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Study design: Survey. Objectives: Bracing is the mainstay of conservative treatment in Adolescent Idiopathic Scoliosis (AIS). The purpose of this study was to establish best practice guidelines (BPG) among a multidisciplinary group of international bracing experts including surgeons, physiatrists, physical therapists, and orthotists utilizing formal consensus building techniques. Summary of background data: Currently, there is significant variability in the practice of brace treatment for AIS and, therefore, there is a strong need to develop BPG for bracing in AIS. Methods: We utilized the Delphi process and the nominal group technique to establish consensus among a multidisciplinary group of bracing experts. Our previous work identified areas of variability in brace treatment that we targeted for consensus. Following a review of the literature, three iterative surveys were administered. Topics included bracing goals, indications for starting and discontinuing bracing, brace types, brace prescription, radiographs, physical activities, and physiotherapeutic scoliosis-specific exercises. A face-to-face meeting was then conducted that allowed participants to vote for or against inclusion of each item. Agreement of 80% throughout the surveys and face-to-face meeting was considered consensus. Items that did not reach consensus were discussed and revised and repeat voting for consensus was performed. Results: Of the 38 experts invited to participate, we received responses from 32, 35, and 34 for each survey, respectively. 11 surgeons, 4 physiatrists, 8 physical therapists, 3 orthotists, and 1 research scientist participated in the final face-to-face meeting. Experts reached consensus on 67 items across 10 domains of bracing which were consolidated into the final best practice recommendations. Conclusions: We believe that adherence to these BPG will lead to fewer sub-optimal outcomes in patients with AIS by reducing the variability in AIS bracing practices, and provide a framework future research. Level of evidence: Level IV.

Cumulative trauma disorders are on the rise. But don't jump to conclusions--about carpal tunnel syndrome or any other disorder--without a meticulous review of symptoms and selective use of diagnostic tests. [...]

Legg-Calve-Perthes disease is a disease of children in which there is osteochondritis (inflammation of the cartilage) of the epiphysis of the upper femur (hip joint end of the thigh bone). In the growing child the epiphysis, or secondary bone-forming center, is separated from the thigh bone by cartilage. It is rare for the disease to recur after complete healing has occurred. A case is reported of a four-year-old girl diagnosed to have osteochondritis of the left hip and treated successfully by traction and a weight-bearing brace. Eight months later, during follow-up examination, X-rays documented osteochondritis of the right hip, without symptoms. Six months later the girl developed mild symptoms in the right hip (pain in the thigh, limited internal rotation of the thigh and flexion contracture). There was complete healing by the time the child was eight years four months. Over the next four years she was admitted to the hospital five times for hip pain and required traction to restore range of motion. Currently, she is 12 years old and has no pain, but has a gait deformity on the right side with severe restriction of hip motion on that side. The literature on recurrent Legg-Calve-Perthes disease is reviewed; there were five previously reported cases. In all cases the age of onset of the disease ranged from two to six years; all recurrences involved the entire femoral head. Five patients were boys. Since the patients were older at the time of recurrence, their prognoses were less favorable. Recurrence of Legg-Calve-Perthes disease supports the hypothesis that multiple vascular infarctions (tissue death due to inadequate blood supply to the area) may cause the disease. (Consumer Summary produced by Reliance Medical Information, Inc.)

The capital femoral epiphysis is the head of the femur (thigh bone) at the hip joint. Until growth is completed the epiphysis is separated from the shaft of the femur by the cartilaginous growth plate. A slipped capital femoral epiphysis occurs when there is a disruption through this plate. This condition results in dysfunction of hip movements and may lead to the development of osteoarthrosis. Treatment is aimed at avoiding osteoarthrosis by preventing further displacement. A retrospective review was undertaken of 124 patients (155 hips) an average of 41 years after symptoms began. Contact was made with 82 of these patients; 41 were personally evaluated and the others completed a questionnaire. Information on the patients unable to be contacted was taken from the records of their most recent follow-up. Patients had been treated at the average age of 13 (range 8 to 18 years), and initial symptoms included hip pain (55 percent), thigh or knee pain (13 percent), or limp (5 percent). Twelve patients were without symptoms. Forty-two of the slips were considered mild, 32 percent moderate and 26 percent severe. Thirty-nine hips were treated with reduction, and 65 with realignment. Of the patients with chronic slipped epiphysis, 25 percent were treated symptomatically, 30 percent with spica cast (from the lower torso to the legs), and 24 percent with pinning the epiphysis in place. At follow-up both Iowa hip-rating and X-ray classification of degenerative disease were performed; these ratings were worse when slip was more severe and when reduction or realignment had been performed. Deterioration over time was most severe with the most severe slippage. It is concluded that realignment is associated with complications. The best treatment, regardless of severity of the slip, was in-situ pinning; this provided the best long-term function, delay of degenerative arthritis and had a low risk of complications. (Consumer Summary produced by Reliance Medical Information, Inc.)

EXPRESS STOP The history: Septic arthritis is a medical emergency requiring a targeted review of the current episode. Severe, acute, unremitting pain is typical of joint infection. The child is [...]

This study was designed to evaluate the Scoliometer[CR], an instrument that measures axial trunk rotation in individuals with scoliosis. The objectives included determining 1) the Scoliometer's[CR] screening capability and validity and 2) the intrarater and interrater reliability of Scoliometer[CR] measurements Scoltometer[CR] measurements made by two raters on 65 persons with idiopathic scoliosis were correlated with radiographic assessment of vertebral (pedicle) rotation and lateral curvature (Cobb method). Correlations ranged from .32 to . 46 with pedicle rotation and from 46 to .54 with the Cobb angle. Frequency analysis revealed relatively good specificity, sensitivity, and predictive capability of the Scoliometer[CR]. Intrarater and interrater reliability coefficients were high (r = .86-97) These results indicate good measurement reproducibility. The less-than-optimal betweenmethod correlation coefficients suggest that the validity of Scoliometer[CR] measurements is not sufficient to tue this method alone for determining patient diagnosis and management. Based on the positive-frequency analysis, however, the use of this tool as a screening device would be appropriate. [Amendt LE, Attse-Ellias KL, Eybers JL, et al: Validity and reliability testing of the Scoliometer[CR]. Phys Ther 70:108-117, 1990], The recent widespread use of school screening programs for the early detection of scoliosis has led to the development of various clinical methods to quantify scoliotic deformities. The forward-bend test [...]

The recently developed magnetically controlled growing rod (MCGR) system has gained popularity because it limits additional surgical lengthening procedures and promises reduction of the complication rate previously reported for the traditional growing rods. A retrospective single-center study was performed. Demographic and complications data were recorded. A statistical analysis was conducted to quantify the effect of MCGR placement and of subsequent lengthening on the Cobb angle, T1-T12 kyphosis, and the distances from T1-T12 and T1-S1. Twenty-four patients met the inclusion criteria. Six had idiopathic scoliosis and 18 patients had nonidiopathic scoliosis (neuromuscular and syndromic scoliosis). Nine patients underwent primary MCGR placement, and 15 had the traditional growing rods removed and replaced with MCGRs. The mean age at surgery and at last follow-up was 6.3 years and 8.8 years, respectively. The mean follow-up was 29.2 months. The MCGR placement significantly reduced the Cobb angle and kyphosis by an average of 21.33° and 10.79°, respectively. The T1-T12 and the T1-S1 distances increased an average of 1.19 and 1.89 cm/year, respectively, during the follow-up period. The average percentage of achieved-to-intended distraction was 65% on the concave side and 68% on the convex side at last follow-up. There were 9 postoperative complications in 8 (33%) patients, 6 of whom had nonidiopathic scoliosis. The MCGR system is reliable and effective in the treatment of patients affected by early-onset scoliosis. [The recently developed magnetically controlled growing rod (MCGR) system has gained popularity because it limits additional surgical lengthening procedures and promises reduction of the complication rate previously reported for the traditional growing rods. A retrospective single-center study was performed. Demographic and complications data were recorded. A statistical analysis was conducted to quantify the effect of MCGR placement and of subsequent lengthening on the Cobb angle, T1-T12 kyphosis, and the distances from T1-T12 and T1-S1. Twenty-four patients met the inclusion criteria. Six had idiopathic scoliosis and 18 patients had nonidiopathic scoliosis (neuromuscular and syndromic scoliosis). Nine patients underwent primary MCGR placement, and 15 had the traditional growing rods removed and replaced with MCGRs. The mean age at surgery and at last follow-up was 6.3 years and 8.8 years, respectively. The mean follow-up was 29.2 months. The MCGR placement significantly reduced the Cobb angle and kyphosis by an average of 21.33° and 10.79°, respectively. The T1-T12 and the T1-S1 distances increased an average of 1.19 and 1.89 cm/year, respectively, during the follow-up period. The average percentage of achieved-to-intended distraction was 65% on the concave side and 68% on the convex side at last follow-up. There were 9 postoperative complications in 8 (33%) patients, 6 of whom had nonidiopathic scoliosis. The MCGR system is reliable and effective in the treatment of patients affected by early-onset scoliosis. [Orthopedics. 2020;43(6):e601–e608.]

Study Design: Prognostic study and validation using prospective clinical trial data. Objective: To derive and validate a model predicting curve progression to =45° before skeletal maturity in untreated patients with adolescent idiopathic scoliosis (AIS). Summary of Background Data: Studies have linked the natural history of AIS with characteristics such as sex, skeletal maturity, curve magnitude, and pattern. The Simplified Skeletal Maturity Scoring System may be of particular prognostic utility for the study of curve progression. The reliability of the system has been addressed; however, its value as a prognostic marker for the outcomes of AIS has not. The BrAIST trial followed a sample of untreated AIS patients from enrollment to skeletal maturity, providing a rare source of prospective data for prognostic modeling. Methods: The development sample included 115 untreated BrAIST participants. Logistic regression was used to predict curve progression to =45° (or surgery) before skeletal maturity. Predictors included the Cobb angle, age, sex, curve type, triradiate cartilage, and skeletal maturity stage (SMS). Internal and external validity was evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n = 152). Indices of discrimination and calibration were estimated. A risk classification was created and the accuracy evaluated via the positive (PPV) and negative predictive values (NPV). Results: The final model included the SMS, Cobb angle, and curve type. The model demonstrated strong discrimination (c-statistics 0.89–0.91) and calibration in all data sets. The classification system resulted in PPVs of 0.71–0.72 and NPVs of 0.85–0.93. Conclusions: This study provides the first rigorously validated model predicting a short-term outcome of untreated AIS. The resultant estimates can serve two important functions: 1) setting benchmarks for comparative effectiveness studies and 2) most importantly, providing clinicians and families with individual risk estimates to guide treatment decisions. Level of Evidence: Level 1, prognostic.

This study describes a new procedure for a safer and easier access for the intrathecal injection of the recently approved nusinersen therapy in spinal muscular atrophy. This therapy changed the natural history of the disease, but, to date, scoliosis surgery was an excluding criteria for nusinersen therapy. The bone mass, due to the posterior spinal fusion of the scoliosis surgery, prevents the needle for the nusinersen administration from intervertebral access. This is a single-center, single-surgeon case series descriptive study. A laminotomy at the L3–L4 level was performed to provide safer access for the intrathecal injection. The procedure was carried out during the scoliosis surgery in patients who underwent posterior spinal fusion (PSF) after the nusinersen therapy was introduced, whereas for those who underwent PSF earlier, a second procedure was necessary to perform a laminotomy. A fat grafting was used to prevent bone overgrowth in the laminotomy. Markers were applied as radiographic references for the intrathecal injection. Five patients were enrolled, four females and one male. The mean age of the patients was 11 years. Three patients underwent PSF before the introduction of the nusinersen therapy. Two patients underwent PSF after the nusinersen therapy was available. All of them underwent a laminotomy with a fat grafting at the L3–L4 laminotomy level and received nusinersen therapy without complications. The procedure described is simple and effective in providing safe intrathecal access to make these patients eligible for such important therapy.

In 2018, the AAOS Board of Directors (BoD) approved the 2019-2023 Strategic Plan, which included the organization's mission: "Serving our profession to provide the highest quality musculoskeletal care." A board may use a continual SWOT (strengths, weaknesses, opportunities, threats) analysis of existing and potential programs and timing, as well as delegate operational responsibilities to board-designated committees or other entities, to stay ahead of emerging trends rather than trying to react or catch up to them. Operational agility requires fewer committees reporting directly to the Board, which is consistent with AAOS' Governance Principles that were adopted in 2018. [Extracted from the article]

With Americans living longer, many physicians and surgeons have extended their medical and surgical practice life beyond the traditional 65-year-old retirement age. As retirement is inevitable, planning for that eventuality, which in early practice years appears unnecessary, is in fact an exercise which will pay dividends at the time of retirement. Two senior orthopaedic surgeons provide insight on the 2 main issues concerning retirement: how to prepare for retirement while in active practice, and factors to consider as to the timing of that major life event.

We estimate a seismogeodetic earthquake moment magnitude using unclipped, broadband velocity and displacement waveforms from collocated Global Navigation Satellite Systems and seismic stations located within 800 km epicentral distance for nine 7.2 < Mw${M}_{w}$< 9.1 earthquakes. We consider the vertical component of seismogeodetic displacement as an approximate source time function and integrate the associated time series to obtain the seismic moment. By continuing to integrate vertical displacement beyond the initial P‐waves, we obtain rapid estimates of Mw${M}_{w}$that are within 0.2 magnitude units for 8 thrust faulting events and within 0.3 units for the single normal faulting event. Because our estimates of the seismic moment are based on the maximum value of integrated displacement, no regression against other source parameters, or distance, is necessary. Our new method shows promise for integration into earthquake and local tsunami early warning systems, including tsunami earthquakes characterized by relatively slow moment release over a longer rupture time, and earthquakes with complex source time functions. Tsunami Warning Centers are responsible for alerting coastal populations of expected tsunami waves caused by significant earthquakes. Traditionally, warnings rely on rapid magnitude estimation based on distant seismic data. This is sufficient for ocean‐wide tsunami warnings but often not for coastal populations closest to a causative earthquake. More timely warnings for local tsunamis can be obtained by supplementing measurements of seismic accelerations with displacements from Global Navigation Satellite Systems instruments located close to the earthquake source. In this study, we use this data combination to estimate the magnitude of nine historical earthquakes around the Pacific basin. Our real‐time simulations show that we can obtain useful and reliable magnitude estimates for large earthquakes and issue local tsunami warnings within minutes after rupture initiation. Combined seismic and geodetic (seismogeodetic) data enable rapid earthquake magnitude estimatesSeismogeodetic magnitude estimates for very large earthquakes are timelier than those based on seismic data aloneThe seismogeodetic method is applicable to earthquakes with complex source mechanisms, including tsunami earthquakes Combined seismic and geodetic (seismogeodetic) data enable rapid earthquake magnitude estimates Seismogeodetic magnitude estimates for very large earthquakes are timelier than those based on seismic data alone The seismogeodetic method is applicable to earthquakes with complex source mechanisms, including tsunami earthquakes

When Metallica settled its lawsuit against Elektra Records earlier this year, recording artists in California were deprived of a significant opportunity for the courts to examine both the legality and […]

Systematic review of clinical studies.

Resident participation in the Political Action Committee (PAC) is important for professional advocacy and for ensuring access to quality musculoskeletal care. The following questions were asked: Would faculty contribution-matching increase donation rates and amounts among orthopedic surgery residents at a single institution? What barriers do residents self-identify that prevent or delay PAC participation? How do residents perceive a faculty contribution-matching program? Residents at 1 institution were encouraged to participate in the PAC before and after the introduction of a faculty contribution-matching program. In addition, telephone follow-up was performed and resident perceptions were assessed regarding the program and barriers to participation. Rates of participation, amounts donated, and perceptions are reported. Resident participation in the PAC increased from 10% to 95% following the introduction of a faculty contribution-matching program. The second group of residents contributed 67 cents for every dollar given by the first group. Significant barriers identified included time constraints and an inability to access the PAC Web portal. Ninety-four percent of the initial nonresponders said that they made joining the PAC a priority after learning about the faculty contribution-matching program. They specifically cite giving greater attention to an issue that the faculty value. Four months after the initial e-mail, 100% of residents had contributed. Residents believe that professional activism is important but ascribe it a lower priority than other professional duties. Residency programs might facilitate resident involvement in the PAC by instituting faculty contribution-matching and by assisting junior residents with their American Association of Orthopaedic Surgeons login information.

It is estimated that overseas copyright, patent, and trademark piracy costs American businesses some $12 billion to $15 billion annually. The most effective weapon the U.S. has to combat this […]

The initial goals of the treatment of slipped capital femoral epiphysis (SCFE) are to stabilize the epiphysis, prevent slip progression, and avoid complications. In situ fixation with a single screw is the most accepted procedure to provide an optimal fixation, but fixation failure and slip progression suggest that the procedure might be improved. The aim of the present study was to biomechanically compare partially threaded screws (16 mm and 32 mm) and fully threaded screws in an in vitro porcine model.

To determine if community equipoise exists concerning the effectiveness of bracing in adolescent idiopathic scoliosis.

Focuses on the application of percutaneous screw fixation to minimize the complications of slipped capital femoral epiphysis (SCFE). Annual incidence of SCFE according to race, geographic location and sex; Association between obesity and SCFE; Methods for the classification of the disease; Treatment options.

A fundamental goal of research in developmental dysplasia of the hip (DDH) has been the identification of radiographic quantitative factors predictive of long-term outcome. The rapid development of digital imaging modalities opens the possibility for more systematic, automated measurement of radiographs. The authors have developed a software program for the study of DDH that integrates a user interface to select, store, and edit prescribed landmarks on digital radiographs. These points are used to construct and display reference lines analogous to those commonly drawn on physical films. Measurements are stored as a printable text file and as a data record. The results of this study demonstrated very good intrarater and interrater reliability coefficients and intermethod validity coefficients for the digitizing program. If this program is added to a software reporting system, measurements can be done on a real-time basis and can be included in the patient's medical record.

This study examines the long-term results of 22 patients treated between 1938 and 1974 either surgically or by observation. Fourteen patients (16 scapulas) were treated by observation, seven patients (seven scapulas) were treated surgically by various methods, and one bilateral case was treated conservatively on one side and surgically on the other. The average follow-up was 26 years (range, 10–55) and the average age at follow-up was 32 years (range, 18–67). Shoulder abduction and cosmesis did not change appreciably over the years for the patients that did not undergo surgery, but the surgical patients did demonstrate an average improvement in shoulder abduction of 38°. Seven of eight patients treated surgically reported a subjective improvement in the cosmetic appearance at follow-up, although four patients had an unsightly surgical scar. Pain in the affected shoulder was uncommon at follow-up in either group. We feel that the final result should be assessed from the viewpoint of the functional outcome and cosmetic appearance, independent of the radiographic aspect. Surgical treatment for patients with Sprengel's deformity is indicated when patient and family expectations are either improved cosmesis or improved function.

This study retrospectively reviewed the clinical records and radiographs of 11 patients with progressive early-onset scoliosis who failed to respond to nonoperative management and who underwent consecutive distraction of subcutaneous rods. Eleven children were treated by consecutive distraction of subcutaneous rods, and in two patients with rodding and anterior apical fusion. At surgery, the average patient age was 5.66 years, with a mean Cobb angle of 74° and an average Pedriole angle of 39°. The etiology of the scoliosis included four syndromic and one each congenital, post-rib resection, post-spinal tumor resection, neurofibromatosis, myelomeningocele, infantile idiopathic, and juvenile idiopathic. Subcutaneous rodding halted curve progression in all patients. At an average of 5.1 years after surgery, one patient showed no deterioration of the curve and nine patients showed an improvement of ≥40 in the magnitude of the original curvature. Eight of these patients had already had definitive surgery performed with segmental spinal instrumentation and fusion. Spinal growth occurred in all 11 patients and ranged from 0.5 to 4.5 cm (mean 2.0). Early results from these patients show that subcutaneous rodding with consecutive distraction allows correction of progressive early-onset scoliosis that failed to respond to nonsurgical management, preserving the individual growth potential of the spinal column and delaying definitive surgical treatment. Rotational deformity did not deteriorate radiographically, but clinical deformity increased subjectively. The amount of growth achieved and the number of procedures required to obtain these results raises the question of whether patients would be better served by a single anterior, posterior fusion and instrumentation at a young age.

University of Iowa Hospital records from 1926 to 1988 were searched for cases of hip fractures in otherwise healthy children aged between 1 and 16 years. Twenty-six cases were identified. Nineteen patients were available for clinical and radiographic follow-up evaluation. The average follow-up was 16 years postinjury. There were four type I (transepiphyseal), nine type II (transcervical), three type III (cervicotrochanteric), and three type IV (intertrochanteric) femoral fractures. Avascular necrosis (AVN) of the femoral head complicated nine of the 19 fractures (47). Seventy-eight percent of patients who developed AVN required additional surgical intervention to obtain acceptable hip function.

This study presents the results of numerical simulations of a model for lithospheremantle coupling in a terrestrial type planet. To first order, a geologically active terrestrial type planet may consist of a metallic core, silicate mantle and lithosphere, with the lithosphere being rheologically different from the mantle. Therefore we have developed a numerical model consisting of a thin non-Newtonian fluid hoop that is dynamically coupled to a thick Newtonian fluid cylindrical annulus. Thus the rheological dichotomy between mantle and lithosphere is built into the model. Time-dependent calculations show the existence of at least two regimes of behaviors. In one regime, the behavior of the hoop switches between periods characterized by low or high speeds, in response to changes in convective vigor and planform. This regime may apply to the planet Venus where the available evidence indicates that prior to 500 myr ago, the planet was resurfaced on a time scale of <100 myr. Since that time, large-scale tectonic activity on Venus has been sharply curtailed. In the other regime, which is more like plate tectonics on Earth, the hoop speeds rise and fall on short time scales.

The management of hip instability in myelomeningocele patients is controversial. The purpose of this study is to review our long-term results of isolated Chiari osteotomies in the treatment of hip instability in children with myelomeningocele. Between 1975 and 1988, 11 patients underwent 13 Chiari osteotomies for reducible hip subluxation or dislocation and acetabular deficiency. The patients returned for follow-up clinical examinations, interviews, and radiographs. The average age at the time of surgery was 9.4 years (range, 5-18). The average age at follow-up was 18 years (range, 13-23). The average follow-up was 11.4 years (range, 2-18). The mean preoperative center-edge (CE) angle was -38°. The mean immediate postoperative CE angle was 41°. At final follow-up, the mean CE angle was 4.6°. Only three of the 10 hips had a normal CE angle of≥25°. The Chiari osteotomy alone did not achieve long-term hip stability in the majority of patients. Several, if not most, of our patients may progress to frank dislocation with longer follow-up.

When evaluating patients with neurofibromatosis and scoliosis, a careful search for the evidence of dystrophic changes should done, because prognosis and management depend highly on the presence of these changes. Preoperative imaging studies including computed tomography or magnetic resonance imaging are recommended, especially in cases of dystrophic scoliosis, to detect unrecognized intraspinal lesions. The radiographic findings and the response to treatment in patients with nondystrophic scoliosis are similar to those in patients with idiopathic scoliosis, and the same decisionmaking process for idiopathic scoliosis is applicable. Careful followup evaluation is mandatory, however, because of the tendency for extraordinary progression to occur with growth. Brace treatment of the short, angulated, dystrophic curves is ineffective early and aggressive surgical intervention is strongly recommended. In most cases, dystrophic curvatures are best treated with combined anterior and posterior spinal arthrodesis. The fusion area should be generous, and the entire structural area of the deformity both anteriorly and posteriorly should be fused.

A retrospective review of consecutive pediatric and adolescent patients who required posterior spinal fusion to correct scoliosis.

A case report is presented of an unusual complication of scoliosis surgery that, to the authors' knowledge, has never been reported in the literature.

The low back injured worker presents a challenging problem to medicine and industry alike. The economic burden on society is staggering. Medical care has thus far not been very effective in managing this complex biopsychosocial illness. A trend toward more organized involvement between industry and health care has been demonstrated to have a positive impact on this growing epidemic.

Epidural injections in the cervical, thoracic, and lumbosacral spine have become important tools in the management of painful spine conditions. These injections should be carefully integrated into a comprehensive rehabilitation treatment plan. Well-controlled anesthetic and corticosteroid injections given with fluoroscopic guidance can help distinguish active pain generators from nonpainful structural abnormalities. This article presents various approaches and injection techniques that are used to selectively treat the tissues most often causing pain within and adjacent to the epidural space.

Numerical simulations of two-dimensional time-dependent thermal convection in a Boussinesq, isoviscous, infinite Prandtl number fluid with isothermal, stress-free boundaries have been performed in large aspect-ratio configurations, in which the fluid is heated from below as well as internally. The value of the basal heated Rayleigh number ranged from 16000 to 800 000 and the Rayleigh number based on internal heat generation was varied from zero to 4 500 000. Large aspect-ratio cells are found to exist, however, they are time-dependent even at small values of the Rayleigh number. In the absence of internal heating, the onset of time-dependence occurs as a regular oscillation in the flow characteristics (Nusselt number, kinetic energy), and is accompanied by the presence of boundary layer instabilities (BLI) which exist within a large aspect-ratio circulation. At high values of the Rayleigh number the BLI are powerful features which leave the confines of the boundary layer and strongly perturb the large aspect-ratio circulation giving the flow a multi-scale character. Convective mixing of these powerful BLI results in heterogeneity in the cell interior which plays a role in the excitation of new BLI and establishes a negative temperature gradient in the cell interior. We have developed a fluid loop model which gives a qualitative explanation for the variation of the onset of time-dependence with aspect-ratio. The addition of internal heating tends to destabilize the large aspect-ratio cell configuration. Multi-cellular states last longer and occur more frequently with increasing amounts of internal heating. These calculations shed new light on a variety of time-dependent phenomena in geodynamics such as subduction, back-arc spreading, intraplate deformation, and the average geotherm. Recently, Jeanloz and Morris proposed that the seismic inhomogeneity parameter (η) can be used to measure the importance of internal heating in mantle convection. However, our calculations indicate that η cannot be used to gauge the importance of internal heating in mantle convection.

We report the principles and method developed by Dr. I. V. Ponseti for correction of clubfoot. The aim of the treatment is early and full correction of all components of the deformity by gentle manipulations and well-molded plaster casts. All components of the clubfoot deformity must be corrected simultaneously, not in sequence, except for equinus, which should be corrected last. A percutaneous tendo achillis tenotomy may be needed to facilitate correction of equinus. To prevent recurrences, the corrected feet must be maintained in outward rotation in open shoes attached to a bar for many months. The results, although often not anatomically perfect, as viewed on roentgenograms, are almost perfect clinically and functionally, at least into the fifth decade of the patient's life.

Fluoroscopy and three-dimensional CT analysis were used to define the contributing anatomy and changes in appearance of the tear-figure with rotation of a pelvis. The tear-figure is a cortical structure of iliac and ischial bone that appears on anteroposterior (AP) roentgenograms of the pelvis. The contribution of these cortices to the pelvic tear-figure changes with rotation of a pelvis in a radiographic field. Cortices contributing to the tear-figure are not continuous throughout. The lateral border, inferior margin, and inferior one third of the medial border of the tear-figure is formed by a continuous segment of cortical bone extending from the deepest portion of the acetabulum around the cylindric acetabular notch, and along the inferior medial wall of the ischium. The superior two thirds of the medial border of the tear-figure consists of cortical bone extending superiorly along the medial wall of the ilium, which is not in continuity with the remainder of the components of the tear-figure. The tear-figure is not a structure of constant radiographic dimension. Its apparent dimensions change with rotation of the pelvis. The positioning of the patient for the AP pelvic roentgenogram is thus important when studying the effects of acetabular pathology on the appearance of the pelvic tear-figure.

Psychosocial characteristics of 95 female patients treated with Milwaukee bracing for idiopathic scoliosis were examined using a battery of five psychosocial scales. Sixty-five patients treated with bracing alone and 30 patients who also underwent arthrodesis for curve progression were compared with 49 age-matched female controls. At an average follow-up of 7 years, no differences in depression or health locus of control existed. Significant perceptions of discrimination and a lower satisfaction of overall appearance was recalled during the treatment phase. By final follow-up, there was no longer any difference between the patients and controls in these areas. Significantly, differences in body-image scores persisted at follow-up. Operative patients had a more negative body image of the axial skeleton in comparison with the braced and control groups. We conclude that transient psychological effects are often present during treatment, and a lower body image may persist for several years in surgical patients.

Epidural steroid injections are commonly used for the management of lumbosacral radicular syndromes. The literature is replete with case reports and noncontrolled studies, but relatively few controlled studies exist. The well-designed studies that are available, however, do show a significantly positive pain reducing benefit from lumbar epidural steroid injections. This Contemporary Conceptsreview summarizes theoretic concepts, clinical applications, and data from the literature regarding the use of lumbar epidural steroid injections and provides current recommendations and suggestions for future research.

Of 102 hips with femoral neck fracture complications, 75 required major secondary procedures such as total hip replacement, femoral prosthesis, cup arthroplasty, tibial bone grafting, and head and neck resection. The method chosen depended on the specific problem: nonunion, aseptic necrosis, infection, degenerative arthritis, or a failed primary prosthesis. Other factors influencing treatment were the patient's chronological and physiological age, his general health, his life pattern, and the familiarity of the surgeon with the technique and the advantages and disadvantages of the various salvage procedures.

A 3,7-year follow-up study of 25 cerebral palsied children with 41 adductor tenotomies and obturator neurectomies showed significant improvement in hip abduction and acetabular development.

A retrospective review of 24 cases of adolescent idiopathic scoliosis (AIS). Intraoperative push–prone test to determine the lowest instrumented vertebrae (LIV).

WEINSTEIN, S. M. and R. C. CANTU. Cerebral stroke in a semi-pro football player: a case report. Med. Sci. Sports Exerc., Vol. 23, No. 10, pp. 1119–1121, 1991. Cervical spine trauma can clearly result in neurologic injury. An unusual traumatic event is a vascular insult of the vertebral arteries, potentially leading to stroke. The vertebral arteries are vulnerable to compression at several sites in the cervical spine. The high degree of physiologic rotation at the atlanto-axial joint places the vertebral artery at risk through normal daily activities as well as following forceful trauma, including manipulative treatment. Cerebrovascular insufficiency is an uncommon but serious complication of cervical spinal manipulation, which can lead to posterior circulatory impairment. Comprehensive diagnostic studies may be required to differentiate primary intracranial pathology from cerebral symptoms secondary to vascular compromise.