INTRODUCTION: Over the past two decades, cervical disc arthroplasty has become one of the most common methods of treating one-segmental cervical disc herniation. However, the impact of disc arthroplasty on the biomechanics of the cervical spine hasn’t been fully explored yet. ----- AIM: The objective of this study was to investigate the effect of cervical disc arthroplasty on the biomechanics of the cervical spine by comparing the postoperative range of motion of the cervical spine in a cohort that underwent cervical arthroplasty with the preoperative range of motion, and by comparing the postoperative range of motion of the cervical spine in the cohort that had cervical arthroplasty with the range of motion of the cervical spine in the control group. ----- MATERIAL AND METHODS: 50 respondents took part in the research. The cohort consisted of 25 respondents who had their cervical disc replaced with the Discover, an artificial disc device, due to one-segmental cervical disc herniation. The control group consisted of 25 healthy respondents. All members of the cohort had their static and dynamic cervical radiographs taken before the surgery, and 3, 6, 12, and 24 months after the surgery. Members of the control group had their dynamic cervical radiographs taken. Range of motion of the cervical spine, and the range of motion of the operated functional spinal unit was determined by all radiograms in the cohort that underwent cervical arthroplasty, while the range of motion of the cervical spine was determined in the control group. The range of motion of the cervical spine was determined by adding the value of the Cobb angle of the cervical spine in maximum flexion and extension, whereas the range of motion of the operated functional spinal unit was determined by adding the value of the Cobb angle of the operated functional spinal unit in maximum flexion and extension. ----- RESULTS: Our cervical biomechanical research has shown that the range of motion of the cervical spine and the range of motion of the operated functional spinal unit increase after the Discover artificial cervical disc arthroplasty, and that one year after surgery there is no statistically significant difference between the average value of the range of motion of the cervical spine in the cohort and the control group. In addition, the research has shown that the same properties are retained two years after surgery. No cases of heterotopic ossification or signs of adjacent segment disease were found in the group of patients who underwent the Discover artificial cervical disc arthroplasty at two years post-surgery.