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Dive into the research topics where Zinon T. Kokkalis is active.

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Featured researches published by Zinon T. Kokkalis.


Regional Anesthesia and Pain Medicine | 2011

Anatomy and clinical implications of the ultrasound-guided subsartorial saphenous nerve block.

Theodosios Saranteas; George Anagnostis; Tilemachos Paraskeuopoulos; Dimitrios Koulalis; Zinon T. Kokkalis; Mariza Nakou; Sofia Anagnostopoulou; Georgia Kostopanagiotou

Background: We evaluated the anatomic basis and the clinical results of an ultrasound-guided saphenous nerve block close to the level of the nerves exit from the inferior foramina of the adductor canal. Methods: The anatomic study was conducted in 11 knees of formalin-preserved cadavers in which the saphenous nerve was dissected from near its exit from the inferior foramina of the adductor canal. The clinical study was conducted in 23 volunteers. Using a linear probe, the femoral vessels and the sartorius muscle were depicted in short-axis view at the level where the saphenous nerve exits the inferior foramina of the adductor canal. Ten milliliters of 1.5% lidocaine was injected into the compartment structured by the sartorius muscle and the femoral artery. Results: The saphenous nerve was found to exit the adductor canal from its inferior foramina in 9 (81.8%) of 11 and at a more proximal level in 2 (18.2%) of 11 of the anatomic specimens. In a single specimen (9%), the saphenous nerve was formed by the anastomosis of 2 branches. In all the dissections, the saphenous nerve, after exiting the adductor canal, passed between the sartorius muscle and the femoral artery. Of the 23 volunteers, 22 responded with a complete sensory block, whereas a single volunteer demonstrated no sensory blockade. None of the volunteers experienced a motor block of the hip flexors and knee extensors. Conclusions: Ultrasound-guided injection directly caudally from the inferior foramina of the adductor canal, between the sartorius muscle and the femoral artery, seems to be an effective approach for saphenous nerve block.


Orthopedics | 2012

Outcome of a Dynamic Neutralization System for the Spine

George Sapkas; Andreas F. Mavrogenis; Konstantinos A. Starantzis; Konstantinos Soultanis; Zinon T. Kokkalis; Panayiotis J. Papagelopoulos

One hundred fourteen patients (66 men and 48 women; mean age, 49 years) underwent spine stabilization using a dynamic neutralization system between January 1999 and August 2010 for degenerative disk disease, spinal instability, or spinal stenosis. Mean follow-up was 6.8 years (range, 1-11 years). Seven patients were lost to follow-up. Radiological examination and clinical evaluation, including the Oswestry Disability Index, the Roland-Morris Disability Questionnaire, and patient satisfaction, were performed.Mean Oswestry Disability Index score improved from 57% (severe disability) preoperatively to 22% (moderate disability) postoperatively. Mean Roland-Morris Disability Questionnaire score improved from 52% preoperatively to 35% postoperatively; 79 (74%) patients declared themselves very satisfied with the end result of the operation. Postoperatively, 27 (25%) patients experienced complications, including screw loosening (n=22), infection (n=2), back (n=5) and leg (n=2) pain, and endplate vertebral fracture (n=1). Three patients with screw loosening, 2 with deep infection, and 1 with severe persistent back and leg pain underwent rigid spine arthrodesis.Dynamic neutralization systems can be considered for degenerative disk disease, spinal instability, and stenosis. Patient satisfaction with the procedure is excellent. However, in the long term, the complication rate, most commonly screw loosening, is high and reoperations are common. In this setting, long-term follow-up is recommended, and the use of this system should be reconsidered.


Injury-international Journal of The Care of The Injured | 2016

What's new in the management of complex tibial plateau fractures?

Zinon T. Kokkalis; Ilias D. Iliopoulos; Constantinos Pantazis; Elias Panagiotopoulos

The management of complex tibial plateau fractures is ever evolving. The severity of the injury to the surrounding soft tissues influences the timing and the method of fixation. Minimal invasive techniques continue to dominate our philosophy of reduction and reconstruction whereas augmentation of depressed intra-articular fragments remains an accepted strategy to maintain reduction and prevent secondary collapse. Locking plates, conventional plates and fine wire fixators all have been used successfully with satisfactory outcomes. In this article we report on the latest advances made in the management of these complex injuries.


Orthopedics | 2013

Modified McLaughlin technique for neglected locked posterior dislocation of the shoulder.

Zinon T. Kokkalis; Andreas F. Mavrogenis; Efstathios G. Ballas; John Papanastasiou; Panayiotis J. Papagelopoulos

Several surgical techniques have been described for the treatment of posterior shoulder dislocation depending on the time elapsed between injury and surgery and the size of the humeral head impression fracture. When the bone defect is between 25% and 50% of the articular surface of the head, the procedures of choice are autologous bone graft or allograft or subscapularis tendon or lesser tuberosity transfer. In neglected cases in which patients undergo surgery more than 3 weeks after injury, no standard accepted treatment for this injury exists. This article presents a modification of the McLaughlin technique for patients with neglected locked posterior dislocation of the shoulder. Using this technique, the shape of the humeral head was nearly restored with impaction of morselized bone allograft; two suture anchors were inserted into the defect, and the lesser tuberosity with the attached sub-scapularis tendon was transferred into the defect and secured with sutures. Postoperative rehabilitation included immobilization of the shoulder with an external rotation brace for 6 weeks followed by progressive passive, active-assisted, and active range of motion and rotator cuff strengthening exercises for another 6 weeks. This technique resulted in pain-free range of motion, a stable shoulder, and good joint congruency.


Orthopedics | 2012

Bilateral neglected posterior fracture-dislocation of the shoulders.

Zinon T. Kokkalis; Andreas F. Mavrogenis; Efstathios G. Ballas; Panayiotis J. Papagelopoulos; Aristides B. Zoubos

Posterior dislocation of the shoulder is an uncommon injury. Diagnosis is difficult and often missed. Once diagnosed, management must be individualized depending on the amount of the defect of the humeral head and the time from injury. This article presents a case of a 40-year-old man with a 4-month history of bilateral locked posterior fracture-dislocation of the shoulders after a grand mal seizure. Imaging showed loss of the glenohumeral joint lines congruency, reverse Hill-Sachs lesions, and articular defects of 35% and 40% of the humeral heads. A modified McLaughlin technique was performed in both shoulders in a single stage. Through the standard deltopectoral approach, the lesser tuberosity was osteotomized with the subscapularis and capsule attached and elevated to expose the humeral head and glenoid. The shape of the humeral head was restored by packing the defect with morselized bone allograft. Before packing the allograft into the defect, 2 absorbable suture anchors were inserted at the bottom of the defect; the lesser tuberosity was transferred into the defect, and fixed with 2 transosseous horizontal mattress sutures. Stable fixation was evaluated intraoperatively, and the wound was closed in layers. Postoperatively, both shoulders were immobilized with external rotation braces for 6 weeks, followed by passive, active-assisted, and progressively active range of shoulder motion and rotator cuff strengthening exercises for the next 6 weeks. At 12 weeks postoperatively, full range of motion was accomplished, and full activity was allowed. At 22-month follow-up, the patient was satisfied with his level of function; both shoulder joints were painless and stable without apprehension or recurrence of instability. Radiographs showed congruent joints and complete incorporation of the allograft into the defect with restoration of the shape of the humeral head.


BioMed Research International | 2014

Adverse Prognostic Factors and Optimal Intervention Time for Kyphoplasty/Vertebroplasty in Osteoporotic Fractures

Ioannis D. Papanastassiou; Andreas K. Filis; Kamran Aghayev; Zinon T. Kokkalis; Maria A. Gerochristou; Frank D. Vrionis

Introduction. While evidence supports the efficacy of vertebral augmentation (kyphoplasty and vertebroplasty) for the treatment of osteoporotic fractures, randomized trials disputed the value of vertebroplasty. The aim of this analysis is to determine the subset of patients that may not benefit from surgical intervention and find the optimal intervention time. Methods. 27 prospective multiple-arm studies with cohorts of more than 20 patients were included in this meta-analysis. We hereby report the results from the metaregression and subset analysis of those trials reporting on treatment of osteoporotic fractures with kyphoplasty and/or vertebroplasty. Results. Early intervention (first 7 weeks after fracture) yielded more pain relief. However, spontaneous recovery was encountered in hyperacute fractures (less than 2 weeks old). Patients suffering from thoracic fractures or severely deformed vertebrae tended to report inferior results. We also attempted to formulate a treatment algorithm. Conclusion. Intervention in the hyperacute period should not be pursued, while augmentation after 7 weeks yields less consistent results. In cases of thoracic fractures and significant vertebral collapse, surgeons or interventional radiologists may resort earlier to operation and be less conservative, although those parameters need to be addressed in future randomized trials.


European Journal of Orthopaedic Surgery and Traumatology | 2017

Tumors of the hand

Andreas F. Mavrogenis; Georgios N. Panagopoulos; Andrea Angelini; Jan Lesenský; Christos Vottis; Panayiotis D. Megaloikonomos; Zinon T. Kokkalis; Vasilios A. Kontogeorgakos; Pietro Ruggieri; Panayiotis J. Papagelopoulos

Tumors of the hand comprise a vast array of lesions involving skin, soft tissue and bone. The majority of tumors in the hand are benign. Malignant tumors, although rare, do occur and frequently have unique characteristics in this specific anatomic location. Careful staging, histological diagnosis and treatment are essential to optimize clinical outcome. However, straightforward most of the time, hand tumor management does have pitfalls; caution is advised, as a missed or delayed diagnosis or an improperly executed biopsy may have devastating consequences. This article reviews the clinical spectrum of the most common benign and malignant bone and soft tissue tumors of the hand and discusses the clinicopathological findings, imaging features and current concepts in treatment for these tumors.


Case reports in orthopedics | 2016

Sword-Like Trauma to the Shoulder with Open Head-Splitting Fracture of the Head

Andreas Panagopoulos; Konstantinos Pantazis; Ilias D. Iliopoulos; Ioannis Seferlis; Zinon T. Kokkalis

Head-splitting fractures occur as a result of violent compression of the head against the glenoid; the head splits and the tuberosities may remain attached to the fragments or split and separate. Isolated humeral head-splitting fractures are rare injuries. Favorable results with osteosynthesis can be difficult to achieve because of the very proximal location of the head fracture and associated poor vascularity. We present a case of a 67-year-old man who sustained a severe, sword-like trauma to his left shoulder after a road traffic accident with associated isolated open Gustilo-Anderson IIIA humeral head-splitting fracture. Bony union was achieved with minimal internal fixation but the clinical outcome deteriorated due to accompanying axillary nerve apraxia. To our knowledge, this type of sword-like injury with associated humeral head-split fracture has not previously been reported.


Journal of Physical Therapy Science | 2018

The relationship between isokinetic strength and functional performance tests in patients with knee osteoarthritis

Panagiotis Gkrilias; Elias Tsepis; Zinon T. Kokkalis; Elias Panagiotopoulos; Panagiotis Megas

[Purpose] The main purpose of the study was to examine the relationship of a battery of frequently used functional assessment tests with quadriceps and hamstrings isokinetic strength in Knee-osteoarthritis (OA) patients. Secondarily, the predictability of isokinetic strength on these performance variables was also assessed. [Subjects and Methods] Seventeen males and 23 females with Knee-OA, were assessed via a) the common functional tests: 6-minute walk test, Timed up-and-go test, 30-second chair test and 12-stair test and b) isokinetic concentric extension-flexion at 120°/s and 180°/s. [Results] Both Knee Extension and Flexion Peak Torque per Body weight showed moderate to strong, statistically significant correlation, with all 4-functional performance tests, for both velocities. Both 12-stair test and 30-second chair test were significant predictors in all analyses, while the 6-minute walk test was an additional significant predictor of the 120°/s knee flexion. [Conclusion] Thigh muscle strength in both tested velocities proved to be significantly correlated with functional performance. The 12-stair test and 30-second chair test results were significant predictors for isokinetic extension and flexion in both velocities. It appears that those two tests challenge the knee and the surrounding musculature in a manner that reflects muscle strength.


European Journal of Orthopaedic Surgery and Traumatology | 2018

Reduction techniques for difficult subtrochanteric fractures

Zinon T. Kokkalis; Andreas F. Mavrogenis; Dimitris I. Ntourantonis; Vasilios G. Igoumenou; Thekla Antoniadou; Renos Karamanis; Panayiotis D. Megaloikonomos; Georgios N. Panagopoulos; Dimitrios Giannoulis; Eleftheria Souliotis; Theodosis Saranteas; Panayiotis J. Papagelopoulos; Elias Panagiotopoulos

Subtrochanteric fractures can result from high-energy trauma in young patients or from a fall or minor trauma in the elderly. Intramedullary nails are currently the most commonly used implants for the stabilization of these fractures. However, the anesthetic procedure for the patients, the surgical reduction and osteosynthesis for the fractures are challenging. The anesthetic management of orthopedic trauma patients should be based upon various parameters that must be evaluated before the implementation of any anesthetic technique. Surgery- and patient-related characteristics and possible comorbidities must be considered during the pre-anesthetic evaluation. Adequate fracture reduction and proper nail entry point are critical. Understanding of the deforming forces acting on various fracture patterns and knowledge of surgical reduction techniques are essential in obtaining successful outcomes. This article discusses the intraoperative reduction techniques for subtrochanteric fractures in adults and summarizes tips and tricks that the readers may find useful and educative.

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Andreas F. Mavrogenis

National and Kapodistrian University of Athens

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Panayiotis J. Papagelopoulos

National and Kapodistrian University of Athens

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Panayiotis D. Megaloikonomos

National and Kapodistrian University of Athens

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Aristides B. Zoubos

National and Kapodistrian University of Athens

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Georgios N. Panagopoulos

National and Kapodistrian University of Athens

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