Objective This paper is to investigate the application value of multi-slice CT in clinical diagnosis of muscle and ligament closed injuries. Methods A total of 100 patients with tendon injuries or (and) ligament closed injuries admitted by the Orthopaedics Department of the Hospital were selected into the observation group, and another 100 healthy candidates were selected into the health group. All candidates underwent 16- slice spiral CT scanning, and scanning results was compared to surgical results of patients, multi-slice CT imaging features of posterior cruciate ligament with injured kneel joints and those of posterior cruciate ligament with normal knee joints were compared. Results The accuracy of multilayer spiral CT in the diagnosis of tendon injuries hit 71.15% in the comparison in surgical results, and the accuracy in diagnosis of ligament damage hit 93.75%.Compared to multi-slice CT imaging characteristics of post cruciate ligament in the health group, the post cruciate ligament angle of injured kneel joint with smaller thickness and shorter lathy diameter satisfied P < 0.05, and the differences were statistically significant. The results of CT examinations showed that patients with muscle tendon injuries suffered from abdominal symptoms including the swelling, tendon circuity, tendon thickening and patients with ligament injuries suffered from ligament circuity, fuzzy and thickened boundary, articular cavity effusion and other symptoms. Conclusion MSCT acts important diagnosis means for tendon and ligament closed injuries, it delivers diagnostic accuracy, it shows the scope and degree of congestion and edema and the availability of joint cavity effusion, and provides powerful basis for clinical diagnosis and treatment, being preferred diagnostic method of such injury.