Publications by Year: 2011

2011
Lykoudi I, Kottis G, Nikolaou VS, Setaki P, Fassoulaki A, Efstathopoulos N. Intra-articular morphine enhances analgesic efficacy of ropivacaine for knee arthroscopy in ambulatory patients. Orthopedics. 2011;34(2):91.Abstract
The aim of this double-blind, randomized control trial was to compare the effectiveness of intra-articular ropivacaine alone or with morphine or ketoprofen for controlling pain after arthroscopic knee surgery. One hundred fifty-six patients scheduled for elective knee arthroscopy were recruited. All patients received general anesthesia and were randomly assigned to 4 groups to receive intra-articular ropivacaine 40 mg (group R), ropivacaine 24 mg plus morphine 8 mg (group R+M), ropivacaine 36 mg plus ketoprofen 100 mg (group R+K), or normal saline (group N/S). Pain, sedation, orientation, nausea, vomiting, and urine retention were recorded at 0, 1, 2, 4, 8, 12, and 24 hours postoperatively. Pain was evaluated by a 10-cm visual analog scale (VAS). When the pain was >2, a suppository of 400 mg paracetamol plus 10 mg codeine plus 50 mg caffeine was given. Results showed that at 4 hours postoperatively, pain differed significantly among the 4 groups (P<.001), with less pain recorded in the R+M group. Similarly, the number of suppositories administered postoperatively to the R+M group was significantly less (P<.001) vs the other groups. Patients who received ropivacaine and morphine or normal saline had a higher incidence of nausea and vomiting vs the other groups (P=.001 and P=.036, respectively). The combination of intra-articular ropivacaine and morphine is associated with less pain after knee arthroscopy during early recovery but with a higher incidence of nausea and vomiting. However, the addition of ketoprofen to ropivacaine provides relatively satisfactory pain relief, but with fewer side effects compared to morphine.
Nikolaou VS, Tan HB, Haidukewych G, Kanakaris N, Giannoudis PV. Proximal tibial fractures: early experience using polyaxial locking-plate technology. Int Orthop. 2011;35(8):1215-21.Abstract
Between 2004 and 2009, 60 patients with proximal tibial fractures were included in this prospective study. All fractures were treated with the polyaxial locked-plate fixation system (DePuy, Warsaw, IN, USA). Clinical and radiographic data, including fracture pattern, changes in alignment, local and systemic complications, hardware failure and fracture union were analysed. The mean follow-up was 14 (12-36) months. According to the Orthopaedic Trauma Association (OTA) classification, there were five 41-A, 28 41-B and 27 41-C fractures. Fractures were treated percutaneously in 30% of cases. Double-plating was used in 11 cases. All but three fractures progressed to union at a mean of 3.2 (2.5-5) months. There was no evidence of varus collapse as a result of polyaxial screw failure. No plate fractured, and no screw cut out was noted. There was one case of lateral joint collapse (>10°) in a patient with open bicondylar plateau fracture. The mean Knee Society Score at the time of final follow-up was 91 points, and the mean functional score was 89 points. The polyaxial locking-plate system provided stable fixation of extra-articular and intra-articular proximal tibial fractures and good functional outcomes with a low complication rate.
Nikolaou VS, Desy NM, Bergeron SG, Antoniou J. Total knee replacement and chemical thromboprophylaxis: current evidence. Curr Vasc Pharmacol. 2011;9(1):33-41.Abstract
Thromboembolic disease remains one of the most devastating and potentially lethal complications after elective total knee replacement (TKR) surgery. Studies have shown that 40-85% of patients undergoing TKR will develop venographically confirmed deep vein thrombosis (DVT) if they are not given any type of post-operative thromboprophylaxis and approximately 0.1 to 1.7% will suffer fatal pulmonary embolism (PE). Consequently, there is a general consensus that patients undergoing elective TKR require adequate antithrombotic prophylaxis. The following article reviews current evidence regarding chemical thromboprophylaxis after total knee replacement. Clinical guidelines as described by the American Academy of Orthopaedic Surgeons (AAOS), the American College of Chest Physicians (ACCP) and the UK's National Institute for Health and Clinical Excellence (NICE) are summarized along with the differences between the recommendations. The results of the new oral anticoagulants are reviewed as well as the most recent developments in the search for the most effective venous thromboembolism (VTE) prophylaxis after TKR surgery.
Nikolaou VS, Harwood PJ, Karadimas EJ, Tan HB, Giannoudis PV. Novel anticoagulants: new evidence for emerging drugs and their potential application in major lower limb surgery. Curr Vasc Pharmacol. 2011;9(1):54-60.Abstract
For decades, parenteral drugs, such as the low molecular weight heparins and unfractionated heparins or vitamin K antagonists, have been used as anticoagulants for prevention of venous thromboembolism following major lower limb surgery. However, these regiments have limitations that rendered the quest for new anticoagulants mandatory. Recently, research has been focused on the development of orally active small molecules that directly target thrombin or activated factor X (FXa). These regiments exhibit a number of characteristics that an "ideal" anticoagulant should possess. Currently, two agents, dabigatran etexilate and rivaroxaban, which inhibit thrombin and FXa, respectively have been approved in the European Union and Canada for venous thromboprophylaxis in patients undergoing elective hip- or knee-replacement surgery. Other agents are at an early or late stage of clinical evaluation. In this study, we summarize the current evidence for these new developed or under development drugs regarding their applications in the filed of lower limb orthopaedic surgery.
Brin YS, Nikolaou VS, Joseph L, Zukor DJ, Antoniou J. Imageless computer assisted versus conventional total knee replacement. A Bayesian meta-analysis of 23 comparative studies. Int Orthop. 2011;35(3):331-9.Abstract
We have undertaken a meta-analysis of the English literature, to assess the component alignment outcomes after imageless computer assisted (CAOS) total knee arthroplasty (TKA) versus conventional TKA. We reviewed 23 publications that met the inclusion criteria. Results were summarised via a Bayesian hierarchical random effects meta-analysis model. Separate analyses were conducted for prospective randomised trials alone, as well as for all randomised and observational studies. In 20 papers (4,199 TKAs) we found a reduction in outliers rate of approximately 80% in limb mechanical axis when operated with the CAOS. For the coronal femoral and tibial implants positions, the analysis included 3,058 TKAs. The analysis for the femoral implant showed a reduction in outliers rate of approximately 87% and for the tibial implant a reduction in outliers rate of approximately 80%. Imageless navigation when performing TKA improves component orientation and postoperative limb alignment. The clinical significance of these findings though has to be proven in the future.
Mavrogenis AF, Nikolaou V, Efstathopoulos N, Korres DS, Pneumaticos SG. Functional outcome and complications using the intramedullary hip screw for intertrochanteric fractures. J Surg Orthop Adv. 2011;20(3):188-92.Abstract
We prospectively studied 110 consecutive patients with intertrochanteric hip fractures treated with the 130 degree angle, 10-mm short IMHS intramedullary hip screw (IMHS, Smith & Nephew, Richards, Memphis, TN). Surgery was performed within 36 hours from admission; all patients were mobilized immediately postoperatively. Fracture union, pre- and post-operative mobility status and complications were evaluated. Eighty patients were included in the postoperative evaluation for a mean followup of 14 (range, 9 to 25) months. Mortality was 19%. Union occurred in 79 fractures within 6 months from surgery; there was one case of screw cut-out and one case of deep venous thrombosis. Periprosthetic femoral shaft fractures were not observed. At the latest examination, the mean mobility score decreased from 8.4 +/- 1.6 to 7.1 +/- 2.1 (p = 0.0001); 26 patients (32%) fully achieved the preoperative mobility score and 54 patients (68%) achieved more than 90% of the preoperative mobility score. The IMHS intramedullary hip screw represents a reliable method for the treatment of patients with intertrochanteric hip fractures, and provides for early mobilization and rehabilitation of the patients with acceptable complications.
Nikolaou VS, Petit A, Debiparshad K, Huk OL, Zukor DJ, Antoniou J. Metal-on-metal total hip arthroplasty - five- to 11-year follow-up. Bull NYU Hosp Jt Dis. 2011;69 Suppl 1:S77-83.Abstract
Metal-on-metal (MoM) total hip arthroplasty (THA) has been introduced in an attempt to reduce the wear rate and the consequent osteolysis around implants. The aim of this study was to present the intermediate to long-term clinical and radiological outcomes and to investigate the metal ion levels in the blood of patients who had undergone primary uncemented MoM THA in our institution. Between July 1997 and November 2003, 166 patients (193 hips), with a mean age of 50 years (range, 18-65 years), underwent primary MoM THA. Clinical data, radiographs, and blood samples were obtained at regular follow-up visits. Cobalt (Co), chromium (Cr), and molybdenum (Mo) ions were measured by inductively coupled plasma-mass spectrometry (ICP-MS) from the patient's whole blood. All patients were prospectively followed for a minimum of 5 years (mean, 7 years; range, 5-11 years). The mean Harris hip score (HHS) and the University of California at Los Angeles (UCLA) activity score at the latest follow-up was 88 ± 11 and 7 ± 1.8 points, respectively. Thirteen hips have been revised. Ten acetabular components had early failure, due to factory manufacturing problems. All other implants have been found stable, with no signs of aseptic loosening. The probability of survival at 11 years, if the hips that were revised due to manufacturing problems were excluded, was 98.4%. The Co and Cr metal ion levels, after increasing significantly during the first 4 to 5 years post-surgery, remained stable, with a tendency to decrease thereafter, but not significantly. During the same follow-up period, Mo ion levels remained stable. In this 5-to-11 year follow-up study of MoM THA patients, excellent survivorship, with low complications rates, was found. Results of longer follow-up studies are necessary to clarify the possible long-term effects of metal ion release.
Nikolaou VS, Stengel D, Konings P, Kontakis G, Petridis G, Petrakakis G, Giannoudis PV. Use of femoral shaft fracture classification for predicting the risk of associated injuries. J Orthop Trauma. 2011;25(9):556-9.Abstract
OBJECTIVES: To investigate the hypothesis that specific fracture patterns in patients with femoral shaft fractures can predict the likelihood of associated injuries. DESIGN: Retrospective cohort study. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: Consecutive patients treated because of a traumatic diaphyseal femoral fracture. MAIN OUTCOME MEASUREMENT: We studied the association between the Orthopaedic Trauma Association (OTA) fracture classification (derived from initial radiographs) and concomitant injuries of the head, spine, chest, abdomen, and pelvis with a severity of two or more points according to the Abbreviated Injury Scale by logistic regression analysis. RESULTS: One hundred forty-three of 203 patients (80 men, 63 women; mean age 54 ± 26 years) met the inclusion criteria. All patients had unilateral diaphyseal fractures, 64 OTA 32.A (45%), 46 OTA 32.B (32%), and 33 OTA 32.C (23%). In addition, 134 associated injuries were identified in 52 patients. Increasing fracture severity, as expressed by the OTA classification (ie, A, B, C), was significantly associated with a higher likelihood of thoracic (odds ratio [OR], 5.89; 95% confidence interval [CI], 2.59-13.40), pelvic (OR, 4.55; 95% CI, 2.01-10.28), upper (OR, 2.38; 95% CI, 1.27-4.48), and lower extremity injuries (OR, 3.12; 95% CI, 1.78-5.46). Fracture severity explained between 70% and 86% of the probability of having accompanying injuries. CONCLUSION: Radiographic grading of the severity of a femoral shaft fracture may signal the presence of accompanying injuries and should contribute to the clinical decision-making process in severe trauma.
Tsiolis P, Giamarellos-Bourboulis EJ, Mavrogenis AF, Savvidou O, Lallos SN, Frangia K, Lazarettos I, Nikolaou V, Efstathopoulos NE. Experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus treated with a polylactide carrier releasing linezolid. Surg Infect (Larchmt). 2011;12(2):131-5.Abstract
BACKGROUND: The effectiveness of a new delivery system consisting of polymerized dilactide (PLA) with incorporated linezolid was investigated in a rabbit model as a means of treating methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis. METHODS: The PLA-linezolid system was prepared after thorough stirring of PLA with linezolid at a 10:1 ratio. Experimental osteomyelitis was established in 40 rabbits by a modification of the Norden model with MRSA as the test isolate. After a hole had been drilled in the upper right femur, the isolate was inoculated using a thin needle working as a foreign body. At three weeks, the needle was removed and cultured, and the PLA-linezolid system was implanted in half the animals (group B); the remaining half was the control group (group A). Animals were sacrificed at regular intervals; tissue around the site of implantation was examined for pathologic changes and cultured quantitatively. RESULTS: The prepared system eluted linezolid in vitro at concentrations much greater than the minimum inhibitory concentration (MIC) of the test pathogen for 11 days. At three weeks after inoculation of the test isolate, all animals had osteomyelitis. By the sixth week, bacterial growth from cancellous bone of group B was significantly lower than that in group A. However, this effect was not maintained until the end of the study (weeks 8 and 10), when the differences in bacterial growth in the two groups were not significant. CONCLUSION: Polymerized dilactide mixed with 10% linezolid achieved partial arrest of the offending pathogen in an experimental model of osteomyelitis caused by MRSA.