Materials and Methods

We included in our study 100 patients who underwent ACDR in our Spinal Unit (between May 2006 – May 2010). We used as clinical outcome measures: Visual Analogue Score for neck pain (VAS-NP) and arm pain (VAS-AP), Neck Disability Index (NDI) and Bodily Pain (SF36-BP) component of the Short Form 36 questionnaire. Statistics were obtained using SPSS 16.0 for Windows (SPSS Inc, Chicago, IL). Independent sample t-test for normally distributed data and Man-Whitney U test for non-parametric data were used. Statistical significance was designated at p < 0.05.

Methodology and Results

36 patients with radiculopathy/myelopathy, who failed to respond to conservative measures, were included. Pain and function were evaluated by Visual Analogue score for Neck pain (VAS-NP) and Arm pain (VAS-AP), Neck disability index (NDI) and SF-36 questionnaires. Radiological assessments include assessing overall range of movement (ROM) and at functional segment unit (FSU). Statistical analysis was completed using SPSS 16.0 statistical package (SPSS Inc, Chicago, IL). Appropriate parametric (A paired t-test) and non parametric tests (Wilcoxon signed-rank test) were used to assess the statistical significance (p<0.05).

The average age at operation was 51 years (range 35 - 77years). 8 patients received ACDR at one-level, 15 had 2-level surgery, 12 had 3-level surgery and 1 had a 4-level surgery. At the time of final follow-up (Mean 14.25 months, Range 12- 22.5 months) the mean NDI improved from 49.35; to 33.78 (p< 0.001). There statistically significant improvement note in VAS-NP (Post-op3.65, Pre-op:8.16, p<0.001), VAS-AP (Post-op:3.12, Pre-op:7.32, p<0.001) and SF-36BP (pre-op:29.15, post-op:37.18, p<0.002). The overall global ROM movement was preserved (pre-op:46.80±10.52, post-op:45.04±11.53) and an improvement in ROM at FSU was observed (pre-op:16.60±8.50, post-op:20.22±12.22) at final follow–up.

Methodology and Results

The pain intensity was evaluated using the Visual Analogue Score for back pain (VAS-BP) and leg pain (VAS-LP) and functional outcomes using Oswestry Disability Score (ODS). Overall improvement in general patient's health was assessed using the Bodily Pain (SF36-BP) component of the SF -36 questionnaires. Data was analysed with the SPSS 16.0 for Windows (SPSS Inc, Chicago, IL). Statistical significance was designated at p < 0.05 and appropriate parametric (Paired sample t-test) and non parametric tests (Wilcoxon signed-rank test) were used.

There were 3 male and 19 female patients and average age at operation was 68.95 years (57-79 years). The average duration of follow up was 16.18 months (8-37 months). Most common level of surgery was L4/5 (n=18). Decompression and instrumentation involved 1 level (7 cases), 2 levels (9 cases), 3 levels (1 case) and 4 levels (5 cases). There was statistically significant improvement in all clinical outcomes. The ODS improved from 49.45 ±14.35 pre-operatively to 22.91 ± 6.38 post operatively (p< 0.001). There was statistically significant improvement noted in VAS-BP (p< 0.001), VAS-LP (p<0.001) and SF36-BP (p=0.002).

Methodology and Results

This is a prospective, blinded, randomised study on imaging of cervical arthroplasty devices. The pre and postoperative MRI images of 16 patients who underwent cervical arthroplasty using Prestige LP(r) (Medtronic Sofamor Danek) and NuNec(tm) Cervical Arthroplasty System (Pioneer Surgical Technology, Marquette, Mich., USA) were assessed. Two independent radiologists who were blinded and provided with a sets of random images to score using a four point Jarvick grading system. Statistical analysis was completed using SPSS 16.0 statistical package (SPSS Inc, Chicago, IL) and analysis included comparing MR image quality before and after cervical arthroplasty at the operated and adjacent levels, and in between two types of implant.

The pre-operative MR image quality at operated and adjacent levels was excellent in both groups. In the post-operative images, the adjacent level visualisation was adequate in both groups without much difference in average scores. However, at operated level, the quality of MR images in the NuNec group (PEEK on PEEK articulating disc) was excellent and clear visualisation of the cord, central canal, foramen and disc.