There is currently no consensus about the mean volume of blood lost during spinal tumour surgery and surgery for metastatic spinal disease. We conducted a systematic review of papers published in the English language between 31 January 1992 and 31 January 2012. Only papers that clearly presented blood loss data in spinal surgery for metastatic disease were included. The random effects model was used to obtain the pooled estimate of mean blood loss.

We selected 18 papers, including six case series, ten retrospective reviews and two prospective studies. Altogether, there were 760 patients who had undergone spinal tumour surgery and surgery for metastatic spinal disease. The pooled estimate of peri-operative blood loss was 2180 ml (95% confidence interval 1805 to 2554) with catastrophic blood loss as high as 5000 ml, which is rare. Aside from two studies that reported large amounts of mean blood loss (> 5500 ml), the resulting funnel plot suggested an absence of publication bias. This was confirmed by Egger’s test, which did not show any small-study effects (p = 0.119). However, there was strong evidence of heterogeneity between studies (I² = 90%; p < 0.001).

Spinal surgery for metastatic disease is associated with significant blood loss and the possibility of catastrophic blood loss. There is a need to establish standardised methods of calculating and reporting this blood loss. Analysis should include assessment by area of the spine, primary pathology and nature of surgery so that the amount of blood loss can be predicted. Consideration should be given to autotransfusion in these patients.

Cite this article: Bone Joint J 2013;95-B:683–8.

Although success has been achieved with implantation of bone marrow mesenchymal stem cells (bMSCs) in degenerative discs, its full potential may not be achieved if the harsh environment of the degenerative disc remains. Axial distraction has been shown to increase hydration and nutrition. Combining both therapies may have a synergistic effect in reversing degenerative disc disease. In order to evaluate the effect of bMSC implantation, axial distraction and combination therapy in stimulating regeneration and retarding degeneration in degenerative discs, we first induced disc degeneration by axial loading in a rabbit model.

The rabbits in the intervention groups performed better with respect to disc height, morphological grading, histological scoring and average dead cell count. The groups with distraction performed better than those without on all criteria except the average dead cell count.

Our findings suggest that bMSC implantation and distraction stimulate regenerative changes in degenerative discs in a rabbit model.