EDF Casting for Early Onset Scoliosis: What We Learned From 175 Castings.

STUDY DESIGN: IRB approved prospective case series. OBJECTIVES: This study attempts to determine the effects of elongation, derotation, and flexion (EDF) casting on pulmonary function. We also attempted to define prognostic factors and determine the ideal amount of traction for casting in patients with early onset scoliosis (EOS). SUMMARY OF BACKGROUND DATA: No literature on effects of serial casting on pulmonary parameters in EOS, or on the ideal amount of traction to be used for EOS Casting. METHODS: Fifty consecutive children with EOS treated by the senior author using EDF casting were studied prospectively. Traction and lung function parameters (compliance, tidal volume, peak inspiratory pressure, and resistance) were measured at different periods during cast application. Etiology, age, weight, Cobb angles, and RVAD were monitored. RESULTS: All lung function parameters decline during cast application but rise to near baseline levels at the time of next cast application. Near full curve correction was achieved in every patient with (A) idiopathic scoliosis who (B) presented prior to 20 months of age with (C) a moderate main curve at presentation (<45°) and in those (D) without a phase II rib-vertebral relationship at presentation. The best response to casting was seen with 1 pound traction per pound body weight during application. CONCLUSION: EDF casting can delay progression or improve curves in patients with larger curves, nonidiopathic scoliosis, and older patients. Idiopathic patients, moderate curve sizes, and younger patients had a better response to casting. Even though lung function declines during cast application, it returns to near baseline levels at the time of the next cast application, suggesting that EDF casting may not have any long-term effects on lung function, and also may protect pulmonary function in EOS from its natural history of progressive deterioration.Level of Evidence: 4.

Orthopedic guidelines for the care of people with spina bifida.

Orthopedic or musculoskeletal problems are common in individuals with spina bifida. They can affect function and mobility and, in the case of spinal deformity, affect pulmonary function. We discuss the current treatment guidelines developed through collaboration with the Spina Bifida Association and the Orthopedics and Mobility working group using a specific methodology previously reported [1,2]. General considerations are discussed followed by evaluation and treatment guidelines for specific age ranges. References are provided where applicable, but where data is lacking treatment guidelines fall under the umbrella of clinical consensus. This leaves "research gaps" where areas of possible future study could be considered.

Evolution of casting techniques in early-onset and congenital scoliosis.

Casting is being utilized as a therapeutic strategy in some mild to moderate cases obviating surgical intervention for management of early-onset scoliosis (EOS). Bracing, another conservative modality, applies comparable correcting forces on chest wall and axial skeleton. But cast application carries additional advantage of sustained restorative force which bypasses issue of compliance seen with brace wear. There is no specific blanket treatment, conservative or surgical, for the early-onset spinal deformities. Serial cast application provides near total correction of less severe curves (less than 500 to 600) if treatment is initiated before age of 2 yrs. In this review article, we will assess the evolution of plaster cast application in management of EOS and also describe technique of EDF (Elongation- Derotation- Flexion) casting.

Intraobserver and Interobserver Measurement Variability of the Rib-Vertebral Angle Difference.

BACKGROUND: The rib-vertebral angle (RVAD) differentiates between progressive and resolving infantile idiopathic scoliosis (IIS) curves. Those with a RVAD<20 degrees often resolve without treatment, whereas those >20 degrees often progress and require treatment. The mathematical magnitude of RVAD measurement variability has not been described, and was thus the purpose of this study. It is important to know the reliability of RVAD measurements so as to understand changes that can be attributed to observer error alone. PURPOSE: The purpose of the study was to mathematically determine the intraobserver and interobserver measurement variability of the RVAD difference in IIS. METHODS: A convenience sample of 50 patients with IIS was selected. The RVAD was measured twice by 7 different observers separated by a minimum of 3 weeks. The 7 different readers chosen to measure the RVAD were 2 orthopaedic residents, 1 pediatric radiologist, and 4 attending pediatric orthopaedic surgeons. The same goniometer was used for all measurements. Intraobserver and interobserver measurement variability was determined using 3 well known used statistical methods. RESULTS: The 3 different methods used to determine intraobserver and interobserver variability using 95% prediction/confidence limits gave very similar results. Intraobserver variability was ∼24 degrees and the interobserver variability was ∼23 degrees. DISCUSSION: The utility of the RVAD in medical decision-making and counseling of patients with IIS should be approached with caution when used in isolation due to the large measurement variability. LEVEL OF EVIDENCE: Level 3.

Comparison Between Gearshift And Drill Techniques For Pedicle Screw Placement By Resident Surgeons.

BACKGROUND: Various techniques have been described for pedicle screw placement with established clinical and radiological success. Suboptimal screw trajectories can compromise bony purchase and, worse yet, cause neurological and vascular injuries. Thus, it is of paramount importance to achieve maximum accuracy of screw placement. Our objective is to evaluate the accuracy of pedicle screw placement in the thoracolumbar spine by resident surgeons. Two popular techniques, gearshift versus drill, were compared. METHODS: This is a a cadaveric surgical technique comparison study. Six resident surgeons instrumented the spine from T1 to S1 using both gearshift and drill techniques. Each pedicle was randomly assigned to either of the techniques. Pedicle screws were placed freehand without radiographic guidance. Violations (medial, lateral, anterior, superior and inferior) were recorded by studying the computerized tomographic scans of instrumented cadavers by blinded observers. Critical perforations were defined as greater than 2mm breach of the pedicle wall. RESULTS: A total of 100 vertebrae (200 pedicles) were instrumented in the six cadavers. 103 pedicles were breached (51.5% of total pedicles). Lateral violations were the most encountered (65% of violations, 67 total, 48 critical, 19 noncritical) followed by medial (24%, 25 total, 13 critical, 12 noncritical), and the rest were anterior (3%), superior (4%) and inferior (4%). There was no overall difference in violations comparing the gearshift technique (49.5%, 51 total, 37 critical, 14 noncritical) with drill technique (50.5%, 52 total, 33 critical, 19 noncritical). Analyzing the breaches at individual vertebra indicated most violations at T6 (11), T5 (10), followed by T3 (9) and T4 (9), decreasing towards the lumbosacral vertebrae. CONCLUSION: The results of this study suggest that the gearshift and drill techniques for placement of pedicle screws in the thoracolumbar spine fare similarly with regards to risk of breach when applied by resident surgeons.

Derotational casting for progressive infantile scoliosis.

BACKGROUND: Serial cast correction by using the Cotrel derotation technique is one of several potential treatments for progressive infantile scoliosis. This study reviews our early experience to identify which, if any, patients are likely to benefit from or fail this technique. METHODS: We followed all patients treated at our institutions for progressive infantile scoliosis since 2003 prospectively at 1 institution and retrospectively at the other 2. Data, including etiology, Cobb angles, rib vertebral angle difference, Moe-Nash rotation, and space available for the lung, were recorded over time. RESULTS: Fifty-five patients with progressive infantile scoliosis had more than 1 year of follow-up from the initiation of casting. The diagnosis of progressive scoliosis was made based upon either a progressive Cobb angle or a rib vertebral angle difference of more than 20 degrees at presentation. All but 6 patients responded to cast correction. Nine patients have undergone surgery to date, 6 because of worsening and 3 by parent choice. As shown in the table, initiation of cast correction at a younger age, moderate curve size (<60 degrees), and an idiopathic diagnosis carry a better prognosis than an older age of initiation, curve >60 degrees, and a nonidiopathic diagnosis. The space available for the lung improved from 0.89 to 0.93. No patient experienced worsening of rib deformities. CONCLUSIONS: Serial cast correction for infantile scoliosis often results in full correction in infants with idiopathic curves less than 60 degrees if started before 20 months of age. Cast correction for older patients with larger curves or nonidiopathic diagnosis still frequently results in curve improvement along with improvement in chest and body shape. SIGNIFICANCE: Derotational cast correction seems to play a role in the treatment of progressive infantile scoliosis with cures in young patients and reductions in curve size with a delay in surgery in older and syndromic patients. LEVEL OF EVIDENCE: Level 4, therapeutic study.

Spinal injuries in pedestrians struck by motor vehicles.

STUDY DESIGN: Retrospective study of consecutive patients that were struck by motor vehicles and sustained spinal injuries over a 6-year period from 1997 to 2003. OBJECTIVE: To determine spinal injury patterns and associated injuries in pedestrians struck by motor vehicles. SUMMARY OF BACKGROUND DATA: Motor vehicle accidents involving pedestrians are associated with high morbidity and mortality rates. METHODS: All injured patients admitted to Level I Trauma and Regional Spinal Cord Injury Center were reviewed retrospectively to identify those who were struck by motor vehicles and sustained injury to the spinal column. Before 2001, clearance of the thoracolumbar (TL) spine was performed by plain radiographs. Beginning in 2001, such clearance was performed by helical truncal computed tomography of the chest/abdomen/pelvis (CT/CAP) that was performed to evaluate potential visceral injuries. RESULTS: Of the 1672 patients who were struck by motor vehicles, 135 patients (8%) were found to have spinal injuries. Cervical injuries were found in 35%, thoracic in 19%, lumbar in 37%, and sacral injuries in 27%. Associated injuries were present in 99% of the patients. By relative risk analyses, there were no regional associations between injuries of the TL spine and injuries to the chest and abdomen. Patients frequently had combinations of injuries in distant locations, presumably from a "double-impact" injury mechanism. Before initiation of the CT/CAP protocol to clear the TL spine, 7% of patients had injuries initially missed by TL radiographs. CONCLUSIONS: Spinal injuries in pedestrians struck by motor vehicles are more evenly distributed throughout the spinal column and more often coexist with injuries to remote organs compared with car occupants and motorcyclists where regional tendencies and isolated spinal injuries are more frequent. A systematic approach to both diagnosis and treatment is, therefore, necessary. Helical truncal CT, performed to evaluate visceral injury, effectively screens for TL fractures.

Predicting scoliosis progression from skeletal maturity: a simplified classification during adolescence.

BACKGROUND: Both the Tanner-Whitehouse-III RUS score, which is based on the radiographic appearance of the epiphyses of the distal part of the radius, the distal part of the ulna, and small bones of the hand, and the digital skeletal age skeletal maturity scoring system, which is based on just the metacarpals and phalanges, correlate highly with the curve acceleration phase in girls with idiopathic scoliosis. However, these systems require an atlas and access to the scoring system, making their use impractical in a busy clinical setting. We sought to develop a simplified system that would correlate highly with scoliosis behavior but that would also be rapid and reliable for clinical practice. METHODS: A simplified staging system involving the use of the Tanner-Whitehouse-III descriptors was developed. It was tested for intraobserver and interobserver reliability by six individuals on thirty skeletal age radiographs. The system was compared with the timing of the curve acceleration phase in a cohort of twenty-two girls with idiopathic scoliosis. RESULTS: The average intraobserver unweighted kappa value was 0.88, and the average weighted kappa value was 0.96. The percentage of exact matches between readings for each rater was 89%, and 100% of the differences were within one unit. The average interobserver unweighted kappa value was 0.71, and the average weighted kappa value was 0.89. The percentage of exact matches between two reviewers was 71%, and 97% of the interobserver differences were within one stage or matched. The agreement was highest between the most experienced raters. Interobserver reliability was not improved by the use of a classification-specific atlas. The correlation of the staging system with the curve acceleration phase was 0.91. CONCLUSIONS: The simplified skeletal maturity scoring system is reliable and correlates more strongly with the behavior of idiopathic scoliosis than the Risser sign or Greulich and Pyle skeletal ages do. The system has a modest learning curve but is easily used in a clinical setting and, in conjunction with curve type and magnitude, appears to be strongly prognostic of future scoliosis curve behavior.

Thoracoscopic scoliosis surgery affects pulmonary function less than thoracotomy at 2 years postsurgery.

STUDY DESIGN: Prospective evaluation of pulmonary function before and 2 years after surgery following anterior scoliosis instrumentation. OBJECTIVES: To determine if thoracoscopic anterior scoliosis correction with instrumentation affected pulmonary function less than open thoracotomy approaches at 2 years follow-up. SUMMARY OF BACKGROUND DATA: The thoracoscopic approach has been shown to have a smaller reduction in pulmonary function tests (PFTs) compared with an open thoracotomy approach following anterior thoracic instrumentation for adolescent idiopathic scoliosis in the immediate postoperative period; however, it is unclear if a difference remains 2 years following the procedure. METHODS: A total of 107 patients in a multicenter adolescent idiopathic scoliosis database underwent an anterior instrumented fusion for thoracic scoliosis. PFTs assessing forced vital capacity (FVC), forced expiratory volume (FEV1), and total lung capacity (TLC) were obtained prospectively before and 2 years after surgery. The patients were grouped as follows: Group I, thoracoscopic instrumented fusion (n = 36); Group II, open (thoracotomy) instrumented fusion without thoracoplasty (n = 28); and Group III, open instrumented fusion with thoracoplasty (n = 43). RESULTS: Thoracoscopic instrumentation affected pulmonary function 2 years after surgery minimally, and on an average showed improvements in all parameters except the percent-predicted FVC, which decreased by 1% +/- 11%, and percent predicted FEV, which decreased by 2% +/- 9%. Improvements were noted in absolute FVC, FEV1, TLC, and percent-predicted TLC. This is in contrast to the patients treated with a thoracotomy, who had a greater persistent reduction in PFTs at follow-up. An added thoracoplasty to the thoracotomy approach, however, resulted in even greater residual reduction in PFTs at follow-up, with declines in percent-predicted FVC of 15%, percent-predicted FEV1 of 14%, and percent-predicted TLC of 8%. CONCLUSIONS: This study shows a clear advantage to the minimally invasive thoracoscopic approach with regards to pulmonary function when compared with the open thoracotomy approaches.

A technique for calculating limb length inequality and epiphyseodesis timing using the multiplier method and a spreadsheet.

PURPOSE: Limb length inequality and epiphyseodesis timing calculations are common in pediatric orthopedics. The multiplier method developed by Paley et al. has significantly simplified the calculation of ultimate limb length. The calculation of limb length inequality has also become very simple for congenital limb length inequalities. However, the equations for limb length inequality from acquired differences and epiphyseodesis timing are not simple, and are prone to arithmetic errors. METHODS: To limit these errors, we have developed a spreadsheet which finds the appropriate multipliers, solves the equations, and computes the predicted limb length inequality and the appropriate age for an epiphyseodesis. RESULTS: This method of using a spreadsheet and the multiplier calculations is quite simple and quick to use in practice. The calculations can be cut and pasted into computerized charts for future reference. CONCLUSIONS: We recommend this method for clinical use and make it available for public use.

Biomechanical stability of single-screw versus two-screw fixation of an unstable slipped capital femoral epiphysis model: effect of screw position in the femoral neck.

PURPOSE: To biomechanically evaluate single screw and varying 2 screw fixations for an unstable slipped capital femoral epiphysis (SCFE) model using physiologically relevant loading. STUDY DESIGN: In vitro biomechanical study. METHODS: Twenty-four immature porcine proximal femurs were prepared to simulate a mild-to-moderate unstable SCFE. The femurs were randomized into 4 fixation groups: single screw, 2 screws horizontally placed, 2 screws vertically placed, and 2 oblique screws. Biomechanical testing determined maximum load to failure (N), load (N) at 2, 4, 6, and 8 mm of femoral head displacement, and stiffness (newtons per millimeter) for each group. RESULTS: No significant differences were found among the 3 different 2 screw configurations. The 2 screw constructs were 66% stiffer and 66% stronger than the single screw construct. In addition, whereas there was no difference at 2 mm of femoral head displacement, each subsequent displacement (4, 6, and 8 mm) demonstrated significantly higher failure loads when 2 screws were used for stabilization. CONCLUSIONS: Slipped capital femoral epiphysis stabilization with 2 screws leads to increased stability over single screw fixation; however, none of the 3 configurations/placement patterns of the 2 screw constructs seemed to be superior in fixation stability. CLINICAL RELEVANCE: These data support the use of a 2 screw construct in acute/unstable SCFE fixation. The biomechanical benefit of 2 screws needs to be considered in the face of greater potential for inadvertent penetration into the joint with an increased number of screws.

Biomechanical analysis of single screw fixation for slipped capital femoral epiphysis: are more threads across the physis necessary for stability?

PURPOSE: To evaluate single screw fixation stability, in the treatment of slipped capital femoral epiphysis, as a function of screw thread distribution across the physis. STUDY DESIGN: In vitro biomechanical study. METHODS: Thirty porcine proximal femurs were sectioned through the physeal line and stabilized with a cannulated 7.3-mm stainless steel AO screw. The distal 16 mm of each screw was threaded (5 threads). The femurs were randomized into 5 groups (1, 2, 3, 4, or 5 threads across the physis) and biomechanically tested to determine failure load (N) and stiffness (N/mm). RESULTS: Femurs with 2 or 3 threads across the physis had a significantly greater load to failure and stiffness compared with femurs with 1, 4, or 5 threads across the physis (P < 0.05). CONCLUSIONS: Thread distribution across the physis seems to be important. When using screws with a 16-mm thread, greatest strength and stiffness are achieved when 40%-60% of threads engage the epiphysis, with a significant decrease when greater than 80% of threads cross the physis. Too few threads in the epiphysis as well as too few in the metaphysis both lead to decreased stability. CLINICAL RELEVANCE: This study challenges the belief that compression across the physis maximizes slipped capital femoral epiphysis fixation stability. We recommend equal distribution of threads across the physis when using 16-mm thread screws, and we postulate that screws with a greater thread length (32 mm or fully threaded) would increase fixation stability even further. Optimizing purchase may decrease the incidence of slip progression, especially as the prevalence of obesity increases in the adolescent population.

Impingement and childhood hip disease.

Hip impingement is now recognized as a relatively common cause for hip pain in young adults. The early evolution of impingement begins in childhood in several common hip disorders (slipped capital femoral epiphysis, Perthes, early avascular necrosis due to other causes). Recognition and treatment of childhood impingement may prevent the evolution to early hip arthritis.

Principles of external fixation of the femur.

External fixation may be indicated for a variety of traumatic and reconstructive conditions involving the femur. Regardless of underlying pathology and type of external fixator used, fixator placement requires a clear understanding of the unique skeletal and soft-tissue anatomy of the femur. In this review, we outline the principles of safe and effective placement of external fixation for the femur. By following these guidelines regarding femur anatomy and alignment, proper pin-insertion techniques, and aftercare, surgeons should be able to obtain satisfactory results for the majority of appropriately selected patients.

Timing of surgery following spinal cord injury.

BACKGROUND: The optimal timing for surgical intervention after traumatic spinal injuries with spinal cord injury remains unclear. DESIGN: Literature review. FINDINGS: Multiple laboratory investigations (in animal models) and many clinical studies suggest better neurological outcomes with early surgical intervention. Conclusive evidence (well-designed randomized, controlled studies), however, is lacking, partly due to the logistics involved in executing such an investigation. Early surgery also appears to decrease the incidence of complications, reduces hospital stay, and helps reduce costs associated with acute management. CONCLUSION: Early surgical treatment is beneficial in terms of reducing complications, length of stay, and hospital costs. Further studies are needed to clearly demonstrate the impact of operative timing on neurological outcome.

Posttraumatic pediatric distal tibiofibular synostosis: a case report.

INTRODUCTION: Posttraumatic pediatric distal tibiofibular synostosis is a rare complication of fractures at this level, unreported at this time. Implications include limb length discrepancy, angular malalignment, and gait and biomechanical abnormalities. MATERIALS AND METHODS: The authors present a case report of this complication in a 7-year-old child and review the relevant English literature. The patient was treated for a closed distal tibia-fibula fracture and developed a synostosis at that level, with valgus malalignment of the ankle joint. The synostosis was resected and latest follow-up 16 months postresection showed near normalization of the ankle malalignment. Possible etiologies, the anatomical and functional ramifications, and treatment recommendations for this condition are discussed. SUMMARY: Posttraumatic tibiofibular synostosis is a rare complication that has a potential effect on limb length and alignment, both at the ankle and the knee in the skeletally immature patient. Prevention, early recognition, and prompt treatment prevent the anatomic and functional abnormalities that could result from it.