Anterior column realignment via a minimally invasive hybrid approach in adult spinal deformity surgery: a short-term retrospective study.

BACKGROUND: Anterior column realignment (ACR) is a novel surgical method for correcting spinal sagittal balance. meanwhile, oblique lumbar interbody fusion (OLIF) and anterior lumbar interbody fusion (ALIF) are considered minimally invasive surgical methods through natural anatomical space. This study aimed to explore the corrective effects and clinical outcomes of OLIF or ALIF combined with ACR technology in patients with adult spinal deformity (ASD). METHODS: We retrospectively analyzed patients with sagittal imbalance who received OLIF and/or ALIF and ACR treatment from 2018 to 2021. Surgical time and intraoperative bleeding volume are recorded, the corrective effect is determined by the intervertebral space angle (IVA), lumbar lordosis (LL), the sagittal vertical axis (SVA), clinical outcome is evaluated by preoperative and final follow-up visual analog pain score (VAS), Japanese orthopedic association scores (JOA) and complications. RESULTS: Sixty-four patients were enrolled in the study, average age of 65.1(range, 47-82) years. All patients completed 173 fusion segments, for 150 segments of ACR surgery. The operation time of ALIF-ACR was 50.4 ± 22.1 min; The intraoperative bleeding volume was 50.2 ± 23.6 ml. The operation time and intraoperative bleeding volume of single-segment OLIF-ACR was 66.2 ± 19.4 min and 70.2 ± 31.6 ml. At the follow-up of 6 months after surgery, the intervertebral space angle correction for OLIF-ACR and ALIF-ACR is 9.2° and 12.2°, the preoperative and postoperative lumbar lordosis were 16.7° ± 6.4°and 47.1° ± 3.6° (p < 0.001), VAS and JOA scores were improved from 6.8 to 1.8 and 7.8 to 22.1 respectively, statistically significant differences were observed in these parameters. The incidence of surgical related complications is 29.69%, but without serious complications. CONCLUSION: ACR via a minimally invasive hybrid approach for ASD has significant advantages in restoring local intervertebral space angulation and correcting the overall sagittal balance. Simultaneously, it can achieve good clinical outcomes and fewer surgical complications.

Hidden blood loss of minimally invasive hybrid lumbar interbody fusion: an analysis of influencing factors.

BACKGROUND: Lumbar interbody fusion(LIF) is the leading way to treat Lumbar Degenerative Diseases(LDD). At present, there is a lack of research on the influencing factors of hidden blood loss in minimally invasive hybrid lumbar interbody fusion. This study comprehensively explores the definite factors affecting the hidden blood loss in minimally invasive hybrid lumbar interbody fusion. MATERIALS AND METHODS: One hundred patients with Lumbar degenerative diseases who underwent minimally invasive hybrid lumbar interbody fusion in our center were included. Demographics, laboratory data, surgical data, and radiographic data were collected. The Gross equation and Sehat equation were used to calculate the estimated value of hidden blood loss. Multi-factor linear regression analysis was used to determine the influencing factors of hidden blood loss. RESULT: We reviewed and collected 100 patients who underwent minimally invasive hybrid approach, mean age 65 ± 10 years, male: female 37:63; 17 patients of diabetes and 83 patients of non-diabetes; Total blood loss was 645.59 ± 376.37 ml, hidden blood loss was 421.39 ± 337.45 ml, the hidden blood loss percentage was 57 ± 26%. Results from the multi-factorial linear regression model: Diabetes (p < 0.05), hypertension (p < 0.05), psoas thickness (p < 0.05) and dorsal extensor group thickness (p < 0.05) were potential risk factors for postoperative hidden blood loss. CONCLUSION: Although minimally invasive hybrid approach is minimally invasive surgery, there is still a significant amount of hidden blood loss. There is a greater risk of blood loss in diabetes, hypertension and preoperative MRI assessment of thickness of the psoas, thickness of the dorsal extensor group.

[Effect of water depths on hydraulic performance of pond wetlands].

Pond wetlands have been widely used in the treatment of drainage water from paddy fields. However, wetland hydraulic performance and purification effects are affected by many factors, such as water depth, flow rate, aspect ratio and vegetation distribution, and the better understanding of these factors would be helpful to improve the quality of wetland design, operation and management. This paper analyzed the effect of three different water depths (20, 40 and 60 cm) on the hydraulic performance of pond wetland through the dye tracer experiments with Rhodamine WT. The hydraulic indices, i. e., effective volume ratio, nominal serial complete mixing tanks (N), hydraulic efficiency (λ), were selected for analysis through the hydraulic residence time distribution (RTD) curve. The results showed that the effective volume rate rose from 0.421 to 0.844 and the hydraulic efficiency from 0.281 to 0.604 when the water depth declined from 60 cm to 20 cm. This indicated that the wetland hydraulic performance improved as the water depth decreased. In addition, the hydraulic performance of the first half of the wetland was significantly better than that of the second half. The flow regime of the first half approached complete mixing because of the mixing index (N) approaching 1 and its effective volume rate was above 0.9 when the water depth was relatively low (20 and 40 cm). The normalized RTD curves demonstrated a good agreement between moment analysis parameters and hydraulic parameters, and a great consistency between the hydraulic parameters and moment index which was not affected by tail truncation error. The experimental study concluded that a lower water depth was favorable to improve the hydraulic performance of pond wetlands.

[Surgical intervention and radiotherapy outcome of solitary plasmacytoma of cervical spine].

OBJECTIVE: To study the clinical features, treatment methods and outcome of solitary plasmacytoma of cervical spine. METHODS: From January 1995 to December 2007, the data of 23 cases with solitary plasmacytoma of cervical spine was analyzed. There were 16 males and 7 females (mean age 56 years, range: 32 - 76 years). Two cases underwent radiotherapy alone and 21 patients received surgery. According to WBB staging system, surgical procedures were defined as total or subtotal resection (6 cases), appendix resection (4 cases), sagittal resection (3 cases) and total spondylectomy (8 cases). All surgical cases were managed using an anterior approach, posterior approach or combined anterior and posterior approach. The cervical spinal reconstruction was achieved through anterior cervical titanium plate and titanium mesh cage filled with auto iliac graft or bone cement, or anterior and posterior combined instrumented fusion. All patients received radiotherapy as adjunctive therapy. RESULTS: Follow-up of the 23 cases lasted 24.0 - 143.0 months (mean: 64.7 months). Neck pains obviously improved, and nerve compression symptoms disappeared or improved after surgery. Neurological function improved by 1 - 2 grades based on Frankel grading system. All the internal fixations were fused well and stability of the cervical spine was fine and no spine instability could be seen in our series. The bone graft fusion rate was 100%. During the follow-up period, 6 surgical cases had local recurrence and finally progressed to multiple myeloma (MM) and 3 died. Two cases without surgical treatment progressed to MM in 1 year and 1.5 years after confirmed diagnosis. They were given systemic chemotherapy. The other 15 patients had disease-free survival and after surgery and adjunctive radiotherapy. Obvious abnormity were not found in such examinations as M protein, bone marrow aspiration and emission computed tomography or PET-CT examinations. CONCLUSIONS: Solitary plasmacytoma of cervical spine is rarely seen clinically. Surgery is recommended as the primary management for patients with overt bone destruction and spinal instability or neurological dysfunction. Tumor excision with adjunctive radiotherapy can obviously reduce local recurrences and lower the possibility of progression to MM. The patients with progression to MM should receive chemotherapy according to chemotherapy protocol while the prognosis is comparatively worse.