[Clinical study of lumbar fusion by hybrid construct of stem cells technique and biodegradable material].
OBJECTIVE
To explorer the effectiveness of enriched bone marrow stem cells technique for lumbar fusion.


METHODS
With the randomization and control principles, 2 graft materials [Enrichment bone marrow mesenchymal stem cells hybridized with beta-tri calcium phosphate (composite graft group), autologous iliac crest bone graft (autograft group)] were compared in posterior lumbar fusion procedures. 56 patients with degenerative disc disease, lumbar instability or spinal stenosis, were included. The volume of cells suspension in pre- and post-enrichment and the number of nucleated cells (NCs) were identified. The number of osteoprogenitor cells was estimated by counting the colony-forming units which express alkaline phosphatase (CFUs/ALP+). Then the efficiency of the enrichment was evaluated. Clinical follow-up with roentgenogram and Oswestry scale scores was performed for outcome evaluation.


RESULTS
(249 +/- 31) ml bone marrow per patient from bilateral iliac crests was aspirated peri-operatively. About (43 +/- 11) ml enriched bone marrow was collected. The number of NCs was concentrated from (15.9 +/- 3.3) x 10(6)/ml to (44.1 +/- 10.8) x 10(6)/ml, CFUs/ALP+ was significantly increased from (118 +/- 86)/ml to(486 +/- 305)/ml. The follow-up was about (26.3 +/- 7.5) months. There was no significant differences in age, gender, disease and fusion segments between the two groups. The fusion rate was 93.3% and 96.2% for composite graft group and autograft group, respectively (chi2 = 0.2146, P = 0.6432). There was no difference in operation time between the two group (t = 0.5243, P = 0.6022), but blood loss in composite graft group was more than that in autograft group (t = 6.4664, P < 0.01). Cell salvage for auto-transfusion could transfuse back half of the blood loss during operation. No hematoma or chronic soreness in the bone marrow donor sites of composite graft group occurred, but a little exudation or moderate swelling in the wound happened in 4 cases which disappeared under medical treatment. Meanwhile, 15.4% patients had hematoma in the iliac bone donor site and 26.9% patients had chronic soreness, but no case had wound problem in autograft group. As for Oswestry scale scores, there was no significant difference between the two groups.


CONCLUSIONS
The enrichment technique of autologous bone marrow stem cells can greatly increase the concentration of MSCs. It is a rapid and safe method used peri-operatively. The composite material of enriched MSCs and porous beta-TCP is a good bone substitute in posterior spinal fusion.
Zhang
Pu
P
Department of Orthopaedics, Shanghai Ninth People's Hospital, School of Medicine of Shanghai Jiaotong University, Shanghai 200011, China. zhang_pu@hotmail.com
Gan
Yao-Kai
YK
Tang
Jian
J
Hao
Yong-Qiang
YQ
Wang
You
Y
Sun
Yue-Hua
YH
Zhu
Zhen-An
ZA
Dai
Ke-Rong
KR
D000328:Adult; D000368:Aged; D018786:Bone Substitutes; D016025:Bone Transplantation / Q000379:methods; D002130:Calcium Phosphates; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007085:Ilium / Q000637:transplantation; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D033581:Stem Cell Transplantation; D014182:Transplantation, Autologous; D016896:Treatment Outcome
D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate