Osteoporosis primer for the vertebroplasty practitioner: expanding the focus beyond needles and cement

The effect of infliximab on bone healing in osteoporotic rats

Purpose:

The aim of this study was to evaluate the effect of the infliximab on autogenous-mediated bone regeneration and resorption of autogenous graft in the ovariectomised rat model.

Materials and methods:

Forty rats underwent ovariectomy and 6 weeks later the animals were randomly assigned to four groups. Critical size defects were created in each rat calvarium. In the control group (C), the flap was closed without any further action. In the only infliximab group (In), the flap was closed without any further action. After the operation, intravenous infliximab was injected. In the autogenous graft group (Ag), autogenous bone was applied in to the defect. In autogenous graft + infliximab group (Ag+In), autogenous graft was placed on the defect. After the operation, intravenous infliximab was injected. The animals were sacrificed at 4 weeks. Bone formation was assessed by micro-computed tomography (micro-CT) scans and stereological analysis.

Results:

The mean new bone volume was the greatest in Ag+In group (1.76 ± 0.20), followed by the Ag group (1.51 ± 0.05) (statistically significant difference at P <0.05). The lowest new bone was found in the control group (1.05 ± 0.09), however no difference was observed from the In group (1.14 ± 0.08) ( P >0.05). Besides there was a statistically significant difference between the Ag+In group (1.00 ± 0.05) and Ag group (0.74 ± 0.04) in terms of the graft volume ( P <0.05).

Conclusion:

This study, despite its limitations, showed that infliximab has a beneficial effect for prevent graft resorption and bone regeneration in osteoporotic rats.

Evaluation of the protective effects of curcuminoid (curcumin and bisdemethoxycurcumin)-loaded liposomes against bone turnover in a cell-based model of osteoarthritis

Curcumin (Cur) and bisdemethoxycurcumin (BDMC), extracted from Curcuma longa, are poorly water-soluble polyphenol compounds that have shown anti-inflammatory potential for the treatment of osteoarthritis. To increase cellular uptake of Cur and BDMC in bone tissue, soybean phosphatidylcholines were used for liposome formulation. In this study, curcuminoid (Cur and BDMC)-loaded liposomes were characterized in terms of particle size, encapsulation efficiency, liposome stability, and cellular uptake. The results show that there is about 70% entrapment efficiency of Cur and BDMC in liposomes and that particle sizes are stable after liposome formation. Both types of liposome can inhibit macrophage inflammation and osteoclast differential activities. In comparison with free drugs (Cur and BDMC), curcuminoid-loaded liposomes were less cytotoxic and expressed high cellular uptake of the drugs. Of note is that Cur-loaded liposomes can prevent liposome-dependent inhibition of osteoblast differentiation and mineralization, but BDMC-loaded liposomes could not. With interleukin (IL)-1β stimulation, curcuminoid-loaded liposomes can successfully downregulate the expression of inflammatory markers on osteoblasts, and show a high osteoprotegerin (OPG)/receptor activator of nuclear factor κB ligand (RANKL) ratio to prevent osteoclastogenesis. In the present study, we demonstrated that Cur and BDMC can be successfully encapsulated in liposomes and can reduce osteoclast activity and maintain osteoblast functions. Therefore, curcuminoid-loaded liposomes may slow osteoarthritis progression.

Asymptomatic and unrecognized cement pulmonary embolism commonly occurs with vertebroplasty

BACKGROUND AND PURPOSE

Cement PE represents a potentially serious complication following vertebroplasty. To determine the frequency and extent of cement PE during percutaneous vertebroplasty, we performed a retrospective review of chest CT scans obtained in patients who had previously undergone ≥1 vertebroplasty procedure.

MATERIALS AND METHODS

After approval by our local institutional review board, we retrospectively evaluated 244 patients who had undergone vertebroplasty at 465 levels and subsequently underwent chest CT. A thoracic radiologist evaluated the presence, number, size, and location of discrete cement PEs. We catalogued the following data: age, sex, number of treated vertebrae, cement volume per vertebra, operator, presence of cement leakage noted by the operator during the procedure, and clinical presentation at postvertebroplasty CT.

RESULTS

At least 1 cement PE was detected in 23 (9.4%; 95% CI, 6%-13%) of 244 patients; 1 patient was symptomatic from a cement PE. The mean number of discrete cement PEs was 3.2 ± 3.4 (median, 2; range, 1-12). There was no correlation among the total number of treatment sessions, number of levels treated per session, cement volume per level, operator, or time between vertebroplasty and chest CT in the detection of cement PE. Those with PE were significantly younger (P=.0229) and had significantly more total levels treated (P=.0260). Cement PE was recognized by the operator during the vertebroplasty in 2 (8.7%) of 23 patients found to have it on CT.

CONCLUSIONS

Small asymptomatic cement PEs are common during vertebroplasty and usually are not recognized by the operator during the procedure.

Recurrent pain after percutaneous vertebroplasty

OBJECTIVE

The purposes of this review are to summarize the causes of recurrent pain after percutaneous vertebroplasty and to discuss the incidence, clinical symptoms, risk factors, image findings, treatment and prognosis, and prevention of such pain.

CONCLUSION

Percutaneous vertebroplasty is widely used to treat patients with symptomatic osteoporotic compression fractures. Although the procedure relieves the pain of the compression fracture, recurrent back pain after percutaneous vertebroplasty is common.

Medical Therapy and Multilevel Vertebroplasty in Osteoporosis: When and Why

Vertebroplasty (VP) is a mini-invasive percutaneous technique for the treatment of symptomatic, vertebral body fracture (VBF) caused by porotic or other diseases and its outcome has now been demonstrated by many trials. Beyond the results of these trials on the efficacy and safety of VP, the real problem for patients with osteoporotic and non-osteoporotic vertebral fractures is the risk of new fractures to adjacent or distant vertebra following VP that is reported to range from 10% to 30%. It is still unclear whether this is related to the natural history of the underlying disease (osteoporotic and non-osteoporotic diseases) or to the treatment, especially when a single vertebral fracture in an osteoporotic patient is highly predictive of future fractures. To prevent new fractures to adjacent or distant vertebra following VP in porotic patients multiple non-pharmacologic interventions are recommended (diet with vitamin D or calcium supplements, smoking cessation, exercise) in addition to a specific medical therapy to block the activation of osteoclast cells responsible for bone resorption, and to re-establish correct bone remodeling. These drugs include anti-catabolic drugs: bisphosphonate, oestrogen hormone, and anabolic drugs: PTH analogues and strontium ranelate. Bisphosphonate are the most commonly used compounds to treat postmenopausal osteoporosis. However, medical treatment appears to be too slow to prevent the natural history of patients with VBF. One session multilevel VP could be performed to prevent vertebral refracture risk in porotic or non-porotic patients with recurrent VBFs also after the first VP even if there is not a true vertebral collapse. Even if there are no limits to how many body levels can be treated in one session, European and American guidelines suggest doing no more than three body levels in the same session to reduce patient discomfort, and to prevent peri-procedural anesthesiologic problems, like uncontrolled fat-embolism, cement leakage, and pulmonary embolism, that could be increased. How many vertebrae could be treated in same session could be analyzed beforehand based on MDCT vertebral morphology and trabecular structure, or on MRI-signal changes. Added to medical therapy, multilevel VP can be performed in selected cases to treat VBF related to osteoporosis, preventing fractures or refracture without any further thrombo-embolic or fat uncontrolled embolism peri or post-procedural complications.