Preoperative increased pronation angle of the first metatarsus associated with correction loss after hallux valgus surgery: A semi-weight-bearing computed tomography study.

BACKGROUND: The effect of preoperative first metatarsal pronation on postoperative prognosis of hallux valgus (HV) surgery is under investigation. Utilizing semi-weight-bearing computed tomography, the preoperative pronation angle was assessed to quantify its impact on postoperative prognosis. METHODS: In a retrospective analysis of 31 feet, those with re-increased hallux valgus angle postoperatively were classified as the non-maintained group, and the remainder as the maintained group. Preoperative pronation angles were compared to establish a threshold. Subsequently, feet were re-classified into high or low-pronation categories. The relative risk of non-maintenance in high-pronation category was calculated. RESULTS: The non-maintained group exhibited a significantly higher preoperative pronation angle (p = 0.021), with a 28.4º threshold. The high-pronation category had a relative risk of 2.34 for non-maintenance. CONCLUSIONS: Increased preoperative first metatarsal pronation angle is associated with correction loss after HV surgery. Utilizing sWBCT to measure the pronation angle provides valuable insights into postoperative prognosis. LEVEL OF EVIDENCE: III.

Satisfactory immediate spontaneous correction may not mean satisfactory final results for moderate TL/L curves after selective thoracic fusion in AIS patients.

BACKGROUND: Few studies have focused on the chronic spontaneous behavior of the unfused TL/L curve during follow-up. The purpose of the present study was to explore the behavior of the unfused TL/L curve during a long-term follow-up to identify the risk factors for correction loss. METHODS: Sixty-four age-matched female AIS patients undergoing selective thoracic fusion were enrolled. Patients were divided into 2 groups according to whether there was correction loss. Risk factors for correction loss of the unfused TL/L curves were analyzed. The relationship and difference between the immediate postoperative thoracic and TL/L Cobb angles were explored. RESULTS: The TL/L Cobb angle was 28.17° before surgery, 8.60° after surgery, and 10.74° at the final follow-up, with a correction loss of 2.14°. Each subgroup contained 32 cases. A smaller postoperative TL/L Cobb angle was the only risk factor that was independently associated with TL/L correction loss. In the LOSS group, there was a significant difference and no correlation between the immediate postoperative TL/L and the thoracic Cobb angle. In the NO-LOSS group, there was a moderate correlation and no difference between them. CONCLUSION: A smaller immediate postoperative TL/L Cobb angle may have been associated with TL/L correction loss during the long-term follow-up. Thus, good immediate postoperative spontaneous correction may not mean a satisfactory outcome at the final follow-up after STF. Mismatch between thoracic and TL/L Cobb angles immediately after surgery may also be related to correction loss of the unfused TL/L curves. Close attention should be paid in case of deterioration.

Correction loss following short-segment posterior fixation for traumatic thoracolumbar burst fractures related to endplate and intervertebral disc destruction.

BACKGROUND: There has been widespread use of short-segment posterior fixation (SSPF) for traumatic thoracolumbar burst fractures. The relationship between the destruction of the vertebral endplate and adjacent disc and postoperative correction loss has been studied in only a few studies. This study investigated the risk factors for correction loss following SSPF. METHODS: Forty-eight patients (mean age 35.0 years) who underwent SSPF for thoracolumbar burst fractures were enrolled. The mean follow-up period was 25.7 months (12-98 months). The neurological status and postoperative back pain were assessed by the medical records. Segmental kyphotic angle (SKA) and anterior vertebral body height ratio (AVBHR) were measured radiographically to assess indirect vertebral body reduction and local kyphosis. Preoperative Sander's traumatic intervertebral disc lesion (TIDL) classification and AO classification were used to evaluate the severity of disc and vertebral endplate injury. The corrective loss was considered present if ΔSKA was ≥10°. A multivariate logistic regression analysis was performed to identify the risk factors associated with postoperative loss of correction. RESULTS: The fracture distribution was as follows: 10 at T12, 17 at L1, 10 at L2, 9 at L3, and 2 at L4. Vertebral fractures were classified in the following way: A3 in 13 patients, A4 in 11, B1 in 11, and B2 in 13. In 47 patients (98%), a union of the fractured vertebrae was achieved. SKA and AVBHR improved significantly after surgery from 11.6° to 3.5° and from 67.2 to 90.0%, respectively. However, the correction loss at follow-up was 10.4° and 9.7%, respectively. Twenty patients (42%) had severe TIDL (grade 3). Postoperative ΔSKA and ΔAVBHR were significantly higher in patients with TIDL grade 3 than with TIDL grade 0-2. The presence of cranial TIDL grade 3 and older age were significant risk factors for ΔSKA ≥10° on multivariate logistic regression analysis. All patients could walk at follow-up. TIDL grade 3 and ΔSKA ≥10° were associated with severe postoperative back pain. CONCLUSIONS: Risk factors for loss of correction after SSPF for thoracolumbar burst fractures were severe disc and endplate destruction at the time of injury and older age.

Closed-wedge high tibial osteotomy is more advantageous to maintain the correction than open-wedge high tibial osteotomy in osteopenic patients.

PURPOSE: To compare the incidence of correction loss and survival rate between closed-wedge and open-wedge high tibial osteotomies (CWHTO and OWHTO, respectively) in patients with osteopenic and normal bone. METHODS: Retrospective review was conducted for 115 CWHTOs and 119 OWHTOs performed in osteopenic patients [- 2.5 < Bone mineral density (BMD) T scores ≤ - 1] and 136 CWHTOs and 138 OWHTOs performed in normal patients (BMD T score > - 1) from 2012 to 2019. Demographics were not different between CW- and OWHTOs in osteopenic and normal patients (n.s., respectively). Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and posterior tibial slope (PTS) were evaluated pre- and postoperatively (2 weeks after HTO). The occurrence of hinge fractures was investigated using radiographs taken on the operation day. The correction change was calculated as the last follow-up value minus postoperative MPTA. Correction loss was defined when the correction change was ≥ 3°. The survival rate (failure: correction loss) was investigated. RESULTS: There were no significant differences in the pre and postoperative MA, MPTA, PTS, and value changes between CW- and OWHTOs in osteopenic and normal patients (n.s., respectively); the incidence of unstable hinge fractures also did not differ significantly (CWHTO vs. OWHTO = 7 vs. 7.6% in osteopenic patients; 2.9 vs. 3.6% in normal patients; n.s., respectively). The average correction change (CWHTO = - 0.6°, OWHTO = - 1.3°, p = 0.007), incidence of correction loss (CWHTO = 1.7%, OWHTO = 9.2%, p = 0.019), and 5-year survival rates (CWHTO = 98.3%, OWHTO = 90.8%, p = 0.013) differed significantly in osteopenic patients; there were no significant differences in these results in normal patients (n.s., respectively). CONCLUSION: CWHTO was more advantageous than OWHTO regarding the correction loss in osteopenic patients. Intra- and postoperative care that consider poor bone quality will be required when performing OWHTOs in osteopenic patients. LEVEL OF EVIDENCE: III.

Postoperative loss of correction after combined posterior and anterior spinal fusion surgeries in a lumbar burst fracture patient with Class II obesity.

Background: When treating thoracolumbar fractures with severe cranial endplate injury but no or slight caudal endplate injury, it is debatable whether anterior fusion should be performed only for the injured cranial level, or for both cranial and caudal levels. We report an unexpected postoperative correction loss after combined multilevel posterior and single-level anterior fusion surgery in a patient with obesity. Case Description: A 28-year-old male with Class II obesity was brought to the emergency room with an L1 burst fracture with spinal canal involvement. Cranial endplate injury was severe, whereas caudal endplate injury was mild. The first surgery with 1-above 1-below posterior fixation failed to achieve sufficient stability; thus, additional surgeries (3-above 3-below posterior fixation and single-level T12-L1 anterior fusion) were performed. Postoperatively, the local kyphosis angle (LKA) between T12 and L2 was 22° in the lateral lying position and 29° in the standing position. Twenty-one-month post surgery, bony fusion between T12 and L1 was observed, and the LKA was 28° in both the lateral lying and standing positions. After posterior implants were removed 24 months after the surgery, significant correction loss both at the T12-L1 segment (6°) and L1-L2 segment (6°) occurred, and LKA was 40° at the final follow-up. Conclusion: In this patient, an intense axial load due to excessive body weight was at least one of the causes of postoperative correction loss. Postural differences in LKA may be useful to evaluate the stability of thoracolumbar fractures after fusion surgery and to predict postoperative correction loss.

Increased proximal vertebral rotation is associated with shoulder imbalance after posterior spinal fusion for severe adolescent idiopathic scoliosis.

PURPOSE: Residual shoulder imbalance is associated with suboptimal outcomes following the surgical correction of adolescent idiopathic scoliosis (AIS) including poor patient satisfaction. In this retrospective study, we evaluate the radiographic parameters and the relationship between the global and local indices of spinal alignment with shoulder balance pre- and postoperatively utilizing EOS imaging and 3D reconstruction. METHODS: A retrospective radiographic analysis was performed on patients with AIS, treated with posterior spinal fusion. Postoperative radiographs were obtained immediately following surgery, at 6 months and final follow-up over 2 years postoperatively. 3D Radiographic measurements included in the coronal plane radiographic shoulder height difference (RSHD), proximal thoracic Cobb angle (PT) and main thoracic Cobb (MT), in the sagittal plane T4-T12 kyphosis, T12-L5 lordosis, in the axial plane proximal thoracic (PT AVR) and main thoracic apical vertebral rotation (MT AVR). RESULTS: Sixty-six patients were included (63 females) with an average main thoracic curvature of 76 degrees. RSHD averaged 14 mm ± 14 preoperatively, -15 mm ± 12 postoperatively, -8.5 mm ± 11 at 6 months, and -8.3 mm ± 8.7 at final follow-up, respectively. Statistical analysis revealed a significant correlation between RSHD and proximal thoracic Cobb angle, between RSHD and proximal thoracic apical vertebral rotation (PTAVR) (r > 0.20, p < 0.05). CONCLUSION: The significant correlation presented in this study suggests that PT Cobb angle and PT AVR are involved in postoperative shoulder imbalance. THE LEVEL OF EVIDENCE: Level 4.

The Radiological Complications of Short-Segment Pedicle Screw Fixation Combined with Transforaminal Interbody Fusion in the Treatment of Unstable Thoracolumbar Burst Fracture: A Retrospective Case Series Study in Vietnam.

Background: The radiological complications including correction loss and hardware failure of short segment posterior pedicle screw fixation in the treatment of unstable thoracolumbar burst fractures remain a main concern. Several procedures aiming to reinforce the anterior column have been introduced to solve these limitations, including transforaminal interbody fusion (TIF). The purposes of this study were to evaluate the radiological complications of short-segment pedicle screw fixation in combination with transforaminal interbody fusion in the treatment of unstable thoracolumbar burst fractures. Methods: This retrospective case series study enrolled patients with isolated unstable thoracolumbar burst fractures, who were treated by posterior short fixation with TIF between January 2013 and January 2017. Patients were followed up for a minimum of one and half years. For evaluation of correction loss, % loss of anterior vertebral body height (%AVB), vertebral kyphotic angle (VA) and regional kyphotic angle (RA) were collected preoperatively, postoperatively and at the final follow-up. Hardware failure was assessed on radiological images at the last follow-up. Results: There were 36 patients who met the inclusion criteria with a mean follow-up duration of 53 months. The mean correction loss of %AVB, VA and RA were 10.2%, 2.9° and 5.6°, respectively. There were 6 patients (16.7%) with hardware failure at the final follow-up. Conclusion: Short-segment posterior pedicle screw fixation with TIF using bone chip grafts does not completely prevent hardware failure and progressive kyphosis in the treatment of unstable thoracolumbar burst fractures.

[Imageology study of correlation loss and its related factors after short-segment pedicle screw reduction and fixation for lumbar fractures].

OBJECTIVE: To analyze the correction loss after posterior segmental fixation for lumbar spine fractures and explore the related image factors. METHODS: Posterior short-segment fixation was received in 48 patients with L2-L4 fractures. There were 32 males and 16 females, with ages of 23 to 60 (45.98±8.20) yeaes. The anterior vertebrae height (AVH), vertebral wedge angle (VWA) of the injured vertebra and local kyphosis angle (LKA) were measured before operation, 1 week after operation and the final follow-up. The loss of segmental discal angle (LoSDA), LKA(LoLKA), AVH(LoAVH) were calculated between 1 week postoperative and the last follow up. Preoperative load-sharing scores(LSS), TLICS scores, and adjacent intervertebral disc injuries (IDIs) were assessed. Then the correlation between the age, follow up time, LSS, TLICS, IDIs and the correction loss was analyzed. RESULTS: The average follow-up was 12 to 18 (16.13±5.39) months. LKA, AVH and VWA at 1 week postoperative and those at the final follow up, were significantly improved compared with those preoperative (P<0.05). In the final follow up, the average LKA(5.70±3.17)° and AVH(4.31±5.95)% correction loss were observed compared with those 1 week postoperative(P<0.05). Otherwise the lose of VWA was not obvious(P>0.05). Univariate analysis showed that the SDA (r=0.706, 0.579, 0.449) and LKA(r=0.715, 0.566, 0.502) correction loss were aggravated with the increase of LSS, TLICS and IDIs, and AVH (r=-0.325, -0.219) correction loss was aggravated with the increase of LSS and TLICS(P<0.05). Multivariate analysis showed that increased LSS scores were all risk factors for segmental disc angle (SDA) loss, LKA correction loss, and AVH correction loss (P<0.05). CONCLUSION: The angle of adjacent intervertebral discs and anterior height of injured vertebrae were lost statistically after posterior short-segment pedicle screw treatment for lumbar fractures, and multivariate analysis showed that all of them were correlated with load-sharing score.

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.

Imageology study of correlation loss and its related factors after short-segment pedicle screw reduction and fixation for lumbar fractures / 中国骨伤

OBJECTIVE@#To analyze the correction loss after posterior segmental fixation for lumbar spine fractures and explore the related image factors.@*METHODS@#Posterior short-segment fixation was received in 48 patients with L@*RESULTS@#The average follow-up was 12 to 18 (16.13±5.39) months. LKA, AVH and VWA at 1 week postoperative and those at the final follow up, were significantly improved compared with those preoperative (@*CONCLUSION@#The angle of adjacent intervertebral discs and anterior height of injured vertebrae were lost statistically after posterior short-segment pedicle screw treatment for lumbar fractures, and multivariate analysis showed that all of them were correlated with load-sharing score.

Short- versus long-segment posterior spinal fusion with vertebroplasty for osteoporotic vertebral collapse with neurological impairment in thoracolumbar spine: a multicenter study.

BACKGROUND: Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine. METHODS: We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated. RESULTS: No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group. CONCLUSION: Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.

Radiographic Measurements as a Predictor of Correction Loss in Conservative Treatment of Colles' Fracture.

Dorsal displaced distal radius fracture (Colles' fracture) is very common and could occur from fragility in middle-aged and elderly people. Many Colles' fractures are still treated conservatively in clinics without hospitalization. Internal fixation using a palmar locking plate has been the standard treatment, but some complications have been reported. The aim of this study was to analyze changes in radiographic parameters over time in patients with conservatively treated Colles' fractures, and to establish whether the type of fracture influenced these changes. Prospective data collected included patient characteristics and radiological findings. The study was conducted at two private clinics and included 60 patients (13 men and 47 women; mean age, 72.5 years old; range, 55 to 96 years old) with a Colles' fracture (types of injury: intramedullary [n = 15], anatomical [n = 39], extramedullary [n = 2], and unknown [n = 4]) who were treated conservatively with manipulation and cast immobilization. Conservative, non-surgical treatment with manipulation was performed first, then, cast immobilization continued for 4 weeks. Loss of correction between the time of reduction and the final observation was defined by the following radiographic measurements: palmar tilt, radial inclination, and ulnar variance. The average final follow up period was 4.6 months (1.5-12 months). Immediately after reduction, 11 intramedullary fractures, 42 anatomical fractures and 7 extramedullary fractures were confirmed. Correction loss according to ulnar variance was significantly greater (P = 0.012) during the final observation for patients with an intramedullary injury at reduction than that for patients with extramedullary and anatomical injuries at reduction. We found that the correction loss for ulnar variance from immediately after reduction until the final observation was significantly greater in the intramedullary group, suggesting that an alternative to conservative treatment may be beneficial for patients with intramedullary fractures.

Comparison of loss of correction between PSO and VCD technique in treating thoracolumbar kyphosis secondary to ankylosing spondylitis, a minimum 2 years follow-up.

BACKGROUND: Pedicle subtraction osteotomy (PSO) and vertebral column decancellation (VCD) are frequently used methods for correction of thoracolumbar kyphosis resulting from ankylosing spondylitis (AS). However, there are limited reports performed to evaluate the difference of loss of correction and the effectiveness of PSO and VCD techniques in patients with thoracolumbar kyphosis secondary to AS. OBJECTIVE: To retrospectively estimate the effectiveness of correction and loss of correction of PSO and VCD techniques in patients with thoracolumbar kyphosis secondary to AS. METHODS: We performed a retrospective review of 61 consecutive AS kyphosis patients undergoing PSO or VCD surgery from March 2012 to April 2015. The patients were divided into PSO group (n = 25) and VCD group (n = 36) according to the types of osteotomies. Measurement of the radiographic parameters was performed and the change was analyzed. RESULTS: Mean loss of correction in the global kyphosis was 2.31° in the PSO group and 2.29° in VCD group at the last follow-up, respectively, with no significant difference. Progressive junctional kyphosis occurred in both groups. VCD obtained a significantly larger correction than PSO while sharing a similar incidence of complications. No serious complications were observed in the two groups. CONCLUSION: The PSO osteotomy and VCD osteotomy are both safe and effective methods in treating thoracolumbar kyphosis secondary to AS. Mild loss of correction mainly occurred in the global kyphosis in both techniques with no significant difference.

The clinical relevance of the presence of bridging syndesmophytes on kyphosis correction and maintenance following pedicle subtraction osteotomy for thoracolumbar kyphotic deformity in ankylosing spondylitis: a comparative cohort study.

BACKGROUND: The presence of bridging syndesmophytes (BS) in spinal osteotomy region serves traditionally as one critical determinant for selection of osteotomy techniques. While nowadays the proportion of kyphotic ankylosing spondylitis (AS) patients receiving pedicle subtraction osteotomy (PSO) with yet mobile neighboring disc has seen a substantial increase. Literatures investigating the clinical relevance of the presence of BS on kyphosis correction and maintenance following PSO are scarce. METHODS: A total of 71 thoracolumbar kyphotic AS patients treated with single-level PSO at our hospital between September 2010 and August 2014 were retrospectively reviewed, 32 of whom were stratified into the BS group (BG). The operative corrections of multiple spino-pelvic sagittal parameters were assessed. Comparison of the contribution of adjacent disc wedging to total correction per PSO segment was made between the BS and non-BS groups (NBG). The correction loss were also evaluated and compared with a minimum 2-year follow-up. RESULTS: A significantly younger age (30.97 ± 8.28 vs. 40.31 ± 8.44 yrs., p < 0.001), smaller pelvic incidence (PI) (43.03 ± 10.60 vs. 49.36 ± 9.75°, p = 0.011), greater wedging index of osteotomized vertebra (1.17 ± 0.16 vs. 1.09 ± 0.08, p = 0.011) and larger local kyphosis (19.59 ± 10.84 vs. 13.56 ± 8.50°, p = 0.013) was observed in NBG preoperatively. Patients in BG and NBG accomplished comparable amount of kyphosis correction per PSO segment (40.22 ± 7.09 vs. 43.85 ± 8.71°, p = 0.062). However, the contribution of adjacent disc wedging to total correction per PSO was significantly larger in NBG [8.10 ± 6.19 (18.5%) vs. 1.09 ± 2.88° (2.7%), p < 0.001]. By ultimate follow-up, the global kyphosis (18.26 ± 10.97 vs. 21.51 ± 10.89°, p < 0.05) and thoracic kyphosis (37.95 ± 11.87 vs. 42.87 ± 11.56°, p < 0.05) deteriorated significantly in the NBG but not BG, so was further pelvic retroversion as represented by increased pelvic tilt (19.46 ± 8.13 vs. 23.44 ± 8.19°, p < 0.05) and decreased sacral slope (23.02 ± 9.12 vs. 18.62 ± 10.10°, p < 0.05). Loss of corrections concerning contribution of adjacent disc wedging was also larger in NBG (1.41 ± 3.27 vs. 0.22 ± 1.49°, p < 0.05). CONCLUSIONS: Our study might suggest that the evaluation and treatment methods of kyphotic AS patients needed to be fine-tuned with appropriate subgrouping by the presence of syndesmophytes with bamboo sign as they were potentially distinct groups with different PI, contributor of lordosing capability and prognosis that might require separate analysis.

Safety and Efficacy of Treatment for Scolios Is Secondary to Spinal Muscular Atrophy Fused to Lumbar 5 Level.

INTRODUCTION: Patients with spinal muscular atrophy (SMA) usually have progressive scoliosis. Although fusion of the sacrum or pelvis has been recommended for correcting pelvic obliquity (PO), the procedure is invasive. This study determined as to whether performing instrumentation to the fifth lumbar vertebra (L5) is safe and effective for scoliosis in patients with SMA. METHODS: Twelve patients with SMA underwent posterior spinal fusion and stopping instrumentation at the L5 level. We evaluated age at surgery, the duration of surgery, blood loss, complications, preoperative and postoperative Cobb angles, and PO. RESULTS: The mean age at surgery was 11.4 years; the mean duration of surgery was 319 minutes, and the mean blood loss was 1170 mL. The Cobb angle improved from 97.3° to 39.1° at 1 month postoperatively (correction rate, 60.9%) and to 42.3° at the final follow-up. PO was corrected from 27.8° to 13.1° at 1 month postoperatively (correction rate, 51.7%) and to 19.8° at the final follow-up. No complications were reported. All patients showed improvement in low back pain, with reduced difficulty while sitting. However, >10% correction loss of PO was observed in 6 patients with high preoperative PO. CONCLUSIONS: The correction rate of scoliosis in SMA patients with posterior spinal fusion and instrumentation to the L5 level was acceptable, and no complications occurred. Scoliosis associated with SMA was more rigid and severer than scoliosis associated with Duchenne muscular dystrophy. Correction rates of the Cobb angle and PO in SMA patients with instrumentation to L5 were similar to those in SMA patients with instrumentation to the sacrum or pelvis. Correction loss of PO was greater in patients with high preoperative PO than in those with low preoperative PO. Instrumentation and fusion to L5 for scoliosis in patients with SMA seems safe and effective, except in cases of high preoperative PO.

The Relationship between Superior Disc-Endplate Complex Injury and Correction Loss in Young Adult Patients with Thoracolumbar Stable Burst Fracture.

BACKGROUND: To determine the relationship between superior disc-endplate complex injury and correction loss after surgery in a group of young adult patients with a stable thoracolumbar burst fracture. METHODS: The study group was comprised of young adult patients who had undergone short-segment posterior fixation and bone grafting under the diagnosis of a stable thoracolumbar burst fracture from March 2008 to February 2014. Follow-up was available for more than 1 year. Before surgery, magnetic resonance imaging was performed to determine injury to the anterior longitudinal ligament, posterior longitudinal ligament, and superior and inferior intervertebral discs and endplates. Correction loss was evaluated by the Cobb angle, intervertebral disc height, upper intervertebral disc angle, vertebral wedge angle, and vertebral body height. RESULTS: No significant relation was noted between correction loss and an injury to the anterior longitudinal ligament, posterior longitudinal ligament, inferior intervertebral disc/endplate, and fracture site, whereas an injury to the superior endplate alone and superior disc-endplate complex showed a significant association. Specifically, a superior intervertebral disc-endplate complex injury showed statistically significant relation to postoperative changes in Cobb angle (p = 0.026) and vertebral wedge angle (p = 0.047). CONCLUSIONS: A superior intervertebral disc-endplate complex injury may have an influence on the prognosis after short-segment fixation in young adult patients with a stable thoracolumbar burst fracture.

Effect of higher implant density on curve correction in dystrophic thoracic scoliosis secondary to neurofibromatosis Type 1.

OBJECTIVE The aim of this study was to investigate how implant density affects radiographic results and clinical outcomes in patients with dystrophic scoliosis secondary to neurofibromatosis Type 1 (NF1). METHODS A total of 41 patients with dystrophic scoliosis secondary to NF1 who underwent 1-stage posterior correction between June 2011 and December 2013 were included. General information about patients was recorded, as were preoperative and postoperative scores from Scoliosis Research Society (SRS)-22 questionnaires. Pearson correlation analysis was used to analyze the associations among implant density, coronal Cobb angle correction rate and correction loss at last follow-up, change of sagittal curve, and apical vertebral translation. Patients were then divided into 2 groups: those with low-density and those with high-density implants. Independent-sample t-tests were used to compare demographic data, radiographic findings, and clinical outcomes before surgery and at last follow-up between the groups. RESULTS Significant correlations were found between the implant density and the coronal correction rate of the main curve (r = 0.505, p < 0.01) and the coronal correction loss at final follow-up (r = -0.379, p = 0.015). There was no significant correlation between implant density and change of sagittal profile (p = 0.662) or apical vertebral translation (p = 0.062). The SRS-22 scores improved in the appearance, activity, and mental health domains within both groups, but there was no difference between the groups in any of the SRS-22 domains at final follow-up (p > 0.05 for all). CONCLUSIONS Although no significant differences between the high- and low-density groups were found in any of the SRS-22 domains at final follow-up, higher implant density was correlated with superior coronal correction and less postoperative correction loss in patients with dystrophic NF1-associated scoliosis.

Temporary short-segment pedicle screw fixation for thoracolumbar burst fractures: comparative study with or without vertebroplasty.

BACKGROUND CONTEXT: Short-segment posterior spinal instrumentation for thoracolumbar burst fracture provides superior correction of kyphosis by an indirect reduction technique, but it has a high failure rate. PURPOSE: The purpose of the study we report here was to compare outcomes for temporary short-segment pedicle screw fixation with vertebroplasty and for such fixation without vertebroplasty. STUDY DESIGN: This is a prospective multicenter comparative study. PATIENT SAMPLE: We studied 62 consecutive patients with thoracolumbar burst fracture who underwent short-segment posterior instrumentation using ligamentotaxis with Schanz screws with or without vertebroplasty. OUTCOME MEASURES: Radiological parameters (Cobb angle on standing lateral radiographs) were used. METHODS: Implants were removed approximately 1 year after surgery. Neurologic function, kyphotic deformity, canal compromise, and fracture severity were evaluated prospectively. RESULTS: After surgery, all patients with neurologic deficit had improvement equivalent to at least one grade on the American Spinal Injury Association impairment scale and had fracture union. Kyphotic deformity was reduced significantly, and reduction of the vertebrae was maintained with and without vertebroplasty, regardless of load-sharing classification. Although no patient required additional anterior reconstruction, kyphotic change was observed at disc level mainly after implant removal with or without vertebroplasty. CONCLUSIONS: Temporary short-segment fixation yielded satisfactory results in the reduction and maintenance of fractured vertebrae with or without vertebroplasty. Kyphosis recurrence may be inevitable because adjacent discs can be injured during the original trauma.

The Relationship between Superior Disc-Endplate Complex Injury and Correction Loss in Young Adult Patients with Thoracolumbar Stable Burst Fracture

BACKGROUND: To determine the relationship between superior disc-endplate complex injury and correction loss after surgery in a group of young adult patients with a stable thoracolumbar burst fracture. METHODS: The study group was comprised of young adult patients who had undergone short-segment posterior fixation and bone grafting under the diagnosis of a stable thoracolumbar burst fracture from March 2008 to February 2014. Follow-up was available for more than 1 year. Before surgery, magnetic resonance imaging was performed to determine injury to the anterior longitudinal ligament, posterior longitudinal ligament, and superior and inferior intervertebral discs and endplates. Correction loss was evaluated by the Cobb angle, intervertebral disc height, upper intervertebral disc angle, vertebral wedge angle, and vertebral body height. RESULTS: No significant relation was noted between correction loss and an injury to the anterior longitudinal ligament, posterior longitudinal ligament, inferior intervertebral disc/endplate, and fracture site, whereas an injury to the superior endplate alone and superior disc-endplate complex showed a significant association. Specifically, a superior intervertebral disc-endplate complex injury showed statistically significant relation to postoperative changes in Cobb angle (p = 0.026) and vertebral wedge angle (p = 0.047). CONCLUSIONS: A superior intervertebral disc-endplate complex injury may have an influence on the prognosis after short-segment fixation in young adult patients with a stable thoracolumbar burst fracture.

The role of bone void fillers in medial opening wedge high tibial osteotomy: a systematic review.

PURPOSE: A variety of bone void filling materials and methods are available in opening medial wedge HTO (OWHTO). The pertinent question revolves around if and when bone void fillers are needed. The primary purpose of this study was to systematically review outcomes and complications after OWHTO with and without the use of bone void fillers. METHODS: The EMBASE, PubMed\MEDLINE, Cochrane Library and Google Scholar databases were searched to identify articles that reported OWHTO results using different bone void fillers until March 2016. Only articles reporting the exact bone void filler type, the opening gap size and the fixation method were included. The extracted data included the study design, demographic data, the radiological and clinical results and complication rates. Outcomes were analysed with regard to bone void filler type, and comparison was made between the groups (allograft, autograft, synthetic bone void filler and OWHTO without bone void filling). RESULTS: Twenty-two articles reporting the results of 1421 OWHTO met the inclusion criteria. In total, 647 osteotomies were completed with allogeneic graft as bone void filler, 367 with synthetic materials, 199 with autograft and 208 without any bone void filling material. The maximum opening gap size was similar in all groups with mean of 9.8 mm (range 4-17.5 mm). Locking plate fixation was used in 90 % of the osteotomies that were completed without bone void filler, while all allograft cases and more then 90 % of the autograft cases were done with non-locking systems. The highest rates of non-union (1.1 %) were seen in the synthetic group, compared to 0.5 % in the all the other groups. CONCLUSIONS: This systematic review showed no definitive advantages for OWHTO with any bone void filler in terms of union rates and loss of correction. Moreover, the use of autografts or allografts showed more favourable outcomes than synthetic bone substitutes. OWHTO with gaps smaller then 10 mm and rigid fixation might be successfully managed without bone grafting. However, when bone grafting is needed, autograft bone provides higher rates of clinical and radiographic union. The use of synthetic bone substitutes in OWHTO cannot be recommended. LEVEL OF EVIDENCE: III.