ABSTRACT
Objective To investigate the sagittal correction effect and clinical efficacy of multisegment Smith-Peterson osteotomy (SPO) and single-segment pedicle subtraction osteotomy (PSO) in the treatment of old osteoporotic vertebral compression fracture (OVCF)combined with kyphosis.Methods A retrospective case control study was conducted to analyze the clinical data of 24 patients with old OVCF combined with kyphosis admitted to Traditional Chinese Medical Hospital of Xiaoshan from February 2014 to July 2016.There were 10 males and 14 females,aged 58-72 years,with an average of 65.6 years.Thirteen patients were treated with multi-segment SPO (Group A),six of whom underwent two-segment SPO and seven underwent three-segment SPO.Eleven patients were treated with single-segment PSO (Group B).The operation time,intraoperative bleeding volume,the number of cases using cementreinforced nail track,postoperative drainage,hospitalization time and postoperative complications were compared between the two groups.Cobb angle,sagittal vertical axis (SVA),thoracic kyphosis angle (TK) and lumbar lordosis angle (LL) of kyphosis deformity were measured before operation,after operation and at the last follow-up.Oswestry Dysfunction Index (ODI) and Visual Analogue Scale (VAS) were used to evaluate the clinical efficacy at the last follow-up.Results All patients were followed up for 6-24 months,with an average of 15.4 months.The operation time of Group A was (198.1 ± 27.3)minutes,while that of Group B was (237.6 ± 36.1)minutes (P ＜ 0.05).The amount of intraoperative bleeding in Group A was (1 256.2 ± 389.4) ml,while that in Group B was (1 525.6 ±457.1)ml (P ＜ 0.05).Two patients in Group A and five patients in Group B were treated with cement-reinforced nail track (P ＜ 0.05).There was no significant difference in drainage and hospitalization time between the two groups (P ＞ 0.05).Three patients in Group A and one patient in Group B had cerebrospinal fluid leakage (P ＜ 0.05).The postoperative SVA was (1.4 ± 0.7) cm in Group A and (-1.1 ± 0.6) cm in Group B (P ＜ 0.05).No significant differences were found between the two groups in Cobb angle,TK and LL of kyphosis (P ＞ 0.05).There was no significant difference in SVA,Cobb angle,TK and LL between the two groups at the last follow-up (P ＞ 0.05).There was no significant difference in ODI and VAS between the two groups after operation and at the last follow-up (P ＞ 0.05).No complications such as spinal cord injury,embolism caused by cement leakage,extraction or rupture of pedicle screw occurred in either group.Conclusion For old osteoporotic vertebrae compressed fractures combined with kyphosis,multi-segment SPO and single-segment PSO can achieve good sagittal correction and clinical efficacy.Single-segment PSO has better correction effect and lower incidence of cerebrospinal fluid leakage,yet accompanied with disadvantages of overcorrection,screw loosening,longer operation time and more blood loss.
ABSTRACT
BACKGROUND:Adipose-derived mesenchymal stem cells are gaining widespread interest in the Achil es tendon tissue engineering and regeneration, and an enabling environment (oxygen concentration) for cellinduction and differentiation is particularly necessary. OBJECTIVE:To co-culture adipose-derived mesenchymal stem cells with primary tenocytes in standard culture condition (20%O 2 tension) and in an atmosphere of reduced oxygen (2%O 2 tension) in order to determine whether the two conditions differ in their effect on tenogenic differentiation. METHODS:Tenocytes were isolated via serial expansion in culture from several Sprague-Dawley rats’ Achil es tendons. Adipose-derived mesenchymal stem cells were purchased. After one passage, adipose-derived mesenchymal stem cells were indirectly co-cultured with tenocytes in standard culture condition (20%O 2 tension) and in an atmosphere of reduced oxygen (2%O 2 tension). Col agen 1, col agen 3, Tenomodulin, Thrombospondin-4, Scleraxis levels were compared for each culture condition at 7, 14 and 21 days fol owing co-culturing. Immunofluorescence staining was performed to evaluate production of col agen 1 and Thrombospondin-4. RESULTS AND CONCLUSION:Fol owing indirect co-culturing, hypoxic differentiated adipose-derived mesenchymal stem cells expressed higher levels of tendon-related genes and proteins than normoxic controls, which suggest that oxygen levels can significantly affect tenogenic differentiation, and hypoxia is advantageous for efficient differentiation of adipose-derived mesenchymal stem cells in vitro for tendon tissue engineering.