Preoperative prediction of sagittal imbalance in kyphosis secondary to ankylosing spondylitis after one-level three-column osteotomy.

BACKGROUND: This study aimed to determine preoperative predictors for sagittal imbalance in kyphosis secondary to ankylosing spondylitis (AS) after one-level three-column osteotomy. METHODS: A total of 55 patients with AS who underwent one-level three-column osteotomy were enrolled. The patients were divided into two groups according to sagittal vertical axis (SVA) value at the final follow-up (group A: SVA > 5 cm; group B: SVA ≤ 5 cm). The radiographic measures included global kyphosis, lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), sacral slope, T1 pelvic angle (TPA), SVA, osteotomized vertebral angle and PI and LL mismatch (PI - LL). Postoperative clinical outcomes were evaluated using Scoliosis Research Society-22 questionnaire (SRS-22) and Oswestry Disability Index (ODI). RESULTS: Fifty-five AS patients had an average follow-up of 30.6 ± 10.2 months (range 24-84 months). Group A had larger preoperative and postoperative LL, PT, PI - LL, TPA and SVA values compared with group B (P < 0.05), and no significant differences were found in ODI and SRS-22 scores between the two groups (P > 0.05). Preoperative LL, PT, PI - LL, TPA, and SVA values were positively correlated with the follow-up SVA value (P < 0.05). Among them, TPA > 40.9°, PI - LL > 32.5° and SVA > 13.7 cm were the top three predictors with the best accuracy to predict sagittal imbalance. Immediate postoperative SVA value of ≤ 7.4 cm was a key factor in reducing the risk of sagittal imbalance during follow-up. CONCLUSIONS: Preoperative TPA > 40.9°, PI - LL > 32.5° and SVA > 13.7 cm could predict sagittal imbalance in AS kyphosis after one-level three-column osteotomy, and additional osteotomies were recommended for this condition. Immediate postoperative SVA ≤ 7.4 cm was an optimal indicator for preventing sagittal imbalance. LEVEL OF EVIDENCE: IV.

Mucoid Degeneration of the Anterior Cruciate Ligament: Characteristics and Conservative Management.

Clinical and radiographic characteristics of mucoid degeneration of the anterior cruciate ligament (MD-ACL) were poorly documented in previous literature. And the optimal management strategy for MD-ACL remains unclear. Here, we summarized the characteristics associated with MD-ACL, and evaluated the clinical outcome of conservative management to MD-ACL.A total of 18 knees in 18 patients diagnosed with MD-ACL were collected and reviewed retrospectively. Sixteen patients underwent conservative management and two patients underwent arthroscopic surgery. Baseline demographic, clinical data, and pathologic changes of knee in magnetic resonance imaging (MRI) were recorded. Clinical outcome was evaluated with Visual Analogue Scale (VAS) and Oxford Knee Score (OKS).The most common clinical characteristic in patients with MD-ACL was knee pain (18/18), and seconded by mobility limitation (38.9%, 7/18). All patients presented a typical celery stalk sign with increased signal and diffuse thickening volume in the ACL in MRI. Thirteen patients companied with meniscus tear (72.2%, 13/18), and nine complicated with cartilage injury (50.0%, 9/18). Sixteen patients who underwent conservative treatment were followed up for 21.8 months, and a positive clinical outcome was observed with VAS decreasing from 5.3 ± 2.3 to 1.5 ± 1.9 and OKS decreasing from 27.5 ± 12.7 to 17.9 ± 11.8 (p < 0.001). The post-OKS score was highly correlated with age, duration of disease, and meniscus tear (r = 0.844, 0.707, and 0.474, p < 0.05, respectively). And the post-VAS highly correlated with age (r = 0.693, p < 0.05). Two patients who underwent arthroscopic surgery were followed up for 24.5 months, and the pain and function of knee was improved.Knee pain and meniscus tear was the main characteristic of MD-ACL in clinical and radiographic exam. Conservative treatment could be an alternative management for treatment of MD-ACL with positive clinical outcome. Old age, long duration of disease and complications from meniscus tears were associated with inferior outcome of conservative treatment for MD-ACL. LEVEL OF EVIDENCE: IV.

Prediction formulae of sagittal alignment in thoracolumbar kyphosis secondary to ankylosing spondylitis after osteotomy.

To construct and validate prediction formulae of sagittal alignment in thoracolumbar kyphosis secondary to ankylosing spondylitis (AS) after osteotomy. A total of 115 AS patients who suffered from thoracolumbar kyphosis and underwent osteotomy were enrolled, with 85 patients in derivation group and 30 patients in validation group. Radiographic parameters were measured on lateral radiographs, including thoracic kyphosis, lumbar lordosis (LL), T1 pelvic angel (TPA), sagittal vertical axis (SVA), osteotomized vertebral angle, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and PI and LL mismatch (PI-LL). Prediction formulae of SS, PT, TPA and SVA were established; and their effectiveness was evaluated. There was no significant difference in baseline characteristics between the two groups (p > 0.05). In derivation group, LL and PI-LL were correlated with SS, and were then used to establish the prediction formula of SS[SS = - 12.791-0.765 × (LL) + 0.357 × (PI-LL), R2 = 68.3%]; PI and PI-LL were correlated with PT, and the prediction formula of PT were thus established[PT = 12.108 + 0.402 × (PI-LL) + 0.252 × (PI), R2 = 56.8%]; PT, PI-LL and LL were correlated with TPA, and were used to establish the prediction formula of TPA[TPA = 0.225 + 0.597 × (PT) + 0.464 × (PI-LL)-0.161 × (LL), R2 = 87.4%]; PT, PI-LL and age were correlated with SVA, and were used to establish the prediction formula of SVA[SVA = 36.157 + 2.790 × (PI-LL) + 1.657 × (Age)-1.813 × (PT), R2 = 41.5%]. In validation group, the predictive SS, PT, TPA and SVA were basically consistent with corresponding real values; and the mean error between predictive values and real values was of 1.3° in SS, 1.2° in PT, 1.1° in TPA and 8.6 mm in SVA. Postoperative SS, PT, TPA and SVA could be predicted with PI and the planned LL and PI-LL using prediction formulae, providing a method for AS kyphosis to plan postoperative sagittal alignment. Change of pelvic posture after osteotomy was quantitatively evaluated using the formulae.

c-Myb-mediated inhibition of miR-601 in facilitating malignance of osteosarcoma via augmentation of PKMYT1.

The crosstalk between osteosarcoma (OS) development and abnormally expressed microRNA (miR)-601 is not explored explicitly. Here, we identified the downregulated miR-601 in osteosarcoma (OS) through a comprehensive bioinformatics analysis of GEO Datasets. The results indicated that miR-601 was downregulated in both OS cells and tissues. The OS patients with reduced expression of miR-601 displayed worse prognosis. The results of in vitro and in vivo assay revealed that elevated miR-601 inhibited the proliferative, migratory and invasive capacities in OS cells. Mechanically, miR-601 exerted its function via targeting oncogene protein kinase membrane associated tyrosine/threonine 1 (PKMYT1) at post-transcriptional level. Moreover, miR-601 was attenuated by c-Myb at transcriptional level. Taken together, our studies reveal that miR-601 is a suppressive gene negatively correlated with malignancy of OS.

HIF-1α-mediated augmentation of miRNA-18b-5p facilitates proliferation and metastasis in osteosarcoma through attenuation PHF2.

Extensive evidence has explored the involvement of microRNAs (miRNAs) in osteosarcoma (OS). Limitedly, the concrete function of microRNA-18b-5p (miR-18b-5p) in OS remains unexplored and largely elusive. Here, we validated that miR-18b-5p significantly elevated in OS via analyzing the data from GEO database. The results showed that miR-18b-5p was overexpressed in human OS tissues and cell lines. The clinical evidence suggested that high level of miR-18b-5p was negatively correlated with the poor prognosis of OS. Meanwhile, miR-18b-5p upregulation facilitated the proliferation and metastasis of OS cells in vitro and in vivo. The mechanism exploration demonstrated that miR-18b-5p acted as a potential inhibitor of PHF2, a tumor suppressor gene, at post-transcriptional level. Moreover, hypoxia induced gene expression of miR-18b-5p was clarified to be transcriptionally mediated by HIF-1α. The clinicopathological analysis in samples of OS patients further supported that miR-18b-5p had a positive correlation with HIF-1α expression, and negative correlation with PHF2. Collectively, the present study uncovered a new molecular mechanism of OS tumorigenesis and development and miR-18b-5p might be a prognostic biomarker and potential therapeutic target for OS treatment.

Optimal immediate sagittal alignment for kyphosis in ankylosing spondylitis following corrective osteotomy.

Purpose: To investigate the optimal immediate sagittal alignment of kyphosis in ankylosing spondylitis (AS) following corrective osteotomy. Methods: Seventy-seven AS patients who underwent osteotomy were enrolled. Radiographic parameters, including global kyphosis (GK), lumbar lordosis (LL), T1 spinopelvic inclination (T1SPI), sagittal vertical axis (SVA), T1 pelvic angle (TPA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and PI and LL mismatch (PI-LL), were collected. The clinical outcome was evaluated using the Scoliosis Research Society-22 (SRS-22) questionnaire and Oswestry Disability Index (ODI). At the final follow-up, SVA > 5 cm was regarded as sagittal imbalance, and a total ODI ≤ 20 or total SRS-22 score ≥4 was considered to indicate a good clinical outcome. Results: Seventy-seven patients with an average age of 37.4 ± 8.6 years were followed up for 29.4 ± 4.2 months. At the final follow-up, GK, LL, PT, SS, TPA, and T1SPI showed some degree of correction loss (P < 0.05). The follow-up parameters could be predicted with the immediate postoperative parameters through their linear regression equation (P < 0.05). The postoperative immediate T1SPI, TPA, SVA, and PI were also highly correlated with the clinical outcome (ODI and/or SRS-22) at the final follow-up (P < 0.05). Based on the relationship, the optimal immediate sagittal alignment for obtaining good clinical outcome was determined: T1SPI ≤ 0.9°, TPA ≤ 31.5°, and SVA ≤ 9.3cm. AS patients with PI ≤ 49.2° were more likely to achieve the optimal alignment and obtained lower ODI and a lower incidence of sagittal imbalance than those with PI > 49.2° at the final follow-up (P < 0.05). Conclusion: Postoperative immediate parameters could be used to predict the final follow-up parameters and clinical outcome. The optimal postoperative immediate sagittal alignment of AS patients was T1SPI ≤ 0.9°, TPA ≤ 31.5°, and SVA ≤ 9.3 cm, providing a reference for kyphosis correction and a means for clinical outcome evaluation. Patients with a lower PI (≤49.2°) were more likely to achieve optimal alignment and obtain satisfactory clinical outcomes.