Distal junctional kyphosis in patients with Scheuermann’s disease: a retrospective radiographic analysis

Purpose To investigate the relationship between preoperative and postoperative spinopelvic alignment and occurrence of DJK/DJF. Study design/setting This was a retrospective observational cohort study. Patient sample The sample included 40 patients who underwent posterior correction of SK from January 2006 to December 2014. Outcome measures Correlation analysis between the preoperative and postoperative spinopelvic alignment parameters and development of DJK over the course of the study period were studied. Methods Whole spine X-rays obtained before surgery, 3 months after surgery and at the latest follow-up were analyzed. The following parameters were measured: maximum of thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lower instrumented vertebra (LIV) and LIV plumb line. Development of DJK was considered as the primary end point of the study. The patient population was split into a control and DJK group, with 34 patients and 6 patients, respectively. Statistic analysis was performed using unpaired t test for normal contribution and Mann–Whitney test for skew distributed values. The significance level was set to 0.05. Results DJK occurred in 15% (n = 6) over the study period. There was a significantly lower postoperative TK for the group with DJK (42.4 ± 5.3 vs 49.8 ± 6.7, p = 0.015). LIV plumb line showed higher negative values in the DJK group (−43.6 ± 25.1 vs −2.2 ± 17.8, p = 0.0435). Furthermore, postoperative LL changes were lower for the DJK group (33.84 ± 13.86% vs 31.77 ± 14.05, p < 0.0001.) The age of the patients who developed DJK was also significantly lower than that of the control group (16.8 ± 1.7 vs 19.6 ± 4.9, p = 0.0024.) Conclusions SK patients who developed DJK appeared to have a significantly higher degree of TK correction and more negative LIV plumb line. In addition, there may be a higher risk for DJK in patients undergoing corrective surgery at a younger age

Harvesting local cylinder autograft from adjacent vertebral body for anterior lumbar interbody fusion: surgical technique, operative feasibility and preliminary clinical results

Autogenous iliac crest has long served as the gold standard for anterior lumbar arthrodesis although added morbidity results from the bone graft harvest. Therefore, femoral ring allograft, or cages, have been used to decrease the morbidity of iliac crest bone harvesting. More recently, an experimental study in the animal showed that harvesting local bone from the anterior vertebral body and replacing the void by a radio-opaque β-tricalcium phosphate plug was a valid concept. However, such a concept precludes theoretically the use of posterior pedicle screw fixation. At one institution a consecutive series of 21 patients underwent single- or multiple-level circumferential lumbar fusion with anterior cages and posterior pedicle screws. All cages were filled with cancellous bone harvested from the adjacent vertebral body, and the vertebral body defect was filled with a β-tricalcium phosphate plug. The indications for surgery were failed conservative treatment of a lumbar degenerative disc disease or spondylolisthesis. The purpose of this study, therefore, was to report on the surgical technique, operative feasibility, safety, benefits, and drawbacks of this technique with our primary clinical experience. An independent researcher reviewed all data that had been collected prospectively from the onset of the study. The average age of the patients was 39.9 (26–57) years. Bone grafts were successfully harvested from 28 vertebral bodies in all but one patient whose anterior procedure was aborted due to difficulty in freeing the left common iliac vein. This case was converted to a transforaminal interbody fusion (TLIF). There was no major vascular injury. Blood loss of the anterior procedure averaged 250 ml (50–350 ml). One tricalcium phosphate bone plug was broken during its insertion, and one endplate was broken because of wrong surgical technique, which did not affect the final outcome. One patient had a right lumbar plexopathy that was not related to this special technique. There was no retrograde ejaculation, infection or pseudoarthrosis. One patient experienced a deep venous thrombosis. At the last follow up (mean 28 months) all patients had a solid lumbar spine fusion. At the 6-month follow up, the pain as assessed on the visual analog scale (VAS) decreased from 6.9 to 4.5 (33% decrease), and the Oswestry disability index (ODI) reduced from 48.0 to 31.7 with a 34% reduction. However, at 2 years follow up there was a trend for increase in the ODI (35) and VAS (5). The data in this study suggest that harvesting a cylinder of autograft from the adjacent vertebral body is safe and efficient. Filling of the void defect with a β-tricalcium phosphate plug does not preclude the use of posterior pedicle screw stabilization

Cervical myelopathy caused by soft-tissue mass in diffuse idiopathic skeletal hyperostosis

A rare case of cervical spinal cord compression in diffuse idiopathic skeletal hyperostosis (DISH or Forestier’s Disease) caused by a craniocervical mass of soft-tissue is reported. The objective is to describe an uncommon mechanism of spinal cord compression in DISH. Three weeks after a cardiac infarction a 69-year-old man slowly developed spastic tetraparesis. Magnetic resonance tomography showed a craniocervical tumor compressing the spinal cord and a massive DISH of the cervical spine. An extended mass of yellowish amorphous material was removed from between the dura, the posterior odontoid process and the posterior aspect of vertebral body C2 reaching to the upper part of C3.The histologic appearance indicated connective tissue and cell-degenerated cartilaginous tissue. There was no inflammatory component and no evidence of neoplasia. No ossification of the posterior longitudinal ligament (OPLL) was found. After removal and craniocervical stabilization the patient’s neurologic function improved remarkably. The increase of mechanical stress on the atlantoaxial segment and enhanced proliferation reaction of the connective tissue in DISH are suggested as the underlying pathomechanisms in the formation of this soft-tissue mass

Posterior fusion only for thoracic adolescent idiopathic scoliosis of more than 80°: pedicle screws versus hybrid instrumentation

The treatment of thoracic adolescent idiopathic scoliosis (AIS) of more than 80° traditionally consisted of a combined procedure, an anterior release performed through an open thoracotomy followed by a posterior fusion. Recently, some studies have reassessed the role of posterior fusion only as treatment for severe thoracic AIS; the correction rate of the thoracic curves was comparable to most series of combined anterior and posterior surgery, with shorter surgery time and without the negative effect on pulmonary function of anterior transthoracic exposure. Compared with other studies published so far on the use of posterior fusion alone for severe thoracic AIS, the present study examines a larger group of patients (52 cases) reviewed at a longer follow-up (average 6.7 years, range 4.5–8.5 years). The aim of the study was to evaluate the clinical and radiographic outcome of surgical treatment for severe thoracic (>80°) AIS treated with posterior spinal fusion alone, and compare comprehensively the results of posterior fusion with a hybrid construct (proximal hooks and distal pedicle screws) versus a pedicle screw instrumentation. All patients (n = 52) with main thoracic AIS curves greater than 80° (Lenke type 1, 2, 3, and 4), surgically treated between 1996 and 2000 at one institution, by posterior spinal fusion either with hybrid instrumentation (PSF–H group; n = 27 patients), or with pedicle screw-only construct (PSF–S group; n = 25 patients) were reviewed. There were no differences between the two groups in terms of age, Risser’s sign, Cobb preoperative main thoracic (MT) curve magnitude (PSF–H: 92° vs. PSF–S: 88°), or flexibility on bending films (PSF–H: 27% vs. PSF–S: 25%). Statistical analysis was performed using the t test (paired and unpaired), Wilcoxon test for non-parametric paired analysis, and the Mann–Whitney test for non-parametric unpaired analysis. At the last follow-up, the PSF–S group, when compared to the PSF–H group had a final MT correction rate of 52.4 versus 44.52% (P = 0.001), with a loss of −1.9° versus −11.3° (P = 0.0005), a TL/L correction of 50 versus 43% (ns), a greater correction of the lowest instrumented vertebra translation (−1.00 vs. −0.54 cm; P = 0.04), and tilt (−19° vs. −10°; P = 0.005) on the coronal plane. There were no statistically significant differences in sagittal and global coronal alignment between the two groups (C7-S1 offset: PSF–H = 0.5 cm vs. PSF–S = 0 cm). In the hybrid series (27 patients) surgery-related complications necessitated three revision surgeries, whereas in the screw group (25 patients) one revision surgery was performed. No neurological complications or deep wound infection occurred in this series. In conclusion, posterior spinal fusion for severe thoracic AIS with pedicle screws only, when compared to hybrid construct, allowed a greater coronal correction of both main thoracic and secondary lumbar curves, less loss of the postoperative correction achieved, and fewer revision surgeries. Posterior-only fusion with pedicle screws enabled a good and stable correction of severe scoliosis. However, severe curves may be amenable to hybrid instrumentation that produced analogous results to the screws-only constructs concerning patient satisfaction; at the latest follow-up, SRS-30 and SF-36 scores did not show any statistical differences between the two groups