Objective:To investigate the effect of teriparatide on residual back pain (RBP) after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fracture (OVCF).Methods:A retrospective cohort study was used to analyze the clinical data of 90 OVCF patients sustaining RBP after PKP admitted to Second Affiliated Hospital of Kunming Medical University from September 2015 to March 2019, including 18 males and 72 females, at age of 57-85 years［(68.0±5.9) years］. Teriparatide treatment was applied regularly in 32 patients (teriparatide group) and antiosteoporosis drug was administered routinely in 58 patients (routine treatment group). Visual analogue scale (VAS) and Oswestry disability index (ODI) were compared between the two groups before operation, at 24 hours, 1 month, 3 months, 6 months and 12 months after operation. Anterior vertebral body height (ABH), middle vertebral body height (MBH), kyphosis angle (KA), maintenance rate of anterior vertebral body height (MRABH), maintenance rate of middle vertebral body height (MRMBH) and difference of kyphosis angle (DKA) were measured at 24 hours and 12 months after operation to evaluate the maintenance of vertebral height and incidence of vertebral refracture. Levels of type I collagen carboxy-terminal peptide (β-CTX) and serum N-terminal osteocalcin (N-MID) were measured before operation and at 12 months after operation to evaluate the improvement of bone metabolism. The adverse reactions of teriparatide group were observed.Results:All patients were followed up for 12-36 months［(14.3±0.6)months］. VAS and ODI were decreased gradually with time in both groups (all P<0.01). There were no significant differences in VAS between the two groups before operation and at 24 hours after operation (all P>0.05). Teriparatide group showed VAS of (4.4±0.6)points, (3.2±0.5)points, (2.0±0.5)points, (1.1±0.1)points at 1, 3, 6 and 12 months after operation, significantly lower than those in routine treatment group［(4.9±0.6)points, (4.0±0.6)points, (3.2±0.7)points, (2.7±0.1)points, respectively］(all P<0.01). Teriparatide group showed ODI of 26.5±1.3 and 20.6±1.2 at 6 months and 12 months after operation, significantly lower than those in routine treatment group (28.2±1.6, 23.6±1.6) (all P<0.01). There were no significant differences in ODI between the two groups at other time points (all P>0.05). Both groups presented significantly lowered levels of ABH and MBH at 12 months after operation as compared with those at 24 hours after operation (all P<0.01). There were no significant differences in ABH or MBH between the two groups at 24 hours after operation (all P>0.05). ABH, MBH, MRABH and MRMBH in teriparatide group were (1.9±0.2)cm, (1.7±0.2)cm, 0.91±0.02 and 0.92±0.02 at 12 months after operation, significantly higher than those in routine treatment group［(1.7±0.2)cm, (1.6±0.2)cm, 0.86±0.02 and 0.87±0.02］(all P<0.01). KA in both groups showed significant increase at 12 months after operation as compared with that at 24 hours after operation (all P<0.01). There was no significant difference in KA between the two groups at 24 hours after operation ( P>0.05). KA in teriparatide group was (7.3±0.7)° at 12 months after operation, significantly lower than (9.5±0.5)° in routine treatment group ( P<0.01). DKA in teriparatide group was (5.3±1.3)° at 12 months after operation, significantly lower than (6.6±1.4)° in routine treatment group ( P<0.01). Incidence of vertebral refracture in teriparatide group was 7% (2/32), significantly lower than 35% (15/58) in routine treatment group ( P<0.05). Level of β-CTX was not significantly different between and within the two groups before operation and at 12 months after operation (all P>0.05). There was no significant difference in N-MID between the two groups before operation ( P>0.05). After treatment for 12 months, level of N-MID in teriparatide group was significantly increased［19.5 (17.6, 20.9)pg/ml］as compared with that before operation［18.2 (14.6, 21.0)pg/ml］( P<0.01), and was significantly higher than that in routine treatment group［17.6 (15.3, 19.9)pg/ml］( P<0.01). Routine treatment group showed no significant difference in level of N-MID before operation and at 12 months after operation ( P>0.05). Two patients in teriparatide group had orthostatic hypotension after treatment. Conclusion:For OVCF patients with RBP after PKP, teriparatide can effectively alleviate pain, improve motor dysfunction, maintain the height of bone cement vertebral body, reduce incidence of vertebral refracture and enhance the activity of osteoblasts, with less adverse reactions.

Objective:To investigate the risk factors of cement vascular leakage after vertebral augmentation for osteoporotic vertebral compression fracture (OVCF).Methods:A case-control study was conducted to analyze the clinical data of 217 patients with OVCF undergone vertebral augmentation [percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP)] in First and Second Affiliated Hospital of Kunming Medical University from October 2019 to October 2020. There were 79 males and 138 females, at the age range of 58-88 years [(73.1±6.9)years]. According to the occurrence of bone cement vascular leakage, the patients were divided into vascular leakage group ( n=39) and vascular leakage free group ( n=178). The gender, age, bone mineral density, time from injury to operation, anatomical position of injured vertebrae, degree of vertebral compression, integrity of posterior wall, intravertebral fissure sign, vertebrobasilar venous foramen, surgical approach, surgical method, cement injection period, cement injection speed, cement injection volume and cement injection area were recorded. Univariate analysis was used to detect the correlation of those indices with cement vascular leakage after vertebral augmentation. Multivariate Logistic regression analysis was used to identify the independent risk factors for cement vascular leakage after vertebral augmentation. Results:Univariate analysis showed that there was a correlation of cement vascular leakage after vertebral augmentation with time from injury to operation, degree of vertebral compression, integrity of posterior wall, intravertebral fissure sign, vertebrobasilar venous foramen, surgical method, cement injection period, cement injection speed, cement injection volume and cement injection area (all P<0.05), apart from gender, age, bone mineral density, anatomical position of injured vertebrae or surgical approach (all P>0.05). Multivariate Logistic regression analysis showed intravertebral fissure sign ( OR=7.00, 95% CI 1.57-31.30, P<0.05), vertebrobasilar venous foramen ( OR=7.52, 95% CI 1.94-29.16, P<0.01), PVP ( OR=10.98, 95% CI 2.51-47.94, P<0.01), injection of cement in thinning period ( OR=5.91, 95% CI 1.45-24.15, P<0.05), injection of large volume of cement ( OR=3.60, 95% CI 1.70-7.65, P<0.01) and marginal injection of cement ( OR=24.80, 95% CI 5.28-116.37, P<0.01) were significantly associated with cement vascular leakage after vertebral augmentation for OVCF. Conclusion:Intravertebral fissure sign, vertebrobasilar venous foramen, PVP, injection of cement in thinning period, injection of large volume of cement and marginal injection of cement are independent risk factors for cement vascular leakage after vertebral augmentation for OVCF.

BACKGROUND:Currently,different methods of model establishment have been derived from different injury modes of spinal cord injury.Traditional physical injury modeling methods have their own advantages and disadvantages,and there is a lack of more effective and stable animal models of spinal cord injury. OBJECTIVE:To establish a reproducible,controllable,trauma-free,low-mortality,more stable,widely applicable,and short-term postoperative care rat model of spinal cord injury. METHODS:Forty Sprague-Dawley rats with similar body mass and ages were randomly divided into a control group and an improved group,with 20 rats in each group.Animal models of spinal cord injury in the control group were constructed using a clip model method,while the improved group used a modified ligation method based on the compression method to make the spinal cord injury models using suture ligation based on fenestration.Postoperative comparisons were made between the two groups,assessing urination behavior,hematuria,pyuria(infection rate),mortality,scoliosis rate and Basso-Beattie-Bresnahan locomotor rating scale scores at 1,3,5,and 7 days after modeling. RESULTS AND CONCLUSION:Compared with the conventional modeling method,the modified ligation method based on the compression method resulted in faster recovery of urination behavior,lower hematuria rate,lower infection rate,lower mortality rate,lower scoliosis rate,and more concentrated and stable Basso-Beattie-Bresnahan scores(all below 2 points within 1 week).This proves that the modified ligation method based on compression is more suitable for the establishment of spinal cord injury models in rats.

Objective:To compare the efficacies of robot-assisted unilateral and manual unilateral/bilateral puncture kyphoplasty (PKP) for the treatment of osteoporotic thoracolumbar fracture (OTLF).Methods:A retrospective cohort study was conducted to analyze the clinical data of 64 OTLF patients admitted to First Affiliated Hospital of Kunming Medical University from April 2021 to May 2022. The patients included 28 males and 36 females, aged 57-88 years [(74.5±5.6)years]. Fracture segments were 12 patients from T 1-T 9, 32 from T 10-L 2, and 20 from L 3-L 5. All the patients were treated with PKP. Among them, 25 patients underwent manual unilateral puncture (manual unilateral group), 18 patients underwent manual bilateral puncture (manual bilateral group), and 21 patients underwent robot-assisted unilateral puncture (robot-assisted unilateral group). The operation time, channel establishment time, intraoperative blood loss, intraoperative fluoroscopy times, bone cement injection volume, and bone cement spatial distribution score were compared among the three groups. The visual analogue score (VAS), Oswestry disability index (ODI) and Cobb angle of kyphosis were compared among the three groups before operation, at 3 days and 3 months after operation, and at the last follow-up. The incidence of complications was compared. Results:All the patients were followed up for 6-10 months [(7.0±0.9)months]. The operation time of the manual unilateral group was (30.2±6.1)minutes, which was shorter than (37.9±8.9)minutes of the robot-assisted unilateral group and (49.0±10.2)minutes of the manual bilateral group; the operation time of the robot-assisted unilateral group was markedly shorter than that of the manual bilateral group (all P<0.05). The channel establishment time of the robot-assisted unilateral group was (4.7±1.4)minutes, which was markedly shorter than (10.4±4.4)minutes of the manual unilateral group and (21.7±6.2)minutes of the manual bilateral group (all P<0.05). The intraoperative blood loss of the robot-assisted unilateral group was (23.8±7.2)ml, which was less than (34.3±7.7)ml of the manual unilateral group and (55.9±18.7)ml of the manual bilateral group (all P<0.05). The number of intraoperative fluoroscopy of the robot-assisted unilateral group was (12.1±2.5)times, which was markedly less than (21.2±5.9)times of the manual unilateral group and (39.6±9.5)times of the manual bilateral group (all P<0.05). The channel establishment time, intraoperative blood loss and intraoperative fluoroscopy times of the manual unilateral group were markedly shorter or less than those of the manual bilateral group (all P<0.05). The bone cement injection volume and bone cement distribution score of the robot-assisted unilateral group were (4.7±1.3)ml and (7.9±1.2)points, which were not statistically different from (5.7±1.3)ml and (8.7±1.1)points of the manual bilateral group (all P>0.05), but were markedly higher than (3.0±1.3)ml and (5.1±1.8)points of the manual unilateral group (all P<0.05). There were no significant differences in VAS, ODI and Cobb angle among the three groups at 3 days, 3 months after operation and at the last follow-up (all P>0.05), but which were all lower than those before surgery (all P<0.05). There were no significant differences in VAS, ODI and Cobb angle among three groups before operation, at 3 days, 3 months after surgery and at the last follow-up (all P>0.05). The complication rate was 4.8% (1/21) of the robot-assisted unilateral group, 32.0% (8/25) of the manual unilateral group, and 33.3% (6/18) of the manual bilateral group, with no significant difference between the manual unilateral group and the manual bilateral group ( P>0.05), but both of which was markedly higher than that of the robot-assisted unilateral group ( P<0.05). Conclusion:Robot-assisted unilateral puncture and manual unilateral/bilateral puncture PKP can both achieve satisfactory results for the treatment of OTLF, but robot-assisted unilateral puncture has shorter channel establishment time, less intraoperative blood loss and intraoperative fluoroscopy times, and lower complication rate.