Biomechanics of the Sacroiliac Joint: Anatomy, Function, Biomechanics, Sexual Dimorphism, and Causes of Pain

A Prospective Multicenter Randomized Controlled Trial on Safety and Procedural Competency in SI Joint Fusion Performed by Interventional Pain Physicians Trained by a Spine Surgeon

BACKGROUND CONTEXT

Sacroiliac joint (SIJ) fusion was traditionally performed exclusively by spine surgeons using a minimally invasive direct lateral approach. With advancements in technology, SIJ fusion has evolved into percutaneous techniques which have been adopted by interventional pain management (IPM) physicians due to their expertise in interventional techniques. However, this expansion has raised safety concerns among spine surgeons regarding "practice creep" and procedural competency gaps. Furthermore, the lack of uniform outpatient credentialing has created an environment where safety oversight may be inconsistent.

PURPOSE

To evaluate and compare the safety and procedural competency of percutaneous posterior-oblique SIJ fusions performed by trained IPM physicians using titanium screws plus a synthetic bioactive glass flowable biologics under direct spine surgeon supervision versus non-spine surgeon supervision.

STUDY DESIGN/SETTING

A prospective multicenter randomized controlled trial conducted across multiple ambulatory surgery centers between 2020 and 2022.

PATIENT SAMPLE

276 adult patients (mean age 56.7 years; 72.1% female) scheduled for SIJ fusion.

OUTCOME MEASURES

The primary outcome measures were surgical complications, deviations, and revisions. These were assessed through medical records and radiographs for at least 6 months post operative.

METHODS

276 patients were in this study and were randomly assigned to Group 1 or Group 2. 66 patients (Group 1; spine surgeon supervised). 67 patients, clinical specialist supervised, plus 143 assigned to sales representatives/independent distributors supervised (Group 2; non-spine surgeon supervised). All primary procedures were performed by 47 IPM physicians who received structured training on the percutaneous posterior-oblique technique by a board-certified orthopedic spine surgeon. Surgical complications, deviations, and revisions were recorded, with follow-up data collected for at least twelve months.

RESULTS

A total of 9 complications (3.3%), 4 deviations (1.4%), and 5 revision cases (1.8%) were observed. Group 1 experienced no complications, deviations, or revisions. In Group 2, 9 complications (4.3%) and 4 deviations (1.9%) occurred between the second and fifth operative days. 5 cases were revised (2.4%).

CONCLUSIONS

Spine surgeon training equipped IPM physicians to safely performed percutaneous posterior-oblique SIJ fusions with titanium screws plus biologics, achieving low complication and revision rates. These findings highlight the importance of incorporating standardized surgeon-led training and certification programs to bridge the competency gap and ensure safe adoption of interventional spine surgery practices by IPM physicians.

Is Sacroiliac Joint Degeneration Associated With Inferior Outcome post-THA?

INTRODUCTION

Osteoarthritis (OA) of the hip is known to be associated with OA in adjacent areas such as the sacroiliac joint (SIJ). This study aimed to 1) describe the prevalence of SIJ OA in a cohort of patients undergoing total hip arthroplasty (THA), 2) test for an association between the degree of hip OA and SIJ OA, and 3) examine if the degree of SIJ OA is associated with outcomes post-THA.

METHODS

This is a retrospective analysis of prospective databases from two tertiary academic centers. There were 1,154 THA cases from 2018 to 2022. The mean age and body mass index were 67 years and 28.73 kg/m2, respectively. Preoperative radiographs were assessed for hip OA via the Tönnis grade, with 0 being the lowest severity and 3, being the highest. The SIJ OA was graded using the Modified New York Criteria (mNYC), ranging from 0: normal to 4: ankylosis. All patients had pre- and postoperative Oxford Hip Score (OHS) measurements, with follow-up at one year. A subset of 589 patients also had 5-level EuroQol 5-Dimension (EQ-5D-5L) pre- and postoperative as a lifestyle measure. Complications, reoperations, and revisions were recorded. Data was analyzed using Statistical Analysis System (SAS) version 9.4 (SAS Institute Inc., Cary, North Carolina, USA).

RESULTS

There was a high prevalence of advanced SIJ OA, with 39.3% (453) mNYC three cases and 1.4% (16) mNYC four cases. The association between Tönnis grade and mNYC was weak but significant (ρ=0.19, P =0.047). There was no difference in OHS at one year when accounting for age, hip OA, or baseline OHS (P < 0.216).

CONCLUSION

There is a high prevalence of SIJ pathology in patients undergoing THA, but a weak association between SIJ and hip OA. The SIJ pathology and outcomes following THA had no association, indicating that for patients presenting with concurrent hip and SIJ OA, the SIJ should not direct treatment.

The presence of abnormal palpatory findings in the sacrococcygeal area is correlated with chronic pelvic pain: a cross-sectional study

OBJECTIVE

This study examines the prevalence of abnormal palpatory findings (APFs) in the different pelvic areas among individuals with chronic pelvic pain syndrome (CPP-CPPS) and assesses correlations between APFs and clinical and psychosocial symptoms.

METHODS

In this cross-sectional study, 326 participants (162 CPP-CPPS patients, 164 controls) underwent a standardized palpatory assessment of the sacroiliac, sacrococcygeal, and pelvic floor regions. The manual procedure was performed by two expert physiotherapists with a certification in osteopathic manipulation, following a consensus training. We assessed symptom severity and psychosocial variables using the NIH Chronic Prostatitis Symptom Index (NIH-CPSI), the Hospital Anxiety and Depression Scale (HADS), and the Fear Avoidance Belief Questionnaire (FABQ). Correlation analyses explored relationships between APFs, the presence of pain, and psychosocial variables.

RESULTS

APFs were significantly associated with CPP/CPPS, particularly in the sacrococcygeal (r = 0.609, p < 0.01) and pelvic floor (r = 0.620, p < 0.01) regions, indicating a moderate-to-strong correlation. The multivariate analysis confirmed that sacrococcygeal APFs (OR 3.02, 95% CI 1.96-4.65, p < 0.001) and pelvic floor APFs (OR 2.99, 95% CI 1.87-4.78, p < 0.001) were independently associated with CPP/CPPS, whereas sacroiliac findings showed a weak correlation. The correlations between APFs and psychosocial issues (anxiety, depression, fear-avoidance) were weak (r = 0.25).

CONCLUSIONS

Sacrococcygeal and pelvic floor APFs appear to be important clinical markers of CPP/CPPS. Their presence may help identify patients who could benefit from targeted manual therapy as part of multimodal management. Further research should evaluate the prognostic value of these findings.

Spinal Cord Stimulation for Intractable Pain Caused by Sacroiliac Joint Dysfunction: A Case Report

Sacroiliac joint dysfunction is one of the causes of lower back pain, and although it has characteristic pain locations and aggravating factors, it is difficult to diagnose and is often overlooked. A case of relief of typical pain symptoms due to sacroiliac joint dysfunction by spinal cord stimulation is presented. A 60-year-old woman presented with severe chronic pain in the left lumbar, lower buttock, iliac, and groin areas that worsened even when sitting for short periods, as well as numbness in the right lower extremity. The patient had chronic lower back pain since experiencing acute lumbosacral sprains in her 20s and 40s, and her symptoms worsened without any trigger in her 60s. Standard imaging examinations showed no lesions that could be causing the pain, and blood tests showed no inflammation or other abnormalities. Although pharmacological treatment did not provide sufficient analgesia, sacroiliac joint block provided a significant analgesic effect, leading to a definitive diagnosis of sacroiliac joint dysfunction. A spinal cord stimulation trial was performed using percutaneous 8-contact leads placed at the thoracic vertebra 8-11 level, and pain relief was confirmed. One month later, 2 new percutaneous 16-contact leads and an implantable pulse generator were implanted simultaneously. One month after implantation, the visual analog scale and the quick inventory of depression symptomatology scores decreased dramatically from 83 to 8 and from 16 to 4, respectively. In addition, the numbness of the right lower extremity disappeared. These analgesic effects were sustained for 12 months.

Cooled radiofrequency ablation provides extended clinical utility in the management of chronic sacroiliac joint pain: 12-month follow-up results from the observational phase of a randomized, multicenter, comparative-effectiveness crossover study

INTRODUCTION

Sacroiliac joint (SIJ) pain comprises up to 30% of cases of mechanical low back pain (LBP), the leading cause of disability worldwide. Despite sacral lateral branch cooled radiofrequency ablation (CRFA) showing efficacy in clinical trials, there is a lack of comparative-effectiveness long-term follow-up.

METHODS

In this randomized, multicenter, comparative-effectiveness study, 210 patients with injection-confirmed SIJ pain who responded to prognostic lateral branch blocks were randomly assigned to receive CRFA of the L5 dorsal ramus and S1-S3/4 lateral branches or standard medical management (SMM) consisting of pharmacotherapy, physical therapy, injections, and integrative therapies. Patients were followed up at 1, 3, 6, 9, and 12 months, with participants reporting unsatisfactory SMM outcomes being allowed to crossover (XO) and receive CRFA at 3 months. The primary outcome measure was the mean change in average LBP score on a 0-10 Numeric Rating Scale (NRS), with secondary outcomes including measures of quality of life (QoL) and function. A responder was defined as a participant who experienced a ≥30% or ≥2-point decrease in average daily NRS pain score coupled with a score ≥5 out of 7 (moderately better) on the Patient Global Impression of Change scale.

RESULTS

At 12 months, the mean NRS pain score declined from a baseline of 6.4±1.4 to 3.5±2.6, with 57.4% (35/61) of participants in the randomized CRFA cohort experiencing a ≥2-point or 30% decrease in average LBP from baseline. In the crossover cohort, 35/63 (55.6%) subjects had the same experience 12 months following the XO procedure; in the XO group, the mean LBP decreased from 6.1±1.5 to 3.4±2.5. Patients also experienced clinically meaningful improvements in QoL via EuroQoL-5D-5L at 12 months (mean change of +0.22±0.27 in the originally-treated CRFA group and +0.21±0.33 in the XO group). Oswestry Disability Index (ODI) scores also improved by 12.4%±14.7 (CRFA) and 13.7%±17.1 (XO) from baseline at study-end. No serious adverse events related to the CRFA procedure were reported.

CONCLUSION

CRFA in patients with SIJ pain provided clinically significant and sustained improvements for 12 months following a single CRFA treatment, regardless of previous SMM treatment.

TRIAL REGISTRATION NUMBER

NCT03601949.

Fixation of the Sacroiliac Joint: A Cadaver-Based Concurrent-Controlled Biomechanical Comparison of Posterior Interposition and Posterolateral Transosseous Techniques

OBJECTIVE

Our study aimed to compare the posterior interposition technique against the posterolateral transosseous technique in the same cadaver specimens.

METHODS

Computer and cadaver models of 2 fixation techniques were developed. The computer model was constructed to analyze bone volume removed during implant placement and the bony surface area available for fusion. The cadaver model included quasi-static multidirectional bending flexibility and dynamic fatigue loading. Relative motions between the sacrum and ilium were measured intact, after joint destabilization, after fixation with direct-posterior and posterolateral techniques, and after 18,500 cycles of fatigue loading. Relative positions between each implant and the sacrum and ilium were measured after fixation and fatigue loading to ascertain the quality of the bone-implant interface. The 2 techniques were randomized to the left and right sacroiliac joints of the same cadavers.

RESULTS

The posterior interposition technique removed less bone volume and facilitated a larger surface area available for bony fusion. Posterior interposition significantly reduced the nutation/counternutation motion of the sacroiliac joint (42% ± 8%) and reduced it more than the posterolateral transosseous technique (14% ± 4%). Upon fatigue loading, the posterior interposition implant maintained the bone-implant interface across all specimens, while the posterolateral transosseous implant migrated or subsided in 20%-50% of specimens.

CONCLUSION

Posterior interposition fixation of the sacroiliac joint reduces joint motion. The amount of fixation from the posterior technique is superior and more durable than the amount of fixation achieved by the posterolateral technique.

Management of extremity and pelvic fractures in earthquake: our observations and recommendations

BACKGROUND

Earthquakes frequently cause injuries to the musculoskeletal system. Studies conducted after earthquakes often report on injured limbs, fractures, and surgeries. This study aimed to enhance preparedness for future earthquakes by acquiring knowledge about the prevalence of fractures and the relationship between fracture types and injury mechanisms.

METHODS

A retrospective analysis was conducted on medical records of patients with fractures admitted to our hospital following the 2023 Kahramanmaraş Earthquake. Patients with fractures resulting from traffic accidents or other causes unrelated to earthquakes were excluded. The recorded data included age, gender, fracture site, fracture type, mechanism of injury, date, duration of surgery, and peak creatine kinase (CK) level. The injury mechanisms were classified into four main categories: injured by falling objects, falling while running, falling from height, and being trapped under rubble. The study investigated the relationship between fractures and other factors.

RESULTS

The study included 185 patients with a mean age of 39.62 ± 20.83 years. The most frequent mechanism of injury was being trapped under rubble. In total, there were 214 fractures, with pelvic fractures being the most common (21.50% of all fractures). Tibia fractures were the most common fractures in the lower extremities (15.89%). Women had a significantly higher occurrence of pelvic fractures (33.3%) compared to men (14.5%) (p = 0.003). The frequency of pelvic fractures significantly increased as age decreased (p = 0.007). Patients with pelvic fractures had a significantly greater peak CK concentration (p = 0.006). Open fractures were more common in the first few days, and Kirschner wires were the first treatment applied at a mean of 74 h and external fixators at a mean of 94.3 h.

CONCLUSION

Injuries from falling objects from roofs and jumping from heights are important in earthquakes. In addition to lower extremity fractures, pelvic fractures are common in earthquake disasters. Most pelvic fractures are simple lateral compression fractures and it is important to follow the patients for crush syndrome in the first days instead of focusing on definitive fracture treatment. Open fractures should be prioritized for fracture surgery within the first few days. External fixators and Kirschner wires are recommended. Closed fractures should be treated conservatively and definitive surgical procedures should be postponed to the following weeks.

Sacroiliac joint auricular surface morphology modulates its mechanical environment

The sacroiliac joint (SIJ) exhibits significant variation in auricular surface morphology. This variation influences the mechanics of the SIJ, a central node for transmitting mechanical energy from upper body to lower limbs and vice versa. The impact of the auricular surface morphology on stress and deformation in the SIJ remains poorly understood to date. Computed tomography scans obtained from 281 individuals were included to extract the geometry of the pelvic ring. Then, the auricular surface area, SIJ cartilage thickness, and total SIJ cartilage volume were identified. Based on these reconstructions, 281 finite element models were created to simulate SIJ mechanical loading. It was found that SIJ cartilage thickness only weakly depended on age or laterality, while being strongly sex sensitive. Auricular surface area and SIJ cartilage volume depended weakly and non-linearly on age, peaking around menopause in females, but without significant laterality effect. Larger SIJs, characterized by greater auricular area and cartilage volume, exhibited reduced stress and deformation under loading. These findings highlight the significant role of SIJ morphology in its biomechanical response, suggesting a potential link between morphological variations and the risk of SIJ dysfunction. Understanding this relationship could improve diagnosis and targeted treatment strategies for SIJ-related conditions.

Phase-specific changes in hip joint loading during gait following sacroiliac joint fusion: Findings from a finite element analysis

BACKGROUND

Low back pain affects over 80 % of adults, with sacroiliac joint dysfunction accounting for 15-30 % of these cases. Sacroiliac fusion is a surgical procedure for refractory joint pain. While the biomechanics of the joint and its fusion relative to the spinal column are well-known, the hip-spine relationship post-fusion remains unclear. Understanding the biomechanical state following fusion can enhance patient recovery and optimize surgical outcomes. This study uses finite element analysis to assess hip joint biomechanics following sacroiliac joint fusion.

METHODS

CTs of a 55-year-old male were used to create a biomechanical model, validated against a cadaveric study. Three triangular titanium alloy implants were placed across the sacroiliac joint in a unilateral and bilateral configuration. The model, loaded with pelvis and hip joint kinematics during a gait cycle, calculated joint reaction forces, contact stress and area on the hip joint across various gait phases.

FINDINGS

Hip joint contact stresses varied with fixation configurations and gait phases. Unilateral right fusion reduced joint reaction forces by 2 % but increased contact stress by 3.7 %. Bilateral fusion increased joint reaction forces by 6.7 % and contact stress by 3.25 %, with higher stress during foot flat and heel off phases compared to unilateral fixation.

INTERPRETATION

Fusion alters hip loading patterns during specific gait phases, with bilateral fusion producing the highest stresses during foot flat and heel off. These findings may suggest the need for fusion-specific rehabilitation protocols and warrants further investigation of long-term joint health outcomes.

Contraction ratio of multifidus and erector spinae muscles in unilateral sacroiliac joint pain: A cross-sectional trial

Sacroiliac joint (SIJ) pain is one of the most prevalent reasons for disability, it affects the contraction ratio of the muscles of the back. Imaging is critical for diagnosing back muscles. The purpose of this study was to look at changes in the muscle contraction ratio of the lumbar multifidus (LM) and erector spinae (ES) in unilateral SIJ pain. This research included 60 individuals (30 with unilateral SIJ pain and 30 healthy people (who served as matching controls). The contraction ratio of back muscles such as ES and LM was assessed using real-time ultrasonography, and the results were compared between the affected and non-affected sides in patients with unilateral SIJ pain, and healthy participants as well. In the study group, the contraction ratio of ES and LM muscles on the non-affected side was significantly higher than on the affected side (p < 0.05). as well as a significant increase in contraction ratio of the ipsilateral side (affected matched control side) LM of the healthy group compared with that of the non-affected side of the study group (p < 0.001), while there was no significant difference in contraction ratio of the contralateral (unaffected matched control side) ES of the healthy group compared with that of the non-affected side of the study group. The results of this trial demonstrate that patients with unilateral SIJ pain exhibited a substantially lower muscle contraction ratio in the ES and LM of the affected side than the non-affected side in the study group, as well as a significant increase in the contraction ratio of the ES and MF on the ipsilateral side of the control group compared with that of the study group. However, there was no significant change in the contraction ratio of the contralateral ES in healthy individuals compared to the non-affected side of the study group. The findings of the study may help in designing an appropriate exercise program to deal with patients with SIJ pain.

Improvement in Gait Abnormality Following Minimally Invasive Posterior Sacroiliac Joint Fusion

Background Sacroiliac joint (SIJ) dysfunction is a common cause of low back pain and associated gait disturbances that result from aberrant muscle activity and symmetry. This study evaluated the magnitude of improvement in gait characteristics in patients with chronic SIJ pain followed for six months after minimally invasive posterior SIJ fusion. Methods This was a single-arm, prospective, pilot study at two private practice orthopedic pain clinics. Gait characteristics were quantitated using a wireless wearable sensor. Ten patients (mean age: 63 ± 12 years) with abnormal SIJ-associated gait impairment were enrolled and underwent posterior SIJ fusion. Results Average gait velocity improved significantly from 69 ± 28.5 cm/sec at baseline to 99.9 ± 31.5 cm/sec at six months, reflecting an overall average improvement of 30.93 cm/sec or 55.4% (p=0.003). Gait speed, variability, and symmetry impairment parameters also improved with corresponding mean percentage improvements at six months of 27.8% (p=0.02), 19.7% (p=0.17), and 11% (p=0.27). A significant decrease in fall risk and increased timed-up-and-go assessments were noted, with improvements of 32.3% and 24.7%, respectively (p=0.004 for both comparisons). Conclusion These pilot findings demonstrate the first objective assessment of gait characteristics in patients with SIJ dysfunction undergoing minimally invasive posterior SIJ fusion.

Epidemiology of Low Back Injuries in National Collegiate Athletic Association (NCAA) Athletes: Results From the NCAA Injury Surveillance Program Between 2009-10 and 2018-19

BACKGROUND

Regular epidemiological investigations are needed to investigate factors associated with low back injuries (LBIs) in National Collegiate Athletic Association (NCAA) sports and to inform injury prevention and rehabilitation.

PURPOSE

To describe the epidemiology of LBIs in NCAA sports.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Exposure and LBI data collected in the NCAA Injury Surveillance Program during the 2009-10 through 2018-19 academic years were analyzed. Injury counts, rates, and proportions were described by sport, sex, event type (competition, practice), season segment, time loss (>1 day), history (recurrent, new), chronicity, injury mechanism, diagnosis, and activity. Injury rate ratios (IRRs) were used to evaluate differential injury rates, and injury proportion ratios (IPRs) were used to assess differential injury distributions. Effect estimates (IRRs, IPRs) with 95% CIs excluding 1.0 were deemed statistically significant.

RESULTS

During the study period, 2629 LBIs from 12,213,285 athlete-exposures (AEs) were reported to the NCAA Injury Surveillance Program (2.15 LBIs per 10,000 AEs). Rates were highest in women's gymnastics (5.39 per 10,000 AEs), men's tennis (3.39 per 10,000 AEs), and women's volleyball (3.38 per 10,000 AEs). Among sex-comparable sports, rates were higher in men's (compared with women's) basketball and cross country. Competition injury rates were >2 times as high as practice rates in men's sports; no difference was found in injury rates by event type in women's sports. Chronic LBIs were more prevalent in women's sports (compared with men's) (IPR = 1.51; 95% CI, 1.29-1.76), as were recurrent injuries (IPR = 1.24; 95% CI, 1.05-1.46).

CONCLUSION

Overall, LBI rates were similar in men's sports and women's sports; injuries were most often attributed to noncontact and overuse. LBI rates across event type varied by sport, with notable differences in women's sports. Future research into LBI risk factors and prevention programs that emphasize proper technique, training, and recovery, especially in practice settings, could be beneficial to reducing the burden of lumbar spine injuries in NCAA athletes.

Diagnostic values and relevant factors of lumbar posterior lesions in axial spondyloarthritis

OBJECTIVES

To compare the lumbar posterior lesions between axial spondyloarthritis (axSpA) and lumbar disc herniation (LDH) patients, then their diagnostic value and related factors were evaluated.

METHODS

This cross-sectional study included axSpA patients from January 2020 to September 2023. They were classified as ankylosing spondylitis (AS) and non-radiographic axSpA (nr-axSpA) individuals. Canada-Denmark magnetic resonance imaging (MRI) scoring system was used to assess the defects of the lumbar spine. Receiver operating characteristic curve analysis was utilized to determine the value of distinguishing nr-axSpA. Linear regression analyses were adopted to find the relevant factors for lumbar posterior lesions.

RESULTS

Ninety-six AS, 98 nr-axSpA, and 108 LDH patients were included. The Canada-Denmark scores were greater in axSpA patients, AS in particular. Furthermore, lumbar posterior lesions can distinguish AS, nr-axSpA, and LDH. Besides, lumbar posterior lesions were positively related to the similar MRI changes in their adjacent structures, but were inversely associated with the other abnormalities.

CONCLUSIONS

Lumbar posterior lesions were more serious in axSpA patients. These alterations had value in distinguishing axSpA. Lumbar posterior defects were related to their adjacent components, and they may not fully follow the MRI changing pattern of vertebral bodies and sacroiliac joints.

Sacroiliac Joint: Function, Pathology, Treatment, and Contribution to Outcomes in Spine and Hip Surgery

➢ Low back pain has a lifetime incidence of up to 84% and represents the leading cause of disability in the United States; 10% to 38% of cases can be attributed to sacroiliac joint (SIJ) dysfunction as an important pain generator.➢ Physical examination of the SIJ, including >1 provocation test (due to their moderate sensitivity and specificity) and examination of adjacent joints (hip and lumbar spine) should be routinely performed in all patients presenting with low back, gluteal, and posterior hip pain.➢ Radiographic investigations including radiographs, computed tomography, and magnetic resonance imaging with protocols optimized for the visualization of the SIJs may facilitate the diagnosis of common pathologies.➢ Intra-articular injections with anesthetic can be helpful in localizing the source of low back pain. Over-the-counter analgesics, physiotherapy, intra-articular injections, radiofrequency ablation, and surgery are all management options and should be approached from the least invasive to the most invasive to minimize the risks of complications.➢ Lumbar fusion surgery predisposes patients to more rapid SIJ degeneration and can also result in more rapid degenerative changes in the hip joints, especially with SIJ fusion.➢ Hip surgery, including hip arthroplasty and preservation surgery, is not a risk factor for SIJ degeneration, although reduced outcomes following hip surgery can be seen in patients with degenerative SIJ changes.

Clinical information on imaging referrals for suspected or known axial spondyloarthritis: recommendations from the Assessment of Spondyloarthritis International Society (ASAS)

OBJECTIVES

This study aims to establish expert consensus recommendations for clinical information on imaging requests in suspected/known axial spondyloarthritis (axSpA), focusing on enhancing diagnostic clarity and patient care through guidelines.

MATERIALS AND METHODS

A specialised task force was formed, comprising 7 radiologists, 11 rheumatologists from the Assessment of Spondyloarthritis International Society (ASAS) and a patient representative. Using the Delphi method, two rounds of surveys were conducted among ASAS members. These surveys aimed to identify critical elements for imaging referrals and to refine these elements for practical application. The task force deliberated on the survey outcomes and proposed a set of recommendations, which were then presented to the ASAS community for a decisive vote.

RESULTS

The collaborative effort resulted in a set of six detailed recommendations for clinicians involved in requesting imaging for patients with suspected or known axSpA. These recommendations cover crucial areas, including clinical features indicative of axSpA, clinical features, mechanical factors, past imaging data, potential contraindications for specific imaging modalities or contrast media and detailed reasons for the examination, including differential diagnoses. Garnering support from 73% of voting ASAS members, these recommendations represent a consensus on optimising imaging request protocols in axSpA.

CONCLUSION

The ASAS recommendations offer comprehensive guidance for rheumatologists in requesting imaging for axSpA, aiming to standardise requesting practices. By improving the precision and relevance of imaging requests, these guidelines should enhance the clinical impact of radiology reports, facilitate accurate diagnosis and consequently improve the management of patients with axSpA.

CT-guided joint cavity release for postpartum sacroiliac joint pain management: an evaluation of its efficacy, safety, and clinical outcomes

Objective

The central aim of this study was to evaluate the safety and effectiveness of Computed Tomography (CT)-guided joint cavity release in treating patients suffering from postpartum sacroiliac joint pain.

Methods

A retrospective analysis was conducted on a sample of 37 patients who presented with postpartum sacroiliac joint pain and underwent CT-guided sacroiliac joint release treatment at The Affiliated Hospital of North Sichuan Medical College. General clinical attributes of the patients were recorded, and the intensity of their pain before and after the operation was compared using the Numeric Pain Rating Scale (NRS). The effectiveness of the surgical treatment was assessed using the Modified MacNab criteria. The functional status of the sacroiliac joint at 3-and 6-month intervals post-operation was examined, and any complications related to surgery were documented.

Results

The follow-up period was completed by all patients, with the successful implementation of CT-guided unilateral/bilateral sacroiliac joint release undertaken in 37 patients. Patient reported pain, as measured by the Numeric Pain Rating Scale (NRS), was considerably reduced postoperatively with scores showing significant decrement from 7.14 ± 1.23 preoperatively to 1.26 ± 0.53 at 1 week, 1.86 ± 0.62 at 1 month, 1.92 ± 0.48 at 3 months, and 1.97 ± 0.61 at 6 months postoperatively, respectively (p < 0.05). The comprehensive record of treatment response rates, interpreted as excellent and good, were consistent, standing at 100% (37/37), followed by 97.30% (35/37) and concluding with 91.89% (33/37). The Oswestry Disability Index (ODI) scores reflecting the patient's perceived level of disability prior to the surgery, and at 3 and 6 month intervals post-surgery were 45.12 ± 6.01, 18.14 ± 2.23, and 14.25 ± 2.15, respectively, demonstrating a significant improvement in postoperative scores when compared with preoperative scores (p < 0.05). The surgeries conducted were devoid of any complications such as bleeding, infection, cardiovascular or cerebrovascular incidents, or decline in joint functionality in any of the patients.

Conclusion

Evidently, CT-guided joint cavity release presents as an effective therapeutic approach for the management of postpartum sacroiliac joint pain, enhancing quality of life and preserving patient safety.

Incidence and risk factors of new-onset sacroiliac joint pain after spinal surgery: a systematic review and meta-analysis

Purpose

A systematic review and meta-analysis for incidence and risk factors of new-onset sacroiliac joint pain (SIJP) after spinal surgery aimed to provide evidence-based medical references for its early prevention, timely intervention, and appropriate treatment.

Methodology

The protocol of the systematic review and meta-analysis was registered in the International Prospective Register of Systematic Review (PROSPERO) with the PROSPERO ID (CRD42023463177). Relevant studies were searched to January 2024 from the databases of PubMed, Embase, Cochrane Library, and Web of Science, and the types of studies were cohort studies, case-control studies, and cross-sectional studies. Study quality was assessed using the Newcastle-Ottawa Scale (NOS) and the Cross-Sectional/Prevalence Study Quality recommended by the Agency for Healthcare Research and Quality (AHRQ). Two authors conducted studies search, data extraction, and quality assessment independently. Meta-analyses were done using Stata 14.0 software.

Results

Twelve observational studies with 3,570 spinal surgery patients were included. Ten were case-control studies, one was a cross-sectional study, and another was a cohort study, all of which were of moderate quality and above. The results of the meta-analysis showed that the incidence of new-onset SIJP after spinal surgery was 9.40%; females, no. of surgical segments, fusion to the sacrum, and postoperative pelvic tilt (PT) were significantly associated with the new-onset SIJP after spinal surgery. Meta-analyses for preoperative and postoperative controls of spondylopelvic parameters showed that postoperative lumbar lordosis (LL) in the SIJP group and postoperative LL and sacral slope (SS) of patients in the NoSIJP group had significant differences from preoperative.

Conclusion

Available evidence suggests that an increased risk of new-onset SIJP after spinal surgery is associated with sex, multi-segmental surgery, fusion to the sacrum, and greater postoperative PT.

Acupotomy combined with Korean medicine treatment in a patient with acute sacroiliac pain unresponsive to conventional therapy: A case report

RATIONALE

Acute injury to the sacroiliac joint (SIJ) can result from high-energy external forces that cause a combination of axial loading and sudden rotational movements, resulting in severe pain that cannot be relieved by regular nonsteroidal anti-inflammatory drugs. The treatment includes injections of steroids and local anesthetics to reduce pain and promote healing. Here, we report the case of a patient with acute sacroiliac pain who did not respond to conventional injection therapy.

PATIENT CONCERNS

A 58-year-old male patient who did not exercise regularly experienced pain in his left groin and difficulty walking while kicking on his right leg. He received two injections and manual therapy at a local orthopedic clinic; however, his symptoms did not improve despite taking painkillers.

DIAGNOSES

Radiographic images showed no abnormalities. After confirming the cause of onset, pain pattern, physical examination, and tenderness, the patient was diagnosed with an acute SIJ sprain (static blood).

INTERVENTIONS

At the first visit, a single acupotomy was performed on the seven treatment points identified during the physical examination, and immediate improvement in symptoms was confirmed. From then on, Korean medicine (KM) treatments, such as acupuncture, cupping, chuna, and bee venom pharmacopuncture, were performed.

OUTCOMES

Immediately after acupotomy, groin pain improved by 80 %, gait immediately normalized, and the patient showed no symptoms at the 9th visit.

LESSONS

For SIJ-type groin pain that does not respond to existing treatments, immediate relief is achieved after a single acupotomy at the exact treatment point. Therefore, in the future, the importance of identifying a precise treatment point for SIJ pain should be recognized, and the use of Korean medicine treatment techniques, including acupotomy, should be considered.

Biomechanical, biochemical, and histological characterization of sacroiliac joint cartilage in the Yucatan minipig

Although the sacroiliac (SI) joint can be a source of lower back and buttock pain, no comprehensive characterization studies on SI cartilage have been conducted. Using the minipig as a large animal model, this study conducted the first biomechanical, biochemical, and histological characterization of SI joint cartilage. Because previous literature has reported that sacral cartilage and iliac cartilage within the SI joint are histologically distinct, concomitantly it was expected that functional properties of the sacral cartilage would differ from those of the iliac cartilage. Creep indentation, uniaxial tension, biochemical, and histological analyses were conducted on the sacral and iliac cartilage of skeletally mature female Yucatan minipigs (n = 6-8 for all quantitative tests). Concurring with prior literature, the iliac cartilage appeared to be more fibrous than the sacral cartilage. Glycosaminoglycan content was 2.2 times higher in the sacral cartilage. The aggregate modulus of the sacral cartilage was 133 ± 62 kPa, significantly higher than iliac cartilage, which only had an aggregate modulus of 51 ± 61 kPa. Tensile testing was conducted in both cranial-caudal and ventral-dorsal axes, and Young's modulus values ranged from 2.5 ± 1.5 MPa to 13.6 ± 1.5 MPa, depending on anatomical structure (i.e., sacral vs. iliac) and orientation of the tensile test. The Young's modulus of sacral cartilage was 5.5 times higher in the cranial-caudal axis and 2.0 times higher in the ventral-dorsal axis than the iliac cartilage. The results indicate that the sacral and iliac cartilages are functionally distinct from each other. Understanding the distinct differences between sacral and iliac cartilage provides insight into the structure and function of the SI joint, which may inform future research aimed at repairing SI joint cartilage.

The true pelvic volume change with various corrective osteotomy techniques for exstrophy-epispadias complex spectrum: the value of computer-assisted virtual surgery

Pelvic osteotomies are essential to approximate widened symphysis pubis in the exstrophy-epispadias complex, yet it is unknown which osteotomy type has the greatest effect on pelvic volume. We therefore used virtual surgery to study pelvic volume change with anterior, oblique, and posterior iliac osteotomies. Preoperative CT scans of two cloacal and one classic bladder exstrophy patients were used. Simulations were free-hand or constrained to keep minimal strain in the sacrospinous SSL and sacrotuberous STL ligaments. Changes in inter-pubic distance, pelvic volume, SSL and STL strains were measured. Mean pelvic volume decreased by 10% with free hand compared to 23% with constrained simulations ( P  = 0.171) and decreased by 7% with posterior, 17% with diagonal and 26% with horizontal osteotomies ( P  = 0.193). SSL and STL were strained by 20% and 26%, respectively, with free-hand simulations. A statistically significant moderate positive correlation was found between the decrease in inter-pubic distance and reduction in pelvic volume (r = 0.6, P  = 0.004). Mean pelvic volume decreased 0.05, 0.37 and 0.62% for each mm of pubic symphysis approximation with posterior, diagonal and horizontal osteotomies, respectively. Differences in effect on pelvic volume were identified between the osteotomies using virtual surgery which predicted residual diastasis in actual cloacal exstrophy surgical reconstructions. Oblique osteotomies are a compromise, avoiding difficulties with posterior osteotomies and excessive pelvic volume reduction with horizontal osteotomies. Understanding how osteotomy type affects pelvic morphology with virtual surgery may be an effective adjunct to pre-operative planning in exstrophy spectrum.

Prevalence of sacroiliac joint fusion in females and males depending on parity status

OBJECTIVES

Previous research shows that sacroiliac (SI) joint fusion is age and sex dependent. Older individuals-specifically starting in the fifth or sixth decade of life-are more likely to develop SI fusion. Females have a lower frequency of SI joint fusion than males, perhaps due to pregnancy or parturition. This study examines the relationship between SI joint fusion with both sex and parity status in females. The issue is whether the prevalence of SI fusion in nulliparous females is more similar to that of males or parous females.

MATERIALS AND METHODS

The sample consists of 46 nulliparous females, 119 parous females, and 158 males from the William M. Bass Donated Skeletal Collection. Ages of the individuals ranged from 50 to 89 years. Sex, age, and parity status were self-reported.

RESULTS

The frequency of SI joint fusion is significantly different among males (13.29%), nulliparous females (6.52%), and parous females (0.84%). Pairwise comparison of the three groups for SI joint fusion shows that parous females and males are significantly different, but nulliparous females are nonsignificantly different from parous females and males.

DISCUSSION

Parity status does not appear to be a factor in the sexually dimorphic nature of SI joint fusion in this sample. Rather, biomechanical and hormonal factors may have a greater contribution to higher rates of SI joint fusion in males than females.

Biomechanical Predictors of Sacroiliac Joint Uptake on Single-Photon Emission Computed Tomography/Computed Tomography

OBJECTIVE

Single-photon emission computed tomography/computed tomography (SPECT/CT) is an emerging imaging modality that identifies sites of heightened bone metabolism in response to increased stresses. The relationship between sacroiliac (SI) joint radiotracer uptake and anatomic biomechanical parameters is poorly understood.

METHODS

Adult patients with SPECT/CT scans performed at our institution between 2021 and 2023 for the workup of low back pain were included. Patient charts were reviewed for demographic factors including age, gender, and prior thoracolumbar fusion history. Biomechanical spinopelvic parameters were measured from standing scoliosis radiographs. SPECT/CT scans were reviewed for uptake at the SI joint. Patients were stratified into 2 cohorts; patients with SI uptake greater than iliac crest uptake were designated "hot," whereas those with less or equal uptake were labeled "cold."

RESULTS

One-hundred and sixty patients met inclusion criteria. Patients were slightly more male (55%) with average age 55 ± 14.9 years. Sixty-eight patients (43%) had evidence of increased SI activity. Interrater reliability showed substantial agreement (kappa = 0.62). The hot cohort demonstrated greater pelvic incidence (54.8 ± 14.0 degrees vs. 51.0 ± 11.0 degrees, P = 0.031) and pelvic tilt (20.8 ± 9.5 degrees vs. 18.4 ± 8.6 degrees, P =0.047) compared with the cold cohort. Patients were otherwise similar between cohorts (P > 0.05).

CONCLUSIONS

Increased pelvic incidence and pelvic tilt angles are associated with SPECT/CT uptake at the SI joint, which may reflect altered biomechanics at the spinopelvic junction. SPECT/CT may be a valuable tool to assess SI degeneration. Future studies are warranted to better characterize the clinical applications of these findings.

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.

Assessing the Impact of Radiographic Realignment on Adult Spinal Deformity Patients with Sacroiliac Joint Pain at Presentation

Background: Adult spinal deformity (ASD) patients with concurrent sacroiliac joint (SIJ) pain are susceptible to worse postoperative outcomes. There is scarce literature on the impact of ASD realignment surgery on SIJ pain. Methods: Patients undergoing ASD realignment surgery were included and stratified by the presence of SIJ pain at the baseline (SIJP+) or SIJ pain absence (SIJP-). Mean comparison tests via ANOVA were used to assess baseline differences between both cohorts. Multivariable regression analyses analyzed factors associated with SIJ pain resolution/persistence, factoring in BMI, frailty, disability, and deformity. Results: A total of 464 patients were included, with 30.8% forming the SIJP+ cohort. At the baseline (BL), SIJP+ had worse disability scores, more severe deformity, higher BMI, higher frailty scores, and an increased magnitude of lower limb compensation. SIJP+ patients had higher mechanical complication (14.7 vs. 8.2%, p = 0.024) and reoperation rates (32.4 vs. 20.2%, p = 0.011) at 2 years. SIJP+ patients who subsequently underwent SI fusion achieved disability score outcomes similar to those of their SIJ- counterparts. Multivariable regression analysis revealed that SIJP+ patients who were aligned in the GAP lordosis distribution index were more likely to report symptom resolution at six weeks (OR 1.56, 95% CI: 1.02-2.37, p = 0.039), 1 year (OR 3.21, 2.49-5.33), and 2 years (OR 3.43, 2.41-7.12). SIJP- patients who did not report symptom resolution by 1 year and 2 years were more likely to demonstrate PI-LL > 5° (OR 1.36, 1.07-2.39, p = 0.045) and SVA > 20 mm (OR 1.62, 1.24-1.71 p = 0.017). Conclusions: SIJ pain in ASD patients may result in worsened pain and disability at presentation. Symptom resolution may be achieved in affected patients by adequate postoperative lumbar lordosis restoration.

The Role of Orthoses in Chronic Axial Spinal Conditions

PURPOSE OF REVIEW

Bracing represents a prevalent conservative, non-surgical approach used in the management of chronic spinal conditions such as spondylosis, degenerative disc disease, and spondylolisthesis. A wide variety of orthoses are available to aid in addressing cervical, thoracic, lumbar, thoracic, and SI joint pain. In this review, we aim to comprehensively examine brace types with their current applications and implications of usage.

RECENT FINDINGS

There are multiple cervical bracing options, such as soft and rigid collars, to assist in managing acute trauma and chronic degenerative conditions. The review highlights the nuanced decision-making process between hard and soft collars based on the severity of bone or ligamentous injury and neurological findings. Orthoses for low back pain are commonly used. The review highlights the challenges of chronic neck and lower back pain, emphasizing the importance of clinicians exploring all treatment strategies including braces which can improve function and reduce pain.

Diagnosis and treatment of acute inflammatory sacroiliitis in pregnant or post-partum women: a systematic review of the current literature

The aim of the present study is to systematically review the current literature about diagnosis and treatment of acute inflammatory sacroiliitis in pregnant or post-partum women. A systematic search was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data about clinical presentation, diagnosis methods and treatment strategies were retrieved from included studies and reported in a table. After screening, five studies on 34 women were included; they were all affected by acute inflammatory sacroiliitis. Clinical examination and magnetic resonance imaging were used to confirm diagnosis. In four studies, patients were treated with ultrasound-guided sacroiliac injections of steroids and local anesthetics, while one study used only manual mobilization. Clinical scores improved in all patients. Ultrasound-guided injections proved to be a safe and effective strategy for inflammatory sacroiliitis treatment during pregnancy or post-partum.

Injective Treatments for Sacroiliac Joint Pain: A Systematic Review and Meta-analysis

Background

The most effective injective treatment approach for sacroiliac joint (SIJ) pain remains unclear. Aim of this study was to quantify the safety and effectiveness of the available injective strategies to address SIJ pain.

Methods

A systematic review and meta-analysis of the literature was conducted on PubMed, Scopus, and Embase databases from inception until January 2023. Inclusion criteria were studies written in English, comparative and non-comparative studies regardless of the minimum follow-up, and case series on SIJ injections. Safety and efficacy of the different injection therapies for the SIJ were quantified. A meta-analysis was conducted on the available data of the documented injective therapies. The "Checklist for Measuring Quality" by Downs and Black was used to assess the risk of bias and the quality of papers.

Results

The literature search retrieved 43 papers (2431 patients): 16 retrospective case series, 2 retrospective comparative studies, 17 prospective case series, 3 prospective comparative studies, and 5 randomized controlled trials. Of the selected studies, 63% examined the effect of steroid injections, 16% of PRP injections, while 21% reported other heterogeneous treatments. The failure rate was 26% in steroid injections and 14% in PRP injections. The meta-analysis showed a statistically significant reduction in pain with the VAS score for both steroids and PRP: steroids improvement at mid-term 3.4 points (p < 0.05), at long-term 3.0 (p < 0.05), PRP improvement at mid-term 2.2 (p = 0.007), at long-term 2.3 points of the VAS pain scale (p = 0.02).

Conclusions

Steroids are the most documented injective approach, with studies showing an overall safety and effectiveness. Still, the high number of failures underlined by some studies suggest the need for alternative procedures. Early PRP data showed promise, but the limitations of the current literature do not allow to clearly define the most suitable injective approach, and further studies are needed to identify the best injective treatment for SIJ patients.

Voice Quality of Life and Musculoskeletal Symptoms of Pregnant Women

INTRODUCTION

Quality of life in terms of voice and musculoskeletal symptoms can be affected, especially at the end of pregnancy when major physical changes occur.

OBJECTIVE

To analyze the results of vocal self-assessment and musculoskeletal symptoms of pregnant women in the second and third trimester.

METHODS

Forty-nine pregnant women in the second and third trimester aged between 18 and 40years were examined using the Nordic Musculoskeletal Questionnaire and the Voice-Related Quality of Life Questionnaire. The data were statistically analyzed using the R environment (R Core Team, 2019) with parametric (Student's t, chi-square, and Wald) and nonparametric (Mann-Whitney and Wilcoxon) tests, taking into account a nominal significance level of 5%.

RESULTS

Voice-related quality of life: mean total score and socio-emotional domain significantly within the normal values; physical domain significantly below the normal value; larger number of pregnant women significantly below the normal value in the physical domain. Nordic Musculoskeletal Questionnaire: most of the examined aspects showed a significant negative response; there was a positive significance for the presence of pain and tingling in the lower back; pregnant women with musculoskeletal complaints and impairments showed a significant decrease in the three domains of voice-related quality of life, mainly in the physical domain.

CONCLUSION

Pregnant women showed a deterioration in the physical domain of voice-related quality of life and the presence of pain and tingling in the lower back. Pregnant women who had discomfort and musculoskeletal impairments also showed a deterioration in voice-related quality of life, mainly in the physical domain.

Systematic Review and Meta-Analysis of the Effectiveness of Radiofrequency Ablation of the Sacroiliac Joint

PURPOSE OF REVIEW

To evaluate the effectiveness of radiofrequency neurotomy in managing sacroiliac joint pain utilizing a systematic review with meta-analysis of randomized controlled trials (RCTs) and observational studies.

RECENT FINDINGS

The prevalence of sacroiliac joint pain is estimated at around 25% of low back pain cases, and its diagnosis lacks a gold standard. Treatments include exercise therapy, injections, ablation, and fusion, with variable effectiveness. COVID-19 altered utilization patterns of interventions, including sacroiliac joint procedures, and the evidence for these interventions remains inconclusive. Recently, Medicare has issued its local coverage determinations (LCDs) in the United States, which provides noncoverage of sacroiliac joint radiofrequency neurotomy. Additionally, a recent systematic review of sacroiliac joint injections showed Level III or fair evidence. The sacroiliac joint, a critical axial joint linking the spine and pelvis, contributes to low back pain. Its complex innervation pattern varies among individuals. Sacroiliac joint dysfunction, causing pain and stiffness, arises from diverse factors.The present systematic review and meta-analysis aimed to evaluate radiofrequency neurotomy's effectiveness for sacroiliac joint pain management by applying rigorous methodology, considering both RCTs and observational studies. Despite methodological disparities, the evidence from this review, supported by changes in pain scores and functional improvement, suggests Level III evidence with fair recommendation for radiofrequency neurotomy as a treatment option. The review's strengths include its comprehensive approach and quality assessment. However, limitations persist, including variations in criteria and technical factors, underscoring the need for further high-quality studies in real-world scenarios.

Impact of Sacroiliac Belt Utilization on Balance in Patients with Low Back Pain

Background

Low back pain (LBP) is a common problem which can affect balance and, in turn, increase fall risk. The aim of this investigation was to evaluate the impact of a Sacroiliac Belt (SB) on balance and stability in patients with LBP.

Methods

Subjects with LBP and without LBP ("Asymptomatic") were enrolled. Baseline balance was assessed using the Berg Balance Scale. In a counterbalanced crossover design, LBP and Asymptomatic subjects were randomized to one of two groups: 1) start with wearing the SB (Serola Biomechanics, Inc.) followed by not wearing the SB or 2) start without wearing the SB followed by wearing the SB. For subjects in both groups, dynamic balance was then assessed using the Star Excursion Balance Test (SEBT) with each leg planted.

Results

Baseline balance was worse in LBP subjects (Berg 51/56) than Asymptomatic subjects (Berg 56/56) (p<0.01). SB significantly improved SEBT performance in LBP subjects regardless of which leg was planted (p<0.01). SB positively impacted Asymptomatic subjects' SEBT performance with the left leg planted (p=0.0002).

Conclusion

The Serola Sacroiliac Belt positively impacted dynamic balance for subjects with low back pain. Further research is needed to examine additional interventions and outcomes related to balance in patients with back pain, and to elucidate the mechanisms behind improvements in balance related to sacroiliac belt utilization.

A literature review of biomechanical studies on physiological and pathological sacroiliac joints: Articular surface structure, joint motion, dysfunction and treatments

BACKGROUND

Sacroiliac joints are affected by mechanical environments; the joints are formed under mechanical stimulation, receive impact of walking between the upper and lower parts of the bodies and can be a cause of pain due to non-physiological loads. However, there are so far very few studies that reviewed biomechanics of physiological and pathological sacroiliac joints. This review article aims to describe the current sacroiliac joint biomechanics.

METHODS

Previous original papers have been summarized based on three categories: articular surface structure, sacroiliac joint motion and sacroiliac joint dysfunction and treatments.

FINDINGS

Although the articular surface morphologies vary greatly from individual to individual, many researchers have tried to classify the joints into several types. It has been suggested that the surface morphologies may not change regardless of joint dysfunction, however, the relationship between the joint structure and pain are still unclear. The range of sacroiliac joint motion is demonstrated to be less than 1 mm and there is no difference between physiological and pathological joints. The sacroiliac joint absorbs shock within the pelvis by the joint structures of pelvic morphology, ligaments and fat tissues. The morphology and motion of the sacroiliac joints may be optimized for upright bipedal walking.

INTERPRETATION

There is no doubt that pelvic mechanical environments affect pain induction and treatment; however, no one has yet provided a concrete explanation. Future research could help develop treatments based on sacroiliac joint biomechanics to support joint function.

EMERGENCY DEPARTMENT INTRAARTICULAR CORTICOSTEROID INJECTION FOR SACROILIAC JOINT DYSFUNCTION

BACKGROUND

Sacroiliac joint (SIJ) dysfunction is a common but underrecognized source of low back pain (LBP). With provocative testing, emergency physicians can diagnose SIJ dysfunction and begin appropriate treatment in the emergency department (ED).

DISCUSSION

For patients with significant pain from SIJ dysfunction, ultrasound-guided SIJ injection of anesthetic and corticosteroid can reduce patients' pain considerably.

CONCLUSIONS

For patients who are good candidates for SIJ injection, emergency physicians can begin treatment in the ED, before the patient follows up with a specialist.

Cooled radiofrequency ablation versus standard medical management for chronic sacroiliac joint pain: a multicenter, randomized comparative effectiveness study

INTRODUCTION

Low back pain is the leading cause of disability worldwide, with sacroiliac joint pain comprising up to 30% of cases of axial lower back pain. Conservative therapies provide only modest relief. Although placebo-controlled trials show efficacy for sacral lateral branch cooled radiofrequency ablation, there are no comparative effectiveness studies.

METHODS

In this randomized, multicenter comparative effectiveness study, 210 patients with clinically suspected sacroiliac joint pain who obtained short-term benefit from diagnostic sacroiliac joint injections and prognostic lateral branch blocks were randomly assigned to receive cooled radiofrequency ablation of the L5 dorsal ramus and S1-S3 lateral branches or standard medical management consisting of pharmacotherapy, injections and integrative therapies. The primary outcome measure was mean reduction in low back pain score on a 0-10 Numeric Rating Scale at 3 months. Secondary outcomes included measures of quality of life and function.

RESULTS

3 months post-treatment, the mean Numeric Rating Scale pain score for the cooled radiofrequency ablation group was 3.8±2.4 (mean reduction 2.5±2.5) compared with 5.9±1.7 (mean reduction 0.4±1.7) in the standard medical management group (p<0.0001). 52.3% of subjects in the cooled radiofrequency ablation group experienced >2 points or 30% pain relief and were deemed responders versus 4.3% of standard medical management patients (p<0.0001). Comparable improvements favoring cooled radiofrequency ablation were noted in Oswestry Disability Index score (mean 29.7±15.2 vs 41.5+13.6; p<0.0001) and quality of life (mean EuroQoL-5 score 0.68±0.22 vs 0.47±0.29; p<0.0001).

CONCLUSIONS

In patients with sacroiliac joint pain, cooled radiofrequency ablation provided statistically superior improvements across the spectrum of patient outcomes compared with standard medical management.

TRIAL REGISTRATION NUMBER

NCT03601949.

Hip-sacroiliac joint-spine syndrome in total hip arthroplasty patients

This study is designed to compare the extent of sacroiliac joint (SIJ) degeneration at total hip arthroplasty (THA) for two pathologies: osteoarthritis of the hip (OA) and osteonecrosis of the femoral head (ON). We also assessed the prevalence of SIJ degeneration in patients with lumbar spondylolisthesis or degenerative scoliosis. A total of 138 hips from 138 patients (69 OA and 69 ON) were assessed in this study, including 66 hips affected by OA secondary to developmental dysplasia of the hip. The degenerative changes in the SIJ and lumbar spine were evaluated prior to THA using radiographs and computed tomography (CT) scans, showing 9 instances of spondylolisthesis and 38 of degenerative scoliosis. The OA group exhibited longer duration from onset to surgery than the ON group. The OA group also included more cases with significant pelvic obliquity (3 degrees or more) and with significant increases in SIJ sclerosis and irregularities. Patients with lumbar spondylolisthesis or degenerative scoliosis were significantly more likely to have SIJ irregularities. The prevalence of SIJ degeneration was higher in cases of THA for OA than for ON. This study also suggests the possibility of Hip-SIJ-Spine syndrome in THA patients with OA.

Exploring health and illness perceptions to identify the perceived cause of pregnancy-related pelvic girdle pain. A mixed-methods study among primiparous women in The Netherlands

BACKGROUND

Pregnancy-related pelvic girdle pain (PPGP) is common and considered a multifactorial condition with biomechanical and psychosocial contributions. The patient's perceived cause is an important aspect of illness perceptions, and a strong predictor of self-management and healthcare utilization. It is unknown what causal beliefs primiparae hold regarding PPGP.

OBJECTIVE

To explore and describe health and illness perceptions among primiparae towards PPGP and its cause.

DESIGN

Exploratory, convergent parallel mixed-methods.

SETTING

At the participants' homes.

PARTICIPANTS

Sixteen primiparae with and without PPGP.

FINDINGS

Primiparae with and without PPGP held comparable causal beliefs about PPGP. PPGP was described as the result of hormonal softening and loosening of the pelvis, and failure of the muscular system to compensate for that. Women who experienced similar physical symptoms attributed them differently, leading to different coping strategies. Interestingly, maternal healthcare providers reinforced the unidimensional- and predominantly biomechanical view when women sought healthcare.

CONCLUSION

The causal mechanism of PPGP held by the women was not determined by their lived experience. It was primarily based on the concept of inevitable hormonal softening of the pelvis. This biomechanical belief is based on theories that are not in line with current knowledge of PPGP and contemporary pain science, yet they were reinforced by maternity healthcare providers.

IMPLICATIONS FOR PRACTICE

Healthcare seeking behavior is influenced by illness beliefs. Maternity healthcare providers may play a key role in providing reassurance and addressing the multifactorial nature of PPGP when providing care and support to pregnant women.

The Sacroiliac Joint: A Current State-of-the-Art Review

» The sacroiliac joint (SIJ) is a common cause of low back pain and should be included in the differential diagnosis.» Nonoperative treatment of sacroiliac pain is always the first line of therapy; however, when it is unsuccessful and becomes chronic, then recurrent nonoperative treatment becomes expensive.» Surgical treatment is cost-effective in appropriately selected patients. High-quality clinical trials have demonstrated statistically and clinically significant improvement compared with nonsurgical management in appropriately selected patients.» Spinal fusion to the sacrum increases degeneration of the SIJ and frequency of SIJ pain.

Exploring 3D Pelvis Orientation: A Cross-Sectional Study in Athletes Engaged in Activities with and without Impact Loading and Non-Athletes

Female athletes subjected to various types of impact loading, especially over a long period of time, may experience changes in their pelvic orientation, which may affect their sport performance and increase the likelihood of injury. The aim of the present study was to determine whether female athletes involved in high-impact loading sports (HILS), odd-impact loading sports (OILS), and repetitive non-impact loading sports (NILS) demonstrate changes in pelvis orientation compared to non-athletes (NATH). Pelvic orientation was determined using Euler/Cardan angles, calculated from the coordinates of the right, and left anterior superior iliac spines and pubic symphysis via a novel method. Two-way ANOVA tests showed significant differences between groups for pelvis position in the frontal plane (p < 0.05), with HILS and OILS demonstrating greater pelvic obliquity compared to NILS athletes and NATH. Significant main effects were also obtained for directions within the sagittal plane (p < 0.001). Significant within-group differences were observed in sagittal pelvic position among female athletes engaged in NILS (p < 0.01) and non-athletes (NATH) (p < 0.05), with a greater anterior pelvic tilt compared to posterior. Our findings suggest that pelvis orientation in female athletes across sports is influenced by sport-specific impact loads, potentially affecting performance and injury occurrence.

Radiological Insights into Sacroiliitis: A Narrative Review

Sacroiliitis is the inflammation of the sacroiliac joint, the largest axial joint in the human body, contributing to 25% of lower back pain cases. It can be detected using various imaging techniques like radiography, MRI, and CT scans. Treatments range from conservative methods to invasive procedures. Recent advancements in artificial intelligence offer precise detection of this condition through imaging. Treatment options range from physical therapy and medications to invasive methods like joint injections and surgery. Future management looks promising with advanced imaging, regenerative medicine, and biologic therapies, especially for conditions like ankylosing spondylitis. We conducted a review on sacroiliitis using imaging data from sources like PubMed and Scopus. Only English studies focusing on sacroiliitis's radiological aspects were included. The findings were organized and presented narratively.

The sacroiliac joint: An original and highly sensitive tool to highlight altered bone phenotype in murine models of skeletal disorders

Bone disorders may affect the skeleton in different ways, some bones being very impaired and others less severely. In translational studies using murine models of human skeletal diseases, the bone phenotype is mainly evaluated at the distal femur or proximal tibia. The sacroiliac joint (SIJ), which connects the spine to the pelvis, is involved in the balanced transfer of mechanical energy from the lumbar spine to the lower extremities. Because of its role in biomechanical stress, the SIJ is a region of particular interest in various bone diseases. Here we aimed to characterize the SIJ in several murine models to develop a highly reliable tool for studying skeletal disorders. We performed a 12-month in vivo micro-computed tomography (micro-CT) follow-up to characterize the SIJ in wild-type (WT) C57BL/J6 mice and compared the bone microarchitecture of the SIJ and the distal femur at 3 months by micro-CT and histology. To test the sensitivity of our methodology, the SIJ and distal femur were evaluated at 3 and 6 months, in 2 murine models of skeletal disorder, X-linked hypophosphatemia (Hyp mice) and HLA-B27 transgenic mice and compared to WT mice. A multimodal analysis was performed, using a combination of microCT and histological analysis. With the Hyp model, the SIJ displayed more bone microarchitecture alterations than the distal femur. Hyp mice showed a significant reduction in trabecular bone at both the distal femur and sacral slope as compared with WT mice, with a significant positive correlation between trabecular bone parameters of the distal femur and sacral side of the SIJ. Furthermore, trabecular bone parameters (Bone Volume/Total Volume (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N), trabecular pattern factor (Tb.Pf)) were significantly increased compared to femoral parameters at the SIJ. The sacral articular cortical bone, which is indicative of osteoarticular lesions, was altered in Hyp mice. Interestingly, in accordance to previous studies, HLA-B27 transgenic mice did not show any osteoarticular lesions as compared with WT mice. Cortical bone parameters (thickness, porosity), as well as scoring performed with double blinding, did not show difference between the 2 genotypes. The characterization and evaluation of the SIJ surface appears very sensitive to emphasize alterations of bone and joint. The SIJ may represent a valuable tool to investigate both bone and local osteoarticular alterations in murine models of skeletal disorders and might be a relevant site for assessing the response to treatment of chronic bone diseases.

Incidence and Predictive Factors of New Onset Postoperative Sacroiliac Joint Pain After Posterior Lumbar Fusion Surgery for Degenerative Lumbar Disease

Introduction

To explore the incidence and predictive factors of new onset postoperative sacroiliac joint pain (PSJP) after posterior lumbar fusion surgery for degenerative lumbar disease.

Methods

Three hundred and sixty-seven patient medical records from January 2020 to December 2021 were retrieved. The patients were divided into two groups: PSJP group and N-PSJP (non-postoperative sacroiliac joint pain group). To investigate potential risk factors for PSJP, HU value (Hounsfield unit value) was assessed on CT scans. ImageJ software was used to assess the fat and muscle of the lumbar multifidus muscle (LMM) in the axial MRI image, the red area was marked as fat and the rest were muscles to calculate the ratio of fatty infiltration. Patient characteristics, surgical variables and radiographic parameters were analyzed statistically.

Results

Twenty of 367 patients were diagnosed with PJSP at postoperative follow-up. Patients with PSJP presented with significantly higher HU value. For surgical variables, PSJP patients received more operations including distal fusion level at sacrum than the N-PSJP group. For radiographic parameters, most of the patients in the PSJP group had more severe fatty atrophic muscle in the LMM compared to the N-PSJP group. There was no statistically significant difference between the two groups in preoperative and postoperative lumbar lordosis (LL), angle of lumbar lordosis of fixed lumbar vertebrae (FV-LL), pelvic incidence (PI), sacrum slope (SS). The bivariate logistic regression model revealed preoperative fat infiltration rate of the LMM, and higher HU value were independently associated with PSJP.

Conclusion

PSJP for degenerative lumbar disease was 5.4%, the predictive factors included preoperative severe infiltration of LMM, distal fusion level at sacrum and higher HU value.

Differences in imaging and clinical characteristics are associated with higher rates of decompression-fusion versus decompression-alone in women compared to men for lumbar degenerative spondylolisthesis

PURPOSE

The goals were to ascertain if differences in imaging/clinical characteristics between women and men were associated with differences in fusion for lumbar degenerative spondylolisthesis.

METHODS

Patients had preoperative standing radiographs, CT scans, and intraoperative fluoroscopic images. Symptoms and comorbidity were obtained from patients; procedure (fusion-surgery or decompression-alone) was obtained from intraoperative records. With fusion surgery as the dependent variable, men and women were compared in multivariable logistic regression models with clinical/imaging characteristics as independent variables. The sample was dichotomized, and analyses were repeated with separate models for men and women.

RESULTS

For 380 patients (mean age 67, 61% women), women had greater translation, listhesis angle, lordosis, and pelvic incidence, and less diastasis and disc height (all p ≤ 0.03). The rate of fusion was higher for women (78% vs. 65%; OR 1.9, p = 0.008). Clinical/imaging variables were associated with fusion in separate models for men and women. Among women, in the final multivariable model, less comorbidity (OR 0.5, p = 0.05), greater diastasis (OR 1.6, p = 0.03), and less anterior disc height (OR 0.8, p = 0.0007) were associated with fusion. Among men, in the final multivariable model, opioid use (OR 4.1, p = 0.02), greater translation (OR 1.4, p = 0.0003), and greater diastasis (OR 2.4, p = 0.0002) were associated with fusion.

CONCLUSIONS

There were differences in imaging characteristics between men and women, and women were more likely to undergo fusion. Differences in fusion within groups indicate that decisions for fusion were based on composite assessments of clinical and imaging characteristics that varied between men and women.

Biomechanics in the onset and severity of spondyloarthritis: a force to be reckoned with

Increasing evidence suggests that there is a pivotal role for physical force (mechanotransduction) in the initiation and/or the perpetuation of spondyloarthritis; the review contained herein examines that evidence. Furthermore, we know that damage and inflammation can limit spinal mobility, but is there a cycle created by altered spinal mobility leading to additional damage and inflammation?Over the past several years, mechanotransduction, the mechanism by which mechanical perturbation influences gene expression and cellular behaviour, has recently gained popularity because of emerging data from both animal models and human studies of the pathogenesis of ankylosing spondylitis (AS). In this review, we provide evidence towards an appreciation of the unsolved paradigm of how biomechanical forces may play a role in the initiation and propagation of AS.

Lumbar Disc Degeneration Affects the Risk of Rod Fracture Following PSO; A Finite Element Study

STUDY DESIGN

Finite element (FE) study.

OBJECTIVE

Pedicle subtraction osteotomy (PSO) is a surgical method to correct sagittal plane deformities. In this study, we aimed to investigate the biomechanical effects of lumbar disc degeneration on the instrumentation following PSO and assess the effects of using interbody spacers adjacent to the PSO level in a long instrumented spinal construct.

METHODS

A spinopelvic model (T10-pelvis) with PSO at the L3 level was used to generate 3 different simplified grades of degenerated lumbar discs (mild (Pfirrmann grade III), moderate (Pfirrmann grade IV), and severe (Pfirrmann grade V)). Instrumentation included eighteen pedicle screws and bilateral primary rods. To investigate the effect of interbody spacers, the model with normal disc height was modified to accommodate 2 interbody spacers adjacent to the PSO level through a lateral approach. For the models, the rods' stress distribution, PSO site force values, and the spine range of motion (ROM) were recorded.

RESULTS

The mildly, moderately, and severely degenerated models indicated approximately 10%, 26%, and 40% decrease in flexion/extension motion, respectively. Supplementing the instrumented spinopelvic PSO model using interbody spacers reduced the ROM by 22%, 21%, 4%, and 11% in flexion, extension, lateral bending, and axial rotation, respectively. The FE results illustrated lower von Mises stress on the rods and higher forces at the PSO site at higher degeneration grades and while using the interbody spacers.

CONCLUSIONS

Larger and less degenerated discs adjacent to the PSO site may warrant consideration for interbody cage instrumentation to decrease the risk of rod fracture and PSO site non-union.

Sex-specific diagnostic efficacy of MRI in axial spondyloarthritis: challenging the 'One Size Fits All' notion

OBJECTIVES

Sex-specific differences in the presentation of axial spondyloarthritis (axSpA) may contribute to a diagnostic delay in women. The aim of this study was to investigate the diagnostic performance of MRI findings comparing men and women.

METHODS

Patients with back pain from six different prospective cohorts (n=1194) were screened for inclusion in this post hoc analysis. Two blinded readers scored the MRI data sets independently for the presence of ankylosis, erosion, sclerosis, fat metaplasia and bone marrow oedema. Χ2 tests were performed to compare lesion frequencies. Contingency tables were used to calculate markers for diagnostic performance, with clinical diagnosis as the standard of reference. The positive and negative likelihood ratios (LR+/LR-) were used to calculate the diagnostic OR (DOR) to assess the diagnostic performance.

RESULTS

After application of exclusion criteria, 526 patients (379 axSpA (136 women and 243 men) and 147 controls with chronic low back pain) were included. No major sex-specific differences in the diagnostic performance were shown for bone marrow oedema (DOR m: 3.0; f: 3.9). Fat metaplasia showed a better diagnostic performance in men (DOR 37.9) than in women (DOR 5.0). Lower specificity was seen in women for erosions (77% vs 87%), sclerosis (44% vs 66%), fat metaplasia (87% vs 96%).

CONCLUSION

The diagnostic performance of structural MRI markers is substantially lower in female patients with axSpA; active inflammatory lesions show comparable performance in both sexes, while still overall inferior to structural markers. This leads to a comparably higher risk of false positive findings in women.

Salvage of failed direct lateral sacroiliac joint fixation using a new percutaneous lateral-oblique transfixation technique with two variable-threaded screws: a multicenter case report of three cases

Background

The direct lateral trans-gluteal muscle splitting transiliac approach was popularized to fixate the sacroiliac joint (SIJ) using three cannulated triangular titanium implants (TTIs) wedges. Publications support efficacy of the direct lateral approach but a paucity of literature to help surgeons revise these implants when they fail. Intuitively the implants can be removed but require an open incision and dissection through the gluteal muscles and scar tissue which can lead to muscle and neurovascular injuries. Our objective was to evaluate the clinical outcome, measured by patient-reported Visual Analog Score (VAS), of three patients who had failed direct lateral SIJ fusions each using three implants and describe a revision technique using a new percutaneous lateral-oblique transfixation technique with two variable-threaded screws while preserving the original implants.

Case Description

Two separate orthopedic spine surgeons at different hospitals performed the technique using two SacroFuse® screws for SIJ revision fusion in three patients who had clinical symptoms and radiographic findings of SIJ pseudoarthrosis after direct lateral approach. One 61 years old male patient had a previous surgery with three lateral threaded screw implants. Two females with ages 47 and 40 years old had three TTI wedges. Follow-up from 10 to 26 months. Patients discharged home the same day. Mean procedure time of 20 minutes with blood loss less than five cc. Incision size was approximately 1 inch. Each patient had a 12 mm × 60 mm and a 12 mm × 50 mm screw filled with NanoFuse Biologics synthetic bioactive glass and demineralized bone matrix. Prior implants were left in place. There was an 89% decrease in mean VAS score of 9.5 to 1.

Conclusions

This is a clinically valuable report because until now there was no reconstructive surgery to revise direct lateral implants other than removal with potential neurovascular risks. This is the first article to demonstrate a lateral-oblique transfixation technique with two variable-threaded screws for successful salvage of SIJ pseudoarthrosis after direct lateral fixation without implant removal. The Sacrix technique achieved immediate stability and long-term fusion documented on computed tomography (CT) scan as early as 6 months.

The effects of topping-off instrumentation on biomechanics of sacroiliac joint after lumbosacral fusion

BACKGROUND

Lumbar/lumbosacral fusion supplemented with topping-off devices has been proposed with the aim of avoiding adjacent segment degeneration proximal to the fusion construct. However, it remains unclear how the biomechanics of the sacroiliac joint (SIJ) are altered after topping-off surgery. The objective of this study was to investigate the biomechanical effects of topping-off instrumentation on SIJ after lumbosacral fusion.

METHODS

The validated finite element model of an intact lumbar spine-pelvis segment was modified to simulate L5-S1 interbody fusion fixed with a pedicle screw system. An interspinous spacer, Device for Intervertebral Assisted Motion (DIAM), was used as a topping-off device and placed between interspinous processes of the L4 and L5 segments. Range of motion (ROM), von-Mises stress distribution, and ligament strain at SIJ were compared between fusion (without DIAM) and topping-off (fusion with DIAM) models under moments of four physiological motions.

RESULTS

ROM at the left and right SIJs in the topping-off model was higher by 26.9% and 27.5% in flexion, 16.8% and 16.1% in extension, 18.8% and 15.8% in lateral bending, and 3.7% and 7.4% in axial rotation, respectively, compared to those in the fusion model. The predicted stress and strain data showed that under all physiological loads, the topping-off model exhibited higher stress and ligament strain at the SIJs than the fusion model.

CONCLUSIONS

Motion, stress, and ligament strain at SIJ increase when supplementing lumbosacral fusion with topping-off devices, suggesting that topping-off surgery may be associated with higher risks of SIJ degeneration and pain than fusion alone.

Minimally Invasive Postero-Inferior Sacroiliac Joint Fusion: Surgical Technique and Procedural Details

(1) Background: Minimally invasive sacroiliac joint (SIJ) fusion is the preferred surgical intervention to treat chronically severe pain associated with SIJ degeneration and dysfunction. (2) Methods: This paper details the ten-step surgical procedure associated with the postero-inferior approach using the PsiF™ DNA Sacroiliac Joint Fusion System. (3) Results: The posterior surgical approach with an inferior operative trajectory (postero-inferior) utilizes easily identifiable landmarks to provide the safest, most direct access to the articular joint space for transfixing device placement. Implanting the device through the subchondral bone provides maximum fixation and stabilization of the joint by utilizing an optimal amount of cortical bone-implant interface. Approaching the joint from the inferior trajectory also places the implant perpendicular to the S1 endplate at a "pivot point" near the sacral axis of rotation, which addresses the most significant motion of the joint. (4) Conclusions: Further observational data from real-world clinical use are encouraged to further validate this procedure as the surgical preference for minimally invasive SIJ fusion.

The bone marrow side of axial spondyloarthritis

Spondyloarthritis (SpA) is characterized by the infiltration of innate and adaptive immune cells into entheses and bone marrow. Molecular, cellular and imaging evidence demonstrates the presence of bone marrow inflammation, a hallmark of SpA. In the spine and the peripheral joints, bone marrow is critically involved in the pathogenesis of SpA. Evidence suggests that bone marrow inflammation is associated with enthesitis and that there are roles for mechano-inflammation and intestinal inflammation in bone marrow involvement in SpA. Specific cell types (including mesenchymal stem cells, innate lymphoid cells and γδ T cells) and mediators (Toll-like receptors and cytokines such as TNF, IL-17A, IL-22, IL-23, GM-CSF and TGFβ) are involved in these processes. Using this evidence to demonstrate a bone marrow rather than an entheseal origin for SpA could change our understanding of the disease pathogenesis and the relevant therapeutic approach.

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.

Chronic Lower Back Pain in Weight Lifters: Epidemiology, Evaluation, and Management

» Chronic lower back pain (LBP) is common in both nonathletes and weight lifters, but the diagnosis and treatment should be approached differently in these 2 populations based on the unique movement patterns causing the pain.» Injury rates of weight lifters are far less than those of contact sports, ranging from 1.0 to 4.4 injuries per 1,000 workout hours. However, the lower back was consistently one of the top 2 injury sites for weight lifters, accounting for anywhere from 23% to 59% of all injuries. LBP was most often associated with the squat or deadlift.» Guidelines for evaluating general LBP are applicable to weight lifters, including a thorough history and physical examination. However, the differential diagnosis will change based on the patient's lifting history. Of the many etiologies of back pain, weight lifters are most likely to be diagnosed with muscle strain or ligamentous sprain, degenerative disk disease, disk herniation, spondylolysis, spondylolisthesis, or lumbar facet syndrome.» Traditional recommended therapies include nonsteroidal anti-inflammatory drugs, physical therapy, and activity modification, which are often insufficient to resolve pain and prevent injury recurrence. Because most athletes will want to continue to lift weights, lifting-specific behavior modifications focused on improved technique and correcting mobility and muscular imbalances are important aspects of management in this patient population.