Preoperative Pelvic Incidence Research Articles

Spinal Instrumentation in Growing Children Retards the Natural Development of Pelvic Incidence.

Pelvic incidence increases gradually throughout growth until skeletal maturity. Growing rod instrumentation has been suggested to have a stabilizing effect on the development of the normal sagittal spinal alignment. The purpose of this study is to determine the effect of fixed sagittal plane caused by dual growing rod instrumentation on the natural progression of sagittal spinopelvic parameters in children with idiopathic or idiopathic-like early onset scoliosis. Hospital records of children with growing rod instrumentation from 4 separate institutions were reviewed retrospectively. Inclusion criteria were idiopathic or idiopathic-like early onset scoliosis, treatment with dual growing rods with lower instrumented vertebra L4 or upper and more than 2 years of follow-up. Instrumentation levels, magnitudes of major curve, thoracic kyphosis (T2-T12), lumbar lordosis (L1-S1) and pelvic incidence were recorded from preoperative and postoperative standing whole-spine radiographs. Estimated pelvic incidence was also calculated for each patient as if their spines had not been instrumented using the previous normative data. A total of 37 patients satisfied the inclusion criteria. Average age at initial surgery was 7.4±1.8 years (range, 4 to 12 y). Mean follow-up time was 71±26 months (range, 27 to 120 mo). Mean preoperative Cobb angle of 59±13.5 (range, 30 to 86) degrees was reduced to 35.1±17.5 (range, 11 to 78) degrees at the last follow-up. Mean preoperative T2-T12 kyphosis angle was 46.2±14.9 degrees (range, 22 to 84 degrees). At the latest follow-up, it was 44.8±16.2 degrees (range, 11 to 84 degrees) (P=0.93). Mean L1-S1 lordosis angle was 50.5±10.7 degrees (range, 30 to 72 degrees) preoperatively. At the latest follow-up, mean L1-S1 lordosis angle was 48.8±12.7 degrees (range, 26 to 74 degrees) (P=0.29). Mean preoperative pelvic incidence was 45.7±7.9 degrees (range, 30 to 68 degrees). At the latest follow-up, it was 46.7±8.4 degrees (range, 34 to 72 degrees) (P=0.303). The estimated average pelvic incidence was 49.5 degrees (P=0.012). Previously reported developmental changes of the sagittal spinal parameters were not observed in children who underwent posterior spinal instrumentation. Our findings suggest that spinal instrumentation impedes the natural development of the sagittal spinal profile. Level IV-this is a retrospective case-series.

Effects of total hip arthroplasty on spinal sagittal alignment and static balance: a prospective study on 28 patients.

The aim of this study was to investigate postoperative changes in spinal sagittal alignment and postural balance in patients with hip-spine syndrome (HSS) and to verify whether any significant correlation exists between these changes and improvement of low back pain (LBP) symptoms following total hip replacement (THR) surgery. Twenty-eight consecutive patients with HSS undergoing unilateral THR were prospectively enrolled. Whole spine X-rays were obtained before surgery and 6months after surgery. The following parameters were measured: cervical lordosis, thoracic kyphosis, lumbar lordosis, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and sagittal vertical axis (C7 SVA). Patients underwent pre- and postoperative postural balance assessment (950-460 BioSwayTM system; clinical test of sensory integration-CTSIB, limit of stability test-LOS) and patient reported outcome measures assessment (Short Form-36, SF-36, Oswestry Disability Index, ODI, Visual Analog Scale, VAS and Western Ontario and McMaster Universities Arthritis Index, WOMAC). Mean age of the patients was 61.7±6.4. Median (interquartile range, IQR) pre-operative PI and PT were 50.0 (35.0, 60.0) and 11.0 (7.0, 23.0), respectively; lumbar lordosis was 49.0 (41.0, 68.0) and SVA 5.0 (-11.0, 41.0). No significant changes in sagittal alignment were observed postoperatively. Median LBP VAS decreased from 6.0 (5.0, 7.0) to 3.0 (2.0, 4.0) and ODI from 54.0 (39.0, 64.0) to 34.0 (26.0, 48.0) (p<0.001). Median CTSIB improved from 1.22 (1.07, 1.45) to 1.01 (0.80, 1.19) and LOS from 46.0 (42.0, 58.0) to 37.0 (32.0, 39.0) postoperatively. No significant correlation was noted between postoperative changes in spinal sagittal alignment or postural balance and improvement of LBP VAS and ODI scores. Our study demonstrated an improvement in LBP levels (VAS and ODI) and postural balance in patients with HSS following THR surgery. No significant changes have been noted in radiographic spinal sagittal alignment postoperatively. The improvement in LBP levels does not correlate with post-operative changes in spinopelvic alignment or postural balance.

Factors associated with improvement in sagittal spinal alignment after microendoscopic laminotomy in patients with lumbar spinal canal stenosis.

OBJECTIVE Little is known about the relationship between sagittal spinal alignment in patients with lumbar spinal canal stenosis (LSS) and objective findings such as spinopelvic parameters, lumbar back muscle degeneration, and clinical data. The purpose of this study was to identify the preoperative clinical and radiological factors that predict improvement in sagittal spinal alignment after decompressive surgery in patients with LSS. METHODS The records of 61 patients with LSS who underwent microendoscopic laminotomy and had pre- and postoperative clinical data collected were retrospectively reviewed. Spinopelvic parameters, including sagittal vertical axis (SVA), lumbar lordosis (LL), sacral slope, pelvic tilt, and pelvic incidence (PI), were evaluated. On T2-weighted MRI, the cross-sectional area and the percentage of fat infiltration of the paravertebral muscles (PVMs) before surgery were calculated. For patients with preoperative SVA > 40 mm (n = 30), the correlation between SVA improvement and preoperative clinical and radiographic parameters was calculated. RESULTS SVA improvement correlated with preoperative LL (r = -0.39) and PI -LL (r = 0.54). Multiple regression analysis showed that preoperative PI -LL (beta = 0.62; p < 0.01) and symptom duration (beta = -0.40; p < 0.05) were independently associated with SVA improvement. The percentage of fat infiltration of the PVM at L4-5 was significantly greater in patients with preoperative SVA ≥ 40 mm than in those patients with SVA < 40 mm. CONCLUSIONS Preoperative PI -LL and symptom duration were independently associated with SVA improvement in LSS patients with forward-bending posture. PVM degeneration at the lower lumbar level was significantly greater among patients with preoperative SVA ≥ 40 mm than in patients with SVA < 40 mm.

Overcorrection of lumbar lordosis for adult spinal deformity with sagittal imbalance: comparison of radiographic outcomes between overcorrection and undercorrection.

To determine the correlation of the difference between postoperative lumbar lordosis (LL) and ideal LL with the sagittal vertical axis (SVA) at the final follow-up in patients with adult spinal deformity (ASD). Fifty-one patients with degenerative lumbar kyphosis (DLK) (mean age 66.5years) who underwent surgical correction with a minimum 2-year follow-up were evaluated. Based on the difference between postoperative LL and ideal LL using the Korean version of Legaye's formula, we divided the 51 patients into two groups: overcorrection (degree of postoperative LL>ideal LL) and undercorrection (degree of postoperative LL<ideal LL). Our clinical series of patients comprised 24 in the overcorrection and 27 in the undercorrection group. No significant differences were found in preoperative pelvic incidence (PI 52.6° vs. 57.3°), sacral slope (SS 23.3° vs. 18.3°), LL (-6.9° vs. -2.3°), thoracic kyphosis (TK 4.7° vs. 4.9°) and SVA (140 vs. 139mm) except pelvic tilt (PT 29.4° vs. 39.0°), between the two groups. All the patients in the overcorrection group and 16 in the undercorrection group achieved postoperative optimal sagittal balance based on SVA≤50mm. In addition, significant differences in PT (10.5° vs. 26.7°), SS (42.1° vs. 30.6°), LL (-64.3° vs. -37.1°), TK (22.6° vs. 15.8°), and SVA (-1 vs. 41mm) between the two groups were observed postoperatively. Furthermore, four patients (16.7%) in the overcorrection group and eight (50%) in the undercorrection group had sagittal decompensation at the final follow-up. Our results showed that the difference between postoperative LL and ideal LL had a significant correlation with postoperative and final follow-up SVA in our clinical series. Overcorrection of LL is an effective treatment modality to maintain optimal sagittal alignment in patients with DLK; this suggests that it should be considered in preoperative planning for patients with ASD with sagittal imbalance.

Correlation between preoperative spinopelvic alignment and risk of proximal junctional kyphosis after posterior-only surgical correction of Scheuermann kyphosis

Background ContextSurgical correction of Scheuermann kyphosis (SK) is challenging and plagued by relatively high rates of proximal junctional kyphosis and failure (PJK and PJF). Normal sagittal alignment of the spine is determined by pelvic geometric parameters. How these parameters correlate with the risk of developing PJK in SK is not known. PurposeThe study aimed to investigate the relationship between preoperative and postoperative spinopelvic alignment and occurrence of PJK and PJF. Study Design/SettingThis is a retrospective observational cohort study. Patient SampleThe sample included 37 patients who underwent posterior correction of SK from January 2006 to December 2012. Outcome MeasuresThe outcome measure was correlation analysis between preoperative and postoperative spinopelvic alignment parameters and the development of PJK over the course of the study period. MethodsWhole spine x-rays obtained before surgery, 3 months after surgery, and at the latest follow-up were analyzed. The following parameters were measured: thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). The development of PJK was considered the primary end point of the study. Patient population was split into a control and a PJK group; repeated-measures analysis of variance was used to assess group and time differences. ResultsSeven patients developed PJK over the study period. Although the severity of the preoperative deformity (TK) did not differ significantly between the two groups, preoperative PI was significantly higher in the PJK group (51.9°C±8.6°C vs. 42.7°C±8.8°C, p=.018). Postoperative correction of TK was similar between the two groups (39.3% and 41.2%, p=.678) and final LL did not differ as well (53.6°C±9.2°C vs. 51.3°C±11.5°C). However, because PJK patients had larger preoperative PI values, a significant deficit of LL was observed at final follow-up in this group compared with the control group (ΔLL −10.5°C±9.8°C vs. 0.6°C±10.5°C, p=.013). ConclusionsScheuermann kyphosis patients who developed PJK appeared to have a significant postoperative deficit of LL (lumbopelvic mismatch). Lumbar lordosis decreases after surgery following correction of TK; therefore, TK correction should be planned according to preoperative PI values to avoid excessive reduction of LL in patients with higher PI values.

Characteristics and Mechanisms of Adjusting Spinopelvic Sagittal Balance in Patients with Thoracic and Thoracolumbar Kyphosis

Introduction This study determined the mechanisms of adjusting trunk sagittal balance and the impact of surgery on spinopelvic sagittal morphology and alignment in patients with thoracic and thoracolumbar kyphosis. Materials and Methods Whole spine and standing lateral radiographs of 49 Chinese patients with thoracic and thoracolumbar kyphosis were obtained before surgery, immediately after surgery, and in the final follow-up. A total of 171 asymptomatic Chinese adults were recruited as controls. The age at which the patients developed kyphotic deformity was recorded. The pelvic and spinal parameters were measured and the correlations of all parameters were analyzed. Results The mean age at which the patients developed kyphosis was 7.1 years. Preoperative mean pelvic incidence was 35.1 degrees, and mean pelvic tilt was −0.1 degrees, significantly less than those of normal subjects. Preoperative mean lumbar lordosis was 68.0 degrees, significantly higher than that of normal subjects. After surgery, kyphosis and lumbar hyperlordosis were significantly corrected, however, the preoperative and postoperative pelvic sagittal morphology and alignment made no difference, even in the final follow-up. There were no correlations between spinal and pelvic parameters before surgery. In the final follow-up, the correlations were recovered. Conclusion The mechanisms of adjusting the trunk sagittal balance in patients with thoracic and thoracolumbar kyphosis not only including pelvis anteverting, but also lumbar hyperlordosis. The latter serves as the main mechanism once skeletal maturation has been established. Although kyphosis and lumbar hyperlordosis were corrected by surgery, pelvic sagittal morphology remained unchanged. Surgery can reestablish the spinal sagittal balance and recover the correlations between spinal and pelvic parameters.

Radiological improvements in global sagittal alignment after lumbar decompression without fusion.

A retrospective, radiographical study. To evaluate short-term radiological changes in sagittal alignment after lumbar decompression without fusion for lumbar canal stenosis. Although the importance of global sagittal balance is underscored recently, little is known about the changes in sagittal alignment after lumbar canal decompression. We retrospectively reviewed 88 patients who underwent lumbar decompression without fusion at a single institution between November 2008 and May 2013, with a minimum follow-up of 5 months. Standing radiographs at the preoperative period and the final follow-up were assessed. Radiological parameters included the sagittal vertical axis (SVA), lumbar lordosis (LL), pelvic tilt, pelvic incidence (PI), occipital 7th cervical angle, and thoracic kyphosis, which were measured by 2 spine surgeons. The Zurich Claudication Questionnaire and visual analogue scale scores were obtained to assess the patient-based clinical outcomes. Both LL and thoracic kyphosis significantly increased postoperatively, whereas SVA, PI-LL (PI minus LL), and pelvic tilt significantly decreased (P<0.05). There were no significant differences between the preoperative and postoperative occipital 7th cervical angle and PI. The amount of increment in LL was greater in patients with small preoperative LL. The improvement in SVA was greater in those with a large preoperative SVA. The Zurich Claudication Questionnaire and visual analogue scale scores showed no significant correlation with the radiological parameters. Lumbar decompression without fusion can induce a reactive improvement in the lumbar and global sagittal alignment even if a sagittal imbalance exists preoperatively. 4.

Restoration of the spinopelvic sagittal balance in isthmic spondylolisthesis: posterior lumbar interbody fusion may be better than posterolateral fusion

Background contextMore and more orthopedic surgeons recognize the importance of the sagittal balance of the spine. PurposeTo analyze the pre- and postoperative sagittal and deformity parameters of low-grade isthmic spondylolisthesis and evaluate the effect of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) on spinopelvic sagittal balance. Study designNonrandomized controlled prospective study with a historical control. Patient sampleA total of 99 patients with low-grade L5–S1 isthmic spondylolisthesis were treated surgically; 36 patients (mean age, 60.2±5.2 years) received the PLF operation, and 63 patients (mean age, 57.1±6.9 years) chose the PLIF operation. The healthy control group was composed of 60 volunteers (mean age, 44.5±8.4 years). Outcome measuresThe pre- and postoperative spinopelvic and deformity parameters. MethodsAll patients had radiographs that allowed measurement of spinopelvic parameters before and after the operation. All the spinopelvic and deformity parameters were measured. Two radiologists measured the parameters with the Cobb method. ResultsAll of the preoperative spinopelvic parameters showed no difference between the PLIF and PLF groups in this study (p>.05). In both of the operation groups, the preoperative pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), and L5 incidence (L5I) were significantly higher than in the control group (p<.01); the height of the intervertebral disc (HOD) was significantly lower than the controls. There were no significant differences in PT among PLIF, PLF, and control groups after the operation (p>.05). LL increased in the PLIF group and decreased in the PLF group. The slip degree (SD) and L5I were restored significantly in both groups. The HOD of the PLIF group increased 5.04 mm, the postoperative HOD of the PLF group had no significant change. In both PLIF and PLF groups, the correction of SD was correlated with the change of LL (r=−0.398, p=.007; r=0.365, p=.022). The restoration of HOD in the PLIF group correlated with the change of LL (r=0.334, p=.011). No significant differences could be found between the short-term clinical outcomes of the PLF and PLIF. ConclusionEither PLF or PLIF would lead a great change in spinopelvic parameters and deformity parameters. The decrease of PT may be an important role for the short-term surgical outcome. The PLIF could increase the LL and form a more reasonable sagittal alignment. From the point of the sagittal spinopelvic balance, the PLIF may be better than the PLF for patients with isthmic spondylolisthesis.

Radiographical Predictors for Postoperative Sagittal Imbalance in Patients With Thoracolumbar Kyphosis Secondary to Ankylosing Spondylitis After Lumbar Pedicle Subtraction Osteotomy

A retrospective radiographical study. To identify the radiographical predictors for sagittal imbalance in patients with thoracolumbar kyphosis secondary to ankylosing spondylitis (AS) after 1-level lumbar pedicle subtraction osteotomy (PSO). Few studies had correlated the preoperative sagittal parameters with postoperative sagittal alignments to determine the radiographical predictors for postoperative sagittal imbalance in patients with AS after 1-level lumbar PSO. Thirty-six patients with thoracolumbar kyphosis secondary to AS who underwent 1-level lumbar PSO were recruited with a minimal follow-up of 24 months (mean = 27.4 mo; range, 24-53 mo). Correlation analysis and subsequent stepwise multiple regression analysis were used to evaluate the correlations between preoperative parameters, including global kyphosis, local kyphosis, thoracic kyphosis, thoracolumbar Cobb angle, lumbar lordosis, pelvic incidence (PI), pelvic tilt, sacral slope, and sagittal vertical axis (SVA), as well as SVA at the last follow-up. All these patients were further divided into 2 groups according to the PI value (group A: PI >50°; group B: PI ≤50°). The correction outcomes were compared between these 2 groups. The preoperative SVA was not significantly different between group A and group B (157.6 mm vs. 124.5 mm; P> 0.05), and both groups had similar magnitudes of kyphosis corrections at the last follow-up (global kyphosis: 42.9° vs. 46.1°; local kyphosis: 42.7° vs. 40.5°; lumbar lordosis: 35.7° vs. 43.0°). However, group A patients had significantly larger SVA at the last follow-up (73.2 mm vs. 28.7 mm; P< 0.05) and a higher incidence of postoperative sagittal imbalance (77.8% vs. 25.9%; P< 0.05) than those in group B. The stepwise multiple regression analysis demonstrated that both preoperative SVA and PI were significant independent predictors of postoperative sagittal alignments, which explained 52.0% and 9.7% of the variability of SVA at the last follow-up, respectively. Patients with AS with either larger preoperative SVA or larger PI are more likely to experience failed sagittal realignments after 1-level lumbar PSO. For these patients, additional osteotomies may be recommended for satisfactory correction outcomes. 4.

Analysis of Spinopelvic Sagittal Alignment in Patients With Thoracic and Thoracolumbar Angular Kyphosis

Retrospective and radiological analysis of spinopelvic sagittal alignment in Chinese patients with thoracic and thoracolumbar kyphosis. To determine the impact of thoracic and thoracolumbar kyphosis on pelvic sagittal morphology and the mechanisms of adjusting trunk sagittal balance. Previous studies have reported the normative values of pelvic sagittal parameters and classification of normal patterns of sagittal curvature, but no study has analyzed the impact of thoracic and thoracolumbar kyphosis on pelvic sagittal morphology and the mechanisms of maintaining the sagittal balance. Whole spine and standing lateral radiographs of 49 Chinese patients with thoracic and thoracolumbar kyphosis were obtained before surgery, immediately after surgery, and in the final follow-up. The pelvic and spinal parameters were measured and the correlations of all parameters were analyzed. A descriptive analysis characterizing these parameters and a multivariate analysis were performed. The patients had a mean age of 30.3 years, whereas the mean age at which the patients who developed kyphosis was 7.1 years. Preoperative pelvic incidence was significantly less than that of normal subjects, and there was no difference in the preoperative, in the immediate postoperative, and in the final follow-up radiographs. The magnitude of kyphosis and the levels involved were independent factors of pelvic incidence. Pelvis anteversion and lumbar hyperlordosis were the mechanisms of adjusting the trunk sagittal balance. Although kyphosis and sagittal imbalance was corrected by surgery, pelvic sagittal morphology remained unchanged. Thoracic and thoracolumbar angular kyphosis occurring during the growth period will lead to abnormal pelvic morphology. The greater the kyphotic angle and lower the kyphotic levels, the greater the impact on the pelvic morphology during skeletal maturation. The mechanisms of adjusting the trunk sagittal balance not only include pelvis anteverting, but also lumbar hyperlordosis. The latter serves as the main mechanism once skeletal maturation has been established. After skeletal maturation, surgery can re-establish the spinal sagittal balance but not the pelvis morphology. 3.

Changes in Thoracic Kyphosis Negatively Impact Sagittal Alignment After Lumbar Pedicle Subtraction Osteotomy

Consecutive, multicenter retrospective review. To evaluate if change in thoracic kyphosis (TK) has a positive or negative impact on spinopelvic alignment after lumbar pedicle subtraction osteotomy (PSO) with short fusions. In the setting of sagittal malalignment, the effect of large vertebral resections can now be anticipated in long fusions, but their impact on unfused segments (reciprocal changes [RC]) remains poorly understood. A total of 34 adult patients (mean age = 54 years; SD = 12) who underwent lumbar PSO with upper instrumented vertebra below T10 were included. Radiographic analysis included pre- and postassessment of TK, lumbar lordosis (LL), sagittal vertical axis (SVA), T1 spinopelvic inclination (T1SPI), pelvic tilt (PT), and pelvic incidence (PI). Final SVA and PT were analyzed to determine successful realignment. RC in the thoracic spine was designated favorable or unfavorable on the basis of impact on final SVA and PT. Mean PSO resection was 26°. LL increased from 20° to 49° (P < 0.001). SVA improved from 14 to 4 cm (P < 0.001), and PT improved from 33° to 25° (P < 0.001). Mean increase in TK was 13° (P = 0.002) but was unchanged in 11 patients. Five patients had a favorable RC, and 18 patients had an unfavorable RC. Unfavorable RC was attributed to junctional failure in 6 of 18 patients. Significant differences in the unfavorable RC group included age and greater preoperative PT, PI, SVA, and T1SPI. Significant postoperative alignment changes can occur through unfused thoracic spinal segments after lumbar PSO. Unfavorable RC may limit optimal correction and lead to clinical failures. Risk factors for unfavorable thoracic RC include older patients, larger preoperative PI and PT, and worse preoperative T1SPI and are not simply due to junctional failure. Care should be taken with selective lumbar fusion and PSO in older patients and in those with severe preoperative spinopelvic parameters.

A Surgical Option for Multilevel Anterior Lumbar Interbody Fusion with Ponte Osteotomy to Achieve Optimal Lumbar Lordosis and Sagittal Balance

ObjectiveTo document lumbar lordosis (LL) of the spine and its change during surgeries with the different height but the same angle setting of the anterior cage. Additionally, we attempted to determine if sufficient LL is achieved at different cage heights and to quantify the change in LL during multi-level anterior lumbar interbody fusion (ALIF).MethodsThe medical records and radiographs of 42 patients who underwent more than 2 level ALIFs between 2008 and 2009 were retrospectively reviewed. We evaluated 3 parameters seen on lateral whole spine radiographs : LL, pelvic incidence (PI), and sagittal vertical axis (SVA). The mean follow-up time was 28.1 months and the final follow-up radiographs of all patients were reviewed at least 2 years after surgery. Statistical analysis was performed using the paired t-tests.ResultsLumbar lordosis had changed up to 30 degrees immediately and 2 years after surgery (preoperative mean LL, SVA : 22.45 degrees, 112.31 mm; immediate postoperative mean LL, SVA : 54.45 degrees, 37.36 mm; final follow-up mean LL, SVA : 49.56 degrees, 26.95 mm). Our goal of LL is to obtain as much PI as possible, preoperative mean PI value was 55.38±3.35. The pre-operative and two year post-surgery follow-up mean of the Japanese Orthopedic Association score were 9.2±0.6 and 13.2±0.6 (favorable outcome rate : 95%), respectively. In addition, we were able to obtain good clinical outcomes and sagittal balance with a subsidence rate of 22.7%.ConclusionWe were able to achieve sufficient LL, such that it was similar to the PI, utilizing multi-level ALIF with the use of a tall cage with the same angle setting of the cage. We have found out that achieving sufficient lumbar lordosis and sagittal balance require an anterior lumbar cage with high angle and height.

Is there any correlation between the preoperative parameters and correction loss in patients operated for hyperkyphosis?

Preoperative, postoperative, and latest follow-up data of sagittal balance and spinopelvic parameters of our patients treated surgically for hyperkyphosis were evaluated retrospectively, to determine whether there is any correlation between the preoperative pelvic incidence and postoperative correction loss. Totally 33 patients (18 females) who were operated for hyperkyphosis and, were reached at the latest follow-up were included in the study. Age at operation, gender, date of operation, etiology and level of the deformities, instrumentation, and graft types were noted in detail. The kyphosis angles were measured by the Cobb method. The preoperative and postoperative spinopelvic parameters (pelvic incidence, sacral slope, and pelvic tilt) were recorded. The average follow-up was 4 years (range 3-8 years). The mean age at operation was 21 years (range 14-40 years). Scheuermann kyphosis was diagnosed as the etiological factor in 18 patients (53%). The mean preoperative kyphosis angle was 76° (range 55-98°), which decreased postoperatively to 38° (range 20-55°) (p<0.05). The mean kyphosis angle two years postoperatively was 41° (p>0.05). Preoperative and latest follow-up spinopelvic parameters were also not significantly different. Furthermore, no correlation could be found between the age at operation, instrumentation level, spinopelvic parameters, and correction loss. There is no correlation between the preoperative pelvic incidence and postoperative correction loss in patients treated surgically for hyperkyphosis. Further studies with larger sample size and longer follow-up should be conducted.