural steroid injections.

Panayiotis J. Papagelopoulos; Haralambos G Petrou; Pantelis G Triantafyllidis; John Vlamis; Maria Psomas-Pasalis; Demetrios S. Korres; Konstantinos Stamos

Fifty patients with an average age of 47 years received epidural steroid injections for lumbosacral radicular pain due to disk herniation or spinal stenosis. All patients had failed previous conservative treatment. Mean follow-up was 24 months (range: 12-36 months). Immediately after injection, all 50 patients reported various degrees of relief from leg and back pain. At the last follow-up examination, 68% of patients were asymptomatic, 20% had no change in preinjection radicular symptoms, and 12% had various degrees of relief. No significant correlation was found between pain relief, age, or number of injections. Early pain relief may be anticipated after epidural steroid injections in 80% of patients with radicular symptoms due to disk herniation or spinal stenosis.


Injury-international Journal of The Care of The Injured | 2013

Radiation-free distal locking of intramedullary nails: Evaluation of a new electromagnetic computer-assisted guidance system

Ioannis P. Stathopoulos; Panagiotis K. Karampinas; Dimitrios-Stergios Evangelopoulos; Kalliopi Lampropoulou-Adamidou; John Vlamis

Distal locking of intramedullary nails (IMNs) is a difficult part of intramedullary nailing (IMN) that could be time-consuming and expose the surgeon, the surgery personnel and the patient to a considerable amount of radiation as fluoroscopy is usually guiding the procedure. Utilization of electromagnetic fields for that purpose offers an attractive alternative. The SURESHOT™ Distal Targeting System (Smith & Nephew, Inc., Memphis, TN, USA) is a novel commercially available radiation-free aiming system that utilizes computerized electromagnetic field tracking technology for the distal locking of IMNs. In order to evaluate the efficacy of the system we conducted the present study. Nineteen patients (six females-thirteen males, mean age 39.5 years, range 17-85 years) with closed diaphyseal fracture of the femur (eight patients) or the tibia (eleven patients) were treated with IMN using the SURESHOT™ Distal Targeting System for the distal interlocking. All targeting attempts were successful at first try and followed by correct positioning of the screws. Mean time for distal locking of tibial IMNs (two screws) was 219sec (range 200-250sec). Mean time for distal locking of femoral IMNs (two screws) was 249 (range 220-330sec). In the current study the SURESHOT™ Distal Targeting System proved to be accurate, fast and easy to learn.


Orthopedics | 2016

Complications After Hip Nailing for Fractures.

Andreas F. Mavrogenis; Georgios N. Panagopoulos; Panayiotis D. Megaloikonomos; Vasilios G. Igoumenou; Ioannis P. Galanopoulos; Christos Vottis; Panayiotis Karabinas; Panayiotis Koulouvaris; Vasilios Kontogeorgakos; John Vlamis; Panayiotis J. Papagelopoulos

Pertrochanteric fractures in elderly patients represent a major health issue. The available surgical options are fixation with extramedullary devices, intramedullary nailing, and arthroplasty. Intramedullary nailing for hip fractures has become more popular in recent years. Advantages of intramedullary nailing for hip fracture fixation include a more efficient load transfer due to the proximity of the implant to the medial calcar, less implant strain and shorter lever arm because of its closer positioning to the mechanical axis of the femur, significantly less soft tissue disruption and periosteal stripping of the femoral cortex, shorter operative time and hospital stay, fewer blood transfusions, better postoperative walking ability, and lower rates of leg-length discrepancy. Compromise of the posteromedial cortex and/or the lateral cortex, a subtrochanteric extension of the fracture, and a reversed obliquity fracture pattern represent signs of fracture instability, warranting the use of intramedullary nailing. However, the use of intramedullary nailing, with its unique set of clinical implications, has introduced a new set of complications. The reported complications include malalignment, cutout, infection, false drilling, wrong lag screw length and drill bit breakage during the interlocking procedure, external or internal malrotation (≥20°) of the femoral diaphysis, elongation of the femur (2 cm), impaired bone healing, periprosthetic fracture distal to the tip of the nail, fracture collapse, implant failure, lag screw intrapelvic migration, neurovascular injury, secondary varus deviation, complications after implant removal, trochanteric pain, and refracture. Many of these complications are related to technical mistakes. This article reviews intramedullary nailing for the treatment of pertrochanteric femoral fractures, with an emphasis on complications.


Journal of Orthopaedic Research | 2014

Chondroprotective effect of high‐dose zoledronic acid: An experimental study in a rabbit model of osteoarthritis

Kalliopi Lampropoulou-Adamidou; Ismene Dontas; Ioannis P. Stathopoulos; Lubna Khaldi; Pavlos Lelovas; John Vlamis; Ioannis K. Triantafillopoulos; Nikolaos Papaioannou

To address the need to impact the subchondral bone‐articular cartilage interaction for the treatment of degenerative osteoarthritis (OA), bisphosphonates may be used as a means to inhibit the subchondral bone resorption. The purpose of the present study is to evaluate the chondroprotective effect of zoledronic acid (ZOL) in a model of OA. Eighteen adult male rabbits underwent an anterior cruciate ligament transection and were separated into two groups: ZOL group (n = 10) received 0.6 mg/kg intravenous injection of ZOL on day 1, 15, and 29 and placebo group (n = 8) received saline. The animals were euthanized at 8 weeks. Macroscopically, the ZOL group had significantly milder ulcerations, cartilage softening and fibrillation compared to the placebo group. Microscopically, morphology of the articular cartilage was better in the ZOL treated group compared with the placebo group, without complete disorganization in any section of the ZOL group. Furthermore, the chondrocytes in the ZOL treated group were mainly cloning, indicating cartilage repairing and regeneration process, while in the placebo group hypocellularity predominated. Additionally, subchondral necrosis was evident in some specimens of the placebo group. Zoledronic acid, in a high‐dose regimen, proved to be chondroprotective in a well‐established animal model of OA.


Journal of Bone and Joint Surgery-british Volume | 2013

Charnley low-friction arthroplasty in patients 35 years of age or younger: Results at a minimum of 23 years

Kalliopi Lampropoulou-Adamidou; G. Georgiades; John Vlamis; George Hartofilakidis

We evaluated the outcome of 41 consecutive Charnley low-friction arthroplasties (LFAs) performed by a single surgeon in 28 patients aged ≤ 35 years at operation between 23 and 36 years previously. There were 20 women and eight men with a mean age of 32 years (23 to 35) at surgery. Two patients (three hips) were lost to follow-up at 12 and 17 years post-operatively, respectively, and one patient (one hip) died at 13 years post-operatively. These patients were excluded from the final evaluation. The survival rate of the acetabular components was 92.7% (95% confidence interval (CI) 88.7 to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1% (95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8) at 25 years. The results indicate that the Charnley LFA remains a reasonable choice in the treatment of young patients and can serve for comparison with newer techniques and implants.We evaluated the outcome of 41 consecutive Charnley low-friction arthroplasties (LFAs) performed by a single surgeon in 28 patients aged ≤ 35 years at operation between 23 and 36 years previously. There were 20 women and eight men with a mean age of 32 years (23 to 35) at surgery. Two patients (three hips) were lost to follow-up at 12 and 17 years post-operatively, respectively, and one patient (one hip) died at 13 years post-operatively. These patients were excluded from the final evaluation. The survival rate of the acetabular components was 92.7% (95% confidence interval (CI) 88.7 to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1% (95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8) at 25 years. The results indicate that the Charnley LFA remains a reasonable choice in the treatment of young patients and can serve for comparison with newer techniques and implants. Cite this article: Bone Joint J 2013;95-B:1052–6.


Clinical Orthopaedics and Related Research | 2013

Results of Total Hip Arthroplasty Differ in Subtypes of High Dislocation

George Hartofilakidis; George C. Babis; Kalliopi Lampropoulou-Adamidou; John Vlamis

BackgroundIn a previous study, we described two subtypes of high dislocation of the hip depending on the presence (C1) or absence (C2) of a false acetabulum, yet we have already presented the concise followup of total hip arthroplasty (THA) in these patients as a group at a minimum of 15 years.Questions/purposesIn this retrospective study, we investigated differences in the results of THA in the C1 and C2 subtypes of high dislocation such as (1) survivorship of the reconstructions; (2) Merle d’Aubigné-Postel clinical scores; (3) leg lengthening and femoral shortening; and (4) site of reattachment and union rate of the greater trochanter.MethodsWe included 49 hips of the C1 subtype and 30 hips of the C2 subtype operated on from 1976 to 1994. We evaluated survivorship (using reoperation for any reason as the end point) and performed chart and radiographic reviews.ResultsThe 15-year survival was 84% (± 10% [95% CI]) for the C1 subtype and 60% (± 17% [95% CI]) for the C2 subtype (p = 0.001). Cox regression analysis, after adjustment for confounding factors, showed also statistically significantly worse survivorship in the C2 subtype (p = 0.021) and, after adjustment for possible predictive factors, found a statistically significant relationship of high dislocation subtype (p = 0.018) and trochanteric union (p = 0.005) with survival of THAs. Pain, function, and mobility scores improved from preoperative to last followup in C1 and C2 groups but they did not differ between C1 and C2 hips. C2 hips were lengthened more (p < 0.001) despite greater amounts of femoral shortening (p = 0.006). Site of reattachment and the risk of greater trochanter nonunion were not different between the groups.ConclusionsWe found important differences in fundamental parameters after THA in the high-dislocation subtypes, including the risk of revision, which was higher in patients whose hips did not have a false acetabulum. These findings indicate that while reporting THA results in patients with high dislocation, mixing results of the two subtypes may lead to statistical bias.Level of EvidenceLevel III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.


Diabetic Foot & Ankle | 2012

Conservative treatment of an anterior-lateral ankle dislocation without an associated fracture in a diabetic patient: a case report

Panagiotis K. Karampinas; Ioannis P. Stathopoulos; John Vlamis; Vasilios D. Polyzois; Spyros G. Pneumatikos

Anterior or anterior-lateral dislocation of the ankle is a rare condition that can be treated conservatively as well as any other similar types of ankle dislocations without associated fractures. We present a case report of an anterior-lateral ankle dislocation with a concomitant avulsion injury of the ankles anterior capsule in a diabetic patient that was treated conservatively. At the patients visit 12 months after the initial injury, he was asymptomatic with full range of motion of the ankle joint. To our knowledge, we could not identify this type of an injury in a diabetic patient that was treated successfully with conservative treatment in the existing literature.


Foot & Ankle International | 2015

Isolated Subtalar Distraction Arthrodesis Using Porous Tantalum A Pilot Study

Eustratios A. Papadelis; Panagiotis K. Karampinas; Eustratios Kavroudakis; John Vlamis; Vasilios D. Polizois; Spiros G. Pneumaticos

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.

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Panagiotis K. Karampinas

National and Kapodistrian University of Athens

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Spiros G. Pneumaticos

National and Kapodistrian University of Athens

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Kalliopi Lampropoulou-Adamidou

National and Kapodistrian University of Athens

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Panayiotis J. Papagelopoulos

National and Kapodistrian University of Athens

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Eustratios A. Papadelis

National and Kapodistrian University of Athens

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George Hartofilakidis

National and Kapodistrian University of Athens

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Ioannis P. Stathopoulos

National and Kapodistrian University of Athens

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Vasilios D. Polyzois

National and Kapodistrian University of Athens

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Andreas F. Mavrogenis

National and Kapodistrian University of Athens

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Demetrios S. Korres

National and Kapodistrian University of Athens

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