Combined anterior and posterior fusion for Scheuermann's kyphosis

A Novel Surgical Indication for Scheuermann's Kyphosis

Scheuermann kyphosis can be treated surgically to restore proper sagittal alignment. Thoracic curves >70° are typically indicated for surgical intervention. However, patients who have reached their natural limit of compensatory lumbar hyperlordosis are at risk of accelerated degeneration. This can be determined by comparing lumbar lordosis on standing neutral radiographs and supine extension radiographs. Minimal additional lordosis in extension compared with neutral, abutment of the spinous processes, or greater lumbar lordosis standing than with attempted extension suggest the patient is maximally compensated. We present a case of an adolescent boy with Scheuermann kyphosis who had reached the limit of his hyperlordosis compensation reserve. He subsequently underwent a T4 to L2 posterior spinal fusion with T7 to T11 Ponte Smith-Petersen grade two osteotomies. He tolerated the procedure well with no intraoperative complications or neuromonitoring changes. The patient has continued to do well and progressed to normal activity at 5-month follow-up.

Scheuermann Kyphosis: Current Concepts and Management

PURPOSE OF REVIEW

Scheuermann's kyphosis (SK) is a developmental deformity of the spine that affects up to 8% of children in the US. Although, the natural progression of SK is noted to be gradual over years, severe deformity can be associated with significant morbidity. Thorough clinical examination and interpretation of relevant imaging help differentiate and confirm this diagnosis. Treatment includes both operative and nonoperative approaches. The purpose of this article is to provide an updated overview of the current theories of its pathogenesis, as well as the principles of diagnosis and treatment of SK.

RECENT FINDINGS

Although a definitive, unified theory continues to be elusive, numerous reports in the past decade provide insight into the pathophysiology of SK. These include alterations in mechanical stress and/or hormonal disturbances. Candidate genes have also been identified to be linked to the inheritance of SK. Updates to nonoperative treatment include the effectiveness of dedicated exercise programs, as well as the types and duration of orthotic treatment. Advances in surgical technique can be observed with a trend toward a posterior-only approach, with supporting evidence for careful evaluation of both the sagittal and coronal planes to determine fusion levels in order to avoid postoperative junctional pathologies. SK is an important cause of structural or rigid kyphosis. It can lead to significant morbidity in severe cases. Treatment is based on curve magnitude and symptoms. Nonoperative treatment consists of physical therapy in symptomatic patients, and bracing can be added for skeletally mature patients. Operative management can be considered in patients with large, progressive, and symptomatic deformity. Future studies can benefit from a focused investigation into patient-reported outcomes after undergoing appropriate treatment.

Long-term results of surgical correction of Scheuermann’s kyphosis

Objective. To analyze long-term results of surgical correction of kyphosis due to Scheuermann’s disease.

Material and Methods. Design: retrospective cohort study. The study group included 43 patients (m/f ratio, 34/9). The mean age was 19.1 (14–32) years; the mean postoperative follow-up was 6 ± 10 (5–20) years. Two-stage surgery including discectomy and interbody fusion followed by posterior correction and fusion was conducted in 35 cases (Group A). Eight patients (Group B) underwent only posterior correction and spinal fusion. The following parameters were determined for each patient: thoracic kyphosis (TK), lumbar lordosis (LL) (scoliotic deformity of the thoracic/thoracolumbar spine, if the curve magnitude was > 5°), sagittal vertical axis (SVA), sagittal stable vertebra (SSV), first lordotic vertebra (FLV), proximal junctional angle (PJA) and distal junctional angle (DJA). All measurements were performed immediately before surgery, one week after surgery, and at the end of the follow-up period. All patients answered the SRS-24 questionnaire after surgery and at end of the follow-up period.

Results. Groups were comparable in terms of age and gender of patients, body mass index and initial Cobb angle (p < 0.05). The curve decreased from 77.8° to 40.7° in Group A and from 81.7° to 41.6° in Group B. The loss of correction was 9.1° and 6.0° in groups A and B, respectively. The parameters of lumbar lordosis remained normal during the follow-up period. At implant density less than 1.2, deformity correction and correction loss were 44.5° (54.7 %) and 3.9°, respectively (p < 0.05). Proximal junctional kyphosis (PJK) was detected in 21 out of 43 patients (48.8 %). The frequency of PJK was 45.4 % among patients whose upper end vertebra was included in the fusion and 60 % among those whose upper end vertebra was not included. PJK developed in eight (47.8 %) out of 17 patients with kyphosis correction ≥ 50 % and in 13 (50.0 %) of those with correction < 50 %. The rate of DJK development was 39.5 %. The lower instrumented vertebra (LIV) was located proximal to the sagittal stable vertebra in 16 cases, with 12 (75 %) of them being diagnosed with DJK. In 27 patients, LIV was located either at the SSV level or distal to it, the number of DJK cases was 5 (18.5 %); p < 0.05. Only two patients with complications required unplanned interventions. According to the patient questionnaires, the surgical outcome score increases between the immediate and long-term postoperative periods for all domains and from 88.4 to 91.4 in total. The same applies to answer to the question about consent to surgical treatment on the same conditions: positive answers increased from 82 to 86 %.

Conclusions. Two-stage surgery, as a more difficult and prolonged one, has no advantages over one-stage operation in terms of correction magnitude and stability of the achieved effect. Surgical treatment improves the quality of life of patients with Scheuermann’s disease, and the improvement continues in the long-term postoperative period.

Long-term outcome after surgical treatment of Scheuermann's Kyphosis (SK)

STUDY DESIGN

A retrospective observational cohort study with a minimum follow-up of 10 years of patients who underwent surgery for Scheurmann Kyphosis (SK).

OBJECTIVE

Evaluate the long-term clinical and radiological outcome of patients with SK who either underwent combined anterior-posterior surgery or posterior instrumented fusion alone. There is paucity of literature for long-term outcome studies on SK. The current trend is towards only posterior (PSF) surgical correction for SK. The combined strategy of anterior release, fusion and posterior spinal fusion (AF/PSF) for kyphosis correction has become historic relic. Long-term outcome studies comparing the two procedures are lacking in literature.

METHODS

51 patients (30 M: 21F) who underwent surgery for SK at a single centre were reviewed. Nineteen had posterior instrumentation alone (PSF) (Group 1) and 32 underwent combined anterior release, fusion with posterior instrumentation (AF/PSF) (Group 2). The clinical data included age at surgery, gender, flexibility of spine, instrumented spinal levels, use of cages and morcellised rib grafts (in cases where anterior release was done), posterior osteotomies and instrumentation, complications and indications for revision surgery. Preoperative flexibility was determined by hyperextension radiographs. The radiological indices were evaluated in the pre-operative, 2-year post-operative and final follow-up [Thoracic Kyphosis (TK), Lumbar lordosis (LL), Voustinas index (VI), Sacral inclination (SI) and Sagittal vertical axis (SVA)]. The loss of correction and incidence of JK (Junctional Kyphosis) and its relation to fusion levels were assessed. Complications and difference in outcome between the two groups were analyzed.

RESULTS

The mean age at surgery for 51 patients was 20.6 years who were followed up for a minimum of 10 years (mean: 14 years; range 10-16 years). The mean age was 18.5 ± 2.2 years and 21.9 ± 4.8 years in groups 1 and 2, respectively. The mean pre- and 2-year post-operative ODIs were 32.6 ± 12.8 and 8.4 ± 5.4, respectively, in group 1 (p < 0.0001) and 30.7 ± 11.7 and 6.4 ± 5.7, respectively, in group 2 (p < 0.0001). The final SRS-22 scores in group 1 and 2 were 4.1 ± 0.4 and 4.0 ± 0.35, respectively (p = 0.88). The preoperative flexibility index was 49.2 ± 4.2 and 43 ± 5.6 in groups 1 and 2, respectively (p < 0.0001). The mean TKs were 81.4° ± 3.8° and 86.1° ± 6.0° for groups 1 and 2, respectively, which corrected to 45.1° ± 2.6° and 47.3° ± 4.8°, respectively, at final follow-up (p < 0.0001). The mean pre-operative LL angle was 60.0° ± 5.0° and 62.4° ± 7.6° in groups 1 and 2, respectively, which at final follow-up was 45.1° ± 4.4° and 48.1° ± 4.8°, respectively (p < 0.0001). The mean pre-operative and final follow-up Voustinas index (VI) in group 1 were 22.9 ± 2.9 and 11.2 ± 1.2, respectively, and in group 2 was 25.9 ± 3.5 and 14.0 ± 2.3, respectively. The mean pre-operative and final follow-up SI angle were 43.6° ± 3.3° and 31.2° ± 2.5° in group 1, respectively, and 44.3° ± 3.5° and 32.1° ± 3.5° in group 2, respectively (p < 0.0001). The pre-operative and final follow-up SVA in group 1 were - 3.3 ± 1.0 cms and - 1.3 ± 0.5 cms, respectively, and in group 2 was - 4.0 ± 1.3cms and - 1.9 ± 1.1cms, respectively (p < 0.0001). Though the magnitude of curve correction in the groups 1 and 2 was significant 36° vs 39° (p = 0.05), there was no significant difference in correction between the two groups. Proximal JK was seen in seven and distal JK in five patients were observed in the whole cohort.

CONCLUSION

The long-term clinical outcomes for both PSF and AF/PSF are comparable with reproducible results. No difference was noted in loss of correction and outcome scores between the two groups. The correction of thoracic kyphosis (TK) had a good correlation with ODI. AF/PSF had much higher complications than PSF group. The objective of correcting the sagittal profile and balancing the whole spinal segment on the pelvis can be achieved through single posterior approach with fewer complications.

Curve patterns deserve attention when determining the optimal distal fusion level in correction surgery for Scheuermann kyphosis

BACKGROUND CONTEXT

The surgical strategy to decide distal fusion level for Scheuermann kyphosis (SK) is controversial. Some spinal surgeons advocate that instrumentation should end at the first lordotic vertebra (FLV), whereas others recommend extending spinal fusion to the sagittal stable vertebra (SSV). Scheuermann kyphosis has two curve patterns: Scheuermann thoracic kyphosis (STK), with the curve apex above or at T10; and Scheuermann thoracolumbar kyphosis (STLK), with the curve apex below T10. To our knowledge, curve patterns have not been taken into consideration when determining the distal fusion level.

PURPOSE

This study aims to analyze the clinical and radiographic outcomes, including the distal junctional problems, in pediatric patients with STK and STLK who underwent fusion with different distal fusion levels.

STUDY DESIGN

This is a retrospective, single-center, institutional review board-approved study.

PATIENT SAMPLE

A total of 45 consecutive pediatric patients with STK or STLK.

OUTCOME MEASURES

The following parameters were evaluated: global kyphosis (GK), deformity angular ratio (DAR), correction rate of GK and DAR, thoracolumbar kyphosis (TLK), lumbar lordosis (LL), sagittal vertical axis (SVA), T1 pelvic angle (TPA), the distance from the center of the lower instrumented vertebra (LIV) to the posterior sacral vertical line, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and distal junctional kyphosis (DJK).

METHODS

This work was supported by the National Natural Science Foundation of China (Grant No. 81171672), Nanjing Clinical Medical Center, and Jiangsu Provincial Key Medical Center. Patients with STK were fused to SSV at the distal level (Group STK), whereas patients with STLK were fused to FLV (Group STLK). Whole spine x-rays obtained before surgery, immediately after operation, and at the latest follow-up were evaluated. The radiographic and clinical data were compared between Groups STK and STLK. All patients had a minimum of 2 years of follow-up.

RESULTS

Before surgery, Groups STK and STLK were comparable in terms of age, gender, body mass index, fusion levels, follow-up time, some radiographic parameters and the 22-item Scoliosis Research Society questionnaire (SRS-22) evaluation. DAR and TLK were significantly smaller, whereas PI was significantly greater, in Group STK than those in Group STLK. Despite different distal fusion strategies, STK and STLK were corrected to an equivalent extent, with similar GK, correction rate, LL, SVA, TPA, PT, and SS immediately after operation and at the final follow-up. The DAR and TLK retained were smaller, whereas the PI retained was greater, in Group STK than STLK after surgery. Distal junctional kyphosis complications were found in five patients with STK curve type. In Group STK, patients with DJK were found to have significantly larger preoperative GK (87.5±7.0 vs. 77.5±9.0, p=.024), correction rate of GK (62.9±10.2% vs. 51.3±8.5%, p=.021), and correction rate of DAR (55.9±4.5% vs. 36.6±13.7%, p=.011) than those without DJK. Pre- and postoperative SRS-22 assessments did not show any significant difference between Groups STK and STLK or between patients with and without DJK.

CONCLUSIONS

Curve patterns should be taken into attention when determining the optimal distal fusion level in correction surgery for SK. For patients with STLK, relatively shorter fusion stopping at FLV is enough to correct SK with the preservation of more lumbar motility and less development of DJK. For patients with STK, we suggest extending fusion to the SSV, which could restrict more distal junctional problems than fusion to the FLV. Large GK and correction degree might be the associated factors of developing DJK in STK patients.

Scheuermann's Kyphosis: Diagnosis, Management, and Selecting Fusion Levels

Scheuermann's kyphosis (SK) is a rigid structural deformity of the thoracic spine defined radiographically as three or more contiguous vertebrae with at least 5° of wedging anteriorly. Prevalence of the disease is thought to be between 0.4% and 10%. The true cause of SK remains unclear; however, various theories include growth irregularities, mechanical factors, genetic factors, and/or poor bone quality as the causes. Patients with mild disease (less than 70°) generally have a favorable prognosis with good clinical outcomes. Most patients with SK are successfully treated nonsurgically with observation, anti-inflammatory medications, and physical therapy. Surgical intervention is indicated in patients with greater than 70° to 75° thoracic curves, greater than 25° to 30° thoracolumbar curves, intractable pain, neurologic deficit, cardiopulmonary compromise, or poor cosmesis. Because of advances in posterior spinal instrumentation, surgery can typically be performed through a posterior-only approach. When surgical treatment is planned, appropriate selection of the upper- and lower-instrumented vertebrae is important to achieve a well-balanced spine, preserve motion segments, and reduce the risk of junctional kyphosis.

Selection of distal fusion level in terms of distal junctional kyphosis in Scheuermann kyphosis. A comparison of 3 methods

Objective

The aim of this study was to investigate the effect of distal fusion level selection on the distal junctional kyphosis (DJK) in Scheuermann kyphosis (SK) patients who underwent posterior fusion.

Methods

Thirty-nine SK patients who underwent posterior fusion with a minimum follow-up of 3 years were retrospectively evaluated. According to the distal fusion level, patients were divided into 3 groups. Group S; lowest instrumented vertebra (LIV) was the sagittal stable vertebra (SSV), Group F; LIV was the first lordotic vertebra (FLV) and, Group L; LIV was the lower end vertebra (LEV). DJK was evaluated according to distal level selection.

Results

Thoracic kyphosis (TK) decreased from 73.3° (SD ± 7.9°) to 39° (SD ± 8.7°) postoperatively, with a mean correction rate of 46% (SD ± 13) (p < 0.0001). In 11 patients, FLV and SSV was the same vertebra. In remaining 28 patients, 10 patients were in Group S, 15 patients were in Group F and 3 patients were in Group L. In Group S, none of them developed DJK, however, DJK was observed 9 of 15 patients in Group F. DJK was developed in all cases in Group L. There is a statistically higher risk for developing DJK when FLV or LEV was selected as LIV (p < 0.05).

Conclusion

Selecting SSV for the distal fusion level has been found to be effective for preventing DJK. Selecting distal fusion level proximal to SSV will increase the risk of DJK which may become symptomatic and require revision surgery.

Level of evidence

Level IV, therapeutic study.

Selection Of The Optimal Level Of Distal Fixation For Correction Of Scheuermann's Hyperkyphosis

OBJECTIVE

To analyze the efficacy of the method for selecting the distal level of fusion in treatment of thoracic hyperkyphosis in patients with Scheuermann's disease.

BACKGROUND

The fusion area needs to include all the kyphotic deformity in Scheuermann patients; however, precise levels of the distal fixation have not been determined yet.

STUDY DESIGN

Retrospective cohort review.

MATERIALS AND METHODS

Thirty-six patients were operated in the Department of Children and Adolescent Spine Pathology between 2007 and 2010. These patients were divided into two groups: in group I (n = 29) a lower instrumented vertebra corresponded to the sagittal stable one and in group II (n = 7) - this vertebra located proximally.

RESULTS

The mean preoperative kyphosis was 79.3° ± 11.6°, the postoperative - 40.6° ± 11.9° (correction of 49.9%), loss of correction was 4.9° ± 7.0°. Sagittal balance changed from -0.3 ± 3.2 cm before surgery to -1.7 ± 2.1 cm after surgery. Distal junctional kyphosis developed in 1 case (4%) in Group I, and in 5 cases (71%) in Group II.

CONCLUSION

A distal level of instrumentation ending at the first lordotic vertebra is not justified and causes violation of sagittal balance and development of distal junctional kyphosis. The inclusion of a sagittal stable vertebra in fusion prevents the development of this undesirable situation.

Comparison of Scheuermann's kyphosis correction by combined anterior-posterior fusion versus posterior-only procedure

INTRODUCTION

Conventional treatment of rigid deformity in Scheuermann's kyphosis (SK) in young patients includes a preliminary anterior spinal release and fusion (ASF) followed by posterior spinal fusion and instrumentation (PSF). However, recently there are more trends to do posterior-only surgery for correction of this deformity. The aim of our study was to compare clinical and radiological outcomes of ASF/PSF and PSF-only procedures in treatment of SK.

MATERIALS AND METHODS

In a prospective clinical and radiological review, thirty operated SK patients in two groups were evaluated. Group A: ASF/PSF technique (n: 16) and group B: PSF-only procedure (n: 14) were followed for at least 2 years (average 57.6 months). Two groups were well matched for the following four criteria: average age, flexibility status, posterior fusion levels, and preoperative Cobb's kyphosis angle. Oswestry disability index (ODI) and scoliosis research society questionnaire-30 (SRS-30) and radiological (kyphosis correction, correction loss, sagittal balance) parameters were evaluated before and after surgery and at the final follow-up.

RESULTS

In group A, primary thoracic Cobb's kyphosis, immediate post-operative kyphosis, and final follow-up kyphosis angle were 83.6°, 41.4° and 43°, respectively (P < 0.05). Correction rate and correction loss were 50.5 % and 1.6° ± 2.4, respectively. In group B, the corresponding values were 81.9°, 40.1° and 43.2°, respectively (P < 0.05). Correction rate and correction loss were 51 % and 3.1° ± 2.5, respectively. SRS-30 and ODI scores in group A were averaged 68.5 and 21.3 preoperatively and 128.7 and 6.25 at the final follow-up, respectively. In group B, the corresponding values were 64 and 23.2 preoperatively and 133.5 and 5.8 at the final follow-up, respectively.

CONCLUSIONS

Clinical and radiological parameters were similar in both groups after surgical correction while, complication rates, operation time and blood loss were significantly higher in ASF/PSF procedure.

National Trends in Spinal Fusion Surgery For Scheuermann Kyphosis

STUDY DESIGN

Analysis of a national database.

OBJECTIVE

To analyze national trends in spinal fusion surgery for Scheuermann kyphosis (SK) and to compare surgical approaches used in treatment.

SUMMARY OF BACKGROUND DATA

The preferred surgical approach for treating SK is not well established. Recent studies support the use of posterior spinal fusion (PSF) instead of anterior-posterior spinal fusion (APSF).

METHODS

Using the Nationwide Inpatient Sample database, we identified 2,796 patients (mean age, 24.9 years; 66% men) from 2000 to 2008 who had spinal fusion surgery for SK. We compared the two approaches with respect to patient demographics, institutional characteristics, in-hospital complications, and hospitalization lengths and costs. Significance was set at a value of p less than .05.

RESULTS

The number of spinal fusion surgeries performed in patients with SK increased significantly (p = .03). The proportion of patients undergoing surgery as adults also increased significantly (p < .05). The number of PSF surgeries performed in patients with SK increased 2.9-fold (34% to 78%) (p < .01); APSF use declined by 7% per year. There was no significant association among surgical approach and patient age, sex, hospital capacity, or teaching status. Compared with patients undergoing PSF, patients undergoing APSF had 2.1-fold more in-hospital complications (p < .01), 3.8-fold more pulmonary complications (p < .01), 2.7-fold more renal complications (p < .01), and significantly longer hospitalizations (mean, 8.5 days vs. 5.9 days, respectively; p < .01). There was no significant difference in mean total hospital charges: $117,921 for APSF and $119,322 for PSF.

CONCLUSION

There have been significant increases in the number of spinal fusion surgeries for SK, and in the proportion of patients with SK who are choosing surgery as adults. Surgical treatment has shifted predominantly toward an all-posterior approach. PSF is associated with lower complication rates (especially pulmonary complications) and shorter hospitalizations.

[Current concepts on Scheuermann kyphosis: clinical presentation, diagnosis and controversies around treatment]

Scheuermann kyphosis is a structural deformity of the thoracic or thoracolumbar spine that develops prior to puberty and deteriorates during adolescence. There is limited information on its natural history but many patients are expected to have a benign course. Severe kyphosis can progress into adult life and cause significant deformity and debilitating back pain. Conservative treatment includes bracing and physical therapy, but although widely prescribed they have not been scientifically validated. Surgical treatment may be considered in the presence of a progressive kyphosis producing severe pain resistant to conservative measures, neurological compromise, or unacceptable deformity. This is associated with significant risks of major complications that should be discussed with the patients and their families. Modern techniques allow better correction of the deformity through posterior-only surgery with lower complication rates. Simultaneous shortening of the posterior vertebral column across the apical levels, along with spinal cord monitoring, reduces the risk of neurological deficits.

What is the best way to optimize thoracic kyphosis correction? A micro-CT and biomechanical analysis of pedicle morphology and screw failure

STUDY DESIGN

A human cadaveric biomechanical analysis.

OBJECTIVE

The purpose of this study was to evaluate the bone density/trabecular width of the thoracic pedicle and correlate that with its resistance against compressive loading used during correction maneuvers in the thoracic spine (i.e., cantilever bending).

SUMMARY OF BACKGROUND DATA

As surgeons perform cantilever correction maneuvers in the spine, it is common to have pedicle screws pullout or displace while placing corrective forces on the construct. Currently, surgeons either compress against the cephalad aspect of the pedicle or vice versa. We set out to establish which aspect of the pedicle was the most dense and to determine the optimal direction for screw compression during kyphosis/deformity correction.

METHODS

Fifteen fresh-frozen cadaveric vertebrae (n = 15) were examined by micro-computed tomography to determine percent bone volume/total volume (%BV/TV) within the cephalad and caudad aspects of the pedicle. Specimens were sectioned in the sagittal plane. Pedicles were instrumented according to the straightforward trajectory on both sides. Specimens were then mounted and loading to failure was performed perpendicular to the screw axis (either the cephalad or the caudad aspect of the pedicle).

RESULTS

Mean failure when loading against the caudad aspect of the pedicle was statistically, significantly greater (454.5 ± 241.3 N vs. 334.79 1 ± 158.435 N) than for the cephalad pedicle (P < 0.001). In concordance with failure data, more trabecular and cortical bones were observed within the caudad half of the pedicle compared with the cephalad half (P < 0.001).

CONCLUSION

Our results suggest that the caudad half of the pedicle is denser and withstands higher forces compared with the cephalad aspect. In turn, the incidence of intraoperative screw loosening and/or pedicle fracture may be reduced if the compressive forces (cantilever bending during deformity correction) placed upon the construct are applied against the caudad portion of the pedicle.

SCHEUERMANN'S KYPHOSIS: COMPARISON BETWEEN THE POSTERIOR APPROACH ASSOCIATED WITH SMITH-PETERSEN OSTEOTOMY AND COMBINED ANTERIOR-POSTERIOR FUSION

OBJECTIVE

Surgical treatment of Scheuermann's kyphosis (SK) remains a subject under discussion. In view of the controversy over the best form of surgical tr otomy.

METHODS

This was a descriptive case-control study with cross-sectional analysis. Twenty-eight patients, split into two groups conducted at different times, were evaluated.

RESULTS

The first group comprised patients treated using the double approach, with an average age of 19 years, preoperative kyphosis of 77.6°, postoperative kyphosis of 35.8° and average correction of 53.2%. The second group comprised patients treated using the posterior route associated with Smith-Petersen osteotomy, with a mean age of 27.3 years, preoperative kyphosis of 72.9°, postoperative kyphosis of 44.3° and average correction of 39.3%. Analysis between the two groups showed statistically significant differences in the following variables: age (p = 0.02), postoperative kyphosis (p = 0.04) and degree and percentage of kyphosis correction (p = 0.001). There was no difference concerning preoperative kyphosis (p = 0.33). In the assessment of postoperative pain (VAS), the first group presented an average of 0.6, versus 0.5 in the second group. There were only minor complications: seven in the first group and two in the second.

CONCLUSION

The two surgical techniques studied proved to be adequate for treating SK. In the present study, the deformity correction was greater in the first group, while the pain VAS results were better in the second group, with lower incidence of complications.

Do discs "open" anteriorly with posterior-only correction of Scheuermann's kyphosis?

STUDY DESIGN

Retrospective radiographic analysis.

OBJECTIVE

To investigate where and to what degree the correction of Scheuermann's kyphosis occurred in two different procedures: posterior instrumentation/fusion with an anterior release and posterior-only instrumentation/fusion with Ponte procedure.

SUMMARY OF BACKGROUND DATA

Controversy remains regarding the outcome for these two procedures. The postoperative segmental disc shape change that account for deformity correction has not been described for either procedure.

METHODS

Eleven patients undergoing a thoracoscopic anterior release followed by posterior instrumentation (A + P) and 11 patients having posterior-only (PO) instrumentation/fusion were retrospectively reviewed. In addition to conventional Cobb measurements, segmental measures of intradiscal angulation as well as anterior and posterior disc heights were made before and after surgery.

RESULTS

The thoracic hyperkyphosis was corrected to similar degrees in both groups (A + P vs. PO, P = 0.87). The PO group averaged 82.7° ± 6.4° before surgery and corrected to 47.9° ± 5.4° after surgery; while the A + P group averaged 84.9° ± 10.2° before surgery and corrected to 48.6° ± 5.7° after surgery. The segmental analysis demonstrated similar degrees of intradiscal angular changes between the two surgical procedures. The majority of the correction occurred at and below the apex and was independent of an anterior release. The changes in both anterior and posterior disc thicknesses were also similar between the two groups. Both groups' anterior disc spaces opened at T8 and below, whereas maximum anterior disc opening occurred at the thoracolumbar junction. To a lesser extent, the posterior disc heights were reduced, but also to similar degrees for both surgical approaches.

CONCLUSION

For both surgical procedures, the majority of the kyphosis correction occurred in the lower thoracic levels and anterior disc heights increased up to twice as much as posterior disc heights shortened. The addition of the anterior release did not significantly alter the degree of correction or the disc shape changes.

[Correction of adolescent kyphosis. What is the state of the art?]

Thoracic and thoracolumbar kyphosis is a common deformity in pediatric and adolescent populations. Kyphotic deformation of the spine is defined as a curve which shows an increase in the dorsal convex angulation. The most common causes of kyphosis in pediatric and adolescent populations are Scheuermann's disease, postural and congenital kyphosis. The fundamental principles of treatment are analysis of the kyphotic deformity and restoration or maintenance of sagittal balance. Clinically significant sagittal deformities can lead to severe pain, substantial cosmetic alterations, spinal cord dysfunction, problems with swallowing, gastrointestinal and cardiopulmonary complications. When the kyphotic deformity exceeds a certain point and conservative therapy options are no longer sufficient surgical intervention is indicated. The available operative options for treatment of the various types of pediatric and adolescent thoracolumbar kyphosis include dorsal instrumentation and fusion combined with ventral fusion and purely ventral instrumentation and fusion.

Scheuermann’s kyphosis; current controversies

This review of the literature presents the current understanding of Scheuermann’s kyphosis and investigates the controversies concerning conservative and surgical treatment. There is considerable debate regarding the pathogenesis, natural history and treatment of this condition. A benign prognosis with settling of symptoms and stabilisation of the deformity at skeletal maturity is expected in most patients. Observation and programmes of exercise are appropriate for mild, flexible, non-progressive deformities. Bracing is indicated for a moderate deformity which spans several levels and retains flexibility in motivated patients who have significant remaining spinal growth.

The loss of some correction after the completion of bracing with recurrent anterior vertebral wedging has been reported in approximately one-third of patients. Surgical correction with instrumented spinal fusion is indicated for a severe kyphosis which carries a risk of progression beyond the end of growth causing cosmetic deformity, back pain and neurological complications. There is no consensus on the effectiveness of different techniques and types of instrumentation. Techniques include posterior-only and combined anteroposterior spinal fusion with or without posterior osteotomies across the apex of the deformity. Current instrumented techniques include hybrid and all-pedicle screw constructs.

Correção da cifose de Scheuermann: estudo comparativo da fixação híbrida com ganchos e parafusos versus fixação apenas com parafusos

OBJETIVOS: avaliar o grau de correção da cifose de Scheuermann, em 6 pacientes que se submeteram à instrumentação híbrida composta por ganchos e parafusos (H) e 17 fixados apenas com parafusos (P). MÉTODOS: 23 pacientes, com cifose de Scheuermann, submetidos a tratamento cirúrgico por dupla via com início pela via anterior, seguido pela via posterior. Do conjunto de pacientes, 6 foram operados com fixação híbrida e 17 com uso exclusivo de parafusos pediculares. O tratamento cirúrgico foi indicado para cifose rígida, variando de 60º e 105º e portadores do sinal de Risser acima de 4. RESULTADOS: observou-se, no Grupo H, cifose pré-operatória média de 84,17º e no pós-operatório de 47,5º. No Grupo P, a média de cifose no pré-operatório era de 80,35º e, no pós-operatório, de 33,53º. CONCLUSÃO: concluiu-se que os dois tipos de fixação apresentaram resultados muito satisfatórios, contudo, sendo ainda superior quando fixados só com parafusos.

Selection of the optimal distal fusion level in posterior instrumentation and fusion for thoracic hyperkyphosis: the sagittal stable vertebra concept

STUDY DESIGN

Retrospective study.

OBJECTIVE

To determine the appropriate distal fusion level in posterior instrumentation and fusion for thoracic hyperkyphosis by investigating the relationship between the sagittal stable vertebra ([SSV]-the most proximal lumbar vertebral body touched by the vertical line from the posterior-superior corner of the sacrum), first lordotic vertebra (just caudal to the first lordotic disc), and selected lowest instrumented vertebra (LIV).

SUMMARY OF BACKGROUND DATA

It has been recommended that the distal end vertebra and the first lordotic disc beyond the transitional zone distally be included in distal fusion for thoracic hyperkyphosis; however, we have seen distal junctional breakdown even when these rules have been followed.

METHODS

Thirty-one patients (mean age: 18 years, range: 13-38) who underwent long posterior instrumentation and fusion for thoracic hyperkyphosis with a minimum 2-year follow-up were reviewed. Preoperative diagnoses included Scheuermann kyphosis (n = 29), post-traumatic kyphosis (n = 1), and postlaminectomy kyphosis (n = 1). According to the distal fusion level, patients were divided into 2 groups. Group I (n = 24): LIV included the SSV; group II (n = 7): the LIV was proximal to the SSV. Patients were evaluated using standing radiographs and chart review.

RESULTS

Preoperative mean thoracic kyphosis was 86.6 +/- 8.5 degrees and 53.0 +/- 10.4 degrees at final follow-up with a correction rate of 39%. Preoperative average sagittal balance was slightly negative (-0.24 +/- 3.8 cm), and became slightly more negative (-1.33 +/- 2.8 cm) by final follow-up. There were no statistical differences in thoracic kyphosis between the 2 groups. However, there was a statistically significant difference with group II having a more posterior translation of the center of the LIV from the posterior sacral vertical line before surgery and at final follow-up (P = 0.003). In group I, distal junctional problems developed in 2 of 24 (8%) patients and in group II, problems occurred in 5 of 7 (71%) patients (P < 0.05). Despite extending the fusion to the first lordotic vertebra, distal junctional problems developed in 3 of 8 (38%) patients.

CONCLUSION

The distal end of a fusion for thoracic hyperkyphosis should include the SSV. Levels that include the first lordotic vertebra but not the SSV are not always appropriate to prevent postoperative distal junctional kyphosis.

All pedicle screw instrumentation for Scheuermann's kyphosis correction: is it worth it?

BACKGROUND CONTEXT

Scheuermann's kyphosis has long been treated by a two-staged fusion and instrumentation with a hybrid construct using hooks, pedicle screws, and sublaminar wires. Recent interest in all pedicle screw constructs led to its use in the treatment of Scheuermann's kyphosis. Evaluation of this newly described application is needed.

PURPOSE

To compare the results of segmental all pedicle screw constructs versus two-staged hybrid instrumentation in patients with Scheuermann's kyphosis analyzing the amount of correction and incidence of complications.

STUDY DESIGN

Retrospective case series reporting on two groups of patients with Scheuermann's kyphosis treated with single-staged all pedicle screws technique versus two-staged anterior release and posterior hybrid instrumentation followed-up for a minimum of 2 years.

PATIENT SAMPLE

The study included 33 patients divided into two groups. The average age was 15 years+9 months and 16 years+8 months, respectively. The average preoperative dorsal kyphosis was 85.5 degrees (Group 1) and 79.8 degrees (Group 2).

OUTCOME MEASURES

The deformity was measured by Cobb's method preoperatively, postoperatively, and at final follow-up. Operative time and blood loss were also measured and recorded. The results of the Scoliosis Research Society (SRS)-30 questionnaire were also reviewed.

METHODS

The study included 16 patients who underwent a single-staged correction by segmental all pedicle screw constructs and multiple-level posterior osteotomies (Group 1) and 17 who underwent a two-staged fusion and instrumentation with a hybrid construct (Group 2).

RESULTS

Both groups were followed for a minimum of 2 years. The deformity correction of Group 1 had an average of 52.2% postoperatively with 2.4% loss at final follow-up in comparison to Group 2 where the correction was 48.7% postoperatively with 3.1% loss at final follow-up. The operative time was considerably less in Group 1 with an average of 215 minutes than Group 2 with an average of 315 minutes. The average blood loss was 620cc in Group 1 and 910cc in Group 2. The SRS-30 questionnaire in Group 1 averaged 134 and in Group 2 averaged 120.

CONCLUSIONS

The use of multiple-level all pedicle screws technique allowed a rigid anchor for posterior correction of the deformity with less operative time, blood loss, and hospital stay without the need for anterior release. A better correction was achieved and preserved with the use of all pedicle screw constructs. This technique is a useful modality in the treatment of Scheuermann's kyphosis.

MULTIPLE SEGMENTAL OSTEOTOMIES TO THE KYPHOSIS CORRECTION

OBJECTIVE

To evaluate the results of the surgical treatment of the spinal Kyphosis using the Ponte's technique (multiple posterior osteotomies).

METHODS

Ten patients (8 with Scheuermann's kyphosis and 2 with kyphosis after laminectomy) submitted to surgical correction of kyphotic deformity greater than 70° were retrospectively assessed. The age at the surgical time ranged from 12 to 20 years old (mean age16.8 years ± 2.89). The radiographic parameters evaluated were the kyphosis, the lordosis and the scoliosis - whenever present. The presence of proximal and distal junctional kyphosis, loss of correction, and complications as implants loosening and breakage were also assessed. The radiographic parameters were evaluated at the preoperative, early postoperative and late postoperative time.

RESULTS

The patients were followed through a period that ranged from 24 to 144 months (65.8 ±39.92). The mean value of the kyphosis was 78.8° ± 7.59° (Cobb) before surgery and 47.5° ± 12.54° at late follow up, with mean correction of 33.9° ± 9.53° and lost correction of 2.2°.

CONCLUSION

The surgical treatment of the thoracic kyphosis using multiples posterior osteotomies presented a good correction of the deformity and minimal lost of correction during follow up.

DECISION MAKING IN PEDIATRIC SPINAL DEFORMITY

OBJECTIVE

To review the concepts involved in the decision-making process for management of pediatric patients with spinal deformity.

METHODS

The literature was reviewed in reference to pediatric deformity evaluation and management.

RESULTS

Pediatric spinal deformity includes a broad range of disorders with differing causes, natural histories, and treatments. Appropriate categorization of pediatric deformities is an important first step in the clinical decision-making process. An understanding of both nonoperative and operative treatment modalities and their indications is requisite to providing treatment for pediatric patients with spinal deformity. The primary nonoperative treatment modalities include bracing and casting, and the primary operative treatments include nonfusion instrumentation and fusion with or without instrumentation. In this article, we provide a review of pediatric spinal deformity classification and an overview of general treatment principles.

CONCLUSION

The decision-making process in pediatric deformity begins with appropriate diagnosis and classification of the deformity. Treatment decisions, both nonoperative and operative, are often predicated on the basis of the age of the patient and the natural history of the disorder.

Cifose torácica e músculos isquiotibiais: correlação estético-funcional

OBJETIVO: Os autores discutem a correlação existente entre a cifose torácica aumentada, em pacientes portadores de Dorso Curvo Postural (DCP) ou Doença de Scheuermann (DS), e a contratura dos músculos isquiotibiais. Esta relação é pouco estudada na literatura. MÉTODOS: No período de junho a dezembro de 2003, foram analisados 38 pacientes. Dentre os pacientes, 26 (68,4 %) eram do sexo masculino e 12 (31,6%) do sexo feminino. A idade mínima foi de 10 anos e a máxima de 20 anos, com média de 15,36. Encontramos 20 (52,6%) pacientes portadores de Doença de Scheuermann e 18 (47,4%) com Dorso Curvo Postural. RESULTADOS: De todos os 38 pacientes estudados, 32 (84,2%) apresentaram contratura dos isquiotibiais, o que foi estatisticamente significante (p<0,001). Analisando apenas pacientes com DS encontramos 85% de contratura e 83,3% nos com DCP. CONCLUSÃO: Não houve diferença estatística, da porcentagem de contratura dos isquiotibiais na DS em relação ao DCP (p=0,61).

Comparison of Scheuermann kyphosis correction by posterior-only thoracic pedicle screw fixation versus combined anterior/posterior fusion

STUDY DESIGN

Retrospective comparison review.

OBJECTIVE

Compare posterior-only treatment results with segmental thoracic pedicle screw constructs versus combined anterior/posterior fusion in patients with Scheuermann kyphosis.

SUMMARY OF BACKGROUND DATA

Traditionally, operative Scheuermann kyphosis has been treated with combined anterior/posterior spinal fusion, with the anterior portion being performed via an open thoracotomy or a video-assisted thoracoscopic approach.

METHODS

There were 18 patients with Scheuermann kyphosis who underwent a posterior-only thoracic pedicle screw (P/TPS) fusion and 21 who underwent an anterior/posterior fusion who were followed for a 2-year minimum. The 2 groups were well matched according to average age (anterior/posterior fusion 18.0 degrees and P/TPS 17.3 degrees; P = 0.60), maximum preoperative kyphosis (anterior/posterior fusion 89.1 degrees and P/TPS 84.4 degrees; P = 0.21), flexibility index (anterior/posterior fusion 0.408 degrees and P/TPS 0.407 degrees; P > 0.99), and posterior fusion levels (anterior/posterior fusion 12.1 degrees and P/TPS 12.2 degrees; P = 0.95). Of 21 patients with anterior/posterior fusions, zero versus 12 of 18 (67%) patients in the P/TPS group underwent apical Smith-Petersen osteotomies. Fixation in the anterior/posterior fusion group was achieved with hybrid hook/screw constructs. Posterior fixation in the P/TPS group was performed using segmental thoracic pedicle screw constructs. Both groups had posterior iliac bone autografting. Operating time and blood loss were noted, and radiographs were evaluated before surgery, after surgery, and at final follow-up. At final follow up, Scoliosis Research Society-30 questionnaire data and complications were recorded.

RESULTS

At surgery, operating time and blood loss were significantly less in the P/TPS group (P = 0.009 and P = 0.05, respectively). The mean residual kyphosis of the P/TPS group averaged 38.2 degrees after surgery and 40.4 degrees at final follow-up versus anterior/posterior fusion group (51.9 degrees and 58.0 degrees, P < 0.001 and P = 0.001, respectively). Even without an anterior release, kyphosis correction in the P/TPS group averaged 54.2% after surgery and 51.8% at final follow-up versus the anterior/posterior fusion group (41.2% and 38.5%, P = 0.001 and P < 0.001, respectively). Scoliosis Research Society-30 outcome scores at final follow-up were comparable between the 2 groups (P/TPS = 120 and anterior/posterior fusion = 128; P = 0.14). The anterior/posterior fusion group had 8/21 (38%) patients with complications, including paraplegia in 1, proximal junctional kyphosis in 1, proximal hook pullout in 1, and infection in 2. The P/TPS group had no complications (P = 0.003).

CONCLUSIONS

With less operating time and intraoperative blood loss, posterior-only Scheuermann kyphosis treatment with thoracic pedicle screws achieved and maintained better correction, and had significantly less complications than with circumferential fusion.

Do anterior interbody cages have a potential value in comparison to autogenous rib graft in the surgical management of Scheuermann's kyphosis?

BACKGROUND CONTEXT

Previous studies have analyzed the outcome following posterior correction and combined anterior-posterior correction for Scheuermann's kyphosis. Traditionally interbody fusion has been obtained using morselized rib graft. Recently the use of titanium anterior cages has been suggested for interbody use. There are no long-term studies comparing these two techniques.

PURPOSE

To investigate the potential value of titanium anterior interbody cages compared with morselized rib graft for anterior interbody fusion in combination with posterior instrumentation, correction, and fusion for Scheuermann's kyphosis.

STUDY DESIGN

Nonrandomized comparison of two surgical techniques in matched subjects.

PATIENT SAMPLE

Fifteen patients with identical preoperative radiographic and physical variables (age, gender, height, weight, body mass index) were managed with combined anterior release, interbody fusion, posterior instrumentation, correction, and fusion. Group A (n=8) had morselized rib graft inserted into each intervertebral disc space. Group B (n=7) had titanium interbody cages packed with bone graft inserted at each level. The posterior instrumentation extended from T2 to L2 in both groups.

OUTCOME MEASURES

Preoperative and postoperative curve morphometry was studied on plain radiographs by two independent observers. The indices studied included Cobb angle, Ferguson's angle, Voutsinas index, sagittal vertical axis (SVA), sacral inclination (SI), and lumbar lordosis (LL). Interbody fusion was assessed at final follow-up. Each patient was reviewed at 3, 6, 12, 24, 48, and 60 months after surgery with standing radiographs.

METHODS

Both surgical groups were compared in terms of radiological parameters and complications. Wilcoxon-matched pairs test and Mann-Whitney test were used.

RESULTS

The average follow-up for Group A was 70 months and for Group B 66 months. For the whole group, the preoperative median Cobb angle for thoracic kyphosis was 86 degrees , the median Ferguson angle was 50 degrees , Voutsinas index was 28.7, SVA -3.5 centimeters, lumbar lordosis was 66 degrees , and the median sacral inclination angle was 40 degrees . The median postoperative Cobb angle was 42 degrees , Ferguson angle 28.4 degrees , Voutsinas index 13, SVA -4.0 centimeters, and the median sacral inclination angle was 34 degrees . There were significant differences between preoperative and postoperative measurements for all variables (p<.01), indicating that good correction was achieved. At 4-year follow-up, fusion criteria were satisfied in 12 of 15 cases (80%). Three patients had distal junctional kyphosis. There was no significant difference obtained in the final Cobb angle, Ferguson angle, and Voutsinas index when Group A (rib graft) was compared with Group B (titanium cage) Both Group A and B patients retained the postoperative correction achieved with respect to all the radiographic parameters studied.

CONCLUSION

We were unable to demonstrate any significant advantage for the use of anterior titanium interbody cages over the use of morselized rib graft in the surgical management of Scheuermann's kyphosis. Given the not inconsiderable cost and the need for posterior chevron osteotomies when interbody cages are used, we have now reverted to our previous practice of using morselized rib graft at each intervertebral level.

Experience with combined video-assisted thoracoscopic surgery (VATS) anterior spinal release and posterior spinal fusion in Scheuermann's kyphosis

STUDY DESIGN

Retrospective.

OBJECTIVES

To determine whether anterior endoscopic release and posterior spinal fusion could achieve stable correction in Scheuermann's kyphosis.

SUMMARY OF BACKGROUND DATA

The initial treatment of choice of Scheuermann's kyphosis is thoracic hyperextension and postural exercises and/or Milwaukee brace. Milwaukee bracing is most efficacious in the early stages when the curvature is flexible and in the skeletally immature. However, it is known that larger curves, vertebral wedging greater than 10 degrees, and skeletally mature patients will not usually respond to this treatment. Surgery is indicated in the skeletally immature with severe deformity where brace treatment has failed to prevent progression. Posterior spinal instrumentation can achieve adequate correction in the less rigid curves. However, the more rigid curves have been shown to be resistant to posterior spinal fusion alone, therefore needing anterior spinal release.

METHODS

Between 1995 and 2001, 19 patients underwent video-assisted thoracoscopic surgery and posterior spinal fusion for the treatment of Scheuermann's kyphosis. The average age was 17.4 years with closed triradiate cartilage in all. Average follow-up was 2.7 years. An average of 8.3 discs were released anteriorly; an average of 13 levels were fused posteriorly.

RESULTS

Average preoperative kyphosis was 84.8 degrees. Average postoperative kyphosis was 43.7 degrees. Average kyphosis at follow-up was 45.3 degrees. Only 1.6 degrees of correction loss was noted. No junctional kyphosis was present. Two patients developed pleural effusion; one required thoracocentesis. Two patients developed pneumothorax. One patient underwent revision surgery for inferior hook pullout. One required mechanical ventilation.

CONCLUSIONS

Combined video-assisted thoracoscopic surgery release and posterior spinal fusion for the treatment of Scheuermann's kyphosis is a viable option for the treatment of the more severe and rigid curves.

Scheuermann kyphosis: safe and effective surgical treatment using multisegmental instrumentation

STUDY DESIGN

A retrospective review was conducted on 23 consecutive patients who underwent surgical correction of Scheuermann kyphosis using modern multisegmental instrumentation.

OBJECTIVE

To evaluate Scheuermann kyphosis correction and complication rates.

SUMMARY OF BACKGROUND DATA

The surgical treatment of Scheuermann kyphosis remains a topic of debate. The literature of the 70s and 80s on the surgical management of this disorder using Harrington instrumentation demonstrated that operative correction is quite effective but associated with significant complications. This literature, however, may be less applicable to current clinical situations. The use of modern multisegmental instrumentation and increased awareness of potential complications may decrease the risks of current operative treatment.

METHODS

Hospital charts, office charts, and radiographs on 23 consecutive patients who underwent operative treatment using multisegmental instrumentation for Scheuermann kyphosis were reviewed to identify complications of surgery. Complications were classified as minor, major, or life threatening.

RESULTS

The mean follow-up was 38 months (range 10-123 months). Preoperative kyphosis ranged from 63 degrees to 104 degrees with an average of 83 degrees. Twenty of the 23 patients (87%) underwent combined anterior release/arthrodesis with posterior arthrodesis/multisegmental instrumentation. The remaining 3 patients underwent posterior arthrodesis/multisegmental instrumentation. Postoperative total kyphosis ranged from 32 degrees to 67 degrees with an average of 46 degrees. At final follow-up, the total kyphosis ranged from 37 degrees to 75 degrees with an average of 51 degrees. Overall, we had 43% minor complications, 17% major complications, and 0% life-threatening complications.

CONCLUSIONS

Surgical correction of Scheuermann kyphosis can be performed safely and effectively using modern multisegmental instrumentation.

Combined anterior–posterior fusion with laterally placed threaded interbody cages and pedicle screws for Scheuermann kyphosis

The authors report their preferred method for correcting Scheuermann disease via a combined anterior–posterior approach; their procedure is associated with a lower morbidity rate than the standard approach. Twenty-month follow-up examination demonstrated excellent maintenance of correction. The results satisfied the requirements to function without restriction in a vigorous military environment.

Analysis of the sagittal plane after surgical management for Scheuermann's disease: a view on overcorrection and the use of an anterior release

STUDY DESIGN

A historic cohort study was conducted to investigate surgical correction and sagittal alignment in 33 patients with thoracic Scheuermann's disease.

OBJECTIVE

To evaluate kyphosis correction, correction loss, sagittal balance, and the effect of an anterior release.

SUMMARY OF BACKGROUND DATA

Currently, both posterior and anteroposterior techniques seem to produce impressive corrections for Scheuermann's disease. However, few reports have been made on sagittal malalignment after surgery.

METHODS

A cohort of 33 patients who had undergone surgery for their Scheuermann's kyphosis were reviewed: Group A: posterior technique (n = 16), Group B: anteroposterior technique (n = 17). Pre- and postoperative curve morphometry (Cobb, Ferguson, Voutsinas), balance (C7 plumb line), and Oswestry score were compared.

RESULTS

The mean follow-up period was 4.5 +/- 2 years (range, 2-8.2 years). The mean preoperative kyphosis (Cobb) was 78.7 degrees +/- 8.9 degrees, and the mean postoperative kyphosis was 51.7 degrees +/- 10.3 degrees. At follow-up evaluation, the correction loss was 1,4 degrees +/- 3.9 degrees. There was no difference in curve morphometry, correction, sagittal balance, average age, and follow-up period between Groups A and B. One junctional kyphosis, in Group B, was noted. After surgery, all the patients were satisfied, and the Oswestry score showed significant improvement. No neurologic complications were observed.

CONCLUSIONS

Good follow-up results included a 100% follow-up rate, adequate corrections, little correction loss, lower Oswestry scores, and a high satisfaction rate in both groups. The anteroposterior treatment did not influence the curve morphometry more than posterior fusion only. In reducing postoperative sagittal malalignment, the authors believe that surgical management should aim at a correction within the high normal kyphosis range of 40 degrees to 50 degrees, consequently providing good results and, particularly in flexible adolescents and young adults, minimizing the necessity for an anterior release.

Scheuermann kyphosis: long-term follow-up

BACKGROUND CONTEXT

There is considerable controversy as to the optimal treatment of Scheuermann kyphosis. Proposed modalities have included exercise, bracing and surgery.

PURPOSE

The purpose of this study was to document the functional capacity and radiographic findings in adults who have been previously treated for Scheuermann kyphosis.

STUDY DESIGN

A cohort study of all patients with Scheuermann kyphosis treated in a single institution using three different treatment modalities: exercise and observation, Milwaukee bracing and surgical fusion using the Harrington Compression System.

PATIENT SAMPLE

Sixty-three patients were evaluated at a mean of 14 years after treatment (10 to 28 years).

OUTCOME MEASURES

Two different functional evaluation instruments were used. Radiographic evaluation was carried out in 38 patients (60%).

METHODS

Patient interviews were conducted using a specially designed questionnaire. Patients were then asked to undergo standing radiographs. Patients were divided into groups depending on the location of their kyphosis and the manner in which they had been treated. Standard statistical analysis was then carried out.

RESULTS

At time of follow-up evaluation there were no differences in marital status, general health, education level, work status, degree of pain and functional capacity between the various curve types, treatment modality and degree of curve. Patients treated by bracing or surgery did have improved self-image, which they attributed to their treatment. Patients with kyphotic curves exceeding 70 degrees at follow-up had an inferior functional result. At time of final follow-up there were no statistical differences in degree of kyphosis and mode of treatment.

CONCLUSIONS

By carefully selecting the appropriate treatment for patients with Scheuermann kyphosis on the basis of the patient's age, spinal deformity and the severity of back pain, it is possible to achieve a similar functional result at long-term follow-up. Despite different treatment protocols, patients with Scheuermann kyphosis tend to achieve a similar functional result at long-term follow-up.

Surgical treatment of Scheuermann's disease with segmental compression instrumentation

Twenty-one patients with Scheuermann's kyphosis had surgery for progressive kyphotic deformity of 50 degrees or greater. There were six adolescents, with a mean age of 15.6 years (range, 13-17 years) and 15 young adults, with a mean age of 25.4 years (range, 18-40 years). All patients had posterior spine arthrodesis with segmental compression instrumentation. Seven patients with rigid kyphosis had combined anterior and posterior spine arthrodesis. One patient died of superior mesenteric artery syndrome. In the group of 13 patients with posterior arthrodesis only, followup was 4.5 years. The mean preoperative thoracic kyphotic curve of 68.5 degrees improved to 40 degrees at latest review, with an average loss of correction of 5.75 degrees. Junctional kyphosis occurred in two patients with a short arthrodesis: one at the cephalad end and one at the caudal end of the fused kyphotic curve. In the second group of seven patients with combined anterior and posterior arthrodesis, followup was 6 years. The mean preoperative thoracic kyphotic curve of 86.3 degrees improved to 46.4 degrees at latest review, with an average loss of correction of 4.4 degrees. Overall, there was no postoperative neurologic deficit and no pseudarthrosis. Thus, posterior arthrodesis and segmental compression instrumentation seems to be effective for correcting and stabilizing kyphotic deformity in Scheuermann's disease. Despite a long operating time, this technique provided significant correction, avoiding the development of any secondary deformity in most patients. Combined anterior and posterior spine arthrodesis is recommended for rigid, more severe kyphotic deformities.

Transient paraparesis: a complication of the surgical management of Scheuermann's kyphosis secondary to thoracic stenosis

STUDY DESIGN

Transient paraparesis during the operative management of a 16-year-old patient with Scheuermann's kyphosis secondary to thoracic stenosis is reported.

OBJECTIVE

To describe a treatable cause for paraparesis in a patient with Scheuermann's kyphosis undergoing surgical treatment.

SUMMARY OF BACKGROUND DATA

Cord injury in the surgical treatment of Scheuermann's kyphosis is a rare event, yet it is felt to be more common in the surgical correction of kyphosis than in surgery for scoliosis. Suggested etiologies have included vascular insufficiency, hypotension, direct mechanical trauma, and neural element stretch. Concomitant thoracic spinal stenosis predisposing to neurologic injury during surgical manipulation has not been reported.

METHODS

A 16-year-old boy with progressive Scheuermann's kyphosis measuring 80 degrees from T7 to T12 underwent an anteroposterior spinal fusion with somatosensory-evoked potential monitoring and wake-up tests. During the instrumentation posteriorly, somatosensory-evoked potential monitoring became markedly abnormal. This was followed by a wake-up test that demonstrated the patient's inability to move either of his lower extremities. All instrumentation was removed. The patient had recovered neurologic function by the time he reached the recovery room. A computed tomography myelogram was performed on the third postoperative day, which demonstrated severe thoracic stenosis from T8 to T10. The patient was returned to the operating room 1 week later to undergo a posterior laminectomy from T7 to T11 and instrumented fusion from T5 to L2. Somatosensory-evoked potential monitoring was stable throughout this procedure, and the wake-up test was normal.

RESULTS

The patient's postoperative course and subsequent 2-year follow-up period were unremarkable. He progressed to clinical and radiographic union and maintained a normal lower extremity neurologic examination.

CONCLUSIONS

A treatable cause for paraparesis secondary to the surgical treatment of Scheuermann's kyphosis is presented. The author currently obtains a thoracic magnetic resonance image (MRI) before the surgical correction of any patients with Scheuermann's kyphosis.

Scheuermann's kyphosis

Scheuermann's disease is a kyphotic deformity of the spine that develops in early adolescence. This condition has been reported to occur in 0.4% to 8% of the general population, with an equal distribution between sexes. Diagnosis of Scheuermann's disease is suggested on clinical examination; however, parents of children affected often confuse it with poor posture. Radiographs are the standard imaging modality used to confirm the diagnosis of Scheuermann's disease. Classic signs include vertebral end plate irregularity, disk space narrowing, and anterior wedging of involved vertebral bodies. Other diagnostic tools such as CT scans or magnetic resonance imaging may also be of value in the evaluation of Scheuermann's disease. The mode of treatment for this condition depends upon the severity of the deformity, remaining growth, and presence or absence of symptoms. Early treatment may be limited to observation and exercises, whereas patients who have kyphosis of up to 75 degrees and how have growth remaining may benefit from bracing. Surgical correction is reserved for severe cases that are symptomatic and refractory to conservative management.

Clinical outcome after fusion of the thoracic or lumbar spine in the adult patient

This article highlights those disease processes for which fusion is used most frequently in the adult. Although the focus is on clinical outcome after fusion, the indications and natural history of the process itself are also briefly discussed to provide a comparative basis on which outcomes may be judged.

Nutritional depletion in staged spinal reconstructive surgery. The effect of total parenteral nutrition

STUDY DESIGN

A prospective randomized study evaluating nutritional depletion in spine surgery patients.

OBJECTIVE

To determine whether use of total parenteral nutrition (TPN) in patients undergoing staged spinal reconstructive procedures could affect their nutritional parameters or decrease their complication rates.

SUMMARY OF BACKGROUND DATA

Several studies have shown that nutritional depletion occurs after major spinal surgery and that patients undergoing staged spinal surgery may be at particular risk of nutritional loss and its complications.

METHODS

Forty adult patients undergoing staged spinal reconstructive surgery were randomized as to whether they received TPN postoperatively. Nutritional parameters, including skin fold measurement and albumin, pre-albumin, transferrin, and total lymphocyte counts, were obtained pre-operatively and at regular intervals.

RESULTS

Five patients did not complete the study, leaving 35 patients for analysis. There was a significant decrease in incidence of albumin and pre-albumin depletion for the patients who did not receive TPN compared with those who did receive TPN (P < 0.025, P < 0.006, respectively). Patients with depleted albumin or pre-albumin counts were more likely to develop other postoperative infectious complications such as pneumonia or urinary tract infections (P < 0.035). There were no statistically significant differences in wound complications in this small patient study. There were no complications secondary to use of the TPN.

CONCLUSIONS

For complex patients requiring staged anterior/posterior surgery, TPN appears to significantly lessen the decrease in nutritional parameters. Because depletion of nutritional parameters appears to correlate with an increased likelihood of perioperative infectious complications, use of TPN may result in a decrease of such complications in these patients.

Indications for surgery in so-called "regular" thoracic and thoracolumbar kyphosis

Idiopathic thoracic, thoracolumbar, and Scheuermann's kyphosis do not figure in the same global entity. We propose a classification for so-called "regular" kyphosis. This classification is based on the location of the most rigid curvature segment. Segmental kyphosis may be short, in which case we can distinguish between four types: high kyphosis (type I), middle kyphosis (type II), low or thoracolumbar kyphosis (type III), and segmental kyphosis, which can extend along the entire thoracic spine (type IV). The symptomatology and therapeutic indications are different for each type. We report a series of 15 patients (6 female, 9 male), aged between 18 and 33 years (average age 24 years). The mean kyphosis angle (Cobb angle) in type I patients (n = 3) was 75 degrees in type II patients (n = 3) it was 82 degrees, and in type III patients (n = 9) it was 78 degrees. The pain was greater in type III patients. All patients were operated on using a double approach. As the first step, we performed an anterior approach, disc excision, and bone graft. Ten days later, a posterior approach with CD instrumentation was carried out on ten levels. The mean follow-up is 4 years (range 9 months in 7 years). We noticed no neurological complications and one case of late sepsis. Mean angular loss of correction was 6 degrees. The correction obtained depended on the type of kyphosis. We obtained a mean postoperative Cobb angle of 63 degrees in type I curves, 55 degrees in type II, and 45 degrees in type III. The new classification allows a better understanding of regular kyphosis and helps to define clinical and therapeutic approaches. An analysis of the resulting surgical correction can also be made by comparing homogeneous groups of patients.

Spinal deformity

Spinal deformity in children has a wide range of causes. The most common entities are idiopathic scoliosis, postural roundback, and Scheuermann's kyphosis. The pediatrician, primary care physician, and orthopedic surgeon can optimally treat these disorders with close observation, attention to detail, initiation of bracing when indicated, and surgery on patients who have an appropriate indication. A careful, well-planned approach to these conditions results in the successful treatment of spinal deformities with minimal complications. The physiologic and psychological sequelae of these entities can then be minimized, preserving the overall health of the child.

Perioperative complications of anterior procedures on the spine

We reviewed the operative and hospital records of 447 patients in order to determine the rates of perioperative complications associated with an anterior procedure on the thoracic, thoracolumbar, or lumbar spine. The anterior procedures were performed to treat spinal deformity or for débridement or decompression of the spinal canal. The diagnostic groups that we studied included idiopathic scoliosis in adolescents or young adults (100 patients), scoliosis in mature adults (sixty-three patients), kyphosis (sixty-one patients), neuromuscular scoliosis (sixty patients), fracture (forty-seven patients), a revision procedure (thirty-nine patients), congenital scoliosis (thirty-six patients), tumor (nineteen patients), vertebral osteomyelitis or discitis (eight patients), and miscellaneous (fourteen patients). Complications occurred in 140 (31 per cent) of the 447 patients and were classified as major or minor. Forty-seven patients (11 per cent) had at least one major complication and 109 (24 per cent) had at least one minor complication. Two patients died, both from pulmonary complications after the operation. The most common type of major complication was pulmonary; the most common type of minor complication was genito-urinary. The adolescent or young adult patients who had idiopathic scoliosis had the lowest rate of complications, and the patients who had neuromuscular scoliosis had the highest. An age of more than sixty years at the time of the operation was associated with a higher risk of complications. The duration of the procedures involving a thoracic approach was shorter than that of those involving a thoracolumbar or lumbar approach; however, the rate of complications was not significantly different among the three approaches. Vertebrectomies took longer to perform and were associated with a greater estimated blood loss than discectomies; however, there was no significant difference in the rate of complications between the two types of procedures. The patients who had a fracture or a tumor lost more blood than those from the other diagnostic groups. Blood loss increased as the duration of the operation increased for all procedures. Combined anterior and posterior procedures performed during the same anesthesia session were associated with a higher rate of major complications than were procedures that were staged. A logistical regression analysis showed that the variables that increased the risk of a major complication were an estimated blood loss of more than 520 milliliters and an anterior and posterior procedure performed sequentially under the same anesthesia session. This analysis also demonstrated that the diagnosis of idiopathic scoliosis in adolescents or young adults was associated with a reduced risk of major complications. Compared with other major operations, an anterior procedure on the thoracic, thoracolumbar, or lumbar spine performed for the indications mentioned in this study is relatively safe.

The natural history and long-term follow-up of Scheuermann kyphosis

Sixty-seven patients who had a diagnosis of Scheuermann kyphosis and a mean angle of kyphosis of 71 degrees were evaluated after an average follow-up of thirty-two years (range, ten to forty-eight years) after the diagnosis. All sixty-seven patients completed a questionnaire; fifty-four had a physical examination and radiographs; fifty-two, pulmonary function testing; and forty-five, strength-testing of the trunk muscles. The results were compared with those in a control group of thirty-four subjects who were matched for age and sex. The patients who had Scheuermann kyphosis had more intense back pain, jobs that tended to have lower requirements for activity, less range of motion of extension of the trunk and less-strong extension of the trunk, and different localization of the pain. No significant differences between the patients and the control subjects were demonstrated for level of education, number of days absent from work because of low-back pain, extent that the pain interfered with activities of daily living, presence of numbness in the lower extremities, self-consciousness, self-esteem, social limitations, use of medication for back pain, or level of recreational activities. Also, the patients reported little preoccupation with their physical appearance. Normal or above-normal averages for pulmonary function were found in patients in whom the kyphosis was less than 100 degrees. Patients in whom the kyphosis was more than 100 degrees and the apex of the curve was in the first to eighth thoracic segments had restrictive lung disease. Five patients had an unexplained, mildly abnormal neurological examination. Mild scoliosis was common; spondylolisthesis was not observed.

Juvenile and idiopathic kyphosis. Long-term follow-up of 20 cases

Twelve patients with juvenile kyphosis and eight patients with idiopathic kyphosis were reviewed at an average follow-up of 19 years. The average age of the patients at follow-up was 33 years (range 26-45 years). All the patients but one, who had a posterior fusion of the dorsal spine, had been treated with a plaster cast jacket followed by a plastic brace. At the end of treatment there had been an improvement of about 30% on the original curves in both juvenile and idiopathic kyphosis. At follow-up, however, all the patients had lost the correction obtained and the curves had become worse than originally, those in idiopathic kyphosis more so than those in juvenile kyphosis. Despite the increase in their angular deformity, all the patients managed fairly well and only two complained of distressing back pain.

Sexual behavior: its genetic control during development and adulthood in Drosophila melanogaster

Courtship behavior in Drosophila melanogaster males is an innate behavior pattern. Whether or not a fly will display male courtship behavior is governed by the action of a set of regulatory genes that control all aspects of somatic sexual differentiation. The wild-type function of one of these regulatory genes, transformer-2 (tra-2), is necessary for female sexual differentiation; in the absence of tra-2+ function XX individuals differentiate as males. A temperature-sensitive tra-2 allele has been used to investigate, by means of temperature shifts, when and how male courtship behavior is specified during development. The removal of tra-2ts function in the adult (by a shift of the tra-2ts mutant flies to the restrictive temperature) can lead to the appearance of male courtship behavior in flies that otherwise would not display these behaviors. These experiments suggest that the regulatory hierarchy controlling sexual differentiation is functioning in the adult central nervous system. More importantly, these results suggest that the adult central nervous system has some functional plasticity with respect to the innate behavioral pattern of male courtship and is maintained in a particular state of differentiation by the active control of gene expression in the adult.

Two hereditary spinal diseases producing kyphosis during adolescence

Familial accumulation of spinal osteochondrosis (Scheuermann's disease) and hereditary juvenile anterior fusion of the vertebral bodies in the thoraco-lumbal area are reported for the first time in the same family. Radiological examination of the spine in 2 planes of 73 persons formed the basis for the study. Nine cases of spinal osteochondrosis and 5 cases of hereditary juvenile anterior fusion were found. Proliferation and increased height of the anterior surface of the body of the vertebrae and pronounced reduction in the anterior aspect of the intervertebral spaces were characteristic during the early stages of the latter condition, similarly fewer back symptoms and a better prognosis were observed in these patients than was the case of patients with Scheuermann's disease.