Charles C. Edwards

Chronic donor site pain complicating bone graft harvesting from the posterior iliac crest for spinal fusion

To explore the relationship between surgical approach and chronic posterior iliac crest donor site pain, 151 bone graft harvests with follow-up periods longer than 1 year were evaluated using a detailed questionnaire and follow-up clinical visits. There was no difference in the incidence of chronic donor site pain between harvests performed through the primary midline incision versus a separate lateral oblique incision (28 vs 31%). Twice as many donor sites harvested for reconstructive spinal procedures were reported as having chronic pain as compared with those harvested for spinal trauma, regardless of approach used (39 vs 18%). The association of chronic donor site pain with residual back pain was also greater in the spinal reconstructive group. Thus, it appears that incidence of chronic donor site pain is more dependent on diagnosis than on surgical approach.

Complications and Outcomes of Pedicle Subtraction Osteotomies for Fixed Sagittal Imbalance

Study Design. Radiographic analysis, outcomes analysis (pain scale, Oswestry, SRS-24), and accumulation of complications. Outcomes and complications collected prospectively. Radiographic analysis performed retrospectively. Objectives. To assess the benefits and stress complications of pedicle subtractions osteotomies for patients with fixed sagittal imbalance. Summary of Background Data. Few reports on pedicle subtraction osteotomies exist in the peer-review literature for conditions other than trauma and ankylosing spondylitis. Materials and Methods. Thirty-three consecutive patients with sagittal imbalance treated with lumbar pedicle subtraction osteotomy at one institution (minimum 2-year follow-up) were analyzed. Complications were also analyzed for the entire group of consecutive pedicle subtraction osteotomies done at our institution to date (n = 66). Results. For the 33 patients with minimum 2-year follow-up, there were significant improvements in the overall Oswestry score (P 0.0001) and pain score (P = 0.0001). Most patients reported improvement in pain and self-image and reported overall satisfaction based on ultimate SRS-24 questionnaire. There was one pseudarthrosis in the lumbar spine through an area of pedicle subtraction osteotomy (area of previous laminectomy and nonunion), and six patients had thoracic pseudarthroses (levels other than the osteotomy level) and one patient had a pseudarthrosis at L5-S1. Two patients had acute angular kyphosis at the thoracolumbar junction at the proximal end of the construct. Five patients who experienced transient neurologic deficits resolved their deficits after central canal enlargement. Conclusions. The clinical result with pedicle subtraction osteotomy is reduced with pseudarthrosis in the thoracic or lumbar spine and subsequent breakdown adjacent to the fusion. For patients with a degenerative sagittal imbalance etiology the results were worse and the complications were higher. Central canal enlargement is critical.

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.

Corpectomy versus laminoplasty for multilevel cervical myelopathy: an independent matched-cohort analysis.

Study Design. Matched patient cohorts using retrospective chart and radiographic review with independent clinical and radiographic follow-up were reviewed. Objective. To compare the clinical and radiographic outcomes of multilevel corpectomy and laminoplasty using an independent matched-cohort analysis. Summary of Background Data. The treatment of choice for multilevel cervical myelopathy remains a matter of investigation. For the decompression of three or more motion segments, multilevel corpectomy and laminoplasty have proven effective while avoiding the pitfalls of laminectomy. Direct clinical comparisons of these two procedures are few in number and are limited by the heterogeneity in their patient groups. Methods. Medical records of all patients treated for multilevel cervical myelopathy with either multilevel corpectomy or laminoplasty between 1994 and 1999 at the Emory Spine Center were reviewed. From a pool of 38 patients meeting stringent inclusion and exclusion criteria, 13 patients who underwent multilevel corpectomy were blindly matched with 13 patients who underwent laminoplasty based on known prognostic criteria. A single physician independently evaluated each patient and their radiographs at their latest follow-up appointment. Results. The cohorts were well matched by age, duration of symptoms, severity of myelopathy (Nurick grade), and preoperative sagittal alignment (C2–C7). Mean operative time, blood loss, and hospital stay were nearly identical. The mean follow-up for multilevel corpectomy and laminoplasty were 49 and 40 months, respectively. Improvement in function averaged 1.6 Nurick grades after laminoplasty and 0.9 grades after multilevel corpectomy (P > 0.05). Subjective improvements in strength, dexterity, sensation, pain, and gait were similar for the two operations. The prevalence of axial discomfort at the latest follow-up was the same for each cohort, but the analgesic requirements tended to be greater for patients who underwent multilevel corpectomy. Sagittal motion from C2 to C7 decreased by 57% after multilevel corpectomy and by 38% after laminoplasty. One complication (C6–C7 herniated nucleus pulposus [HNP] requiring anterior discetomy with fusion) occurred in the laminoplasty group. Multilevel corpectomy complications included progression of myelopathy, nonunion, persistent dysphagia, persistent dysphonia, and subjacent motion segment ankylosis. Conclusions. Both multilevel corpectomy and laminoplasty reliably arrest myelopathic progression in multilevel cervical myelopathy and can lead to significant neurologic recovery and pain reduction in a majority of patients. Surprisingly, the laminoplasty cohort tended to require less pain medication at final follow-up than did the multilevel corpectomy cohort. Given this and the higher prevalence of complications among multilevel corpectomy patients, it is believed that laminoplasty may be the preferred method of treatment for multilevel cervical myelopathy in the absence of preoperative kyphosis.

Laminoplasty versus laminectomy and fusion for multilevel cervical myelopathy: an independent matched cohort analysis.

Study Design. A matched cohort clinical and radiographic retrospective analysis of laminoplasty and laminectomy with fusion for the treatment of multilevel cervical myelopathy. Objectives. To compare the clinical and radiographic outcomes of two procedures increasingly used to treat multilevel cervical myelopathy. Summary of Background Data. Traditional methods of treating multilevel cervical myelopathy (laminectomy and corpectomy) are reported to have a notable frequency of complications. Laminoplasty and laminectomy with fusion have been advocated as superior procedures. A comparative study of these two techniques has not been reported. Methods. Medical records of all patients treated for multilevel cervical myelopathy with either laminoplasty or laminectomy with fusion between 1994 and 1999 at our institution were reviewed. Thirteen patients that underwent laminectomy with fusion were matched with 13 patients that underwent laminoplasty. All patients and radiographs were independently evaluated at latest follow-up by a single physician. Results. Cohorts were well matched based on patient age, duration of symptoms, and severity of myelopathy (Nurick grade) before surgery. Mean independent follow-up was similar (25.5 and 26.2 months). Both objective improvement in patient function (Nurick score) and the number of patients reporting subjective improvement in strength, dexterity, sensation, pain, and gait tended to be greater in the laminoplasty cohort. Whereas no complications occurred in the laminoplasty cohort, there were 14 complications in 9 patients that underwent laminectomy with fusion patients. Complications included progression of myelopathy, nonunion, instrumentation failure, development of a significant kyphotic alignment, persistent bone graft harvest site pain, subjacent degeneration requiring reoperation, and deep infection. Conclusions. The marked difference in complications and functional improvement between these matched cohorts suggests that laminoplasty may be preferable to laminectomy with fusion as a posterior procedure for multilevel cervical myelopathy.

The Lenke Classification of Adolescent Idiopathic Scoliosis: How it Organizes Curve Patterns as a Template to Perform Selective Fusions of the Spine

Study Design. Retrospective radiographic review. Objectives. To analyze how the Lenke classification of adolescent idiopathic scoliosis provides a template of specific curve patterns that may be appropriate to perform selective fusion of the spine. Methods. A new triad classification system of adolescent idiopathic scoliosis has been developed. It consists of a curve type, a lumbar spine modifier (A, B, C), and a sagittal thoracic modifier (−, N, +). A selective fusion is termed when both the thoracic and thoracolumbar/lumbar curves deviate completely from the midline, but only the major curve (largest Cobb measurement) is fused, leaving the minor curve unfused and mobile. In this manner, selective thoracic fusions of the spine are potentially indicated for major main thoracic/minor lumbar curves (Types 1C and potentially 2C and 3C patterns) when the lumbar apex deviates off the center sacral vertical line. Conversely, selective thoracolumbar/lumbar fusions may be indicated for major thoracolumbar/lumbar–minor main thoracic curves, when the thoracic apex lies off the C7 plumbline (Type 5C and potentially 6C patterns). Importantly, additional analysis of ratios of structural characteristics between the main thoracic and thoracolumbar/lumbar curves are necessary to predict when a successful selective main thoracic or thoracolumbar/lumbar fusion will be feasible. Lastly, the clinical appearance of the patient’s truncal alignment is essential to confirm the aspirations of performing a selective spinal fusion. Results. Successful selective thoracic fusion of 1C (n = 36) and 2C (n = 8) curves have been performed in 44 consecutive patients with adolescent idiopathic scoliosis. The average thoracic curve was 61° before surgery and 39° at final follow-up. The average preoperative lumbar curve was 48°, decreasing to 32° postoperatively. A group of 21 consecutive patients with Type 5C or 6C major thoracolumbar/lumbar–minor main thoracic curves underwent a selective thoracolumbar/lumbar fusion. The average preoperative thoracolumbar/lumbar curve was 56° corrected to 22° at the 2-year follow-up. The average minor main thoracic curve preoperative was 38°, with spontaneous correction to 28° at 2 years postoperative. Discussion. Selective thoracic or thoracolumbar/lumbar fusion can be successfully performed in a variety of adolescent idiopathic scoliosis curve patterns. Careful attention to the preoperative Lenke curve classification, analysis of structural characteristics between the planned instrumented and noninstrumented regions of the spine, as well as a documented clinical examination that confirms the planned instrumented and fused regions of the spine to be the most clinically prominent are essential features to determine before surgery. No patients undergoing selective thoracic fusion have required extension of the fusion to the lumbar spine, whereas one patient with a selective thoracolumbar fusion required extension of the fusion up to include the thoracic spine due to continued thoracic progression with growth. Conclusions. Selective thoracic or thoracolumbar/lumbar fusions of the major curve can be successfully performed even when the minor curve completely deviates from the midline, based on the Lenke classification system, the analysis of structural criteria between the planned fused and unfused regions of the spine, and the clinical examination of the patient. Selective fusions, when successfully performed, will optimize mobile segments of the spine in patients with adolescent idiopathic scoliosis.

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°–158°; average, 84°), major compensatory coronal curve magnitude (range, 8°–123°; average, 51°), major sagittal curve magnitude (range, 13°–143°; average, 78°), 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° 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° for major coronal curves and 4° 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.

Traumatic lesions of the occipitoatlantoaxial complex

Injuries of the occipitoatlantoaxial complex are relatively rare but form a group of ligamentous and bony lesions that may unnecessarily confuse the clinician. Since fractures of the dens and traumatic spondylolisthesis of the axis have been well described in a number of large series, this article concentrates on the lesions less frequently seen and described. The ligamentous injuries are occipitoatlantal dislocation, rupture of the transverse ligament, and atlantoaxial rotatory fixation. The bony injuries are fractures of the occipital condyles, atlas, and the lateral masses of C2. The incidence, diagnostic criteria, and treatment modalities depend on the nature of localization of the traumatic lesions.

The pros and cons to saving the L5-S1 motion segment in a long scoliosis fusion construct.

Study Design. This is a review of the literature and personal experience as it pertains to whether a long fusion should be stopped at L5 or S1 in a patient with adult lumbar scoliosis and degenerative changes. Objectives. To summarize the problems with decision-making and to point out the strengths and limitations of past studies. Summary of Background Data. There is a paucity of data on this subject. Problems with stopping at L5 include fixation at that segment and subsequent breakdown at L5–S1. The problems with stopping at the sacrum include the additional surgical requirements and increased potential for pseudarthrosis. Methods. Summarized is past literature and, to some extent, personal experience of the author(s). Results. There are situations where it is clearly preferable to stop at the sacrum. However, there are many borderline circumstances in which whether it is better to stop at L5 or the sacrum is not clear cut. Conclusions. The answer to this question requires further study. Multicenter data collection, consistency of approach, and potential randomization in a prospective fashion might help provide an answer.

Radiographic markers in spondyloptosis: Implications for spondylolisthesis progression

Study Design. Radiographic analysis of spinopelvic morphology and posterior element dysplasia in spondyloptosis. Summary of Background Data. Spondylolisthesis treatment protocols are based on age, symptomatology, and slippage degree. Spinopelvic morphology and dysplasia can determine progression. Frequency of two denominators of high-grade spondylolisthesis—degree of dysplasia and spinopelvic morphology—is unknown. Objectives. To determine common radiographic denominators of spondyloptosis—degree of posterior bony hook dysplasia and spinopelvic morphology—as prognostic factors for spondylolisthesis progression. Methods. Patients with spondyloptosis were reviewed. Bony dysplasia at lumbosacral junction was graded. Pelvic incidence and sacral kyphosis were measured. Results. A total of 53 patients had a mean sacral kyphosis of 56° and pelvic incidence of 76°; 62% of patients had posterior element dysplasia. Conclusion. Prognostic factors for spondylolisthesis progression, such as percent of slippage, do not identify lower-grade slips at risk for progression. Progression is linked to increased shear stress across the lumbosacral junction and inability to resist it. Increased stress is related to increased verticality of the lumbosacral joint, which is individually predetermined by pelvic incidence and sacral anatomy. Pelvic incidence is fundamental in determining sagittal spine curvature required for economic spinopelvic balance. Pelvic incidence is independent of adaptive changes in higher-grade spondylolisthesis. Pelvic incidence in our spondyloptosis series (76°) is higher than in normal (48.2–53.2°) and low-grade spondylolisthesis (64.5°). Posterior element dysplasia decreases mechanical resistance to lumbosacral shear stress. Incidence of dysplasia in our series (62%) is higher than that reported in low-grade spondylolisthesis. Analysis of pelvic incidence and posterior element dysplasia may aid in estimation of risk for progression of spondylolisthesis.