Lindsay M. Andras

Early-Onset Scoliosis: A Review of History, Current Treatment, and Future Directions

Early-onset scoliosis (EOS) is defined as curvature of the spine in children >10° with onset before age 10 years. Young children with EOS are at risk for impaired pulmonary function because of the high risk of progressive spinal deformity and thoracic constraints during a critical time of lung development. The treatment of EOS is very challenging because the population is inhomogeneous, often medically complex, and often needs multiple surgeries. In the past, early spinal fusion was performed in children with severe progressive EOS, which corrected scoliosis but limited spine and thoracic growth and resulted in poor pulmonary outcomes. The current goal in treatment of EOS is to maximize growth of the spine and thorax by controlling the spinal deformity, with the aim of promoting normal lung development and pulmonary function. Bracing and casting may improve on the natural history of progression of spinal deformity and are often used to delay surgical intervention or in some cases obviate surgery. Recent advances in surgical implants and techniques have led to the development of growth-friendly implants, which have replaced early spine fusion as the surgical treatment of choice. Treatment with growth-friendly implants usually requires multiple surgeries and is associated with frequent complications. However, growth-friendly spine surgery has been shown to correct spinal deformity while allowing growth of the spine and subsequently lung growth.

Iatrogenic nerve injuries in the treatment of supracondylar humerus fractures: are we really just missing nerve injuries on preoperative examination?

Background: Recent studies report the rate of iatrogenic nerve injury in operatively treated supracondylar humerus (SCH) fractures is 3% to 4%. A reliable neurological examination can be difficult to obtain in a young child in pain. We hypothesized that nerve injuries may be missed preoperatively, later noted postoperatively in a more compliant patient, and then falsely considered an iatrogenic injury. Methods: A prospective study was conducted on patients who presented between April 2011 and April 2013 with an extension-type SCH fracture that was managed surgically. A neurological examination was performed preoperatively, postoperatively, and at follow-up visits by a fellowship-trained attending pediatric orthopaedic surgeon. Only patients in whom the attending surgeon felt a reliable neurovascular examination was obtained were included in this study. Results: Of the 100 patients, 16% had a nerve injury recognized on preoperative examination and 3% had a new nerve injury on postoperative examination (1 anterior interosseous, 1 median sensory, and 1 radial motor). The Gartland type (P=0.421), type of reduction (open vs. closed; P=0.720), and number of lateral-entry (P=0.898) or medial-entry (P=0.938) pins used were not associated with patients who had a new nerve injury found postoperatively. A trend was seen between fracture severity and rate of a preoperative nerve injury: type II 7% (2/28), type III 19% (9/58), and type IV 36% (5/14) (P=0.058). Preoperatively, nerve injuries were noted at the following rates: median 12% (12/100) (including 8 anterior interosseous nerve injuries), radial 8% (8/100), ulnar 3% (3/100). Conclusions: In this prospective study, in patients who were able to comply with a preoperative neurological examination done by an attending pediatric orthopaedic surgeon, the rate of iatrogenic nerve injury after operative treatment of SCH fractures is 3%. We conclude that this finding is true, and not a result of inadequate preoperative neurological examinations. Level of Evidence: Level I prognostic study.

Use of a Novel Pathway for Early Discharge Was Associated With a 48% Shorter Length of Stay After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

Introduction: Hospital stay after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) has decreased only modestly over time despite a healthy patient population. The purpose of this study was to evaluate the impact of a novel postoperative pathway on length of stay (LOS) and complications. Methods: A retrospective review of patients undergoing PSF for AIS in 2011 to 2012 was performed at 2 institutions evaluating demographics, preoperative Cobb angles, surgical duration, blood loss, LOS, and postoperative complications. Patients at one center were managed using an accelerated discharge (AD) pathway emphasizing early transition to oral pain medications mobilization with physical therapy 2 to 3 times/d, and discharge regardless of return of bowel function. Expectations were set with the family before surgery for early discharge. Patients at the other center were managed without a standardized pathway. Results: One hundred five patients underwent PSF and were treated by an AD pathway, whereas 45 patients were managed using a traditional discharge (TD) pathway. There was no difference in proximal thoracic and main thoracic Cobb magnitudes and a small difference in thoracolumbar curve magnitudes (35.2±13.0 degrees AD vs. 40.6±11.4 degrees TD, P=0.004) between groups. Surgical time was slightly shorter in AD patients (median 3.1 vs. 3.9 h, P=0.0003) with no difference in estimated blood loss. LOS was 48% shorter in the AD group (2.2 vs. 4.2 d, P<0.0001). There was no difference in readmissions or wound complications between groups. Conclusions: Hospital stay was nearly 50% shorter in patients managed by the AD pathway without any increase in readmissions or early complications. Significance: Discharge after PSF for AIS may be expedited using a coordinated postoperative pathway. No increase in complications was seen using the AD pathway. Earlier discharge may reduce health care costs and allow an earlier return to normalcy for families. Level of Evidence: Level III—case control study.

Comparison of Outcomes After Posterior Spinal Fusion for Adolescent Idiopathic and Neuromuscular Scoliosis: Does the Surgical First Assistantʼs Level of Training Matter?

Study Design. This was a retrospective review of posterior spinal fusion surgical procedures in patients diagnosed with adolescent idiopathic scoliosis (AIS) or neuromuscular scoliosis (NMS). Objective. The purpose was to determine if the first assistants training experience is associated with outcomes in AIS and NMS surgical procedures. Summary of Background Data. A previous study found that patients with AIS undergoing posterior spinal fusion with 2 attendings had similar operating times, blood loss, and complication rates compared with those with a resident or fellow first assistant. NMS cases are more complex than AIS cases, but to our knowledge, no previous studies have examined the impact of the first assistants level of training on NMS outcomes. Methods. This was a single-center retrospective review of 200 patients, 120 with AIS and 80 with NMS, undergoing primary posterior spinal fusion. Minimum follow-up was 2 years. For each diagnosis group, cases assisted by junior orthopedic residents were compared with those assisted by orthopedic fellows. Results. NMS cases were more complex and had higher complication rates than AIS cases (P < 0.05). AIS and NMS cases were similarly distributed among the fellow and junior resident groups (P = 0.63). AIS cases in the fellow and junior resident groups had similar operating times, estimated blood loss (EBL), complications, lengths of stay, and reoperation rates (P > 0.05). In NMS cases, the fellow group had shorter operating times (320 ± 73 min vs. 367 ± 104 min, P = 0.035) and greater percent correction at initial and 2-year follow-up (58 ± 15% vs. 42 ± 19%, P < 0.001). EBL, complications, lengths of stay, and reoperation rates were similar between the assistant groups in NMS cases (P > 0.05). Conclusion. NMS surgical procedures in which fellows serve as the first assistants were associated with shorter operating times and greater percent correction than surgical procedures with junior resident first assistants. Level of Evidence: 3

Supracondylar Humeral Fractures with Isolated Anterior Interosseous Nerve Injuries: Is Urgent Treatment Necessary?

BACKGROUND It is unclear if pediatric patients with a supracondylar humeral fracture and isolated anterior interossous nerve injury require urgent treatment. METHODS A retrospective, multicenter study of 4409 patients with operatively treated supracondylar humeral fractures was conducted. Exclusion criteria were additional nerve injuries other than the anterior interosseous nerve, any sensory changes, pulselessness, ipsilateral forearm fractures, open fractures, less than two months of follow-up, or pathological fractures. RESULTS Thirty-five of 4409 patients met inclusion criteria. The average time to surgery was 14.6 hours (range, two to thirty-six hours). No patient developed compartment syndrome. There was no significant difference in time to return of anterior interosseous nerve function relative to the time to surgical reduction and fixation (p = 0.668). A complete return of anterior interosseous nerve function occurred in all patients with an average time of forty-nine days (range, two to 224 days). Ninety percent of patients recovered anterior interosseous nerve function by 149 days. CONCLUSIONS To our knowledge, this is the largest series to date of supracondylar humeral fractures with anterior interosseous nerve injuries. There is no evidence that a supracondylar humeral fracture with an isolated anterior interosseous nerve injury requires urgent treatment. A delay in treatment up to twenty-four hours was not associated with an increased time of nerve recovery or other complications. This series excluded patients with sensory nerve injuries, pulselessness, and ipsilateral forearm fractures, which all may require urgent surgery. Barring other clinical indications for urgent treatment of a supracondylar humeral fracture, an isolated anterior interosseous nerve injury (no sensory changes) may not by itself be an indication for urgent surgery. The anterior interosseous nerve injuries in this series showed complete recovery at a mean time of forty-nine days.

Fever is common postoperatively following posterior spinal fusion: infection is an uncommon cause.

OBJECTIVE To determine the frequency and clinical significance of postoperative fever in pediatric patients undergoing posterior spinal fusion (PSF). STUDY DESIGN A retrospective chart review was performed for consecutive patients undergoing PSF at a single institution between June 2005 and April 2011, with a minimum of 2-year follow up. Exclusion criteria were previous spine surgery, a combined anterior-posterior approach, and delayed wound closure at the time of surgery. RESULTS Two hundred and seventy-eight patients with an average age of 13 years (1-22 years) met inclusion criteria, with the following diagnoses: adolescent idiopathic scoliosis 43%, neuromuscular/syndromic scoliosis 39%, congenital scoliosis 11%, spondylolisthesis 4%, and Scheuermann kyphosis 3%. Seventy-two percent (201/278) of patients had a maximum temperature (Tmax) >38(°) postoperatively, and 9% (27/278) Tmax >39(°). The percentage of febrile patients trended down following the first postoperative day. Infection rate was 4% (12/278). There was no correlation between Tmax >38(°) or Tmax >39(°), and timing of fever, positive blood or urine cultures, pneumonia, or surgical site infection. CONCLUSION Seventy-two percent of pediatric patients undergoing PSF experienced postoperative fever, and 9% of patients had Tmax>39(°). There was no significant correlation between fever and positive blood culture, urine culture, pneumonia, or surgical site infection. This information may help relieve stress for families and healthcare providers, and obviate routine laboratory evaluation for fever alone.

Measurement Variability in the Evaluation of the Proximal Junction in Distraction-based Growing Rods Patients.

Background: Proximal junctional kyphosis (PJK) is a known complication of spinal fusion and has been shown to occur in the setting of growing rod instrumentation. Previous studies have shown good reliability in measuring PJK in adolescent idiopathic scoliosis. Methods: Four pediatric orthopaedic spine surgeons measured the proximal junction in 10 patients with growing rod instrumentation using 2 methods. In method 1, measurements were made from the inferior endplate of the upper instrumented vertebrae (UIV) to the superior endplate of 1 level above the UIV. In method 2, measurements were made from the inferior endplate 2 levels below the UIV to the superior endplate 2 levels above the UIV. These measurements were repeated 1 week later. Results: Method 1 had an intraobserver variability of ±13.2 degrees and interobserver variability of ±21.6 degrees, whereas method 2 had an intraobserver variability of ±18.3 degrees and interobserver variability of ±20.7 degrees. Conclusions: Interobserver variability of PJK is >20 degrees. As PJK is commonly defined as >10 degrees of kyphosis above the UIV, measurement of PJK in patients with distraction-based growing rods on lateral radiographs has too much variability to be useful. Level of Evidence: Level III—diagnostic studies.

Continuing Delay in the Diagnosis of Slipped Capital Femoral Epiphysis

OBJECTIVE To evaluate whether the time from symptom onset to diagnosis of slipped capital femoral epiphysis (SCFE) has improved over a recent decade compared with reports of previous decades. STUDY DESIGN Retrospective review of 481 patients admitted with a diagnosis of SCFE at three large pediatric hospitals between January 2003 and December 2012. RESULTS The average time from symptom onset to diagnosis of SCFE was 17 weeks (range, 0-to 169). There were no significant differences in time from symptom onset to diagnosis across 2-year intervals of the 10-year study period (P = .94). The time from evaluation by first provider to diagnosis was significantly shorter for patients evaluated at an orthopedic clinic (mean, 0 weeks; range, 0-0 weeks) compared with patients evaluated by a primary care provider (mean, 4 weeks; range, 0-52 weeks; r = 0.24; P = .003) or at an emergency department (mean, 6 weeks, range, 0-104 weeks; r = 0.36; P = .008). Fifty-two patients (10.8%) developed a second SCFE after treatment of the first affected side. The time from the onset of symptoms to diagnosis for the second episode of SCFE was significantly shorter (r = 0.19; P < .001), with mean interval of 11 weeks (range, 0-104 weeks) from symptom onset to diagnosis. There were significantly more cases of mildly severe SCFE, as defined by the Wilson classification scheme, in second episodes of SCFE compared with first episodes of SCFE (OR, 4.44; P = .001). CONCLUSION Despite reports documenting a lag in time to the diagnosis of SCFE more than a decade ago, there has been no improvement in the speed of diagnosis. Decreases in both the time to diagnosis and the severity of findings for the second episode of SCFE suggest that the education of at-risk children and their families (or providers) may be of benefit in decreasing this delay.

Safety and Efficacy of Power-Assisted Pedicle Tract Preparation and Screw Placement.

STUDY DESIGN Retrospective review of 1 surgeons posterior spinal fusion cases. OBJECTIVES To assess the safety and efficacy of using power tools versus using manual tools to create pedicle tracts and place pedicle screws. SUMMARY OF BACKGROUND DATA This is the first study to report on the safety and efficacy of pedicle tract creation and pedicle screw placement using power tools. METHODS The study included 442 cases and 6412 pedicle screws. The manual tool cohort included 159 cases (1,870 screws, January 1, 2004 to June 30, 2007). The power tool cohort included 283 cases (4,542 screws, January 1, 2008 to August 29, 2012). Patient charts and radiographs were reviewed. The researchers recorded the number of screws placed and their positions. Screws were classified as failed if the patient returned to surgery for revision or removal of the screw. Operating and fluoroscopy times were analyzed by cohort overall and for diagnosis-specific subsets. RESULTS The incidence of injury resulting from pedicle screw placement was 0.00% (0 of 1,870) with the manual method and 0.02% (1 of 4,542) with power (p = .5211). One screw, placed with power, was assumed to have caused a minor hemothorax, which was successfully treated with a chest tube. There were no neurologic or vascular injuries or other complications attributable to a pedicle screw in either group. Screws placed with power were removed or revised because of problems attributable to the pedicle screw one-sixth as often as those placed using manual tools: 2 of 1,410 (0.14%) versus 8 of 948 (0.84%) (p = .024). Fluoroscopy times in the power cohort were two-thirds as long as those in the manual cohort (p < .001). Operating times were not significantly different (p = .109). CONCLUSIONS The use of power tools to create pedicle tracts and place pedicle screws was associated with shorter fluoroscopy times and a lower revision rate compared with using manual tools. Both techniques posed similar low risks of injury to the patient.

Functional characterization of the promoter for the mouse SPTLC2 gene, which encodes subunit 2 of serine palmitoyltransferase.

A series of luciferase reporter constructs was prepared from a 1035‐bp fragment of mouse genomic DNA flanking the 5′‐coding sequence for the SPTLC2 subunit of serine palmitoyltransferase, the initial enzyme of de novo sphingolipid biosynthesis. The full‐length DNA fragment promoted strong reporter gene expression in NIH3T3 cells while deletion and site‐directed mutagenesis indicated that the proximal 335 bp contain initiator and downstream promoter elements, two proximal GC boxes that appear to stimulate transcription in a cooperative manner, and several additional elements whose activity cannot be accounted for by known factor binding sites. These findings provide insight into the control mechanisms for transcription of mammalian SPTLC2.