Assessment of dynamic balance during walking in patients with adult spinal deformity.

PURPOSE: To assess dynamic postural alignment in ASD during walking using a subject-specific 3D approach. METHODS: 69 ASD (51 ± 20 years, 77%F) and 62 controls (34 ± 13 years, 62%F) underwent gait analysis along with full-body biplanar Xrays and filled HRQoL questionnaires. Spinopelvic and postural parameters were computed from 3D skeletal reconstructions, including radiographic odontoid to hip axis angle (ODHA) that evaluates the head's position over the pelvis (rODHA), in addition to rSVA and rPT. The 3D bones were then registered on each gait frame to compute the dynamic ODHA (dODHA), dSVA, and dPT. Patients with high dODHA (> mean + 1SD in controls) were classified as ASD-DU (dynamically unbalanced), otherwise as ASD-DB (dynamically balanced). Between-group comparisons and relationship between parameters were investigated. RESULTS: 26 patients were classified as ASD-DU having an average dODHA of 10.4° (ASD-DB: 1.2°, controls: 1.7°), dSVA of 112 mm (ASD-DB: 57 mm, controls: 43 mm), and dPT of 21° (ASD-DB: 18°, controls: 14°; all p < 0.001). On static radiographs, ASD-DU group showed more severe sagittal malalignment than ASD-DB, with more altered HRQoL outcomes. The ASD-DU group had an overall abnormal walking compared to ASD-DB & controls (gait deviation index: 81 versus 93 & 97 resp., p < 0.001) showing a reduced flexion/extension range of motion at the hips and knees with a slower gait speed and shorter step length. Dynamic ODHA was correlated to HRQoL scores. CONCLUSION: Dynamically unbalanced ASD had postural malalignment that persist during walking, associated with kinematic alterations in the trunk, pelvis, and lower limbs, making them more prone to falls. Dynamic-ODHA correlates better with HRQoL outcomes than dSVA and dPT.

Assessment of Patient Outcomes and Proximal Junctional Failure Rate of Patients with Adult Spinal Deformity Undergoing Caudal Extension of Previous Spinal Fusion.

OBJECTIVE: This case series examined patients undergoing caudal extension of prior fusion without alteration of the prior upper instrumented vertebra (UIV) to assess patient outcomes and rates of proximal junctional kyphosis (PJK)/proximal junctional failure (PJF). METHODS: Patients eligible for 2-year minimum follow-up undergoing caudal extension of prior fusion with unchanged UIVs were identified. These patients were evaluated for PJK/PJF, and patient reported outcomes were recorded. RESULTS: In total, 40 patients were included. Mean follow-up duration was 2.2 ± 0.3 years. Patients in this cohort had poor preoperative sagittal alignment (pelvic incidence minus lumbar lordosis [PI-LL] 26.7°, T1 pelvic angle [TPA] 29.0°, sagittal vertical axis [SVA] 93.4 mm) and achieved substantial sagittal correction (ΔSVA -62.2 mm, ΔPI-LL -19.8°, ΔTPA -11.1°) after caudal extension surgery. At final follow-up, there was a 0% rate of PJF among patients undergoing caudal extension of previous fusion without creation of a new UIV, but 27.5% of patients experienced PJK. Patients experienced significant improvement in both the Oswestry Disability Index and Scoliosis Research Society-22r total score at 2 years postoperatively (P < 0.05). In total, 7.5% (n = 3) of patients underwent further revision, at an average of 1.1 ± 0.54 years after the surgery with unaltered UIV. All 3 of these patients underwent revision for rod fracture with no revisions for PJK/PJF. CONCLUSIONS: Patients undergoing caudal extension of previous fusions for sagittal alignment correction have high rates of clinical success, low revision surgery rates, and very low rates of PJF. Minimizing repetitive tissue trauma at the UIV may result in decreased PJF risk because the PJF rate in this cohort of patients with unaltered UIV is below historical PJF rates of patients undergoing sagittal balance correction.

Toxicity Assessment of 4 Azo Dyes in Zebrafish Embryos.

Azo dyes are used widely as color additives in food, drugs, and cosmetics; hence, there is an increasing concern about their safety and possible health hazards. In the present study, we chose 4 azo dyes tartrazine, Sunset Yellow, amaranth, and Allura red and evaluated their developmental toxicity on zebrafish embryos. At concentration levels of 5 to 50 mM, we found that azo dyes can induce hatching difficulty and developmental abnormalities such as cardiac edema, decreased heart rate, yolk sac edema, and spinal defects including spinal curvature and tail distortion. Exposure to 100 mM of each azo dye was completely embryolethal. The median lethal concentration (LC50), median effective concentration (EC50), and teratogenic index (TI) were calculated for each azo dye at 72 hours postfertilization. For tartrazine, the LC50 was 47.10 mM and EC50 value was at 42.66 mM with TI ratio of 1.10. For Sunset Yellow, the LC50 was 38.93 mM and EC50 value was at 29.81 mM with TI ratio of 1.31. For amaranth, the LC50 was 39.86 mM and EC50 value was at 31.94 mM with TI ratio of 1.25. For Allura red, the LC50 was 47.42 mM and EC50 value was 40.05 mM with TI ratio of 1.18. This study reports the developmental toxicity of azo dyes in zebrafish embryos at concentrations higher than the expected human exposures from consuming food and drugs containing azo dyes.

Comparative effectiveness of imaging modalities for preoperative assessment of anorectal malformation in the pediatric population.

OBJECTIVE: The aim of this study was to compare the accuracy of MRI, colostography/fistulography, and X-ray imaging modalities for preoperative diagnosis of anorectal malformations (ARMs) in pediatric patients. METHODS: This retrospective analysis included a total of 84 pediatric patients with ARMs. Preoperative imaging findings were assessed by 2 radiologists and compared to surgical findings. RESULTS: MRI identified anomalies of the spine in 25 of 84 patients (29.8%), anomalies of the genital system in 7 of 84 patients (8.3%), anomalies of the urinary system in 22 of 84 patients (26.2%), and underdeveloped sphincter muscle complex in 34 of 84 patients (40.5%). In the 44 subjects receiving both MRI and X-ray, MRI was more sensitive in detecting anomalies of spine (18/44 vs. 8/44; P = 0.002), and both correctly identified the distal end of the rectum in 77.3% (34/44) of the cases. In the 24 subjects receiving both MRI and colostography/fistulography, MRI was more accurate in identifying Pena's classification (22/24 vs. 15/24; P = 0.039). Distal end of the rectum was correctly identified in 75.0% (18/24) and 58.3% (14/24) of the cases (P = 0.125). CONCLUSIONS: MRI could clearly reveal fistula anatomy and associated anomalies of ARMs and should be routinely used for preoperative evaluation of ARMs. TYPE OF STUDY: Study of diagnostic test. LEVEL OF EVIDENCE: Level II.

The Dubousset Functional Test is a Novel Assessment of Physical Function and Balance.

BACKGROUND: Currently, the functional status of patients undergoing spine surgery is assessed with quality-of-life questionnaires, and a more objective and quantifiable assessment method is lacking. Dr. Jean Dubousset conceptually proposed a four-component functional test, but to our knowledge, reference values derived from asymptomatic individuals have not yet been reported, and these are needed to assess the test's clinical utility in patients with spinal deformities. QUESTIONS/PURPOSES: (1) What are the reference values for the Dubousset Functional Test (DFT) in asymptomatic people? (2) Is there a correlation between demographic variables such as age and BMI and performance of the DFT among asymptomatic people? METHODS: This single-institution prospective study was performed from January 1, 2018 to May 31, 2018. Asymptomatic volunteers were recruited from our college of medicine and hospital staff to participate in the DFT. Included participants did not report any musculoskeletal problems or trauma within 5 years. Additionally, they did not report any history of lower limb fracture, THA, TKA, or patellofemoral arthroplasty. Patients were also excluded if they reported any active medical comorbidities. Demographic data collected included age, sex, BMI, and self-reported race. Sixty-five asymptomatic volunteers were included in this study. Their mean age was 42 ± 15 years; 27 of the 65 participants (42%) were women. Their mean BMI was 26 ± 5 kg/m. The racial distribution of the participants was 34% white (22 of 65 participants), 25% black (16 of 65 participants), 15% Asian (10 of 65 participants), 9% subcontinental Indian (six of 65 participants), 6% Latino (four of 65 participants), and 10% other (seven of 65 participants). In a controlled setting, participants completed the DFT after verbal instruction and demonstration of each test, and all participants were video recorded. The four test components included the Up and Walking Test (unassisted sit-to-stand from a chair, walk forward/backward 5 meters [no turn], then unassisted stand-to-sit), Steps Test (ascend three steps, turn, descend three steps), Down and Sitting Test (stand-to-ground, followed by ground-to-stand, with assistance as needed), and Dual-Tasking Test (walk 5 meters forwards and back while counting down from 50 by 2). Tests were timed, and data were collected from video recordings to ensure consistency. Reference values for the DFT were determined via a descriptive analysis, and we calculated the mean, SD, 95% CI, median, and range of time taken to complete each test component, with univariate comparisons between men and women for each component. Linear correlations between age and BMI and test components were studied, and the frequency of verbal and physical pausing and adverse events was noted. RESULTS: The Up and Walking Test was completed in a mean of 15 seconds (95% CI, 14-16), the Steps Test was completed in 6.3 seconds (95% CI, 6.0-6.6), the Down and Sitting Test was completed in 6.0 seconds (95% CI, 5.4-6.6), and the Dual-Tasking Test was performed in 13 seconds (95% CI, 12-14). The length of time it took to complete the Down and Sitting (r = 0.529; p = 0.001), Up and Walking (r = 0.429; p = 0.001), and Steps (r = 0.356; p = 0.014) components increased with as the volunteer's age increased. No correlation was found between age and the time taken to complete the Dual-Tasking Test (r = 0.134; p = 0.289). Similarly, the length of time it took to complete the Down and Sitting (r = 0.372; p = 0.005), Up and Walking (r = 0.289; p = 0.032), and Steps (r = 0.366; p = 0.013) components increased with increasing BMI; no correlation was found between the Dual-Tasking Test's time and BMI (r = 0.078; p = 0.539). CONCLUSIONS: We found that the DFT could be completed by asymptomatic volunteers in approximately 1 minute, although it took longer for older patients and patients with higher BMI. CLINICAL RELEVANCE: We believe, but did not show, that the DFT might be useful in assessing patients with spinal deformities. The normal values we calculated should be compared in future studies with those of patients before and after undergoing spine surgery to determine whether this test has practical clinical utility. The DFT provides objective metrics to assess function and balance that are easy to obtain, and the test requires no special equipment.

Improving Complex Pediatric and Adult Spine Care While Embracing the Value Equation.

INTRODUCTION: Value in health care is defined as the quotient of outcomes to cost. Both pediatric and adult spinal deformity surgeries are among the most expensive procedures offered today. With high variability in both outcomes and costs in spine surgery today, surgeons will be expected to consider long-term cost effectiveness when comparing treatment options. METHODS: We summarize various methods by which value can be increased in complex spine surgery, both through the improvement of outcomes and the reduction of cost. These methods center around standardization, team-based and collaborative approaches, rigorous outcomes tracking through dashboards and registries, and continuous process improvement. RESULTS: This manuscript reviews the expert opinion of leading spine specialists on the improvement of safety, quality and improvement of value of pediatric and adult spinal surgery. CONCLUSION: Without surgeon leadership in this arena, suboptimal solutions may result from the isolated intervention of regulatory bodies or payer groups. The cooperative development of standardized, team-based approaches in complex spine surgery will lead to the high-quality, high-value care for patients.

Two Surgeon Approach for Complex Spine Surgery: Rationale, Outcome, Expectations, and the Case for Payment Reform.

There is an increased trend in complex spine deformity cases toward a two attending surgeon approach, but the practice has not become widely accepted by payers. Multiple studies have shown that spine surgery complications increase with the duration of case, estimated blood loss, and use of transfusions, as well as in certain high-risk populations or those requiring three-column osteotomies. Dual-surgeon cases have been shown to decrease estimated blood loss, transfusion rate, surgical times, and therefore complication rates. Although this practice comes at an uncertain price to medical training and short-term costs, the patient's quality of care should be prioritized by institutions and payers to include dual-surgeon coverage for these high-risk cases. Because we enter an era where the value of spine care and demonstrating cost-effectiveness is essential, dual surgeon attending approaches can enhance these tenets.

Building Consensus: Development of Best Practice Guidelines on Wrong Level Surgery in Spinal Deformity.

STUDY DESIGN: Consensus-building using the Delphi and nominal group technique. OBJECTIVE: To establish best practice guidelines using formal techniques of consensus building among a group of experienced spinal deformity surgeons to avert wrong-level spinal deformity surgery. SUMMARY OF BACKGROUND DATA: Numerous previous studies have demonstrated that wrong-level spinal deformity occurs at a substantial rate, with more than half of all spine surgeons reporting direct or indirect experience operating on the wrong levels. Nevertheless, currently, guidelines to avert wrong-level spinal deformity surgery have not been developed. METHODS: The Delphi process and nominal group technique were used to formally derive consensus among 16 fellowship-trained spine surgeons. Surgeons were surveyed for current practices, presented with the results of a systematic review, and asked to vote anonymously for or against item inclusion during three iterative rounds. Agreement of 80% or higher was considered consensus. Items near consensus (70% to 80% agreement) were probed in detail using the nominal group technique in a facilitated group meeting. RESULTS: Participants had a mean of 13.4 years of practice (range: 2-32 years) and 103.1 (range: 50-250) annual spinal deformity surgeries, with a combined total of 24,200 procedures. Consensus was reached for the creation of best practice guidelines (BPGs) consisting of 17 interventions to avert wrong-level surgery. A final checklist consisting of preoperative and intraoperative methods, including standardized vertebral-level counting and optimal imaging criteria, was supported by 100% of participants. CONCLUSION: We developed consensus-based best practice guidelines for the prevention of wrong-vertebral-level surgery. This can serve as a tool to reduce the variability in preoperative and intraoperative practices and guide research regarding the effectiveness of such interventions on the incidence of wrong-level surgery. LEVEL OF EVIDENCE: Level V.

Radiopaque UHMWPE sublaminar cables for spinal deformity correction: Preclinical mechanical and radiopacifier leaching assessment.

Polymeric sublaminar cables have a number of advantages over metal cables in the field of spinal deformity surgery, with decreased risk of neurological injury and potential for higher correction forces as the two most predominant. However, currently available polymer cables are radiolucent, precluding postoperative radiological assessment of instrumentation stability and integrity. This study provides a preclinical assessment of a woven UHMWPE cable made with radiopaque UHMWPE fibers. Our primary goal was to determine if the addition of a radiopacifier negatively affects the mechanical properties of UHMWPE woven cables. Tensile mechanical properties were determined and compared to suitable controls. Radiopacity was evaluated and radiopacifier leaching was assessed in vitro and in vivo. Finally, in vivo bismuth organ content was quantified after a 24-week implantation period in sheep. Results show that the mechanical properties of woven UHMWPE cables were not deleteriously affected by the addition of homogenously dispersed bismuth oxide particles within each fiber. Limited amounts of bismuth oxide were released in vitro, well below the toxicological threshold. Tissue concentrations lower than generally accepted therapeutic dosages for use against gastrointestinal disorders, well below toxic levels, were discovered in vivo. These results substantiate controlled clinical introduction of these radiopaque UHMWPE cables. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 771-779, 2018.

Community Care Administration of Spinal Deformities in the Brazilian Public Health System.

OBJECTIVE:: Underfunding of the surgical treatment of complex spinal deformities has been an important reason for the steadily growing waiting lists in publicly funded healthcare systems. The aim of this study is to characterize the management of the treatment of spinal deformities in the public healthcare system. METHODS:: A cross-sectional study of 60 patients with complex pediatric spinal deformities waiting for treatment in December 2013 was performed. The evaluated parameters were place of origin, waiting time until first assessment at a specialized spine care center, waiting time for the surgical treatment, and need for implants not reimbursed by the healthcare system. RESULTS:: Ninety-one percent of the patients lived in São Paulo State (33% from Ribeirão Preto - DRS XIII). Patients waited for 0.5 to 48.0 months for referral, and the waiting times for surgery ranged from 2 to 117 months. Forty-five percent of the patients required implants for the surgical procedure that were not available. CONCLUSION:: The current management of patients with spinal deformities in the public healthcare system does not provide adequate treatment for these patients in our region. They experience long waiting periods for referral and prolonged waiting times to receive surgical treatment; additionally, many of the necessary procedures are not reimbursed by the public healthcare system.

Community Care Administration of Spinal Deformities in the Brazilian Public Health System

OBJECTIVE: Underfunding of the surgical treatment of complex spinal deformities has been an important reason for the steadily growing waiting lists in publicly funded healthcare systems. The aim of this study is to characterize the management of the treatment of spinal deformities in the public healthcare system. METHODS: A cross-sectional study of 60 patients with complex pediatric spinal deformities waiting for treatment in December 2013 was performed. The evaluated parameters were place of origin, waiting time until first assessment at a specialized spine care center, waiting time for the surgical treatment, and need for implants not reimbursed by the healthcare system. RESULTS: Ninety-one percent of the patients lived in São Paulo State (33% from Ribeirão Preto - DRS XIII). Patients waited for 0.5 to 48.0 months for referral, and the waiting times for surgery ranged from 2 to 117 months. Forty-five percent of the patients required implants for the surgical procedure that were not available. CONCLUSION: The current management of patients with spinal deformities in the public healthcare system does not provide adequate treatment for these patients in our region. They experience long waiting periods for referral and prolonged waiting times to receive surgical treatment; additionally, many of the necessary procedures are not reimbursed by the public healthcare system.

Assessment of the Cross-Sectional Areas of the Psoas Major and Multifidus Muscles in Patients With Adult Spinal Deformity: A Case-Control Study.

STUDY DESIGN: This is a case-control study. OBJECTIVE: The present study aimed to compare the cross-sectional areas of the psoas major and multifidus muscles between elderly patients with adult spinal deformity (ASD) and age-matched and body weight-matched controls, and to evaluate the associations between the cross-sectional areas of these muscles and the severity of spinal deformity. SUMMARY OF BACKGROUND DATA: The study included 49 female kyphosis patients with mild scoliosis (Cobb angle <20 degrees; mean age, 70.9 y, group D). The control group (group C) included age-matched and body weight-matched female patients who underwent abdominal surgery (n=98; mean age, 71.7 y). MATERIALS AND METHODS: The cross-sectional areas of the bilateral psoas majors and multifidus muscles were calculated using preoperative L4/L5 axial computed tomography images. In group D, the following spinopelvic parameters were assessed: sagittal vertical axis, pelvic tilt, pelvic incidence, lumbar lordosis, and thoracic kyphosis. The relationships between the muscle cross-sectional areas and spinopelvic parameters were evaluated. RESULTS: The cross-sectional area of the multifidus muscle was lower in group D than in group C. However, the cross-sectional area of the psoas major muscle was not different between the 2 groups. In multiple regression analysis, the cross-sectional area of the multifidus muscle was significantly associated with all spinopelvic parameters. CONCLUSIONS: The cross-sectional area of the multifidus muscle might be lower in elderly patients with ASD than in controls. In the elderly population, the severity of sagittal spinal deformity might be correlated with the cross-sectional area of the multifidus muscle. Therefore, muscle imbalances between the flexors and extensors of the spine could participate in the pathology of ASD.

Cell Saver for Adult Spinal Deformity Surgery Reduces Cost.

STUDY DESIGN: Retrospective cohort. OBJECTIVES: To determine if the use of cell saver reduces overall blood costs in adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: Recent studies have questioned the clinical value of cell saver during spine procedures. METHODS: ASD patients enrolled in a prospective, multicenter surgical database who had complete preoperative and surgical data were identified. Patients were stratified into (1) cell saver available during surgery, but no intraoperative autologous infusion (No Infusion group), or (2) cell saver available and received autologous infusion (Infusion group). RESULTS: There were 427 patients in the Infusion group and 153 in the No infusion group. Patients in both groups had similar demographics. Mean autologous infusion volume was 698 mL. The Infusion group had a higher percentage of EBL relative to the estimated blood volume (42.2%) than the No Infusion group (19.6%, p < .000). Allogeneic transfusion was more common in the Infusion group (255/427, 60%) than the No Infusion group (67/153, 44%, p = .001). The number of allogeneic blood units transfused was also higher in the Infusion group (2.4) than the No Infusion group (1.7, p = .009). Total blood costs ranged from $396 to $2,146 in the No Infusion group and from $1,262 to $5,088 in the Infusion group. If the cost of cell saver blood was transformed into costs of allogeneic blood, total blood costs for the Infusion group would range from $840 to $5,418. Thus, cell saver use yielded a mean cost savings ranging from $330 to $422 (allogeneic blood averted). Linear regression showed that after an EBL of 614 mL, cell saver becomes cost-efficient. CONCLUSION: Compared to transfusing allogeneic blood, cell saver autologous infusion did not reduce the proportion or the volume of allogeneic transfusion for patients undergoing surgery for adult spinal deformity. The use of cell saver becomes cost-efficient above an EBL of 614 mL, producing a cost savings of $330 to $422. LEVEL OF EVIDENCE: Level III.

MICROCOMPUTED TOMOGRAPHIC, MORPHOMETRIC, AND HISTOPATHOLOGIC ASSESSMENT OF CONGENITAL BONE MALFORMATIONS IN TWO NEOTROPICAL VIPERIDS.

Congenital malformations have been reported in all classes of vertebrates and may be a determinant of life span and survival. In reptiles, the incidence of congenital malformations can be associated with genetic and environmental causes, including pollution. The characterization of pathological processes involved in the development of congenital malformations of bone in snakes is rare in the literature, but is of great relevance in the field of reptile conservation and environmental health. We describe congenital bone lesions in 50 newborn jararaca (Bothrops jararaca) and 26 South American rattlesnakes (Crotalus durissus terrificus) born from wild-caught pregnant females in Southeastern Brazil. Lesions were evaluated by morphometric quantitative analysis, x-ray microtomography, and histopathologic descriptive analysis. Morphometric analysis showed that jararaca presented more severe axial lesions (kyphosis, scoliosis, and kyphoscoliosis) than rattlesnakes. Female rattlesnakes presented more severe axial lesions than did males. In rattlesnakes, spinal deformities were more frequently diagnosed in the caudal segment of the body. We present x-ray microtomographic assessments and images of malformed snakes (n=9) and characterized novel malformations, such as the agenesis of frontal, parietal, and supraoccipital bones in a jararaca specimen. Histopathologic findings included vertebral body fusion, myositis, coagulation necrosis, and disorganization of periaxial muscle fibers. The new methods and results presented in this study will be useful and informative for future research in pathology, teratology, embryology, and ecotoxicology in snakes.

Low vertebral ano-rectal cardiac tracheo-esophageal renal limb screening rates in children with anorectal malformations.

BACKGROUND: The aim of this study was to establish the rate of screening for associated cardiac, vertebral, spinal cord, urologic, and limb anomalies vertebral ano-rectal cardiac tracheo-esophageal renal limb (VACTERL) in children with anorectal malformation (ARM). METHODS: We performed a retrospective cohort study using the Medicaid Analytic eXtract database which contains enrollment and utilization claims and demographic information from all Medicaid enrollees. Patients born between January 2005 and December 2008 with International Classification of Diseases, Ninth Revision codes for a diagnosis of ARM within 30 days of life, an ARM procedure code during the first year of life, and a minimum of 12 months of continuous enrollment were included. VACTERL screening was determined using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes for diagnostic tests used to detect these anomalies. RESULTS: A total of 406 patients were identified (231 males). Evaluation of the spinal vertebrae was performed in 94% of patients (381 of 406). Spinal cord evaluation was performed in 57% (231 of 406): 52% (121 of 231) received spinal ultrasound (US), 24% (56 of 231) received spinal magnetic resonance imaging, and 23% (54 of 231) received both. Sacral radiographs were performed in 8% (32 of 406) and 77% (313 of 406) underwent an echocardiogram. Genitourinary evaluation was performed in 84% (341 of 406): 67% (229 of 341) received renal US, 8% (27 of 341) received abdominal US, and 25% (85 of 341) received both. Limb evaluation was recorded in 19% (76 of 406). Multiple screening including an echocardiogram, spinal radiograph, spinal cord evaluation, and renal evaluation was performed in 45% (181 of 406); 2% (7 of 406) did not receive any screening tests. CONCLUSIONS: Low VACTERL screening in children with ARM suggests that associated anomalies may be undiagnosed which may lead to increased long-term morbidity.

Skeletal anomaly assessment in diploid and triploid juvenile Atlantic salmon (Salmo salar L.) and the effect of temperature in freshwater.

Triploid Atlantic salmon tend to develop a higher prevalence of skeletal anomalies. This tendency may be exacerbated by an inadequate rearing temperature. Early juvenile all-female diploid and triploid Atlantic salmon were screened for skeletal anomalies in consecutive experiments to include two size ranges: the first tested the effect of ploidy (0.2-8 g) and the second the effect of ploidy, temperature (14 °C and 18 °C) and their interaction (8-60 g). The first experiment showed that ploidy had no effect on skeletal anomaly prevalence. A high prevalence of opercular shortening was observed (average prevalence in both ploidies 85.8%) and short lower jaws were common (highest prevalence observed 11.3%). In the second experiment, ploidy, but not temperature, affected the prevalence of short lower jaw (diploids > triploids) and lower jaw deformity (triploids > diploids, highest prevalence observed 11.1% triploids and 2.7% diploids) with a trend indicating a possible developmental link between the two jaw anomalies in triploids. A radiological assessment (n = 240 individuals) showed that at both temperatures triploids had a significantly (P < 0.05) lower number of vertebrae and higher prevalence of deformed individuals. These findings (second experiment) suggest ploidy was more influential than temperature in this study.

[Sagittal Balance of the Spine--Clinical Importance and Radiographic Assessment]. / Die sagittale Wirbelsäulenbalance--klinische Bedeutung und radiologische Bemessung.

Sagittal deformities of the spine frequently result in back pain, as patients have to expend much energy in compensation. The sagittal alignment of the spine is defined by its curvatures (lordosis and kyphosis) relative to the position of the pelvis. Diagnostic assessment is based on full spine a. p. and lateral X-rays. The sagittal balance is primarily described by different angles that can be measured, e.g. lumbar lordosis, pelvic incidence, pelvic tilt and thoracic kyphosis. The quality of life can best be estimated by subtracting lumbar lordosis from the pelvic incidence. However, initial evaluation of the sagittal balance can also be based on the sagittal vertical axis. The severity of imbalance can be described by the sagittal vertical axis and the pelvic tilt, but surgical therapy necessitates a more profound analysis, which can be based on the SRS-Schwab classification.