Lumbar spine MRI versus non-lumbar imaging modalities in the diagnosis of sacral insufficiency fracture: a retrospective observational study

Insufficiency fractures in patients with sacral chordoma treated with high-dose radiation therapy with and without resection

Objectives

Determine the incidence, location, and features of insufficiency fractures (IFs) in sacral chordoma patients treated with high-dose radiation therapy (HDR) with(out) resection, relative to radiation therapy type and irradiation plans.

Methods

Clinical data, including details of all surgical procedures and radiotherapies of patients histologically diagnosed with sacral chordoma between 2008 and 2023 available at our database, were retrospectively reviewed. Inclusion criteria were as follows: availability of diagnostic, treatment planning and follow-up magnetic resonance and/or computed tomography scans, and completed treatment. Scans were re-evaluated for the presence and location of IF defined as linear abnormalities with(out) bone marrow oedema (BME)-like changes.

Results

From 48 included patients (29 male, median age 66, range 27-85), 22 were diagnosed with 56 IF (45.8%). IF occurred 3-266 months following the treatment. All sacral and iliac bone IF had vertical components parallel to the SI joint. Twenty patients had bilateral and 16 unilateral IF. BME-like changes were visible in 46 IF (82.1%, 0.80, P ≤ .001). In 13/56 IF (23.2%), BME-like changes were seen prior to IF diagnosis; in only 1 patient, BME-like changes did not develop into an IF. Thirty-nine IF (84.7%) occurred within low-dose volume and 7 (15.3%) outside of irradiated volume in 16/44 irradiated patients. Six IF occurred in 1 patient treated with surgery only.

Conclusions

Pelvic IFs are common in sacral chordoma patients treated with definitive or (neo)adjuvant HDR, occurring months to years following treatment. Not all IF occur in the irradiated volume.

Advances in knowledge

When present, BME-like changes indicate risk of IF developing. IF do not heal over time.

Chronic pelvic insufficiency fractures and their treatment

Fragility and insufficiency fractures of the pelvis (FFP) and sacrum (SIF) are increasingly prevalent, particularly among the elderly, due to weakened bone structure and low-energy trauma. Chronic instability from these fractures causes persistent pain, limited mobility, and significant reductions in quality of life. Hospitalization is often required, with substantial risks of loss of independence (64-89%) and high mortality rates (13-27%). While conservative treatment is possible, surgical intervention is preferred for unstable or progressive fractures. FFP and SIF are primarily associated with osteoporosis, with 71% of patients not receiving adequate secondary fracture prevention. Imaging modalities play a crucial role in diagnosis. Conventional radiography often misses sacral fractures, while computed tomography (CT) is the gold standard for evaluating fracture morphology. Magnetic resonance imaging (MRI) offers the highest sensitivity (99%), essential for detecting complex fractures and assessing bone edema. Advanced techniques like dual-energy CT and SPECT/CT provide further diagnostic value. Rommens and Hofmann's classification system categorizes FFP based on anterior and posterior pelvic ring involvement, guiding treatment strategies. Progression from stable fractures (FFP I-II) to highly unstable patterns (FFP IV) is common and influenced by factors like pelvic morphology, bone density, and sarcopenia. Treatment varies based on fracture type and stability. Non-displaced posterior fractures can be managed with sacroplasty or screw fixation, while displaced or unstable patterns often require more invasive methods, such as triangular lumbopelvic fixation or transsacral bar osteosynthesis. Sacroplasty provides significant pain relief but has limited stabilizing capacity, while screw augmentation with polymethylmethacrylate improves fixation in osteoporotic bones. Anterior ring fractures may be treated with retrograde transpubic screws or symphyseal plating, with biomechanical stability and long-term outcomes depending on fixation techniques. FFP and SIF management requires a multidisciplinary approach to ensure stability, pain relief, and functional recovery, emphasizing early diagnosis, tailored surgical strategies, and secondary prevention of osteoporotic fractures.

Applications of SPECT/CT in the Evaluation of Spinal Pathology: A Review

BACKGROUND

Accurate identification of pain generators in the context of low back and spine-related pain is crucial for effective treatment. This review aims to evaluate the potential usefulness of single photon emission computed tomography with computed tomography (SPECT/CT) as an imaging modality in guiding clinical decision-making.

METHODS

A broad scoping literature review was conducted to identify relevant studies evaluating the use of SPECT/CT in patients with spine-related pain. Studies were reviewed for their methodology and results.

RESULTS

SPECT/CT appears to have advantages over traditional modalities, such as magnetic resonance imaging and CT, in certain clinical scenarios. It may offer additional information to clinicians and improve the specificity of diagnosis. However, further studies are needed to fully assess its diagnostic accuracy and clinical utility.

CONCLUSIONS

SPECT/CT is a promising imaging modality in the evaluation of low back pain, particularly in cases where magnetic resonance imaging and CT are inconclusive or equivocal. However, the current level of evidence is limited, and additional research is needed to determine its overall clinical relevance.

CLINICAL RELEVANCE

SPECT/CT may have a significant impact on clinical decision-making, particularly in cases in which traditional imaging modalities fail to provide a clear diagnosis. Its ability to improve specificity could lead to more targeted and effective treatment for patients with spinal pathology.

LEVEL OF EVIDENCE: 4

Assessment of the Initial Diagnostic Accuracy of a Fragility Fracture of the Sacrum: A Study of 56 Patients

STUDY DESIGN

Retrospective study.

PURPOSE

To investigate the clinical manifestations of a fragility fracture of the sacrum (FFS) and the factors that may contribute to a misdiagnosis.

OVERVIEW OF LITERATURE

The number of patients diagnosed with FFS has increased because of extended life expectancy and osteoporosis. Patients with FFS may report nonspecific symptoms, such as back, buttock, groin, and/or leg pain, leading to a misdiagnosis and a delay in definitive diagnosis.

METHODS

Fifty-six patients (13 males and 43 females) with an average age of 80.2±9.2 years admitted to the hospital for FFS between 2006 and 2021 were analyzed retrospectively. The following patient data were collected using medical records: pain regions, a history of trauma, initial diagnoses, and rates of fracture detection using radiography, computed tomography (CT), and magnetic resonance imaging (MRI).

RESULTS

Forty-one patients presented with low back and/or buttock pain, nine presented with groin pain, and 17 presented with thigh or leg pain. There was no history of trauma in 18 patients (32%). At the initial visit, 27 patients (48%) were diagnosed with sacral or pelvic fragility fractures. In contrast, 29 patients (52%) were initially misdiagnosed with lumbar spine disease (23 patients), hip joint diseases (three patients), and buttock bruises (three patients). Fracture detection rates for FFS were 2% using radiography, 71% using CT, and 93% using MRI. FFS was diagnosed definitively using an MRI with a coronal short tau inversion recovery (STIR) sequence.

CONCLUSIONS

Some patients with FFS have leg pain with no history of trauma and are initially misdiagnosed as having lumbar spine disease, hip joint disease, or simple bruises. When these clinical symptoms are reported, we recommend considering FFS as one of the differential diagnoses and performing lumbar or pelvic MRIs, particularly coronal STIR images, to rule out FFS.

FRAGILITY FRACTURES OF THE SACRUM: A SILENT EPIDEMIC

Fragility fractures of the sacrum (FFS) are caused by low-energy trauma in the elderly population. Due to the nuanced symptomatology, many FFS remains unrecognized and the prevalence is underestimated. The clinical presentation varies, typically presenting with weightbearing low back pain without even remembering of a previous trauma. Radiographs are usually insufficient for the diagnosis and second level imaging modalities are required. In particular, magnetic resonance demonstrated the highest diagnostic accuracy. Treatment should aim to guarantee early mobilization and weightbearing, efficient pain relief and early discharge from the hospital to a proper facility for rehabilitation. Conservative treatment is reserved to non-displaced fractures with an adequate pain relief within one week allowing early mobilization. Otherwise, surgical treatment must be preferred. Nowadays, minimally invasive techniques, such as ileo-sacral screws or trans-sacral bar osteosynthesis, are safe and effective procedures and have overcome open procedures. In more complex patterns, with complete dissociation between the pelvic ring and the ilio-lumbar spine, spino-pelvic fixation is the procedure of choice.

Cooccurrence of Fragility Fracture of the Pelvis with Lumbar Degenerative Disease: A Case Report

Introduction

Fragility fractures of the pelvis (FFP) are caused by low-energy impacts and can occur spontaneously in patients with severe osteoporosis. The clinical symptoms of FFP are frequently vague and nonspecific. Moreover, the symptoms of FFP can mimic lumbar spine pathologies. Therefore, accurate diagnosis of FFP is often difficult and the fracture may be misdiagnosed as lumbar degenerative disease. However, little is known regarding what kind of symptoms due to lumbar degenerative disease are similar to the symptoms of FFP.

Case Report

We encountered two cases in which FFP developed during the treatment of lumbar degenerative disease with radiculopathy. Both patients had undergone conservative treatment for lumbar degenerative disease, but their symptoms gradually worsened and they presented with gait disturbance. FFP was diagnosed by imaging, and surgery was required in one case. Both cases showed L3 foraminal stenosis on the image, and the symptoms of L3 radiculopathy presented with thigh pain, hip pain, and knee pain, which is similar to the pain site of FFP. Therefore, diagnosis of FFP was difficult.

Conclusion

In lumbar degenerative diseases presenting with radiculopathy, the pain site may be similar to that of FFP, which may make diagnosis of FFP difficult. Therefore, especially in patients with lumbar degenerative disease presenting with L3 radiculopathy, it is necessary to consider the possibility of FFP and perform MRI imaging to make an early diagnosis when the symptoms change.

Clinical and MRI features of sacral insufficiency fractures after radiotherapy in patients with cervical cancer

Background

To determine the incidence, clinical and MRI features of sacral insufficiency fracture (SIF) after radiotherapy (RT) in patients with cervical cancer.

Methods

Our study included 167 patients with cervical cancer after radiotherapy that underwent pelvic MRI for follow-up. MRIs included pre-enhanced T1-weighted, coronal fat-Suppressed T2-weighted (FS-T2W) and enhanced T1-weighted imaging. The clinical and MRI dates were reviewed. The gold standard of SIF was based on radiologic findings, clinical data and follow-up at least 12 months.

Results

28 patients (10.8%) with 47 sites were diagnosed with SIFs, including 9 patients with unilateral SIF and 19 patients with bilateral SIFs. The median age was 60 years (range 41–72 years), and 89.3% (25/28) of patients were postmenopausal. 64.3% (18/28) of patients were symptomatic, and 53.6% of patients (15/28) had concomitant pelvic fractures. The median interval time from RT to SIFs was 10 months (range 3–34 months). For the lesion-wise analysis based on all MR images, all lesions were detected by visualizing bone marrow edema patterns, and fracture lines were detected in 64.6% (31/47) of SIFs. No soft-tissue tumors were founded. For each MRI sequence analysis, coronal FS-T2WI detected the most bone marrow edema pattern and fracture line than T1WI or enhanced T1WI.

Conclusion

SIF is a common complication in cervical cancer after radiotherapy, which has some certain clinical and MRI features. Coronal FS-T2WI may be more useful to detect and characterize these fractures than other imaging sequences.

Significance of Lumbar MRI in Diagnosis of Sacral Insufficiency Fracture

STUDY DESIGN

Retrospective observational study.

OBJECTIVE

The aim of the present study was to evaluate the role of lumbar magnetic resonance imaging (MRI) in the diagnostic algorithm of sacral insufficiency fractures (SIF). The primary objective was to compare the sensitivity in fracture detection and correct fracture classification according to MRI and computed tomography (CT). The secondary objective was to identify differences of additional pathologies found in MRI of the lumbar spine and the pelvis and their rates.

METHODS

A total of 943 patients (from 2010 to 2017) with fracture of the pelvic ring were screened. All patients without high-energy trauma and radiologic diagnostics consisting of X-ray, CT, and MRI of the pelvis or the lumbar spine including the sacrum were included. Differences in fracture detection and description in the various radiologic procedures were evaluated. Detection rates of additional pathologies in MRI of the pelvis and lumbar spine were recorded.

RESULTS

A total of 77 subjects were included. The sensitivities for SIF were 14% in X-ray and 88% in CT, and all fractures were detected in MRI. MRI showed a more complex fracture pattern compared with CT in 65% of the cases. Additional pathologies were seen in MRI of the lumbar spine (51%) and that of the pelvis (18%).

CONCLUSIONS

We suggest performing MRI of the lumbar spine including the sacrum with coronal STIR (short tau inversion recovery) sequence for elderly patients with suddenly increasing low back pain at an early stage. This procedure might improve fracture detection, classification, and recognition of concomitant pathologies.

A modified MRI protocol for the increased detection of sacrococcygeal fractures in patients with thoracolumbar junction fractures

This study aimed to identify concurrent thoracolumbar junction (TLJ) and sacrococcygeal (SC) fractures using a modified MRI protocol and analyze the risk factors associated with tandem fractures. We retrospectively investigated patients with MRI-confirmed TLJ fractures from January 2017 to March 2020. Patients were divided into two study groups: study 1 with a modified MRI protocol and study 2 with a routine protocol. The modified protocol included an extended field of view of sagittal scans in L-spine MRI covering the full SC spine. In study 1, frequency of concurrent TLJ and SC fractures was investigated. And we analyzed risk factors and compared CT and MRI for detecting SC fractures. In study 2, co-occurrence of both fractures was investigated. A total of 176 and 399 patients with TLJ fractures were enrolled in study 1 and 2, then SC fractures were identified in 53 (30.14%) and 36 patients (9.02%), respectively. An axial loading trauma mechanism was a significant risk factor (Odds ratio 7.0, p < 0.001), and MRI was more sensitive than CT in detecting SC fractures (p < 0.002). Thus, a modified MRI protocol was useful to detect the high occurrence of SC fractures in TLJ fractures, which concurrent fractures increased by an axial loading mechanism.

Pelvic Insufficiency Fractures in Cervical Cancer After Radiation Therapy: A Meta-Analysis and Review

AIM

The aim of the study was to estimate the prevalence of pelvic insufficiency fractures (PIFs) after radiation therapy (RT) in patients with cervical cancer.

PATIENTS AND METHODS

A total of 3,633 patients from 15 cohort studies were included. Proportion meta-analysis was performed to estimate prevalence and subgroup analysis was performed according to imaging modalities for diagnosis of PIF. For continuous variables (age and length of follow-up), meta-regression analysis was performed.

RESULTS

Pooled prevalence estimate of PIF was 14% (95% CI=10-19). Incidence of PIF was higher in studies that used MRI as a diagnostic tool (17%, 95% CI=12-22) than non-MRI (8%, 95% CI=2-14). In meta-regression, we found a significant association of prevalence of PIF with age (p=0.021) but not with length of follow-up (p=0.118).

CONCLUSION

PIF after RT in patients with cervical cancer is not rare. Physicians need to pay attention to PIFs, especially in patients with high-risk factors for osteoporotic fracture.

Sacral Insufficiency Fractures: a Review of Risk Factors, Clinical Presentation, and Management

PURPOSE OF THE REVIEW

Sacral insufficiency fractures (SIF) are a common and often underdiagnosed source of low back pain. In patients with SIF, there is both a compromised sacroiliac joint and weakened sacrum, resulting in decreased resistance to torsional stress, leading to fracture. While conservative medical management is a safe option, minimally invasive intervention may provide improved short and long-term relief of low back pain in patients presenting with SIF. This comprehensive review is undertaken to provide an update to the current understanding of SIF with description of risk factors, clinical presentation, and management.

RECENT FINDINGS

Sacroplasty is a minimally invasive procedure in which polymethylmethacrylate (PMMA) cement is inserted into bone to improve its structural integrity and alleviate symptoms. Balloon sacroplasty (BSP) has also been successful in alleviating pain with minimal cement leakage in SIF patients. Various other interventional techniques, including navigation-assisted screw fixation have been used to address SIF and have shown improvement in pain with minimal side effects. This review included various modalities of treatments available to manage SIF. This review shows that in comparison with nonsurgical management, sacroplasty has been shown to have greater pain reduction and improved mobility.

The Association of Iliac and Sacral Insufficiency Fractures and Implications for Treatment: The Role of Bone Scans in Three Different Cases

Iliac wing fractures are under-diagnosed fractures often associated with sacral insufficiency fractures in osteoporotic patients. They are rarely seen alone. Insufficiency fractures of the iliac bone can often be missed on computerized tomography (CT) and magnetic resonance imaging (MRI) yet identified on radioisotope bone scans. Symptomatic iliac fractures present with more lateralized pain in the hip and groin compared to patients with only sacral insufficiency fractures. Since the acetabulum is the key weight-bearing articulation between the sacrum and pelvis and the femoral head and leg, worsening of iliac stress fractures can have major effects on weight bearing and should be a consideration in patients with persistent pain in this area. The anatomy of the ilium and relationship to other pelvic insufficiency fractures is reviewed as well as treatment options. Typical cases are presented where the iliac fractures were found on bone scan either in addition to the more common sacral fracture or due to the persistence of symptoms of hip and thigh pain.