Spinal dysraphism in congenital scoliosis and kyphosis: a retrospective analysis in an Indian population.

PURPOSE: Early recognition is crucial for occult spinal dysraphism associated with congenital spinal deformities. There is limited literature available on its occurrence in congenital scoliosis and kyphosis in the Indian population. METHODS: Our study involved a retrospective review of 247 children who presented at a single centre. We analyzed their demographics and clinical and radiological findings, which included the type of deformity, its location, vertebral anomaly, Cobb angle, and MRI findings. The deformities were categorized as congenital scoliosis or congenital kyphosis with failure of formation, failure of segmentation, or both. RESULTS: A total of 247 cases were examined (congenital scoliosis-229, congenital kyphosis-18). The average age was seven years (range 0.8 to 19 years, SD 4.6). The mean Cobb angle at presentation in the congenital scoliosis group was 49.4° (range 8 to 145°, SD 23.77) for those with abnormal MRI and 42.45° (range 5 to 97°, SD 20.09) for those with normal MRI. For the congenital kyphosis group, the mean K angle at presentation was 47.7° (range 14 to 110°, SD 33.33) for those with abnormal MRI and 47.36° (range 15 to 70°, SD 16.63) for those with normal MRI. Abnormal MRI results were observed in 130 of the patients (congenital scoliosis-53.7%, congenital kyphosis-38.8%). The highest incidence of abnormal MRI findings was observed in the failure of segmentation (66.6%) and mixed (65%) types. Deformities in the dorsal region had the highest incidence (61.9%). The most common dysraphism instances were diastematomyelia and tethered cord. There was a significant correlation between type of deformity and presence of dysraphism. CONCLUSION: This is the largest case series of congenital scoliosis and kyphosis reported from India. We found a high incidence of occult spinal dysraphism as compared to other published series. Occult spinal dysraphism is more common in the thoracic region. Diastematomyelia followed by tethered cord was the most common anomaly observed. We recommend MRI screening of whole spine and craniovertebral junction.

Tuberculosis of the spine in children - does drug resistance affect surgical outcomes?

BACKGROUND CONTEXT: The emergence of drug resistance has complicated the management of spinal tuberculosis (TB). While it is well known that the medical management of drug-resistant spinal TB is more difficult, the surgical outcomes of the same have not been studied sufficiently, particularly in children. PURPOSE: To analyze the surgical outcomes in a cohort of children treated for spinal TB, and to thus assess whether drug resistant (DR) disease is associated with poorer surgical outcomes. STUDY DESIGN/SETTING: Retrospective observational study. PATIENT SAMPLE: All children diagnosed and treated for tuberculous spondylodiscitis at a single center between January 2014 and June 2017. OUTCOME MEASURES: Surgical outcomes in terms of neurological status and kyphosis angle at final follow-up, and complication rates. METHODS: Radiographic and clinical data of children treated for spinal TB with minimum two-year follow-up were retrospectively analyzed. Data gathered included age, gender, level of spine affected, number of vertebrae involved, neurology (Frankel grade), microbiological reports, duration and type of anti-tuberculous therapy (ATT), details of Orthopaedic management and complications during treatment. In DR cases, the time from presentation to starting of second-line ATT was also assessed. Radiographs were reviewed to note the pre- and post-operative degree of kyphosis as well as the angle at final follow-up. Patients that developed major complications were compared statistically with those that did not. RESULTS: Forty-one consecutive children (mean age 8.5 ± 4.2 years, 20 boys, 21 girls) were treated for spinal TB with a mean follow-up of 31.2 ± 6.4 months. Fifteen were managed conservatively, of which only one had DR-TB. Of the 26 managed surgically, 13 were managed with first-line ATT and 13 required second-line ATT. Of this latter group, eight had microbiologically proven drug resistance, whereas five were switched to second-line therapy presumptively because of failure to show an adequate response to first-line regimen. At last follow-up, all children had completed the prescribed course of ATT and had been declared cured. Neurological improvement was seen in all but one patient; and at last follow-up, 18 children were Frankel E, seven were Frankel D, and one was Frankel B. 1The immediate post-operative Kyphosis angle averaged 24.38° ± 15.21°. However, six children showed a subsequent worsening of kyphosis, and the Kyphosis angle at last follow-up averaged 30.96° ± 23.92°. Five children had major complications requiring revision surgery; complications included wound dehiscence, vertebral collapse, screw pull-out and implant breakage. Significantly higher number of patients in the group with complications had required second-line ATT (p < .05). CONCLUSIONS: In a cohort of children treated surgically for spinal tuberculosis, a higher complication rate, and thus poor surgical outcomes, were found to be associated with drug resistant disease.

Delayed Treatment of a Traumatic Lumbosacral Dislocation With Associated Injuries: A Case Report.

CASE: A 41-year-old woman sustained a degloving injury over her lumbosacral and perineal region with fractures of her right tibia and fibula. After diversion colostomy and osteosynthesis for the fractures at a primary center, a missed grade 2 lumbosacral dislocation was diagnosed at a tertiary center and the degloving injury was treated with debridement and skin grafting. After 5 months, the dislocation had progressed to grade 4 and she underwent delayed posterior lumbosacral reduction, interbody fusion, and L4-S1 fixation, with superior gluteal artery perforator flap and subsequent colostomy closure, with good outcomes (Oswestry Disability Index 10%) at the 3-year follow-up. CONCLUSION: A rare, missed, progressive traumatic L5-S1 spondylolisthesis with associated injuries is described.

Skeletal Fluorosis With Thoracic Myelopathy: A Report of 2 Cases.

BACKGROUND: To report 2 different presentations of thoracic myelopathy with ossification of ligamantum flavum (OLF) due to fluorosis. METHODS: Two females presented with thoracic myelopathy secondary to spinal stenosis with OLF due to fluorosis. On examination, the first patient had a grade 4 power in both lower limbs with altered sensation below L1 dermatome. She had segmental OLF on magnetic resonance imaging and computed tomography and was treated with posterior thoracic laminectomy and recovered well. The second patient had a history of a prior thoracic laminectomy at another institution and presented with paraplegia with bladder involvement. Radiological investigations revealed a 3-column injury at the level of D8/D9. This patient was treated with decompression and stabilization. RESULTS: The first patient recovered neurologically and regained independent ambulation while the second patient had a reduction in spasticity but no recovery of power or bladder function. CONCLUSION: Different presentations and causes of myelopathy due to OLF should be recognized and treated. An unstable injury is very rare and should not be missed.

Transoral release to realign postoperative loss of reduction following occipitocervical fixation for congenital basilar invagination.

PURPOSE: Revision surgery in an irreducible atlantoaxial dislocation (IAAD) previously operated with a posterior approach is challenging. Multiple modalities using anterior, posterior, and dual approaches have been described. We report a so far unreported technique of revision surgery by posterior implant removal and decompression with anterior transoral release followed by posterior instrumentation. METHODS: 14-year male with basilar invagination (BI) with IAAD, previously operated with posterior decompression and instrumented occipitocervical fusion presented three months later with post-traumatic recurrence of myelopathy with quadriparesis with Di Lorenzo grade 4 and loss of reduction. He was operated with a posterior implant and early fusion mass removal with extended foramen magnum decompression (FMD), followed by anterior transoral release with a satisfactory reduction on traction, and finally, a posterior revision instrumented occipitocervical fusion. RESULTS: At 2-year follow-up, the patient was symptom-free with Di Lorenzo grade 1 and cervicomedullary angle improvement from 97.4° to 141.2°; achieving bony fusion. CONCLUSION: Single-stage posterior-anterior transoral-posterior approach can be used to achieve satisfactory reduction for a revision BI with IAAD with prior posterior instrumentation.

Posterior Circulation Stroke due to Atlantoaxial Instability in CHST3-Related Skeletal Dysplasia: A Case Report.

CASE: An eight-year-old boy presented with acute encephalopathy due to posterior circulation ischemic stroke. He was found to have vertebral artery stenosis secondary to atlantoaxial instability (AAI) due to an os odontoideum. Occipitocervical fusion was performed 4 weeks after stroke. The child improved neurologically and regained independent ambulation. He had indications of an underlying spondyloepiphyseal dysplasia with joint luxation and whole-exome sequencing diagnosed CHST3-related skeletal dysplasia. CONCLUSION: As far as we know, this AAI due to an os odontoideum is a previously unreported complication of CHST3-related skeletal dysplasia. Occipitocervical fusion yielded good clinical results with the 1-year follow-up.

Assessment of pedicle screw malposition in uniplanar versus multiplanar spinal deformities in children.

BACKGROUND: Spinal deformities can either be uniplanar or multiplanar. The current study aims to compare mal-positioned pedicle screw assessment on radiographs versus CT in children <12 years with multiplanar and uniplanar spinal deformities. METHODS: A cohort of 15 children, mean age 10.1 years, who underwent posterior spinal fusion using free-hand pedicle screw insertion for multiplanar (M) or uniplanar (U) deformities with post-operative radiograph and CT evaluation of 154 screws. The outcome measures included the assessment of malpositions detected on plain radiographs versus CT scans in U and M deformities. The overall breaches in post-operative plain radiographs and CT in each group were compared and analyzed by two independent observers.The mal-positioned screws were graded on extent of cortical breach on CT. Inter and intra-observer variability was calculated with Kappa(k) method. Sensitivity, Specificity and Positive Predictive Value (PPV) and Negative Predictive Value (NPV) were calculated by comparing breaches on radiographs versus CT considered the gold standard. RESULTS: In total,154 pedicle screws were analyzed, 65 in U group and 89 in M group. There were 23 (14.9%) malpositioned screws identified on plain radiographs and 43 (27.9%) on CT (p = 0.008). There were 17/154 (11.03%) Grade 1 breaches, 16/154 (10.38%) Grade 2 breaches and 10/154(6.49%) Grade III breaches.Among the 43 CT breaches, 12/65 (18.46%) were in U group, 31/89 (34.83%) were in M group (p = 0.013).The overall Sensitivity, Specificity and PPV of plain radiographs compared to CT in detecting malpositions were 32.56%, 91.89% and 60.87% respectively. CONCLUSIONS: There was a significant discrepancy in identification of pedicle screw malposition based on plain radiographic versus CT based assessment, more so in multiplanar deformities. The ability to detect a breach on plain radiographs is lesser in multiplanar versus uniplanar deformities.

The technique of using three-dimensional and multiplanar reformatted computed tomography for preoperative planning in pediatric craniovertebral anomalies.

BACKGROUND: Computed tomography (CT) images provided by the radiology department may be inadequate for planning screws for rigid craniovertebral junction (CVJ) instrumentation. Although many recommend using multiplanar reconstruction (MPR) in line with screw trajectories, this is not always available to all surgeons. The current study aims to present a step-by-step workflow for preoperative planning for pediatric CVJ anomalies. METHODS: Twenty-five consecutive children (<12 years) were operated for atlantoaxial instability between 2014 and 2019. Preoperative CT angiograms were transferred to an open-source software called Horos™. The surgeon manipulated images in this viewing software to determine an idealized path of screws. Three-dimensional volume rendering of the pathoanatomy was generated, and anomalies were noted. The surgeon compared the anatomical data obtained using Horos™ with that from the original imaging platform and graded it as; Grade A (substantial new information), Grade B (confirmatory with improved visualization and understanding), Grade C (no added information). The surgeon then executed the surgical plan determined using Horos™. RESULTS: Surgeries performed were occipitocervical (n = 18, 72%) and atlantoaxial fixation (n = 7, 28%) at a mean age of 7.2 years, with 72% of etiologies being congenital or dysplasias. In 18 (72%) patients, the surgeon noted substantial new information (Grade A) about CVJ anomalies on Horos™ compared to original imaging platform. Concerning planning for fixation anchors, the surgeon graded A in all patients (100%). In 4 (16%) patients, the surgery could not be executed precisely as planned. There were three (12%) complications; VA injury (n = 1), neurological worsening (n = 1), and loss of fixation (n = 1). CONCLUSION: In our experience, surgeon-directed imaging manipulation gives more anatomical information compared to studying original imaging planes and should be incorporated in the surgeon's preoperative workup. When image reformatting options are limited, open-source software like Horos™ may offer advantages.

Cervical myelopathy in a child with Sprengel shoulder and Klippel-Feil syndrome.

PURPOSE: Sprengel shoulder, Klippel-Feil syndrome and congenital scoliosis are associated conditions. Cervical myelopathy in a child due to a concomitant omovertebral bar causing posterior cord compression and a hypermobile cervical disc protrusion adjacent to fused cervical segments causing anterior compression at the same level is very rare. We report the presentation, findings, surgical management and results of treatment in such a child. METHODS: A 9-year-old girl with Sprengel shoulder presented with cervical myelopathy (Frankel D). Imaging revealed a bony omovertebral bar connected to the left scapula compressing the spinal cord posteriorly through a lamina defect at C5 resulting in significant cervical stenosis. A hypermobile disc protrusion adjacent to congenitally fused segments resulted in anterior compression at the same level. She was treated surgically with cervical laminectomy and instrumented fusion, excision of the omovertebral bar and modified Woodward procedure for the left Sprengel shoulder. RESULTS: At 2 year follow-up, she had improved neurologically (Frankel E) and there was improved shoulder symmetry and abduction. MRI showed resolution of cervical stenosis. Although there was no significant progression of congenital scoliosis, it will need to be monitored. CONCLUSIONS: Cervical myelopathy due to an omovertebral bar and cervical disc protrusion in a child with Klippel-Feil syndrome and Sprengel shoulder is a rare presentation and can be treated with a single posterior approach addressing both pathologies.

Spinal Epidural Lipomatosis with Osteoporotic Vertebral Fractures Presenting as Acute Thoracic Myelopathy in a 33-Year-Old Man with Cushing Disease.

BACKGROUND: Steroid-related spinal epidural lipomatosis (SEL) is a well-known condition most commonly encountered in patients taking chronic steroid medications. Endogenous Cushing syndrome is a rare cause of SEL. The authors report an unusual presentation of acute thoracic myelopathy due to SEL with osteoporotic vertebral compression fractures in a patient with Cushing disease. CASE DESCRIPTION: A 33-year-old man presented with thoracic myelopathy due to SEL and multiple vertebral compression fractures. He had Cushingoid clinical features, and investigations revealed a pituitary microadenoma as the cause of hypercortisolism. The diagnosis was missed on multiple occasions before the onset of paraparesis. The patient was treated with urgent thoracic laminoplasty followed by transsphenoidal surgery on the same day. Although normalization of the serum cortisol levels was delayed by 6 months, he had a complete neurologic recovery and remains symptom free at 2 years follow-up. CONCLUSIONS: This is a rare presentation of Cushing disease and has been reported only twice before in the 1990s. This case highlights the need to keep a high degree of suspicion for development of thoracic myelopathy in a patient with Cushing syndrome who develops thoracic compression fractures associated with SEL. Early recognition of this clinical association and addressing the primary endocrine problem urgently could have prevented spinal cord involvement and the subsequent spine surgery. This scenario is also documented in previous published case reports of this association where the diagnosis of Cushing syndrome has been revealed retrospectively after the development of neurologic symptoms.

Emergency and Urgent Orthopaedic Surgeries in non-covid patients during the COVID 19 pandemic: Perspective from India.

OBJECTIVES: To Evaluate the results and the protocols of our Institution for 18 Emergency and Urgent Non Covid Surgeries during the Covid 19 Pandemic. METHODS: 18 patients underwent Emergency and Urgent Orthopaedic Surgeries at institution. The Protocol was Screening, Segregation, Selection, Isolation, theatre modification, and Online Follow. RESULTS: Two adverse events including, one death and one intensive care admission due to underlying morbidity were recorded. Average Hospital stay was 2.5 days with no patients becoming covid positive at follow up. CONCLUSION: Strict Surgical protocols need to be followed for surgery during the Covid19 pandemic.

Short Term Results of a New Comprehensive Protocol for the Management of Congenital Pseudarthrosis of the Tibia.

BACKGROUND: Treatment of Congenital Psuedarthrosis of Tibia (CPT) often poses significant challenges due to difficulty in achieving union and subsequent complications like refractures, implant failures, etc. Our new comprehensive protocol is aimed at achieving crossunion between the tibia and fibula. AIMS AND OBJECTIVES: The aim of the present study is to evaluate the short-term results of our new protocol and to compare the results with our previously used techniques. MATERIALS AND METHODS: 10 patients with mean age 2.35 years (1 to 6.5 years) who were treated by our new comprehensive protocol were included in Group A, and 11 patients with mean age 2 years (1 to 5.5 years) who primarily underwent intramedullary rodding with bone graft were included in Group B. The new comprehensive protocol consisted of pre-operative Zolendronate infusion, surgery consisting of intramedullary fixation of tibia supplemented with Ilizarov ring fixator and bone grafting aimed at achieving tibia-fibula cross-union. Retrospective evaluation of serial radiographs was performed and outcomes with respect to union and subsequent complications were analysed. RESULTS: 10/10 (100%) patients in Group A united, whereas union was achieved in only 8/11 (72%) patients in Group B. The index surgery was successful in achieving union in all 10 patients in Group A, whereas in Group B 2.25 (1 to 4) surgeries were needed to achieve union. The time to union was significantly shorter in Group A (4.68 months) as compared to Group B (30.88 months). The cross sectional area of union was significantly greater in Group A (3.82 cm2) as compared to Group B (1.18 cm2). One patient in Group A needed a subsequent corrective osteotomy for tibial valgus, and one patient underwent tibia lengthening; whereas in Group B, two patients needed corrective osteotomes for residual malaligments. CONCLUSION: Our study demonstrates that the new comprehensive protocol is extremely effective for achieving sound union in Congenital Pseudarthrosis of Tibia.

Coxa vara in postseptic arthritis of the hip in children.

The behavior and treatment of coxa vara and pseudarthrosis of the proximal femur secondary to sepsis is not well described. The aim of this study is to describe the pathoanatomy for coxa vara and pseudarthrosis in postseptic hips, evaluate progression of neck shaft angle (NSA), and discuss treatment. This is a retrospective case series of 20 patients (21 hips). There were 11 hips with predominant avascular necrosis of the capital femoral epiphysis without pseudarthrosis (type 1) and 10 with pseudarthrosis (type 2). The interobserver κ value was 0.79. There was a decrease in NSA from 110.3° to 99.3° during an average follow-up duration of 5.2 years (range: 2-14 years). The average change in NSA between the initial presentation and the final follow-up was 5.5° in type 1 and 17.1° in type 2. Nine patients underwent a surgical intervention. In cases where subtrochanteric valgus osteotomy was performed, the mean preoperative NSA was 94° and the mean NSA at the final follow-up was 128°; all operated pseudarthroses healed without bone grafting. Acetabuloplasty is not necessary in most cases.

Is a Persistent Vacuum Phenomenon a Sign of Pseudarthrosis After Posterolateral Spinal Fusion?

The purpose of this study is to evaluate whether the vacuum phenomenon (VP) resolves after posterolateral lumbar fusion, and whether persistence of VP is indicative of failed fusion. We retrospectively reviewed patients with degenerative lumbar spinal stenosis with instability with a positive VP on preoperative computed tomography (CT) who underwent posterolateral lumbar spinal fusion. Lumbar CT and radiographs were evaluated for the presence of VP and fusion at each level. Thirty-six positive VP levels were identified on the preoperative lumbar CT at the levels in the fusion in 18 patients. The mean age at surgery was 67.6 ± 9.4 years and mean follow-up was 1.6 ± 0.86 years. Fusion was seen at 32 levels (88.9%). Of the 15 levels where VP persisted, evidence of fusion was seen in 13 levels and pseudarthrosis was seen at 2. Of the 21 levels where VP disappeared, fusion was seen at 19 levels and pseudarthrosis was seen at 2 .There was no significant difference between the 2 groups (P > .05). We did not find an association between persistence of VP and pseudarthrosis. Persistence of VP after spinal fusion may not be an indicator of pseudarthrosis, and should not be misinterpreted as an indication for additional surgery.

The effect of serial growing rod lengthening on the sagittal profile and pelvic parameters in early-onset scoliosis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To report the effect of repeated growing rod (GR) lengthenings on the sagittal and pelvic profile in patients with early-onset scoliosis. SUMMARY OF BACKGROUND DATA: Posterior distraction-based GRs have gained popularity as a technique for the surgical management of early-onset scoliosis. However, there are no published studies on the effect of serial GR lengthenings on sagittal balance, thoracic kyphosis (TK), lumbar lordosis (LL), and pelvic parameters. METHODS: We retrospectively reviewed data from a multicenter early-onset scoliosis database. Forty-three patients who were able to walk with minimum 2-year follow-up who underwent single- or dual-GR surgery were included for review. Mean number of lengthenings was 6.4 (range, 3-16). Mean preoperative age was 5.6 years (standard deviation, 2.4 yr), and mean follow-up was 3.5 years. Maximum TK, LL, and sagittal balance were assessed preoperatively, after index surgery, and at the latest follow-up. RESULTS: There was a significant decrease both in TK and LL after index surgery, which then increased during the lengthening period. There was a significant increase in both proximal junctional kyphosis and distal junctional angle. Pelvic parameters (pelvic tilt, pelvic incidence, sacral slope) were unchanged during the treatment period. Significant improvement was observed in sagittal balance. There was a correlation between the change in TK and change in LL. CONCLUSION: TK decreased after index surgery and increased between the index surgery and the latest follow-up, which was accompanied by an increase in LL. All-screw proximal constructs had mean 9° more proximal junctional kyphosis than all-hook proximal constructs. An increase in proximal junctional kyphosis and distal junctional angle was found during the treatment period. Although there was an independent effect of number of lengthenings on TK, there was no significant detrimental effect on other sagittal spinopelvic parameters. GRs had a positive effect on sagittal vertical axis, which returned patients to a more neutral alignment through the course of treatment. LEVEL OF EVIDENCE: 4.

Sacrectomy and adjuvant radiotherapy for the treatment of sacral chordomas: a single-center experience over 27 years.

STUDY DESIGN: Retrospective cohort (case only). OBJECTIVE: To evaluate the results and survival determinants of 21 patients with sacral chordomas treated with en bloc resection and adjuvant radiotherapy. SUMMARY OF BACKGROUND DATA: There are few long-term studies on treatment of sacral chordomas with more than 20 patients, and factors related to survival are not fully understood. METHODS: Demographics, treatment, complications, and oncological outcomes were analyzed with summary statistics, hypothesis testing with Mantel-Haenszel-Cox analysis, log-rank test, Cox proportional hazard model, and Kaplan-Meier survival estimates as applicable. RESULTS: There were 12 males and 9 females with mean age of 61 years (16-79) and mean follow-up of 5.8 years (2-19.2). Tumor stage was IB in 20 and IIIB in one; mean tumor size was 10.5 cm. Fourteen patients underwent combined anterior-posterior resection and 7 posterior resection alone; 18 received adjuvant radiotherapy. After treatment, bowel and bladder control were present in 4 and 5 patients, respectively. Complications included: wound infection (4), other wound complications (9), fistula (2), deep vein thrombosis (1), and pulmonary embolism (1). Median survival was 7.2 years. Eight (40%) had local recurrence and 4 (19%) metastatic disease. Mean disease-free interval before recurrence was 2.5 years (1-5). No patient (n = 8) treated in the past 9 years has had local or distant disease. Patients treated for recurrent tumor survived 5.7 years on average (range, 0.8-9) after the first recurrence. The only risk factor for tumor recurrence was proximal tumor extent (P = 0.05) There was a statistically significant association between recurrence and survival (RR = 3.8; 95% confidence interval, 1.0-15.3; P = 0.04). CONCLUSION: Despite the complications, increased long-term survival can be achieved with treatment. Proximal tumor extent may be related to recurrence and survival. Recurrence rates have diminished over time, emphasizing the importance of an experienced multidisciplinary surgical team. LEVEL OF EVIDENCE: N/A.

Citation classics in pediatric orthopaedics.

BACKGROUND: The purpose of this study was to identify the clinical pediatric orthopaedic articles with at least 100 citations published in all orthopaedic journals and to examine their characteristics. METHODS: All journals dedicated to orthopaedics and its subspecialties were selected from the Journal Citation Report 2001 under the subject category "orthopedics." Articles cited 100 times or more were identified using the database of the Science Citation Index Expanded (SCI-EXPANDED, 1900 to present). The articles were ranked in a comprehensive list. Two authors independently reviewed the full text of each article and applied the inclusion and exclusion criteria to the list of articles. The 2 lists were then compared. All disagreements were resolved by consensus with input from the senior author. The final list of pediatric orthopaedic articles was then compiled. RESULTS: There were a total of 49 journals under the search category "orthopedics." Five journals were excluded as they were non-English journals. The remaining 44 journals were screened for articles with at least 100 citations. A total of 135 clinical pediatric orthopaedic articles cited at least 100 times were included. The most cited article was cited 692 times. The mean number of citations per article was 159 (95% confidence interval, 145-173). All the articles were published between 1949 and 2001, with 1980 and 1989 producing the most citation classics (34). The majority (90) originated from the United States, followed by the United Kingdom (12) and Canada (11). Scoliosis/kyphosis was the most common topic with 26 papers. The second most common subject was hip disorders (24). Therapeutic studies were the most common study type (71). Ninety-seven papers were assigned a 4 for level of evidence. CONCLUSIONS: The list of citation classics in pediatric orthopaedic articles is useful for several reasons. It identifies important contributions to the field of pediatric orthopaedics and their originators; it facilitates the understanding and discourse of modern pediatric orthopaedic history and reveals trends in pediatric orthopaedics.

Effectiveness of cross-linking posterior segmental instrumentation in adolescent idiopathic scoliosis: a 2-year follow-up comparative study.

BACKGROUND CONTEXT: Surgeons continue to debate the need for a cross-link (CL) in posterior spinal instrumentation constructs with segmental pedicle screws in adolescent idiopathic scoliosis (AIS). Advantage of CLs is increased stiffness of the construct, and disadvantages include added expense and risk of late operative-site pain and pseudarthrosis. PURPOSE: To compare the effectiveness of using CLs versus using no cross-links (NCLs) in posterior segmental instrumentation in AIS. STUDY DESIGN: Retrospective comparative study, level of evidence 3. PATIENT SAMPLE: Seventy-five AIS patients less than 21 years of age, who underwent posterior spinal instrumentation with segmental pedicle screws (25 with CLs and 50 with NCLs) at a single institution with 2-year follow-up, are described. OUTCOME MEASURES: Physiologic measures include imaging: thoracic and lumbar Cobb angles, correction rate, apical vertebral translation (AVT), and apical vertebral rotation (AVR); self-report measures include Scoliosis Research Society (SRS) domain outcome scores. METHODS: Preoperative (pre-op) and postoperative first erect, 1-year, and 2-year follow-up radiographs were measured. Instrumentation-related complications and normalized SRS scores were recorded. Independent sample t test, χ(2) test, and repeated-measures analysis of variance were used for analyses. RESULTS: The average age at surgery was 14 years, the mean pre-op Cobb angle was 57°, and the mean number of levels fused was 10.9. The groups were similar preoperatively with respect to age, sex, Lenke curve, Cobb angle, AVT, and Risser grade and were similar intraoperatively for levels fused and anchor density. There was no difference in AVR, Cobb angle, correction rate, or AVT between the groups (p>.05). Complications included one wound infection in the CL group and one painful scar in the NCL group. There were no differences in SRS domain scores. CONCLUSION: We observed no differences in maintenance of correction, SRS scores, and complications with or without cross-linking posterior segmental instrumentation in AIS patients over 2-year follow-up. Further follow-up is necessary.

Gait pattern and lower extremity alignment in children with Morquio syndrome.

The gait in children with Morquio syndrome (MPS IV) has not been previously described. We reviewed the charts, gait analysis reports, and radiographs of nine children with no previous lower extremity surgery. Children with MPS IV had a slower walking speed, reduced cadence, and reduced stride length as compared with normal (P<0.05). There was increased knee flexion, genu valgus, and external tibial torsion during stance (P<0.05). Kinetics showed that knee varus moment was increased (P<0.05). There was a strong correlation between genu valgus measured on gait analysis and standing radiographs (r=0.89).