Do Caregivers and Patients With Early-Onset Scoliosis Share the Same Perspective on Health-Related Quality of Life? A Comparison of 24-item Early-Onset Scoliosis Questionnaire and 22-item Scoliosis Research Society Questionnaire Scores.

OBJECTIVE: The 24-item Early-Onset Scoliosis Questionnaire (EOSQ-24) is validated in patients with early onset scoliosis (EOS) aged 0 to 18 years and the 22-item Scoliosis Research Society (SRS-22) questionnaire is validated in idiopathic scoliosis patients 10 years and older. EOSQ-24 is completed by the caregiver and SRS-22 is completed by the patient. A prior study comparing patient-reported outcome measures completed by older pediatric patients and their parents showed a low level of agreement. Our purpose was to compare EOSQ-24 and SRS-22 scores completed at the same time point and at subsequent time points, in patients aged 5 to 18 years with idiopathic or congenital EOS without developmental delay. METHODS: This was a multicenter retrospective study. We identified pairs of EOSQ-24 and SRS-22 completed on the same day or within 6 months. Some patients had multiple pairs of surveys over time. EOSQ-24 and SRS-22 questions were matched and domain scores for Pain, Function, Mental Health, and Satisfaction were compared. Patients with a change in treatment between surveys were excluded. Pearson correlation coefficients ( r ) were used to compare domain scores, with r ≥0.7 indicating a strong relationship. RESULTS: There were 228 patient-caregiver dyads who completed 411 pairs of EOSQ-24 and SRS-22 on the same day. A strong correlation was found only for the Pain domain ( r =0.77). Function, Mental Health, and Satisfaction domains had positive but not strong correlations ( r = 0.58, r = 0.50, r = 0.41, respectively). Subanalysis based on age also showed a strong correlation only for Pain. There were 76 patient-caregiver dyads who completed 134 pairs of surveys with SRS-22 completed within 6 months after an EOSQ-24. All domains demonstrated a positive but not strong correlation, with Pain showing the highest correlation ( r = 0.64). CONCLUSIONS: EOSQ-24 and SRS-22 had a strong correlation only for Pain when completed at the same time point. EOSQ-24 and SRS-22 completed within 6 months lacked a strong correlation for all domains. Our findings suggest that parents and children with EOS may not share the same perspective on their health. Self-reported questionnaires should be used when possible to assess health-related quality of life in older children and adolescents with EOS who are developmentally neurotypical. LEVEL OF EVIDENCE: Level III-diagnostic.

Skipped versus consecutive pedicle screw constructs for correction of Lenke 1 curves.

PURPOSE: Thoracic pedicle screws provide superior curve correction to hook and wire constructs in adolescent idiopathic scoliosis, while increasing cost. The number of implants required for best correction and outcome has not yet been determined. METHODS: We retrospectively reviewed pre- and post-operative radiographs and self-reported outcome measures in an age- and curve-matched cohort of 40 patients with Lenke I AIS who underwent selective fusions between T3/4 and L1. Twenty patients were treated with thoracic pedicle screws at every level bilaterally (CON) and 20 patients with screws at every level on the concave side and skipped levels on the convex side of the curve (SKP). All patients had a minimum 2-year follow-up. Radiographs were assessed for coronal and sagittal curvatures, as well as thoracic torsion and vertebral rotation. Health-related quality of life was assessed using the SRS-22 instrument. Instrumentation cost data were collected for each case. RESULTS: Postoperative follow-up averaged 28 months for the CON group and 29 months for the SKP group. No statistically significant differences were found between groups with respect to age and pre- and post-operative radiographic parameters. Both constructs provided acceptable correction of the main thoracic curves (66.9 vs. 66.6 %, CON group and SKP group, respectively; p = 0.92), and spontaneous correction of the proximal thoracic (41.5 vs. 41.1 %; p = 0.92) and thoracolumbar/lumbar curves (54.8 vs. 54.3 %; p = 0.92). No significant difference was found in postoperative SRS-22 scores (96 vs. 94.3; p = 0.34). The CON group cost for instrumentation was significantly higher than the SKP group ($19,500 vs. $13,300; p = 0.002). There was no statistically significant difference in operating room times between groups. CONCLUSION: Both construct types provide excellent coronal correction and sagittal balance, with no significant differences in radiographic findings or clinical outcomes. A significant decrease in cost was found with use of skipped screw constructs.

Association between structural rib autograft and the rate of arthrodesis in children undergoing occiput-C2 instrumentation and fusion.

OBJECTIVE: The purpose of this study was to identify factors associated with fusion success among pediatric patients undergoing occiput-C2 rigid instrumentation and fusion. METHODS: The Pediatric Spine Study Group registry was queried to identify patients ≤ 21 years of age who underwent occiput-C2 posterior spinal rigid instrumentation and fusion and had a 2-year minimum clinical and radiographic (postoperative lateral cervical radiograph or CT scan) follow-up. Fusion failure was defined clinically if a patient underwent hardware revision surgery > 30 days after the index procedure or radiographically by the presence of hardware failure or screw haloing on the most recent follow-up imaging study. Univariate comparisons and multivariable logistic regression analyses were subsequently performed. RESULTS: Seventy-six patients met inclusion criteria. The median age at surgery was 9 years (range 1.5-17.2 years), and 51% of the cohort was male. Overall, 75% of patients had syndromic (n = 41) or congenital (n = 15) etiologies, with the most frequent diagnoses of Down syndrome (28%), Chiari malformation (13%), and Klippel-Feil syndrome (12%). Data were available to determine if there was a fusion failure in 97% (74/76) of patients. Overall, 38% (28/74) of patients had fusion failure (95% CI 27%-50%). Univariate analysis demonstrated that use of a rigid cervical collar postoperatively (p = 0.04) and structural rib autograft (p = 0.02) were associated with successful fusion. Multivariable logistic regression analysis determined that patients who had rib autograft used in surgery had a 73% decrease in the odds of fusion failure (OR 0.27, 95% CI 0.09-0.82; p = 0.02). Age, etiology including Down syndrome, instrumentation type, unilateral instrumentation, use of recombinant human bone morphogenetic protein, and other variables did not influence the risk for fusion failure. CONCLUSIONS: In this multicenter, multidisciplinary, international registry of children undergoing occiput-C2 instrumentation and fusion, fusion failure was seen in 38% of patients, a higher rate than previously reported in the literature. The authors' data suggest that postoperative immobilization in a rigid cervical collar may be beneficial, and the use of structural rib autograft should be considered, as rib autograft was associated with a 75% higher chance of successful fusion.

Infection and revision strategies in total disc arthroplasty.

PURPOSE: Our aim was to revise the different strategies for treating an infected disc arthroplasty. METHODS: Despite recognition that disc replacement may reduce the incidence of adjacent-segment disease, the risk of potential complications associated with primary and revision total disc arthroplasty has diminished surgeon enthusiasm for the procedure. We performed a literature review of the different revision strategies for an infected disc arthroplasty. RESULTS: The need for revision of lumbar total disc arthroplasty has been reported in a number of prospective, randomised trials (level I or II evidence). Suboptimal patient selection and/or surgical technique accounted for the majority of failed disc arthroplasties. Revision procedures include posterior stabilisation or anterior extraction and conversion to arthrodesis. The risk of injury to the great vessels and retroperitoneal structures is greater during revision than primary procedures. The use of a distant lateral, or transpsoas, approach to the anterior column may reduce these adverse events. Also, the use of adhesion barriers has been shown to reduce adhesions in abdominal and pelvic surgery and may be of benefit in revision disc arthroplasty. CONCLUSION: This review article provides an update on the various treatments for infected lumbar disc prosthesis and the different surgical approaches used in these difficult cases. It also describes potential options to avoid complications associated with the revision surgical approach.

Postoperative spondilodiscitis.

INTRODUCTION: Postoperative spondylodiscitis is a primary infection of the nucleus pulposus with secondary involvement of the cartilaginous endplate and vertebral bone. Although uncommon, postoperative spondylodiscitis causes major morbidity and may be associated with serious long-term sequelae. Several risk factors had been identified, including immunosuppression, obesity, alcohol, smoking, diabetes and malnutrition. MATERIALS AND METHODS: A review of the literature was done to analyse the diagnosis, treatment and prevention of postoperative spondylodiscitis. RESULTS: We found that the principles of conservative treatment are to establish an accurate microbiological diagnosis, treat with appropriate antibiotics, immobilise the spine, and closely monitor for spinal instability and neurological deterioration. The purpose of surgical treatment is to obtain multiple cultures of bone and soft tissue, perform a thorough debridement of infected tissue, decompress neural structures, and reconstruct the unstable spinal column with bone graft with or without concomitant instrumentation. CONCLUSIONS: Appropriate management requires aggressive medical treatment and, at times, surgical intervention. If recognised early and treated appropriately, a full recovery can often be expected. Therefore, clinicians should be aware of the clinical presentation of such infections to improve patient outcome. A review of the literature was done to advance our understanding of the diagnosis, treatment, prevention and outcome of these infections.

Infections in spinal instrumentation.

Surgical-site infection (SSI) in the spine is a serious postoperative complication. Factors such as posterior surgical approach, arthrodesis, use of spinal instrumentation, age, obesity, diabetes, tobacco use, operating-room environment and estimated blood loss are well established in the literature to affect the risk of infection. Infection after spine surgery with instrumentation is becoming a common pathology. The reported infection rates range from 0.7% to 11.9%, depending on the diagnosis and complexity of the procedure. Besides operative factors, patient characteristics could also account for increased infection rates. These infections after instrumented spinal fusion are particularly difficult to manage due to the implanted, and possibly infected, instrumentation. Because the medical, economic and social costs of SSI after spinal instrumentation are enormous, any significant reduction in risks will pay dividends. The goal of this literature review was to analyse risk factors, causative organisms, diagnostic elements (both clinical and biological), different treatment options and their efficiency and consequences and the means of SSI prevention.

The effect of end screw orientation on the stability of anterior instrumentation in cyclic lateral bending.

BACKGROUND CONTEXT: Screw pullout at the proximal or distal end of multilevel anterior instrumentation can occur clinically. Previous laboratory studies have shown that angulation of vertebral body screws increases screw pullout strength and stability in toggling. PURPOSE: To determine the effect of end screw angulation on instrumentation construct stability after cyclic, lateral bending. STUDY DESIGN: A biomechanical study in calf spines comparing two anterior spinal instrumentation constructs, one with parallel polyaxial screws and the other with angled polyaxial end screws. METHODS: Sixteen instrumented constructs were made from eight thoracic (T8-T12) and eight lumbar calf spines (L1-L5). Eight (four lumbar specimens and four thoracic specimens) had five bicortical screws inserted mid-body and parallel to the end plates. The other eight specimens had two screws angled toward the superior end plates of the top two vertebrae; the middle vertebra had a mid-body screw parallel to the end plate, and the bottom two vertebrae had screws angled towards their inferior end plates. The constructs were then cycled in lateral bending, and the displacements of the two instrumentations with a 10 N-m bending load were compared. RESULTS: After 10,000 cycles, constructs with parallel end screws exhibited twice the average displacement than those with angled screws: 5.4 mm versus 2.9 mm (p=.031). CONCLUSION: The use of angled screws at the ends of anterior constructs demonstrated increased construct stability after cycling compared with traditional transverse screws. Although angled screw insertion is technically more difficult and is possible only with specific screw designs, its use might increase instrumentation longevity.

Partial facetectomy for lumbar foraminal stenosis.

Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57%) reported no back pain and no functional limitations. Eight of 47 patients (17%) reported moderate pain, but had no limitations. Six of 47 patients (13%) continued to experience degenerative symptoms. Five of 47 patients (11%) required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability.

Using triggered electromyographic threshold in the intercostal muscles to evaluate the accuracy of upper thoracic pedicle screw placement (T3-T6).

STUDY DESIGN: A prospective clinical study of high thoracic pedicle screws monitored with triggered electromyographic (EMG) testing. OBJECTIVE: To evaluate the sensitivity of recording intercostal muscle potentials to assess upper thoracic screw placement. SUMMARY OF BACKGROUND DATA: Triggered EMG testing from rectus muscle recordings, which are innervated from T6 to T12, has identified medially placed thoracic pedicle screws. No clinical study has correlated an identical technique with the intercostal muscle for upper pedicle screws placed in the upper thoracic spine (T3-T6). METHODS: A total of 311 high thoracic screws were placed in 50 consecutive patients. Screws were placed from T3 to T6 and were evaluated using an ascending method of stimulation until a compound muscle action potential was obtained from the intercostal muscles. Screw position was then evaluated using computed tomography and results were compared with evoked EMG threshold values. RESULTS: Fifteen screws (5%) showed penetration on postoperative computed tomography scans. Eleven screws showed medial cortical breakthrough (3.6%), 6 had stimulation thresholds 20 mA. Of the 296 screws with thresholds between 6 and 20 mA, 285 (91%) were within the vertebra. No postoperative neurologic complications were noted in any of the 50 patients. CONCLUSION: In this series, cortical violation is highly unlikely in patients whose stimulation threshold lies between 6 and 20 mA with values 60% to 65% decreased from the mean (98% negative predictive value). Although verification of screw placement should not depend solely on stimulation thresholds, pedicle screw stimulation provides rapid and useful intraoperative information on screw placement during procedures involving the use of thoracic pedicle screws.

Comparing the clinical and radiological outcomes of pedicular transvertebral screw fixation of the lumbosacral spine in spondylolisthesis versus unilateral transforaminal lumbar interbody fusion (TLIF) with posterior fixation using anterior cages.

STUDY DESIGN: This study retrospectively compares the clinical and radiologic outcomes of unilateral transforaminal lumbar interbody fusion (TLIF) with those of transvertebral screw fixation of the lumbosacral spine in high-grade spondylolisthesis. OBJECTIVE: To examine the outcome and perioperative complications of unilateral TLIF and compare those results with Transvertebral Screw Fixation in the treatment of high-grade spondylolisthesis. SUMMARY OF BACKGROUND DATA: High-grade spondylolisthesis has been associated with a high complication and failure rate regardless of the method of treatment. We compare 2 techniques to improve success rates. METHODS: Forty patients were divided into 2 groups: group A, unilateral TLIF, and group B, transacral screws. The mean age was 33 years (range, 19-48 years), and the mean follow-up was 35 months (range, 24-48 months). The mean grade of spondylolisthesis measured by Meyerding grading was 3.6 (range, 3-5). A Scoliosis Research Society outcome score was obtained on all patients. Fusion was determined by both radiograph and computed tomography scan. RESULTS: Group A: 100% fusion. The slip angle improved from 38.6 degrees (range, 24-78 degrees ) before surgery to 23.8 degrees (range, 12-38 degrees ) after surgery. Group B: 95% of patients evidenced solid fusion by the 6-month follow-up. The slip angle, improved from 38.2 degrees (range, 22-78 degrees ) before surgery to 23 degrees (range, 9-36 degrees ) after surgery. There was no significant improvement in the percentage slip or the sacral inclination in any of the groups. COMPLICATIONS: A: 7 unintended durotomies and 3 wound infections. B: 1 unintended durotomy, 1 pseudarthrosis, 2 wound infections, and 1 implant failure. There were no neurologic complications in any of the groups. The Scoliosis Research Society outcome instrument demonstrated good postoperative pain control, function, self-image, and satisfaction in both groups. CONCLUSION: No significant differences in radiologic and clinical outcome were found, in either group. Both procedures appear to be safe and effective surgically and radiographically.