Kümmell's Disease: Clarifying the Mechanisms and Patients' Inclusion Criteria

Comparison of the Clinical Outcomes of Vesselplasty vs. Percutaneous Vertebroplasty for the Treatment of Neurologically Intact Osteoporotic Kümmell's Disease: A Retrospective Study

Kummell's disease (KD) is a rare clinical complication of osteoporotic vertebral compression fractures (OVCFs). Minimally invasive surgery is an important way to treat KD. In this paper, we used Percutaneous Vertebroplasty (PVP) and Vesselplasty (VP) to treat KD. 125 patients with KD were admitted to our hospital. Among them, 89 patients received PVP and 36 received VP. All patients underwent operations successfully. VAS scores and ODI of both groups at each postoperative time point were lower than preoperatively. Postoperative Cobb angle of both groups postoperatively was lower than preoperatively (p < 0.05). The anterior height and ratio of vertebra compression of both groups postoperatively was lower than preoperatively (p < 0.05). Cement leakage occurred in 16 vertebrae (16/89) in PVP group and one (1/36) in VP group. Two patients suffered from transient paraplegia in PVP group immediately after operation. Adjacent vertebral fractures occurred in one patient in PVP group and one in VP group. Re-fracture of affected vertebra occurred in one patient in PVP group. Besides, four patients suffered from bone cement loosening in PVP group while one in VP group. Both PVP and VP play an important effect in pain relief and functional recovery for the treatment of KD. And VP is more effective than PVP in preventing cement leakage.

Treatment of kyphotic deformity in Kümmell's disease through vertebral body screw fixation and intertransverse process grafting: A case report

RATIONALE

Kümmell's disease, also well acknowledged as delayed posttraumatic vertebral body collapse, it is a rare condition which mainly occurs in elderly people more than 50 years old, with the thoracolumbar junction being mostly affected.

PATIENT CONCERNS

In this research, we employed posterior short-segment screw fixation within the injured vertebral region, coupled with intertransverse process bone grafting, to address Kümmell's disease. A 57-year-old female was admitted to our institution with incapacitating back pain and obvious kyphotic deformity.

DIAGNOSES

The diagnosis of Kummell disease was mainly depended on clinical symptoms and imaging examinations.

INTERVENTIONS

In this research, we employed posterior short-segment screw fixation within the injured vertebral region, coupled with intertransverse process bone grafting, to address Kümmell's disease.

OUTCOMES

The patient could walk independently with the help of a thoracolumbosacral orthosis brace on postoperative Day 2. No pains, kyphotic deformity and neurological deficits were observed during the 36 months of postoperative follow-up. These improvements can be visualized through postoperative magnetic resonance imaging and CT scans. Short-segment screw fixation provides short-term stability to the fracture site and accelerates fracture healing. Subsequently, the healed intervertebral and transverse process grafts offer long-term stability, a fact corroborated by postoperative CT scans.

LESSONS

In summary, for Kümmell's disease patients exhibiting kyphotic deformity without neurological deficits or compression, posterior short-segment vertebral screw fixation with intertransverse process bone grafting stands as a viable alternative treatment approach.

Comparison between percutaneous short-segment fixation and percutaneous vertebroplasty in treating Kummell's disease: A minimum 2-year follow-up retrospective study

BACKGROUND

Percutaneous kyphoplasty (PKP) or percutaneous short-segment fixation (PSSF) is often used to treat Kummell's disease. However, it is not clear which treatment is better for patients.

OBJECTIVE

To retrospectively compare the clinical efficacy of PVP and PSSF for the treatment of Kummell's disease.

METHOD

60 patients were involved in this research and the period of follow-up was at least 2 years. 27 of them were treated with PVP (Group I) and the rest who received PSSF (Group II). The visual analog scale (VAS) and radiographic indexes of each participant had been measured preoperatively as well as 1 week, 3 months, and 2 years postoperatively. Additionally, the Oswestry Disability Index (ODI) scores were assessed at the last time point.

RESULTS

Comparing the two groups, no statistical significance was found among all parameters preoperatively. The time of operations and blood loss is less in Group I. At each time point after operation, the imaging indices in Group II are lower (P< 0.05). One week after treatments, the VAS scores are lower in Group I, and similarly, 3 months are the same (P< 0.05), while VAS are similar at the last time point. In the aspect of ODI scores, they are lower in Group II during long-term follow-up.

CONCLUSION

For the treatment of Kummell's disease, both PVP and PSSF have been found to be effective. PVP can provide rapid pain relief with a shorter operation time. However, in cases with severe kyphosis deformity, PSSF should be given priority.

Intravertebral insertion of interbody fusion cage via transpedicular approach for the treatment of stage III Kümmell disease: a technical note and case presentation

BACKGROUND

Kümmell disease usually occurs in the elderly osteoporosis population and develops gradually into symptomatic, progressive kyphosis of the spine. However, current surgical methods to deal with stage III Kümmell disease are less satisfying. The objective of this study was to describe a less invasive technique for treating stage III Kümmell disease.

TECHNIQUE

A less invasive technique of intravertebral insertion of interbody fusion cage via transpedicular approach with posterior spine stabilization was applied to treat stage III Kümmell disease.

RESULTS

This study details a modified technique applied in a patient with stage III Kümmell disease, showing significant improvement in pain relief, anterior column height recovery, and kyphotic angle correction. And no complications were reported during our follow-up.

CONCLUSIONS

Intravertebral insertion of interbody fusion cage via transpedicular approach provides advantages of acceptable correction of kyphosis, bony fusion, minimal invasion. Thus, our method was a good alternative choice for stage III Kümmell disease.

Double Vertebrae Kümmell Disease: Five Cases Report and Literature Review

Kümmell disease (KD) is a complication of osteoporotic vertebral compression fractures. There is a lot of literature on KD, but the reported cases are all single vertebrae. This study reports five double vertebrae KD cases (10 levels) and discusses the possible underlying mechanisms with a literature review. One hundred and thirty vertebrae KD were diagnosed from 2074 osteoporotic vertebral compression fractures patients treated in our hospital between 2015 and 2019. These vertebrae KD were divided into two groups, one-level vertebrae KD (n = 125) and double-level KD (n = 5). The diagnosis of KD is mainly based on the signs of intravertebral vacuum cleft on X-ray or CT scan. Double vertebrae KD cases were classified by using the KD staging system. The analysis was performed on KD to compare age, gender, femoral neck bone mineral density of femoral neck (BMD), vertebrae distribution, Cobb angle, and visual analog scale (VAS) between one-level KD and double-level by t-tests, Welch's t-test, or hypothesis testing. The mean age of the participants in the one-level KD group was 78.69 years, while the mean age in the double-level KD group was 82.4 years. The difference was statistically significant (t = 3.66, p = 0.0004). There were 89 females and 36 males in the one-level KD group, while the double-level KD group had five females and no males. The femoral neck BMD was significantly different between the two groups, with the one-level KD group having a mean BMD of -2.75 and the double-level KD group having a mean BMD of -4.2 (t = 2.99, p= 0.0061). The vertebrae distribution was different between the groups, with the one-level KD group having vertebrae from T7 to L4 and the double-level KD group having vertebrae from T11 to L1. The Cobb angle was also significantly different between the groups, with the one-level KD group having a mean angle of 20.58 and the double-level KD group having a mean angle of 31.54 (t = 6.22, p = 0.0001). Finally, the VAS scores were similar between the two groups, with the one-level KD group having a mean score of 8.63 and the double-level KD group having a mean score of 8.8 (t = 1.35, p = 0.1790). It is concluded that double vertebrae Kümmell disease has special clinical significance due to its potential to cause greater spinal instability and deformity, increased risk of neurological symptoms, more complex surgical management, and greater risk of complications.

A mid- and long-term follow-up study on the bilateral pedicle anchoring technique with percutaneous vertebroplasty for the treatment of Kümmell's disease

Study design

Retrospective study of clinical and radiological parameters.

Objective

To investigate the clinical efficacy and long-term stability of bone cement of the bilateral pedicle anchoring technique with percutaneous vertebroplasty (PVP) in the treatment of Kümmell's disease (KD).

Summary of background data

The optimal treatment regimen for KD remains controversial. With the development of minimally invasive orthopedic techniques, PVP has been widely recognized for its advantages, such as less surgical trauma, shorter operation time, less blood loss, quick recovery, and pain relief. Previous reports indicate that in patients who undergo PVP for KD, bone cement may be displaced, causing pain recurrence, or it may enter the spinal canal and cause spinal cord compression, especially in the long term. Theoretically, the bilateral pedicle anchoring technique can enhance the stability of the bone cement in the vertebral body and reduce the occurrence of long-term bone cement displacement. However, there are few reports on the use of this technique to treat KD. This study reports the mid- and long-term follow-up of the clinical and radiological outcomes of the bilateral pedicle anchoring technique with PVP for the treatment of KD.

Methods

From January 2016 to January 2019, 41 patients with KD treated using the bilateral pedicle anchoring technique with PVP in our hospital were enrolled. There were 10 men and 31 women with an average age of 76.5 ± 8.0 years (range: 55-92 years). The average follow-up duration was 19.3 ± 8.0 months (range: 12-38 months). Visual analog scale (VAS) scores, Oswestry disability index (ODI), anterior vertebral height, kyphotic angle, and wedge angle were recorded before surgery, 1 day after surgery, and at the last follow-up. Clinical efficacy, vertebral height recovery, and bone cement displacement were analyzed in combination using plain radiographs, computed tomography, magnetic resonance imaging, and other imaging data.

Results

All the patients successfully underwent the procedure without serious complications. No obvious displacement of bone cement was found in the imaging data obtained 1 day after the operation and at the last follow-up. VAS scores, ODI scores, anterior vertebral height, kyphotic angle, and wedge angle of the injured vertebrae significantly improved after surgery. There was no significant difference between the anterior vertebral height, kyphotic angle, and wedge angle of the vertebral body obtained 1 day after surgery and those obtained at the last follow-up. Bone cement leakage occurred in seven patients, with no abnormal clinical symptoms.

Conclusion

The bilateral pedicle anchoring technique with PVP integrates the use of bone cement in both the vertebral body and the bone cement in the pedicle, enhances the stability of the bone cement, and effectively prevents the displacement of the intravertebral bone cement. The postoperative bone cement stability was high, the clinical effect was obvious, and the long-term follow-up results were satisfactory. Hence, this is a safe and effective surgical method for the treatment of KD.

Current status and challenges of percutaneous vertebroplasty (PVP)

A narrative review regarding percutaneous vertebroplasty (PVP) for osteoporotic vertebral fracture (OVF) is provided herein, addressing the epidemic of OVF in Japan, the latest response to the criticism of PVP for OVFs, the indications and potential risks of PVP for OVFs, and a future perspective for PVP. Each year in Japan, approximately 32,000 patients aged 55 years or older suffer from chronic low back pain for several months to several years due to a compression fracture. PVP is one of the surgical treatments for an OVF, and it is less invasive compared to the traditional open surgery. PVP is suitable for OVF patients who have difficulty walking as assessed by the modified Yokoyama's activities of daily living (ADL) scoring system, and for patients with Kummell's disease diagnosed by CT and MRI examinations. Serious adverse events related to PVP occur in 1.1-3.3% of the cases, but direct deaths from PVP are extremely rare at less than 1%. Recent studies demonstrated that OVF patients treated with PVP are less likely to die after the treatment than non-surgically treated patients, which conflicts with the Cochran reviews' conclusion not supporting PVP for OVFs. Novel robotic systems and procedure-support devices are being developed, providing a next step toward fully automated PVP procedures.

Strategies in the Management of Osteoporotic Kummell's Disease

Introduction

Kummell disease is a condition characterized by severe pain, progressing kyphosis with or without neurological deficit following a trivial trauma in the old age osteoporotic population. It is an osteoporotic vertebral fracture due to avascular necrosis of the vertebra, having an asymptomatic period initially followed by progressive pain, kyphosis, and neurologic deficit. Although various management options are available for Kummell's disease, a dilemma occurs in selecting an optimal modality in each case.

Case Report

A 65-year-old female presented with complaints of low back pain for 4 weeks. She developed progressive weakness and bowel bladder disturbance. Radiographs showed a D12 vertebral compression fracture with an intravertebral vacuum cleft sign. Magnetic resonance imaging showed intravertebral fluid and significant compression of the cord. We performed posterior decompression, stabilization, and transpedicular bone grafting at the D12 level. Histopathology confirmed Kummell's disease. The patient recovered with restored power and bladder control and resumed independent ambulation.

Conclusion

Osteoporotic compression fractures are more prone to pseudoarthrosis due to poor vascular and mechanical support, they need adequate immobilization and bracing. Transpedicular bone grafting for kummels disease seems to be a good surgical option due to its short operating time, less bleeding, less invasive approach, and early recovery. However, a treatment-oriented classification is needed to treat this clinical entity on a case-by-case basis.

Comparison between Percutaneous Kyphoplasty and Posterior Fixation Combined with Vertebroplasty in the Treatment of Stage III Kümmell’s Disease without Neurological Deficit

Objective. To evaluate the clinical and radiological outcomes of percutaneous kyphoplasty (PKP) versus posterior fixation combined with vertebroplasty PF+VP for treating stage III Kümmell’s disease (KD) patients without neurological deficits. Methods. From April 2016 to February 2020, a total of 88 patients with single-level stage III KD without neurological deficits, including 45 patients treated by PKP and 43 patients who underwent posterior fixation combined with vertebroplasty PF+VP, were retrospectively studied. The outcome parameters, including blood loss, operative time, kyphotic Cobb angle, height of vertebrae, Oswestry Disability Index (ODI), and visual analog scale (VAS) score, were compared between the PKP group and the PF+VP group. Results. The mean follow-up time was $29.3\pm 7.0$ months, ranging from 24 to 48 months. The kyphotic angle and vertebral height in both groups were significantly improved compared with those before surgery at three days, 3 months and the final follow-up. The estimated blood loss, operative time, and length of stay were significantly lower in the PKP group than in the PF+VP group ( $P<0.001$ ). The FP+VP group showed better results in kyphotic angle correction than the PKP group ( $P=0.024$ ). In the short-term follow-up (up to 3 months), the PKP group had lower VAS and ODI scores than the PF+VP group. In contrast, there were no significant differences between the two groups ( $P>0.05$ ) at the final follow-up. The average cost of PKP was lower than that of PF+VP. Conclusion. The results of our study showed that both PKP and PF+VP were safe and effective for stage III KD patients without neurological deficits. Although PF+VP presents better performance in kyphotic angle correction, PKP was associated with less surgical trauma, quicker pain relief, and lower expense than PF+VP. Therefore, it can be considered an alternative option for patients with advanced KD.

The value of magnetic resonance imaging and computed tomography in the study of spinal disorders

Computed tomography (CT) and magnetic resonance imaging (MRI) have replaced conventional radiography in the study of many spinal conditions, it is essential to know when these techniques are indicated instead of or as complementary tests to radiography, which findings can be expected in different clinical settings, and their significance in the diagnosis of different spinal conditions. Proper use of CT and MRI in spinal disorders may facilitate diagnosis and management of spinal conditions. An adequate clinical approach, a good understanding of the pathological manifestations demonstrated by these imaging techniques and a comprehensive report based on a universally accepted nomenclature represent the indispensable tools to improve the diagnostic approach and the decision-making process in patients with spinal pain. Several guidelines are available to assist clinicians in ordering appropriate imaging techniques to achieve an accurate diagnosis and to ensure appropriate medical care that meets the efficacy and safety needs of patients. This article reviews the clinical indications of CT and MRI in different pathologic conditions affecting the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumor disorders, as well as their main imaging features. It is intended to be a pictorial guide to clinicians involved in the diagnosis and treatment of spinal disorders.

Bone microarchitecture and metabolism in elderly male patients with signs of intravertebral cleft on MRI

OBJECTIVES

Intravertebral cleft (IVC) is a common but not unique imaging manifestation in Kümmell's disease. To date, great controversy exists regarding the specific mechanisms of IVC. In this study, we aimed to investigate the characteristics of microarchitecture and metabolism in patients with IVC and to analyse the correlations between degree of vertebral collapse and risk factors.

METHODS

A total of 79 elderly men were included in this study. We divided all patients into two groups: the IVC group (30 patients) and the non-IVC group (49 patients). We compared the differences in microarchitecture and bone turnover marker (BTM) serum concentrations between the groups and analysed risk factors affecting vertebral collapse by using the Mann-Whitney U test and Spearman's correlation test.

RESULTS

Quantitative analysis of the microarchitecture showed higher content of necrotic bone (p < 0.001) and lower content of lamellar bone (p < 0.001) in the IVC group. Analysis of BTMs identified lower concentration of N-terminal propeptide of type I collagen (PINP, p = 0.002) and higher concentration of β-isomerized C-terminal telopeptide (β-CTX, p < 0.001) in the IVC group. The correlation analysis showed that lamellar bone content (p < 0.001) and spine T-score (p = 0.011) were significantly correlated with the degree of vertebral collapse.

CONCLUSIONS

IVC is a radiological feature of excessive bone resorption by higher activities of osteoclasts and decreased bone remodelling ability by lower activities of osteoblasts. Histomorphological feature in patients with IVC is delayed callus mineralisation, which may increase the risk of vertebral collapse.

KEY POINTS

• A key histomorphological feature in patients with IVC is delayed callus mineralisation, which may aggravate the degree of vertebral collapse. • We investigated bone metabolism in patients with IVC to evaluate the activities of osteoclasts and osteoblasts directly. • We propose a novel hypothesis for the pathogenesis of IVC: bone resorption by higher activity of osteoclasts and decreased callus mineralisation ability by lower activity of osteoblasts are the main mechanisms leading to IVC.

Revisiting Kümmell's disease: MRI findings beyond the intraosseous cavity for improved diagnosis

PURPOSE

The diagnostic tool for Kümmell's disease (KD), including the intravertebral vacuum cavity on imaging, is still limited. The purpose of this study was to find other magnetic resonance imaging (MRI) findings that could help the diagnosis of KD.

METHODS

A total of 289 patients (103 males and 186 females with a mean age of 69 ± 15 years) with thoracolumbar compression fracture were included. Medical records were reviewed to note symptom duration. MRIs were analyzed for intraosseous cavities (IOC), prevertebral soft-tissue changes (PreSC), posterior wall fracture (PoF), and posterior ligamentous complex tear (PLCT). KD was diagnosed based on surgical findings or clinical report. MRI findings and symptom duration in the presence or absence of KD were compared with chi-squared test, logistic regression, and Student's t-test and area under the curve (AUC) analyses.

RESULTS

KD was diagnosed in 55 cases. IOC was noted in 33 (60%) cases in the KD group and 82 (35%) cases in non-KD group. Definite PreSC was noted in 44 (80%) cases in the KD group and 94 (40%) cases in the non-KD group. PoF was seen in 36 (65%) and 140 (60%) cases, and PLCT was seen in 7 (13%) and 26 (11%) cases in KD and non-KD groups, respectively. The IOC and PreSC MRI findings were significantly correlated with KD (p < 0.001), but not with PoF (p = 0.539) or PLCT (p = 0.814). AUC of combined IOC and PreSC was 0.72, higher than that of IOC alone (0.63) or PreSC alone (0.69) (both p < 0.001). The average duration of symptom was 64 days in the KD group and 14 days in the non-KD group (p < 0.001). Positive IOC and PreSC findings were associated with longer symptom duration (p < 0.001).

CONCLUSIONS

Prevertebral soft-tissue changes and intraosseous cavity are associated with KD. Combined findings of prevertebral soft-tissue changes and intraosseous cavity can help the diagnosis of KD.

Treatment of Kümmell’s disease following the occurrence of osteoporotic vertebral compression fracture

Background: The incidence of osteoporotic vertebral compression fracture (OVCF) is increasing with the increase in the elderly population. Kümmell’s disease following OVCF occurrence is not a rare complication and is frequently associated with severe pain or neurologic deficit with progressive kyphotic deformity. Kümmell’s disease initially meant post-traumatic delayed vertebral collapse, but now it is also termed nonunion, osteonecrosis, or intravertebral vacuum cleft, all of which suggest the disruption of the healing process.Current Concepts: The major pathogenesis of Kümmell’s disease is a vascular compromise caused by mechanical stress or intravascular pathology. The key radiologic sign to diagnose Kümmell’s disease is the presence of intravertebral vacuum cleft, observed using simple X-ray, computed tomography, or magnetic resonance imaging. Magnetic resonance imaging is the most useful diagnostic tool showing gas or fluid signals. The risk factors for the progression of Kümmell’s disease after OVCF include middle-column injury, confined low signal intensity on T2-weighted image, posterior wall combined fracture, kyphotic angle >10°, and a height loss >15%. Its treatment can be broadly classified as conservative treatment, bone cement injection, and surgical treatment. The appropriate treatment method is selected based on the pain intensity, neurological symptoms, and the severity of the kyphotic deformity.Discussion and Conclusion: Kümmell’s disease usually develops along with osteoporosis. Therefore, the treatment should be focused on relief from symptoms associated with Kümmell’s disease and osteoporosis. It is recommended that an anabolic agent should be administered after the diagnosis of Kümmell’s disease, regardless of the treatment modality.

Back Pain Due to Kummell's Disease

Kummell’s disease (KD) is a delayed post-traumatic avascular osteonecrosis of the vertebral body secondary to a vertebral compression fracture that can present with back pain. We discuss the importance of an accurate diagnosis and appropriate management of Kummell’s disease. Additionally, we aim to increase awareness and promote early diagnosis and treatment to prevent serious complications.

A 55-year-old man had been diagnosed with avascular necrosis (AVN) of both hips and had a history of trauma to the left hip ten years ago. Between the initial fall and subsequent presentation, he resumed independent physical activity. At approximately 10 months following his initial injury, he returned to a local emergency department with vague complaints of lower back pain. He was prescribed analgesics for pain and discharged. Subsequently, he experienced a progressive increase in pain and complained of motor deficits of the lower limbs. He presented to our emergency room with acute onset of worsening pain. Magnetic resonance imaging revealed multiple-level compression fractures and a fluid cleft in the L2 intervertebral disc. Surgery was advised, but he did not consent. Therefore, nonsurgical treatment included bed rest, wearing a brace, lumbar traction, analgesics, and medication to prevent osteoporosis.

Prompt, accurate diagnosis of Kummell’s disease is important for timely, appropriate treatment, which can improve quality of life and prevent comorbidities.

Vertebral augmentation plus short-segment fixation versus vertebral augmentation alone in Kümmell's disease: a systematic review and meta-analysis

Osteoporotic vertebral compression fractures of the thoracolumbar spine can progress to Kümmell's disease, an avascular vertebral osteonecrosis. Vertebral augmentation (VA)-vertebroplasty and/or kyphoplasty-is the main treatment modality, but additional short-segment fixation (SSF) has been recommended concomitant to VA. The aim is to compare clinical and radiological outcomes of VA + SSF versus VA alone. Systematic review, including comparative articles in Kümmell's disease, was performed. This study assessed the following outcome measurements: visual analog scale (VAS), Oswestry Disability Index (ODI), anterior vertebral height (AVH), local kyphotic angle (LKA), operative time, blood loss, length of stay, and cement leakage. Six retrospective studies were included, with 126 patients in the VA + SSF group and 152 in VA alone. Pooled analysis showed the following: VAS, non-significant difference favoring VA + SSF: MD -0.61, 95% CI (-1.44, 0.23), I² 91%, p = 0.15; ODI, non-significant difference favoring VA + SSF: MD -9.85, 95% CI (-19.63, -0.07), I² 96%, p = 0.05; AVH, VA + SSF had a non-significant difference over VA alone: MD -3.21 mm, 95% CI (-7.55, 1.14), I² 92%, p = 0.15; LKA, non-significant difference favoring VA + SSF: MD -0.85°, 95% CI (-5.10, 3.40), I² 95%, p = 0.70. There were higher operative time, blood loss, and hospital length of stay for VA + SSF (p < 0.05), but with lower cement leakage (p < 0.05). VA + SFF and VA alone are effective treatment modalities in Kümmell's disease. VA + SSF may provide superior long-term results in clinical and radiological outcomes but required a longer length of stay.

Vertebral Collapse Prevented Following Teriparatide Treatment in Postmenopausal Kümmell's Disease Patients with Severe Osteoporosis

OBJECTIVE

To compare the preventive effects of teriparatide and alendronate on the progression of vertebral body collapse in postmenopausal single-level Kümmell's disease (KD).

METHODS

From March 2013 to December 2020, the medical records for 53 postmenopausal single-level KD patients who received conservative treatment with teriparatide (25 patients, teriparatide group) or alendronate (28 patients, alendronate group) were retrospectively reviewed. Midsagittal computed tomography (CT) images were analyzed by ImageJ to assess the intravertebral bone formation (mineralized bone) by calculating the ratio of area of intravertebral mineralized bone (AIMB) to the area of fractured vertebral body (AFVB). The changes in radiological parameters of the fractured vertebral body including kyphosis angle (KA), anterior and posterior border heights (ABH and PBH) and spinal canal diameter (SCD), bone turnover biomarkers (BTMs), and bone mineral density (BMD) were analyzed to evaluate the therapeutic effect.

RESULTS

At month 12, the ratio of AIMB to AFVB was significantly greater in teriparatide group (54.28% ± 15.30%) than in alendronate group (35.57% ± 17.61%) (P < 0.001). Sagittal CT substantiated the formation of bone bridge in 16 patients in teriparatide group. No bone bridge was detected in alendronate group. The KA was significantly smaller and the ABH, PBH, and SCD was greater in teriparatide group than in alendronate group (all P < 0.001). The KA increments were significantly smaller in teriparatide group (3.98° ± 1.30°) than in alendronate group (11.43° ± 3.73°) (P < 0.001). The ABH and PBH decrement were significantly lower in teriparatide group (11.96% ± 1.93% and 2.80% ± 2.52%) than in alendronate group (37.04% ± 8.00% and 19.50% ± 8.22%) (both P < 0.001). The BTMs and BMD were significantly greater in the teriparatide group than in the alendronate group. In teriparatide group, KA increment was negatively correlated with the change in PINP (r = -0.781, P < 0.001) and the ratio of AIMB to AFVB (r = -0.592, P = 0.002) from baseline to month 12. The ABH decrement was negatively correlated with the change in PINP (r = -0.612, P = 0.001) and the ratio of AIMB to AFVB (r = -0.806, P < 0.001) from baseline to month 12.

CONCLUSIONS

In postmenopausal single-level KD patients, conservative treatment with teriparatide was better than alendronate at preventing the progressive vertebral collapse.

Percutaneous vertebroplasty versus kyphoplasty for the treatment of neurologically intact osteoporotic Kümmell's disease

BACKGROUND

Percutaneous vertebroplasty (PVP) and kyphoplasty (PKP) have been widely used to treat neurologically intact osteoporotic Kümmell's disease (KD), but it is still unclear which treatment is more advantageous. Our study aimed to compare and investigate the safety and clinical efficacy of PVP and PKP in the treatment of KD.

METHODS

The relevant data that 64 patients of neurologically intact osteoporotic KD receiving PVP (30 patients) or PKP (34 patients) were analyzed. Surgical time, operation costs, intraoperative blood loss, volume of bone cement injection, and fluoroscopy times were compared. Occurrence of cement leakage, transient fever and re-fracture were recorded. Universal indicators of visual analogue scale (VAS) and Oswestry disability index (ODI) were evaluated separately before surgery and at 1 day, 6 months, 1 year, 2 years and the final follow-up after operation. The height of anterior edge of the affected vertebra and the Cobb's angle were assessed by imaging.

RESULTS

All patients were followed up for at least 24 months. The volume of bone cement injection, intraoperative blood loss, occurrence of bone cement leakage, transient fever and re-fracture between two groups showed no significant difference. The surgical time, the operation cost and fluoroscopy times of the PKP group was significantly higher than that of the PVP group. The post-operative VAS, ODI scores, the height of the anterior edge of the injured vertebrae and kyphosis deformity were significantly improved in both groups compared with the pre-operation. The improvement of vertebral height and kyphosis deformity in PKP group was significantly better than that in the PVP group at every same time point during the follow-up periods, but the VAS and ODI scores between the two groups showed no significant difference.

CONCLUSION

PVP and PKP can both significantly alleviate the pain of patients with KD and obtain good clinical efficacy and safety. By contrast, PKP can achieve better imaging height and kyphosis correction, while PVP has the advantages of shorter operation time, less radiation volume and operation cost.

Modified poly(methyl methacrylate) bone cement in the treatment of Kümmell disease

Kümmell disease (KD) causes serious vertebral body collapse in patients. However, only a few case reports have been conducted and the number of patients with KD investigated was limited. Additionally, the frequently used poly(methyl methacrylate) (PMMA) bone cement for KD is limited by excessive modulus and poor biocompatibility. Herein, we aimed to modify PMMA bone cement with mineralized collagen (MC), and compare the clinical effects, image performance and finite element analysis between the modified bone cement and PMMA bone cement for the treatment of phase I and II KD. Thirty-nine KD patients treated with PMMA bone cement and 40 KD patients treated with MC-modified PMMA bone cement from June 2015 to March 2017 were retrospectively analyzed. The surgical procedure, intraoperative blood loss, hospital stay and complications were compared between different groups. Visual analog scale, Oswestry disability index, anterior vertebral height, posterior vertebral height, computed tomography value, adjacent vertebral re-fracture, Cobb angle and wedge-shaped correction angle were evaluated. Additionally, the representative sample was selected for finite element analysis. We found that the MC-modified PMMA bone cement could achieve the same effect as that of PMMA bone cement and was associated with better vertebral height restoration in the long term.

The role of radiography in the study of spinal disorders

Despite the growing use of computed tomography (CT) and magnetic resonance imaging (MRI) in the study of spinal disorders, radiography still plays an important role in many conditions affecting the spine. However, the study and interpretation of spine radiograph is receiving less attention and radiologists are increasingly unfamiliar with the typical findings in normal and pathologic conditions of the spine. The aim of this article is to review the radiologic indications of radiograph in different pathologic conditions that affect the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumour disorders, as well as their main radiographic manifestations.

Analysis of two minimally invasive procedures for osteoporotic vertebral compression fractures with intravertebral cleft: a systematic review and meta-analysis

Background

A systematic review and meta-analysis to assess the pros and cons of percutaneous vertebroplasty (PVP) versus kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs) with intravertebral cleft (IVC) including all available evidence from controlled trials.

Methods

Databases including Pubmed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched to identify relevant studies comparing PVP and PKP for OVCFs with IVC. The outcomes mainly included visual analog scale (VAS), Oswestry Disability Index (ODI), local kyphotic angle (LKA), rate of vertebral height (VH%), and adverse events.

Results

Nine studies enrolling 688 patients were eligible for meta-analysis. The results indicated no significant differences between the two groups in the short-and long-term VAS, ODI, LKA, or VH% (P > 0.05). Compared with PVP, PKP was associated with significantly longer operation time (P < 0.05), higher cost (P > 0.05), and more injected cement volume (P < 0.05). In terms of adverse events, PKP has a lower risk of cement leakage (P < 0.05), while with no significant difference in adjacent-level fracture rates (P > 0.05).

Conclusion

The two procedures have similar short- and long-term pain relief, functional recovery, local kyphosis correction, and vertebral height maintenance in OVCFs with IVC. PKP is superior to PVP for the injected cement volume, and lower cement leakage rate, however, with longer operation time, more fluoroscopy times, and higher cost. Further randomized controlled trials (RCTs) should be conducted to confirm these results.

Biomechanical finite element analysis of superior endplate collapse after thoracolumbar fracture surgery

Background

In the follow-up after internal fixation of thoracolumbar fractures, the imaging of some patients shows "crater-like" collapse of the superior endplate of the injured vertebra, with variable collapse area and depth, even involving the anterior edge of the vertebral body. Though many papers had described the phenomenon, but nearly no one did biomechanical research about this. So we did this research in a creative way by using finite element model.

Methods

A healthy male volunteer was selected. The 64-slice thin-section spiral computed tomography images at the level of T11-L3 were collected. Data were imported into Mimics 15.0 medical image processing software to establish three-dimensional finite element skeletal models of T11 to L3 containing only three-dimensional surface elements without entities. The model was assigned values and verified. Then the pedicle screw-rod system was added to this model, and five models containing the screw-rod system with different defect sizes as well as five models that simulated the removal of the screw-rod system were derived at the same time (the defect volume was 1/5, 2/5, 3/5, 4/5, or 5/5 of the anterior vertebral column, respectively). Biomechanical analysis was then performed on this basis.

Results

After the removal of the internal fixator, as defect volume increased, the stress difference between the 4/5 defect group and the 5/5 defect group had the greatest magnitude of combined stress under the seven working conditions. When the volume of the collapse defect reached 4/5 of the anterior column of the vertebral body, the concentration of stress increased significantly, suggesting that the risk of continued compression or even refracture of the injured vertebra increased if the internal fixator was removed at that time.

Conclusions

When the volume of the defect in the superior endplate of the injured vertebra reaches 4/5 of the anterior column, the removal of the internal fixator should be carefully considered to avoid refracture of the anterior column of the injured vertebra.

Percutaneous vertebroplasty versus percutaneous kyphoplasty for the treatment of delayed post-traumatic vertebral body collapse (Kümmell’s disease) in Chinese patients: a systematic review and meta-analysis

Objective

To compare the clinical efficacy between percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) in the treatment of Kümmell’s disease in Chinese patients.

Methods

The studies using randomized controlled trials to compare clinical efficacy between PVP and PKP in the treatment of Kümmell’s disease in Chinese patients were retrieved from Embase, Pubmed, Central, Cinahl, PQDT, CNKI, CQVIP, Wanfang Data, and CBM (from September 2008 to September 2018). Keywords for both Chinese and English search were: percutaneous vertebroplasty, PVP, percutaneous kyphoplasty, PKP, and Kümmell’s disease. A total of 132 articles were retrieved based on the search strategy through online database searching and manual searching. Finally, one foreign report and seven Chinese reports were included. After extracting the data, statistical software Review Manager 5.3 was used for data analysis.

Results

Through comparison, Cobb angle (95% CI [0.54, 4.42), P = 0.01] and Oswestry Dysfunction Index (ODI) (95% CI [0.21, 2.15], P= 0.02) of PKP group was smaller than that of PVP group. Postoperative anterior vertebral body height of the PKP group was better than PVP group (95% CI [−1.27, −0.66], P < 0.001]. However, the PVP group had shorter operation time than PKP group (95% CI [−13.48, −7.43), P = 0.001]. In the other outcome measures, including Visual Analogue Scale (VAS) score (95% CI [−0.04, 0.27), P = 0.15), cement volume (95% CI [−0.82, 0.32], P = 0.39) and cement leakage (95% CI [0.90, 2.76], P = 0.11), there was no significant differences between the two procedures.

Conclusions

At this stage, there is sufficient evidence to support that PKP is better than PVP in the treatment of Kümmell’s disease in Chinese patients. Although PVP surgery requires much less operation time, PKP has better postoperative radiological results and lower ODI. Moreover, both of them had similar clinical results (e.g., analgesic effects, cement dosage, and leakage rate). Further evidence is dependent on the emergence of randomized controlled trials with higher quality and larger sample sizes in the future.

Therapeutic efficacy of Transpedicular Intracorporeal cement augmentation with short segmental posterior instrumentation in treating osteonecrosis of the vertebral body: a retrospective case series with a minimum 5-year follow-up

Background

Transpedicular intracorporeal cement augmentation (TCA) with short segmental posterior instrumentation (SSPI), which provides an ideal immediate analgesic effect and long-term reconstructive stability, is thought to be a sensible advancement to the operative strategy in treating osteonecrosis of the vertebral body (ONV). However, long-term follow-up studies about the treatment are scarce.

Methods

Forty-six ONV patients (22 males and 24 females, mean age of 62.8 ± 7.11 years) underwent TCA with SSPI were retrospectively analyzed. During follow-up, clinical outcomes, such as the Visual Analogue Scale (VAS) score and the Oswestry Disability Index (ODI) score, were evaluated, as well as radiologic outcomes, such as the average vertebral height and kyphotic angle.

Results

A total of 36 patients completed a follow-up period of at least 5 years (mean follow-up period of 67 ± 4.2 months). Among them, seven patients experienced complications, i.e., pneumonia (2/36, 5.56%), screw loosening (2/36, 5.56%), moderate hematoma in the subcutaneous tissue (1/36, 2.78%), and cement leakage (2/36, 5.56%). Compared to the preoperative score, the mean VAS score was significantly reduced 6 months postoperatively (P < 0.05), and it concluded being virtually identical to the preoperative score (P > 0.05). The mean ODI score exhibited a comparable trend. Regarding the radiologic evaluation, the mean kyphotic angle and average vertebral body height were significantly corrected postoperatively (both P < 0.05). However, these radiological parameters were maximally ameliorated during the direct postoperative period and slowly deteriorated over time.

Conclusion

The present study shows that TCA with SSPI may be only mildly effective for symptom relief and correction of kyphotic deformity during a relatively long follow-up, thus we do not recommend it for ONV.

Percutaneous kyphoplasty treatment evaluation for patients with Kümmell disease based on a two-year follow-up

Percutaneous kyphoplasty (PKP) has been used in Kümmell disease treatment for years. The objective of the current study was to evaluate the efficacy and safety of PKP in the treatment of patients with Kümmell disease and to explore the association between cement injection volume and pain relief. A total of 50 patients were enrolled in the present study and follow-up was 2 years. Efficacy was evaluated using the Visual Analog Scale (VAS), the Oswestry Disability Index (ODI) and the kyphotic angle (Cobb's angle). VAS and ODI were determined at the initial evaluation (prior to surgery), at 3 days, 3 months, and 1 and 2 years post surgery. Cobb's angle was measured prior to and 3 months, 1 year and 2 years following surgery. PKP safety was assessed by evaluating complications, including cement leakage and spinal cord compression. In the follow-ups, VAS significantly decreased from 7.00±0.78 pre-PKP to 3.14±0.67 at 2 years post-PKP (P<0.05). ODI significantly decreased from 73.88±8.60 prior to surgery to 22.84±8.85 at 1 year following surgery (P<0.05) and did not significantly change at the following 2-year measurement (26.44±8.63). The Cobb's angle, measured at 17.73±2.43° preoperatively, significantly decreased to 8.32±2.21° at 3 months following surgery (P<0.05). On subsequent follow-ups at 1 and 2 years, the Cobb's angle increased to 9.55±2.82 and 10.27±3.22°, respectively. A total of 8 patients exhibited signs of cement leakage during the PKP procedure. No patients experienced severe neurological deficits or complications. Spearman analysis demonstrated a positive correlation between cement injection volume and pain relief. The current study indicated that PKP was a safe and effective treatment for patients with Kümmell disease and that there was a positive correlation between cement injection volume and pain relief. The current study may be used a reference in cement dosing for the treatment of PKP.

Posttraumatic Delayed Vertebral Collapse : Kummell's Disease

Posttraumatic delayed vertebral collapse, known as Kummell’s disease, is increasing in number of patients. This disease is already progressive kyphosis due to vertebral collapse at the time of diagnosis and it causes intractable pain or neurologic deficit due to intravertebral instability. Treatment is very difficult after progression of the disease, and the range of treatment, in hospital day, and cost of treatment are both increased. Clinical features, pathogenesis and radiologic findings of these disease groups were reviewed to determine risk factors for delayed vertebral collapse. The purpose of this article is to suggest appropriate treatment before vertebral collapse for patients with osteoporotic vertebral compression fracture who have risk factors for posttraumatic delayed vertebral collapse.

Posterior Vertebral Column Resection Through Unilateral Osteotomy Approach for Old Lumbar Fracture Combined with Kummell Disease

BACKGROUND

Kummell disease is a clinical syndrome characterized by minor spinal trauma with a symptom-free period from months to years, followed by progressive painful kyphosis. Many surgical options for Kummell disease have been reported in the previous literature; however, no study has mentioned the surgical strategy for patients whose fractured vertebrae were severely compressed and only a slice of superior and inferior end plate was left.

CASE DESCRIPTION

Here we report the case of a 69-year-old woman who suffered persistent severe back pain since she slipped and fell 1 year before medical consult. The patient presented with constrained body posture and pressure pain on the thoracolumbar region. Visual analog scale pain under weight bearing was 90/100, and her Oswestry Disability Index score was 74%. Kummell disease was diagnosed on the basis of clinical presentation, trauma history, radiograph, computed tomography, and magnetic resonance imaging. We performed the posterior vertebral column resection through the unilateral osteotomy approach for the patient, and the clinical outcome and radiologic restoration were recorded. One year after the surgery, outpatient follow-up review revealed that the visual analog scale reduced to 10/100 and Oswestry Disability Index reduced to 13%. The posteroanterior and lateral radiograph in the standing position showed bony fusion was achieved at the osteotomy site. No pseudarthrosis or instrumentation-related failure occurred.

CONCLUSION

Posterior vertebral column resection through unilateral osteotomy approach is an effective method for patients with Kummell disease, especially when the fractured vertebrae compressed severely and only a slice of superior and inferior end plate was left.

Treating osteoporotic vertebral compression fractures with intraosseous vacuum phenomena using high-viscosity bone cement via bilateral percutaneous vertebroplasty

Osteoporotic vertebral compression fractures with intraosseous vacuum phenomena could cause persistent back pains in patients, even after receiving conservative treatment. The aim of this study was to evaluate the efficacy of using high-viscosity bone cement via bilateral percutaneous vertebroplasty in treating patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena.Twenty osteoporotic vertebral compression fracture patients with intraosseous vacuum phenomena, who received at least 2 months of conservative treatment, were further treated by injecting high-viscosity bone cement via bilateral percutaneous vertebroplasty due to failure of conservative treatment. Treatment efficacy was evaluated by determining the anterior vertebral compression rates, visual analog scale (VAS) scores, and Oswestry disability index (ODI) scores at 1 day before the operation, on the first day of postoperation, at 1-month postoperation, and at 1-year postoperation.Three of 20 patients had asymptomatic bone cement leakage when treated via percutaneous vertebroplasty; however, no serious complications related to these treatments were observed during the 1-year follow-up period. A statistically significant improvement on the anterior vertebral compression rates, VAS scores, and ODI scores were achieved after percutaneous vertebroplasty. However, differences in the anterior vertebral compression rate, VAS score, and ODI score in the different time points during the 1-year follow-up period was not statistically significant (P > 0.05).Within the limitations of this study, the injection of high-viscosity bone cement via bilateral percutaneous vertebroplasty for patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena significantly relieved their back pains and improved their daily life activities shortly after the operation, thereby improving their life quality. In this study, the use of high-viscosity bone cement reduced the leakage rate and contributed to their successful treatment, as observed in patients during the 1-year follow-up period.

T1 finite element model of Kümmell's disease shows changes in the vertebral stress distribution

The aims of this study were to develop a finite element model of delayed post-traumatic vertebral osteonecrosis, analyze its effect on the vertebral stress distribution, and provide experimental evidence for osteonecrosis as a risk factor for loss of the vertebral corrective angle. Three-dimensional reconstruction was performed on CT data of the lumbar vertebrae from a 29-year-old male without spinal lesions to develop a normal L1-L3 vertebral model and a model with post-traumatic vertebral osteonecrosis at level L2. Vertebral flexion, extension, and lateral bending were simulated using computer software to determine the stress distribution in the cortical and cancellous bone in the two models and the changes in the vertebral stress distribution with the size and location of the cavity. Simulation of a vertebral cavity tended to increase the Von Mises equivalent stress in the vertebral cancellous bone and reduce the equivalent stress in the cortical bone, while the vertebral equivalent stress displayed a reverse distribution. The equivalent stress was increased in both the cancellous and cortical bones with increasing cavity volume, and the equivalent stress in the cortical bone was always smaller than that in the normal vertebrae. Placing the cavity close to the endplate of the vertebrae tended to cause stress concentrations in the cancellous bone around the endplate. The cancellous bone with post-traumatic osteonecrosis tended to experience greater Von Mises equivalent stress than the normal vertebrae. Differences in the cavity volume and location may result in a more severe abnormal stress distribution.