Jin Yuan-Zhe, Zheng Guang-Bin, Cho Minjoon, Lee Jae Hyup
Department of Orthopedic Surgery, College of Medicine, Seoul National University, Seoul, 03080, South Korea.
The First Hospital of Jilin University, Changchun City, 130021, China.
Biomater Res. 2021 Oct 21;25(1):34. doi: 10.1186/s40824-021-00237-3.
Bone substrates like hydroxyapatite and tricalcium phosphate have been widely used for promoting spinal fusion and reducing the complications caused by autograft. Whitlockite has been reported to promote better bone formation in rat calvaria models compare with them, but no study investigated its effect on spinal fusion yet. Also, the higher osteoinductivity of whitlockite raised concern of ectopic ossification, which was a complication of spinal fusion surgery that should be avoided.
In this study, we compared the osteoinductivity of whitlockite, hydroxyapatite, and tricalcium phosphate porous particles with SD rat spine posterolateral fusion model and investigated whether whitlockite could induce ectopic ossification with SD rat abdominal pouch model.
The micro-CT result from the posterolateral fusion model showed whitlockite had slightly but significantly higher percent bone volume than tricalcium phosphate, though none of the materials formed successful fusion with surrounding bone tissue. The histology results showed the bone formed on the cortical surface of the transverse process but did not form a bridge between the processes. The result from the abdominal pouch model showed whitlockite did not induce ectopic bone formation.
Whitlockite had a potential of being a better bone substrate hydroxyapatite and tricalcium phosphate in spinal fusion with low risk of inducing ectopic ossification.
羟基磷灰石和磷酸三钙等骨基质已被广泛用于促进脊柱融合并减少自体骨移植引起的并发症。据报道，与它们相比，白磷钙矿在大鼠颅骨模型中能促进更好的骨形成，但尚无研究调查其对脊柱融合的影响。此外，白磷钙矿较高的骨诱导活性引发了对异位骨化的担忧，而异位骨化是脊柱融合手术应避免的一种并发症。
在本研究中，我们用SD大鼠脊柱后外侧融合模型比较了白磷钙矿、羟基磷灰石和磷酸三钙多孔颗粒的骨诱导活性，并用SD大鼠腹袋模型研究了白磷钙矿是否会诱导异位骨化。
后外侧融合模型的显微CT结果显示，白磷钙矿的骨体积百分比略高于磷酸三钙，但所有材料均未与周围骨组织成功融合。组织学结果显示，骨在横突皮质表面形成，但未在横突之间形成骨桥。腹袋模型的结果显示，白磷钙矿未诱导异位骨形成。
在脊柱融合方面，白磷钙矿有潜力成为比羟基磷灰石和磷酸三钙更好的骨基质，且诱导异位骨化的风险较低。
