Surgical treatment of Scheuermann's kyphosis using a combined antero-posterior strategy and pedicle screw constructs: efficacy, radiographic and clinical outcomes in 111 cases

Changes in sagittal balance and pre-existing junctional angle influence development of proximal junctional kyphosis in growth guidance systems for early-onset scoliosis

PURPOSE

Proximal junctional kyphosis (PJK) has been reported to occur at a rate of about 30% in traditional growing rods (GR) and magnetically controlled growing rods (MCGR). Growth guidance systems (GGS) have non-rigid, gliding fixation along rods, which may mitigate PJK. There have been no studies done in shilla around PJK, hence this study aimed to assess the occurrence, risk factors, and timeline of PJK.

METHODS

A prospective, multicenter database was queried for EOS patients who underwent surgery utilizing GGS.

INCLUSION CRITERIA

< 10 years at index surgery and > 2 year follow-up.

RESULTS

Sixty-five patients (thirty-six female) met inclusion criteria. Mean age at index surgery was 6.2 y/o (2-9); mean follow-up was 66 m. Most common etiologies were syndromic (n = 23). Mean thoracic kyphosis at pre-op was 41.8°, post-op was 35.5°, and final was 42.2°. Mean PJA at pre-op was 6.15°, post-op 1 was 4.2°, and final was 15.6°. Incidence of PJK at post-op was 35% and final was 43%. Pre-op sagittal balance and change in sagittal balance from pre-op to post-op were associated with post-op PJK (p = 0.05, 0.02). Change in spinal height from pre-op to post-op was associated with PJK at final (p = 0.04). Interestingly, increased PJA at pre-op was significantly associated with decreased PJK at post-op and final (p = 0.01, 0.03).

CONCLUSION

PJK was identified in 43% of patients post-operatively after GGS for EOS. Pre-op PJA was negatively correlated with an increased incidence of PJK. Changes in sagittal balance, in either direction, was the strongest predictor for development of PJK post-operatively.

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.

Evaluation of the accuracy of new modalities in the assessment and classification of lumbar lordosis: A comparison to Cobb's angle measurement

Background

Because of the association of lumbar lordosis with some clinical conditions such as low back pain, the chiropractic field has emphasized the significance of evaluating the lumbar lordotic status, by measuring Cobb's angle, regarded as the radiological gold standard, for the assessment of lumbar lordosis, on lateral radiographs. However, research has shown that this technique has some considerable drawbacks, mostly in terms of low accuracy and high variability between clinicians when compared with other radiological modalities. The main objective was to compare the diagnostic accuracy of newly established radiological measurements with one of Cobb's angle methods, for the characterization of lumbar lordosis status in a sample of Lebanese patients aged 15 and above.

Material and methods

This retrospective single-center study consisted of measuring Cobb's L1-S1 and Cobb's L1-L5 angles, along with the novel established measurements which are the derivative and the normalized surface area, on 134 lateral radiographs of the lumbar spine of Lebanese patients aged fifteen years old and above, gotten from the Radiology department at Zahra'a's Hospital in Beirut, performed by two observers using MATLAB. Inter-rater agreement was assessed by calculating the Intra-class correlation coefficients. Spearman correlation was analyzed between both Cobb's angle methods and with the derivative and normalized area respectively. 54 patients of the sample were diagnosed by two radiologists, according to their LL status. ROC curve analysis was performed to compare the diagnostic accuracy of the four techniques used. Data were analyzed with IBM SPSS Statistics 23.0 (NY, USA); P < 0.05 was considered statistically significant.

Results

According to the ROC curve analysis the new methods, which are the derivative and the normalized surface area, displayed lower diagnostic accuracy (AUCderivative = 0.818 and 0.677, AUCsurface area = 0.796 and 0.828) than Cobb's L1-L5 (AUCL1-L5 = 0.924 and 0.929 values) and L1-S1 (AUCL1-S1 = 0.971 and 0.955) angles, in the characterization of hypo and hyperlordotic patients, respectively, in our Lebanese sample consisting of patients aged 15 and above, because of their lower area under the curve's values compared to the traditional Cobb's techniques. The Cobb's L1-S1 has shown to have the highest diagnostic accuracy among the four methods to characterize normal patients from hypo and hyperlordotic ones, by referring to its highest area under the curve's values. However, the sensitivity of Cobb's L1-L5 angle in characterizing hyperlordotic patients was similar to the one of the normalized surface area with a value of 100%.Conclusion: among the four modalities, the new methods didn't show a better diagnostic accuracy compared to the traditional modalities. Cobb's L1-S1 displayed the highest diagnostic accuracy despite its drawbacks. Further prospective studies are needed to validate the cut-offs obtained for Cobb's L1-S1 angle in our sample.

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.

Paediatric Spinal Deformity Surgery: Complications and Their Management

Surgical correction of paediatric spinal deformity is associated with risks, adverse events, and complications that must be preoperatively discussed with patients and their families to inform treatment decisions, expectations, and long-term outcomes. The incidence of complications varies in relation to the underlying aetiology of spinal deformity and surgical procedure. Intraoperative complications include bleeding, neurological injury, and those related to positioning. Postoperative complications include persistent pain, surgical site infection, venous thromboembolism, pulmonary complications, superior mesenteric artery syndrome, and also pseudarthrosis and implant failure, proximal junctional kyphosis, crankshaft phenomenon, and adding-on deformity, which may necessitate revision surgery. Interventions included in enhanced recovery after surgery protocols may reduce the incidence of complications. Complications must be diagnosed, investigated and managed expeditiously to prevent further deterioration and to ensure optimal outcomes. This review summarises the complications associated with paediatric spinal deformity surgery and their management.

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.

Surgical Procedures Used for Correction of Scheuermann's Kyphosis: A Meta-Analysis

Objectives

Scheuermann's kyphosis can cause severe back pain and cosmetic disorders to patients. Previous studies on surgical procedure selection for correction of Scheuermann's kyphosis have drawn controversial conclusions. Here, a meta-analysis was performed to figure out a better way between anterior-posterior (AP) combined procedures and posterior-only (PO) procedures.

Methods

We searched PubMed database and Ovid database, as well as Cochrane Library (between January 2009 and December 2020, around recent ten years), for studies reporting Scheuermann's kyphosis correction in an anterior way or a posterior way. Random effects meta-analysis regarding correction degrees and incidence of proximal junctional kyphosis (PJK) was performed.

Results

Finally, 13 unique studies including 586 patients (AP: 300; PO: 286) were identified and included for this meta-analysis. Overall, 6 AP cohorts and 10 PO cohorts were pooled regarding the correction degrees of kyphosis in the analysis, respectively. Pooled correction degrees in AP cohorts were 33.31 (95% CI: 27.48–39.15; I² = 86%, P < 0.001) and in PO cohorts were 31.16 (95% CI: 26.97–35.35; I² = 81.1%, P < 0.001). Comparison of correction between AP and PO cohorts did not indicate any significant difference. Likewise, postoperative PJK incidence showed no difference. Back pain can be caused by both AP and PO procedures, but which causes less pain remains to be conclusive. The PO approach showed less blood loss and shorter surgical duration as compared to the AP approach.

Conclusions

In summary, this meta-analysis shows similar treatment effects between AP and PO procedures in correcting Scheuermann's kyphosis, suggesting the advantage of PO procedures due to less blood loss and surgical duration. However, the postoperative complications PJK and distal junctional kyphosis (DJK) cannot be well concluded due to the limitation of existing data.

Contribution of postoperative vertebral remodeling to reversal of vertebral wedging and prevention of correction loss in patients with adolescent Scheuermann's kyphosis

OBJECTIVE

This study aimed to investigate reversal of vertebral wedging and to evaluate the contribution of vertebral remodeling to correction maintenance in patients with adolescent Scheuermann's kyphosis (SK) after posterior-only instrumented correction.

METHODS

A retrospective cohort study of patients with SK was performed. In total, 45 SK patients aged 10-20 years at surgery were included. All patients received at least 24 months of follow-up and had Risser sign greater than grade 4 at latest follow-up. Patients with Risser grade 3 or less at surgery were assigned to the low-Risser group, whereas those with Risser grade 4 or 5 were assigned to the high-Risser group. Radiographic data and patient-reported outcomes were collected preoperatively, immediately postoperatively, and at latest follow-up and compared between the two groups.

RESULTS

Remarkable postoperative correction of global kyphosis was observed, with similar correction rates between the two groups (p = 0.380). However, correction loss was slightly but significantly less in the low-Risser group during follow-up (p < 0.001). The ratio between anterior vertebral body height (AVBH) and posterior vertebral body height (PVBH) of deformed vertebrae notably increased in SK patients from postoperation to latest follow-up (p < 0.05). Loss of correction of global kyphosis was significantly and negatively correlated with increased AVBH/PVBH ratio. Compared with the high-Risser group, the low-Risser group had significantly greater increase in AVBH/PVBH ratio during follow-up (p < 0.05). The two groups had similar preoperative and postoperative Scoliosis Research Society-22 questionnaire scores for all domains.

CONCLUSIONS

Obvious reversal in wedge deformation of vertebrae was observed in adolescent SK patients. Patients with substantial growth potential had greater vertebral remodeling and less correction loss. Structural remodeling of vertebral bodies has a positive effect and protects against correction loss. These results could be help guide treatment decision-making.

Revision risk after pediatric spinal deformity surgery: a nationwide study with 2-year follow-up

BACKGROUND CONTEXT

Revision risk after pediatric spine surgery is not well established and varies between deformity etiologies.

PURPOSE

To report the 2-year revision risk following surgery for primary pediatric spinal deformity in a nationwide cohort and to evaluate potential risk factors and reasons for revision surgery.

DESIGN

Retrospective nationwide cohort study.

PATIENT SAMPLE

A national registry study of all pediatric spinal deformity patients undergoing surgery during 2006-2015 (n=1310).

OUTCOME MEASURES

Two-year revision risk.

METHODS

All patients ≤21 years of age undergoing spinal deformity surgery in Denmark during 2006-2015 were identified by procedure and diagnosis codes in the Danish National Patient Registry (DNPR). Data on revision surgery were retrieved from the DNPR. Patients were categorized in six groups according to etiology. Medical records were reviewed for reason for revision in all patients. Potential risk factors for revision were assessed with multiple logistic regression analyses and included age, etiology, sex, Charlson comorbidity index (CCI), and growth-preserving treatment.

RESULTS

Patients were categorized according to etiology: idiopathic deformity (53%), neuromuscular deformity (23%), congenital/structural deformity (9%), spondylolisthesis (7%), Scheuermann's kyphosis (5%), and syndromic deformity (3%). Of 1,310 included patients, 9.2% underwent revision surgery within 2 years and 1.5% was revised more than once. Median time to revision was 203 (interquartile range 35-485) days. The multivariable logistic regression found significantly higher odds ratio (OR) for revision in patients with growth-preserving treatment (OR=5.1, 95% confidence interval [CI] 2.6-10.1), congenital deformity (OR=2.7, 95% CI 1.3-5.3), spondylolisthesis (OR=3.5, 95% CI 1.9-6.7), Scheuermann kyphosis (OR=3.9, 95% CI 1.9-8.3), and CCI score ≥3 (OR=2.5 95% CI 1.1-5.6). The most common reason for revision was implant failure (32.5%) followed by residual deformity and/or curve progression (15.8%).

CONCLUSIONS

In this nationwide study, the 2-year revision risk after primary pediatric spinal deformity surgery is 9.2%. Risk factors for revision are etiology of congenital deformity, spondylolisthesis, Scheuermann kyphosis as well as patients with growth-preserving treatment and higher CCI. The most common reason for revision is implant failure.

The surgical treatment of severe Scheuermann's kyphosis

AIMS

To report the surgical outcome of patients with severe Scheuermann's kyphosis treated using a consistent technique and perioperative management.

METHODS

We reviewed 88 consecutive patients with a severe Scheuermann's kyphosis who had undergone posterior spinal fusion with closing wedge osteotomies and hybrid instrumentation. There were 55 males and 33 females with a mean age of 15.9 years (12.0 to 24.7) at the time of surgery. We recorded their demographics, spinopelvic parameters, surgical correction, and perioperative data, and assessed the impact of surgical complications on outcome using the Scoliosis Research Society (SRS)-22 questionnaire.

RESULTS

The mean follow-up was 8.4 years (2 to 14.9). There were 85 patients (96.6%) with a thoracic deformity. Posterior spinal fusion with closing-wedge osteotomies and hybrid instrumentation was used in 86 patients; two patients underwent combined anterior and posterior spinal fusion. The mean kyphosis was corrected from 94.5° to 47.5° (p < 0.001). Coronal and sagittal balance returned to normal. The rate of complications was 12.5%: there were no neurological deficits, implant failure, or revision surgery. SRS-22 scores improved from a mean 3.6 (1.3 to 4.1) to 4.6 (4.2 to 5.0) at two years (p < 0.001) with a high rate of patient satisfaction. Non-smokers and patients with lower preoperative SRS-22 scores showed greater improvement in their quality of life. Sagittal pelvic balance did not change after correction of the kyphosis and correlated with lumbar lordosis but not with thoracic or thoracolumbar kyphosis.

CONCLUSION

Posterior spinal fusion using hybrid instrumentation, closing-wedge osteotomies, and iliac bone grafting achieves satisfactory correction of a severe kyphosis resulting in improvements in physical and mental health and a high degree of patient-reported satisfaction. Cite this article: Bone Joint J 2021;103-B(1):148-156.

Maria Adelaide brace in the management of Scheuermann's Kyphosis

PURPOSE

This prospective observational study aims to assess the MA brace effectiveness in hyperkyphosis correction, focusing also on patients' compliance of bracing and its psychological impact.

METHODS

Patients referring to our spine outpatient department with Scheuermann's kyphosis (SK) from January 2011 to January 2017 were prospectively recruited. Patients were divided into two groups, according to their global thoracic kyphosis (TK): Group-A TK_T0 < 60°, Group-B TK_T0 ≥ 60°. The MA brace was prescribed according to SRS criteria. Full spine X-rays were analyzed at conventional times: at the beginning of treatment (T0), at 6-months follow-up (T1, in-brace X-rays), at the end of treatment (T2) and at 2-year minimum follow-up from bracing removal (T3). At T₀, T₂ and T₃ all the patients were assessed using the Italian Version of the SRS-22 Patient Questionnaire (I-SRS22). Variability between and within-groups was assessed; a p value < 0.05 was considered significant.

RESULTS

192 adolescents (87 girls and 105 boys, mean age 13.1) were recruited. The mean global TK at recruitment was 61.9° ± 11.3°, the mean follow-up time was 57.4 months. A good patients' reported compliance was observed: 84.9% of patients used the brace as scheduled. A mean in-brace correction (in-brace TK_%) of 37.4% was observed and a mean final correction (TK_%T3) of 31.6%. At final follow-up (T3), curve reduction (ΔTK ≤  - 5°) was observed in 60.4% of patients and curve stabilization (- 5° < ΔTK < 5) in 29.7% of patients. At baseline, worse SRS22-mental health (p = 0.023) and self-image mean scores (p = 0.001) were observed in Group-B, compared with Group-A. At the end of treatment (T2), an improvement of all items was observed, wit significantly better improvement of self-image domain in Group-B.

CONCLUSION

The MA brace has shown to be effective in the management of SK; good patients' reported compliance and a positive effect on the patients' mental status were recorded.

Under-contouring of rods: a potential risk factor for proximal junctional kyphosis after posterior correction of Scheuermann kyphosis

OBJECTIVE

Scheuermann kyphosis (SK) could require surgical treatment in certain situations. A posterior reduction is the most widespread treatment so far, although the development of proximal junctional kyphosis (PJK) is one of the possible complications of this procedure. The contour of the proximal part of the rod could influence the occurrence of PJK in SK patients. The objective of this study was to analyze the impact of the proximal rod contour on the occurrence of a PJK complication in SK patients.

METHODS

This retrospective monocentric study was performed in the Nanjing Spine Surgery Department. All eligible patients had undergone posterior correction surgery with pedicle screws only between 2002 and 2017 and had at least 24 months of follow-up. The presence of PJK was quantified on radiographs using the proximal junctional angle (PJA > 10° at the last follow-up). The authors propose a new radiological parameter to measure the angulation of the proximal part of the instrumentation: the proximal contouring rod angle (PCRA) is the angle between the upper endplate of the upper instrumented vertebra (UIV) and the lower endplate of the second vertebra caudal to the UIV. The patients were analyzed according to the presence or absence of PJK. A t-test, receiver operating characteristic (ROC) curve analysis, and logistic regression analysis were performed for statistical analysis.

RESULTS

Sixty-two patients treated for SK were included in this study. The mean age was 18.6 ± 8.5 years, and the mean follow-up was 42.5 ± 16.4 months. The mean correction rate of global kyphosis was 46.4% ± 13.7%. At the last follow-up, 17 patients (27.4%) presented with PJK. No significant difference was found between the PJK and non-PJK groups in terms of age and other preoperative variables. A significant difference in the postoperative PCRA was found between the PJK and non-PJK groups (8.2° ± 4.9° vs 15.7° ± 6.6°, respectively; p = 0.001). A postoperative PCRA less than 10.1° predicted a significantly higher risk for PJK (p = 0.002, OR 2.431, 95% CI 1.781-4.133).

CONCLUSIONS

Under-contouring of the proximal part of the rods (lower than 10°) is a risk factor for PJK after posterior correction of SK.

Treatment approaches for Scheuermann kyphosis: a systematic review of historic and current management

OBJECTIVE

Scheuermann kyphosis (SK) is an idiopathic kyphosis characterized by anterior wedging of ≥ 5° at 3 contiguous vertebrae managed with either nonoperative or operative treatment. Nonoperative treatment typically employs bracing, while operative treatment is performed with either a combined anterior-posterior fusion or posterior-only approach. Current evidence for these approaches has largely been derived from retrospective case series or focused reviews. Consequently, no consensus exists regarding optimal management strategies for patients afflicted with this condition. In this study, the authors systematically review the literature on SK with respect to indications for treatment, complications of treatment, differences in correction and loss of correction, and changes in treatment over time.

METHODS

Using PubMed, Embase, CINAHL, Web of Science, and the Cochrane Library, all full-text publications on the operative and nonoperative treatment for SK in the peer-reviewed English-language literature between 1950 and 2017 were screened. Inclusion criteria involved fully published, peer-reviewed, retrospective or prospective studies of the primary medical literature. Studies were excluded if they did not provide clinical outcomes and statistics specific to SK, described fewer than 2 patients, or discussed results in nonhuman models. Variables extracted included treatment indications and methodology, maximum pretreatment kyphosis, immediate posttreatment kyphosis, kyphosis at last follow-up, year of treatment, and complications of treatment.

RESULTS

Of 659 unique studies, 45 met our inclusion criteria, covering 1829 unique patients. Indications for intervention were pain, deformity, failure of nonoperative treatment, and neural impairment. Among operatively treated patients, the most common complications were hardware failure and proximal or distal junctional kyphosis. Combined anterior-posterior procedures were additionally associated with neural, pulmonary, and cardiovascular complications. Posterior-only approaches offered superior correction compared to combined anterior-posterior fusion; both groups provided greater correction than bracing. Loss of correction was similar across operative approaches, and all were superior to bracing. Cross-sectional analysis suggested that surgeons have shifted from anterior-posterior to posterior-only approaches over the past two decades.

CONCLUSIONS

The data indicate that for patients with SK, surgery affords superior correction and maintenance of correction relative to bracing. Posterior-only fusion may provide greater correction and similar loss of correction compared to anterior-posterior approaches along with a smaller complication profile. This posterior-only approach has concomitantly gained popularity over the combined anterior-posterior approach in recent years.

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.

Quality of Life Improvement Following Surgery in Adolescent Spinal Deformity Patients: A Comparison Between Scheuermann Kyphosis and Adolescent Idiopathic Scoliosis

STUDY DESIGN

Preoperative and two-year follow-up health-related quality of life (HRQOL) data were prospectively collected in 82 Scheuermann kyphosis (SK) and 995 adolescent idiopathic scoliosis (AIS) patients using the Scoliosis Research Society-22 patient questionnaire (SRS-22) outcomes instrument in a multicenter study. Visual analog scale (VAS) scores were also collected for the SK population.

OBJECTIVES

This study assessed changes in HRQOL prospectively and compared them to those occurring in AIS.

SUMMARY OF BACKGROUND DATA

There has been limited evaluation of patient-reported HRQOL changes with operative management of SK.

METHODS

Median SRS values for the SK and AIS cohorts were compared using a repeated measure of analysis of variance with age as a covariate and using a Mann-Whitney U nonparametric comparison.

RESULTS

Kyphosis was corrected from 73.9° to 45.8° (p < .001); the major curve in AIS was corrected from 55.5 to 20.2 (p < .001). Preoperative and magnitude of radiographic correction, kyphosis apex and body mass index in SK were not correlated with baseline or change in HRQOL. SK SRS scores improved after surgery in all domains with the greatest change (2.8-4.4) in self-image (p < .001). Changes in SRS Pain, Activity, and Self-Image domains met the minimal clinically important difference. Baseline SK and AIS scores differed significantly in the Self-Image, Mental Health and Total Score domains, with SK having worse scores (p < .001). At two years postoperatively, the greatest improvements were made in Self-Image, along with Mental Health and Total Score, and the SK group achieved greater gains (p < .001). At two years postoperatively, the SK scores improved to reach equivalent values to the AIS scores. VAS scores improved from 3.69 to 1.51, and these changes were correlated with change in the Pain, Mental Health, and Total Score SRS domains (p < .001).

CONCLUSIONS

Surgery for SK in the adolescent population results in significant improvements in HRQOL, which outpace those of the AIS population.

LEVEL OF EVIDENCE

Level II.

Trends in Treatment of Scheuermann Kyphosis: A Study of 1,070 Cases From 2003 to 2012

STUDY DESIGN

Retrospective review of KID Inpatient Database (KID) from 2003, 2006, 2009, and 2012.

OBJECTIVES

The aim of this study was to evaluate the impact of advances in spinal surgery on patient outcomes in the treatment of Scheuermann kyphosis (SK).

SUMMARY OF BACKGROUND DATA

SK is one of the most common causes of back pain in adolescents. Trends in diagnoses and surgical treatment and approach to SK have not been well described.

METHODS

SK patients aged 0-20 years in KID were identified by ICD-9 code 732.0. KID-supplied year- and hospital-trend weights were used to establish prevalence. Patient demographics, surgical details, and outcomes were analyzed with analysis of variance.

RESULTS

A total of 1,070 SK patients were identified (33.2% female), with increasing incidence of SK diagnosed from 2003 to 2012 (3.6-7.5 per 100,000, p < .001). The average age of operative patients was 16.1±2.0 years and did not change (16.27-16.06 years, p = .905). The surgical rate has not changed over time (72.8%-72.8%, p = .909). Overall, 96.3% of operative patients underwent fusion, with 82.2% of cases spanning ≥4 levels; in addition, 8.6% underwent an anterior-only surgery, 74.6% posterior-only, and 13.6% combined approach. From 2003 to 2012, rates of posterior-only surgeries increased (62.4%-84.4%, p < .001) whereas the rate of combined-approach surgeries decreased (37.6%-8.8%, p < .001). Overall complication rates for SK surgeries have decreased (2003: 20.9%; 2012: 11.9%, p = .029). Concurrently, the rate of ≥4-level fusions has increased (43.5%-89.6%, p < .001), as well as the use of Smith-Peterson (7.8%-23.6%, p < .001) and three-column osteotomies (0.0%-2.7%, p = .011). In subanalysis comparing posterior to combined approaches, complication rates were significantly different (posterior: 9.88%, combined: 19.46%, p = .005). Patients undergoing a combined approach have a longer length of stay (LOS) than patients undergoing a posterior-only approach (7.8 vs. 5.6 days, p < .001).

CONCLUSIONS

Despite unchanged demographics and operative rates in SK, there has been a shift from combined to isolated posterior approaches, with a concurrent increase in levels treated. A combined approach was associated with increased complication rates, LOS, and total charges compared to isolated approaches. Awareness of these inherent differences is important for surgical decision making and patient education.

LEVELS OF EVIDENCE

Level III.

Reciprocal Changes in Sagittal Alignment With Operative Treatment of Adolescent Scheuermann Kyphosis-Prospective Evaluation of 96 Patients

INTRODUCTION

Sagittal alignment abnormalities in Scheuermann kyphosis (SK) strongly correlate with quality of life measures. The changes in spinopelvic parameters after posterior spinal fusion have not been adequately studied. This study is to evaluate the reciprocal changes in spinopelvic parameters following surgical correction for SK.

METHODS

Ninety-six operative SK patients (65% male; age 16 years) with minimum 2-year follow-up were identified in the prospective multicenter study. Changes in spinopelvic parameters and the incidence of proximal (PJK) and distal (DJK) junctional kyphosis were assessed as were changes in Scoliosis Research Society-22 (SRS-22) questionnaire scores.

RESULTS

Maximum kyphosis improved from 74.4° to 46.1° (p < .0001), and lumbar lordosis was reduced by 10° (-63.3° to -53.3°; p < .0001) at 2-year postoperation. Pelvic tilt, sacral slope, and sagittal vertical axis remained unchanged. PJK and DJK incidence were 24.2% and 0%, respectively. In patients with PI <45°, patients who developed PJK had greater postoperative T2-T12 (54.8° vs. 44.2°, p = .0019), and postoperative maximum kyphosis (56.4° vs. 44.6°, p = .0005) than those without PJK. In patients with PI ≥45°, patients with PJK had less postoperative T5-T12 than those without (23.6° vs. 32.9°, p = .019). Thoracic and lumbar apices migrated closer to the gravity line after surgery (-10.06 to -4.87 mm, p < .0001, and 2.28 to 2.10 mm, p = .001, respectively). Apex location was normalized to between T5-T8 in 68.5% of patients with a preoperative apex caudal to T8, whereas 90% of patients with a preoperative apex between T5 and T8 remained unchanged. Changes in thoracic apex location and lumbar apex translation were associated with improvements in the SRS function domain.

CONCLUSION

PJK occurred in 1 in 4 patients, a lower incidence than previously reported perhaps because of improved techniques and planning. Both thoracic and lumbar apices migrated closer to the gravity line, and preoperative apices caudal to T8 normalized in more than two-thirds of patients, resulting in improved postoperative function. Individualizing kyphosis correction to prevent kyphosis and PI mismatch may be protective against PJK.

Severe rigid Scheuermann kyphosis in adult patients; correction with posterior-only approach

PURPOSE

Scheuermann kyphosis is the most common structural kyphosis among adolescence and young people. Surgical treatment may be performed through combined anterior and posterior or posterior-only approaches; to our knowledge, the efficacy of posterior-only approach as less invasive procedure is not well studied in case of severe rigid Scheuermann kyphosis.

MATERIALS AND METHODS

Eighteen patients with severe rigid Scheuermann kyphosis operated through only posterior approach from 2013 to 2016 were evaluated. All information regarding demographic data, curve size before and after the surgery, surgical time, amount of blood loss, correction loss during follow-up and also complications was collected.

RESULT

There were six females and 12 males. Mean age of the patients was 22.4 years (range 17-38). Mean kyphosis angle before surgery was 87.2° (range 85-105), and that reduced to 47.4° (range 45-55) after the surgery. Mean curve size in hyperextension view was 73.8°. Mean postoperative Cobb angle was 50-55 percent of preoperative curves. Mean hospital admission duration was 3.5 days after the index surgery (range 3-5 days). Mean blood loss during the surgery was 250 ml. Mean surgical duration time was 150 min. Mean follow-up period was 9 months (range 8-48 months). No complication was found among the patients.

CONCLUSION

Posterior-only approach using advanced osteotomy techniques and posterior release is a safe and reliable approach for treatment of patients suffering from severe rigid Scheuermann kyphosis and provides acceptable deformity correction.

Adding Satellite Rods to Standard Two-rod Construct With the Use of Duet Screws: An Effective Technique to Improve Surgical Outcomes and Preventing Proximal Junctional Kyphosis in Posterior-Only Correction of Scheuermann Kyphosis

STUDY DESIGN

A retrospective matched-cohort comparative study.

OBJECTIVE

The aim of this study was to compare the surgical results after the use of duet screw based satellite rods and bilateral satellite rods (S-RC) versus a standard two-rod construct (2-RC) across osteotomy sites in a matched cohort with Scheuermann kyphosis (SK).

SUMMARY OF BACKGROUND DATA

Multiple Ponte osteotomies are frequently employed to correct SK via a posterior-only approach, with a 2-RC across the osteotomy sites. Whereas, correction rate and junction problems remain as the major concerns.

METHODS

This study reviewed a consecutive series of patients with SK who had undergone posterior-only correction with multilevel Ponte osteotomy between 2009 and 2014 and had been followed over 24 months. Twenty-two patients receiving placement with an S-RC with the use of duet screws were identified and closely matched with 22 patients with a 2-RC in terms of age, apex, and magnitude of kyphosis. Comparisons were made with regards to deformity magnitude, correction results, complications, and clinical outcomes between the two groups.

RESULTS

No significant difference was found between groups in preoperative patient's factors (age, gender, apex, magnitude of kyphosis, and SRS-22 scores) and surgical factors (blood loss, operation time, osteotomy levels, and fused levels). Compared with the 2-RC group, the S-RC group had higher correction rate (55.4% ± 7.5% vs. 46.2% ± 5.1%, P < 0.001), less correction loss (1.0 ± 0.8° vs. 2.4 ± 1.4°, P < 0.001) during the follow-up, and higher improvement of back pain as well (P < 0.05). None were detected with pseudarthrosis or implant failure in either group, but proximal junctional kyphosis was less frequently seen in S-RC group (1 of 22) than 2-RC group (7 of 22) (P < 0.05).

CONCLUSION

As a safe method, use of S-RC is effective in providing increased kyphotic correction across multiple Ponte osteotomy levels, and improving patient-reported outcomes of management satisfaction and back pain. The biomechanical benefits of stress dispersion, coupled with increased stability and weight bearing ability, make it a powerful technique preventing correction loss and proximal junctional kyphosis.

LEVEL OF EVIDENCE

3.

Pseudarthrosis in adult and pediatric spinal deformity surgery: a systematic review of the literature and meta-analysis of incidence, characteristics, and risk factors

We conducted a systematic review with meta-analysis and qualitative synthesis. This study aims to characterize pseudarthrosis after long-segment fusion in spinal deformity by identifying incidence rates by etiology, risk factors for its development, and common features. Pseudarthrosis can be a painful and debilitating complication of spinal fusion that may require reoperation. It is poorly characterized in the setting of spinal deformity. The MEDLINE, EMBASE, and Cochrane databases were searched for clinical research including spinal deformity patients treated with long-segment fusions reporting pseudarthrosis as a complication. Meta-analysis was performed on etiologic subsets of the studies to calculate incidence rates for pseudarthrosis. Qualitative synthesis was performed to identify characteristics of and risk factors for pseudarthrosis. The review found 162 articles reporting outcomes for 16,938 patients which met inclusion criteria. In general, the included studies were of medium to low quality according to recommended reporting standards and study design. Meta-analysis calculated an incidence of 1.4% (95% CI 0.9-1.8%) for pseudarthrosis in adolescent idiopathic scoliosis, 2.2% (95% CI 1.3-3.2%) in neuromuscular scoliosis, and 6.3% (95% CI 4.3-8.2%) in adult spinal deformity. Risk factors for pseudarthrosis include age over 55, construct length greater than 12 segments, smoking, thoracolumbar kyphosis greater than 20°, and fusion to the sacrum. Choice of graft material, pre-operative coronal alignment, post-operative analgesics, and sex have no significant impact on fusion rates. Older patients with greater deformity requiring more extensive instrumentation are at higher risk for pseudarthrosis. Overall incidence of pseudarthrosis requiring reoperation is low in adult populations and very low in adolescent populations.

Surgical Orthopedics in a Spondylometaphyseal Dysplastic Patient

BACKGROUND

Spondylometaphyseal dysplasia (SMD) is a rare disease characterized by vertebral and metaphyseal abnormalities. The treatment of SMD spinal deformities remains a challenge for spinal surgeons. The purpose of this study is to demonstrate the feasibility and effectiveness of vertebral column resection of SMD by thoracolumbar kyphosis and scoliosis.

CASE DESCRIPTION

A 23-year-old man with SMD was referred to us with multivertebral anomalies and scoliosis, and a rigid curved thoracolumbar kyphosis in T11-12. The patient had fixed thoracolumbar kyphosis and scoliosis with neurologic symptoms. The morphology of vertebra was measured and calculated based on radiologic data. A 3-dimensional printing was made to help the spinal orthopedics. The anterior fusion was made with cages reconstruction and posterolateral fusion with screw fixation.

CONCLUSIONS

The spinal axes were corrected with obvious and satisfying realignment effects. The neurologic symptoms disappeared after surgery. The 1-year follow-up period was uneventful. Surgical treatment for SMD multiaxial spine malformation is feasible. Posterior column resection with segmental pedicle screw fixation and complementary fusion provides obvious curative effects for adult patients with neurologic complications.

Posterior-Only Approach with Pedicle Screws for the Correction of Scheuermann's Kyphosis

Study Design

Retrospective study (level of evidence: level 3).

Purpose

The purpose of this study was to evaluate the clinical and radiological results of the posterior-only approach with pedicle screws for the treatment of Scheuermann's kyphosis (SK).

Overview of Literature

The correction of SK with instrumentation can be performed using posterior-only or combined anterior-posterior procedures. With the use of all-pedicle screw constructs in spine surgery, the posterior-only approach has become a popular option for the definitive treatment of SK. In a nationwide study involving 2,796 patients, a trend toward posterior-only fusion with lower complication rates was reported.

Methods

We retrospectively reviewed the data of patients who underwent posterior-only correction for SK between January 2005 and May 2013. Patients with a definite diagnosis of SK who fulfilled the minimum follow-up criterion of 24 months were included. The thoracic kyphosis (T5–T12), lumbar lordosis (L1–S1), and thoracolumbar junction (T10–L2) angles were measured from preoperative, postoperative, and last control radiographs. Sagittal balance, thoracic length, thoracic diameter, Voutsinas index and the sacral slope, pelvic tilt, proximal junction kyphosis, and distal junction kyphosis angles were also measured.

Results

Forty-five patients underwent surgery for the treatment of SK between 2005 and 2013. After applying the exclusion criteria, 20 patients (18 males and 2 females) with a mean age of 19 years were included. The mean thoracic kyphosis angle was 79.8 degrees preoperatively, 44.6 degrees postoperatively, and 44.9 degrees at the last control. There were statistically significant differences between preoperative and postoperative values in the thoracic kyphosis and lumbar lordosis angles, thoracic length, thoracic diameter, and Voutsinas index (p<0.05).

Conclusions

The clinical and radiological results of the current study suggest that posterior-only fusion is an efficient technique for the treatment of SK.

Can MRI Predict Flexibility in Scheuermann Kyphosis Patients?

STUDY DESIGN

Retrospective, blinded analysis of imaging studies.

OBJECTIVE

The aim of this study is compare the use of magnetic resonance imaging (MRI) to lateral radiograph using bolster in the evaluation of Scheuermann kyphosis (SK) curve flexibility measurement.

SUMMARY AND BACKGROUND DATA

The flexibility of the thoracic curve [thoracic kyphosis (TK)] in SK is of primary importance in its preoperative planning. Several methods have been described for SK curve flexibility measurement. The most commonly used method is lateral hyperextension radiography on hard bolster [hyperextension radiograph (HE)]. No current methods use MRI for flexibility assessment.

MATERIALS AND METHODS

Flexibility of TK in SK patients was measured as a difference between standing radiograph and bolster-assisted lateral HE or supine MRI. The sagittal Cobb angle of the TK was measured between the superior endplate of T4 and the inferior endplate of T12 vertebral body. Flexibilities measured by these 2 methods were compared and analyzed using the generalized estimating equation analysis and the correlation analysis.

RESULTS

We assessed 18 SK patients (14 males and 4 females) with mean age of 20.06±6.03 years. The standing TK x-rays showed 83.8±6.1 degrees. On HE, TK curve reduced by 39.3 degrees (95% confidence interval, 35.8-42.9) to 44.5±6.2 degrees (P<0.001). Preoperative MRI images showed TK of 53.8±5.9 degrees which means reduction by 30 degrees (95% confidence interval, 26.6-33.4) from the standing radiographs (P<0.001). Linear dependency between HE and MRI flexibility with a mean difference of 9.3 degrees was found (R=0.61, P<0.001).

CONCLUSIONS

Our study shows that preoperative MRI can be used for SK flexibility assessment with similar predictive value as routinely used bolster-assisted hyperextension lateral radiograph. Consequently, patient exposure to preoperative hyperextension ionizing radiation may be reduced.

Postoperative changes in sacropelvic junction in short-segment angular kyphosis versus Scheuermann kyphosis

PURPOSE

To comparatively evaluate the biomechanical alterations those occur in the sagittal plane of sacropelvic junction in angular kyphosis (AK) and Scheuermann kyphosis (SK) patients after surgery.

METHODS

The spine radiographs of 52 patients operated for short-segment AK (n = 20) or SK (n = 32) were studied. Main outcome measures were sacral slope, pelvic incidence, pelvic tilt, lumbar lordosis, and thoracic kyphosis angles.

RESULTS

In AK group, local and thoracic kyphosis angles, as well as lumbar lordosis angle, showed statistically significant reduction with surgery. Thoracic kyphosis and lumbar lordosis angles were reduced significantly in SK group. Postoperatively, there were significant differences between groups in lumbar lordosis, pelvic tilt angle, and sacral slope (p = 0.021, p = 0.001, and p = 0.027, respectively). Thoracic kyphosis angle and sacral slope were increased, and there was a remarkable correlation between thoracic kyphosis and lumbar lordosis values in the AK group.

CONCLUSIONS

The results of this study suggest that a significant sacropelvic improvement can be achieved by balanced sagittal vertical axis and T1 spinopelvic leading to a good sagittal alignment of spine in patients with AK and SK. Changes seen in morphological parameters after surgery may be closely related with baseline biomechanics and structure of the spine and pelvis. Therefore, further clinical and scientific trials are necessary both to elucidate the biomechanics, their clinical implications, and to develop new techniques and models for spine and pelvis surgery.

Results of the Scoliosis Research Society Morbidity and Mortality Database 2009-2012: A Report From the Morbidity and Mortality Committee

INTRODUCTION

Members of the Scoliosis Research Society are required to annually submit complication data regarding deaths, visual acuity loss, neurological deficit and infection (2012-1st year for this measure) for all deformity operations performed. The purpose of this study is to report the 2012 results and the differences in these complications from the years 2009-2012.

METHODS

The SRS M&M database is a self-reported complications registry of deformity operations performed by the members. The data from 2009-2012, inclusive, was tabulated and analyzed. Differences in frequency distribution between years were analyzed with Fisher's exact test. Significance was set at α = 0.05.

RESULTS

The total number of cases reported increased from 34,332 in 2009 to 47,755 in 2012. Overall mortality ranged from 0.07% in 2011 to 0.12% in 2009. The neuromuscular scoliosis group had the highest mortality rate (0.44%) in 2010. The combined groups' neurological deficit rate increased from 0.44% in 2009 to 0.79% in 2012. Neurological deficits were significantly lower in 2009 compared to 2012 for idiopathic scoliosis >18 years, other scoliosis, degenerative and isthmic spondylolisthesis and other groups. The groups with the highest neurological deficit rates were dysplastic spondylolisthesis and congenital kyphosis. There were no differences in vision loss rates between years. The overall 2012 infection rate was 1.14% with neuromuscular scoliosis having the highest group rate at 2.97%.

CONCLUSION

Neuromuscular scoliosis has the highest complication rates of mortality and infection. The neurological deficit rates of all groups combined have slightly increased from 2009 to 2012 with the highest rates consistently being in the dysplastic spondylolisthesis and congenital kyphosis groups. This could be due to a number of factors, including more rigorous reporting.

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.

Proximal Junctional Kyphosis Following Spinal Deformity Surgery in the Pediatric Patient

Proper understanding and restoration of sagittal balance is critical in spinal deformity surgery, including conditions such as adolescent idiopathic scoliosis and Scheuermann kyphosis. One potential complication following spinal reconstruction is proximal junctional kyphosis. The prevalence of proximal junctional kyphosis varies in the literature, and several patient- and surgery-related risk factors have been identified. To date, the development of proximal junctional kyphosis has not been shown to lead to a negative clinical outcome following spinal fusion for adolescent idiopathic scoliosis or Scheuermann kyphosis. Treatment options range from simple observation in asymptomatic cases to revision surgery with extension of the fusion proximally. Several techniques and technologies are emerging that seek to address and prevent proximal junctional kyphosis.

Comparison of Anteroposterior to Posterior-Only Correction of Scheuermann's Kyphosis: A Matched-Pair Radiographic Analysis of 92 Patients

STUDY DESIGN

Retrospective radiographic benchmark study.

OBJECTIVE

To evaluate the amount of instrumented correction obtained from a combined anterior/posterior (A/P) versus posterior-only (post-only) approach for Scheuermann's kyphosis.

SUMMARY OF BACKGROUND DATA

An A/P approach was thought to optimize correction; however, instrumentation advances using pedicle screws allow treatment through an all-posterior approach.

METHODS

A total of 166 Scheuermann's kyphosis patients were treated between 2 centers: 90 by combined A/P approach at 1 center and 76 by post-only at the second center. From the 166 patients, a matched cohort of 92 (46 from each) was established according to preoperative sagittal (±10°) and hyperextension (HE) Cobb (±10°) measurements and matched for age and gender.

RESULTS

In the matched-pair group, average preoperative sagittal Cobb angles were 75.9° for the A/P group versus 78.8° for the post-only group (p = .2). The HE Cobb angles were similar (52.4° vs. 51.1°; p = .6). They showed similar corrections (33.7° vs. 30.6°; p = .3) and postoperative Cobb measurements (43.4° vs. 47.1°; p = .2) as well. The number of fusion levels was 9 in the A/P group and 12 in the post-only group; the difference yielded significance (p = .02).

CONCLUSIONS

The A/P and post-only approaches averaged similar degrees of correction. The A/P patients were likely to correct more than their preoperative HE sagittal Cobb measurement, whereas the post-only group corrected close to their preoperative HE measurement. The number of fusion levels was larger with the post-only group.

Proximal junctional kyphosis and failure after spinal deformity surgery: a systematic review of the literature as a background to classification development

STUDY DESIGN

Systematic review of literature.

OBJECTIVE

To perform a comprehensive English language systematic literature review of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF), concentrating on incidence, risk factors, health related quality of life impact, prevention strategy, and classification systems.

SUMMARY OF BACKGROUND DATA

PJK and PJF are well described clinical pathologies and are a frequent cause of revision surgery. The development of a PJK classification that correlates with clinical outcomes and guides treatment decisions and possible prevention strategies would be of significant benefit to patients and surgeons.

METHODS

The phrases "proximal junctional," "proximal junctional kyphosis," and "proximal junctional failure" were used as search terms in PubMed for all years up to 2014 to identify all articles that included at least one of these terms.

RESULTS

Fifty-three articles were identified overall. Eighteen articles assessed for risk factors. Eight studies specifically reviewed prevention strategies. There were no randomized prospective studies. There were 3 published studies that have attempted to classify PJK. The reported incidence of PJK ranged widely, from 5% to 46% in patients undergoing spinal instrumentation and fusion for adult spinal deformity. It is reported that 66% of PJK occurs within 3 months and 80% within 18 months after surgery. The reported revision rates due to PJK range from 13% to 55%. Modifiable and nonmodifiable risk factors for PJK have been characterized.

CONCLUSION

PJK and PJF affect many patients after long segment instrumentation after the correction of adult spinal deformity. The epidemiology and risk factors for the disease are well defined. A PJK and PJF scoring system may help describe the severity of disease and guide the need for revision surgery. The development and prospective validation of a PJK classification system is important considering the prevalence of the problem and its clinical and economic impact.

LEVEL OF EVIDENCE

N/A.

Posterior-only correction of Scheuermann kyphosis using pedicle screws: economical optimization through screw density reduction

INTRODUCTION

Posterior-only approach using pedicle screws' fixation has emerged as the preferred surgical technique for Scheuermann kyphosis (SK) correction. Insertion of multiple pedicle screws while increasing stability increases also the risk of complications related to screw malpositioning and surgical cost. The optimal screw density required in surgical correction of SK remains unclear. This study compares the safety and efficacy of low screw density (LSD) versus high screw density (HSD) technique used in posterior-only correction of SK.

METHODS

Twenty-one patients underwent surgical correction of SK between 2007 and 2011 and were reviewed after a mean of 29 months. HSD technique (i.e., 100 % of available pedicles, averaged 25.2 ± 4 screws) was used in 10 cases and LSD technique (i.e., 54-69 % of available pedicles in a pre-determined pattern, averaged 16.8 ± 1.3 screws; p < 0.001) was used in 11 cases. Kyphosis correction was assessed by comparing thoracic kyphosis, lumbar lordosis and sagittal balance on preoperative and postoperative radiographs. Cost saving analysis was performed for each group.

RESULTS

Preoperative thoracic kyphosis, lumbar lordosis and sagittal balance were similar for both groups. The average postoperative kyphosis correction was similar in both HSD and LSD groups (29° ± 9° vs. 34° ± 6°, respectively; p = 0.14). Complication occurred in four patients (19 %) in the HSD group and in two patients (9 %) in the LSD group (p = 0.56). Three patients required re-operation. Compared to HSD using LSD saves 4,200 pounds sterling per patient in hardware and 88,200 pounds sterling for the entire cohort.

CONCLUSION

LSD technique is as safe and effective as HSD technique in posterior-only correction of SK. Implant-related cost could be reduced by 32 %.