Subjective and objective cervical spine mobility after two-level anterior cervical discectomy and fusion - A prospective observational trial.

INTRODUCTION: Cervical spine mobility is an important functional outcome following surgical procedures. For single-level ACDF, several studies indicated that cervical range-of-motion is not compromised and may even improve, despite fusion of the treated segment. RESEARCH QUESTION: This study investigates the cervical mobility for two-level ACDF. MATERIAL AND METHODS: Prospective, observational trial on patients prior, 3 months and 1 year after degenerative two-level ACDF concerning objective goniometric and subjective quality of their cervical range-of-motion. Pain courses for neck and arm, quality of life (SF-8, ADLs) and patient satisfaction were queried. RESULTS: 69 patients were analyzed (56.7 ± 11.0 years, 66.7% male). Goniometric range-of-motion worsened 3 months postoperatively in flexion-extension -11.5° (p < 0.001), lateral tilt -8.0° (p < 0.001) and rotation -3.6° (p = 0.062), regaining similar mobility to preoperative after 1 year (-1.5°, p = 0.700; -0.7°, p = 0.700; +2.9°, p = 1.000). Subjective range-of-motion improved significant after 3 months, and this improvement persisted even after 1 year. There was significant pain reduction at rest (NRS neck -1.2, p = 0.007; arm -2.0, p < 0.001) and under strain (NRS neck -1.5, p < 0.001; arm -2.9, p < 0.001) already after 3 months. Physical (+8.6, p < 0.001) and mental (+7.7, p = 0.065) component of SF-8 was improved and 92.8% were satisfied with the surgery. CONCLUSION: Two-level ACDF was not associated with deterioration in cervical spine mobility. Objective range-of-motion was temporarily reduced, returning to baseline after 1 year. Subjective mobility was already improved 3 months after surgery, accompanied by sustained pain reduction and improved quality of life. Consequently, concerns about postoperative motion reduction after two-level ACDF can be actively addressed.