Objective: The nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is a novel bioactive nonmetal cage that is now used in some medical centers, while the polyetheretherketone (PEEK) cage is a typical device that has been widely used for decades with excellent clinical outcomes. This study was performed to compare the long-term radiographic and clinical outcomes of these two different cages used in transforaminal lumbar interbody fusion (TLIF). Methods:In this retrospective and matched-pair case control study, we included 200 patients who underwent TLIF from January 2010 to December 2014 with a minimum 7-year follow-up. One hundred patients who used n-HA/PA66 cages were matched with 100 patients who used PEEK cages for age, sex, diagnosis, and fusion level. The independent student's t-test and Pearson's chi-square test were used to compare the two groups regarding radiographic (fusion status, cage subsidence rate, segmental angle [SA], and interbody space height [IH]) and clinical (Oswestry Disability Index [ODI], and Visual Analog Scale [VAS] for back and leg) parameters preoperatively, postoperatively, and at the final follow-up. Results:The n-HA/PA66 and PEEK groups had similar fusion rates of bone inside and outside the cage at the final follow-up (95.3% vs 91.8%, p = 0.181, 92.4% vs 90.1%, p = 0.435). The cage union ratios exposed to the upper and lower endplates of the n-HA/PA66 group were significantly larger than those of the PEEK group (p < 0.05). The respective cage subsidence rates in the n-HA/PA66 and PEEK groups were 10.5% and 17.5% (p = 0.059). There were no significant differences between the two groups in the SA, IH, ODI scores, or VAS scores at any time point. The n-HA/ PA66 group showed high fusion and low subsidence rates during long-term follow-up. Conclusion:Both n-HA/PA66 and PEEK cages can achieve satisfactory long-term clinical and radiographic outcomes in TLIF. However, the n-HA/PA66 group showed significantly larger cage union ratios than the PEEK group. Therefore, the results indicated that the n-HA/PA66 cage is an ideal alternative material comparable to the PEEK cage in TLIF.

Background: Both the anterior and combined anterior and posterior approaches have been used to treat lumbosacral tuberculosis. However, long-term follow-up studies of each approach have not been conducted. We aimed to compare the long-term clinical and radiographical outcomes between the two approaches.Methods: We included 49 patients with a minimum 6-year follow up between January 2008 to March 2012. Twenty-four patients underwent the anterior approach (group A) and 25 underwent the combined anterior and posterior approach (group B). We collected clinical data, such as visual analogue scale scores, Oswestry disability index scores and neurological status, and radiographical data, such as lumbosacral angle and lumbar lordosis. Furthermore, operative time, length of stay, and intraoperative and postoperative blood loss (IBL, PBL) were recorded.Results: Both groups had satisfactory clinical and radiographical outcomes until follow up. All patients achieved bony fusion, and no group differences were found in any of the clinical indices. Both groups corrected and maintained lumbosacral angle and lumbar lordosis. However, operative time, length of stay,

ObjectiveCervical tuberculosis (CTB) readily causes local kyphosis, and its surgical strategy remains controversial. Although some previous studies suggested that the anterior approach could effectively treat CTB, patients in these studies only suffered mild to moderate kyphosis. Therefore, little is known about whether the anterior approach can achieve satisfactory outcomes in CTB patients with severe kyphosis. This study was performed to evaluate the safety and efficacy of preoperative skull traction combined with anterior surgery for the treatment of CTB patients with a severe kyphosis angle of more than 35°.MethodsIn this retrospective study, we enrolled 31 CTB patients with severe kyphosis who underwent preoperative skull traction combined with anterior surgery from April 2015 to January 2021. Patients were followed up for at least 2 years. Clinical data, such as operative time, blood loss, and postoperative hospital stay, were collected. The clinical outcomes included American Spinal Injury Association (ASIA) spinal cord injury grade, Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, and related complications. The radiological outcomes included the Cobb angle of cervical kyphosis at each time point and the bony fusion state. Clinical efficacy was evaluated by paired Student's t‐test, Mann–Whitney U‐test, and others.ResultsSix patients had involvement of one vertebra, 21 had involvement of two vertebrae, and four had involvement of three vertebrae. The most common level of vertebral involvement was C4‐5, whereas the most common apical vertebra of kyphosis was C4. The mean kyphosis angle was 46.1° ± 7.7° preoperatively, and the flexibility on dynamic extension‐flexion X‐rays and cervical MRI was 17.5% ± 7.8% and 43.6% ± 11.0%, respectively (p = 0.000). The kyphosis angle significantly decreased to 13.2° ± 3.2° after skull traction, and it further corrected to −6.1° ± 4.3° after surgery, which was well maintained at the final follow‐up with a mean Cobb angle of −5.4° ± 3.9°. The VAS and JOA scores showed significant improvement after surgery. The erythrocyte sedimentation rate (ESR) and C‐reactive protein (CRP) levels normalized at 3 months after surgery. All patients achieved solid bone fusion, and no complications related to the instrumentation or recurrence were observed.ConclusionPreoperative skull traction combined with anterior debridement, autologous iliac bone grafting, and internal plate fixation can be an effective and safe surgical method for the treatment of cervical tuberculosis with severe kyphosis. Skull traction can improve the safety and success rate of subsequent anterior corrective surgery.

Objective Postoperative ileus (POI) is a relatively common complication after spinal fusion surgery, which can lead to delayed recovery, prolonged length of stay and increased medical costs. However, little is known about the incidence and risk factors of POI after corrective surgery for patients with adolescent idiopathic scoliosis (AIS). This study was performed to report the incidence of POI and identify the independent risk factors for POI after postoperative corrective surgery. Methods In this retrospective cohort study, A total of 318 patients with AIS who underwent corrective surgery from April 2015 to February 2021 were enrolled and divided into two groups: those with POI and those without POI. The Student's t test, Mann–Whitney U test, and Pearson's chi‐square test were used to compare the two groups regarding patient demographics and preoperative characteristics (age, sex and the major curve type), intraoperative and postoperative parameters (lowest instrumented vertebra [LIV], number of screws, and length of stay), radiographic parameters (T5–12 thoracic kyphosis [TK], T10–L2 thoracolumbar kyphosis and height [TLK and T10–L2 height], L1–S1 lumbar lordosis [LL], and L1–5 height). Then, a multivariate logistic regression analysis was used to identify independent risk factors for POI, and a receiver operating characteristic (ROC) curve was performed to assess the predictive values of these risk factors. Results Forty‐two (13.2%) of 318 patients who developed POI following corrective surgery were identified. The group with POI had a significantly longer length of stay, more lumbar screws, higher proportions of a major lumbar curve and lumbar anterior screw breech, and a lower LIV. Among radiographic parameters, the mean lumbar Cobb angle at baseline, the changes in the lumbar Cobb angle, and T10–L2 and L1–5 height from before to after surgery were significantly larger in the group with POI than in the group without POI. Multivariate logistic regression analysis showed that large changes in T10–L2 (odds ratio [OR] =2.846, P = 0.007) and L1–5 height (OR = 31.294, p = 0.000) and lumbar anterior screw breech (OR = 5.561, P = 0.006) were independent risk factors for POI. The cutoff values for the changes in T10–L2 and L1–5 height were 1.885 cm and 1.195 cm, respectively. Conclusion In this study, we identified that large changes in T10–L2 and L1–5 height and lumbar anterior screw breech were independent risk factors for POI after corrective surgery. Improving the accuracy of pedicle screw placement might reduce the incidence of POI, and greater attention should be given to patients who are likely to have large changes in T10–L2 and L1–5 height after corrective surgery.

Objective: There has been increasing concern about the importance of sagittal alignment in the evaluation and treatment of spinal scoliosis. However, recent studies have only focused on patients with mild to moderate scoliosis. To date, little is known about the sagittal alignment in patients with severe and rigid scoliosis (SRS). This study was performed to evaluate the sagittal alignment in patients with SRS, and to analyze how it was altered after corrective surgery. Methods:In this retrospective cohort study, we included 58 patients with SRS who underwent surgery from January 2015 to April 2020. Preoperative and postoperative radiographs were reviewed, and the sagittal parameters mainly included thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacrum slope (SS), and sagittal vertical axis (SVA). The sagittal balance state was evaluated according to whether the PI minus the LL (PI-LL) was less than 9 , and the patients were divided into thoracic hyperkyphosis and normal groups based on whether the TK exceeded 40 . The Student's t test, Pearson's test, and Receiver operating characteristic (ROC) curve analysis were used to compare related parameters between the different groups. Results:The mean follow-up duration was 2.8 years. Preoperatively, the mean PI was 43.6 AE 9.4 , and the mean LL was 65.2 AE 13.9 . Sixty-nine percent of patients showed sagittal imbalance, and they showed larger TK and LL values and smaller PI and SVA values than those with sagittal balance. Additionally, most patients (44/58) presented with thoracic hyperkyphosis; this group had smaller PI and SVA values than the normal patients. Patients with syringomyelia-associated scoliosis were more likely to present with thoracic hyperkyphosis. The TK and LL values were significantly decreased, and 45% of patients with preoperative sagittal imbalance recovered after surgery. These patients had a larger PI (46.4 AE 9.0 vs 38.3 AE 8.8 , P = 0.003) and a smaller TK (25.5 AE 5.2 vs 36.3 AE 8.0 , P = 0.000) at the final follow-up. Conclusion:Preoperative sagittal imbalance appears in the majority of SRS patients, accounting for approximately 69% of our cohort. Patients with small PI values or syringomyelia-associated scoliosis were more likely to present with thoracic hyperkyphosis. Sagittal imbalance can generally be corrected by surgery, except in patients with a PI less than 39 . To achieve good postoperative sagittal alignment, we recommend controlling the TK to within 31 .