Modified Pedicle Subtraction Osteotomy for Osteoporotic Vertebral Compression Fractures

Is Percutaneous Kyphoplasty the Better Choice for Treatment of Stage III Kümmell's Disease Without Neurological Symptoms? A Retrospective Study of Two Invasive Procedures

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

Kümmell's disease is an uncommon and complicated spinal condition first described in 1891. Treatment of this disease must be individualized according to the stage of disease and the experience and preference of the surgeon. Nevertheless, the surgical option in Stage III Kümmell's disease without neurological deficits remains controversial. The purpose of this study is to determine whether PKP or pedicle subtraction osteotomy (PSO) combined with long-segment fixation (LSF) is more effective in treating Kümmell's disease at Stage III without neurological impairments.

METHODS

Between January 2017 and June 2020, 89 patients were treated with PKP or PSO + LSF. The outcomes, including operative time, blood loss, Oswestry Disability Indexes (ODIs), heights of fractured vertebrae, visual analog scale (VAS) scores, and kyphosis Cobb angles, were measured at the follow-up time for the PKP group and PSO + LSF group. Fisher's exact test or chi-square test for number and percentage data was employed to compare statistical analyses between two groups.

RESULTS

Forty-six patients underwent PKP and 43 patients who treated by PSO + LSF. Postoperative measurements showed substantial improvements in kyphosis Cobb angle and vertebral height in the PKP group compared to preoperative measurements. Operating time, estimated blood loss, and duration of stay were all reduced in the PKP group compared to the PSO + LSF group. The PSO + LSF group had better correction of a kyphotic Cobb angle than the PKP group. Short-term monitoring showed that the PKP group had fewer ODI and VAS scores than the PSO + LSF group. In addition, no significant neurological symptoms were found after operation in both groups. The complication rates of PKP and PSO + LSF groups were 10.87% and 9.30%, respectively.

CONCLUSIONS

Kümmell's disease in Stage III without neurological symptoms responded to both PKP and PSO + LSF as safe and efficient treatments. Despite limited correction of kyphotic Cobb angle, PKP patients had better early clinical outcomes, increased fractured vertebral height, decreased blood loss, and less surgical trauma compared with the PSO + LSF group.

Biomechanical and clinical evaluation of PSO, modified PSO and VCR treating OVCF kyphosis: a finite element analysis

Objective

To confirm the effect of surgery on spinal column biomechanics and to provide theoretical support for the advantages and disadvantages of different surgical methods and their clinical efficacy.

Methods

33 continuous patients with no significant difference in risk factors related to the mechanical complications were enrolled in this retrospective study. Sagittal parameters were measured in the pre-, post-operative and following-up lateral radiograph of spine. An finite element (FE) model was created using CT scanning from a female volunteer with osteoporotic vertebral compression fracture (OVCF) with solely kyphosis. Pedicle subtraction osteotomy (PSO), vertebral column resection (VCR) and modified PSO(mPSO) for OVCF were simulated on FE model. Stress distribution and deformation of the FE model were measured.

Results

Clinical - All differences in preoperative spinal sagittal parameters were not statistically significant. mPSO showed it is superior to PSO and VCR in multiple postoperative and following-up spinal sagittal parameters. The operation duration and intraoperative blood loss of mPSO are less than the other two. For postoperative mechanical complications, no statistically significant differences were observed. Biomechanical - Six operating conditions (flexion, extension, left/right bending, left/right twisting) for each post-operative FE model have been examined. In most conditions, the displacement of mPSO is similar to that of PSO, with both larger than that of VCR. All the maximum equivalent stress on the vertebral body is within the safe range. The stress is mainly distributed on the T10 vertebral body and the fixed vertebral body L2, while the stress of VCR is greater than that of mPSO and PSO. The intervertebral disc pressure is highest in VCR, followed by PSO, and lowest in mPSO under all conditions. The maximum pressure on the intervertebral discs is located between T10 and T11.

Conclusion

The finite element analysis showed that mPSO has a similar spine stability to PSO, and possibly creates a better environment for bone-to-bone fusion and prevents adjacent segments degeneration. Combined with its less surgical risks, we believe that the modified pedicle subtraction osteotomy may be an appropriate strategy for indicated cases of OVCF.

Astaxanthin prevents bone loss in osteoporotic rats with palmitic acid through suppressing oxidative stress

OBJECTIVES

The study aimed to assess the role of Astaxanthin (ATX) in palmitic acid(PA) -induced bone loss in Ovariectomized(OVX) rats.

METHODS

In the OVX rat model, we observed that PA affects bone metabolism and accelerates bone loss. Additionally, treatment with ATX was able to suppress the deleterious effects of PA and a simultaneous decrease in serum MDA levels and an increase in SOD was observed.

RESULTS

In addition, rats treated with ATX were observed to have significantly increased bone mass and elevated activity of SIRT1 and SOD2 in bone tissue. When MC3T3-E1 and RAW264.7 cells induced osteoblast and osteoclast differentiation, the ATX intervention was able to significantly restore the restriction of osteogenic differentiation and the up-regulation of osteoclast differentiation with PA therapy. Furthermore, we confirm that PA damage to cells is caused by increased oxidative stress, and that ATX can target and modulate the activity of SIRT1 to regulate the levels of oxidative stress in cells.

CONCLUSION

Summarizing, ATX may inhibit PA-induced bone loss through its antioxidant properties via the SIRT1 signaling pathway.

[Translated article] Management of spinal deformities caused by osteoporotic vertebral fractures

Osteoporosis and fragility play a significant role in the treatment and planning of patients with deformity secondary to osteoporotic vertebral fracture (OVF). The resulting deformity can present significant challenges for its management, both from a medical and surgical perspective. The need for a specific classification for these deformities, including the potential for the development of artificial intelligence and machine learning in predictive analysis, is emerging as a key point in the coming years. Relevant aspects in preoperative optimisation and management of these patients are addressed. A classification with therapeutic guidance for the management of spinal deformity secondary to OVF is developed, emphasising the importance of personalised treatment. Flexibility and sagittal balance are considered key aspects. On the other hand, we recommend, especially with these fragile patients, management with minimally invasive techniques to promote rapid recovery and reduce the number of complications.

Management of Spinal Deformities Caused by Osteoporotic Vertebral Fractures

Osteoporosis and fragility play a significant role in the treatment and planning of patients with deformity secondary to osteoporotic vertebral fracture (OVF). The resulting deformity can present significant challenges for its management, both from a medical and surgical perspective. The need for a specific classification for these deformities, including the potential for the development of artificial intelligence and machine learning in predictive analysis, is emerging as a key point in the coming years. Relevant aspects in preoperative optimization and management of these patients are addressed. A classification with therapeutic guidance for the management of spinal deformity secondary to OVF is developed, emphasizing the importance of personalized treatment. Flexibility and sagittal balance are considered key aspects. On the other hand, we recommend, especially with these fragile patients, management with minimally invasive techniques to promote rapid recovery and reduce the number of complications.

Modified pedicle subtraction osteotomy for osteoporotic vertebral compression fractures: a retrospective study of 104 patients

BACKGROUND

Osteoporotic vertebral compression fractures (OVCF) caused by osteoporosis is a common clinical fracture type. There are many surgical treatment options for OVCF, but there is a lack of comparison among different options. Therefore, we counted a total of 104 cases of OVCF operations with different surgical plans, followed up the patients, and compared the surgical outcome indications before, after and during the follow-up.

METHOD

104 patients who underwent posterior osteotomy (Modified PSO, SPO, PSO, VCR) and kyphosis correction surgery at our hospital between April 2006 and August 2021 with a minimum follow-up period of 24 months were included. All cases were injuries induced by a fall incurred while standing or lifting heavy objects without high-energy trauma. The mean CT value was 71 HU, which was below 110 HU, indicating severe osteoporosis. The indications for surgery included gait disturbance due to severe pain with pseudarthrosis, increased kyphotic angle, and progressive neurological symptoms. Pre- and postoperative CL, TLK, TK, PrTK, TKmax, GK, LL, PI, SS, PT, SVA, TPA, were investigated radiologically. Additionally, We evaluated estimated blood loss, surgical time and perioperative symptom.

RESULT

The results show, after operation, TLK (37.32 ± 10.61° vs. 11.01 ± 8.06°, P < 0.001), TK (35.42 ± 17.64° vs. 25.62 ± 12.24°, P < 0.001), TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001), SVA (44.91 ± 48.67 vs. 23.52 ± 30.21, P = 0.013), CL (20.23 ± 13.21° vs. 11.45 ± 9.85°, P = 0.024) and TPA (27.44 ± 12.76° vs. 13.91 ± 9.24°, P = 0.009) were improved significantly in modified Pedicle subtraction osteotomy (mPSO) after operation. During follow-up, TLK (37.32 ± 10.61° vs. 13.88 ± 10.02°, P < 0.001) and TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001) were improved significantly in Modified PSO group. In additon, estimated blood loss (790.0 ± 552.2 ml vs. 987.0 ± 638.5 ml, P = 0.038), time of operation (244.1 ± 63.0 min vs. 292.4 ± 87.6 min, P = 0.025) were favorable in Modified PSO group compared to control group.

CONCLUSION

To conclude, mPSO could acquire a favorable degree of kyphosis correction as well as fewer follow-up complications. Compared with other surgical methods, it also has the advantages of less surgical trauma and shorter operation time. It can be an effective solution for the treatment of OVCF.

Treatment Strategies in the Osteoporotic Spine

This article reviews the appropriate assessment and management of osteoporotic compression fractures and discusses the implications of osteoporosis on initial patient evaluation, medical optimization for surgery, selection of instrumentation, and surgical technique. Adverse outcomes associated with osteoporosis are discussed. Failure to appropriately evaluate, optimize, and treat spine patients with osteoporotic bone can lead to disastrous complications. Weakened bone can lead to implant failure through cage subsidence and screw pullout, as well as, peri-implant fractures, failure of deformity correction, and proximal kyphosis. These risks must be taken into account when considering operative interventions in these patients.

Finite element study on three osteotomy methods for treating thoracolumbar osteoporotic fracture vertebral collapse complicated with neurological dysfunction

BACKGROUND

Surgical methods for patients with osteoporotic fracture vertebral collapse complicated with neurological dysfunction are still a topic of debate. We designed an improved osteotomy for the treatment of osteoporotic compression fracture patients with neurological dysfunction. Compared with traditional osteotomy methods such as pedicle subtraction osteotomy (PSO) and bone-disc-bone osteotomy (BDBO), the osteotomy range is reduced. Therefore, we use a finite element method to analyze the biomechanical conditions of these three osteotomy methods and provide a mechanical theoretical basis for the surgical treatment of these three osteotomy methods.

METHODS

Based on the CT scan of a patient with L1 osteoporotic fracture vertebral collapse and neurological dysfunction, the finite element model was constructed by importing Mimics software, and three different osteotomy models were established. The forces and displacements of internal fixation device, T1-L5 whole segment, T10 vertebral body, and T10/11 intervertebral disc were recorded under different working conditions.

RESULTS

The displacement levels of internal fixation device, T1-L5 spine, T10 vertebral body, and T10/11 intervertebral disc in the modified osteotomy group were between BDBO group and PSO group. The stress in BDBO group was concentrated in titanium mesh and its maximum stress was much higher than that in PSO group and modified osteotomy group. The mechanical distribution of T10/11 intervertebral disc showed that the maximum stress distribution of the three osteotomy methods was similar.

CONCLUSION

The relatively simple modified osteotomy has certain advantages in stress and displacement. In contrast, the stability of BDBO group was poor, especially in the lumbar intervertebral disc and lumbar body. For this type of osteotomy patients, it is recommended to avoid postoperative flexion so as not to increase the load.

Open Surgical Treatments of Osteoporotic Vertebral Compression Fractures

With an aging population, the osteoporotic vertebral compression fracture (OVCF) has become a constant concern for its physical and neurological complications, such as spinal kyphosis and refractory pains. Compared with traditional conservative treatments, the open surgery is more superior in some ways because of its direct decompression and correction. Various operation methods applying to different indications have been developed to deal with different fracture situations, including anterior, posterior, and combined surgery. In this review, we have concluded the latest developments of the surgery treating OVCF and the internal fixation as references for spinal surgeons of the choice of suitable treatments.

Modified posterior osteotomy for osteoporotic vertebral collapse with neurological dysfunction in thoracolumbar spine: a preliminary study

OBJECTIVE

The risk of osteoporotic vertebral collapse (OVC) associated with delayed neurological dysfunction (DND) is substantial, and performing surgery for this condition in elderly patients presents challenges. The focus of the current research is on simplifying surgical procedures while maintaining their effectiveness. This study was designed to contribute clinical data supporting the use of modified posterior osteotomy for treating thoracolumbar OVC with DND. The study compares perioperative clinical parameters, imaging data characteristics, and changes in efficacy outcome indicators to provide evidence for the advancement of this technique.

METHODS

A total of 12 patients diagnosed with osteoporotic vertebral collapse and neurological dysfunction were included in the study. All patients underwent modified posterior osteotomy. Data regarding perioperative and radiological parameters as well as complications such as surgery duration, blood loss, ASIA grade, VAS, ODI, regional kyphosis angle (RKA), anterior vertebral height ratio (AVHr), and spinal canal clearance ratio (SCCr), were collected retrospectively. These parameters were then analysed to evaluate the clinical efficacy and safety of the modified posterior osteotomy technique.

RESULTS

A total of 12 patients were included in the study, with a mean age of 65.5 ± 9.7 years. The average follow-up period was 29.4 ± 5.0 months. The mean operative blood loss was 483.3 ± 142.0 ml, and the average operative time was 3.7 ± 0.7 h. The visual analogue scale (VAS) score decreased from a preoperative value of 5.8 ± 0.7 to a final follow-up value of 1.3 ± 0.8 (P < 0.05), indicating a significant improvement in pain. The ODI decreased from 65.2 ± 6.0 before surgery to 20.5 ± 7.0, indicating a decrease in disability, and the postoperative neurological function showed a significant improvement. Correction of the RKA was observed, with the angle changing from 35.8 ± 10.8° before surgery to 20.0 ± 3.5° after surgery and to 22.5 ± 3.1° at the final follow-up. Similarly, correction of the AVHr was observed, with the height changing from 39.3 ± 18.0 to 63.0 ± 14.3 after surgery and to 53.9 ± 8.9 at the final follow-up. Correction of the SCCr was also observed, with the ratio changing from 54.9 ± 5.4 to 68.1 ± 5.3 after surgery and to 68.68 ± 6.76 at the final follow-up.

CONCLUSIONS

Posterior modified osteotomy is an effective treatment for thoracolumbar osteoporotic fractures with OVC combined with DND. It can significantly preserve vertebral height, increase vertebral canal volume, correct kyphotic angle, and improve postoperative neurological function. The simplified osteotomy also offers advantages in terms of operating time, blood loss, postoperative VAS score, and improvement in lumbar function.

Differences in surgical outcome after anterior corpectomy and reconstruction with an expandable cage with rectangular footplates between thoracolumbar and lumbar osteoporotic vertebral fracture

Background

Anterior and posterior spinal fixation (APSF) can provide rigid structural anterior column support in patients with osteoporotic vertebral fracture (OVF). A new rectangular footplate designed based on biomechanical studies of endplates provides better resistance to subsidence. However, differences in characteristics exist between the thoracolumbar and lower lumbar spine. The purpose of this study was to evaluate the surgical outcomes following APSF using an expandable cage with rectangular footplates in the thoracolumbar/lumbar region.

Methods

Consecutive patients who underwent APSF for OVF at multiple centers were retrospectively reviewed. Clinical and radiographic evaluations were performed by dividing the patients into thoracolumbar (TL, T10–L2) and lumbar (L, L3–L5) groups. Surgical indications were incomplete neurologic deficit or intractable back pain with segmental spinal instability. Surgical outcomes including the Japanese Orthopaedic Association (JOA) score and reoperation rate were compared between TL and L groups.

Results

Sixty-nine patients were followed-up for more than 12 months and analyzed. Operative intervention was required for 35 patients in the TL group and 34 patients in the L group. Mean ages in the TL and L groups were 76.5 years and 75.1 years, respectively. Intra-vertebral instability was more frequent in the TL group (p<0.001). Screw fixation range was significantly longer in the TL group (p=0.012). The rate of cage subsidence did not differ significantly between the TL group (46%) and L group (44%). Reoperation rate tended to be higher in the TL group (p=0.095). Improvement ratio of JOA score was significantly better in the L group (60%) than in the TL group (46.9%, p=0.029).

Conclusion

APSF using an expandable cage was effective to treat OVF at both lumbar and thoracolumbar levels. However, the improvement ratio of the JOA score was better in the L group than in the TL group.