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Abstract

Purpose

To assess the effect of porous hydroxyapatite“ NEO PLUG” for suppressing subcutaneous hematoma after anterior cruciate ligament reconstruction (ACLR).

Material and method

42 knees were performed ACLR between 2012 January and 2013 October. 26 knees were included to HA group and 31 knees were included to control group. For HA group, NEO PLUG were inserted into tibial bone tunnel after the graft were settled. Both groups were used closed wound drainage system and tip of the tube was settled in front of the tibial bone tunnel. Data were collected pre- and post-operative days 1, 3 and 6. Evaluation items were following. 1) Amount of drain fluid, 2) Lab data (CRP, D-dimer), 3) Pre- post-op difference of calf girth.

Result

Drain fluid of was 71. 5± 40. 1ml (HA) and 89. 4± 40. 1ml (control). CRP of HA group on day 1, day 3, day 6 was 1. 1± 0. 7mg/dl, 4. 0± 2. 3 mg/dl, 0. 7± 0. 5 mg/dl and control group was 1. 1± 0. 8 mg/dl, 4. 4± 3. 3 mg/dl, 0. 9± 0. 9mg/dl. D-dimer of HA group on day 6 was 2. 0± 0. 8μg/dl and control group was 2. 3± 1. 1μg/dl. There were no significant difference between 2 groups in these data above. In calf girth difference, there was only significant difference on day 6 (HA： − 0. 9± 1. 2cm, control： − 0. 1± 1. 1cm).

Discussion

According to our result, it could be expected that NEO PLUG suppress subcutaneous hematoma after ACLR to some extent. In this study, we just used NEO PLUG which consists of only porous body, therefore NEO PLUG X which consists of porous body and impermeable body could be more effective to suppress subcutaneous hematoma after ACLR.

Abstract

Objective

The filling materials used in Vertebroplasty (VP) and kyphoplasty (KP) include injectable calcium phosphate cement (CPC), PMMA and others. Different filling materials have different effects on the biomechanical properties of vertebral bodies. Recollapse of the treated vertebra after VP or BKP is the one of the severe complications of the procedure, however, what characteristics of vertebral pseudoarthrosis increase the risk of recollapse remains unclear. The purpose of this study was to investigate risk factors for this complication using multiple logistic regression analysis and to compare the clinical outcomes of VP-CPC and BKP-PMMA.

Methods

A retrospective review of 49 vertebral pseudoarthrosis treated with VP using CPC and 9 vertebral pseudoarthrosis treated with BKP using PMMA was performed. The following covariates were analyzed : age, sex, body mass index, ASA physical classification system (ASA), bone mineral density, bone metabolic marker, visual analog scale (VAS) for back pain. Morphological variables, including posterior/anterior wall injury, endplate injury, anterior vertebral height restoration, kyphosis correction of treated vertebrae, were also analyzed. In this study, we made a new scoring system (vertebral wall injury score: 0- 4) based on the total numbers of the damaged vertebral wall (anterior wall /posterior wall /upper endplate. lower endplate) A higher score indicates a greater severity of injury. Multiple logistic regression analysis was used to determine the relative risk of recollapse of the treated vertebrae.

Results

The recollapse was occured in 14 nonunion of OVFs (28. 6％) in the group VP. In multivariate analysis, ASA-PS and high vertebral wall injury score were significantly associated with recollapse. There were no significant differences about the clinical outcomes, such as JOA scores and VAS, between the group VP and BKP, however, collection loss rate was lower in the BKP group than VP group and the recollapse wasn't occurred in the BKP group.

Conclusion

The BKP with PMMA may be superior treatment than the VP with CPC for the patients with vertebral pseudoarthrosis.

要旨

骨粗鬆症治療に使用されるビスホスホネート薬（BP）は強力な骨吸収抑制剤であり，その効果には骨密度上昇のみならず，椎体骨折および大腿骨近位部骨折予防のエビデンスがある．しかしながらその作用機序（破骨細胞機能低下）から骨折直後に投与すると骨折治癒過程に影響を与え，骨癒合を遷延させるという懸念がある．動物実験では新規骨折に対し骨折後に新たにBP を投与すると，仮骨は旺盛に形成され，リモデリングは遅れるが，骨強度は大となり骨癒合には支障がないとされているものが多い．一方ヒトでの研究では前向きでコントロールと比較した最近の3 研究によれば，骨折後早期にBP を投与することで骨癒合が遷延するという事実は認められなかった．早期のBP 投与により大腿骨近位部の骨密度上昇が得られ，2 次的脆弱性骨折予防に有用であると考えられる．

Abstract

Experiment 1.

Hydroxyapatite (HA) ceramics are used as implants to repair damaged/removed bone, and negative or positive electrical polarization enhances osteoblast and decreases osteoclast activity, respectively, in vivo. We compared the ability of electrically polarized and non-polarized hydroxyapatite with interconnected pores (IP-HA) implants to promote bone growth. Polarized or non-treated IP-HAs were implanted into the right or left femoral condyle of rabbits (N= 10 in each group), and we performed histological examination, including enzymatic staining for osteoblasts and osteoclasts, three and six weeks after implantation. We observed improved bone ingrowth and increased osteoblast activity in polarized implants with complete bone penetration into polarized implants occurring as early as three weeks after surgery. In contrast, non-polarized implants were not fully ossified at six weeks after surgery. Furthermore, positively charged implant regions had decreased osteoclast activity compared to negatively charged or uncharged regions. We propose two different models to explain these observations.

Experiment 2.

We have developed a technology for electrical polarization and electrical characterization of HA micro-granule.HA micro-granules with or without electrical polarization were mixed with platelet-rich plasma (PRP) containing many growth factors, and implanted into femoral condyle of rabbits to compare osteoconductivity. As controls, HA micro-granules with or without electrical polarization, or PRP gel only was implanted. A model of bone hole only was made, as well (N= 6 in each group). Histological examination was performed six weeks after operation. New bone formation was enhanced by electrical polarization treatment in HA micro-granules. The application of PRP only could not induce new bone formation. In combination with HA with and without electrical polarization, however, PRP activated osteogenic cells, resulting in enhanced bone formation. It was confirmed that optimal resorption rate of biomaterials definitely exists to serve for a scaffold and electrical stimulator of osteogenic cells, and PRP can work as a good carrier of bioceramics micro-granules.