Percutaneous placement of pedicle screws is a well-established technique, however, no studies have compared percutaneous and open placement of screws in the thoracic spine. The aim of this cadaveric study was to compare the accuracy and safety of these techniques at the thoracic spinal level. A total of 288 screws were inserted in 16 (eight cadavers, 144 screws in percutaneous and eight cadavers, 144 screws in open). Pedicle perforations and fractures were documented subsequent to wide laminectomy followed by skeletalisation of the vertebrae. The perforations were classified as grade 0: no perforation, grade 1: < 2 mm perforation, grade 2: 2 mm to 4 mm perforation and grade 3: > 4 mm perforation. In the percutaneous group, the perforation rate was 11.1% with 15 (10.4%) grade 1 and one (0.7%) grade 2 perforations. In the open group, the perforation rate was 8.3% (12 screws) and all were grade 1. This difference was not significant (p = 0.45). There were 19 (13.2%) pedicle fractures in the percutaneous group and 21 (14.6%) in the open group (p = 0.73). In summary, the safety of percutaneous fluoroscopy-guided pedicle screw placement in the thoracic spine between T4 and T12 is similar to that of the conventional open technique.

Cite this article: Bone Joint J 2015;97-B:1555–61.

Pain catastrophising is an adverse coping mechanism, involving an exaggerated response to anticipated or actual pain.

The purpose of this study was to investigate the influence of pain ‘catastrophising’, as measured using the pain catastrophising scale (PCS), on treatment outcomes after surgery for lumbar spinal stenosis (LSS).

A total of 138 patients (47 men and 91 women, mean age 65.9; 45 to 78) were assigned to low (PCS score < 25, n = 68) and high (PCS score ≥ 25, n = 70) PCS groups. The primary outcome measure was the Oswestry Disability Index (ODI) 12 months after surgery. Secondary outcome measures included the ODI and visual analogue scale (VAS) for back and leg pain, which were recorded at each assessment conducted during the 12-month follow-up period

The overall changes in the ODI and VAS for back and leg pain over a 12-month period were significantly different between the groups (ODI, p < 0.001; VAS for back pain, p < 0.001; VAS for leg pain, p = 0.040). The ODI and VAS for back and leg pain significantly decreased over time after surgery in both groups (p < 0.001 for all three variables). The patterns of change in the ODI and VAS for back pain during the follow-up period significantly differed between the two groups, suggesting that the PCS group is a potential treatment moderator. However, there was no difference in the ODI and VAS for back and leg pain between the low and high PCS groups 12 months after surgery.

In terms of minimum clinically important differences in ODI scores (12.8), 22 patients (40.7%) had an unsatisfactory surgical outcome in the low PCS group and 16 (32.6%) in the high PCS group. There was no statistically significant difference between the two groups (p = 0.539).

Pre-operative catastrophising did not always result in a poor outcome 12 months after surgery, which indicates that this could moderate the efficacy of surgery for LSS.

Cite this article: Bone Joint J 2015;97-B:1546–54.

We analysed the CT scans and radiographs of 76 vertebrae in 49 patients who underwent vertebroplasty for painful osteoporotic compression fractures. Leaks of cement were classified into three types: those via the basivertebral vein (type B), via the segmental vein (type S), and through a cortical defect (type C).

More leaks were identified on CT scans than on radiographs by a factor of 1.5 (74/49). Most type-B (93%) and type-S (86%) leaks were missed or underestimated on a lateral radiograph which is usually the only view used during the injection of cement. Of the leaks into the spinal canal, only 7% (2/28) were correctly identified on radiographs. The areas on lateral radiographs where this type of leak may be observed were divided into four zones, and their diagnostic value in predicting a leak into the spinal canal was evaluated. The results showed that cement in the neural foramina had the highest positive predictive value (86%).