Approaching Spine Research in an Outreach Setting: What Type of Infrastructure is Conducive for Conducting Research?

Organizing medical research in an outreach setting can be a challenging task, especially when it involves complex spine procedures in patients whom it is difficult to follow-up for long term. Disease severity at presentation is often advanced in outreach settings due to limited local resources, surgeon expertise, and hospital infrastructure. Case complexity can present a challenge to local and outreach surgeons alike. This article will describe what encompasses an ideal outreach program as it relates to spine, how to manage cost in an outreach setting, collection of outcome data, and maintaining long-term follow-up. As one of the criticisms of medical outreach is the relative paucity of outcome data, this article discusses methods to collect and report outcomes abroad. We also discuss the value of translating outcome questionnaires to different languages and cross-cultural comparisons. In addition, relatively rare pathologies are often seen with greater frequency abroad. These patients are ideally suited for a focused case series than can guide treatment decisions.

Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures.

The Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures evidence-based clinical practice guideline was codeveloped by the American Academy of Orthopaedic Surgeons (AAOS) and the American Dental Association. This guideline replaces the previous AAOS Information Statement, "Antibiotic Prophylaxis in Bacteremia in Patients With Joint Replacement," published in 2009. Based on the best current evidence and a systematic review of published studies, three recommendations have been created to guide clinical practice in the prevention of orthopaedic implant infections in patients undergoing dental procedures. The first recommendation is graded as Limited; this recommendation proposes that the practitioner consider changing the long-standing practice of routinely prescribing prophylactic antibiotic for patients with orthopaedic implants who undergo dental procedures. The second, graded as Inconclusive, addresses the use of oral topical antimicrobials in the prevention of periprosthetic joint infections. The third recommendation, a Consensus statement, addresses the maintenance of good oral hygiene.

Anterior Dual Rod Versus Posterior Pedicle Fixation Surgery for the Surgical Treatment in Lenke 5C Adolescent Idiopathic Scoliosis: A Multicenter, Matched Case Analysis of 42 Patients.

STUDY DESIGN: Multicenter matched case analysis. OBJECTIVE: Compare patients with Lenke 5C scoliosis surgically treated with anterior spinal fusion with dual rod instrumentation and anterior column support versus posterior release and pedicle screw instrumentation. SUMMARY OF BACKGROUND DATA: Treatment of single, structural, lumbar and thoracolumbar curves in patients with adolescent idiopathic scoliosis (AIS) has been the subject of some debate. Previous papers directly comparing these approaches are problematic because of heterogeneity of the groups, nonrandomized protocols, and surgeon bias and variation of instrumentation (upper instrumented vertebrae and lower instrumented vertebrae) in relation to the defined Cobb angle (upper end vertebra and lower end vertebrae). This report sought to remedy these flaws by analyzing a database of Lenke 5C AIS and performing matched cases. METHODS: We analyzed 96 patients with Lenke 5C AIS curves based on radiographic and clinical data at 3 institutions, surgically treated between 2001 and 2005 with minimum 2-year follow-up. Case matched criteria (age within 1 year, sex, curve within 5°, lower end vertebrae, and lower instrumented vertebrae) yielded 21 matched patient pairs. We evaluated and compared multiple clinical and radiographic parameters. RESULTS: We observed no significant statistical differences between groups in any preoperative clinical or radiographic parameters. At final follow-up, the major curve measured 8° (83%) in the posterior spinal fusion group, compared with 13° (72%) in the anterior spinal fusion group (p = .002). Estimated blood loss was similar in both groups. Hospital stay was significantly shorter in the posterior spinal fusion group. There were no differences in radiographic complications, such as proximal junctional kyphosis. CONCLUSIONS: At a minimum of 2 years' follow-up in a multicenter, matched case analysis, adolescents with Lenke 5C curves demonstrated statistically significantly better curve correction and shorter hospital stays when treated with a posterior release with pedicle screw instrumented fusion compared with an anterior instrumented fusion with dual rods for similar patient populations.

Biomechanical evaluation of segmental occipitoatlantoaxial stabilization techniques.

STUDY DESIGN: Biomechanical study using human cadaveric cervical spines. OBJECTIVE: To evaluate the construct stability of 3 different segmental occipitoatlantoaxial (C0-C1-C2) stabilization techniques. SUMMARY OF BACKGROUND DATA: Different C0-C1-C2 stabilization techniques are used for unstable conditions in the upper cervical spine, all with different degrees of risk to the vertebral artery. Techniques with similar stability but less risk to the vertebral artery may be advantageous. METHODS: Six human cadaveric cervical spines (C0-C5) (age: 74 +/- 5.0 years) were used. After testing the intact spines, instability was created by transecting the transverse and alar ligaments. The spines were instrumented from the occiput to C2 using 3 different techniques which varied in their attachment to C2. All spines had 6 screws placed into the occiput along with lateral mass screws at C1. The 3 variations used in attachment to C2 were (1) C2 crossing laminar screws, (2) C2 pedicle screws, and (3) C1-C2 transarticular screws. The C1 lateral mass screws were removed before placement of the C1-C2 transarticular screws. Range of motion across C0-C2 was measured for each construct. The data were analyzed using repeated measures ANOVA. The following post hoc comparisons were made: (1) intact spine versus each of the 3 techniques, (2) laminar screw technique versus the pedicle screw technique, and (3) laminar screw technique versus the transarticular screw technique. The level of significance was alpha = 0.01 (after Bonferroni correction for 5 comparisons). RESULTS: All 3 stabilization techniques significantly decreased range of motion across C0-C2 compared to the intact spine (P < 0.01). There was no statistical difference among the 3 stabilization methods in flexion/extension and axial rotation. In lateral bending, the technique using C2 crossing laminar screws demonstrated a trend toward increased range of motion compared to the other 2 techniques. CT scans in both axial and sagittal views demonstrated greater proximity to the vertebral artery in the pedicle and transarticular screw techniques compared to the crossing laminar screw technique. CONCLUSION: Occipitoatlantoaxial stabilization techniques using C2 crossing laminar screws, C2 pedicles screws, and C1-C2 transarticular screws offer similar biomechanical stability. Using the C2 crossing laminar screw technique may offer an advantage over the other techniques due to the reduction of the risk to the vertebral artery during C2 screw placement.

Comparison of surgical treatment in Lenke 5C adolescent idiopathic scoliosis: anterior dual rod versus posterior pedicle fixation surgery: a comparison of two practices.

STUDY DESIGN: Multicenter analysis of 2 groups of patients surgically treated for Lenke 5C adolescent idiopathic scoliosis (AIS). OBJECTIVE: Compare patients with Lenke 5C scoliosis surgically treated with anterior spinal fusion with dual rod instrumentation and anterior column support with patients surgically treated with posterior release and pedicle screw instrumentation. SUMMARY OF BACKGROUND DATA: Treatment of single, structural, lumbar, and thoracolumbar curves in patients with AIS has been the subject of some debate. Advocates of the anterior approach assert that their technique spares posterior musculature and may save distal fusion levels, and that with dual rods and anterior column support the issues with nonunion and kyphosis have been obviated. Advocates of the posterior approach assert that with the change to posterior pedicle screw based instrumentation that correction and levels are equivalent, and the posterior approach avoids the issues with nonunion and kyphosis. This report directly compares the results of posterior versus anterior instrumented fusions in the operative treatment of adolescent idiopathic Lenke 5C curves. METHODS: We analyzed 62 patients with Lenke 5C based on radiographic and clinical data at 2 institutions: 31 patients treated with posterior, pedicle-screw instrumented fusions at 1 institution (group PSF); and 31 patients with anterior, dual-rod instrumented fusions at another institution (group ASF). Multiple clinical and radiographic parameters were evaluated and compared. RESULTS: The mean age, preoperative major curve magnitude, and preoperative lowest instrumented vertebral (LIV) tilt were similar in both groups (age: PSF = 15.5 years, ASF = 15.6 years; curve size: PSF = 50.3 degrees +/- 7.0 degrees , ASF = 49.0 degrees +/- 6.6 degrees ; LIV tilt: PSF = 27.5 degrees +/- 6.5 degrees , ASF = 27.8 degrees +/- 6.2 degrees ). After surgery, the major curve corrected to an average of 6.3 degrees +/- 3.2 degrees (87.6% +/- 5.8%) in the PSF group, compared with 12.1 degrees +/- 7.4 degrees (75.7% +/- 14.8%) in the ASF group (P < 0.01). At final follow-up, the major curve measured 8.0 degrees +/- 3.0 degrees (84.2% +/- 5.8% correction) in the PSF group, compared with 15.9 degrees +/- 9.0 degrees (66.6% +/- 17.9%) in the ASF group (P = 0.01). This represented a loss of correction of 1.7 degrees +/- 1.9 degrees (3.4% +/- 3.7%) in the PSF group, and 3.8 degrees +/- 4.2 degrees (9.4% +/- 10.7%) in the ASF group (P = 0.028). The LIV tilt decreased to 4.1 degrees +/- 3.4 degrees after surgery in the PSF group, and 4.5 degrees +/- 3.7 degrees in the ASF group. At final follow-up, the LIV tilt was 5.1 degrees +/- 3.5 degrees in the PSF group, and 4.5 degrees +/- 3.7 degrees in the ASF group. EBL was identical in both groups, and length of hospital stay was significantly (P < 0.01) shorter in the PSF group (4.8 vs. 6.1 days). There were no complications in either group which extended hospital stay or required an unplanned second surgery. CONCLUSION: At a minimum of 2-year follow-up, adolescents with Lenke 5C curves demonstrated statistically significantly better curve correction, less loss of correction over time, and shorter hospital stays when treated with a posterior release with pedicle screw instrumented fusion compared with an anterior instrumented fusion with dual rods for similar patient populations.

Effect of uncovertebral joint excision on the motion response of the cervical spine after total disc replacement.

STUDY DESIGN: In vitro biomechanical study. OBJECTIVE: To quantify the effects of uncinatectomy on cervical motion after total disc replacement (TDR). SUMMARY OF BACKGROUND DATA: The effect of uncinatectomy on TDR motion is unknown. Partial uncinatectomy may be required to decompress the foramen; however, the residual uncinates can potentially limit TDR motion and serve as a source of progressive spondylosis. Complete resection of the uncinates may decrease this risk yet endanger destabilizing the segment. METHODS: Seven human cervical spines (C3-C7) (age, 63.4 +/- 6.9 years) were tested first intact and then after implantation of a metal-on-polyethylene ball-and-socket semiconstrained prosthesis at C5-C6. Following this, gradually increased uncinatectomy was performed in the following order: 1) right partial-posteromedial (two thirds), 2) right complete, and 3) bilateral complete resection. Specimens were tested in flexion-extension, lateral bending, and axial rotation (+/-1.5 Nm). Flexion-extension was tested under 150 N follower preload. RESULTS: TDR without uncinatectomy increased C5-C6 flexion-extension range of motion from 8.4 degrees +/- 3.5 degrees to 11.6 degrees +/- 3.4 degrees, but statistical significance was not reached (P > 0.05). Lateral bending decreased from 6.2 degrees +/- 2.2 degrees to 3.1 degrees +/- 1.4 degrees, with a trend for statistical significance (P = 0.07). Axial rotation decreased from 5.5 degrees +/- 2.4 degrees to 4.3 degrees +/- 1.4 degrees after the implantation (P > 0.05). Both right partial and right complete uncinatectomy resulted in nearly symmetrical restoration of lateral bending to intact values and significantly increased flexion-extension compared with intact (P < or = 0.05); however, axial rotation still did not differ from intact (P > 0.05). Complete bilateral resection also restored lateral bending to intact values (7.3 degrees +/- 2.7 degrees, P > 0.05); however, it resulted in significant increase in range of motion in flexion-extension (14.1 degrees +/- 3.0 degrees, P < or = 0.05) and axial rotation (8.7 degrees +/- 2.4 degrees, P < or = 0.05). CONCLUSION: Unilateral complete or even partial uncinatectomy can normalize lateral bending after TDR. Bilateral complete uncinatectomy is not necessary to restore lateral bending and may result in significantly increased range of motion in flexion-extension and axial rotation compared with intact values.

Orthopaedic complications of myotubular myopathy.

Myotubular myopathy is a rare genetic disease that was uniformly fatal until recent developments in long-term ventilation. Today, however, it is not unusual for a patient to live into the second decade. The orthopaedic manifestations of the disease have not been reported in the literature. We present our experience with complications related to the spine and extremities in a series of 4 patients with this disease who have survived beyond early childhood.

Atlantoaxial instability secondary to rheumatoid arthritis.

Multiple elements contribute to the stability of the anterior C1-C2 articulation, making this region subject to pathologies including trauma, inflammation, infection, and congenital deformities. C1-C2 instability places a patient at risk for significant neurologic compromise. Radiologic imaging plays a fundamental role in diagnosing atlantoaxial instability, indicating etiology, showing details of associated abnormalities, and providing information for planning treatment.

Pseudarthrosis in adult spinal deformity following multisegmental instrumentation and arthrodesis.

BACKGROUND: There have been few detailed reports concerning pseudarthrosis following spinal instrumentation and arthrodesis in adults with spinal deformity since the introduction of modern segmental fixation techniques. The purposes of this study were to analyze the prevalence, risk factors, and outcome scores on the Scoliosis Research Society Instrument-24 associated with pseudarthrosis following instrumentation and arthrodesis for the treatment of spinal deformity in adults. METHODS: A clinical and radiographic assessment of 232 adults with spinal deformity who were treated surgically at a single institution was conducted. The average age of the patients was 40.8 years, and the operation was a primary procedure in 150 patients and a revision procedure in eighty-two patients. All patients who underwent a long (four vertebrae or more) spinal instrumentation and arthrodesis with a minimum follow-up of two years were included in the analysis. Clinical outcomes were assessed with the Scoliosis Research Society questionnaire. RESULTS: Forty patients had a pseudarthrosis. Factors that were found to be significantly associated with pseudarthrosis were preoperative thoracolumbar kyphosis of >20 degrees (p < 0.0001), an age of more than fifty-five years (p = 0.001), arthrodesis to S1 compared with arthrodesis to L5 or a cephalad level (p = 0.002), and arthrodesis of more than twelve vertebrae (p = 0.037). Patients with a pseudarthrosis had lower total outcome scores on the Scoliosis Research Society questionnaire, on the average, than those without a pseudarthrosis (p = 0.001). CONCLUSIONS: The prevalence of pseudarthrosis following long arthrodesis with use of modern segmental spinal instrumentation for the treatment of spinal deformity in adults was 17%, and the clinical outcome in these patients can be negatively affected by the pseudarthrosis.

Proximal junctional kyphosis in adult spinal deformity following long instrumented posterior spinal fusion: incidence, outcomes, and risk factor analysis.

STUDY DESIGN: To analyze patient outcomes and risk factors associated with proximal junctional kyphosis (PJK) in adults undergoing long posterior spinal fusion. OBJECTIVES: To determine the incidence of PJK and its effect on patient outcomes and to identify any risk factors associated with developing PJK. SUMMARY OF BACKGROUND DATA: The incidence of PJK and its affect on outcomes in adult deformity patients is unknown. No study has concentrated on outcomes of patients with PJK. Risk factors for developing PJK are unknown. METHODS: Radiographic data on 81 consecutive adult deformity patients with minimum 2-year follow-up (average 5.3 years, range 2-16 years) treated with long instrumented segmental posterior spinal fusion was collected. Preoperative diagnosis was adult scoliosis, sagittal imbalance or both. Radiographic measurements analyzed included the sagittal Cobb angle at the proximal junction on preoperative, early postoperative, and final follow-up standing long cassette radiographs. Additional measurements used for analysis included the C7-Sacrum sagittal plumb and the T5-T12 sagittal Cobb. Postoperative SRS-24 scores were available on 73 patients. RESULTS: Incidence of PJK as defined was 26%. Patients with PJK did not have lower outcomes scores. PJK did not produce a more positive sagittal C7 plumb. PJK was more common at T3 in the upper thoracic spine. CONCLUSIONS: Incidence of proximal junctional kyphosis was high, but SRS-24 scores were not significantly affected in patients with PJK. The sagittal C7 plumb was not significantly more positive in PJK patients. No patient, radiographic, or instrumentation variables were identified as risk factors for developing PJK.

Pseudarthrosis in primary fusions for adult idiopathic scoliosis: incidence, risk factors, and outcome analysis.

STUDY DESIGN: A retrospective study. OBJECTIVE: To analyze the incidence, characteristics, risk factors, and Scoliosis Research Society Instrument-24 (SRS-24) outcome scores of pseudarthrosis in adult idiopathic scoliosis primary fusions. SUMMARY OF BACKGROUND DATA: The healing of spinal fusion is complex and difficult to study in a clinical setting. There are no detailed reports on pseudarthrosis in primary fusion for adult idiopathic scoliosis since the introduction of "modern" segmental fixation techniques. METHODS: A retrospective chart and radiographic review of 96 patients (average age 42.2 years; range 18.2-62.9 years) with adult idiopathic scoliosis undergoing first time (primary) spinal instrumentation and fusion with a minimum 2-year follow-up (average 5.9 years; range 2-16.8 years) treated at a single institution between 1985 and 2001 were analyzed. RESULTS: Sixteen patients had pseudarthroses (17%). Fifty-nine percent of the pseudarthroses occurred between T9 and L1, and 81% presented with multiple levels involved (2-6 levels). The site of crosslinks or dominoes correlated with pseudarthrosis site in 69%. Pseudarthroses were detected radiologically at 32.4 months (range 12-67 months) postoperatively. Patient age at surgery more than 55 years significantly correlated with pseudarthrosis (P = 0.007). The number of fused levels more than 12 vertebrae is also significantly correlated with pseudarthrosis (P = 0.03). Smoking history and comorbidity did not increase the pseudarthrosis rate (P = 0.71 and 0.19, respectively). A larger preoperative Cobb angle (> or =70 degrees) and a greater thoracic kyphosis (T5-T12 >40 degrees) did not correlate with a higher pseudarthrosis rate (P = 0.76 and 0.73, respectively). Thoracolumbar kyphosis (T10-L2 > or =20 degrees) correlated with a significantly higher pseudarthrosis rate (P < 0.0001). Preoperative global sagittal and coronal imbalance did not increase the pseudarthrosis rate (P = 0.45 and 0.62, respectively). Patients with pseudarthrosis had lower SRS-24 scores than those without (P = 0.01). CONCLUSION.: The incidence of pseudarthrosis following adult idiopathic scoliosis primary fusion was 17%. The pseudarthrosis was most likely to occur at the thoracolumbar junction. Older patients (>55 years), longer fusion (>12 vertebrae), and those with thoracolumbar kyphosis (> or =20 degrees) demonstrated increased risk for pseudarthrosis. Patients' outcomes as measured by the SRS-24 were "negatively" affected by the pseudarthrosis.

Perioperative halo-gravity traction in the treatment of severe scoliosis and kyphosis.

STUDY DESIGN: A retrospective analysis of patients that underwent perioperative halo-gravity traction as an adjunct to modern instrumentation methods in the treatment of severe scoliosis and kyphosis. OBJECTIVE: To review the clinical and radiographic results of perioperative halo-gravity traction in several time periods. SUMMARY OF BACKGROUND DATA: Few reports to our knowledge review the use of perioperative and intraoperative halo-gravity traction in this patient population. METHODS: A total of 33 patients with severe operative scoliosis, kyphoscoliosis, or kyphosis were studied based on hospital records, standing pretreatment, traction (before anterior/posterior fusion), postoperative (each stage), and final radiographs. Patients were analyzed by age at date of examination (range, 2-20 years; mean, 13.8 years), gender (18 male, 15 female), major coronal curve magnitude (range, 22 degrees-158 degrees; average, 84 degrees), major compensatory coronal curve magnitude (range, 8 degrees-123 degrees; average, 51 degrees), major sagittal curve magnitude (range, 13 degrees-143 degrees; average, 78 degrees), traction protocol, and procedure type. Halo-traction-related, short- and long-term complications were noted in each case. RESULTS: The major coronal curve reduced 38 degrees or 46% after posterior spinal fusion compared to pretreatment radiographs. At an average of 44 months radiographic follow-up (range, 24-107 months), the loss of correction averaged 7 degrees for major coronal curves and 4 degrees of thoracic kyphosis. Clinical complications were noted in the perioperative and long-term time periods. CONCLUSIONS: The treatment of severe scoliosis can be very challenging despite the benefits of modern instrumentation methods, especially if there is a significant kyphosis or a history of intraspinal pathology. Halo-gravity traction is a safe, well-tolerated method of applying gradual, sustained traction to maximize postoperative correction in this difficult population. There were no permanent neurologic deficits in this series.

Long adult deformity fusions to L5 and the sacrum. A matched cohort analysis.

STUDY DESIGN: A matched cohort analysis of long adult deformity fusions according to distal fusion level (L5 vs. S1). OBJECTIVE.: To compare the results of long adult deformity fusions to either L5 or the sacrum in the presence of a "healthy" 5-1 disc using a matched cohort analysis. SUMMARY OF BACKGROUND DATA: For adult spinal deformity, the decision often arises whether to terminate a long fusion at L5 or the sacrum. The decision is especially challenging in the presence of a "healthy" (Grade 0 to 1 degeneration) 5-1 disc. MATERIALS AND METHODS: A total of 95 adult deformity patients that underwent fusion from the thoracic spine to either L5 or the sacrum were sorted according to five preoperative criteria: 5-1 disc status, patient age, smoking status, number of levels fused, and sagittal balance. Two cohorts (L5, 27 patients; sacrum, 12 patients) were precisely matched according to the five criteria. Patients were evaluated at 2-year minimum follow-up according to radiographic data, complications, and SRS-24 outcomes. RESULTS: Correction of sagittal imbalance was superior for sacrum patients (C7 plumb line: L5, 0.9 cm; sacrum, 3.2 cm; P = 0.03). At latest follow-up (L5, 5.2 years; sacrum, 3.7 years), 67% of L5 patients had radiographic evidence of advanced 5-1 disc degeneration and the L5 cohort tended to have inferior sagittal balance (C7 plumb line: L5, +4.0 cm; sacrum, +1.2 cm; P = 0.06). The sacrum cohort, however, required more surgical procedures (L5, 1.7; sacrum, 2.8; P = 0.03) and experienced a greater frequency of major complications (L5, 22%; sacrum, 75%; P = 0.02), including nonunion (L5, 4%; sacrum, 42%; P = 0.006) and medical morbidity (L5, 0%; sacrum, 33%; P = 0.001). SRS-24 scores reflected a similar patient assessment of outcome and function for the two cohorts (L5, 89; sacrum, 87). DISCUSSION AND CONCLUSION: At 3 to 5 years' mean follow-up, long adult fusions to the sacrum required more procedures and had a higher frequency of complications than similar fusions to L5. For fusions to L5, subsequent subjacent disc degeneration is common and may be associated with a forward shift in sagittal balance. The ultimate influence of these factors on long-term outcomes remains to be seen.

Selective thoracic fusion for adolescent idiopathic scoliosis with C modifier lumbar curves: 2- to 16-year radiographic and clinical results.

STUDY DESIGN: Retrospective clinical and radiographic review with functional outcome assessment. OBJECTIVES: To evaluate outcome of selective thoracic fusion for adolescent idiopathic scoliosis in the presence of widely deviated compensatory lumbar curves. SUMMARY OF BACKGROUND DATA: Previous reports on the results of selective thoracic scoliosis fusion have not specifically focused on deformities with widely deviated lumbar curves. Whether these challenging deformities are best treated with selective thoracic fusion or fusion of both curves remains unclear. METHODS: Forty-four consecutive patients with adolescent idiopathic scoliosis with main thoracic, compensatory minor lumbar "C" modifier curves underwent selective thoracic fusion at a single institution (1987-2000). Radiographs were analyzed before surgery, at 1 week, 2 years, and latest follow-up (2-16 years; mean 5.0 years). RESULTS: A mean 36% thoracic correction was closely matched by a 34% lumbar correction at latest follow-up. A majority of spontaneous lumbar correction occurred at its cephalad segments (P = 0.001). Spontaneous correction of lumbar apical translation occurred in a majority of patients (prognostic factors identified). Global coronal imbalance (2-5 cm) was common before surgery and was a significant risk factor (P = 0.04) for global imbalance at latest follow-up. Postoperative bracing was not utilized, and there were no reoperations. Patients with coronal imbalance (2-5 cm) at latest follow-up had slightly inferior SRS-24 results. CONCLUSIONS: Satisfactory results are achieved with selective thoracic fusion of properly selected C modifier lumbar curves. Correction of the lumbar curve results principally from a decrease in the tilt of its upper vertebrae, but not necessarily improved apical translation. Mild coronal imbalance was well tolerated and has not necessitated distal extension of the fusion.

Pedicle subtraction osteotomy for the treatment of fixed sagittal imbalance. Surgical technique.

BACKGROUND: Fixed sagittal imbalance (a syndrome in which the patient is only able to stand with the weight-bearing line in front of the sacrum) has many etiologies. The most commonly reported technique for correction is the Smith-Petersen osteotomy. Few reports on pedicle subtraction procedures (resection of the posterior elements, pedicles, and vertebral body through a posterior approach) are available in the peer-reviewed literature. We are aware of no report involving a substantial number of patients with coexistent scoliosis who underwent pedicle/vertebral body subtraction for the treatment of fixed sagittal imbalance. METHODS: Twenty-seven consecutive patients in whom sagittal imbalance was treated with lumbar pedicle subtraction osteotomy at one institution were analyzed. Radiographic analysis included assessment of thoracic kyphosis, lumbar lordosis, lordosis through the pedicle subtraction osteotomy site, and the C7 sagittal plumb line. Outcomes analysis was performed with use of a before-and-after pain scale, items from the Oswestry questionnaire, and the Scoliosis Research Society (SRS) questionnaire after a minimum duration of follow-up of two years. Complications and radiographic findings were also analyzed for the entire group. RESULTS: Overall, the average increase in lordosis was 34.1 degrees and the average improvement in the sagittal plumb line was 13.5 cm. One patient had development of a lumbar pseudarthrosis through the area of pedicle subtraction osteotomy, and six patients had development of a thoracic pseudarthrosis. Two patients had development of increased kyphosis at L5/S1, caudad to the fusion, resulting in some loss of sagittal correction. There were significant improvements in the overall Oswestry score (p < 0.0001) and the pain-scale score (p = 0.0002). Most patients reported improvement in terms of pain and self-image as well as overall satisfaction with the procedure. CONCLUSIONS: Pedicle subtraction osteotomy is a useful procedure for patients with fixed sagittal imbalance. A worse clinical result is associated with increasing patient comorbidities, pseudarthrosis in the thoracic spine, and subsequent breakdown caudad to the fusion.

Comparison of SRS questionnaire results submitted by both parents and patients in the operative treatment of idiopathic scoliosis.

STUDY DESIGN: A prospective, cross-sectional analysis of patients with operative idiopathic scoliosis comparing Scoliosis Research Society's Outcomes Instrument (SRS-24) scores from both parents and patients obtained separately on the same day along with pertinent radiographic data. OBJECTIVE: To determine the correlation of parents' and patients' perspectives of the patients' preoperative and postoperative experience using the SRS-24 questionnaire emphasizing parent-patient disparities. SUMMARY OF BACKGROUND DATA: No report to our knowledge has addressed the association between parent assessments of their child's presurgical and postsurgical outcome as verified by SRS-24 questionnaire data. MATERIALS AND METHODS: A total of 101 patients with operative idiopathic scoliosis were analyzed based on paired parent-patient SRS-24 data and radiographs performed on the same day. Patients were analyzed by age at date of examination (9-23 years, mean 17 +/- 5 years), gender (16 male, 85 female), major curve magnitude (41-126 degrees ), procedure type [preoperative (22 pairs), anterior spinal fusion (49 pairs), anterior spinal fusion/posterior spinal fusion (19 pairs), posterior spinal fusion (46 pairs)], and time from surgery (preoperative, postoperative 1-93 months, mean 24 months). All questionnaire scores were classified based on domains of pain, self-image, function, overall satisfaction, and total score. RESULTS: In overall time periods, parents consistently scored higher than their children in the self-image (P = 0.0001), satisfaction (P = 0.0001), and total score (P = 0.04), but not pain or function. Before surgery, parents overestimated patients' scores in self-image (P = 0.002) by 7.5% but not other domains. Satisfaction differences (P = 0.04) improved with increasing age of the patient, but not other domains. There were no significant differences with gender or preoperative/postoperative major curve magnitudes. CONCLUSION: Based on SRS-24 data, parents typically scored higher than their children in the operative treatment of idiopathic scoliosis in total score, self-image, and overall satisfaction. Some parent-patient scores correlated better with increasing age of the patient, and later in the postoperative period.

Late complications of adult idiopathic scoliosis primary fusions to L4 and above: the effect of age and distal fusion level.

UNLABELLED: STUDY DESIGN A retrospective analysis of primary cases of adult idiopathic scoliosis treated with long instrumented fusions from the thoracic spine proximally to segments that range from T11 to L4 distally. OBJECTIVE: To analyze whether patients requiring revision surgery had lower postoperative SRS-24 scores; age >or=40 years correlated with higher rates of revision surgery; disc degeneration below the fusion occurred more commonly with a more distal lowest instrumented vertebra or older patient age (>or=40 years); and whether smokers had higher rates of major complications or revision surgery. SUMMARY OF BACKGROUND DATA: Few reports describe complications related to primary long fusions using modern 2+ rods, hook/pedicle screw instrumentation methods in the treatment of adult idiopathic scoliosis. METHODS: Sixty-seven patients were analyzed with an average age of 38.8 years (range 21-61 years). The average clinical follow-up was 7.8 years (range 2-16 years): 42 patients had >5 years follow-up, including 23 patients with >10 years follow-up. Patients were categorized by age (< or >or=40 years) and level of the lowest instrumented vertebra (T11-L2 vs. L3-L4). Upright radiographs and postoperative SRS-24 questionnaires from the latest follow-up date were analyzed. RESULTS: Patients requiring revision surgery had lower total score (average 72.0) than those that did not (total score = 94.2; P = 0.01). More specifically, patients with pseudarthrosis had lower total scores (average 74.7) than those without (average total score = 93.5; P = 0.02). When analyzing age, there were similar rates of pseudarthrosis, but higher rates of transition syndrome (2) and sagittal/coronal imbalance (1 each) in patients >or=40 years. Subsequent distal disc degeneration did not correlate significantly with more distal lowest instrumented vertebra or older patient age. Smokers did not have higher rates of major complications or revision surgery than nonsmokers. CONCLUSIONS: Patients with adult idiopathic scoliosis and long fusions had similar pseudarthrosis rates, but higher rates of transition syndrome when lowest instrumented vertebra was L3-L4 relative to levels T11-L2. When categorized by age, complication rates were similar in each group. Patients with pseudarthroses or other diagnoses requiring revision surgery had lower SRS-24 total scores than those without (P = 0.02 and P = 0.01, respectively).

Thoracolumbar deformity arthrodesis to L5 in adults: the fate of the L5-S1 disc.

STUDY DESIGN: A retrospective clinical and radiographic analysis of long adult deformity fusions terminating at L5. OBJECTIVES: To define the results of thoracolumbar fusions to L5 in adult deformity patients with critical evaluation for potential subsequent L5-S1 disc degeneration and L5 implant loosening. SUMMARY OF BACKGROUND DATA: Few studies have reported the results of long adult fusions to L5 and the potential for subsequent advanced L5-S1 disc degeneration is unknown. MATERIALS AND METHODS: Thirty-four consecutive patients fused from the thoracic spine to L5 at a single institution were evaluated at a mean follow-up of 5.6 years (2.1-14.3 years). SRS-24 functional outcome questionnaire results were obtained for all patients at most recent follow-up. RESULTS: By latest follow-up, subsequent advanced L5-S1 disc degeneration (SAD) developed in 19 of 31 patients (61%) assessed as having "healthy" discs before surgery. SAD was associated with a forward shift in sagittal balance (P = 0.02) and need for revision surgery (P = 0.02). Risk factors for the development of SAD were preoperative positive sagittal balance (P = 0.01), younger age (P = 0.03), and the presence of even mild radiographic degeneration before surgery (P = 0.004). Loss of L5 implant fixation occurred in six patients (18%) and was associated with deep seating of L5 within the pelvis (P = 0.0001). Inferior SRS-24 outcome measures were associated with preoperative advanced L5-S1 disc degeneration and the development of postoperative sagittal imbalance. CONCLUSIONS: Subsequent L5-S1 DDD developed in 61% of patients after long adult fusions to L5 and was associated with a significant loss of sagittal alignment and an increased likelihood for or definite need for another operation. Loss of L5 implant fixation is not uncommon, especially in patients with a deep-seated L5 vertebra.