Wiktor Urbanski

Cytokine induction of sol–gel-derived TiO 2 and SiO 2 coatings on metallic substrates after implantation to rat femur

Material surface is a key determinant of host response on implanted biomaterial. Therefore, modification of the implant surface may optimize implant–tissue reactions. Inflammatory reaction is inevitable after biomaterial implantation, but prolonged inflammation may lead to adverse reactions and subsequent implant failure. Proinflammatory activities of cytokines like interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) are attractive indicators of these processes and ultimately characterize biocompatibility. The objective of the study was to evaluate local cytokine production after implantation of stainless steel 316L (SS) and titanium alloy (Ti6Al4V) biomaterials coated with titanium dioxide (TiO2) and silica (SiO2) coatings prepared by sol–gel method. Biomaterials were implanted into rat femur and after 12 weeks, bones were harvested. Bone–implant tissue interface was evaluated; immunohistochemical staining was performed to identify IL-6, TNF-α, and Caspase-1. Histomorphometry (AxioVision Rel. 4.6.3 software) of tissue samples was performed in order to quantify the cytokine levels. Both the oxide coatings on SS and Ti6Al4V significantly reduced cytokine production. However, the lowest cytokine levels were observed in TiO2 groups. Cytokine content in uncoated groups was lower in Ti6Al4V than in SS, although coating of either metal reduced cytokine production to similar levels. Sol–gel TiO2 or SiO2 coatings reduced significantly the production of proinflammatory cytokines by local tissues, irrespective of the material used as a substrate, that is, either Ti6Al4V or SS. This suggests lower inflammatory response, which directly points out improvement of materials’ biocompatibility.

Increased Radiation but No Benefits in Pedicle Screw Accuracy With Navigation versus a Freehand Technique in Scoliosis Surgery

Background The clinical value of pedicle screws in spinal deformity surgery is well known; however, screw insertion is demanding and sometimes associated with complications. Navigation systems based on intraoperatively obtained three-dimensional (3-D) images were developed to minimize pedicle screw misplacements. However, there is a lack of data confirming superiority of navigation above other techniques. There are also concerns regarding increased radiation used during the procedure. Questions/purposes The purposes of this study were (1) to compare accuracy of the two methods of pedicle screws placement: intraoperative 3-D image navigation versus a freehand technique in patients with idiopathic scoliosis; and (2) to assess the radiation dose received by patients with both methods. Methods Between 2014 and 2016, 49 patients underwent posterior spinal fusion with all pedicle screw constructs for idiopathic scoliosis performed by two surgeons. The study design involved alternating the use of the freehand technique and navigation to position pedicle screws in consecutive patients, forming groups of 27 patients with 451 navigated screws and 22 patients with 384 screws positioned freehand. The two groups did not differ in age, sex, or magnitude of deformity. Two observers not involved in the treatment evaluated the position of the screws. The pedicle breach was assessed on intraoperatively obtained 3-D O-arm® scans according to a grading system: Grade 0 = no pedicle wall violation; Grade 1 = perforation ⩽ 2 mm; Grade 2 = 2 to 4 mm; and Grade 3 = perforation > 4 mm. Grades 0 and 1 were considered properly positioned and Grades 2 and 3 represented malposition. Results In terms of accuracy, we found no differences, with the numbers available, between the freehand and navigated groups in terms of the proportion of screws that were properly positioned (96% freehand and 96% in the navigation group, respectively; p = 0.518). Grade 3 pedicle screws were observed only in the freehand group and were all located in the upper thoracic spine. Patients undergoing navigated pedicle screw placement received a greater mean radiation dose than those whose screws were placed freehand (1071 ± 447 mGy-cm versus 391 ± 53 mGy-cm; mean difference, 680 mGy-cm; 95% confidence interval, 217-2053 mGy-cm; p < 0.001). Conclusions In patients with moderate idiopathic scoliosis undergoing primary surgery, we did not observe benefits of pedicle screw placement with CT-based navigation, but the patients experienced greater exposure to radiation. Level of Evidence Level III, therapeutic study.

Methods of reducing allogeneic blood demand in orthopedic surgery.

Despite advances in this field, allogeneic blood transfusion still carries a lot of risk; the availability of heterologous blood is also constantly decreasing. We describe the most popular methods for reducing the allogeneic blood requirement. Basic information is presented about the physiological mechanisms of compensation for intraoperative blood loss, which can be compromised by respiratory and cardiovascular disease or infections. Preoperative anemia (manifested by low hemoglobin levels) is statistically the most significant factor that increases the need for allogeneic blood transfusion. This paper evaluates the importance of oral and intravenous iron supplementation in the perioperative period, and the use of erythropoietin to boost Hb levels. Minimizing intraoperative blood loss also decreases the need for transfusion, and may be accomplished via meticulous hemostasis, an appropriate surgical approach, atraumatic surgical technique, reduced surgery time, and rational tourniquet use. Controlled intraoperative hypotension is a method of proven efficacy. Synthetic antifibrinolytic agents are also used to reduce perioperative blood loss; however, few clinical trials have focused on the use of such drugs in orthopedics. The use of postoperative drainage is still debatable. The allogeneic blood requirement can also be reduced by autologous blood transfusion. Autologous transfusion can be accomplished by preoperative autotransfusion, preoperative hemodilution, and intra- or postoperative blood salvage. It is currently the safest method of compensating for perioperative blood loss, avoiding all the described risks of heterologous blood transfusion.

Balance and lower limb loads distribution after Ilizarov corticotomy

INTRODUCTION Normal balance and symmetric distribution of lower limb loads are associated with adequate muscle strength, joint mobility and proprioception. The aim of this study was to analyze the distribution of lower limb loads and balance prior to and after axis correction and lengthening with Ilizarov method. MATERIALS AND METHODS The prospective analysis included 20 patients from our clinic, who have been subjected to distraction-corrective lower limb corticotomies with the Ilizarov method in 2014-2015. Balance and distribution of lower limb loads were determined with a pedobarographic platform. RESULTS Prior to the surgery, mean loads on affected and non-affected limbs corresponded to42%and58%of body weight, respectively. Mean loads on affected and non-affected limbs during the postoperative examination did not differ significantly. Mean path length of the center of gravity prior to and after the surgery amounted to143.27 cm and 125.11 cm, respectively. Mean area of the center of gravity was 7.81 cm2prior to the surgery and 5.81 cm2after the procedure. DISCUSSION Our present study showed that distraction-corrective Ilizarov corticotomy may provide more symmetric distribution of lower limb loads and improvement of balance. This outcome should be considered satisfactory from the perspective of the locomotor system statics. Corticotomies with Ilizarov method provide symmetric distribution of loads between non-affected and operated limb.

Sport and physical activity after ankle arthrodesiswith Ilizarov fixation and internal fixation

BACKGROUND Severe osteoarthritis (OA) of the ankle joint constitutes an important social problem. OBJECTIVES We used (1) the GRIMBY scale, (2) the LOWER LIMB Activity scale, (3) the UCLA (University of California Los Angeles) activity scale, (4) the VAS (visual analogue scale) ACTIVITY scale, and (5) the FAAM (foot and ankle ability measure) SPORT scale to verify whether the type of ankle joint arthrodesis stabilization affected sports and physical activity levels. MATERIAL AND METHODS We carried out a prospective clinical study of 47 patients who had undergone ankle arthrodesis with Ilizarov external fixator stabilization (Group 1, n = 21) or internal stabilization with screws (Group 2, n = 26) at Orthopaedic Clinic at the Wroclaw Medical University, Poland, from 2007 to 2015. Sports and physical activity levels were measured by (1) the GRIMBY scale, (2) the LOWER LIMB Activity scale, (3) the UCLA activity scale, (4) the VAS ACTIVITY scale, and (5) the FAAM SPORT scale. RESULTS A comparison between the average results of Group 1 and Group 2 on the LOWER LIMB Activity scale and the GRIMBY scale before and after surgery revealed no significant differences. In Group 1, the mean scores on the VAS ACTIVITY scale and the UCLA activity scale after treatment were higher than in Group 2. In Group 1, the mean outcome in the SPORT FAAM scale after treatment was 40; in Group 2 it was 30.06. CONCLUSIONS Ilizarov fixation of ankle arthrodesis is associated with better scores on the FAAM SPORT, UCLA activity and VAS ACTIVITY scales after treatment than internal fixation. The scores on the GRIMBY scale and the UCLA activity scale were significantly higher after treatment than before treatment in both groups. In this study, ankle fusion with Ilizarov fixation and internal fixation was found to be effective in the treatment of ankle arthritis. The levels of sport and physical activity were satisfactory in both groups, but the outcomes after fixation with the Ilizarov apparatus were better than after internal stabilization.

Radiological evaluation of ankle arthrodesis with Ilizarov fixation compared to internal fixation

INTRODUCTION We asked whether the type of ankle joint arthrodesis stabilization will affect: (1) rate of union, (2) rate of adjacted-joint arthritis, (3) malalignment of the ankle joint. MATERIAL AND METHODS We retrospectively radiological studied 62 patients who underwent ankle arthrodesis with Ilizarov external fixator stabilization (group 1,n=29) or internal stabilization (group 2,n=33) from 2006 to 2015. Radiologic outcomes were mesure by: (1) rate of union, (2) rate of adjacent-joint arthritis, (3) malalignment of the ankle joint. The Levenes test,Mann-Whitney U test and Students t-test were used to the statistical analyses. RESULTS Ankle fusion was achieved in 100% of patients treated with external fixation and in 88% with internal stabilization. Desired frontal plane alignment was achieved in 100% of patients with external fixation and 76% with internal stabilization. Desired sagittal plane alignment was achieved in 100% of external fixation and 85% of internal stabilization. A total of 14 (48.3%) patients from group 1 showed a radiographic evidence of pre-existing adjacent-joint OA. The radiographic evidence of pre-existing adjacent-joint OA was also found in 27(81.8%) subjects from group 2. Alterations of adjacent joints were also found on postoperative radiograms of 19 (65.5%) patients subjected to Ilizarov fixation and in all 33 patients from group 2. DISCUSION Ilizarov fixation of ankle arthrodesis is associated with lower prevalence of adjacent-joint OA and ankle joint misalignment,and with higher fusion rates than after internal fixation.Although achieving a complex ankle fusion is generally challenging,radiological outcomes after fixation with the Ilizarov apparatus are better than after internal stabilization.

Assessment of the distribution of load on the lower limbs and balance before and after ankle arthrodesis with the Ilizarov method

Ankle arthrodesis with the Ilizarov method is an accepted form of treatment of advanced degenerative changes of the ankle joint. Incorrect balance and load distribution on the lower limbs may result in pain and dysfunction. The aim of the study was to assess the change of balance and load distribution in lower extremities in patients before and after ankle arthrodesis with the Ilizarov method. Between 2013 and 2016, ankle arthrodesis using the Ilizarov method was performed on 21 patients. The evaluation of balance and percentage of load in each lower limb was performed before the surgery and during the follow-ups. The evaluation was performed using a Zebris pedobarographic platform. Before the surgery, the patients exhibited an average load of 41.9% of body weight in the affected limb, whereas the load in the healthy limb was 58.1%. The difference was statistically significant (p = 0,000031). In two years follow-up, the average load in the treated limbs was 48.19%, whereas the healthy limbs were subjected to an average load of 51.81%. In preoperative tests, the average path length of the center of gravity was 161.55 cm; postoperatively, the average path length of the center of gravity was 129.7 cm (p = 0.00003206). Preoperatively, the average area of the center of gravity was 18.85 cm2; it decreased to 6.19 cm2 (p = 0.000032) postoperatively. Arthrodesis of the ankle with the Ilizarov method improved the statics of the musculoskeletal system by improving the distribution of loads in the lower limbs as well as balance. However, it failed to restore the parameters of a healthy person. Advanced degenerative changes of the ankle disturb the biomechanics of the entire lower limb.

The Impact of Direct Vertebral Rotation (DVR) on Radiographic Outcome in Surgical Correction of Idiopathic Scoliosis

Introduction: Recent developments of spinal instruments allow to address nearly all components of idiopathic scoliosis. Direct vertebral rotation (DVR) maneuver was introduced to correct apical axial vertebral rotation. It is however still not well established how efficiently DVR affects results of scoliosis correction. The object of the study was to evaluate en bloc apical vertebral rotation (DVR) and its impact on coronal and sagittal correction of the spine in patients undergoing surgical scoliosis treatment. Material and methods: 36 consecutive patients who underwent posterior fusion with pedicle screws only constructs for idiopathic scoliosis. 15 patients (20 curves) were corrected by rod derotation only and 21 patients (26 curves) had both rod derotation and DVR. Curve measurements were performed on x-rays obtained before and post operatively - coronal curves, kyphosis (T2-T12, T5-T12). Spine flexibility was assessed on prone bending x-rays. Apical axial rotation was determined on CT scans obtained intraoperatively and postoperatively. Rotation angle (RAsag) was measured according to Aaro and Dahlborn. Results: We observed reduction of RAsag in all patients, however in DVR group decrease was greater, by 31.8% comparing to non-DVR group, by 8.6% (p=0.0003). Mean coronal correction in DVR group was 68.8% and in rod derotation group without DVR 55% (p=0.002). No significant correlation was found between degree of derotation obtained and coronal correction. In DVR group T2-T12 kyphosis has increased in 28 (65%) patients whereas in non DVR group in 31 (69%) cases. Mean value of T2-T12 kyphosis growth was 16.7% in DVR and 22.1% in non DVR group. These differences however did not occur statistically significant. Conclusions: Direct vertebral rotation (DVR) manoeuvre reduces significantly apical rotation of the spine, enhances ability of coronal correction and it does not reduce thoracic kyphosis.

Efficacy of En Bloc Direct Vertebral Body Derotation (Dvbd) in Idiopathic Scoliosis Treatment

Introduction Vertebral axial rotation in horizontal plane is a component of spinal deformity in scoliosis. Greater axial rotation is related with inclination to curve progression, contributes to rib hump development. Therefore the correction of axial deformity appears as an obvious component of scoliosis correction. However clinical efficiency and complication risk of derotation maneuvers is still not established. The object of the study was to assess horizontal correction obtained with en bloc direct vertebral body derotation (DVBD) and the influence of the maneuver on coronal and sagittal correction of the spine in patients undergoing surgical scoliosis correction. Material and Methods 36 patients after surgical correction of idiopathic scoliosis were included into study. Authors analyzed two groups; adolescents and adults. All patients underwent posterior fusion with pedicle screws only instrumentation. 15 (20 curves) patients were corrected by rod derotation only and 21 (26 curves) underwent rod derotation and direct en bloc vertebral derotation (DVBD). Measurements according to Cobb method were performed on X-rays obtained before and post surgery - coronal plane curves, sagittal profile (T2-T12, T5-T12, L1-S1). Spine flexibility was assessed of prone bending X-rays. Axial rotation was determined on CT scans obtained intraoperatively (O-Arm, Medtronic) and postoperative CT scan. Rotation assessment was done according to the method described by Aaro and Dahlborn. Results The comparison of axial rotation prior to correction and post correction revealed decrease of axial apical vertebral rotation in both DVBD and non DVBD groups. However in DVBD group vertebral derotation was greater than in non DVBD group and it was confirmed in statistic analysis. Amount of axial derotation was similar in both adults and adolescents. Analysis of coronal curves showed statistically significant better correction in (DVBD) group and obviously better correction was possible in flexible than stiff curves. DVBD did not improve but also did not decrease kyphosis comparing to pre op measurements and results from non DVBD group. This statement concerned both T2-T12, T5-T12 measurements. Neither flexibility nor stiffness of the curves influenced kyphosis results. Conclusion Direct vertebral body derotation is a relevant maneuver to improve correction in idiopathic scoliosis, either in coronal or sagittal plane. It may be useful technique in adolescent as well as adult patients.

Pedicular Screw Placement Accuracy with O-Arm Based Navigation in Patients with Scoliosis

Introduction Application of transpedicular screws to obtain posterior spinal fusion in thoraco-lumbar spine has become standard in spinal surgery. However technique of screws insertion is demanding and not free of complications. Positioning is particularly challenging in pediatric patients with spinal deformity. Navigation systems based on intraoperatively obtained 3D image seem to be very promising solution to prevent or at least minimize screw misplacements. Although still lack of data confirming superiority of navigation above other techniques. The study was designed to assess the accuracy of transpedicular screws placement with O-arm and navigation in patients who underwent surgery for idiopathic scoliosis. Material and Methods 451 screws in 27 patients were evaluated. All the screws were positioned by two surgeons (WU, WJ) with aid of navigation (Stealth Station, Medtronic) based on 3D image obtained during surgery (O-ARM, Medtronic). The accuracy was described separately for each screw based on postoperatively obtained CT scans. The assessment was made according to widely accepted grading system: grade 0 – no pedicle wall violation, grade 1 =< 2 mm perforation, grade 2 – wall perforation with half of the diameter of the screw outside of the pedicle (=< 4 mm), grade 3 complete perforation of the pedicle (>5 mm). The comparison of accuracy was made between adults (13 patients) and adolescents (14 patients). Results In the study authors reported overall accuracy of 96% correctly positioned pedicle screws (83% grade 0 and 13% grade 1). No grade 3 screws were reported. Statistical analysis confirmed decreased accuracy in upper thoracic level (82% of grade 0 and 1). No statistically significant differences in implant accuracy were observed between adults (96.2% of grade 0 and 1) and adolescents (95.3% of grade 0 and 1). Conclusion The application of navigation system is a safe method of pedicle screws introduction either in adults or adolescents. However the technique does not eliminate misplacement. Significant misplacement rate is still observed in upper thoracic spine.