Clinical effectiveness of Enneking appropriate versus Enneking inappropriate procedure in patients with primary osteosarcoma of the spine: a systematic review with meta-analysis Abstract Purpose Primary osteosarcoma of the spine is a rare osseous tumour. En bloc resection, in contrast to intralesional resection, is the only procedure able to provide Enneking appropriate (EA) margins, which has improved local control and survival of patients with primary osteosarcoma of the spine. The objective of this study is to compare the risk of local recurrence, metastases development and survival in patients with primary osteosarcoma of the spine submitted to Enneking appropriate (EA) and Enneking inappropriate (EI) procedures. Methods A systematic search was performed on EBSCO, PubMed and Web of Science, between 1966 and 2018, to identify studies evaluating patients submitted to resection of primary osteosarcoma of the spine. Two reviewers independently assessed all reports. The outcomes were local recurrence, metastases development and survival at 12, 24 and 60 months. Results Five studies (108 patients) were included for systematic review. These studies support the conclusion that EA procedure has a lower local recurrence rate (RR 0.33, 95% CI 0.17–0.66), a lower metastases development rate (RR 0.39, 95% CI 0.17–0.89) and a higher survival rate at 24 months (RR 1.78, 95% CI 1.24–2.55) and 60 months (RR 1.97, 95% CI 1.14–3.42) of follow-up; however, at 12 months, there is a non-significant difference. Conclusions EA procedure increases the ratio of remission and survival after 24 months of follow-up. Multidisciplinary oncologic groups should weigh the morbidity of an en bloc resection, knowing that in the first year the probability of survival is the same for EA and EI procedures. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Characterization of the microstructure of the intervertebral disc in patients with chronic low back pain by diffusion kurtosis imaging Abstract Purpose Multivariate analysis of T2-weighted signal, diffusion ADC, and DKI parameters and tractography were used to differentiate chronic non-specific low back pain (CLBP) patients and asymptomatic controls (AC). Methods A total of 30 patients with CLBP and 23 AC underwent diffusion kurtosis imaging (DKI) of lumbar spine with a 3T MRI scanner to get the ADC values and seven parameters of DKI in the nucleus pulposus (NP) of the intervertebral disc. The tractography and the tract-related parameters as other parameters were also generated to indicate the intactness of annulus fibrosus (AF). T2-grades of the discs were also quantified based on an eight-grade degeneration grading system. ADC and T2-grades were compared with DKI parameters for the differentiation of CLBP and AC groups. Results There was no difference in the T2 grades, ADC value, and multiple parameters in DKI of NP between CLBP and AC groups (P > 0.05). The average FA values in NP in AC group were found significantly higher than in the CLBP group (P < 0.05). The scores for the intactness of AF of the intervertebral discs were significantly different in CLBP and AC groups, with 90% of sensitivity and 70% specificity (P < 0.05). Additionally, there were significantly differences in the length and volume values of the AF in CLBP and AC groups (P < 0.05). Conclusion DKI is a good noninvasive method, and it might help to differentiate CLBP from AC. Particularly, the continuation of DKI tractography reflects the presence of annulus fibrosus fissures, an important character in the generation of the low back pain. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Advancing spinal fellowship training: an international multi-centre educational perspective Abstract Purpose The purpose of this article is to review the importance of contemporary spine surgery fellowships and educational strategies to assist with fellowship design and delivery. Methods Spine surgery fellowship includes trainees from orthopaedic and neurosurgical backgrounds and is increasingly indicated for individuals wishing to pursue spine surgery as a career, recognizing how spinal surgery evolved significantly in scope and complexity. We combine expert opinion with a review of the literature and international experience to expound spine fellowship training. Results Contemporary learning techniques include boot camps at the start of fellowship which may reinforce previous clinical learning and help prepare fellows for their new clinical roles. There is good evidence that surgical specialty training boot camps improve clinical skills, knowledge and trainee confidence prior to embarking upon new clinical roles with increasing levels of responsibility. Furthermore, as simulation techniques and technologies take on an increasing role in medical and surgical training, we found evidence that trainees’ operative skills and knowledge can improve with simulated operations, even if just carried out briefly. Finally, we found evidence to suggest a role for establishing competence-based objectives for training in specific operative and technical procedures. Competence-based objectives are helpful for trainees and trainers to highlight gaps in a trainee’s skill set that may then be addressed during training. Conclusions Spinal fellowships may benefit from certain contemporary strategies that assist design and delivery of training in a safe environment. Interpersonal factors that promote healthy teamwork may contribute to an environment conducive to learning. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Isolated multiple lumbar transverse process fractures with spinal instability: an uncommon yet serious association Abstract Purpose Isolated vertebral transverse process fractures of thoracolumbar spine without other vertebral injuries and neurological deficit are generally considered as minor injuries with no concern for associated spinal instability. This report describes a case of multiple lumbar transverse fractures associated with an unexpected yet clinically significant spinal instability. Methods A young male presented with right flank pain following being pushed and trapped against the ground by a reversing truck. The neurological examination was normal, and computed tomography (CT) imaging revealed multiple fractures at right transverse processes from L1 to L5, a single left-sided transverse process fracture at L2 and subtle facet joint distraction without other spinal lesions or visceral injuries. The injury was initially deemed as stable requiring symptomatic treatment and in-patient observation. However, discharge upright X-rays taken in a brace showed marked subluxation of L2/L3 and L3/L4 levels. Results Magnetic resonance imaging revealed significant discoligamentous injuries involving anterior and posterior longitudinal ligaments, annulus fibrosus as well as posterior ligamentous complex. The patient underwent posterior spinal instrumentation and fusion of L1 to L5. Conclusions This is the first case description of association of multisegmental lumbar transverse process fractures with notoriously unstable injuries of the major soft-tissue stabilizers of the spine presenting subtle changes on CT images. When a seemingly benign spinal injury is caused by high-energy trauma, careful scrutiny for associated instability is needed. In this case, the standing in-brace X-ray was able to avoid a misdiagnosis and potentially unfavourable outcome.

The factors related to the poor ADL in the patients with osteoporotic vertebral fracture after instrumentation surgery Abstract Purpose Osteoporotic vertebral fracture (OVF) with nonunion or neurological deficit may be a candidate for surgical treatment. However, some patients do not show improvement as expected. Therefore, we conducted a nationwide multicenter study to determine the predictors for postoperative poor activity of daily living (ADL) in patients with OVF. Methods We retrospectively reviewed the case histories of 309 patients with OVF who underwent surgery. To determine the factors predicting postoperative poor ADL, uni- and multivariate statistical analyses were performed. Results The frequency of poor ADL at final follow-up period was 9.1%. In univariate analysis, preoperative neurological deficit (OR, 4.1; 95% CI, 1.8–10.3; P < 0.001), perioperative complication (OR, 3.4; P = 0.006), absence of preoperative bone-modifying agent (BMA) administration (OR, 2.7; P = 0.03), and absence of postoperative recombinant human parathyroid hormone (rPTH) administration (OR, 3.9; P = 0.006) were significantly associated. In multivariate analysis, preoperative neurological deficit (OR, 4.6; P < 0.001), perioperative complication (OR, 3.4; P = 0.01), and absence of postoperative rPTH administration (OR, 3.9; P = 0.02) showed statistical significance. Conclusions Preoperative neurological deficit, perioperative complication, and absence of postoperative rPTH administration were considered as predictors for postoperative poor ADL in patients with OVF. Neurological deficits and complications are often inevitable factors; therefore, rPTH is an important option for postoperative treatment for OVF. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Answer to the letter to the editor of Y. Li et al. concerning “Intraosseous basivertebral nerve ablation for the treatment of chronic low back pain: a prospective randomized double-blind sham-controlled multi-center study” by Fischgrund JS, et al. [Eur Spine J; (2018) 27(5): 1146–1156]

Extensor/flexor ratio of neck muscle strength and electromyographic activity of individuals with migraine: a cross-sectional study Abstract Purpose Neck pain is considered a common characteristic of migraine attacks. The relationship between neck pain and migraine can be explained by central sensitization of the trigeminocervical complex, where superior cervical afferents and the trigeminal nerve converge. However, few studies have evaluated motor control of cervical muscles in individuals with migraine. Thus, the purpose of the present study was to determine the extensor/flexor ratio of neck muscle strength and electromyographic activity during a test of maximal voluntary isometric contraction and craniocervical flexion in individuals with migraine and individuals without history of migraine or other headaches. Methods Fifty-two women with the disease and 52 women with neither a history of migraine nor neck pain, between 18 and 55 years old, were included in the study. The electromyographic activities of the sternocleidomastoid, anterior scalene, splenius capitis, and upper trapezius muscles were evaluated during a test of maximal voluntary isometric contraction and craniocervical flexion. Results The migraine group presented lower flexor muscle strength and a higher extensor/flexor muscle strength ratio than the control group. In addition, the migraine group showed a reduced electromyographic extensor/flexor muscle ratio during maximal voluntary isometric contraction in flexion. The results demonstrated worse performance in the craniocervical flexion test of the migraine group and a lower electromyographic ratio of extensor/flexor neck muscles in the last stage of the test. Conclusion Altogether, the migraine group presented an imbalance in cervical muscles verified not only during force production, but also during muscle activity. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Total disc replacement for lumbar degenerative disc disease: single centre 20 years experience Abstract Purpose To report clinical and radiographic outcomes, rate of complications and influence on spinal alignment on long-term follow-up (FU) of patients who underwent lumbar total disc arthroplasty (TDR), bringing some evidence to determine the profile of the most well-suited patients for TDR. Methods A retrospective review of patients underwent TDR for low back pain from degenerative disc disease (DDD) resistant to conservative treatment was performed. Demographic features, surgical data, clinical and radiographic outcomes, complications and spinopelvic parameters were evaluated. Results Thirty patients (32 TDR) were included with a mean FU of 164 ± 36.5 months. The clinical outcomes measured by visual analogue scale and Oswestry Disability Index showed a significant improvement between preoperative and 1-year FU (p < 0.01). No significant temporal variance has been identified between 1-year and long-term follow-up (p > 0.05). The surgical revision rate was 10%. The overall rate of complications was 20%. At final follow-up, the mobility of the prosthesis was preserved in 68.75% of the cases, and 73.3% of the patients were globally well aligned. Conclusion The optimal surgical indication is crucial to achieve excellent clinical and radiological outcomes. According to the literature and to our experience, we underline the importance of a coronal deformity < 15° Cobb angle and a Roussouly type 1 or 2 as the profile of the most well-suited patient for TDR. Our long-term results confirm the existing evidence about efficacy and safety of TDR as a reliable option, in optimal surgery indication, to treat DDD. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

Clinical photography in severe idiopathic scoliosis candidate for surgery: is it a useful tool to differentiate among Lenke patterns? Abstract Purpose Clinical photography has proven to be reliable for posture assessment in adolescents and young adults with idiopathic scoliosis. This paper attempts to elucidate whether clinical photography is capable of distinguishing the distinctive characteristics in trunk deformity of the different Lenke patterns in patients with severe scoliosis candidate for surgery. Methods One hundred and seventy-three patients (82% women), average age of 20.8 years and average largest curve magnitude of 58.7° were included. PA standing full-spine X-rays and digital photographs from the back of the trunk were measured. Radiological measurements It is used to measure magnitude of the proximal thoracic (PTC), main thoracic (MTC) and thoracolumbar/lumbar (TL/LC) curves, T1 tilt and the clavicle–rib intersection angle. Photographic measurements It is used to measure shoulder height angle, axilla height angle, waist height angle (WHA), right and left waist angles and trunk areas. Statistical analysis One-way ANOVA to test mean differences among Lenke types for radiological and photographic measurements was performed. ROC curve analysis was conducted to find out cutoff values in photographic measurements to differentiate among curve patterns. Results Most radiological and photographic measurements differ among curve patterns. On ROC curve analysis, solid cutoff values were found for WHA (AUC = 0.8), left waist angle (AUC = 0.81), right waist angle (AUC = 0.81) and the difference between left and right waist angles (AUC = 0.86) to differentiate between types 1 and 2 and the other three types (3, 5 and 6). Conclusions Clinical photography is a valid method for assessing trunk asymmetry in severe idiopathic scoliosis. Specifically, for waist area measurements, robust cutoff values can be determined to discriminate among different curve patterns according to Lenke classification. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.

A critical thoracic kyphosis is required to prevent sagittal plane deterioration in selective thoracic fusions in Lenke I and II AIS Abstract Purpose Thoracic hypokyphosis following AIS correction may be associated with reduced lumbar lordosis with potential adverse effects on the global sagittal balance. In the present study, we were interested in how the amount of thoracic kyphosis influences the sagittal profile and balance in selective thoracic (STF) and thoracolumbar fusions. Methods Out of 154 patients, 86 patients had correction of AIS Lenke I or II with a side-loading pedicle screw system and completed a 2-year follow-up. Patient factors such as age, Risser grade, lowest and upper instrumented vertebra, and lumbar modifier were recorded. Coronal Cobb and sagittal parameters were measured using Surgimap. Statistical analysis according to distributions and multiple linear and logistic regressions was performed using STATA for Mac v13. Results In STF, logistic regression against post-operative change in SVA versus thoracic kyphosis allowed calculation of a critical thoracic kyphosis of 23° (ROC AUC 0.65, spec 0.70, sens 0.63), below which deterioration of the sagittal vertical axis is more likely (PPV 71.4%). Patients with hypokyphosis exhibited an increase in the SVA (pre-operative 7.2 ± 37.1 mm vs. 23.1 ± 27.6 mm at 2 years, p = 0.0164), whereas it was maintained from pre-operative to 2 years post-operative if thoracic kyphosis is above 23° (pre-operative 2.5 ± 28.9 mm vs. 5.4 ± 26.9 mm at 2 years, p = 0.579). Conclusion A critical thoracic kyphosis of 23° and more should be aimed for in hypokyphotic patients to potentially avoid post-operative sagittal plane deterioration with mechanical and likely also clinical consequences. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.