Andreas Panagopoulos

Prof. Andreas Panagopoulos

orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 September 2007 in International Journal of Sports Medicine
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Journal Article
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APAndreas Panagopoulos
Andreas Panagopoulos
LNL. van Niekerk
L. van Niekerk
ITI. K. Triantafillopoulos
I. K. Triantafillopoulos
Recurrent dislocation, subluxation and functional instability due to patellofemoral pain might be present in 30 % to 60 % of patients managed non-operatively for posttraumatic patella instability. Disruption of the capsule, medial patella retinaculum and/or vastus medialis obliquus have been associated with recurrent patella instability but recently the medial patellofemoral ligament (MPFL) has been recognised as the most important ligamentous stabiliser preventing lateral dislocation of the patella. Many nonanatomical surgical techniques for the treatment of recurrent patellar dislocation have been described in the literature. These procedures alter the pre-morbid patella mechanics by several principles, including the release of tight lateral ligaments, tensioning of loose medial structures and distal realignment of the extensor mechanism or a combination of these. Very few address the principle site of pathology in patella dislocation, i.e., the torn MPFL. The outcomes are inconsistent and many studies have reported recurrent dislocations and patellofemoral pain and arthritis in up to 40 %. We describe a simple technique of MPFL reconstruction using a single hamstring tendon graft which is passed through the medial intermuscular septum at the adductor's magnus insertion and is fixed to the superomedial pole of the patella. A comprehensive review of the existing techniques of MPFL reconstruction using semitendinosus tendon autografts is also provided.

25 June 2018 in Journal of Medical Case Reports
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APAndreas Panagopoulos
Andreas Panagopoulos
ITIrini TATANI
Irini TATANI
HKHelen (Eleni) Kourea
Helen (Eleni) Kourea
ZKZ. T. Kokkalis
Z. T. Kokkalis
KPK. Panagopoulos
K. Panagopoulos
PMPanagiotis Megas
Panagiotis Megas
Brown tumors represent a rare clinical manifestation reported in approximately 3% of patients with primary hyperparathyroidism and correspond to radiologically osteolytic lesions with well-defined borders in different parts of the skeleton. We report the case of a 53-year-old white man who presented to our hospital with osteolytic lesions of his distal ulna and radius, causing pain and swelling of 2-month duration. A subsequent biopsy revealed histological features consistent with giant cell tumor and a complete resection of his distal ulna was followed, along with curettage and cementoplasty of the distal radial metaphysis. Two weeks later, he was re-admitted with diffuse musculoskeletal soreness, anorexia, constipation, nausea, and localized abdominal pain and multiple osteolytic lesions on plain radiographs. A histopathological examination of the ulna and radius specimens showed similar findings and, given the multifocality, brown tumors related to primary or secondary hyperparathyroidism was included in the differential diagnosis. A laboratory examination showed high total serum calcium (14.5 mg/dl) and low serum phosphorus and 25-hydroxyvitamin D levels. Primary hyperparathyroidism was suspected and confirmed by the elevated parathyroid hormone levels of 1453 pg/mL. At radiological work-up, using computed tomography, ultrasonography, and parathyroid subtraction technetium-99m sestamibi scintigraphy, a 4.5 × 2.5 × 3.2 cm mass emanating from the right lobe of his thyroid gland was detected, displaying extensive uptake in the right lower parathyroid gland. After appropriate medical support including hyperhydration and high doses of diuretics and diphosphonates, his laboratory profile normalized and he underwent total thyroidectomy with removal of the parathyroid glands. Our patient is now recovering 12 months after surgery, with normal values of serum parathyroid hormone and calcium levels. The lytic bone lesions have almost disappeared and no other additional orthopedic intervention was necessary. The present case report emphasizes the need of inclusion of brown tumors in the differential diagnosis of multifocal osteolytic bone lesions, in order to avoid harmful surgical interventions. Laboratory testing of serum phosphate, calcium levels, and parathyroid hormone levels should always be included in the routine survey of patients with multifocal osteolytic lesions.

15 September 2014 in The Open Orthopaedics Journal
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Journal Article
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CMCharalampos Matzaroglou
Charalampos Matzaroglou
CGChristos S Georgiou
Christos S Georgiou
APAndreas Panagopoulos
Andreas Panagopoulos
KAKostantinos Assimakopoulos
Kostantinos Assimakopoulos
HWHans-Joachim Wilke
Hans-Joachim Wilke
KKKonstantinos Kafchitsas
Konstantinos Kafchitsas
The three major causes of vertebral body collapse include infection, malignant neoplasia, and trauma and it may be difficult to distinguish between them, particularly in the presence of severe osteoporosis. In 1891, however, Dr Hermann Kümmell, further added another possibility of vertebral body crush; the delayed posttraumatic collapse. As originally described, this rare clinical entity includes patients, who after a trivial trauma and an asymptomatic clinical course they develop a progressive vertebral body collapse and a painful kyphosis. Although more than a century has passed from its initial description, only few cases have been reported in the literature, whereas the main pathologic eliciting event is still under investigation. As a consequence, great controversy exists regarding the discrete features of the clinical course, its radiographic appearance and the histopathological findings. To explain the time lag between the initial trauma and the occurrence of the vertebral collapse, the hypothesis of ischemic necrosis was advanced. Equation of Kümmell’s disease with vertebral osteonecrosis, however, has wrongly led many authors to report cases of Kümmell’s disease, even in the absence of history of spinal trauma. On the other hand, high coincidence of vertebral osteonecrosis and the pathognomonic radiographic finding of intravertebral vacuum cleft, has further added to the confusion. In this review we present an overview of the literature on Kümmell’s disease, focusing on the different proposed eliciting mechanisms. We also highlight controversial subjects on clinical course, diagnosis and treatment of this entity, in an attempt to further clarify patients’ inclusion criteria.

1 January 2012 in Orthopedics
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Journal Article
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APAndreas Panagopoulos
Andreas Panagopoulos
LNLouw van Niekerk
Louw van Niekerk
ITIoannis Triantafillopoulos
Ioannis Triantafillopoulos
Few studies have assessed the results of autologous chondrocyte implantation in patients with high-impact activities. The purpose of this study was to evaluate the early functional outcome and activity level after 2-stage autologous chondrocyte implantation in professional soldiers and athletes. Nineteen patients with an average age of 32.2 years were treated with autologous chondrocyte implantation and followed up for a minimum of 2 years. All patients except 2 had received previous arthroscopic treatment with debridement and/or microfracture. The mean size of the postdebridement defect was 6.54 cm 2 . Using Novocart technology (B. Braun-Tetec, Reutlingen, Germany), periosteal patch and matrix-assisted autologous chondrocyte implantation was sequentially performed with no randomization. The average subjective knee evaluation score and Lysholm score improved from 39.16 and 42.42, respectively, preoperatively to 62.4 and 69.4, respectively, at latest follow-up. Median Tegner activity score was 8.8 before injury, 3.8 preoperatively, and 6.15 at latest follow-up. Second-look arthroscopy was performed in 11 patients due to persistent pain, decreased range of movement, and mechanical symptoms. Six of 19 (31.5%) patients with professional or recreational athletic activities returned to preinjury levels of athletic performance. This study shows that mid-term results with autologous chondrocyte implantation in high-performance patients are not as good as have been reported with other similar technologies. Motivational issues during prolonged rehabilitation, multiple surgical interventions before autologous chondrocyte implantation, patient age, and large defects can potentially influence the outcome and overall performance in this selected group of patients.

1 March 2009 in Journal of Bone and Joint Surgery
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PDPanayiotis Dimakopoulos
Panayiotis Dimakopoulos
APAndreas Panagopoulos
Andreas Panagopoulos
GKGeorgios Kasimatis
Georgios Kasimatis
BACKGROUND: The optimal treatment of displaced fractures of the proximal part of the humerus remains controversial. We evaluated the long-term functional and radiographic results of transosseous suture fixation in a series of selected displaced fractures of the proximal part of the humerus. METHODS: Over an eleven-year period, a consecutive series of 188 patients with a specifically defined displaced fracture of the proximal part of the humerus underwent open reduction and internal fixation with transosseous sutures. Twenty patients were lost to follow-up and three died before the time of follow-up, leaving a cohort of 165 patients (ninety-four women and seventy-one men; mean age, fifty-four years) available for the study. Forty-five (27%) of the injuries were four-part fractures with valgus impaction; sixty-four (39%) were three-part fractures; and fifty-six (34%) were two-part fractures of the greater tuberosity, thirty-six (64%) of which were associated with anterior dislocation of the shoulder. All fractures were fixed with transosseous, nonabsorbable, number-5 Ethibond sutures. Associated rotator cuff tears detected in fifty-seven patients (35%) were also repaired. Over a mean follow-up period of 5.4 years, functional outcome was assessed with the Constant score. Follow-up radiographs were assessed for fracture consolidation, malunion, nonunion, heterotopic ossification, and signs of impingement, humeral head osteonecrosis, and degenerative osteoarthritis. RESULTS: All fractures, except for two three-part fractures of the greater tuberosity, united within four months. The quality of fracture reduction as seen on the first postoperative radiograph was regarded as excellent/very good in 155 patients (94%), good in seven (4%), and poor in three (2%). Malunion was present in nine patients (5%) at the time of the last follow-up; six of the nine had had good or poor initial reduction and three, excellent/very good reduction. Humeral head osteonecrosis was seen in eleven (7%) of the 165 patients; four demonstrated total and seven, partial collapse. Fifteen patients had heterotopic ossification, but none had functional impairment. Four patients had signs of impingement syndrome, and two had arthritis. At the time of the final evaluation, the mean Constant score was 91 points, and the mean Constant score as a percentage of the score for the unaffected shoulder, unadjusted for age and gender, was 94%. CONCLUSIONS: The clinical and radiographic results of this transosseous suture technique were found to be satisfactory at an average of 5.4 years postoperatively. Advantages of this technique include less surgical soft-tissue dissection, a low rate of humeral head osteonecrosis, fixation sufficient to allow early passive joint motion, and the avoidance of bulky and expensive implants. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

7 April 2022 in Journal of Orthopaedic Surgery and Research
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Journal Article
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APAndreas Panagopoulos
Andreas Panagopoulos
KSKonstantina Solou
Konstantina Solou
ITIrini TATANI
Irini TATANI
ITIoannis K. Triantafyllopoulos
Ioannis K. Triantafyllopoulos
JLJohn Lakoumentas
John Lakoumentas
ZKZinon Kokkalis
Zinon Kokkalis
Background: The purpose of the present study was to systematically review the current treatment strategies for the treatment of Neer type IIB distal clavicle fractures in terms of functional outcome and complication rates and to examine the most appropriate surgical method by comparing all the available surgical techniques and implants. Methods: We performed a systematic review of the existing literature (2000–2021) in accordance with the PRISMA statement. We searched PubMed, Scopus, Web of Science, Research Gate and Google Scholar using the general terms ‘distal AND clavicle AND fracture’ to capture as many reports as possible. The MINORS tool was used to assess the risk of bias of the nonrandomized studies. We categorized the reported surgical techniques into four main types: open or arthroscopic coracoclavicular (CC) stabilization, locking plate fixation with or without CC augmentation, hook plate fixation and acromioclavicular joint (ACJ) transfixation. We reported findings for two main outcomes: clinical results and complication rates categorized into major and minor. Results: Our database search yielded a total of 630 records; 34 studies were appropriate for qualitative analysis. There were 790 patients, with a mean age of 40.1 years, a female percentage of 37% and a mean follow-up period of 29.3 months. In total, 132 patients received a hook plate, 252 received a locking plate, 368 received CC stabilization and 41 received transacromial transfixation. All studies were retrospective and had fair MINORS scores. Locking plate, CC stabilization and ACJ transfixation showed similar clinical results but were much better than hook plate fixation; CC augmentation did not significantly improve the outcome of locking plate fixation. The rate of major complications was similar among groups; hook plate and AC joint transfixation had the worst rates of minor complications. Open CC techniques were slightly better than arthroscopic techniques. Conclusions: The present systematic review for the optimal fixation method for Neer type IIB fractures of the distal clavicle showed similar major complication rates among techniques; the hook plate technique demonstrated inferior clinical results to other techniques. Open CC stabilization and locking plate fixation without CC augmentation seem to be the best available treatment options.