Instrumented fusion in a 12-month-old with atlanto-occipital dislocation: case report and literature review of infant occipitocervical fusion.

BACKGROUND: The treatment of atlantoaxial dislocation in very young children is challenging and lacks a consensus management strategy. DISCUSSION: We review the literature on infantile occipitocervical (OC) fusion is appraised and technical considerations are organized for ease of reference. Surgical decisions such as graft type and instrumentation details are summarized, along with the use of bone morphogenic protein and post-operative orthoses. ILLUSTRATIVE CASE: We present the case of a 12-month-old who underwent instrumented occipitocervical (OC) fusion in the setting of traumatic atlanto-occipital dislocation (AOD). CONCLUSION: Occipitocervical (OC) arthrodesis is obtainable in very young infants and children. Surgical approaches are variable and use a combination of autologous grafting and creative screw and/or wire constructs. The heterogeneity of pathologic etiology leading to OC fusion makes it difficult to make definitive recommendations for surgical management.

Feasibility of rigid upper cervical instrumentation in children: tomographic analysis of children aged 2-6.

STUDY DESIGN: Tomographic analysis of occipitocervical (OC) instability in children aged between 2 and 6 years. OBJECTIVE: To assess the feasibility of screw placement in various bone anchors in the OC region in young children. SUMMARY OF BACKGROUND DATA: The use of rigid stabilization in the pediatric patients is gradually increasing. No study has comprehensively assessed the suitability of bony anatomy of the OC region for screw placement, especially in younger children. METHODS: A total of 50 patients (2-6 y, 10 each) who underwent skull and cervical CT scanning were randomly queried using an x-ray database. Screw placement was considered feasible if there was at least 0.5 mm of bone around a 3.5 mm screw through its trajectory. When the bony channel measured 3.5-4.0 mm, placement was considered possible, but difficult. RESULTS: Statistically, most measures were similar from the right to left sides. External occipital protuberance thickness increased from a mean value of 8.60 mm to a mean value of 10.73 mm. The mean C1 lateral mass length and width varied from 15.26 to 16.67 mm (P=0.056) and 7.34 to 8.58 mm (P=0.0005), respectively, with age. The mean C2 pedicle width and length varied from 3.85 to 4.18 and 17.11 to 19.8 mm, respectively, with age. The mean C2 laminar screw length increased from 20.4 to 22.66 mm with age (P<0.001). C2 lamina widths did not vary much by age. The mean C1-C2 transarticular path length and height increased from 26.7 to 33.6 mm and 2.58 to 3.09 mm, respectively, with age. The width was less directly variable by age (2.68-3.09 mm). CONCLUSIONS: Standard 3.5 mm screws can be used for OC and upper cervical instabilities in children aged between 2 and 6 years. Some anchor points appeared safer compared with others. The occipital keel, C1 lateral mass, and C2 laminae offered adequate space for screw placement in almost all cases. C2 pedicles offered adequate space in 49 sides and barely adequate space in 25 pedicles. Transarticular screws could be safely placed in only 4 of 100 sides. Close radiographic assessment of the vertebral artery course and bony architecture are recommended before surgery in pediatric patients with OC and upper cervical instability.

Preoperative patient-reported outcome score thresholds predict the likelihood of reaching MCID with surgical correction of adult spinal deformity.

BACKGROUND CONTEXT: Preoperative (pre-op) identification of patients likely to achieve a clinically meaningful improvement following surgery for adult spinal deformity (ASD) is critical, especially given the substantial cost and comorbidity associated with surgery. Even though pain is a known indication for surgical ASD correction, we are not aware of established thresholds for baseline pain and function to guide which patients have a higher likelihood of improvement with corrective surgery. PURPOSE: We aimed to establish pre-op patient-reported outcome measure (PROM) thresholds to identify patients likely to improve by at least one minimum clinically important difference (MCID) with surgery for ASD. STUDY DESIGN: This is a retrospective cohort study using prospectively collected data. PATIENT SAMPLE: We reviewed 172 adult patients' charts who underwent corrective surgery for spinal deformity. OUTCOME MEASURES: Included measures were the Visual Analog Scale for pain (VAS), Oswestry Disability Index (ODI), and Scoliosis Research Society-22 (SRS-22). Our primary outcome of interest was improvement by at least one MCID on the ODI and SRS-22 at 2 years after surgery. METHODS: As part of usual care, the VAS, ODI, and SRS-22 were collected pre-op and re-administered at 1, 2, and 5 years after surgery. MCIDs were calculated using a distribution-based method. Determining significant predictors of MCID at two years was accomplished by Firth bias corrected logistic regression models. Significance of predictors was determined by Profile Likelihood Chi-square. We performed a Youden analysis to determine thresholds for the strongest pre-op predictors. RESULTS: At year two, 118 patients (83%) reached MCID for the SRS and 127 (75%) for the ODI. Lower pre-op SRS overall, lower pre-op SRS pain, and higher pre-op SRS function predicted a higher likelihood of reaching MCID on the overall SRS (p < 0.05). Higher pre-op ODI, lower SRS pain and self-image, and higher SRS overall predicted a higher likelihood of reaching MCID on the ODI (p < 0.05). An ODI threshold of 29 predicted reaching MCID with a sensitivity of 0.89 and a specificity of 0.64 (AUC = 0.7813). An SRS threshold of 3.89 predicted reaching MCID with a sensitivity of 0.93 and specificity of 0.68 (AUC = 0.8024). CONCLUSIONS: We identified useful thresholds for ODI and SRS-22 with acceptable predictive ability for improvement with surgery for ASD. Pre-op ODI, SRS, and multiple SRS subscores are predictive of meaningful improvement on the ODI and/or SRS at 2 years following corrective surgery for spinal deformity. These results highlight the usefulness of PROMs in pre-op shared decision-making.

Relationship Between Preoperative Plasma Fibrinogen Concentration, Perioperative Bleeding, and Transfusions in Elective Adult Spinal Deformity Correction.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: This study sought to investigate the relationship between preoperative (preop) fibrinogen, bleeding, and transfusion requirements in adult spinal deformity corrections. SUMMARY OF BACKGROUND DATA: Blood loss after major spinal reconstruction increases the risks and costs of surgery. Preoperative fibrinogen levels may predict intra- and postoperative blood loss. METHODS: Data were collected from clinic charts and hospital medical records of all 142 of a single surgeon's consecutive adult spine patients undergoing 7 or more levels deformity correction surgeries from January 2011 to December 2014. t tests were used to compare perioperative variables between patients with total blood loss in the upper quartile (≥1,000 mL) and the remaining patients. Similarly, patients receiving >2 units of packed red cells (PRCs) were compared with others. Analysis of variance was used to compare the blood loss between the patients' groups (quartiles) based on their preoperative fibrinogen concentration. RESULTS: Mean total blood loss was 847.9 (±543.6) mL. Overall, mean preoperative fibrinogen concentration was 254.8 (±82.9) mg/dL. Patients with lower fibrinogen concentration (<193 mg/dL) experienced significantly higher blood loss than those with higher concentrations (p < .05). Patients with transfusion >2 units PRC had significantly greater number of spinal levels treated, higher mean operative time, total blood loss and lower mean preoperative fibrinogen than those transfused 2 or fewer units PRC (p < .05). Total blood loss correlated significantly with preoperative fibrinogen concentration (r = -0.51, p < .05). All the thromboelastography (TEG) variables (G, K, and Angle) correlated significantly with preoperative fibrinogen (p < .05). CONCLUSIONS: In our cohort undergoing correction of adult spinal deformity, patients with preoperative fibrinogen level lower than 193 mg/dL had significantly higher bleeding than their counterparts. Perioperative transfusion requirements correlated moderately both with the blood loss and preoperative fibrinogen concentration. Incorporation of preoperative fibrinogen allows better prediction of total perioperative blood loss and may therefore guide the treatment team in use of ameliorating therapies. LEVEL OF EVIDENCE: Level IV.

Should long-segment cervical fusions be routinely carried into the thoracic spine? A multicenter analysis.

BACKGROUND CONTEXT: Although recommendations for caudal "end level" in posterior cervical reconstruction remain highly variable, the benefits of routine extension of posterior cervical fusions into the thoracic spine remain unclear. PURPOSE: We compared clinical and radiographic outcomes in patients in whom posterior fusions ended in the cervical spine versus those in whom the fusion was extended into the thoracic spine. STUDY DESIGN/SETTING: A multicenter retrospective analysis of prospectively followed patients was carried out. PATIENT SAMPLE: A total of 177 adult spine patients undergoing three or more levels of posterior cervical fusions for degenerative disease from January 2008 to May 2013 comprised the patient sample. OUTCOME MEASURES: Cervical lordosis, C2-C7 sagittal plumbline, T1 slope, visual analog scale (VAS), Oswestry Disability Index (ODI), rate of pseudarthrosis, length of hospital stay (LOS), estimated blood loss (EBL), and operating room [OR] time were the outcome measures. METHODS: We assembled a multicenter (four sites) radiographic and clinical database of patients who had undergone three or more levels of posterior cervical fusions for degenerative disease from January 2008 to May 2013 with at least 2 years of postoperative (post-op) follow-ups. Patients were divided into two groups: Group 1 (fusion ending in the cervical spine) and group 2 (fusion extending into the thoracic spine). All radiographic measurements were performed by an independent experienced clinical researcher. RESULTS: Group 1 and Group 2 had 104 and 73 patients, respectively. Mean EBL for Group 2 was significantly higher than Group 1. Mean OR time and LOS were comparatively higher for Group 2 than Group 1 but were not statistically significant (p>.05). Mean cervical lordosis improved postoperatively in both groups. There were no statistically significant differences in change or maintenance of mean cervical lordosis (2 weeks vs. 2 years post-op) between the two groups (p>.05). Similarly, the change in mean C2-C7 sagittal plumbline and T1 slope was not statistically significantly different between the two groups or with follow-up(p>.05). Clinically, significant improvements in VAS and ODI were noted in both groups from preop to final follow-up, but the difference between groups was not statistically significant. Although the rate of pseudarthrosis was significantly higher in Group 1 (21.2%) than in Group 2 (10.96%), there were no statistically significant differences in adjacent segment degeneration or revision surgery rates between the groups. CONCLUSION: Both groups had similar clinical and radiographic outcomes. Extension of a posterior cervical fusion into the thoracic spine leads to lower pseudarthrosis rate, whereas stopping in the cervical spine yields lower EBL, OR time, and LOS, demonstrating that there are different benefits for each approach. However, although the optimal end-level remains debatable, there are scenarios in which upper thoracic extension should be considered. At this point, we recommend extension of surgery in smokers and other patients at increased risk for pseudarthrosis as well as in patients with anatomical limitations to strong C7 bone anchorage.

Is Preoperative Fibrinogen Testing Associated With Total Blood Loss in Adolescent Idiopathic Scoliosis Correction?

STUDY DESIGN: Retrospective analysis. OBJECTIVE: This study sought to investigate the potential association between preoperative fibrinogen, bleeding, and transfusion requirements in adolescent idiopathic scoliosis (AIS) corrections. SUMMARY OF BACKGROUND DATA: Blood loss after major spinal reconstruction increases the risks and costs of surgery. Preoperative fibrinogen levels may predict intra- and postoperative blood loss. METHODS: Data were collected from clinic charts and hospital medical records of all 110 of a single surgeon's consecutive AIS patients undergoing greater than three-level deformity correction surgeries from January 2011 to December 2013. Pearson test was used to investigate the correlation between bleeding and clinical variables, with level of significance set at α = 0.05. RESULTS: Mean total bleeding volume was 488 (±356) mL. Overall, mean preoperative fibrinogen concentration was 188.6 ± 32.8 mg/dL. Preoperative platelet counts, prothrombin time (PT), and activated partial thromboplastin time (aPTT) did not correlate significantly with preoperative fibrinogen concentration (p > .05). Both packed red cells (PRC) and packed red blood cells (PRBC) correlated significantly with preoperative fibrinogen (p < .05). The correlation between PRC and preoperative fibrinogen was -0.042. There was a negative correlation between PRBC and preoperative fibrinogen (r = -0.46). Overall mean thromboelastography (TEG) values were within normal range in both males and females and both had comparable TEG parameter values. All the TEG variables (G, K, and Angle) correlated significantly with preoperative fibrinogen (p < .05) but not with total blood volume (p > .05). The correlation coefficient between these TEG variables and preoperative fibrinogen were 0.51, 0.59, and 0.54, respectively. The total bleeding volume and % estimated blood volume correlated significantly with both PRC (r = 0.352, r = 0.376; p < .05) and PRBC (r = 0.621, r = 0.614; p < .05). CONCLUSIONS: In our cohort undergoing correction of AIS, preoperative fibrinogen levels exhibited a significant negative logarithmic correlation with total blood loss. TEG variables also correlated significantly with preoperative fibrinogen levels. Efforts should be made to incorporate this measure in perioperative blood management program for AIS corrections. LEVEL OF EVIDENCE: Level IV.

Surgical options for the treatment of cervical spondylotic myelopathy.

Cervical spondylotic myelopathy is a disease of the cervical spinal cord that results from circumferential compression of the degenerative cervical spine, often in a congenitally narrow spinal canal. Surgical recommendations must be based on patient characteristics, symptoms, function, and neuroradiologic findings. ACDF is an excellent option for one- or two-level spondylosis without retrovertebral disease. Anterior corpectomy and strut grafting may provide an improved decompression and is ideal for patients with kyphosis or neck pain. Laminectomy historically yields poor results from late deformity and late neurologic deterioration but yields improved results with good surgical technique. Laminoplasty was developed to address cervical stenosis of three or more segments and compares favorable with anterior corpectomy and fusion for neurologic recovery. Laminoplasty has a lower complication rate than corpectomy and strut grafting but has a higher incidence of postoperative axial symptoms.

Cervical stenosis in adults undergoing thoracolumbar deformity surgery: incidence, treatment, and complications: clinical article.

OBJECT: The goals of this study were to determine the incidence of occult cervical stenosis in patients over 50 years old with thoracolumbar deformity and to assess the risk of progressive cervical myelopathy after complex thoracolumbar reconstruction in asymptomatic or mildly symptomatic patients with cervical stenosis. METHODS: Charts and cervical imaging for patients who were over 50 years old when they had undergone thoracolumbar deformity surgery between 2005 and 2008 were reviewed. Patients with primary neurological disorders were excluded from the study. RESULTS: Seventy-three patients (56 women and 17 men) met the study inclusion criteria. The minimum follow-up time was 2 years. Fifty-eight percent of patients (42 of 73) had cervical stenosis on advanced imaging. Thirty-three patients had mild or moderate stenosis; only 3 of these patients had clinical myelopathy. Nine patients (12%) had critical cervical stenosis, as determined from imaging; among these patients, 3 had moderate or severe myelopathy. Patients with noncritical stenosis and no or mild myelopathy underwent thoracolumbar reconstruction without any postoperative progression of myelopathy. Patients with critical stenosis and/or moderate or severe myelopathy were offered cervical decompression prior to thoracolumbar reconstruction; those who accepted this offer did not have progression of myelopathy. One patient underwent thoracolumbar reconstruction first despite critical cervical stenosis. At 20 months, her cervical myelopathy had progressed, and she ultimately required cervical decompression. CONCLUSIONS: Cervical stenosis, even critical stenosis in some cases, was seen in more than one-half of the patients. Most presented without obvious cervical complaints. In those with mild to moderate stenosis and no or mild myelopathy, lengthy thoracolumbar reconstruction procedures were not associated with progression of the myelopathy. The authors recommend that all adults with thoracolumbar deformity undergo a detailed upper- and lower-extremity neurological examination prior to major thoracolumbar reconstruction.

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.

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.

The Ponte procedure: posterior only treatment of Scheuermann's kyphosis using segmental posterior shortening and pedicle screw instrumentation.

STUDY DESIGN: Case series. OBJECTIVE: To examine a consecutive series of surgically treated Scheuermann kyphosis that had a posterior only procedure with segmental pedicle screw fixation and segmental Ponte osteotomies. SUMMARY OF BACKGROUND DATA: The gold standard for surgical treatment of Scheuermann kyphosis (a rigid kyphosis associated with wedged vertebral bodies occurring in late childhood or adolescence) has been combined anterior and posterior approach surgery. Alberto Ponte has advocated a posterior-only procedure with posterior column shortening via segmental osteotomies, but his procedure has not been widely accepted owing to concerns that without anterior column support there would be a risk of correction loss and/or instrumentation failure. With the advent of improved spinal instrumentation and fixation with thoracic pedicle screws, the Ponte procedure may offer an advantage over anterior/posterior reconstruction. METHODS: The study prospectively enrolled 17 consecutive patients with Scheuermann kyphosis who were treated with the Ponte procedure by the senior surgeon at one institution. Standardized radiographic analysis was performed and included full-length coronal and sagittal radiographs preoperatively, postoperatively, and at final follow-up. Analysis also included the correction obtained through the most severe, wedged segments of the deformity by the osteotomies. RESULTS: Seventeen patients had the Ponte procedure satisfactorily performed. No patient needed an anterior approach to achieve sufficient correction or fusion. There were no reoperations for nonunion or instrumentation failure. Correction of the instrumented levels was 61% and of worst Cobb was mean 49%. The apex of the deformity was measured over the most deformed 3 to 7 wedged segments. The average correction across the apex was 9.3 degrees per osteotomy (range 5.9 to 15). No patient lost more than 4 degrees of correction through their instrumented and fused levels. There were no neurologic complications. There was one late infection with a solid fusion treated with instrumentation removal and intravenous antibiotics. CONCLUSIONS: Using thoracic pedicle screw instrumentation as the primary anchor, the Ponte procedure was successfully performed in 17 consecutive patients for Scheuermann kyphosis with no exclusions for the size or rigidity of the kyphosis. Results were as good as anterior/posterior historical controls with excellent correction and minimal loss of correction at final follow-up. This procedure avoids the morbidity and extended operative time attributed to the anterior approach. LEVEL OF EVIDENCE: Therapeutic study, level IV [case series (no, or historical, control group)].

High-grade isthmic dysplastic spondylolisthesis: monosegmental surgical treatment.

STUDY DESIGN: A prospective single arm cohort. OBJECTIVE.: To study the results of distraction reduction of high-grade isthmic dysplastic spondylolisthesis with posterior lumbar interbody fusion and posterior compression in a consecutive, prospectively collected series of adolescent patients. SUMMARY OF BACKGROUND DATA: High-grade isthmic dysplastic spondylolisthesis has been associated with a high complication and failure rate regardless of the method of surgical treatment, including in situ fusion, cast correction and fusion, anterior fusion, posterior instrumented fusion, and combination procedures. METHODS: A total of 18 adolescents with the diagnosis and a minimum 50% slip underwent the procedure of Gill decompression, temporary distraction with reduction of the deformity, complete lumbosacral discectomy, posterior lumbar interbody fusion with Harm's cage and autogenous iliac graft, and posterior monosegmental compression instrumentation with pedicular fixation. RESULTS: Follow-up ranged from 2.3 to 5 years. Slip improved from 77% to 13% and slip angle from 35 degrees to 3.8 degrees initially and 4.3 degrees at final follow-up. One patient had loss of 16 degrees of slip angle but achieved arthrodesis. Sacral inclination improved from 28 degrees to 39 degrees . There were no neurologic or infectious complications. There were no overt instrumentation failures. Arthrodesis was achieved in every instance. Two patients had structural complications, neither of which underwent reoperation. CONCLUSIONS: The index procedure provided near-anatomic correction of high-grade spondylolisthesis, which is maintained at a minimum 2-year follow-up without significant complications. There were two structural complications. Anterior column structural support and posterior compressive instrumentation help restore the necessary biomechanics to allow clinical fusion and success. This series has led the senior author to evolve his technique too ften include caudad fixation to the pelvis and/or cephalad fixation to L4.

An outcomes analysis of the treatment of cervical pseudarthrosis with posterior fusion.

STUDY DESIGN: A retrospective review of 33 consecutive patients treated with posterior fusion and selective nerve root decompression for the treatment of pseudarthrosis following anterior cervical discectomy and fusion. OBJECTIVES: Use standardized outcome measures to evaluate the results of posterior fusion with selective nerve root decompression as a treatment option for symptomatic pseudarthrosis of the cervical spine. SUMMARY OF BACKGROUND DATA: Pseudarthrosis after anterior cervical discectomy and fusion has been recognized as a cause of continued cervical pain and unsatisfactory outcomes. Debate continues as to whether a revision anterior approach or a posterior fusion procedure is the best treatment for symptomatic cervical pseudarthrosis. To our knowledge, standardized outcome measures have not been used to evaluate the results of either surgical treatment option; therefore, it is difficult to evaluate outcomes in these patients, let alone compare surgical treatment options. Data on fusion rates in these two surgical treatment groups suggest a trend of a higher fusion rate with utilization of a posterior revision procedure, but the largest study to date includes the study of only 19 patients treated with a posterior fusion. METHODS: Thirty-three consecutive patients with symptomatic pseudarthrosis following anterior cervical discectomy and fusion were treated with selective nerve root decompression and posterior fusion using iliac crest or local bone graft as well as posterior wiring and/or lateral mass plating. The average follow-up period was 46 months (range, 20-86 months). Patients were assessed using physical examination, flexion-extension lateral radiographs, and standardized outcome measures including the SF-36, Arthritis Impact Measurement Scales 2, and Cervical Spine Outcomes Questionnaire. RESULTS: All 33 patients (100%) demonstrated a solid fusion at their most recent follow-up, and all 33 patients noted significant improvement in their preoperative symptoms. No difference in fusion status was noted between those treated with iliac crest versus patients treated with local bone graft--all had a solid fusion; 72% of the patients were satisfied with the result of their surgery. Cervical Spine Outcomes Questionnaire pain scales demonstrated 52% of patients reported mild or nopain at follow-up, whereas 20% described their pain as "discomforting" and 28% of the patients continued to report moderate to severe pain. CONCLUSIONS: This is the first study to our knowledge to use standardized outcome measures to assess clinical outcome in patients treated with posterior fusion for pseudarthrosis after anterior cervical discectomy and fusion. Patients and surgeons need to understand the potential for success with this revision procedure but also be aware of the relatively high rate of continued moderate to severe pain observed in this patient population even after a solid fusion is achieved. All of the patients in this study fused with a single posterior fusion procedure, further supporting the relatively higher fusion rates observed in the literature using posterior fusion as a treatment for cervical pseudarthrosis. Our results also support the ability of surgeons to use local bone graft without iliac crest in a posterior fusion for cervical pseudarthrosis and therefore avoid the morbidity associated with iliac crest bone graft harvest.

The posterior approach for lumbar and thoracolumbar adolescent idiopathic scoliosis: posterior shortening and pedicle screws.

STUDY DESIGN: Prospective clinical case series. BACKGROUND DATA: Lumbar and thoracolumbar adolescent idiopathic scoliosis has traditionally been treated with an anterior approach and instrumentation. This anterior method often has had problems with kyphosis, pseudarthrosis, and loss of correction. The senior author has had good results treating these same lumbar and thoracolumbar curves posteriorly with wide posterior release and segmental instrumentation. In this series of his evolving technique, he adds pedicle screws as the sole anchor in the thoracolumbar/lumbar curves. OBJECTIVES: To prospectively evaluate outcomes, coronal and sagittal radiographic results, balance parameters, complications, and reoperations in a group of consecutive patients with lumbar and thoracolumbar adolescent idiopathic scoliosis. These patients were surgically treated with wide posterior release and segmental posterior screw instrumentation with 2-year minimum follow-up (range 26-47 months). METHODS: Sixty-two consecutive patients with thoracolumbar and lumbar adolescent idiopathic scoliosis were treated with a wide posterior release and segmental pedicle screw instrumentation limited to the curve defined by the Cobb measurement. The patients were evaluated clinically and radiographically at intervals up to 36 months. There was 2-year minimum follow-up. RESULTS: One patient was lost to follow-up. Of the remaining 61 patients, there were 51 Lenke 5 Type curves, 7 Lenke Type 3C curves, and 3 Lenke Type 6 curves. Only the curve defined by the Cobb measurement was fused. A total of 613 pedicle screws were placed safely. Average coronal correction of the thoracolumbar/lumbar curves was from 52 degrees to 10 degrees (80%). In the sagittal plane, lumbar lordosis was normalized from 41 degrees with a wide range (20 degrees -70 degrees ) to 42 degrees with a normal range (34 degrees -47 degrees ). There were no pseudoarthroses, no reoperations, no infections, no problems with screw placement, and excellent maintenance of correction at last follow-up. The lowest instrumented vertebrae had 81% correction of coronal angulation, center sacral line to lowest instrumented vertebrae was improved from 2.4 cm to 0.7 cm, and apex to center sacral line was improved from 5.2 cm to 1.5 cm. The C7 plumb line to center sacral line was also improved from 2.5 cm to 0.6 cm, illustrating the centering of the trunk. CONCLUSIONS: Wide posterior release and segmental pedicle screw instrumentation has excellent radiographic and clinical results with minimal complications. There were no pseudoarthroses and no reoperations.