Vertebral body versus iliac crest bone marrow as a source of multipotential stromal cells: Comparison of processing techniques, tri-lineage differentiation and application on a scaffold for spine fusion.

The potential use of bone progenitors, multipotential stromal cells (MSCs) helping spine fusion is increasing, but convenient MSC sources and effective processing methods are critical factors yet to be optimised. The aim of this study was to test the effect of bone marrow processing on the MSC abundance and to compare the differentiation capabilities of vertebral body-bone marrow (VB-BM) MSCs versus iliac crest-bone marrow (IC-BM) MSCs. We assessed the effect of the red blood cell lysis (ammonium chloride, AC) and density-gradient centrifugation (Lymphoprep™, LMP), on the extracted VB-BM and IC-BM MSC numbers. The MSC abundance (indicated by colony counts and CD45lowCD271high cell numbers), phenotype, proliferation and tri-lineage differentiation of VB-BM MSCs were compared with donor-matched IC-BM MSCs. Importantly, the MSC attachment and osteogenesis were examined when VB-BM and IC-BM samples were loaded on a beta-tricalcium phosphate scaffold. In contrast to LMP, using AC yielded more colonies from IC-BM and VB-BM aspirates (p = 0.0019 & p = 0.0201 respectively). For IC-BM and VB-BM, the colony counts and CD45lowCD271high cell numbers were comparable (p = 0.5186, p = 0.2640 respectively). Furthermore, cultured VB-BM MSCs exhibited the same phenotype, proliferative and adipogenic potential, but a higher osteogenic and chondrogenic capabilities than IC-BM MSCs (p = 0.0010 and p = 0.0005 for calcium and glycosaminoglycan (GAG) levels, respectively). The gene expression data confirmed higher chondrogenesis for VB-BM MSCs than IC-BM MSCs, but osteogenic gene expression levels were comparable. When loaded on Vitoss™, both MSCs showed a similar degree of attachment and survival, but a better osteogenic ability was detected for VB-BM MSCs as measured by alkaline phosphatase activity (p = 0.0386). Collectively, the BM processing using AC had more MSC yield than using LMP. VB-BM MSCs have a comparable phenotype and proliferative capacity, but higher chondrogenesis and osteogenesis with or without using scaffold than donor-matched IC-BM MSCs. Given better accessibility, VB-BM could be an ideal MSC source for spinal bone fusion.

Benefits of the use of blood conservation in scoliosis surgery.

AIM: To investigate whether autologous blood transfusion (ABT) drains and intra-operative cell salvage reduced donor blood transfusion requirements during scoliosis surgery. METHODS: Retrospective data collection on transfusion requirements of patients undergoing scoliosis surgery is between January 2006 and March 2010. There were three distinct phases of transfusion practice over this time: Group A received "traditional treatment" with allogeneic red cell transfusion (ARCT) in response to an intra- or post-operative anaemia (Hb < 8 g/dL or a symptomatic anaemia); Group B received intra-operative cell salvage in addition to "traditional treatment". In group C, ABT wound drains were used together with both intra-operative cell salvage and "traditional treatment". RESULTS: Data from 97 procedures on 77 patients, there was no difference in mean preoperative haemoglobin levels between the groups (A: 13.1 g/dL; B: 13.49 g/dL; C: 13.66 g/dL). Allogeneic red cell transfusion was required for 22 of the 37 procedures (59%) in group A, 17 of 30 (57%) in group B and 16 of 30 (53%) in group C. There was an overall 6% reduction in the proportion of patients requiring an ARCT between groups A and C but this was not statistically significant (χ2 = 0.398). Patients in group C received fewer units (mean 2.19) than group B (mean 2.94) (P = 0.984) and significantly fewer than those in group A (mean 3.82) (P = 0.0322). Mean length of inpatient stay was lower in group C (8.65 d) than in groups B (12.83) or A (12.62). CONCLUSION: When used alongside measures to minimise blood loss during surgery, ABT drains and intra-operative cell salvage leads to a reduced need for donor blood transfusion in patients undergoing scoliosis surgery.

A survey of current controversies in scoliosis surgery in the United Kingdom.

STUDY DESIGN: A 10-point questionnaire was constructed to identify the philosophy of surgeons on various aspects of scoliosis surgery, such as choice of implant, bone graft, autologous blood transfusion, cord monitoring, and computer-assisted surgery. Comparisons were then made with recommendations published in the spinal literature. OBJECTIVE: To determine certain aspects of the current practice of scoliosis surgery in the United Kingdom. SUMMARY OF BACKGROUND DATA: Guidelines for good clinical practice in spinal deformity surgery are available in the United Kingdom but do not cover a number of controversial issues. METHODS: Consultants and fellows attended the 2009 British Scoliosis Society meeting. Fifty questionnaires were completed by 45 consultants and 5 fellows. RESULTS: All pedicle screw constructs favored by 25 of 50, hybrid 24 of 50 (1 undecided). Posterior construct of fewer than 10 levels, 20 of 50 would not cross-link, 11 of 50 used 1, and 19 of 20 used 2 or more. More than 10 levels 17 of 50 considered cross-links unnecessary, 4 of 50 used 1 and 29 of 50 used 2 or more. Eighty-eight percent preferred titanium alloy implants, whereas others used a mixture of stainless steel and cobalt chrome. When using bone graft, respondents used bone substitutes (24), iliac crest graft (14), allograft (12) and demineralized bone matrix (9) in addition to local bone. Ten of 50 would use recombinant bone morphogenetic protein (3 for revision cases only). Thirty-nine of 50 routinely used intraoperative cell salvage and 4 of 50 never used autologous blood. All used cord monitoring: sensory (19 of 50), motor (2 of 50), and combined (29 of 50). None used computer-aided surgery. Twenty-six operated alone, 12 operated in pairs, and 12 varied depending on type of case. CONCLUSION: This survey shows interesting variations in scoliosis surgery in the United Kingdom. It may reflect the conflicting evidence in the literature.

Primary bone tumours of the spine: a 42-year survey from the Leeds Regional Bone Tumour Registry.

We conducted a review of the Leeds Regional Bone Tumour Registry for primary bone tumours of the spine since establishment in 1958 until year 2000. To analyse the incidence of primary tumours of the spine and to record the site of occurrence, sex distribution, survival and pathology of these tumours. Primary tumours of the spine are particularly rare, accounting for between 4 and 13% of published series of primary bone tumours. The Leeds Bone Tumour Registry was reviewed and a total of 2,750 cases of bone tumours and tumour-like cases were analysed. Consultants in orthopaedic surgery, neurosurgery, oncology and pathology in North and West Yorkshire and Humberside contribute to the Registry. Primary bone tumours of the osseous spine constitute only 126 of the 2,750 cases (4.6%). Chordoma was the most frequent tumour in the cervical and sacral regions, while the most common diagnosis overall was multiple myeloma and plasmacytoma. Osteosarcoma ranked third. The mean age of presentation was 42 years and pain was the most common presenting symptom, occurring in 95% of malignant and 76% of benign tumours. Neurological involvement occurred in 52% of malignant tumours and usually meant a poor prognosis. The establishment of Bone Tumour Registries is the only way that sufficient data on large numbers of these rare tumours can be accumulated to provide a valuable and otherwise unavailable source of information for research, education and clinical follow-up.