Effect of various short-term storage methods on viability of cancellous bone fragments

Abstract

Objective - To determine effects of various storage methods on ex vivo viability of cancellous bone fragments. Sample Population - Cancellous bone fragments obtained from 4 New Zealand White rabbits. Procedure - Cancellous bone fragments were stored for 3 hours on ice in 1 of 5 preservation solutions or in 0.9% NaCl. Fragments were then reperfused (37 C) in oxygenated physiologic buffer solution for 1 hour. Cellular viability in fragments was assessed by ethidium monoazide labeling and fluorescence microscopy. Results - Viability in fresh cancellous bone ranged from 85 to 100% (mean ± SEM, 88 ± 7%). Storage of fragments significantly reduced viability. Viability in bone fragments stored at 22 C in blood-soaked sponges or 0.9% NaCl solution was 63.8 ± 3 and 65.2 ± 7%, respectively. Use of cold 0.9% NaCl solution reduced viability to 53.6 ± 3%. Viability was significantly better for fragments stored in cold phosphate-buffered sucrose (70.4 ± 2%) and EuroCollins (71.4 ± 3%) solutions. After warm reperfusion, viability was best for fragments stored in cold phosphate-buffered sucrose (70.2 ± 4%), EuroCollins (72.6 ± 3%), or UW lactobionate solutions (69.6 ± 3%), compared with those stored in cold 0.9% NaCl (47.6 ± 3%) or hypertonic citrate (53.0 ± 3%) solutions or blood-soaked sponges (57.2 ± 3%). Conclusions - Hypothermic storage in solutions designed to prevent temperature-dependent cell injury were best for maintaining cancellous bone fragment viability. Clinical Relevance - Hypothermia may be advantageous for use in storing cancellous bone fragments during procedures that dictate a prolonged period between harvest and placement of graft fragments. (Am J Vet Res 1999;60:63-67).