Total lumbar disc replacement is an alternative to interbody fusion for the effective treatment of symptomatic degenerative disc disease. This paper reviewed the history of ball-on-socket type artificial lumbar disc (ALD) prosthesis, which is a typical ALD prosthesis and summarized the ALD prosthesis research progress, according to different materials such as metal-on-metal, metal-on-polymer, and polymer-on-polymer prosthesis. The structural design factors of ball-on-socket type ALD prosthesis were analyzed and its prospect of development was also presented. The purpose of this paper is to provide a theoretical reference for the design of the ball-on-socket ALD prosthesis by reviewing the current state of ball-on-socket type ALD prosthesis.

Objective: To investigate the effect of exogenous L-Arg on the survival of extended perforator flap in rats. Methods: Sixteen male Sprague Dawley rats were randomly divided into L-Arg group (n=8) and control group(n=8). The extended dorsal three-vascular territory perforator flaps were made in rats. L-Arg (400 mg·kg^-1·d^-1) was injected intraperitoneally in L-Arg group 1d before operation, immediately and 1-7 d after operation, while the same volume of saline was injected intraperitoneally in control group at the same time points. The appearance and distribution of blood vessels were observed, and the flap survival areas were measured 7d after operation. The tissue samples were harvested from choke zone Ⅱ for histological study and the expression of vascular endothelial growth factor (VEGF) was detected by immunohistochemistry and Western blot, respectively. Results: After 7d, the clearer vascular structure and more new vessels in choke zone Ⅱ were observed in L-Arg group. The survival rate of flap in L-Arg group was (88.42±4.19)%, which was significantly higher than that in control group[(76.52±5.37)%, t=3.707, P<0.01]. The microvessel density and caliber of choke zone Ⅱ in L-Arg group was (29.47±5.28)/mm² and(47.27±5.32)μm, which were significantly higher than those in control group (t=2.694 and 2.389, P<0.05 or P<0.01). The immunohistochemistry and Western blot showed that the expression of VEGF in choke zone Ⅱ of L-Arg group was significantly higher than that in control group (t=9.428 and -3.054,P<0.05 or P<0.01). Conclusion: Exogenous L-Arg can increase the survival rate of extended dorsal perforator skin flap through promoting vascularization and dilatation of vessels in choke zone Ⅱ in rats.
Animals ; Arginine ; pharmacology ; Graft Survival ; drug effects ; Male ; Neovascularization, Physiologic ; drug effects ; Perforator Flap ; blood supply ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Skin ; drug effects ; Vascular Endothelial Growth Factor A ; metabolism