Correlation of radiographic parameters and patient satisfaction in adolescent idiopathic scoliosis treated with posterior screw-dual-rod instrumentation.

PURPOSE: In surgical treatment of adolescent idiopathic scoliosis (AIS), only a few studies measure both, radiological parameters and PROMs and correlate them. METHODS: Prospectively collected AIS-data of one scoliosis-center within a multicenter German-Spine-Society-Study. All patients underwent instrumented posterior spinal correction and fusion with pedicle-screw-dual-rod-systems from 05/2019 to 01/2021. The data were retrospectively analyzed. INCLUSION CRITERIA: age 11-17 years, follow-up (FU) at least 12 months. Clinical data, radiographic parameters, and PROMs (SRS-30-questionnaire) were collected. 100% of patients had X-ray images, 88.2% completed SRS-30. Parameters were given as mean ± SD. Differences and subdivision by lower instrumented vertebra (LIV) were analyzed by students t-test (significancy a = 0.05), associations by Pearson's correlation. RESULT: Total of 51 patients: 15 ± 1.4 years, BMI 20.7 ± 3.7 kg/m2, FU 16.6 ± 6.1 months, fusion length 9.2 ± 2.3 segments, implant density 93 ± 9%, surgical time 215 ± 71 min, mean blood loss 504 ± 360 ml. Mean preoperative Cobb angle of main curve 64 ± 14°, of secondary main curve 46 ± 12°, corrected by 68 ± 11%, 56 ± 17%, respectively. Mean thoracic rib and lumbar hump significantly decreased by - 8.5 ± 7.0° and - 7.7 ± 8.9° (p < 0.5). High thoracic rib hump almost unchanged, - 0.4 ± 2.8° (p = 0.3). Thoracic kyphosis (- 0.9 ± 12.8°, p = 0.6), lumbar lordosis (1.5 ± 10.1°, p = 0.3), clavicle angle (- 0.5 ± 2.7°) and spinopelvic parameters (p > 0.5) did not significantly change, only LIV-tilt from 24.5 ± 6.7° to 6.5 ± 4.3° (p < 0.05). PROMs significantly improved (p < 0.05), no significant improvement for function/activity (p = 0.4). Preoperative mean total-score was 3.6 ± 0.5, 4.2 ± 0.3 at FU(p < 0.05). Self-image improved in 67%. Moderately strong correlation for PROMs: the better LIV-tilt (r = - 0.5) correction and the shorter surgery time (r = - 0.4), the better SRS-30 total-score. No correlation for curve correction and patient's satisfaction. CONCLUSION: In summary, results of this study demonstrate good surgical correction and significant improvement of most PROMs.

Influence of posterior instrumented correction with pedicle screw dual rod systems on thoracic kyphosis in Lenke 1 and 2 curves: minimum 2 years follow-up.

PURPOSE: Adolescent idiopathic scoliosis (AIS) often correspond with hypo thoracic kyphosis (TK) or even lordosis. The aim of this study was to analyze the influence of posterior instrumentation in thoracic AIS. METHODS: Analysis of prospectively collected AIS-data with structural thoracic curves (Lenke type 1 & 2), operated 2010-2019 with pedicle screw dual rod systems in one scoliosis center. Follow-up (FU) minimum 24 months. Coronal and sagittal angles measured based on standing long-cassette-X-rays: thoracic major (MC), proximal thoracic (PC) and lumbar curve (LC), TK, lumbar lordosis (LL). STATISTICAL ANALYSIS: values as mean ± SD, differences by student's t-test (significancy a = 0.05), Pearson's correlation, sub-analysis with sagittal modifier (-, N, +). RESULTS: A total of 127 AIS could be identified (63% type 1, 37% type 2). Mean FU 32.2 ± 16.6 months, mean age 14 ± 1.5 years. Mean Correction of MC 73 ± 12%, PC 51 ± 17%, LC 69 ± 21% with a significantly better correction of PC in Lenke 2 curves(p < 0.05). On average, TK (FU-preop) decreased by -2.1 ± 12.1°(p < 0.05) in all AIS. Whereas TK in type 1 was unchanged (p = 0.9), TK significantly decreased by - 6.0 ± 12.7°(p < 0.05) in type 2. No significant difference in LL. TK in hypokyphotic cases increased by 9.5 ± 5.5°(p < 0.05), stayed almost unchanged (- 1.4 ± 9.1°,p = 0.2) in normokyphotic, decreased by - 17.2 ± 14.2°(p < 0.05) in hyperkyphotic cases. Only hypokyphotic cases had a moderately strong correlation between correction of LC (r = 0.6) and PC (r = - 0.4) (frontal plane) and change from pre- to postoperative TK (sagittal plane) (r = 0.6). No relevant correlations for normo- and hyperkyphotic AIS. Postoperative hypokyphosis was significantly more often in Lenke 2 (16.3% vs. 2.6%, p < 0.05). Rod diameter (5,5 mm versus 6 mm) had no significant influence. CONCLUSION: Significant correction of hypo- and hyperkyphosis can be achieved with posterior spinal fusion (pedicle screw dual rod systems), whereas normokyphotic spines stay unchanged. However, Lenke 2 curves have a significantly higher risk for a postoperative thoracic hypokyphosis.

[Increased risk of thoracic hypokyphosis after posterior spinal correction and fusion in adolescent idiopathic scoliosis with thoracic double curve]. / Erhöhtes Risiko der thorakalen Hypokyphose nach dorsaler Korrekturspondylodese bei adoleszenten idiopathischen Skoliosen mit thorakaler Doppelkrümmung.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is often associated with thoracic hypokyphosis or even lordosis. OBJECTIVES: To analyze the influence of posterior correction and fusion in thoracic, structurally double-curved AIS. MATERIAL AND METHODS: Out of 127 thoracic AIS (Lenke types 1 and 2) recorded prospectively, idiopathic double thoracic curve AIS were analyzed retrospectively. Surgery 2010-2019 with pedicle screw double rod systems in a scoliosis center. Follow-up (FU) at least 2 years. Frontal and sagittal angles (whole-spine radiographs, 2 planes): thoracic curve (MK), proximal-thoracic curve (PK) and lumbar curve (LK), thoracic kyphosis (TK), lumbar lordosis (LL). STATISTICAL ANALYSIS: values as MW ± SD, students t­test (significance a = 0.05), Pearson's correlation, sub-analysis with sagittal modifiers (-, N, +). RESULTS: A total of 47 AIS-double thoracic curve were identified, mean FU 29.3 ± 12.2 months, mean age 14 ± 1.5 years. The mean correction (FU-preop) of MK was 67%, PK 53%, LK 73%, each significant, (p < 0.05). On average, TK (FU-preop) decreased by -6.5 ± 11.6° (p < 0.05), no significant change from FU (p = 0.6). TK (FU-preop) increased by 8.6 ± 5.0° (p < 0.05) in hypokyphotic cases, significantly decreased by -4.8 ± 9.6° in normokyphotic AIS and -25.3 ± 11.1° in hyperkyphotic cases, respectively (p < 0.05). In hypokyphosis: moderately strong correlation between correction PK (r = -0.5) and spontaneous correction LK (r = 0.8) (frontal plane) and change from pre- to postop TK (sagittal plane) (p < 0.05). Moderate correlation for hyperkyphosis: correction PK (r = -0.5) and postop TK (p < 0.05). No relevant correlations for normokyphosis. 17% had postop hypokyphosis, of which 0% had preop hypokyphosis. Rod diameter (5.5 mm vs. 6 mm) had no significant effect on TC. CONCLUSIONS: Posterior instrumented correction and fusion (pedicle screw dual rod systems) can significantly correct both lateral curves in idiopathic double thoracic curves, although it is associated with an increased risk of postop thoracic hypokyphosis, especially in preoperatively normokyphotic patients.

Novel AI-Based Algorithm for the Automated Computation of Coronal Parameters in Adolescent Idiopathic Scoliosis Patients: A Validation Study on 100 Preoperative Full Spine X-Rays.

STUDY DESIGN: Retrospective, mono-centric cohort research study. OBJECTIVES: The purpose of this study is to validate a novel artificial intelligence (AI)-based algorithm against human-generated ground truth for radiographic parameters of adolescent idiopathic scoliosis (AIS). METHODS: An AI-algorithm was developed that is capable of detecting anatomical structures of interest (clavicles, cervical, thoracic, lumbar spine and sacrum) and calculate essential radiographic parameters in AP spine X-rays fully automatically. The evaluated parameters included T1-tilt, clavicle angle (CA), coronal balance (CB), lumbar modifier, and Cobb angles in the proximal thoracic (C-PT), thoracic, and thoracolumbar regions. Measurements from 2 experienced physicians on 100 preoperative AP full spine X-rays of AIS patients were used as ground truth and to evaluate inter-rater and intra-rater reliability. The agreement between human raters and AI was compared by means of single measure Intra-class Correlation Coefficients (ICC; absolute agreement; >.75 rated as excellent), mean error and additional statistical metrics. RESULTS: The comparison between human raters resulted in excellent ICC values for intra- (range: .97-1) and inter-rater (.85-.99) reliability. The algorithm was able to determine all parameters in 100% of images with excellent ICC values (.78-.98). Consistently with the human raters, ICC values were typically smallest for C-PT (eg, rater 1A vs AI: .78, mean error: 4.7°) and largest for CB (.96, -.5 mm) as well as CA (.98, .2°). CONCLUSIONS: The AI-algorithm shows excellent reliability and agreement with human raters for coronal parameters in preoperative full spine images. The reliability and speed offered by the AI-algorithm could contribute to the efficient analysis of large datasets (eg, registry studies) and measurements in clinical practice.

[What explains the "gendered reputation" of residency subjects? : Reasons for gendered specialty selection and careers in spine-surgery residency programs-compared to a "female" specialty]. / Wie erklärt sich der "geschlechtsspezifische Ruf" von Weiterbildungsfächern? : Gründe für die geschlechtsspezifische Fachauswahl und Karriere in Weiterbildungsfächern der Wirbelsäulenchirurgie sowie einem "weiblichen" Vergleichsfach.

BACKGROUND: Currently, the proportion of women in academic education and residency is predominant, but specialty-specific distribution of leading positions is partly reciprocal (orthopedics/surgery). Are there any differences that indicate a gender-dependent redistribution in leadership positions already in the selection of postgraduate training? METHODS: Online survey with orthopedics/trauma surgery (OUC) and neurosurgery (NCH) residents. Comparison with gynecology (GYN). Statistical analysis, mean in percent, statistical differences using t­ or chi2-test (significance level α = 0,05). RESULTS: Returned questionnaire = 277, complete participation = 250. Female residents: OUC:52%, NCH:57%, GYN:85%. A total of 49% were told in medical school that a subject was inappropriate for gender reasons (f57-76%, m10-33%). The most frequent reason for a subject: all = "operating activity". The second most frequent reason: OUC-f = "good working atmosphere", OUC-m = "establishment", NCH-f = "career" and "good working atmosphere", NCH-m = "good working atmosphere", GYN-f = "establishment", GYN-m = "career". The most frequent reason against: OUC/GYN = "hardly any possibility to become established", NCH = "negative leadership style by superiors". For female residents in OUC/NCH, work/family balance had the smallest influence on the choice of specialty. Their subjective evaluation of compatibility was significantly the worst, and overall OUC/NCH was significantly worse than GYN. Although female residents in NCH were more likely to justify the specialty choice based on career goals, male residents in OUC/NCH were more likely to aim for a higher hierarchical position. DISCUSSION: The results of this study emphasize that disciplines receive a gender-specific conditioning already at the undergraduate level, which has a clear impact on the choice of specialty. The image in this regard needs to be reconsidered, as even surgical subjects will predictably have to rely on more female specialists.

How can postoperative shoulder imbalance be prevented in adolescent idiopathic scoliosis type 2?

Postoperative shoulder imbalance (PSI) is a common complication following adolescent idiopathic scolio- sis (AIS) surgery. There is little data available in literature on prediction of PSI. Prospectively collected data of AIS with thoracic curve (Lenke 2), operated in 2014-2018 at a single scoliosis-center, were analyzed retrospectively using X-rays of whole spine and traction films (TA): age, Cobb-angle of proximal (PC), major thoracic (MC) and lumbar curve (LC), shoulder height [mm], clavicle angle [°], T1-tilt [°], plumb line [mm]. Results as mean ± standard deviation. Change over time (postOP- FU) compared using t-test (≥=0.05). Correlation of preOP parameters and curve correction with PSI (|≥|15mm) was analyzed by correlation (Pearson)- and regression-classification-analysis. 32 AIS, average age of 14±1.3 yrs. FU 16 months (84%). Curve correction was 52.5% (PC), 70.1% (MC), 69.9% (LC), significant change in FU for PC (-2.4°, p>0.05), not for MC, LC (p=0.2, p=0.6). Shoulder height was negative if right- side up: 2.9±15.1mm (preOP), 5.5±15.0 mm (TA), 17.9±14.9mm (postOP), 17.4±8.4mm (FU). 28% had preOP shoulder imbalance, 69% postOP and 44% FU had PSI. Shoulder height on TA correlated to change preOP to FU (r=0.62) and preOP shoulder height (r=-0.85), clavicle angle had strong correlation (r=- 0.81). Regression-classification-analysis: correction of MC>62.4%, 81.5% of cases had PSI; with correction of MC>64.9% and LC>93.2%, 51.9% of cases had PSI. PSI is a common in Lenke2 AIS. In preOP planning TA, shoulder position and clavicle angle should be considered to prevent PSI. Correction of MC should be moderate, overcorrection of the LC avoided.

Analysis of Preoperative and Operative Factors Influencing Postoperative Shoulder Imbalance in Lenke Type 1 Adolescent Idiopathic Scoliosis. / Analyse präoperativer und operativer Einflussfaktoren auf eine postoperative Schulterimbalance bei adoleszenter idiopathischer Skoliose Typ 1 nach Lenke.

BACKGROUND: Postoperative shoulder imbalance is a common complication in adolescent idiopathic scoliosis and may impair patient satisfaction. The little data in the literature on the prediction and treatment of postoperative shoulder imbalance is incongruous. According to some studies, postoperative shoulder imbalance depends on the superior instrumented vertebral bodies, skeletal maturity, extent of correction and flexibility of the major curve. QUESTION: Can preoperative radiological parameters from X-ray and traction films as well as correction of the curves be used to identify a factor impacting on postoperative shoulder imbalance? MATERIAL AND METHODS: Prospective data in adolescent idiopathic scoliosis with thoracic curve (Lenke type 1), operated on between 2015 and 2018 at a scoliosis centre, were analysed retrospectively based on full-length X-rays of the spine (pre-/postOP and follow-up (FU)) and preoperative-traction films: age; correction of proximal, main and lumbar curve; shoulder height [mm]; clavicle angle [°]; T1 tilt [°]; coronal plumb line deviation [mm]. The findings were expressed as means with standard deviation. Changes in parameters over time (postOP-FU) were compared by t test (significance level α = 0.05). The correlation between preOP parameters and extent of correction with postoperative shoulder imbalance (≥ 15 mm) was determined by Pearson correlation and regression classification analysis. OUTCOMES: 55 patients with adolescent idiopathic scoliosis, mean age of 15 ± 1.4 years. The FU-rate after a mean of 15 months was 80% (n = 44). Correction of proximal, main and lumbar curve: 47.0%, 75.8% and 68.8%, respectively, without statistically significant change (Δ) in FU (p > 0.05). Shoulder height was - 11.0 ± 12.7 mm (preOP), 15.5 ± 13.4 mm (postOP), 10.1 ± 10.6 mm (FU) (p < 0.05). 38% of those with adolescent idiopathic scoliosis had preOP right shoulder elevation; 55% (postOP) and 32% (FU) respectively had postoperative shoulder imbalance (left shoulder elevation). Strong statistical correlation was found for Δshoulder position (FU-preOP) with pre-OP shoulder position (r = - 0.7), and Δshoulder position (pre-OP traction films) (r = 0.5) with pre-OP clavicle angle (r = - 0.5). On regression classification analysis, 81.8% of cases did display postoperative shoulder imbalance if proximal curve correction was ≤ 64.4%; main and lumbar curve correction, Δshoulder elevation (preOP traction films) played a secondary role. DISCUSSION: One common complication even in Lenke type 1 adolescent idiopathic scoliosis is postoperative shoulder imbalance. Preoperative planning should include traction films, preoperative shoulder position and clavicle angle to avoid postoperative shoulder imbalance. Moderate correction of proximal curve is critical for postoperative shoulder balance.

Anterior Lumbar Interbody Fusion (ALIF) or Transforaminal Lumbar Interbody Fusion (TLIF) for Fusion Surgery in L5/S1 - What Is the Best Way to Restore a physiological Alignment?

STUDY DESIGN: A retrospective single center cohort study with prospective collected data from an institutional spine registry. OBJECTIVES: To determine whether restoration of lordosis L5/S1 is possible with both anterior lumbar interbody fusion (ALIF) and transforaminal lumbar interbody fusion (TLIF) and to find out which technique is superior to recreate lordosis in L5/S1. METHODS: Seventy-seven patients with ALIF and seventy-nine with TLIF L5/S1 were included. Operation time, estimated blood loss), and complications were evaluated. Segmental lordosis L5/S1 and L4/5, overall lordosis, and proximal lordosis (L1 to L4) were measured in X-rays before and after surgery. Oswesery disability index and EQ-5D were assessed before surgery, and 3 and 12 months after surgery. RESULTS: Mean operation time was 176.9 minutes for ALIF and 195.7 minutes for TLIF (p = 0.048). Estimated blood loss was 249.2 cc for ALIF and 362.9 cc for TLIF (p = 0.005). In terms of complications, only a difference in dural tears were found (TLIF 6, ALIF none; p = 0.014). Lordosis L5/S1 increased in the ALIF group (15.8 to 24.6°; p < 0.001), whereas no difference was noted in the TLIF group (18.4 to 19.4°; p = 0.360). Clinical results showed significant improvement in the Oswesery disability index (ALIF: 43 to 21.9, TLIF: 45.2 to 23.0) and EQ-5D (ALIF: 0.494 to 0.732, TLIF: 0.393 to 0.764) after 12 months in both groups, without differences between the groups. CONCLUSION: ALIF and TLIF are comparable methods for performing fusion at L5/S1, with good clinical outcomes and comparable rates of complications. However, there is only a limited potential for recreating lordosis at L5/S1 with a TLIF.

Preoperative lordosis in L4/5 predicts segmental lordosis correction achievable by transforaminal lumbar interbody fusion.

PURPOSE: The mean potential of lordosis restoration by transforaminal lumbar interbody fusion (TLIF) is supposed to be low in general. In contrast, clinical experience shows a wide range of segmental lordosis correction. In this study, the predictability of lordosis correction should be investigated. METHODS: Prospectively collected register data were analyzed retrospectively. One hundred twenty-one consecutive patients (2014-2016) operated with single-level TLIF L4/5 (10°-lordotic cage). Segmental lordosis (L4/5) and overall lordosis (L1-S1) were measured on lumbar X-rays: preoperatively (pre), after 3-5 days (post), at least 24 months postoperatively (2yFU). Outcome and satisfaction of patients were assessed. Parameters were statistically compared by students t-tests (a = 0.05). In addition, predictors of correction were analyzed. RESULTS: Age was 60.7 years, rate of 2yFU 41.3% (n = 50). Lordosis correction L4/5 was statistically significant with (post-pre) 4.9 ± 5.7° (p < 0.01), but not significant for L1-S1 (post-pre) 1.6 ± 8.0° (p = 0.3). A strong-moderate correlation of lordosis L4/5 (pre) and lordosis correction L4/5 (post-pre) was shown (r = - 0.6, p < 0,01). In a rising range of preoperative lordosis L4/5 from 15-30° the likelihood of lordosis loss increased. In 2yFU correction, L4/5 was significant with (post-pre) 5.4 ± 5.4° (p < 0.01), no significant long-term change (2yFU-postop) - 1.5 ± 4.9° (p = 0.2). No correlation (r = - 0.1) of correction and ODI. VAS-B improved by means of 2.9, VAS-L by 2.5, ODI by 19.1% (pre vs. 2yFU), each statistically significant (p < 0.01). CONCLUSION: Significant segmental relordosation can be performed by TLIF L4/5. The potential of correction strongly correlates with preoperative lordosis. Therefore, TLIF technique should be considered carefully in cases with a preoperative segmental lordosis of more than 15° and additional need of lordosation.

Intraoperative Radiation Exposure for Patients with Double-Curve Idiopathic Scoliosis in Freehand-Technique in Comparison to Fluoroscopic- and CT-Based Navigation. / Intraoperative Strahlenbelastung für Patienten mit doppelbogiger idiopathischer Skoliose in Freihandtechnik im Vergleich zu fluoroskopisch und CT-gestützter Navigation.

BACKGROUND: In the operative treatment of idiopathic scoliosis, posterior correction and fusion in freehand technique is a proven procedure and is frequently performed. Malpositioned pedicle screws can result in serious neurovascular complications. Intraoperative fluoroscopy and neurophysiological measurements are performed to ensure the correct position of pedicle screws. Newer procedures with fluoroscopic- and computertomographic-assisted navigation are advertised as less dangerous and with a more accurate screw position. HYPOTHESIS: Is the freehand technique used in the surgical treatment of idiopathic scoliosis safer than other methods with regard to complications caused by screw malposition and intraoperative radiation exposure? MATERIAL AND METHODS: Register data of 34 consecutive idiopathic scoliosis patients with two structural curves (Lenke 3 and 6) were collected prospectively in our scoliosis center and were retrospectively analyzed. The following parameters were evaluated: total radiation product, time of fluoroscopy, number of fused segments, time of operation, blood loss, screw-related complications and number of instrumented pedicle screws. All values were given as mean ± standard deviation and statistically analyzed. Finally, our data were compared on accuracy of screw placement and radiation exposure to data from literature with screw placement under navigation. RESULTS: Average age at the time of surgery was 23.6 ± 12 years. The average thoracic curve was 69.2 ± 14.2° preoperatively and 21.7 ± 12.8° postoperatively (correction 69.9%), the average lumbar curve was 64.3° ± 10.8° preoperatively and corrected to 15.6 ± 10.4° postoperatively (correction 76.2%). The total radiation product per patient was 145.7 ± 86.1 cGy*cm², the time of fluoroscopy 31.7 ± 23.5 s (11.5 segments), the time of operation 267.2 ± 64.1 min and the blood loss 700.4 ± 522.3 ml. A total of 803 pedicle screws were placed. No screw-associated complications were detected in the entire collective. The comparison of our data with freehand placement of pedicle screws to literature data showed a noticeable higher radiation exposure for the patient during fluoroscopic- and computertomographic-assisted navigation. DISCUSSION: The results showed that positioning of pedicle screws with freehand technique in patients with idiopathic scoliosis is accompanied with considerably lower intraoperative radiation exposure compared to fluoroscopic- or computertomographic-assisted navigation. An increased radiation exposure of these typically young patients is associated with an increased long-term risk for the occurrence of radiation-induced malignant diseases. With appropriate surgical experience, placement of pedicle screws in freehand technique is safe and effective and with similar accuracy than screws placed under navigation, but produces significantly less radiation exposure to the patients.

Intraoperative radiation exposure to patients in idiopathic scoliosis surgery with freehand insertion technique of pedicle screws and comparison to navigation techniques.

PURPOSE: In surgical correction of scoliosis with pedicle screw dual-rod systems, frequently used freehand technique of screw positioning is challenging due to 3D deformity. Screw malposition can be associated with serious complications. Image-guided technologies are already available to improve accuracy of screw positioning and decrease radiation to surgeon. This study was conducted to measure intraoperative radiation to patients in freehand technique, evaluate screw-related complications and compare radiation values to published studies using navigation techniques. METHODS: Retrospective analysis of prospectively collected data of 73 patients with idiopathic scoliosis, who underwent surgical correction with pedicle screw dual-rod system. Evaluated parameters were age, effective radiation dose (ED), fluoroscopy time, number of fused segments, correction and complications. Parameters were compared with regarding single thoracic curve (SC) and double thoracic and lumbar curves (DC), adolescent (10-18 years) or adult (> 18 years) idiopathic scoliosis, length of instrumentation. ED was compared with values for navigation from online database. RESULTS: Average age was 21.0 ± 9.7 years, ED was 0.17 ± 0.1 mSv, time of fluoroscopy was 24.1 ± 18.6 s, 9.5 ± 1.9 fused segments. Average correction for SC was 75.7%, for DC 69.9% (thoracic) and 76.2% (lumbar). No screw-related complications. ED was significantly lower for SC versus DC (p < 0.01), short versus long fusions (p < 0.01), no significant difference for age (p = 0.1). Published navigation data showed 6.5- to 8.8-times higher radiation exposure for patients compared to our results. CONCLUSION: Compared to navigation procedures, freehanded positioning of pedicle screws in experienced hands is a safe and effective method for surgical correction of idiopathic scoliosis with a significant decrease in radiation exposure to patients.

Perioperative complications after surgical treatment in degenerative adult de novo scoliosis.

BACKGROUND: Degenerative adult de novo (DAD) scoliosis appears characteristically in the sixth or seventh decade with symptoms of severe back pain and radiculopathy or spinal claudication. The aim of this study was to enhance the knowledge of perioperative complications and detect possible risk factors in this selective DAD scoliosis surgery. METHODS: This retrospective study included only patients with DAD scoliosis undergone correction spondylodesis with previous failure of conservative treatment. Excluded were patients with other types of scoliosis and previous fusion surgeries. Patient epidemiological data, medical comorbidities and treatments were included. Intraoperative data and perioperative complications were documented. Analyses regarding early, late and no complications were undertaken. RESULTS: A total of 92 patients with a mean age of 67.29 ± 7.93 years and clinical follow-up visits of minimum 12 months were included. On average, 5.26 ± 2.24 segments were fused. Early complications (e.g. wound healing defects, paresis, screw loosing) occurred in 23 patients and often required a re-operation. Cardiac arrhythmias, pacemaker and coumarin derivative therapies were associated with increased perioperative complications. The transforaminal lumbar interbody fusion technique was associated with early complications. Adjacent segment failure occurred in 36% and was the major late complication. Twenty patients did not have any complications in the minimum follow-up. CONCLUSIONS: This study analysed a selective DAD scoliosis collective and its' surgical treatment outcomes. It identified numerous perioperative complications (adjacent segment failure, postoperative paresis and epidural hematoma) and multiple possible predisposing risk factors (e.g. operative techniques and anti-coagulation therapies). This here gained information raises awareness in preoperative patient selection and preparation. Further studies in DAD scoliosis and a risk-adjusted patient selection/preparation are needed to improve treatment quality and outcomes.

[Extreme lateral interbody fusion. Indication, surgical technique, outcomes and specific complications]. / Die extrem laterale interkorporelle Fusion. Indikationen, Technik, Ergebnisse und Komplikationsmöglichkeiten.

BACKGROUND: Extreme lateral interbody fusion (XLIF) is an interbody fusion technique, in which access to the lateral part of the disc is achieved via a strong lateral transpsoatic approach. In general, the technique can be applied between T5 and L5. For lumbar segments, neuromonitoring is mandatory to protect the iliolumbar plexus during the psoas passage. OBJECTIVES: In this article, the results regarding use of the XLIF technique are summarized and compared with other anterior and anterolateral approaches. In addition, current publications regarding indication, technique, complications and clinical/radiological outcome measures are discussed. METHODS: The results of a literature review are presented and discussed. RESULTS: Regarding the indication and the surgical options for segmental restoration, the XLIF technique is comparable to anterior or anterolateral and open lateral interbody fusion. The minimally invasive XLIF access promises potentially lower morbidity than open procedures and the risk of injury of the iliac vessels is lower than in anterior and anterolateral approaches. CONCLUSION: Increasing numbers of spine surgeons are using the XLIF method. Current results indicate that XLIF is a safe and reproducible technique for deformities, adjacent level disease, and instability.

Two-year follow-up after decompressive surgery with and without implantation of an interspinous device for lumbar spinal stenosis: a prospective controlled study.

STUDY DESIGN: Two-arm prospective controlled study. OBJECTIVE: The aim of our study was to prospectively assess the outcome of symptomatic lumbar spinal stenosis (LSS) treated with decompressive surgery alone in comparison with additional implantation of the Coflex interspinous device. SUMMARY OF BACKROUND DATA: In symptomatic LSS, decompression surgery is an established treatment. Recently, a number of interspinous devices have been introduced as an alternative to conventional surgical procedures. The theoretical aim of the Coflex device is to unload the facet joints, restore foraminal height, and provide stability to improve the clinical outcome. Published information is limited, and there are no data that prove the superiority of the implant in comparison with traditional surgical approaches. METHODS: Sixty-two patients with symptomatic LSS were treated with decompressive surgery; 31 of these patients received an additional Coflex device. Preoperatively and postoperatively, disability and pain scores were measured using the Oswestry Disability Index, the Roland-Morris Disability Questionnaire, the Visual Analog Scale, and the pain-free walking distance. Patients underwent postoperative assessments at 3, 6, 12, and 24 month including the above-mentioned scores and patient satisfaction. RESULTS: There was a significant improvement (P<0.001) in the clinical outcome assessed in the Oswestry Disability Index, the Roland-Morris Disability Questionnaire, the Visual Analog Scale, and the pain-free walking distance at all times of reinvestigation compared with the base line in both groups. Up to 2 years after surgery, there were no significant differences between both groups in all ascertained parameters, including the patient satisfaction and subjective operation decision. CONCLUSIONS: The results of this first prospective controlled study indicate that the additional placement of a Coflex interspinous device does not improve the already good clinical outcome after decompressive surgery for LSS in the 24-month follow-up interval.

Spontaneous lumbar curve correction in selective anterior instrumentation and fusion of idiopathic thoracic scoliosis of Lenke type C.

BACKGROUND: Posterior pedicle screw instrumented correction and fusion have become the gold standard in the surgical treatment of thoracic scoliosis. However, in thoracic Lenke type C curves selective posterior fusion of the thoracic curve may lead to spinal imbalance. The aim of the study was to analyse the radiological results of selective anterior thoracic fusion using a standard open dual rod technique with special respect to spontaneous lumbar curve correction (SLCC). METHODS: Twenty-eight patients (26 patients with Lenke 1C and 2 patients with Lenke 2C curves) with an average age of 15 years were surgically treated with an anterior dual rod system through a standard open double thoracotomy approach. Average clinical and radiological follow-up was 4 years (24-84 months). RESULTS: Fusion was carried out mostly from end-to-end vertebra. The primary curve was corrected from 61.6° (average correction on reverse bending films 42.9 %) to 27.1° (56.0 % correction) with an average loss of correction of 2.2°. The secondary lumbar curve measured 47.7° preoperatively (40-56°, average correction on reverse bending films 66.2 %) and corrected spontaneously to 30.1° (36 % SLCC) and remained stable without any cases of deterioration or decompensation during follow-up. Lumbar apical vertebral translation increased minimally by an average of 4 mm directly, postoperatively, and returned to an average of preoperative values during follow-up. All but two curves remained as type C lumbar modifier at follow-up. Preoperatively, three patients showed a marked coronal imbalance of more than 3 cm (all left, average 4.0 cm); at follow-up, two patients were still out of balance by more than 3 cm (all to the left, average 3.4 cm). Preoperatively, a marked shoulder imbalance of more than 1.0 cm was found in 11 patients; this was corrected in all patients to <1.0 cm at follow-up. The apical vertebral rotation measured according to Perdriolle was corrected from 23.5° to 15.0° in the thoracic spine (36.2 % correction) with an average clinical reduction of the rib hump of 63.2 %. In the lumbar spine, there was no relevant radiological derotation; however, clinically, the lumbar hump corrected spontaneously by 44.3 %. Thoracic kyphosis measured 28.5° preoperatively and 32.3° at follow-up. All six patients with a preoperative hypokyphosis (<20°) of an average of 9.5° were successfully corrected to an average thoracic kyphosis of 23.8° at follow-up. There were no cases of junctional thoracolumbar kyphosis. There were neither reoperations nor implant failures with pseudarthrosis. CONCLUSION: Selective anterior correction and fusion in primary thoracic curves with lumbar modifier type Lenke C resulted in a reliable and satisfactory SLCC. Advantages of anterior versus posterior techniques are the true segmental derotation with excellent rib hump correction and a superior restoration of thoracic kyphosis.

Long-term follow-up after en bloc resection and reconstruction of a solitary paraganglioma metastasis in the first lumbar vertebral body: a case report.

INTRODUCTION: Paragangliomas are rare tumors that originate from the autonomic nervous system-associated paraganglia. They metastasize infrequently. Malignancy can only be demonstrated by the presence of chromaffin tissue at sites where it usually is not present, such as bone, lung or liver, or local recurrence after total resection of a primary mass. Paragangliomas within the central nervous system are usually intradural near the conus medullaris. The metastatic spread of a retroperitoneal paraganglioma to a vertebral body is extremely rare, and there are only a few cases reported in the literature. CASE PRESENTATION: We report the case of a 16-year-old Caucasian girl who had undergone resection of a retroperitoneal paraganglioma that measured 15 × 11.5 × 9.5 cm. After further staging, a solitary metastatic paraganglioma was detected in the first lumbar vertebral body. After initial chemotherapy, marginal en bloc resection and reconstruction were performed followed by radiotherapy. Histologic examination of the specimen revealed that the tumor cells did not show any response to preoperative chemotherapy, which is in line with a few other reports in the literature. Ten years after operative treatment, the patient is free of complaints, very satisfied with the result and without signs of local recurrence or distant metastases. CONCLUSION: We recommend en bloc spondylectomy and local radiotherapy in the treatment of solitary spinal metastatic paragangliomas.

[Modified primary stable ventral derotation spondylodesis with Halm-Zielke instrumentation for the treatment of idiopathic scoliosis]. / Die modifizierte primärstabile ventrale Derotationsspondylodese mit dem Halm-Zielke-Instrumentarium (HZI) zur Behandlung der idiopathischen Skoliose.

OBJECTIVE: Surgical technique with an anterior double-rod system for thoracic, thoracolumbar, or lumbar scoliosis. The aim of the system is to correct the coronal plane deformity and normalize the sagittal balance. INDICATIONS: Scoliosis which should have a coronal Cobb measurement of at least 40 degrees and should usually not exceed 90 degrees in between T4 and L4. In the Lenke classification, the curve types 1 (main thoracic) and curve type 5 (thoracolumbar/lumbar) are amenable to anterior instrumentation and fusion. CONTRAINDICATIONS: Osteoporosis. Infection. Allergic reaction to implants. Minor curves that do not correct to < 25 degrees on flexibility maneuvers. Structured kyphosis in the major curve. Severe sagittal plane malalignment with pathologic kyphosis cranial or caudal of the instrumented segments. SURGICAL TECHNIQUE: The spine is exposed via an open thoracotomy or a thoracoabdominal approach. After completion of diskectomies at each level, the anterior double-rod system is fixed with two bicortical screws per vertebral body. The longitudinal components consist of a solid rod and a threaded rod. The rods are contoured to maintain normal sagittal and coronal contour. The proximal screws are engaged first and then a cantilever force is used to correct the deformity. Occasionally, a partial rod rotation maneuver or intersegmental compression is performed. Morselized autograft (typically rib) is placed in the disk spaces. Intraoperative radiographs are taken to evaluate the correction. POSTOPERATIVE MANAGEMENT: Brace-free mobilization. Physiotherapy. Respiratory therapy. RESULTS: Very high rate of successful spondylodesis. Excellent frontal correction of about 60-70%. Very good spontaneous correction of adjacent minor curves of around 40%. Restoration of a physiological profile. Correction angle and length of fusion comparable to modern transpedicular double-rod systems.