An Assessment of P-15 Bone Putty in Anterior Cervical Fusion With Instrumentation

Successful fusion was based on roentgenographic examination showing: evidence of bridging trabecular bone between the involved motion segments, translational motion <3mm, and angular motion <5 degrees. If there was a lack of evidence of fusion on 12 month plain x-ray examination, a CT-scan was performed and final determination of the fusion status was made using the CT reading. The criteria for fusion on CT scans were: trabecular bone formation patterns within the intervertebral disc space and bridging bone formation that crosses the interspace.

The NDI consists of ten items addressing functional activities (personal care, lifting, reading, work, driving, sleeping, recreational activities), pain intensity, concentration and headache. For each item, there are six potential responses, describing increasing degrees of disability (no disability = 0 to total disability = 5). An overall NDI score, out of 100, is calculated by adding up the scores for each item and multiplying by two. A higher NDI score indicates greater disability.

The neurological endpoint is a binary variable. Neurologic success was assessed in the motor, sensory and reflex domains specific for the cervical spine as follows: maintenance or improvement of motor function in the elbow flexors (i.e. biceps muscle), elbow extensors (i.e. triceps muscle) and wrist extensors of both arms; maintenance or improvement of sensory function of both arms; maintenance or improvement of reflexes of both arms as measured at biceps tendon, triceps tendon and brachioradialis (supinator) reflex AND absence of Babinski reflex (if not present prior to surgery). Worsening of neurological status (neurological failure) was defined as a permanent decline in the subject's neurological status based on adjudication of accumulated neurological data by an independent blinded evaluator.

Any AE within 12 months of surgery.

The pain VAS is a continuous scale upon which the subject indicates their pain level ranging from "No pain at all" (0) to "Worst imaginable pain" (10). The change in pain is calculated by subtracting the 12 month score from the baseline score.

The pain VAS is a continuous scale upon which the subject indicates their pain level ranging from "No pain at all" (0) to "Worst imaginable pain" (10). The change in pain is calculated by subtracting the 12 month score from the baseline score.

Subjects selected one of four categories: Excellent (Improvement Greater than or Equal to 80%, Deterioration Less than 10%), Good (Improvement Greater than or Equal to 70%, Deterioration Less than 15%), Fair (Improvement Greater than or Equal to 50%, Deterioration Less than 20%) or Poor (Improvement Less than 50%, Deterioration Greater than 20%).

The SF-36 v2 (Medical Outcomes Trust, Boston, MA) is a multipurpose, patient-reported short-form health survey with 36 questions available in several languages. It yields two composite scores: one for physical health (Physical Composite Score - PCS) and one for mental health (Mental Composite Score - MCS) that are comprised of eight domains. The following domains make up the PCS: physical functioning, role-physical, bodily pain, general health. The PCS ranges from a score of 0 (lowest possible level of functioning) to a score of 100 (highest possible level of functioning).

The SF-36 v2 (Medical Outcomes Trust, Boston, MA) is a multipurpose, patient-reported short-form health survey with 36 questions available in several languages. It yields two composite scores: one for physical health (Physical Composite Score - PCS) and one for mental health (Mental Composite Score - MCS) that are comprised of eight domains. The following domains make up the MCS: vitality, social functioning, role-emotional, mental health. The MCS ranges from a score of 0 (lowest possible level of functioning) to a score of 100 (highest possible level of functioning).

Kyphosis is evaluated in degrees.