Traffic accidents, falling from high altitude, and bruises caused by heavy objects may cause Spinal Cord Injury (SCI). SCI interrupted the transmission channel of human nerve signal. Most patients had paraplegia, lost their physical function, and had incontinence resulting in permanent disability . According to the statistics of the World Health Organization in 2016, the prevalence of SCI in the world is (258～785) per million people, and the annual incidence rate is (13.8～86) per million people. At present, there are about 6 million patients in the world, and about 600 000 people are newly added every year. SCI has been a difficult research topic in the medical community. After long-term’s research and exploration, doctors and researchers have not found an effective treatment method to repair the micro-environment and promote the regeneration of injured nerve after SCI. The method proposed in this paper focuses on the following aspects: (1) Conventional detection instruments such as X-ray, MRI, CT and others only in imaging and morphological observations, which can not locate the nerve cells in the SCI area and can not analyze the activity in real-time. As a result, doctors and researchers can’t grasp the condition of the patient accurately and it is likely to delay the patient’s condition and even endanger the patient’s life. (2) In December 2013, the quantum communication team of Xi’an University of Posts &Telecommunications proposed the quantum relay “bridge” method, which uses quantum entanglement to establish a “connection” between the upper and the lower break point of SCI to achieve human neural signal relay. And the University together with the Xi’an Jiaotong University completed the experiments on rats and rabbits which have made breakthroughs; on January 16, 2015, the Chinese Academy of Sciences regenerative medicine research team and the Chinese Armed Police Brain Hospital combined with mesenchymal stem cells and used nerves. The Cell Regeneration Scaffold completed the “first bypass” surgery for the first SCI in the world and achieved a good therapeutic effect. How to ensure that the “bridge” is built on the alive nerve cells, not on the died nerve cells? How to find a suitable “bridge pier” position so that the “bridge” distance is as short as possible to ensure that the fidelity of the neural signal transmission can be higher? By the method proposed in this paper, we can find the accurate position of nerve cells after SCI. Spectroscopic analysis techniques are widely used in the biomedical field and play a crucial role in the early detection and have a highly efficient detection in certain diseases. Neuron-specific nuclear protein can be used to specifically identify nerve cells. Since the surviving nerve cells can produce neurotransmitters, this article based on animal experiments, simulates photon transmission in biological tissues through the Monte Carlo model. Establishing a polar coordinate transformation in the plane Oxy, calculating the attenuation coefficient matrix of light in biological tissues, detecting near-infrared light at the same position before and after SCI, the clustering algorithm was used to process the neuron-specific nuclear protein and neurotransmitter detection data. Through matlab simulation, a two-dimensional distribution map of the attenuation coefficient before and after SCI was obtained. The coordinates of the voxels in the spinal cord injury area in Oxy are determined, in the anomalous part of the plane Oxy, the abnormal point W and the Z axis are selected to establish the plane Ozw, and the position coordinates of the nerve cells at the site of the SCI are finally determined. The method proposed in this paper can provide theoretical basis for doctors and researchers in the study of limb function reconstruction in patients with SCI.