This study is being done to prospectively collect data on subjects having posterior cervical fusion surgery using the Medtronic Infinity system. Researchers plan to collect information from patients having this type of surgery in order to learn more about patient how patients do after the surgery, including the rate of bone healing following surgery.

The goal is for 250 patients to take part in the study or for 500 screws to be used, whichever comes first. Each patient will need a varying amount of screws to be used during their surgery. Because we are measuring the accuracy of each individual screw and the surgeon will likely use multiple screws during each surgery, it is likely that the study will reach its goal of 500 screws before 250 patients are enrolled in the study.

This is a prospective single arm study of clinical and radiological outcomes as well as surgical data from posterior cervical fusion for treating degenerative disc disease (DDD). Patients undergoing posterior cervicothoracic fusions between C2 and upper thoracic will be enrolled.

Patients will be enrolled up to 250 patients (at maximum) or 500 screws, whichever is achieved first. This will adequately power the study assuming 95% screw accuracy, which is in line with published data, and assuming precision of +/- 2% with a confidence level of 9%.

The primary objective of this study is to show that the Medtronic Infinity System is safe and effective in posterior cervicothoracic fusion surgeries. Outcomes measures and complication rates will be compared to historical controls. Secondary objectives include screw accuracy rates/revision rates which can also be compared to historical controls. Other secondary objectives aim to clarify the workflow and operative time of using the O-arm and Stealth navigation for these types of cases.

Subjects will be monitored for adverse events throughout the duration of the study, particularly at and around the time of standard of care clinical assessments. The number of CT related adverse events will be evaluated. The monitoring will be performed by the investigator and study clinical research coordinator. The monitoring will occur both when a quarter and a half of the study patients have been enrolled. The study will be stopped should any significant CT related adverse events be identified.

The following data will be collected

Patient demographic and pre-operative clinical information will include:

• Name
• Age
• Sex
• Race (self-reported)
• Vitals
• Height, weight and body mass index (BMI)
• General medical/surgical history
• Medication regimen
• Smoking status (current, former, never)
• History of alcohol/substance abuse
• PROMIS
• Neurological Assessment (strength, sensory, reflexes, Hoffmann's response, Spurling's test)
• Duration of disease
• X-rays, CT, and MRI as available

Patient surgical details to be collected will include:

• Diagnosis
• Date of surgery
• Operative Index levels
• Operative time (incision open to close)
• Implants used
• Length of hospital stay
• Estimated blood loss / Surgical complications
• Somatosensory and motor intraoperative monitoring reports

Post-operative clinical information will include:

• Medication regimen
• PROMIS
• Neurological Assessment (strength, sensory, reflexes, Hoffmann's response, Spurling's test)
• X-rays, CT, and MRI as available

Inclusion Criteria:

• ≥ 18 years old
• Symptomatic multi-level degenerative spondylosis necessitating posterior cervical arthrodesis in the subaxial cervicothoracic spine (between C2-upper thoracic).
• Surgery performed within the Department of Neurological Surgery at The Ohio State University Wexner Medical Center (OSUWMC)

Exclusion Criteria:

• Traumatic injury
• Co-morbidity requiring medication use that may interfere with bone or soft tissue healing (i.e., high dose oral or parenteral glucocorticoids, immunosuppressive agents, methotrexate) - at discretion of investigator
• Severe co-morbidities (e.g., heart, respiratory, or renal disease)
• Clinically diagnosed osteoporosis
• Recent (<3 yrs) or co-incident spinal tumor or infection
• Concurrent involvement in another investigational drug or device study that could confound study data
• History of substance abuse (recreational drugs, prescription drugs or alcohol) that could interfere with protocol assessments and/or with the subject's ability to complete the protocol required follow-up
• Subjects who are pregnant or plan to become pregnant in the next 24 months
• Prisoner
• Other contraindications for Medtronic Infinity System

Patients undergoing posterior cervicothoracic fusions between C2 and upper thoracic will be enrolled.