The present invention discloses the side light-emitting device that one kind can be engaged with pulp cavity guide pin. The device substantially includes the main body of a sealing, sets the front end protective device of what body front end and engagement device that one sets the what body ends, is separately provided with the intensity of light source changing device and a light transmission form of a lighting device, a power supply unit, a light scattering device, one optionally in the what main body. Movable group of the side light-emitting device of the present invention connects on the different pulp cavity guide pin of what, and the lighting device is given using power supply unit power supply, make light source caused by the lighting device through the scattering process of the light scattering device, or further appropriate intensity modulation Hou, the light transmission form through main body is to lateral direction light emission； Accordingly can what when carrying out steel nail operation in pulp cavity, shine through in apparatus of the present invention what affected part body, be that can reach from observation in vitro surgery location, accurate the effect of carrying out steel nail positioning person.本發明揭示一種可與髓腔導針接合之側向發光裝置。該裝置大致包含有一密封的主體、設於主體前端的前端保護裝置、以及一設於該主體末端的接合裝置，於該主體內另設置有一照明裝置、一供電裝置、一光線散射裝置、一視需要的光源強度調變裝置與一透光視窗。本發明之側向發光裝置可活動組接於不同的髓腔導針上，並利用該供電裝置供電予該照明裝置，使該照明裝置所產生的光源經該光線散射裝置的散射作用，或進一步的適當強度調變後，經主體的透光視窗向側向發光；據此可於進行髓腔內鋼釘手術時，透過本發明裝置於患部體內發光，乃可達到自體外觀察手術位置，準確進行鋼釘定位之功效者。
