[Comparison of early clinical outcomes between SuperCap and direct anterior approaches for total hip arthroplasty].

OBJECTIVE: To compare the short-term clinical efficacy of SuperCap approach and direct anterior approach in total hip arthroplasty. METHODS: Clinical data of 70 patients who underwent minimally invasive SuperCap approach and DAA THA in January 2016 to June 2017 were retrospective analyzed. These patients were divided into two groups:SuperCap approach group(SuperCap group) and direct anterior approach group(DAA group). There were 15 males and 15 females in SuperCap group, aged from 45 to 71 years old, and the follow-up time ranged from 24 to 30 months. There were 24 males and 16 females in Group B, aged from 51 to 76 years and the follow-up time ranged from 24 to 36 months. Hemoglobin level of the 3rd day after operation, transfusion rate, acetabular abduction angle, anteversion angle and creatine kinase level of the 3rd day after operation, Harris score of 3 months and the last time, VAS score of 1 week and the last time were recorded and compared. Complications were recorded at the final follow-up. RESULTS: All patients were followed up, the follow-up time of SuperCap group ranged from 24 to 30 months, that of DAA group ranged from 24 to 36 months. No significant differences were found in hemoglobin level on the 3rd day after operation, transfusion rate, Harris score or VAS score between two group (P>0.05). There was no significant difference in Harris score between 3 months after operation and the final follow-up in both groups (P>0.05). There were no significant difference in VAS scores of 6 weeks after operation and on the final follow-up neither(P>0.05). The level of creatine kinase in SuperCap group was significant lower than that in DAA group(P<0.05). Until the final follow-up, there was no significant difference in the incidence of complications between the two groups(P>0.05). CONCLUSION: The clinical effect of minimally invasive SuperCap approach after total hip arthroplasty is comparable to that of DAA approach with less soft tissue injury. Patients can recover rapidly after operation and it is a safe and effective surgical approach for surgeons with short learning curve.

Clinical Analysis of Internal Fixation Treatment of Intra-articular Calcaneal Fractures with Titanium Plate.

To explore the clinical effect of internal fixation treatment of intra-articular calcaneal fractures with titanium plate, we used open reduction and internal fixation with titanium plate to 48 treated feet from 42 patients with intra-articular calcaneal fractures. The efficacy of surgical treatment was evaluated based on assessment of pain, function, and line of force aspects according to the American Orthopedic Foot and Ankle Society scoring system. Our data show that internal fixation with titanium plate is an effective treatment for calcaneal fractures. It provides satisfactory reduction, reliable fixation, and early rehabilitation.

Effects of adenoviral vector expressing hIGF-1 on apoptosis in nucleus pulposus cells in vitro.

The excessive apoptosis of cells of the nucleus pulposus may plays an important role in intervertebral disc (IVD) degeneration. It has been shown that the pro-inflammatory cytokine tumour necrosis factor (TNF)-α can induce disc cell apoptosis. Insulin-like growth factor (IGF)-1 can promote nucleus pulposus cell proliferation; however, whether or not IGF-1 inhibits TNF-α-induced apoptosis in the nucleus pulposus has not yet been elucidated. In this study, our objective was to create a potentially therapeutic viral vector, which could be used to achieve the enforced expression of IGF-1 in rabbit nucleus pulposus cells. Furthermore, we investigated the ability of IGF-1 to reverse TNF-α-induced apoptosis in cells of the nucleus pulposus. Isolated nucleus pulposus cells were cultured to a confluent monolayer, digested with collagenase Ⅱ and purified using trypsin and differential adhesion methods. Nucleus pulposus cells were positively identified using type Ⅱ collagen immunohistochemistry. Following transfection with adenoviral vectors engineered to overexpress recombinant human IGF-1 (Ad-hIGF-1) or TNF-α, the cells were observed under a light microscope. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) and flow cytometry (FCM) were used to assess the rate of apoptosis. The Ad-hIGF-1 viral vector was effectively transduced into the nucleus pulposus cells and increased IGF-1 expression as confirmed by RT-PCR and western blot analysis. In the TNF-α-treated group, a large number of apoptotic cells was observed that exhibited morphological changes associated with this form of cell death. Minimal apoptosis was observed in the Ad-hIGF-1-treated group and the control group showed no obvious signs of apoptosis. TUNEL assay revealed that the rate of apoptosis in the Ad-hIGF-1 group was significantly reduced compared with the TNF-α-treated group (P<0.01). This result was confirmed using FCM. The rate of apoptosis was also significantly increased in the TNF-α-exposed cells compared with the control group (P<0.01). Our findings strongly suggest that the adenoviral vector expressing hIGF-1 can successfully infect nucleus pulposus cells in vitro and effectively enhance the expression of IGF-1. In addition, IGF-1 reversed the TNF-α -induced apoptosis of nucleus pulposus cells. Thus, Ad-hIGF-1 may be useful in the development of clinical interventions for disc degeneration.

Histologic and biomechanical studies of tendon-to-bone healing after autologous and allogeneic bone transplants.

OBJECTIVES: Compare histologic and biomechanical differences of tendon-to-bone healing between autologous and allogeneic bone transplants. MATERIALS AND METHODS: Adult, healthy, New Zealand white rabbits were used to establish the extra-articular tendon-to-bone healing model with the left hind limb transplanted with allogeneic bone and the right hind limb transplanted with autologous bone. After 3, 6, and 12 weeks after the transplant, the rabbits were killed to collect tendon-to-bone specimens, and then the healing processes in tendon-to-bone interfaces were examined. RESULTS: All rabbits grew well after incision without infection and can freely move. Histologic observations 3 and 6 weeks after surgery and biomechanical test results 6 weeks after surgery were statistically different between the autologous and the allogeneic transplants (P < .05). After 12 weeks, histologic observations and biomechanical test results showed no difference between the 2 transplants (P > .05). CONCLUSIONS: Allogeneic bone transplant has a relatively slower tendon-to-bone healing than does autologous bone transplant, but finally allogeneic and autologous bone transplants have the same extent of tendon-to-bone healing.

Effects of IGF-1 on IL-1ß-induced apoptosis in rabbit nucleus pulposus cells in vitro.

Excessive apoptosis in intervertebral disc (IVD) cells is important in IVD degeneration. Interleukin (IL)-1ß has been shown to induce apoptosis in these cells. However, whether insulin-like growth factor-1 (IGF-1) inhibits IL-1ß-induced apoptosis in the nucleus pulposus remains unclear. The purpose of this study was to investigate the effects of IGF-1 on IL-1ß-induced apoptosis in the nucleus pulposus. Cells isolated from the nucleus pulposus were grown in culture to a monolayer. These cells were identified using immuno-histochemistry for type II collagen and toluidine blue staining for glycosaminoglycans. Following exposure to IGF-1 or IL-1ß, the cells were observed using light microscopy. Giemsa staining, TdT-mediated dUTP-biotin nick end-labeling (TUNEL) and flow cytometry (FCM) were used to detect the rate of early cell death, which served as an indicator of apoptosis. In the IL-1ß group, a large number of these cells underwent apoptosis and demonstrated morphological changes associated with apoptosis. A small proportion of cells exposed to IGF-1 alone underwent apoptosis. No obvious signs of apoptosis were observed in the control group. TUNEL results revealed that the rate of apoptosis in the IGF-1 group was significantly reduced compared with that in the IL-1ß group (P<0.01), confirmed using FCM. Compared with the control group, the apoptotic rate was also significantly increased in IL-1ß-exposed cells (P<0.01). These findings strongly suggested that IGF-1 inhibits IL-1ß-induced apoptosis in the nucleus pulposus.

[Effects of bone morphogenetic protein-2 gene therapy on the bone-implant interface: an experimental study with dogs].

OBJECTIVE: To investigate the effects of bone morphogenetic protein-2 (BMP-2) gene therapy on the bone-implant interface in the reconstruction of periprosthetic bone defect. METHODS: Transverse defects were caused in the external condylae of both femurs of 14 adult Beagle dogs. Titanium alloy implants were inserted and a bone defect 3 mm wide around the titanium alloy implant was preserved. Then the total 28 defects were divided into 4 groups: 8 bone defects remained untreated (blank control group); 8 bone defects were implanted with heterogeneous freeze-dried bone by impaction grafting technique (non-cell group); 8 bone defects were implanted with heterogeneous freeze-dried bone loaded with autogenous bone marrow stromal cells (BMSCs) from the greater trochanter of the same dog (cell group); and 10 bone defects were implanted with freeze-dried allograft loaded with autogenous BMSCs from the greater trochanter of the same dog which were transfected by Adv-BMP-2 gene (gene group). Three, 6, and 12 weeks after implantation X-ray examination was carried out to observe the place of the implant and the absorption of the implants. Six and 12 weeks after the dogs were killed and their bone defects were taken out to undergo histological, histomorphometric and biomechanical examination to observe the healing and oseeointegration of the bone-implant interface. RESULTS: Histological examination showed that 6 weeks after implantation new bone formation was found on the implant surface and there was point contact between the bone and implant in the gene group with the bone-to-impact contact (BIC) of about 10%; and continuous soft tissue was found at bone-implant interface in all other groups. Twelve weeks after, there was thick soft tissue membrane between the new bone and implant in the blank control group; most of the interface was connective fibrous tissue in the non-cell group and cell group with point contact between the bone and implant and a BIC lower than 10%; and in the gene group the interface consisted mainly of bone tissue and continuous bone-implant contact was found with the BIC of 50%, significantly higher than those of the other 2 groups (both P < 0.01). The mechanical strength of interface increased time-dependently in all groups, that of the gene group being significantly higher than those of the other 2 groups at any time-points (both P < 0.01). CONCLUSION: BMP-2 gene therapy can improve the osseointegration of bone-implant interface.