Anteroposterior Plane Research Articles

Geometrical characteristics after Y-stenting of the basilar bifurcation.

We aimed to investigate the angular changes after Y-stenting of the basilar bifurcation aneurysms. A total of 19 patients (age range, 27-80 years; mean age, 52.5 years) underwent Y-stent coiling for basilar bifurcation aneurysm. Three vascular angles (α, β1, β2) were measured in the anteroposterior plane. β1 and β2 represented the angles between the basilar artery and the proximal P1 segments of the right and left posterior cerebral arteries, respectively. α represented the complementary angle between the β1 and β2 angles. Angles were measured before and after stent deployment. Diameters of the basilar artery and P2 segment of the posterior cerebral artery were measured at both sides. Correlation between vascular diameter and angular change of the basilar bifurcation was investigated. Statistically significant α, β1, and β2 angle changes were found after stent deployment (P < 0.001). There was no statistically significant relationship between the diameter of the basilar artery and the α, β1, β2 angle changes (P > 0.05). There was no statistically significant relationship between the diameter of the posterior cerebral artery and the β angle change (P > 0.05). We found a statistically significant inverse correlation between pre-stent β angle and post-stent angle change (right side, P = 0.008; left side, P < 0.001). Y-stenting narrows the effective neck and straightens the vascular bifurcation angle. Most of the angular remodeling occurs on the side that had a more acute angle before stent deployment.

Quantification of the Balance Error Scoring System with Mobile Technology.

The aim of this project was to develop a biomechanically based quantification of the Balance Error Scoring System (BESS) using data derived from the accelerometer and gyroscope of a mobile tablet device. Thirty-two healthy young adults completed the BESS while an iPad was positioned at the sacrum. Data from the iPad were compared to position data gathered from a three-dimensional motion capture system. Peak-to-peak (P2P), normalized path length (NPL), and root mean squared (RMS) were calculated for each system and compared. Additionally, a 95% ellipsoid volume, iBESS volume, was calculated using center of mass (CoM) movements in the anteroposterior (AP), mediolateral (ML), and trunk rotation planes of movement to provide a comprehensive, 3D metric of postural stability. Across all kinematic outcomes, data from the iPad were significantly correlated with the same outcomes derived from the motion capture system (rho range, 0.37-0.94; P < 0.05). The iBESS volume metric was able to detect a difference in postural stability across stance and surface, showing a significant increase in volume in increasingly difficult conditions, whereas traditional error scoring was not as sensitive to these factors. The kinematic data provided by the iPad are of sufficient quality relative to motion capture data to accurately quantify postural stability in healthy young adults. The iBESS volume provides a more sensitive measure of postural stability than error scoring alone, particularly in conditions 1 and 4, which often suffer from floor effects, and condition 5, which can experience ceiling effects. The iBESS metric is ideally suited for clinical and in the field applications in which characterizing postural stability is of interest.

The Endoscopic Endonasal Approach to the Hypoglossal Canal: The Role of the Eustachian Tube as a Landmark for Dissection.

Improvements in endoscopic technology and reconstructive techniques have made the endoscopic endonasal approach (EEA) a viable option to approach ventromedial lesions in the region of the hypoglossal canal. Prior to contemplating this surgical corridor, a thorough understanding of anatomic relationships and landmarks is essential to safely approach this region of the posterior skull base through an EEA. To describe the surgical technique and anatomic landmarks in the EEA to the hypoglossal canal through referencing nasopharyngeal and posterior skull base anatomy. Study of latex-injected cadaveric heads at the North Carolina Eye Bank Multidisciplinary Surgical Skills Laboratory at the University of North Carolina. An EEA to the hypoglossal canal was carried out bilaterally in 5 embalmed, latex-injected cadaver heads. Cadaveric measurements of anatomic landmarks and relationships in the approach were obtained using a 10-cm surgical ruler and were reported as mean distances. Additionally, high-quality endoscopic images demonstrating the operative technique and anatomic relationships were obtained. The distance between the lacerum segment of the internal carotid arteries, the superolateral boundary, was 23.6 mm (SD, 11.8 mm). The distance between the anterolateral edge of the occipital condyles, the inferolateral boundary, was 19 mm (SD, 0.80 mm). The supracondylar groove was identified in the same anteroposterior plane as the nasopharyngeal orifice of the eustachian tube, and the anterior-most edge of the occipital condyle was 14 mm (SD, 0.82 mm) from the posterosuperior edge of the salpingopharyngeal fold. Additionally, the transtubercular corridor was on the same plane as the superior edge of the torus tubarius in the anteroposterior axis. The distance to the hypoglossal canal from midline was 10 mm, which was found after completing drilling in the transcondylar and transtubercular corridors. Last, the hypoglossal nerve rootlets were identified entering the canal 6 mm inferiorly and 8 mm laterally from the vertebrobasilar junction. The eustachian tube and other elements of nasopharyngeal anatomy are fixed landmarks that provide important points of reference when approaching the hypoglossal canal through an EEA. A thorough understanding of these anatomic relationships is vital in safely navigating this direct, surgical corridor to the posterior fossa.

Femoral Neurogram Before Transpsoas Spinal Access at L4–5 Intervertebral Disk Space

Observational study. To illustrate the variability of the course of the femoral nerve across the L4-5 disk space, and to present a novel application of transforaminal epidural steroid injections (TFESI) in the visualization of femoral nerve roots. A concern regarding the lateral retroperitoneal transpsoas approach is the proximity of the lumbar plexus. Current techniques of assessing the proximity of neural tissue to the L4-5 disk space have limited capabilities. A total of 100 patients were selected for L4-5 TFESI (L4 selective nerve root blocks) because of lumbar radiculopathy. L4 neurograms were obtained while performing L4-5 TFESI under flouroscopic guidance, using a retroneural technique. The course of the L4 root/femoral nerve was then evaluated under fluoroscopy in the anteroposterior and lateral planes. Images were then reviewed by a radiologist, physiatrist, and 2 orthopedic spine surgeons. Fluoroscopic evaluation revealed that the pattern of location of the femoral nerve was highly variable. In males, it was located 4.7% in zone 2, 32.5% in zone 3, 53.5% in zone 4, and 9.3% in zone P. In female patients, it was located 7.0% in zone 2, 14% in zone 3, 54.4% in zone 4, and 24.6% in zone P. An L4 neurogram will provide an accurate trajectory of L4 root/femoral nerve as it crosses the L4-5 intervertebral disk space. An accurate assessment is essential to help minimize the increasing frequency of thigh pain, paresthesias, and weakness associated with the lateral access to the L4-5 intervertebral disk space. Femoral nerves that fall within zones 2 and 3 will require more manipulation during retraction and may be better suited with a different surgical approach.

The programmable hexapod

The Gough-Stewart platform (GSP) is a variable strut, programmable octahedral hexapod that uses six computer-controlled linear actuators to support a moveable base. These devices have been developed for a wide range of commercial uses including flight and vehicle simulators, high-precision tools, mining machines and medical instruments including programmable external fixators. The prototype hexapod external was introduced in France in 1986 and improvements in component design and computer algorithms have broadened the clinical repertoire of these devices. An increase in the number of available systems is expected in the next 18 months, owing to the expanding indications for this technology, in addition to termination of long standing patent arrangements and the associated commercial imperatives. These versatile platforms have clinical applications in acute fracture fixation; deformity surgery and limb salvage and provide an attractive combination of flexibility and ease of application. Contemporary orthopaedic practice is illustrated by two-dimensional radiological images, presented in standard anteroposterior and medio-lateral orthogonal planes. These are simplified ‘two axis’ representations of complex three-dimensional objects. It would not be possible to use an automated device to predictably reconstruct a deformed bone without the ability to mathematically describe the positions of the individual components. Pythagoras (c.570 BCE – c.495 BCE) and Euclid (c.300 BCE) are credited with defining the fundamentals of 2D and 3D geometry, and this was refined by Appolonius (c.262 BCE – c. 190 BCE), who anticipated Cartesian geometry by 1800 years. Pappus (c. A.D. 290 – c. 350) introduced a formalised approach to this area of mathematics and described a form of geometry that was not based on the concept of distance. This began with the study of the relationship between points and lines in 2D space and developed into the discipline of projective geometry. The introduction of realism in art in the Italian Renaissance relied on …

Electromagnetic navigation-guided surgery in the semi-sitting position for posterior fossa tumours: a safety and feasibility study.

Electromagnetic (EM)-guided neuronavigation is an innovative technique and a viable alternative to opto-electric navigation. We have performed a safety and feasibility study using EM-guided neuronavigation for posterior fossa surgery in the semi-sitting position in a selected subset of patients. Out of 284 patients with posterior fossa tumours operated upon over a period of 40 months, a subset of 15 patients was thought to possibly benefit from EM navigational guidance and was included in this study. There were six children and nine adults (aged between 8 and 84 years; mean age, 34.6 years) with different neoplasms in the brainstem or close to the midline. All patients had contrast-enhanced three-dimensional (3D) magnetic resonance imaging (MRI) of the head preoperatively. EM-guided navigation was used to identify and preserve the venous sinuses during craniotomy and to determine the trajectory to the lesion using various approaches. Neuronavigation accuracy was repeatedly checked for deviations measured in millimetres on screen shots during surgery before and after dural opening in the coronal (z = vertical), axial (x = mediolateral) and sagittal (y = anteroposterior) plane. Referencing of the patient in the supine position was fast and easy. There was no loss of navigation accuracy after repositioning of the patient in the semi-sitting position (mean, 2.5 mm ± 0.92 mm). Identification of the pathological structure using EM navigation was achieved in all instances. Optimal angulation of the neck was selected individually to permit a comfortable position for the surgeon with full access to the lesion avoiding over-flexion. Deviation of accuracy at the surface of the target lesion ranged between 2.5 and 5.8 mm (mean, 3.9 mm ± 1.1 mm). EM-guided neuronavigation in the semi-sitting position was safe and technically feasible. It enabled fast and accurate referencing without loss of navigation accuracy despite repositioning of the patient. In contrast to conventional opto-electric neuronavigation there were no line of sight problems.

Endoscopic intracranial surgery enhanced by electromagnetic-guided neuronavigation in children.

Navigated intracranial endoscopy with conventional technique usually requires sharp head fixation. In children, especially in those younger than 1 year of age and in older children with thin skulls due to chronic hydrocephalus, sharp head fixation is not possible. Here, we studied the feasibility, safety, and accuracy of electromagnetic (EM)-navigated endoscopy in a series of children, obviating the need of sharp head fixation. Seventeen children (ten boys, seven girls) between 12 days and 16.8 years (mean age 4.3 years; median 14 months) underwent EM-navigated intracranial endoscopic surgery based on 3D MR imaging of the head. Inclusion criteria for the study were intraventricular cysts, arachnoid cysts, aqueduct stenosis for endoscopic third ventriculostomy (ETV) with distorted ventricular anatomy, the need of biopsy in intraventricular tumors, and multiloculated hydrocephalus. A total of 22 endoscopic procedures were performed. Patients were registered for navigation by surface rendering in the supine position. After confirming accuracy, they were repositioned for endoscopic surgery with the head fixed slightly on a horseshoe headholder. EM navigation was performed using a flexible stylet introduced into the working channel of a rigid endoscope. Neuronavigation accuracy was checked for deviations measured in millimeters on screenshots after the referencing procedure and during surgery in the coronal (z = vertical), axial (x = mediolateral), and sagittal (y = anteroposterior) planes. EM-navigated endoscopy was feasible and safe. In all 17 patients, the aim of endoscopic surgery was achieved, except in one case in which a hemorrhage occurred, blurring visibility, and we proceeded with open surgery without complications for the patient. Navigation accuracy for extracranial markers such as the tragus, bregma, and nasion ranged between 1 and 2.5 mm. Accuracy for fixed anatomical structures like the optic nerve or the carotid artery varied between 2 and 4 mm, while there was a broader variance of accuracy at the target point of the cyst itself ranging between 2 and 9 mm. EM-navigated endoscopy in children is a safe and useful technique enhancing endoscopic intracranial surgery and obviating the need of sharp head fixation. It is a good alternative to the common opto-electric navigation system in this age group.

Subsidence in Single Level Cervical Disc Arthroplasty

Introduction Motion preservation with cervical disc arthroplasty implants has consistently been shown, in numerous randomized controlled trials, to produce equivalent or superior clinical outcomes to anterior cervical decompression and fusion. Therefore, there has been a call, within the spinal surgery community, to compare outcomes between arthroplasty implants. Although it is important to evaluate positive outcomes, it is also of vital importance to analyze complications and assess the potential influence of different implant designs on complications. We have experience in a large series of using several different arthroplasty implants. We have reviewed our series and have identified implants that have subsided. We provide a commentary on these cases. Material and Methods A retrospective review of all single-level anterior cervical decompression and disc arthroplasty cases, performed at the authors' institution, between 2006 and 2012 was conducted. Postoperative X-rays were assessed for any degree of subsidence compared with immediate postoperative X-rays. Cases with evidence of subsidence were studied for potential implicated factors. Results A total of 157 cases were reviewed consisting 64 PRESTIGE LP Cervical Disc System (Medtronic, Minnesota, United States), 51 NUNEC Cervical Arthroplasty System (RTI Surgical, Inc., United States), 35 Discocerv (Scient'x-Alphatec Spine, Arras, France), and 7 other implants in small numbers. Overall, 11 (7%) cases showed evidence of implant subsidence—two (3%) PRESTIGE LP, five (10%) NUNEC, and four (11%) Discocerv. In the cases that subsided, there were three males and eight females. There was a following variety of location of subsidence: anterior, posterior and complete surface of the implant, superior, and inferior. Seven of the cases did not fully cover the disc space in the anteroposterior plane. Three cases appeared to have been impacted into osteophytes posteriorly but subsidence was not necessarily in this location. The majority of cases appeared to have abnormal motion/spondylotic changes in adjacent levels, raising the possibility of abnormal forces being placed through the replaced level. Conclusion Cervical disc arthroplasty implant subsidence may be influenced by implant design, patient factors, and surgical technique. In this series, because of the small number of cases that showed subsidence, we cannot draw any firm conclusions. This report nevertheless should serve as an important stimulus for discussion and development regarding modifiable factors implicated in complications such as device subsidence.

Systematic examination of the fetal abdominal precordial veins: a cohort study.

Examination of the fetal venous system is a necessary part of complete fetal organ scanning to confirm landmark anatomy, such as the ductus venosus and course of the umbilical veins, and, whenever cardiovascular anomalies are identified, to exclude associated anomalous development of the fetal veins. We aimed to develop a protocol for systematic examination of the fetal venous system during midtrimester targeted organ scanning. We included low-risk women with a singleton fetus presenting between January 2011 and June 2013 to our center for routine midtrimester (20-24 weeks) targeted organ scanning. Imaging of the venous system was added to the booked scan and comprised two-dimensional color Doppler scanning of the fetal abdomen in three discrete planes, two transverse and one longitudinal. The more caudal plane was obtained in a ventral or lateral transverse abdominal plane to image the umbilical vein, left portal vein, portal sinus, anterior right portal vein, posterior right portal vein, main portal vein and splenic vein and artery. Moving cephalad, a ventral or lateral transverse plane was obtained to image the right, middle and left hepatic veins and inferior vena cava (IVC). Finally, a longitudinal anteroposterior plane showed the umbilical vein, ductus venosus, IVC and left hepatic vein. In some cases the pulsed Doppler waveform of a given target vessel was also examined. Three-dimensional/4D ultrasound was applied as necessary, when anomalous cases were encountered. We examined 1810 women. Their body mass index ranged from 19 to 40 (mean, 24.7). In 38 (2.1%) women, the target anatomy was not visualized satisfactorily owing to maternal body habitus. A T-shaped configuration of the portal system vessels was observed in 63% of cases, an X-shaped configuration in 25% and an H-shaped configuration in 12%. During the study period, 24 congenital anomalies of the precordial venous system were diagnosed: nine cases of persistent right umbilical vein, seven of agenesis of the ductus venosus, five of anomalous portal venous drainage and three of interrupted IVC with azygos continuation. Examination of the fetal venous system is feasible with the application of three abdominal planes. While a venous system scan is not practicable as part of a screening-level examination, mastery of the normal anatomy is an essential part of the professional knowledge base, in order to provide ready and complete scanning of the system in cases of suspected anomalies or disordered cardiac function.

The effect of frictional torque and bending moment on corrosion at the taper interface : an in vitro study.

The aim of this study was to assess the effect of frictional torque and bending moment on fretting corrosion at the taper interface of a modular femoral component and to investigate whether different combinations of material also had an effect. The combinations we examined were 1) cobalt-chromium (CoCr) heads on CoCr stems 2) CoCr heads on titanium alloy (Ti) stems and 3) ceramic heads on CoCr stems. In test 1 increasing torque was imposed by offsetting the stem in the anteroposterior plane in increments of 0 mm, 4 mm, 6 mm and 8 mm when the torque generated was equivalent to 0 Nm, 9 Nm, 14 Nm and 18 Nm. In test 2 we investigated the effect of increasing the bending moment by offsetting the application of axial load from the midline in the mediolateral plane. Increments of offset equivalent to head + 0 mm, head + 7 mm and head + 14 mm were used. Significantly higher currents and amplitudes were seen with increasing torque for all combinations of material. However, Ti stems showed the highest corrosion currents. Increased bending moments associated with using larger offset heads produced more corrosion: Ti stems generally performed worse than CoCr stems. Using ceramic heads did not prevent corrosion, but reduced it significantly in all loading configurations.

Preoperative tumor size at MRI predicts deep myometrial invasion, lymph node metastases, and patient outcome in endometrial carcinomas.

The aim of this study was to explore the relation between preoperative tumor size based on magnetic resonance imaging (MRI) and the surgical pathologic staging parameters (deep myometrial invasion, cervical stroma invasion, and metastatic lymph nodes) and to assess the prognostic impact of tumor size in endometrial carcinomas. Interobserver variability for the different tumor size measurements was also assessed. Preoperative pelvic MRI of 212 patients with histologically confirmed endometrial carcinomas was read independently by 3 radiologists. Maximum tumor diameters were measured in 3 orthogonal planes (anteroposterior, transverse, and craniocaudal planes [CC]), and tumor volumes were estimated. Tumor size was analyzed in relation to surgical staging results and patient survival. The multivariate analyses were adjusted for preoperative risk status based on endometrial biopsy. Intraclass correlation coefficients and receiver operating characteristics curves for the different tumor measurements were also calculated. Anteroposterior tumor diameter independently predicted deep myometrial invasion (P < 0.001), whereas CC tumor diameter tended to independently predict lymph node metastases (P = 0.06). Based on receiver operating characteristic curves, the following tumor size cutoff values were identified: anteroposterior diameter greater than 2 cm predicted deep myometrial invasion (unadjusted odds ratio [OR], 12.4; P < 0.001; adjusted OR, 6.7; P < 0.001) and CC diameter greater than 4 cm predicted lymph node metastases (unadjusted OR, 6.2; P < 0.001; adjusted OR, 4.9; P = 0.009). Large tumor size was associated with reduced progression/recurrence-free survival (P ≤ 0.005 for all size parameters), and CC diameter had an independent impact on survival (adjusted hazards ratio, 1.04; P = 0.009). The interobserver variability for the different size measurements was very low (intraclass correlation coefficient, 0.78-0.85). Anteroposterior tumor diameter greater than 2 cm predicts deep myometrial invasion, and CC tumor diameter greater than 4 cm predicts lymph node metastases. Tumor size is a strong prognostic factor in endometrial carcinomas. Preoperative tumor measurements based on MRI may potentially improve preoperative risk stratification models and thus enable better tailored surgical treatment in endometrial cancer.

Clinical Evaluation of Efficacy of CIA and CNA Intrusion Arches.

Excessive overbite is one of the most common problems that confront the orthodontist. Deep bite can be due to infraocclusion of posterior teeth, supraocclusion of anterior teeth or a combination of the two. Correction of same can be carried out by extrusion of molars, intrusion of incisors or by a combination of both respectively. Various intrusion arches are recommended for correcting deep bite by true intrusion of anterior teeth, Utility arches, Segmental arch, Connecticut Intrusion Arch (CIA) and Connecticut New Arch (CNA). The purpose of this study was to evaluate clinical efficacy of CIA and CNA intrusion arches. Tracings recorded from pre and post-treatment lateral cephalograms of 25 patients treated by CIA (Group I) and another 25 patients treated by CNA (Group II) intrusion arches in deep bite cases after four months of treatment were analysed and findings were recorded. Paired t-test was used to compare pre and post-treatment changes within Groups I and II and unpaired t-test was used to compare treatment changes between Group I and Group II. A P-value of < 0.05 was set for statistical significance. Findings of this study demonstrate that an average of 1mm of intrusion takes place with CIA intrusion arch and 1.3mm with CNA intrusion arch in a period of 4 months. Both intrusion arches do not affect the position of molar in vertical or anteroposterior plane. Both CIA and CNA intrusion arches are effective in bringing about intrusion of lower incisors.

Perceptual and motor learning underlies human stick-balancing skill.

We investigated the acquisition of skill in balancing a stick (52 cm, 34 g) on the fingertip in nine participants using three-dimensional motion analysis. After 3.5 h of practice over 6 wk, the participants could more consistently balance the stick for longer durations with greatly reduced magnitude and speed of stick and finger movements. Irrespective of level of skill, the balanced stick behaved like a normal noninverted pendulum oscillating under greater-than-gravity torque with simple harmonic motion about a virtual pivot located at the radius of gyration above the center of mass. The control input parameter was the magnitude ratio between the torque applied on the stick by the participant and the torque due to gravity. The participants utilized only a narrow range of this parameter, which did not change with practice, to rotate the stick like a linear mass-spring system. With increased skill, the stick therefore maintained the same period of oscillation but showed marked reductions in magnitude of both oscillation and horizontal translation. Better balancing was associated with 1) more accurate visual localization of the stick and proprioceptive localization of the finger and 2) reduced cross-coupling errors between finger and stick movements in orthogonal directions; i.e., finger movements in the anteroposterior plane became less coupled with stick tip movements in the mediolateral plane, and vice versa. Development of this fine motor skill therefore depended on perceptual and motor learning to provide improved estimation of sensorimotor state and precision of motor commands to an unchanging internal model of the rotational dynamics.

Trunk sway during walking among older adults: Norms and correlation with gait velocity

The aim of this study was to establish quantitative norms for trunk sway during walking for older male and female ambulatory adults at different age groups (65–70, 71–75, 76–80, ≥81). We also assessed the relationship between dynamic trunk sway and gait velocity in older individuals with clinically normal or abnormal gaits. Trunk sway in medio-lateral (roll) and antero-posterior (pitch) planes was measured using a body-mounted gyroscope (SwayStar) during walking on a 4.5m long instrumented walkway. Of the 284 older adults (mean age 76.8, 54.6% women) in this sample, the mean±SD value of roll and pitch angles were 6.0±2.0° and 6.7±2.2° respectively. Older women showed significantly greater trunk sway in both roll and pitch angles than older men (p<0.01). In both men and women, there was no significant association of roll angle with age although gait velocity decreased with increasing age. The relationship between roll angle and gait velocity was U-shaped for the overall sample. Among the subgroup with clinically normal gait, increased roll angle was associated with increased gait velocity (p<0.001). However, there was no significant relationship between roll angle and gait velocity among the subgroup with abnormal gait. Therefore, the relationship between medio-lateral trunk sway and gait velocity differs depending on whether gait is clinically normal.We conclude that trunk sway during walking should be interpreted with consideration of both gait velocity and presence of gait abnormality in older adults.

Effects and after-effects of voluntary intermittent light finger touch on body sway

Effects of light touch on body sway have usually been investigated with some form of constant contact. Only two studies investigated transient sway dynamics following the addition or withdrawal of light touch. This study adopted a paradigm of intermittent touch and assessed body sway during as well as following short periods of touch of varying durations to investigate whether effects and after-effects of touch differ as a function of touch duration. In a modified heel-to-toe posture, 15 blindfolded participants alternated their index finger position between no-touching and touching on a strain gauge in response to low- and high-pitched auditory cues. Five trials of 46s duration were segmented into 11 sections: a 6-s no-touching period was followed by five pseudo-randomly ordered touching periods of 0.5-, 1-, 1.5-, 2-, and 5-s duration, each of which was followed by another 6-s no-touching interval. Consistent with previous research, compared to no-touching intervals sway was reduced during touch periods with touch durations greater than 2s. Progressive reductions in sway were evident after touch onset. After touch withdrawal in the 2-s touch condition, postural sway increased and returned to baseline level nearly immediately. Interestingly, in the 5-s touch condition, reductions in sway persisted even after touch withdrawal in the medio-lateral and antero-posterior plane for around 2.5s and 5.5s, respectively. Our intermittent touch paradigm resulted in duration-dependent touch effects and after-effects; the latter is a novel finding and may result from a more persistent postural set involved in proactive sway control.

An alternative "no resection" technique for posterior mitral leaflet prolapse repair: reverse T-plasty.

Reverse T-plasty is an alternative "no resection" technique for posterior mitral leaflet prolapse repair that is inspired by butterfly resection. It combines mediolateral and anteroposterior plane foldings of the posterior leaflet without any resection and shortens cardiopulmonary bypass and cross-clamping time.

Effects of Localized Muscle Fatigue and Whole Body Fatigue on Postural Control during Single-Leg Stance

The purpose of this study was to investigate the effects of localized muscle fatigue and whole body fatigue on postural control during single-leg stance after impairment induced by heel raise and the Harvard step test. Thirty-eight university students (19 men: age, <TEX>$20.1{\pm}0.2$</TEX> yrs; height, <TEX>$175.0{\pm}5.23cm$</TEX>; weight, <TEX>$66.8{\pm}5.6kg$</TEX>; body mass index, <TEX>$21.8{\pm}1.7kg/m^2$</TEX>, 19 women: age, <TEX>$20.6{\pm}1.1yrs$</TEX> ; height, <TEX>$163.6{\pm}6.7cm$</TEX>; weight, <TEX>$58.8{\pm}4.6kg$</TEX>; body mass index, <TEX>$22.0{\pm}2.2kg/m^2$</TEX>) were participated in this study. Subjects performed a series of single-leg postural tasks prior to, following, and 24 hours after completing: heel raise or the Harvard step test. This study showed that the root mean squared distance and velocity in the anteroposterior and mediolateral planes of the center of pressure decreased significantly due to heel raise exercise-induced fatigue. Furthermore, the root mean squared distance in the anteroposterior and mediolateral planes, and the 95% confidence ellipse area of the center of pressure also decreased significantly 24 hours after completing the Harvard step test. In conclusion, this study showed that both heel raise exercise- and Harvard step exercise-induced fatigue affects postural control during single-leg stance in AP and ML planes. Furthermore, this study suggests that changes in the postural control strategy may have occurred after the fatigue protocols during single-leg stance. Also vision can attenuate the postural deficits associated with the fatigues. In order to clarify these results, further studies using other equipment and variables are necessary.

Effect of running exercise with and without the use of equipment Kangoo Jumps, in postural control: a case study.

Introduction: There is increasing interest from the general population, the search for the most suitable and safe exercise programs. Some equipment, such as Kangoo Jumps (KJ), allow performing exercises with less impact on the joints, and probably infer on postural control. Objective: To investigate the effect of exercise submaximal exercise running with and without the use of equipment KJ on postural control variables. Method: Participated in the study with an individual 20 years old, male, equivalent to 86kg body weight. The test was to evaluate the postural balance using a force platform with bipedal before and after conventional and adapted from Cooper (using the KJ) test support. The equilibrium parameters were recorded: (A- COP in cm2) of displacement of the center of pressure; average swing speed of the COP (MVeloc in cm/s) in the anteroposterior planes (A/P) and medial-lateral (M/L). Results: The results showed that after using the equipment KJ, A-COP (-39.70%) MVeloc the A/P (-20.66%) and M/L (-20.48%) were best compared with the race without using KJ test. Conclusion: It is concluded that after running exercise on submaximal exercise with the use of equipment KJ had become favorable outcome for postural balance. One such reason would be because of its system of absorption and dissipation of impact, which allows a better activation of the proprioceptive system through increasing the speed of afferent estimate. The intervention of this study shows that the use of the KJ has significant equipment to maintain postural stability near control values benefits. However, further studies are needed, due to lack of evidence of the parameters of this equipment and the small number in our sample.

Cephalometric skeletal evaluation of patients with Incontinentia Pigmenti

PurposeThe aim of this study was to evaluate the skeletal characteristics of patients with the rare genetic disease of Incontinentia Pigmenti, by lateral cephalometric analysis on the antero-posterior plane and by frontal cephalometric analysis on the horizontal plane. MethodsLateral skeletal cephalometric analyses were performed according to Steiner for evaluation of antero-posterior direction, and frontal skeletal cephalometric analyses according to Ricketts for evaluation of horizontal direction in 9 patients with IP. Left and right facial widths at the level of the zygomatic arch were also evaluated. The Student t-test was used for paired to a 5% level of significance data. ResultsThe lateral skeletal cephalometric findings were not statistically significant, but the Class II was the most frequent finding (44.4%), followed by Class III (33.3%) and Class I (22.2%). The right maxillo-mandibular width was significantly lower than normal values, and the right facial width was significantly higher than the left, at the level of the zygomatic arch. ConclusionsPatients with IP showed more skeletal discrepancies of Class II and III than Class I malocclusion, and had significant horizontal facial skeletal asymmetries. This should alert health professionals to route these patients for orthodontic assessment and possible therapeutic interventions. However, larger samples are needed to better elucidate if these cephalometric findings can be specifically related to IP.

The Surgeon and his Experience is the Thing!

Dr. Merrill Ritter, an outstanding expert on total knee replacement (TKR), has written an interesting paper evaluating results with posterior cruciate retaining (PCR) and posterior-substituting total knee replacement (PS). His center is a high-volume center for total knee replacement, and the study encompasses results in 8,607 total knee replacements. His findings demonstrate an expected slight increase in flexion for the PS TKR in comparison to the PCR TKR (about 3°) with slightly better function in the PCR TKR. However, the results varied from surgeon to surgeon in the group using these different implants, and this was a major variable in the results. Surgeon results varied and were not consistently better with one implant or another. Some surgeons had excellent results with the PCR knee and others less good results with the PCR knee. The same was true for the PS TKR. This led to the conclusion that surgeon preference and experience with a particular implant was the important variable in patient outcome. Many factors influence the clinical outcome after TKR aside from prosthetic selection. This is particularly true in the high-flexion knee or gender-specific knee where results are not better than with conventional TKR. In the end, it is surgical technique and patient factors which predict the outcome of an arthroplasty far more than prosthetic design in the knee. Soft-tissue balancing in the medial-lateral and antero-posterior planes is key to knee flexion and ultimate function. Surgical experience and attention to technique will determine proper gap balancing which influences patient motion and outcome. PCR knees require careful balancing of the posterior cruciate ligament for knee motion, and a surgeon’s ability to balance this may vary. A comfort zone for improved outcomes exists and will vary from one implant to another for a surgeon. My philosophy has correlated with Dr. Ritter’s findings and was first advocated by Michael Freeman, knee innovator from London. Dr. Freeman taught that a surgeon should find a time-proven prosthesis he knows well and is able to implant consistently with excellent soft-tissue balancing and alignment. The surgeon should not move from implant to implant looking for better outcomes but should excel with a particular design and stay with it. He will be able to obtain better results with it in knees of varying severity including the most deformed. Outcomes, function, pain relief, and range of motion will be better in this setting than attributing poor results to implant design alone. Dr. Ritter has validated this important aspect of knee surgery in determining end results. The long-term controversy of PCR vs PS is less so today and is of less importance than surgical experience and excellence of technique regardless of prosthetic selection.