The association of sacroiliac joint bridging with other enthesopathies in the human body

Mobility and anthropometry of the sacroiliac joint: range of motion and morphological characteristics

Purpose

The sacroiliac joint (SIJ), a synovial joint with irregular surfaces, is crucial for stabilizing the body and facilitating daily activities. However, recent studies have reported that 15-30% of lower back pain can be attributed to instability in the SIJ, a condition collectively referred to as sacroiliac joint dysfunction (SIJD). The aim of this study is to investigate how the morphological characteristics of the auricular surface may influence the SIJ range of motion (ROM) and to examine differences in SIJ ROM between females and males, thereby contributing to the enhancement of SIJD diagnosis and treatment.

Methods

We measured SIJ ROM using motion-analysis cameras in 24 fresh cadavers of Korean adults (13 males and 11 females). Using three-dimensional renderings of the measured auricular surface, we investigated the correlations between the morphological characteristics of the auricular surface and the ROM of the SIJ.

Results

The SIJ ROM was between 0.2° and 6.7° and was significantly greater in females (3.58° ± 1.49) compared with males (1.38° ± 1.00). Dividing the participants into high-motion (3.87° ± 1.19) and low-motion (1.13° ± 0.62) groups based on the mean ROM (2.39°) showed no significant differences in any measurements. Additionally, bone defects around the SIJ were identified using computed tomography of the high-motion group. In the low-motion group, calcification between auricular surfaces and bone bridges was observed.

Conclusion

This suggests that the SIJ ROM is influenced more by the anatomical structures around the SIJ than by the morphological characteristics of the auricular surface.

Lumbosacral zone features in individuals with nonspecific chronic low back pain are unique compared to controls and correlate with pain and dysfunction

OBJECTIVES

To compare the lumbosacral nerve distances (LNDs) and sacroiliac joint (SIJ) morphology in individuals with nonspecific chronic low back pain (NSCLBP) and control and examine their correlations with pain and dysfunction in the former.

MATERIALS AND METHODS

The sample includes 200 adult patients (ranging from 20 to 50 years old) referred for computerized abdominal tomography (CT): 100 individuals with NSCLBP (50 males and 50 females) and 100 individuals without NSCLBP (50 males and 50 females). CT scans were assessed for LNDs, degenerative sacroiliac changes, and joint bridging. Those factors were correlated to the outcomes of three self-reported questionnaires about pain and function (Oswestry, Fear-Avoidance, and Numerical Pain Rating Scale) in the NSCLBP group.

RESULTS

Individuals with NSCLBP tend to have reduced LNDs from the sacral part of the SIJ compared to controls (males: right Δ = 5.8 mm, left Δ = 6.03 mm; females: right Δ = 7.9 mm, left Δ = 7.73 mm, two-way ANOVA, p < 0.01), with moderate significant negative correlations with all three questionnaires (-0.38 < Pearson's r < - 0.57, p < 0.02, i.e., reduced LNDs with greater disability and pain). The NSCLBP group had more significant SIJ degeneration severity that moderately correlated with two questionnaires (0.39 < Pearson's r < 0.66, p < 0.04, i.e., greater SIJ degeneration with greater disability and pain). In males, the existence of SIJ bridging strongly correlated with all three questionnaires (0.38 < Pearson's r < 0.78, p < 0.03), and in females, only the Fear-Avoidance Questionnaire and Numerical Pain Scale (0.29 < Pearson's r < 0.41, p < 0.04).

CONCLUSION

Compared to controls, individuals with NSCLBP have reduced LNDs and worse SIJ degenerative changes that correlate with function and pain.

KEY POINTS

• Individuals with nonspecific low back pain tend to have reduced lumbosacral nerve distances than healthy controls. This may be due to entrapments or inflammation of the nerves or surrounding tissues. • Individuals with nonspecific low back pain tend to have more severe degeneration of their sacroiliac joint than healthy controls. • The above findings significantly correlated with the scores of three self-reported questionnaires about pain and function, implicating that they may be of clinical significance.

Sacroiliac Joint Variation in Patients With Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

Ossification of the posterior longitudinal ligament (OPLL) reveals heterotopic ossification in the spinal ligament. OPLL also tends to ossify ligaments and entheses throughout the body. However, hallmarks of sacroiliac (SI) joint ossification and its variation in OPLL have not been clarified. Here, we investigated the morphological changes in SI joints in individuals with and without OPLL.

METHODS

We included 240 age- and sex-matched patients (OPLL+, 120; OPLL-, 120) in the study. SI joint variations were classified into 4 types: Type 1, normal or small peripheral bone irregularity; Type 2, subchondral bone sclerosis and osteophyte formation; Type 3, vacuum phenomenon; and Type 4, bridging osteophyte and bony fusion. Type 4 was further divided into 3 subgroups as previously described. Interactions between the ossified spinal region in OPLL and morphological changes in the SI joint were evaluated.

RESULTS

SI joint ankylosis occurs more frequently in patients with OPLL (51.7%) than in those without (non-OPLL) (33.3%). The SI joint vacuum phenomenon (49.2%) was the main finding in non-OPLL. SI joint ankylosis in OPLL was characterized by anterior bridging and intra-articular fusion. OPLL patients with multilevel ossification tend to develop degeneration and ankylosis of the SI joints.

CONCLUSIONS

OPLL conferred a high risk of SI joint ossification compared with non-OPLL, and patients with extensive ossification had a higher rate of SI joint ankylosis. Understanding SI joint variation could help elucidate OPLL etiology and clarify the phenotypic differences in the SI joint between OPLL and other spinal disorders.

Back-to-back: The co-occurrence of DISH and ankylosing spondylitis from early modern Poland

OBJECTIVE

This case study evaluates an individual with skeletal changes consistent with DISH and ankylosing spondylitis. We present here an evaluation of the individual's pathological skeletal changes and a review of the potential diagnoses. Finally, we offer a differential diagnosis of co-morbidity infrequently found in the paleopathological record.

MATERIALS

The skeletal remains of a male, aged 50 + years from the early modern Polish (17th-18th century CE) site of Drawsko 1.

METHODS

Skeletal remains were examined for the presence of spondyloarthropathies.

RESULTS

The individual presented with anterolateral fusion of the vertebral bodies of T6-T10 with a "dripping candle wax" appearance, fusion of the right costovertebral joint at rib 8, fusion of the left apophyseal joints of T8-T10, and the calcification of the supraspinous ligament at T3-T4. The left sacroiliac joint shows intra-articular and para-articular fusion; the right has bony changes consistent with ongoing fusion. Entheseal reactions were noted on the left clavicle, scapulae, first metacarpals, ulnae, and humerii. Diffuse idiopathic skeletal hyperostosis (DISH), ankylosing spondylitis (AS), reactive arthritis (RA), psoriatic arthritis (PA), and enteropathic arthritis (EA) are considered as differential diagnoses.

CONCLUSIONS

Based on the skeletal pattern of involvement, the individual suffered from both DISH and AS, which has previously been reported once in the paleopathological literature since 1950. The clinical literature indicates that co-occurrence of these two conditions is possible, with approximately 40 individuals affected.

SIGNIFICANCE

This case study is significant for demonstrating the co-occurrence of DISH and AS in the paleopathological record. Additionally, this case contributes to the understanding of heterogenous frailty and syndemics.

LIMITATIONS

No radiographs were taken to confirm the differential diagnosis. No aDNA analysis was conducted.

SUGGESTIONS FOR FURTHER RESEARCH

The remains have been reburied; no further analysis is possible.

Imaging Characteristics of Diffuse Idiopathic Skeletal Hyperostosis: More Than Just Spinal Bony Bridges

Diffuse idiopathic skeletal hyperostosis (DISH) is a systemic condition characterized by new bone formation and enthesopathies of the axial and peripheral skeleton. The pathogenesis of DISH is not well understood, and it is currently considered a non-inflammatory condition with an underlying metabolic derangement. Currently, DISH diagnosis relies on the Resnick and Niwayama criteria, which encompass end-stage disease with an already ankylotic spine. Imaging characterization of the axial and peripheral skeleton in DISH subjects may potentially help identify earlier diagnostic criteria and provide further data for deciphering the general pathogenesis of DISH and new bone formation. In the current review, we aim to summarize and characterize axial and peripheral imaging findings of the skeleton related to DISH, along with their clinical and pathogenetic relevance.

Association of Inflammation, Ectopic Bone Formation, and Sacroiliac Joint Variation in Ossification of the Posterior Longitudinal Ligament

Ossification of the posterior longitudinal ligament (OPLL) is considered a multifactorial condition characterized by ectopic new bone formation in the spinal ligament. Recently, its connections with inflammation as well as sacroiliac (SI) joint ankylosis have been discussed. Nevertheless, whether inflammation, spinal ligament ossification, and SI joint changes are linked in OPLL has never been investigated. In this study, whole-spinal computed tomography and serum high-sensitive C-reactive protein (hs-CRP) levels were obtained in 162 patients with cervical OPLL. Ossification lesions were categorized as plateau and hill shapes. Accordingly, patients were divided into plateau-shaped (51 males and 33 females; mean age: 67.7 years) and hill-shaped (50 males and 28 females; mean age: 67.2 years) groups. SI joint changes were classified into four types and three subtypes, as previously described. Interactions among ossification shapes, hs-CRP levels, and morphological changes in the SI joint were investigated. The plateau shape was more common in the vertebral segments (59.5%), compared to the hill shape, which was predominant in the intervertebral regions (65.4%). Serum hs-CRP levels in the plateau-shaped group (0.11 ± 0.10 mg/dL) were significantly higher than those in the hill-shaped group (0.07 ± 0.08 mg/dL). SI joint intra-articular fusion was the main finding in the plateau-shaped group and showed significantly higher hs-CRP levels compared to the anterior para-articular bridging, which more frequently occurred in the hill-shaped group. Our findings suggested a possible inflammation mechanism that might contribute to the new bone formation in OPLL, particularly the plateau shape.

Morphometric Examination of the Sacroiliac Region and Variable Positions of the Sacral Auricular Surface: Anatomical Classification and Importance

OBJECTIVES

Anatomical variations of the sacrum involve alterations in the number of sacral segments, auricular surface area, and neural arch dimensions and are associated with biomechanical, surgical, and obstetric implications. Due to the complex functional structure of the sacroiliac (SI) joints, it was aimed to evaluate their morphometric structure, classify the sacrum, and group different locations of the auricular surface in the sacrums.

METHODS

Sex determination was made in 91 dry human sacra. Determination of the alpha angle on the sagittal axis of the auricular surface of the sacrum and classification of the auricular surface of the sacrum was performed. The sacra were studied to determine the position and extent of their auricular surfaces in relation to the sacral segments. Specimens were grouped as "normal," "high-up," and "low-down" auricular surface-bearing sacra. The sacral surface areas were measured, and SI joints were classified into three types morphologically (types I, II, and III). The depth and anterior-posterior length of the cranial, middle, and caudal impressions observed in the posterior sacrum and anterior-posterior lengths were measured.

RESULTS

The measurements made for sex determination showed that 46 of the sacra were from females and 45 were from males. The alpha angle on the sagittal axis of the sacral auricular surface was found to be greatest at the level of the first posterior sacral foramina. While the most common sacrum type was Type III, the least common type was Type I. The surface area of facies auricularis was found to be larger in males than in females. With regard to facies auricularis in all sacrum groups, although it covered approximately 2.5 sacral vertebrae, there was a difference in the location of facies auricularis in the sacral vertebrae. A statistically significant difference was found between right and left in the depth values of the impressions in the dorsal surface of the sacrum (p <0.05).

CONCLUSION

The position of the auricular surface in the sacrum differed among individuals. These differences are associated with variable load-bearing in the SI joints. The biomechanical classification of the sacrum and localization of the auricular surface can provide information about the anatomic source of low back pain or help predict the location of low back pain. Changes in the synovial surface morphology of the SI joints may elicit sacroiliac joint pain. This study was conducted because it is considered that the location of the auricular surface can significantly affect load-bearing patterns of the sacrum.

Skeletal evidence of Diffuse Idiopathic Skeletal Hyperostosis (DISH) in a collective burial from Byzantine Greece

The paper reports on a collective burial from a 13th c. AD cist grave in Attica, Greece. The grave was located inside a basilica and held the remains of at least ten adults. Bone representation analysis showed secondary manipulation of previous deceased including long bone selection for reburial in the same grave and/or bones transported from a different burial place. Paleopathological analysis used macroscopy and radiology, and revealed several lesions on the axial and appendicular skeleton expressed mainly by spinal ligament ossification and multiple peripheral enthesopathies. Individuation of the remains pointed to a middle-aged male with DISH, a condition often correlated to high social rank. Byzantine period is marked by increasing development and prosperity in Greece including among others the creation of many local monastic centers. Although the precise social and professional profile of these individuals cannot be revealed, the combined investigation of skeletal and archaeological evidence suggests that the grave gathered the remains of individuals belonging to an upper class social group.

Utility of Plain Radiographs in Metabolic Bone Disease - A Case-Based Pictorial Review from a Tertiary Centre

In this era of advanced high-tech imaging, the utility of plain radiographs in conditions of the bone is increasingly being overseen by both clinicians and radiologists. Plain radiography is the first-line, essential screening or diagnostic tool for diverse bone diseases, where magnetic resonance imaging (MRI) may be non-contributory. Plain radiographs often play a pivotal role in diagnosing metabolic bone disorders. This paper from a single tertiary care centre discusses ten real-life patients with metabolic bone conditions and other bone diseases with near-normal MRI of the spine, in whom plain radiographs revealed subtle findings and aided in making diagnoses.

Each of these cases had a non-specific clinical presentation. They all showed inconclusive features on MRI, but subtle important radiographic findings led to a specific diagnosis.

Plain radiography is key in diagnosing bone diseases. Many of these metabolic conditions clinically mimic rheumatologic conditions owing to non-specific arthralgia and back pain. Familiarity with subtle radiographic findings of these conditions may lead to early diagnosis and treatment, resulting in improved patient outcomes.

Characterization of individuals with sacroiliac joint bridging in a skeletal population: analysis of degenerative changes in spinal vertebrae

The aim of this study was to characterize the individuals with sacroiliac joint bridging (SIB) by analyzing the degenerative changes in their whole vertebral column and comparing them with the controls. A total of 291 modern Japanese male skeletons, with an average age at death of 60.8 years, were examined macroscopically. They were divided into two groups: individuals with SIB and those without bridging (Non-SIB). The degenerative changes in their whole vertebral column were evaluated, and marginal osteophyte scores (MOS) of the vertebral bodies and degenerative joint scores in zygapophyseal joints were calculated. SIB was recognized in 30 individuals from a total of 291 males (10.3%). The average of age at death in SIB group was significantly higher than that in Non-SIB group. The values of MOS in the thoracic spines, particularly in the anterior part of the vertebral bodies, were consecutively higher in SIB group than in Non-SIB group. Incidence of fused vertebral bodies intervertebral levels was obviously higher in SIB group than in Non-SIB group. SIB and marginal osteophyte formation in vertebral bodies could coexist in a skeletal population of men. Some systemic factors might act on these degenerative changes simultaneously both in sacroiliac joint and in vertebral column.

Diffuse idiopathic skeletal hyperostosis (Forestier-Rotes-Querol disease): what's new?

Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier-Rotes-Querol disease, is characterized by the ossification of the entheses (i.e., enthesopathy). The diagnosis of DISH requires at least two (according to Forestier) or three (according to Resnick) contiguous intervertebral bridges, without severe disk alterations (in contrast to degenerative spinal disease) or ankylosis of the sacroiliac or facet joints (in contrast to spondylarthritis). Although prevalence estimates vary with the number of bridges used to define the disease, the prevalence of DISH is consistently high and increases with age and obesity. Peripheral involvement is common but difficult to ascribe to DISH in the absence of typical spinal changes. Cervical spine ossification is the most extensively studied manifestation, as dysphagia due to esophageal compression may require surgery. As with spondylarthritis, vertebral fractures on a hyperostotic fused spine may escape recognition, placing the patient at risk for complications in the event of subsequent displacement. These fractures are particularly severe, as they often involve the cervical spine and can therefore, cause major neurological impairments. DISH is associated with an increased risk of metabolic syndrome (odds ratio, 3.88). Research into the pathophysiology of DISH has established that serum levels of the natural osteogenesis inhibitor Dickkopf-1 (DKK-1) are low in patients with DISH or spondylarthritis. Although this abnormality might contribute to the entheseal ossification, it has not been found consistently.

Evidence-based diagnosis and treatment of the painful sacroiliac joint

Sacroiliac joint (SIJ) pain refers to the pain arising from the SIJ joint structures. SIJ dysfunction generally refers to aberrant position or movement of SIJ structures that may or may not result in pain. This paper aims to clarify the difference between these clinical concepts and present current available evidence regarding diagnosis and treatment of SIJ disorders. Tests for SIJ dysfunction generally have poor inter-examiner reliability. A reference standard for SIJ dysfunction is not readily available, so validity of the tests for this disorder is unknown. Tests that stress the SIJ in order to provoke familiar pain have acceptable inter-examiner reliability and have clinically useful validity against an acceptable reference standard. It is unknown if provocation tests can reliably identify extra-articular SIJ sources of pain. Three or more positive pain provocation SIJ tests have sensitivity and specificity of 91% and 78%, respectively. Specificity of three or more positive tests increases to 87% in patients whose symptoms cannot be made to move towards the spinal midline, i.e., centralize. In chronic back pain populations, patients who have three or more positive provocation SIJ tests and whose symptoms cannot be made to centralize have a probability of having SIJ pain of 77%, and in pregnant populations with back pain, a probability of 89%. This combination of test findings could be used in research to evaluate the efficacy of specific treatments for SIJ pain. Treatments most likely to be effective are specific lumbopelvic stabilization training and injections of corticosteroid into the intra-articular space.

[Computed tomography and magnetic resonance imaging for painful spinal column: contributions and controversies]

The use of tomographic imaging techniques, computed tomography (CT) and magnetic resonance imaging (MRI), to complement or replace plain-film radiography in the study of spine pain is becoming more and more common. The aim of this paper is to provide a general review of the CT and MRI manifestations of the wide spectrum of lesions that can cause pain in the spinal column. This spectrum includes degenerative disease, malalignment, tumors, inflammatory processes, and infectious processes. Precise knowledge and accurate reporting of the findings at CT and MRI are fundamental for clinical decision making in patients with spine pain.

A new long-necked 'sauropod-mimic' stegosaur and the evolution of the plated dinosaurs

Stegosaurian dinosaurs have a quadrupedal stance, short forelimbs, short necks, and are generally considered to be low browsers. A new stegosaur, Miragaia longicollum gen. et sp. nov., from the Late Jurassic of Portugal, has a neck comprising at least 17 cervical vertebrae. This is eight additional cervical vertebrae when compared with the ancestral condition seen in basal ornithischians such as Scutellosaurus. Miragaia has a higher cervical count than most of the iconically long-necked sauropod dinosaurs. Long neck length has been achieved by 'cervicalization' of anterior dorsal vertebrae and probable lengthening of centra. All these anatomical features are evolutionarily convergent with those exhibited in the necks of sauropod dinosaurs. Miragaia longicollum is based upon a partial articulated skeleton, and includes the only known cranial remains from any European stegosaur. A well-resolved phylogeny supports a new clade that unites Miragaia and Dacentrurus as the sister group to Stegosaurus; this new topology challenges the common view of Dacentrurus as a basal stegosaur.