Instrumentation failure following pediatric spine deformity growth-sparing surgery using traditional growing rods or vertical expandable prosthetic titanium ribs.

BACKGROUND: Instrumentation failure (IF) is a major complication associated with growth-sparing surgery for pediatric spinal deformities; however, studies focusing on IF following each surgical procedure are lacking. We aimed to evaluate the incidence, timing, and rates of unplanned return to the operating room (UPROR) associated with IF following each surgical procedure in growth-sparing surgeries using traditional growing rods (TGRs) and vertical expandable prosthetic titanium ribs (VEPTRs). METHODS: We reviewed 1,139 surgical procedures documented in a Japanese multicenter database from 2015 to 2017. Of these, 544 TGR and 455 VEPTR procedures were included for evaluation on a per-surgery basis. IF was defined as the occurrence of an implant-related complication requiring revision surgery. RESULTS: The surgery-based incidences of IF requiring revision surgery in the TGR and VEPTR groups were 4.3% and 4.0%, respectively, with no significant intergroup difference. Remarkably, there was a negative correlation between IF incidence per surgical procedure and the number of lengthening surgeries in both groups. In addition, rod breakage in the TGR group and anchor-related complications in the VEPTR group tended to occur relatively early in the treatment course. The surgery-based rates of UPROR due to IF in the TGR and VEPTR groups were 2.0% and 1.5%, respectively, showing no statistically significant difference. CONCLUSIONS: We found that IF, such as anchor related-complications and rod breakage, occurs more frequently earlier in the course of lengthening surgeries. This finding may help in patient counseling and highlights the importance of close postoperative follow-up to detect IF and improve outcomes.

Prevalence and clinical outcomes of vitamin D deficiency among Japanese multiple myeloma patients: a single-center observational study.

PURPOSE: Vitamin D plays a crucial role in skeletal metabolism and holds significant importance in the pathophysiology of multiple myeloma (MM). This study aimed to determine the prevalence of vitamin D deficiency among Japanese MM patients and its correlation with clinical outcomes. METHODS: Serum 25-hydroxyvitamin D (25(OH)D) levels were assessed in 68 MM patients at a single institution in Japan, analyzing their association with clinical status, laboratory parameters including procollagen type 1 N-propeptide (P1NP) and tartrate-resistant acid phosphatase 5b (TRACP-5b), health-related quality of life (HR-QOL) scores, and overall survival. Additionally, patients with suboptimal 25(OH)D levels received cholecalciferol supplementation (1000 IU/day), and changes in laboratory parameters were monitored. RESULTS: The median 25(OH)D level was 22 ng/ml, with 32% and 51% of patients exhibiting vitamin D deficiency (< 20 ng/ml) and insufficiency (20-29 ng/ml), respectively. The 25(OH)D levels were unrelated to sex, age, MM stage, or bone lesions, but the vitamin D-deficient group showed a tendency towards lower HR-QOL scores. Among patients achieving complete remission, vitamin D supplementation increased P1NP, while TRACP-5b remained unchanged. Overall survivals from vitamin D measurement and from MM diagnosis were significantly worse in the vitamin D-deficient group compared to the vitamin D-insufficient/-sufficient group. CONCLUSION: The study identified a considerable number of Japanese MM patients with insufficient serum vitamin D levels, with one-third being deficient. Additionally, vitamin D deficiency predicted poor overall survival in Japanese MM patients. Further investigation is required to determine whether vitamin D supplementation can improve the frailty and survival of vitamin D-deficient MM patients.

Risk factors for celiac artery and superior mesenteric artery stenosis in preoperative lumbar and thoracolumbar spinal surgery patients.

BACKGROUND: Ischemic necrosis of the abdominal organs caused by compression of the celiac artery (CA) and superior mesenteric artery (SMA) by the median arcuate ligament (MAL) after correction surgery has been recognized as acute celiac artery compression syndrome (ACACS). Here, using contrast-enhanced computed tomographic (CT) images, we sought to determine the prevalence and degree of CA and SMA stenosis in spinal patients preoperatively, and the risk factors associated with the stenosis. METHODS: We retrospectively examined contrast-enhanced abdominal CT of 90 patients with preoperative lumbar degenerative disease, lumbar burst fracture, or adult spinal deformity. The trunks of the CA and SMA were detected using three-dimensional reconstructed CT. To investigate their degree of stenosis, we determined the ratio of the narrowest diameter of the stenotic segment to the distal normal lumen's diameter. Patients with a degree of stenosis ≥35% were defined as being in the group with stenosis and the remainder as in the group without. To determine the risk factors for stenosis of these arteries, the relationship between the stenosis and CA and SMA calcification or the median arcuate ligament (MAL) crossing the proximal portion of the celiac axis (MAL overlap) was also investigated. RESULTS: The average degree of stenosis of the CA trunk was 12.1% ± 13.9% and that for the SMA trunk was 8.5% ± 8.8%. There were 8 patients (8.9%) in the group with CA stenosis and 2 patients (2.2%) in the group with SMA stenosis. The number of patients in the group with CA stenosis was significantly greater than the number with MAL overlap or CA calcification (P < 0.05). DISCUSSION: The prevalence of CA or SMA stenosis was 11.2% of preoperative patients due to undergo thoracolumbar fusion surgery. Calcifications of the CA trunk and MAL overlap are risk factors for CA stenosis.

Utilization of an Occlusion Balloon Catheter during Stent-Graft Placement to Treat Postsurgical Visceral Arterial Hemorrhage.

The utility of occluding the bleeding artery using an occlusion balloon catheter during stent-graft placement for visceral artery bleeding was evaluated. Stent-graft placement for visceral artery bleeding was performed using a balloon catheter in 6 patients. All bleeding occurred after biliary or pancreatic surgery. Since 1 patient underwent the procedure twice, 7 procedures were assessed in total. Technical success, procedure-related adverse events, and 30-day mortality rates were evaluated. Technical success was defined as the placement of the stent-graft at the target site and the resolution of extravasation or pseudoaneurysm. In all procedures, stent-graft placement was successfully performed (technical success rate, 100%). Focal liver infarction occurred in 2 of 7 patients (29%), but did not require further treatment and was considered a minor adverse event. The 30-day mortality rate was 0%. In conclusion, the use of an occlusion balloon in the feeding artery facilitated successful stent-graft repair of hemorrhage from visceral arteries.

Carbon Dioxide Angiography for the Detection of Lower Gastrointestinal Arterial Bleeding Initially Occult to Angiography with Iodinated Contrast Media.

This study evaluated the utility of carbon dioxide (CO2) in angiography for the detection of lower gastrointestinal arterial bleeding initially occult to angiography with iodinated contrast media. Fourteen patients underwent CO2-enhanced angiography. In all patients, extravasation was identified by contrast-enhanced computed tomography but not by initial iodinated contrast-enhanced angiography. After iodinated contrast-enhanced angiography, CO2-enhanced angiography was performed from the same catheter position. The detection capability for extravasation on CO2-enhanced angiography was evaluated. CO2-enhanced angiography allowed for the visualization of extravasation and subsequent transcatheter arterial embolization in 11 of 14 (79%) cases, with extravasation seen during either CO2-enhanced angiography (n = 8) or subsequent repeat iodinated contrast-enhanced angiography immediately after negative CO2-enhanced angiography (n = 3). Conservative treatment was performed in the remaining 3 cases. In conclusion, CO2-enhanced angiography appears useful for identifying occult lower gastrointestinal bleeding.

Embolization for acute arterial bleeding: use of the triaxial system and N-butyl-2-cyanoacrylate.

PURPOSE: The aim of this study was to evaluate the usefulness of transcatheter arterial embolization (TAE) using the triaxial system with N-butyl-2-cyanoacrylate (NBCA) for acute arterial bleeding in comparison to TAE using the triaxial system with gelatin sponges (GS)　and/or coils. MATERIAL AND METHODS: Between October 2013 and November 2018, 95 patients with acute arterial bleeding underwent emergency TAE using the triaxial system. Six patients underwent multiple TAEs and thus, 104 TAEs using the triaxial system were performed. In 26 of the 104 cases, TAE were performed with NBCA (NBCA group), and in the remaining 78 cases, TAE were performed with GS and/or coils (control group). RESULTS: Hemorrhagic shock and coagulopathy more often occurred in the NBCA group. Procedure time was shorter in the NBCA group. The technical success rate was 100% in both groups (p > 0.99). The clinical success rate in the NBCA and control groups was 92% and 96%, respectively (p = 0.6). There was one minor complication (4%, 1/26) of liver dysfunction in a patient of the NBCA group, but no complication in the control group (p = 0.26). CONCLUSION: TAE using the triaxial system with NBCA may be useful for acute arterial bleeding, especially in patients with hemorrhagic shock and coagulopathy.

Efficacy of lateral lumbar interbody fusion combined with posterior spinal fusion compared with three-column osteotomy for adult spinal deformity with severe lumbar sagittal deformity.

PURPOSE: The clinical and radiological results of adult spinal deformity (ASD) patients with a severe lumbar sagittal deformity undergoing multilevel lateral lumbar interbody fusion (LLIF) + posterior spinal fusion (PSF) were compared to patients undergoing three-column osteotomy (3CO). METHODS: We defined severe lumbar sagittal deformity as fulcrum backward bending (FBB) pelvic incidence minus lumbar lordosis (PI-LL) ≧ 20 degrees. A total of twenty-five patients with an ASD were enrolled between 2013 and 2018. Fifteen patients were in the LLIF + PSF group, and ten patients were in the 3CO group. We evaluated patient demographics, clinical outcomes, and radiographic parameters such as the Cobb angle and spinopelvic parameters from standing X-ray films in each group. RESULTS: The LLIF + PSF group had a significantly shorter follow-up time than the 3CO group. Postoperatively, the LLIF + PSF group had significantly lower PI-LL and a shorter sagittal vertical axis than the 3CO group. Postoperative PI-LL changes in the LLIF + PSF group were significantly smaller than those in the 3CO group. There were no differences in other patient demographics, radiographic parameters, or clinical outcomes between the groups. CONCLUSION: Multilevel LLIF + PSF improved the PI-LL and SVA more than did 3CO for ASD patients with severe lumbar sagittal deformity. This indicated that the multilevel LLIF with open PSF can provide good clinical outcomes even in cases with severe lumbar sagittal deformity such as large FBB PI-LL in which 3CO techniques usually are needed.

What factor induces stress in patients with AIS under brace treatment? Analysis of a specific factor using exploratory factor analysis.

BACKGROUND: Stress from brace treatment in patients with adolescent idiopathic scoliosis (AIS) can deteriorate their quality of life. A Japanese version of the Bad Sobernheim Stress Questionnaire-Brace (JBSSQ-brace) was developed to assess the stress from brace treatment for Japanese patients with AIS. However, the specific factors causing stress under brace treatment have remained unknown. METHOD: We enrolled 69 consecutive Japanese patients with AIS. Stress from brace treatment was assessed by JBSSQ-brace and Scoliosis Research Society-22 (SRS-22) instruments. The correlations of JBSSQ-brace with SRS-22 score, patient demographics and Cobb angle were analyzed by Spearman's rank correlation. Exploratory factor analysis was used to determine the psychological factor causing stress from brace treatment. RESULTS: JBSSQ-brace score was correlated with total score of SRS-22, self-image and mental health domain, but not age, degree of curvature, or other domains of the SRS-22. Factor analysis detected one underlying factor, which was more related to Questions 4 or 5 with the factor loadings of 0.8 than Questions 1 or 6 with loadings of 0.65. CONCLUSION: Stress from brace treatment was not associated with age, spinal curve severity, pain, or satisfaction of treatment. Exploratory factor analysis suggested "anxious feeling about how we are perceived by others" induces the stress from brace treatment in Japanese patients with AIS.

Anchor type at upper instrumented vertebra and postoperative shoulder imbalance in patients with Lenke type 1 adolescent idiopathic scoliosis.

PURPOSE: To clarify the impact of anchor type at upper instrumented vertebra (UIV) on postoperative shoulder imbalance in patients with Lenke type 1 adolescent idiopathic scoliosis (AIS) who underwent posterior spinal fusion. METHODS: Subjects were 81 patients with Lenke type 1 AIS who underwent posterior spinal fusion between 2004 and 2013. Twenty-five patients agreed to participate in the study. We divided the patients into two groups: Hook group (15 patients with hooks at UIV who underwent surgery between 2004 and 2011) and PS group (ten patients with pedicle screws at UIV who underwent surgery between 2012 and 2013). To evaluate shoulder balance, first thoracic vertebra tilt angle (T1 tilt), clavicle angle (CA), and radiographic shoulder height (RSH) were measured. RESULTS: There were no significant differences in preoperative T1 tilt, CA, or RSH between the both groups. The postoperative 1-week, 2-year, and most recently observed T1 tilts were significantly smaller in the Hook group than in the PS group. There were no significant differences in postoperative 1-week, 2-year, and most recently observed CAs between the two groups. Although there were no significant differences in 1-week postoperative RSH between the groups, the 2-year postoperative RSH was significantly smaller in the Hook group than in the PS group. The most recently observed RSH tended to be smaller in the Hook group than in the PS group, but the difference was not significant. CONCLUSIONS: In the PS group, poor shoulder balance remained over the long term. The hooks at UIV adjusted postoperative shoulder balance.

Clinical application of intraoperative O-arm navigation in reverse shoulder arthroplasty.

BACKGROUND: Inaccurate fixation and positioning of the glenoid component using conventional techniques are problematic in reversed shoulder arthroplasty (RSA). Our objective was to investigate the accuracy of O-arm navigation of the glenoid component in RSA. METHODS: This retrospective case-control study comprised 2 groups of 25 patients who underwent reversed shoulder arthroplasty with or without intraoperative O-arm navigation. The intraoperative goal was to place the component neutrally in the glenoid in the axial plane and 10° inferiorly tilted in the scapular plane. Glenoid version angle and inclination were measured by computed tomography obtained preoperatively and a year postoperatively. Operative time, intraoperative bleeding, and the presence of postoperative complications were recorded. RESULTS: Compared with the ideal, the range of error for version was 7.3° (SD 3.6°) in the control group and 5.6° (SD 3.6°) in the navigated group (P = 0.278), and the range of error for inclination was 18.3° (SD 11.7°) in the control group and 4.9° (SD 3.8°) in the navigated group (P = 0.0004). The mean operative time was 164.6 (SD 21.2) min in the control group and 192.0 (SD 16.2) min in the navigated group (P = 0.001). The mean intraoperative bleeding was 201.0 (SD 37.0) mL in the control group and 185.3 (SD 35.6) mL in the navigated group (P = 0.300). There were no complications reported related to the intraoperative O-arm navigation. CONCLUSION: O-arm navigation may be a useful tool for the placement with inferior tilt of the glenoid procedure in reversed shoulder arthroplasty.

Patients majoring in a healthcare field after scoliosis surgery: Comparison with the national census in Japan.

BACKGROUND: Although scoliosis surgery early in life may affect the career choice of the patient in favor of a healthcare field, no study has analyzed this relationship. We investigated the career paths of patients after scoliosis surgery. METHODS: A total of 212 patients with scoliosis who underwent corrective surgery at 12-17 years of age were mailed a questionnaire, of whom 98 (mean age at survey: 21.0 ± 1.7, years) responded. Choice of study major was determined by the same questions used in the Japanese national census. RESULTS: Of the 98 patients, 35% chose a career in healthcare compared with 11% of the general population of the same age, based on the national census. Healthcare was the most popular career choice of patients, whereas it ranked fourth according to the national census. Furthermore, 87% of patients reported that their decision to pursue a healthcare-related career was affected by their own medical experiences. Among the healthcare-related occupations, nursing ranked first, accounting for 35% of all healthcare professions chosen by the patients. Compared with patients who chose a non-healthcare career, those choosing a healthcare career decided on their study major at a significantly lower age. CONCLUSIONS: One-third of patients with scoliosis who underwent spine surgery chose a career in a healthcare field. Furthermore, an earlier age at the time of making a career decision was a significant factor associated with choosing a healthcare career. These findings suggest that the patients' experiences in the hospital positively affected their future career paths.

Japanese adaptation of the Bad Sobernheim Stress Questionnaire-Brace for patients with adolescent idiopathic scoliosis.

BACKGROUND: Patients with adolescent idiopathic scoliosis (AIS) under brace treatment perceive stress, not only from scoliosis, but from wearing the brace itself. The Bad Sobernheim Stress Questionnaire-Brace (BSSQbrace) was developed to assess the level of psychological stress induced by brace treatment for AIS. However, a Japanese version of BSSQbrace had not yet been developed. METHODS: We developed a Japanese adaptation of the Bad Sobernheim Stress Questionnaire-Brace (JBSSQ-brace) through a guideline-based process to adapt assessment of the psychological effect of brace treatment for AIS in Japanese patients. We administered the JBSSQ-brace to 71 patients with AIS under brace treatment in our clinic. Internal consistency and reproducibility were analyzed using Cronbach's alpha and a test-retest method. RESULTS: We included 44 patients that responded adequately. JBSSQ-brace achieved excellent internal consistency (Cronbach's alpha = 0.84 for the first questionnaire, and 0.87 for the second) and substantial reproducibility (interclass correlation coefficient = 0.75). The average score for JBSSQ-brace was 16.5 and 16.8, and almost 40% of AIS patients felt a moderate-to-high stress from brace treatment. CONCLUSIONS: JBSSQ-brace is an effective instrument with which to evaluate the stress level from brace treatment in Japanese patients with AIS.

Accuracy of powered surgical instruments compared with manual instruments for pedicle screw insertion: Evaluation using o-arm-based navigation in scoliosis surgery.

BACKGROUND: Though powered surgical instruments for pedicle screw insertion combined with navigation have been developed to reduce time taken for spine surgery, clinical evidence demonstrating the safety and effectiveness of powered surgical instruments is limited. The goals of the present study were to compare the accuracy of powered instruments and manual instruments using O-arm-based navigation in surgery for scoliosis. METHODS: We retrospectively identified 60 consecutive patients with adolescent idiopathic scoliosis who underwent posterior corrective surgery using O-arm based navigation, collected from Jun 2013 to Feb 2015. Overall, 393 screws were tapped and inserted in 30 patients using manual instruments (group M) and 547 screws were tapped and inserted in 30 patients using powered instruments (group P). Postoperative computed tomography was used to assess screw accuracy using the established Neo classification (Grade 0, no perforation; Grade 1, perforation <2 mm, Grade 2: perforation ≥2 and <4 mm, Grade 3: perforation ≥4 mm). The time to position one screw, including registration, was calculated. RESULTS: In group M, 331 (84%) of the 393 pedicle screw placements were categorized as Grade 0, 49 (13%) were Grade 1, 13 (3.3%) were Grade 2, and 0 were Grade 3. In group P, 459 (84%) of the 547 pedicle screw placements were categorized as Grade 0, 75 (14%) were Grade 1, 13 (2.4%) were Grade 2, and 0 were Grade 3. We found no significant difference in the prevalence of Grade 2-3 perforations between groups. The time to insert one pedicle screw was 5.4 ± 1.4 min in group M, but significantly decreased to 3.4 ± 1.2 min in group P. CONCLUSIONS: Our results demonstrate that powered instruments using O-arm navigation insert pedicle screws as accurately as conventional manual instruments using O-arm navigation. The use of powered instruments requires less time in O-arm surgery for scoliosis.

Photon-counting detector CT with an ultra-low-dose contrast media to diagnose a renal pseudoaneurysm: A case report.

A 75-year-old male, weighing 71 kg, was admitted to our institution with anemia related to a subcapsular hematoma after accidental extraction of a nephrostomy catheter. While the patient exhibited the progression of chronic kidney disease, he was not yet on dialysis. His serum creatinine level increased to 6.8 mg/dL, with an estimated glomerular filtration rate of 7.4 mL/min/1.73 m2. Radiologists planned contrast-enhanced photon-counting detector CT (PCD-CT) with an ultra-low-dose contrast media to mitigate the impact on renal function. The contrast media dosage was set at 7.4 gI, which was 82.6% lower that used in the standard protocol for a male weighing 71 kg. Non-contrast-enhanced PCD-CT identified a low-density nodular area within the renal subcapsular hematoma. Contrast-enhanced PCD-CT revealed contrast enhancement in both the early and late phases corresponding to the nodular area. On virtual monoenergetic images, the renal pseudoaneurysm was most clearly delineated at 40 keV. Following the diagnosis of a pseudoaneurysm, transcatheter arterial coil embolization was performed. No subsequent progression of anemia or the deterioration of renal function was observed, showcasing the potential of ultra-low-dose contrast-enhanced PCD-CT for the detection of small vascular abnormalities while minimizing adverse effects on renal function.

Impact of Brace-Related Stress on Brace Compliance in Adolescent Idiopathic Scoliosis: A Single-Center Comparative Study Using Objective Compliance Measurement and Brace-Related Stress.

Introduction: This study aimed to investigate the brace compliance and clinical background of patients with adolescent idiopathic scoliosis (AIS) who demonstrate different degrees of psychological brace-related stress. Methods: Forty-five patients initiating brace treatment with a Cobb angle between 25° and 45° were included. Patients receiving brace treatment for AIS were administered a questionnaire for brace-related stress (i.e., the Japanese version of the Bad Sobernheim Stress Questionnaire-Brace [JBSSQ-brace]). Based on their scores, we allocated the patients into two stress groups: mild-stress (≥16 points) and below-moderate-stress (<16 points). We investigated the character of brace compliance and brace-related psychological stress in all patients and compared the demographics and brace compliance between both groups. Results: Forty-one of 45 patients completed the study. The mean JBSSQ-brace scores were 18.7±5.1, 19.1±5.2, and 18.7±5.0 points at the 1-month, 4-month, and 1-year follow-ups, respectively. There was no significant change in JBSSQ-brace scores over one year after the brace prescription (P=0.332). There was no difference in-brace compliance between seasons during the first month of brace prescription (P=0.252). Both groups' overall brace compliance was comparable (below-moderate: 17.1±7.1 h/day vs. mild: 20.4±3.0 h/day; P=0.078). The mild-stress group showed better compliance than the below-moderate-stress group on weekdays (below-moderate: 17.0±6.9 h/day vs. mild: 20.5±2.8 h/day; P=0.048) and at nighttime (below-moderate: 82.3%±27.0%/nighttime vs. mild: 93.8%±12.4%/nighttime; P=0.008). Conclusions: Overall, brace compliance was comparable among patients with different brace-related stress, but brace compliance during weekdays and nighttime was significantly better in the mild-stress group.

Real-world efficacy of DA-EPOCH-R/HD-MTX regimen in CD5-positive diffuse large B cell lymphoma: a single-institute analysis.

CD5-positive diffuse large B cell lymphoma (CD5+ DLBCL) is a high-risk lymphoma type. Recently, the PEARL5 (a Phase II trial of DA-EPOCH and Rituximab with HD-MTX therapy for newly diagnosed DLBCL with CD5 expression) study demonstrated the efficacy of the DA-EPOCH-R (cyclophosphamide, etoposide, doxorubicin, vincristine, prednisone, and rituximab)/HD-MTX (high-dose methotrexate) regimen for CD5+ DLBCL. In this report, we revealed the impact of the DA-EPOCH-R/HD-MTX regimen on the clinical course of CD5+ DLBCL in the real-world. We retrospectively compared CD5+ and CD5- DLBCL patients diagnosed from January 2017 to December 2020 and analyzed their clinicopathological characteristics, treatment, and prognosis. There was no difference in age, sex, clinical stage, and cell of origin; however, the CD5-positive group had higher lactate dehydrogenase levels and a worse performance status than the CD5-negative group (p=0.00121 and p=0.0378, respectively). International prognostic index (IPI) was worse in the CD5-positive group than in the CD5-negative group (p=0.0498), but NCCN-IPI (National Comprehensive Cancer Network-IPI) was no different between the two groups. The CD5-positive group was more frequently treated with the DA-EPOCH-R/HD-MTX regimen than the CD5-negative group (p =0.001857). Complete remission rate and 1-year overall survival did not differ between the CD5-positive and -negative groups (90.0% vs 81.4%, p=0.853; 81.8% vs 76.9%, p=0.433). We conclude that the DA-EPOCH-R/HD-MTX regimen is effective for CD5+ DLBCL in this single institute analysis.

Incidence and causes of instrument-related complications after primary definitive fusion for pediatric spine deformity.

OBJECTIVE: Various complications have been reported in the treatment of pediatric spinal deformities. Among these, instrument-related complications could be critical concerns and risks of reoperation. This study aimed to identify the incidence and causes of complications after primary definitive fusion for pediatric spine deformities. METHODS: The authors retrospectively collected data from 14 institutions about patients who underwent primary definitive fusion between 2015 and 2017. There were 1490 eligible patients (1184 female and 306 male), with a mean age of 13.9 years. The incidence, causes, and reoperation rates were analyzed according to 4 etiologies of pediatric spine deformity (congenital, neuromuscular, syndromic, idiopathic). The complications were also categorized as screw-, hook-, or rod-related complications, implant loosening or backout, and junctional problems. RESULTS: The incidence of overall instrument-related complications was 5.6% (84 cases). Regarding etiology, the incidence rates were 4.3% (idiopathic), 6.8% (syndromic), 7.9% (congenital), and 10.4% (neuromuscular) (p < 0.05). The most common causes were pedicle screw malposition (60.7%), followed by implant backout or loosening (15.4%), junctional problems (13.1%), rod breakage (4.8%), and other complications (6.0%). Univariate analysis showed that etiology, type of deformity (kyphosis), surgical procedure, operation time, and estimated blood loss were significant factors. Multivariate analysis revealed that etiology (neuromuscular), surgical procedure (combined approach), and operation time (> 5 hours) remained as significant risk factors. Among all patients with instrument-related complications, 45% (38/84) required revision surgery. Of these cases, > 50% were related to pedicle screw malposition. Medial breach was the most common complication regardless of location, from upper thoracic to lumbar spine. CONCLUSIONS: Pedicle screw malposition was the primary cause of overall complications and subsequent reoperation. In addition to more precise screw insertion techniques, meticulous confirmation of pedicle screw placement, especially of medial breach, may reduce the overall instrument-related complications and revision rates.

Large Lumbar Lordosis Is a Risk Factor for Lumbar Spondylolysis in Patients with Adolescent Idiopathic Scoliosis.

STUDY DESIGN: A retrospective, single-center, observational study. OBJECTIVE: The aim of this study was to determine the prevalence and the characteristics of adolescent idiopathic scoliosis (AIS) patients with concomitant lumbar spondylolysis. SUMMARY OF BACKGROUND DATA: The prevalence and features of lumbar spondylolysis in patients with AIS are unclear. METHODS: We included 357 patients with AIS who underwent correction and fusion surgery. Preoperative computed tomography (CT) images were used to assess the existence of lumbar spondylolysis. Cobb angles of the curves, parameters of spinal alignment, Lenke classification, and the presence of low back pain were compared between patients with and without spondylolysis. RESULTS: Of the patients included in the study, 6.1% had lumbar spondylolysis. They had significantly greater lumbar lordosis (LL) and sacral slope (SS) than those without lumbar spondylolysis. Logistic regression analyses and receiver-operating characteristic curves showed that LL was a significant risk factor (odds ratio: 1.059; 95% confidence interval: 1.018-1.103; P = 0.005) of associating lumbar spondylolysis with a cut off value of 56.5 degrees (area under the curve [AUC]: 0.689; sensitivity = 63.6%, specificity = 71.0%). CONCLUSION: We should be vigilant for lumbar spondylolysis in AIS patients whose LL and SS are large, especially with LL larger than 56.5°.Level of Evidence: 3.