Effects of Vojta Therapy on the Motor Function of Children with Neuromotor Disorders: Study Protocol for a Randomized Controlled Trial.

BACKGROUND: Infantile cerebral palsy is a neurological pathology that causes great morbidity, mortality, and disability in people who suffer from it, mainly affecting motor development. There are a multitude of non-pharmacological methods or therapies for its treatment. One of the main methods is Vojta therapy. This methodology acts on ontogenetic postural function and automatic postural control. OBJECTIVE: This study aims to demonstrate that there are changes in the motor development of children with cerebral palsy with the application of Vojta therapy. METHODS AND ANALYSIS: This is a randomized controlled trial on the effectiveness of two neurorehabilitation techniques in patients with cerebral palsy conducted at the Physical Medicine and Rehabilitation Service of the Teresa Herrera Maternal and Child Hospital of the A Coruña and Cee Health Area. The study will be conducted from January 2023 to December 2024. There will be two groups: the Vojta therapy group (n = 30) and the conventional physiotherapy group (n = 30). The measurement variables will be gross motor function as measured by the Gross Motor Function Measure (GMFM) and Infant Motor Profile (IMP) scales. ETHICS AND DISSEMINATION: The study was approved by the Research Ethics Committee of the University of Murcia (1823/2018) and Comité de Ética de la Investigación de A Coruña-Ferrol (2022/099). TRIAL REGISTRATION NUMBER: ClinicalTrials.gov; identifier: NCT06092619.

The Accuracy and Absolute Reliability of a Knee Surgery Assistance System Based on ArUco-Type Sensors.

Recent advances allow the use of Augmented Reality (AR) for many medical procedures. AR via optical navigators to aid various knee surgery techniques (e.g., femoral and tibial osteotomies, ligament reconstructions or menisci transplants) is becoming increasingly frequent. Accuracy in these procedures is essential, but evaluations of this technology still need to be made. Our study aimed to evaluate the system's accuracy using an in vitro protocol. We hypothesised that the system's accuracy was equal to or less than 1 mm and 1° for distance and angular measurements, respectively. Our research was an in vitro laboratory with a 316 L steel model. Absolute reliability was assessed according to the Hopkins criteria by seven independent evaluators. Each observer measured the thirty palpation points and the trademarks to acquire direct angular measurements on three occasions separated by at least two weeks. The system's accuracy in assessing distances had a mean error of 1.203 mm and an uncertainty of 2.062, and for the angular values, a mean error of 0.778° and an uncertainty of 1.438. The intraclass correlation coefficient was for all intra-observer and inter-observers, almost perfect or perfect. The mean error for the distance's determination was statistically larger than 1 mm (1.203 mm) but with a trivial effect size. The mean error assessing angular values was statistically less than 1°. Our results are similar to those published by other authors in accuracy analyses of AR systems.

Integration of Square Fiducial Markers in Patient-Specific Instrumentation and Their Applicability in Knee Surgery.

Computer technologies play a crucial role in orthopaedic surgery and are essential in personalising different treatments. Recent advances allow the usage of augmented reality (AR) for many orthopaedic procedures, which include different types of knee surgery. AR assigns the interaction between virtual environments and the physical world, allowing both to intermingle (AR superimposes information on real objects in real-time) through an optical device and allows personalising different processes for each patient. This article aims to describe the integration of fiducial markers in planning knee surgeries and to perform a narrative description of the latest publications on AR applications in knee surgery. Augmented reality-assisted knee surgery is an emerging set of techniques that can increase accuracy, efficiency, and safety and decrease the radiation exposure (in some surgical procedures, such as osteotomies) of other conventional methods. Initial clinical experience with AR projection based on ArUco-type artificial marker sensors has shown promising results and received positive operator feedback. Once initial clinical safety and efficacy have been demonstrated, the continued experience should be studied to validate this technology and generate further innovation in this rapidly evolving field.

Patient-specific instrumentation makes sense in total knee arthroplasty.

INTRODUCTION: Patient-specific instrumentation (PSI) for total knee arthroplasty (TKA) surgery was initially developed to increase accuracy. The potential PSI benefits have expanded in the last decade, and other advantages have been published. However, different authors are critical of PSI and argue that the advantages are not such and do not compensate for the extra cost. This article aims to describe the recently published advantages and disadvantages of PSI. AREAS COVERED: Narrative description of the latest publications related to PSI in accuracy, clinical and functional outcomes, operative time, efficiency, and other benefits. EXPERT OPINION: We have published high accuracy of the system, with a not clinically relevant loss of accuracy, significantly higher precision with PSI than with conventional instruments, and a high percentage of cases in the optimal range and similar to that obtained with computer-assisted navigation, greater imprecision for tibial slope, a significant blood loss reduction, and time consumption, an acceptable and non-significant increase in the cost per procedure, and no difference in complications during hospital admission and at 90 days. We think that PSI will not follow the Scott Parabola and that it will continue to be a valuable type of device in some instances of TKA surgery.

Validity and Absolute Reliability of the Cobb Angle in Idiopathic Scoliosis with TraumaMeter Software.

The Cobb angle value is a critical parameter for evaluating adolescent idiopathic scoliosis (AIS) patients. This study aimed to evaluate a software's validity and absolute reliability to determine the Cobb angle in AIS digital X-rays, with two different degrees of experienced observers. Four experts and four novice evaluators measured 35 scoliotic curves with the software on three separate occasions, one month apart. The observers re-measured the same radiographic studies on three separate occasions three months later but on conventional X-ray films. The differences between the mean bias errors (MBE) within the experience groups were statistically significant between the experts (software) and novices (manual) (p < 0.001) and between the novices (software) and novices (manual) (p = 0.005). When measured with the software, the intra-group error in the expert group was MBE = 1.71 ± 0.61° and the intraclass correlation coefficient (ICC (2,1)) = 0.986, and in the novice group, MBE = 1.9 ± 0.67° and ICC (2,1) = 0.97. There was almost a perfect concordance among the two measurement methods, ICC (2,1) = 0.998 and minimum detectable change (MCD95) < 0.4°. Control of the intrinsic error sources enabled obtaining inter- and intra-observer MDC95 < 0.5° in the two experience groups and with the two measurement methods. The computer-aided software TraumaMeter increases the validity and reliability of Cobb angle measurements concerning manual measurement.

Neurologic Music Therapy Improves Participation in Children With Severe Cerebral Palsy.

Positive effects after neurologic music therapy (NMT) have been described regarding the motor function of children with severe cerebral palsy (CP). This study aimed to quantify improvements in participation, as well as complexity on task-related manual activities in children with severe bilateral CP. This analytic quasi-experimental study exposed 17 children with severe cerebral palsy to 13 NMT sessions to improve motor learning through therapeutic instrumental music performance (TIMP), using principally percussion musical instruments. Hoisan software video recording was used to quantify participation involved in creating music. In addition, the number of active movements performed in each NMT session was quantified. Significant improvements were found in the participation variables "visual contact," "motor participation" and "motor participation repetitions." Significant differences were also found in the subcategory "reaching and stroke," "hitting with the hand" and "grasping and hitting." The use of therapeutic of TIMP in children with severe CP improves participation during manual activities utilizing percussion instruments, therefore increasing the intensity of the psychomotor intervention.

Validity and reliability of a computer-assisted system method to measure axial vertebral rotation.

Background: Axial vertebral rotation and Cobb's angle are essential parameters for analysing adolescent idiopathic scoliosis. This study's scope evaluates the validity and absolute reliability of application software based on a new mathematical equation to determine the axial vertebral rotation in digital X-rays according to Raimondi's method in evaluators with different degrees of experience. Methods: Twelve independent evaluators with different experience levels measured 33 scoliotic curves in 21 X-rays with the software on three separate occasions, separated one month. Using the same methodology, the observers re-measured the same radiographic studies three months later but on X-ray films and in a conventional way. Results: Both methods show good validity and reliability, and the intraclass correlation coefficients are almost perfect. According to our results, the software increases 1.7 times the validity and 1.9 times the absolute reliability of axial vertebral rotation on digital X-rays according to Raimondi's method, compared to the conventional manual measurement. Conclusions: The intra-group and inter-group agreement of the measurements with the software shows equal or minor variations than with the manual method, among the different measurement sessions and in the three experience groups. There is almost perfect agreement between the two measurement methods, so the equation and the software may be helpful to increase the accuracy in the axial vertebral rotation assessment.

Computed Tomography-Based Patient-Specific Instrumentation Loses Accuracy with Significant Varus Preoperative Misalignment.

Patient-specific instrumentation (PSI) has been introduced to simplify and make total knee arthroplasty (TKA) surgery more precise, effective, and efficient. We performed this study to determine whether the postoperative coronal alignment is related to preoperative deformity when computed tomography (CT)-based PSI is used for TKA surgery, and how the PSI approach compares with deformity correction obtained with conventional instrumentation. We analyzed pre- and post-operative full length standing hip-knee-ankle (HKA) X-rays of the lower limb in both groups using a convention > 180 degrees for valgus alignment and < 180 degrees for varus alignment. For the PSI group, the mean (± SD) pre-operative HKA angle was 172.09 degrees varus (± 6.69 degrees) with a maximum varus alignment of 21.5 degrees (HKA 158.5) and a maximum valgus alignment of 14.0 degrees. The mean post-operative HKA was 179.43 degrees varus (± 2.32 degrees) with a maximum varus alignment of seven degrees and a maximum valgus alignment of six degrees. There has been a weak correlation among the values of the pre- and post-operative HKA angle. The adjusted odds ratio (aOR) of postoperative alignment outside the range of 180 ± 3 degrees was significantly higher with a preoperative varus misalignment of 15 degrees or more (aOR: 4.18; 95% confidence interval: 1.35-12.96; p = 0.013). In the control group (conventional instrumentation), this loss of accuracy occurs with preoperative misalignment of 10 degrees. Preoperative misalignment below 15 degrees appears to present minimal influence on postoperative alignment when a CT-based PSI system is used. The CT-based PSI tends to lose accuracy with preoperative varus misalignment over 15 degrees.

Reliability of the posterior condylar offset.

The posterior condylar offset (PCO) has been proposed as a determinant of a postoperative range of motion after total knee arthroplasty, although there is no consensus. This study aimed to demonstrate the error introduced by forcing the femoral rotation to overlap both condyles for the "true" lateral X-ray projection for the PCO measurement. We hypothesize that the angular discrepancy between the posterior femoral cortical reference plane and the posterior condylar axis plane due to rotation invalidates the acquisition of reliable measurements on X-rays. We have measured the PCO in 50 "true" lateral X-rays and compared it with the medial and lateral condyles PCO's assessed on a computed tomography-scan-based three-dimensional (3D) model of each knee. PCO based on the 3D imaging differed significantly between the medial (25.8 ± 3.67 mm) and lateral (16.59 ± 2.92 mm) condyle. Three-dimensional PCO values differ significantly from those determined in the radiographic studies. Also, the mean values of the medial and lateral condyle PCO measurements differed significantly (p < 0.001) with all PCO measurements on radiographs. We have identified a difference between the posterior cortical plane and the posterior condylar axis projections, both on the axial plane with a mean value of 11.23° ± 3.64°. Our data show an interplane discrepancy angle between the posterior femoral diaphyseal cortical and the posterior condylar axis plane (due to the femur's necessary rotation to overlap both condyles) may invalidate the 2D X-ray PCO assessment as a reliable measurement.

The Sagittal Integral Morphotype in Male and Female Rowers.

The goal of this study was to describe the integrated spinal assessment of the sagittal morphotype in rowers to determine whether the intense practice of rowing causes a modification of the sagittal curvatures of the spine, its relationship with the rowing technique, and training background. The second goal was to analyse how the dorsal and lumbar curves behave in the three phases of the rowing gesture, and to determine which phases can be detrimental to the correct development of the spine during growth. We analysed the spine curvatures in the sagittal plane of 29 females and 82 males, which were measured with an inclinometer in standing, slump sitting, maximal trunk flexion and during rowing performance. The average value of thoracic kyphosis in the rowers was 30° (mean, 30 + 8.27°). Thoracic hyperkyphosis was found in only two rowers (1.8%). Lumbar lordosis was within normal range in 84.1% of the males (mean, 27 + 9.57°) and 75.9% of female rowers (mean, 33°). Functional thoracic hyperkyphosis was observed in 57.4% of the males and 17.1% of the females. Functional lumbar hyperkyphosis was observed in 28 of the 69 males (40.5%) and five of 22 females (17.2%). Rowing seems to provide adequate spine alignment in the sagittal plane on standing. The integrated spinal assessment of the sagittal morphotype showed that half or our rowers presented with functional thoracic hyperkyphosis, and 43.2% presented with functional lumbar hyperkyphosis. Spine behaviour during the rowing technique shows that the thoracic kyphosis (98.2%) and lumbar spine (91%) perform within normative ranges and could explain the adequate positioning of the spine in the sagittal plane on standing. Years of rowing training tend to reduce thoracic kyphosis in males.

[Is the implementation of Vojta therapy associated with faster gross motor development in children with cerebral palsy?] / Segíti-e a cerebralis paresisben szenvedo gyermekek bruttó motoros funkcióinak fejlodését a Vojta-módszer?

BACKGROUND AND PURPOSE: Vojta therapy has been reported as clinically beneficial for strength, movement and gross motor activities in individual cases and is being included within the second of three levels of evidence in interventions for cerebral palsy. The goal of this study is to understand the effect of Vojta therapy on the gross motor function. METHODS: Our clinical trial followed a one group, pre-post design to quantify rates of changes in GMFM-88 after a two-months period undergoing Vojta therapy. RESULTS: A total of 16 patients were recruited. Post-intervention acceleration rates of GMFM-88-items acquisition (0.005; p<0.001) and Locomotor Stages (1.063; p<0.0001) increased significatively following Vojta the-rapy intervention. CONCLUSION: In this study, Vojta therapy has shown to accelerate the acquisition of GMFM-88-items and Loco-motor Stages in children with cerebral palsy younger than 18 months. Because functional training was not utilised, and other non-Vojta therapy intervention did not influence the outcome, Vojta therapy seems to activate the postural control required to achieve uncompleted GMFM-88-items.

Clinical value of baseline 18F-FDG PET/CT in soft tissue sarcomas.

BACKGROUND: The use of 18F-FDG Positron emission tomography/Computed tomography (PET/CT) in the initial staging of many cancers is clearly established. Most soft tissue sarcoma (STS) has a high affinity for 18F-FDG, which is why 18F-FDG PET/CT has been proposed as a non-invasive method, useful in diagnosis and follow-up. The standardized uptake value values (SUV), the volume-based metabolic parameters MTV (metabolic tumor volume), and TLG (total lesion glycolysis) determine tumor viability and provide its total volume and the total activity of metabolically active tumor cells. The histological grade is the most important predictor of metastases and mortality associated with STS, and a significant relationship between the metabolic parameters of 18F-FDG PET/CT and the histological grade has been described. METHODS: A retrospective study was conducted on STS patients, who had histological grade according to the FNCLCC (Fédération Nationale des Centres de Lutte Contre Le Cancer) criteria, as well as a baseline PET/CT. SUV (SUVmax, SUVmean, and SUVpeak), MTV, and TLG were quantified. A T-student test was performed to establish the relationship between the metabolic biomarkers and the histological grade. Their usefulness as predictors of the histological grade was verified using receiver operator characteristic (ROC) curves. A survival function study was performed using the Kaplan-Meier method. To assess the prognostic utility of the metabolic biomarkers we use the Log-Rank method. RESULTS: The SUV values were useful to discriminate high-grade STS. We found a significant relationship between the histological grade and the SUV values. SUVmax, SUVpeak, MTV, and TLG were predictors of overall survival (OS). There were no significant differences in the OS for the SUVmean, or in the disease-free survival (DFS) for SUVmax, SUVmean, SUVpeak, MTV, and TLG. CONCLUSIONS: The SUVmax, SUVmean, and SUVpeak values correlate with the HG and are useful to discriminate high-grade from low-grade STS. Patients with high SUVmax, SUVpeak, MTV, and TLG have a significantly lower OS.

Sagittal Integral Morphotype of Competitive Amateur Athletes and Its Potential Relation with Recurrent Low Back Pain.

Athletes have higher thoracic and lumbar curvature in standing than the reference values of the non-athletic population. The sagittal integral morphotype method (SIM) assessment has not previously been applied to competitive amateur athletes (CAA). The propose of the present study was to determine the SIM of CAA treated at a sports-medicine center and to identify spinal misalignments associated with recurrent low back pain (LBP). An observational analysis was developed to describe the SIM in 94 CAA. The thoracic and lumbar curvatures of the CAA were measured in standing, sitting, and trunk forward flexion. Association analysis (Pearson's chi-square and Cramér's V tests) was then performed to identify the SIM misalignments associated with LBP. Effect size was analyzed based on Hedges' g. The most common thoracic SIMs in CAA were total hyperkyphosis (male = 59.02%; female = 42.42%) and static hyperkyphosis (male = 11.48%; female = 6.06%). Hyperlordotic attitude (female = 30.30%; male = 4.92%), static-functional hyperkyphosis (male = 16.39%; female = 3.03%), and structured hyperlordosis (female = 21.21%; male = 1.64%) were the most common lumbar SIMs. Hyperlordotic attitude, static functional lumbar hyperkyphosis, and structured hyperlordosis were associated with LBP in male and female athletes.

The Potential Role of Hamstring Extensibility on Sagittal Pelvic Tilt, Sagittal Spinal Curves and Recurrent Low Back Pain in Team Sports Players: A Gender Perspective Analysis.

It is assumed that mechanical restriction of hamstring tightness disrupts sagittal spine-pelvis-leg alignment and alters the lumbar-pelvic rhythm predisposing to low back pain (LBP) in athletes; however, this association is not clear. A prospective cross-sectional cohort study was conducted to determine the influence of hamstring extensibility (HE) on sagittal pelvic tilt, sagittal spinal curves, and LBP in 94 soccer and basketball players (61 man and 33 woman) with (n = 36) and without recurrent LBP (n = 58). Descriptive analysis displayed significant gender differences for HE, sagittal pelvic tilt, and lumbar curve. Differences were found between the low-HE and high-HE groups in lumbosacral angle in for the maximum trunk forward flexion (LH-MTFP). Low-HE was associated with LH-MTFP, lumbar curve and LBP in male players (p ≤ 0.023). In female players, LH-MTFP and lumbar curve were associated with low-HE (p ≤ 0.020). Low-HE predicted LH-MTFP (p = 0.000; OR = 65.6950) and LBP (p = 0.028; OR = 13.915) in male players. The decision tree analysis showed that 50.8% of the players were classified with restricted LH-MTFP, 77.4% with low-HE among male players. The 100% of male players with recurrent LBP had low-HE. The 65% of female players with low-HE had restricted LH-MTFP. Measurement of HE, lumbar curve, and LH-MTFP are important in making training decisions for to reduce the incidence of recurrent LBP in soccer and basketball players.

Sagittal Integral Morphotype of Female Classical Ballet Dancers and Predictors of Sciatica and Low Back Pain.

The aims of this study were to describe the sagittal integral morphotype (SIM) of classical ballet (CB) dancers, and to establish predictor factors and their cut off values for high risk of experiencing sciatica or low back pain (LBP). This retrospective cohort study was performed in 33 female professional CB dancers. Data related to anthropometric parameters, CB dance experience, sciatica or LBP history, and sagittal spine curvatures were collected. A binary logistic regression and receiver-operating characteristic analysis were performed. The main spine misalignments observed in the SIM of CB dancers were thoracic functional hyperkyphosis, hypomobile kyphosis, and hypokyphosis, and those for the lumbar curvature were hyperlordotic attitude and functional hyperkyphosis. The lumbar curvature in slump sitting and trunk forward bending positions, together with the stature, were significant predictor factors of sciatica history, while the years of dance experience was a significant predictor factor of LBP history. The cut off values analysis revealed that dancers with a stature of 161 cm or less, and those with 14 years of experience or more, have a greater probability of experiencing sciatica or LBP history, respectively.

Coronal and axial alignment relationship in Caucasian patients with osteoarthritis of the knee.

Individualized pre-operative assessment of the patterns of the lower extremity anatomy and deformities in patients undergoing total knee arthroplasty seems essential for a successful surgery. In the present study, we investigated the relationship among the coronal alignment and the rotational profile of the lower extremities in the Caucasian population with end-stage knee osteoarthritis. We conducted a prospective study of 385 knees that underwent a pre-operative three-dimensional computed tomography-based model. The lower extremity alignment was determined (mechanical tibiofemoral or hip-knee-ankle angle, supplementary angle of the femoral lateral distal angle, and proximal medial tibial angle). For each case, the femoral distal rotation (condylar twist angle), the femoral proximal version, and the tibial torsion were determined. As the coronal alignment changed from varus to valgus, the femoral external rotation increased (r = 0.217; p < 0.0005). As the coronal alignment changed from varus to valgus, the external tibial torsion increased (r = 0.248; p < 0.0005). No correlation was found between the global coronal alignment and the femoral version. The present study demonstrates a linear relationship between the coronal alignment and the rotational geometry of the distal femur. This correlation also occurs with the tibial torsion. Perhaps outcomes of total knee arthroplasty surgery might be improved by addressing these deformities as well.

'Absolute' inter-observer classifications agreement for proximal humeral fractures with a single shoulder anteroposterior X-ray.

PURPOSE: Several studies have been carried out, and there is no classification for proximal humeral fractures (PHF) exempted from variability in interpretation and with questioned reliability. In the present study, we investigated the 'absolute diagnostic reliability' of the most currently used classifications for PHFs on a single anterior-posterior X-ray shoulder image. METHODS: Six orthopaedic surgeons, with varying levels of experience in shoulder pathology, evaluated radiographs from 30 proximal humeral fractures, according to the 'absolute reliability' criteria. Each of the observers rated each fracture according to Neer, Müller/AO and Codman-Hertel's classification systems. RESULTS: The overall inter-observer agreement (κ) has been 0.297 (CI95% 0.280 to 0.314) for the Neer's classification system, 0.206 (CI95% 0.193 to 0.218) for the Müller/AO classification system, and 0.315 (CI95% 0.334 to 0.368) for the Codman-Hertel classification system. We found loss of agreement in Neer's classification as the study progressed, low agreement in the AO classification, and stable values in the different evaluations with the best degree of agreement for Codman-Hertel classification, with a moderate agreement in the second evaluation among the six evaluators. CONCLUSION: The Neer, AO, and Hertel-Codman classification systems for PHF with a single radiographic projection have a difficult interpretation for orthopaedic surgeons of varying levels of experience, and therefore substantial agreements are not obtained.

Patient-Specific Instrumentation Accuracy Evaluated with 3D Virtual Models.

There have been remarkable advances in knee replacement surgery over the last few decades. One of the concerns continues to be the accuracy in achieving the desired alignment. Patient-specific instrumentation (PSI) was developed to increase component placement accuracy, but the available evidence is not conclusive. Our study aimed to determine a PSI system's three-dimensional accuracy on 3D virtual models obtained by post-operative computed tomography. We compared the angular placement values of 35 total knee arthroplasties (TKAs) operated within a year obtained with the planned ones, and we analyzed the possible relationships between alignment and patient-reported outcomes. The mean (SD) discrepancies measured by two experienced engineers to the planned values observed were 1.64° (1.3°) for the hip-knee-ankle angle, 1.45° (1.06°) for the supplementary angle of the femoral lateral distal angle, 1.44° (0.97°) for the proximal medial tibial angle, 2.28° (1.78°) for tibial slope, 0.64° (1.09°) for femoral sagittal flexion, and 1.42° (1.06°) for femoral rotation. Neither variables related to post-operative alignment nor the proportion of change between pre-and post-operative alignment influenced the patient-reported outcomes. The evaluated PSI system's three-dimensional alignment analysis showed a statistically significant difference between the angular values planned and those obtained. However, we did not find a relevant effect size, and this slight discrepancy did not impact the clinical outcome.

Developing of a Mathematical Model to Perform Measurements of Axial Vertebral Rotation on Computer-Aided and Automated Diagnosis Systems, Using Raimondi's Method.

INTRODUCTION: Axial vertebral rotation (AVR) is a basic parameter in the study of idiopathic scoliosis and on physical two-dimensional images. Raimondi's tables are the most used method in the quantification of AVR. The development of computing technologies has enabled the creation of computer-aided or automated diagnosis systems (CADx) with which measurement on medical images can be carried out more quickly, simply, and with less intra and interobserver variabilities than manual methods. Although there are several publications dealing with the measurement of AVR in CADx systems, none of them provides information on the equation or algorithm used for the measurement applying Raimondi's method. Goal. The aim of this work is to perform a mathematical modelling of the data contained in Raimondi's tables that enable the Raimondi method to be used in digital medical images more precisely and in a more exact manner. METHODS: Data from Raimondi's tables were tabulated on a first step. After this, each column of Raimondi's tables containing values corresponding to vertebral body width (D) were adjusted to a curve determined by AVR = f (d). Third, representative values of each rotation divided by D were obtained through the equation of each column D. In a fourth step, a regression line was fitted to the data in each row, and from its equation, the mean value of the D/d distribution is calculated (value corresponding to the central column, D = 45). Finally, a curve was adjusted to the obtained data using the least squares method. Summary and Conclusion. Our mathematical equation allows the Raimondi method to be used in digital images of any format in a more accurate and simplified approach. This equation can be easily and freely implemented in any CADx system to quantify AVR, providing a more precise use of Raimondi's method, as well as being used in traditional manual measurement as it is performed with Raimondi tables.

Impact of surgical instrumentation on hospital length of stay and cost of total knee arthroplasty.

BACKGROUND: We aimed to analyze the impact of two different types of surgical instrumentation (conventional manual instrumentation (CI) and patient-specific instrumentation (PSI)) on length of stay (LOS) and objectify differences in cost. We hypothesized that there are no differences in the LOS and cost due to the instrumentation system used. RESEARCH DESIGN AND METHODS: LOS was registered using inpatient admission data provided by the Institutional Management Control Department. We recorded the costs associated with each procedure that could be influenced by the use of one system or another during the in-hospital stay. We conducted a prospectively single-center cohort study of 305 TKAs. Surgery was performed with conventional CI in 122 cases and with PSI in 183 cases. RESULTS: The mean LOS for the CI group was 4.29 days (SD 1.65) and 4.22 days (SD 1.26), for the PSI group. No significant difference among both instrumentation systems was obtained. When comparing global costs, the mean cost was slightly higher (without a significant difference) for the PSI cases (€3110.24 vs. €2852.7 for the CI cases). CONCLUSIONS: LOS and overall cost, in hospitals with a low annual TKA surgery volume, are unrelated to conventional or patient-specific instrumentation.