Ankylosing Spondylitis

Cervical spine fracture-dislocation in patients with ankylosing spondylitis and severe thoracic kyphosis: Application of halo vest before and during surgical management

Cervical spine fracture-dislocation in patients with ankylosing spondylitis (AS) and severe thoracic kyphosis is extremely unstable. This study was performed to investigate the efficacy and safety of halo vest application before and during surgery for these patients. We retrospectively analyzed the case histories, operations, neurologic outcomes, follow-up data, and imaging records of 25 patients with AS and severe thoracic kyphosis who underwent surgical treatment of cervical fracture-dislocation in our department from 2008 to 2019. A halo vest was used to reduce and immobilize the fractured spinal column ends before and during surgery. The neurologic injury was evaluated using the American Spinal Injury Association (ASIA) impairment scale score, visual analog scale (VAS) score, and Japanese Orthopaedic Association (JOA) score before and after the operation. Twenty-two patients achieved closed anatomical reduction; two achieved successful reduction and one underwent failed reduction after halo vest application. No fracture site displacement occurred after movement into the prone position. No patients developed secondary neurological deterioration. The mean Cobb angle of thoracic kyphosis was 69.0° ± 12.3°. All patients underwent posterior or combined anterior-posterior surgery. The ASIA grade improved significantly (P < 0.01). The mean VAS and JOA scores also increased significantly after the operation (14.6 ± 3.0 vs. 10.4 ± 4.3 and 0.5 ± 0.6 vs. 4.6 ± 1.9, respectively; P < 0.01). One patient died 3 weeks after the operation. No other severe complications occurred. All patients had reached solid bony fusion by the 12-month follow-up. Use of a halo vest before and during the operation is safe and effective in patients with AS and severe thoracic kyphosis who develop cervical fracture-dislocation. This technique makes positioning, awake nasoendotracheal intubation, nursing, and the operation more convenient. It can also provide satisfactory reduction and rigid immobilization and prevent secondary neurologic deterioration.

Management of cervical fractures in ankylosing spondylitis: anterior, posterior or combined approach?

INTRODUCTION

Ankylosing spondylitis (AS) can lead to an increased risk of cervical fractures.

SOURCES OF DATA

A systematic review was undertaken using the keywords 'ankylosing spondylitis', 'spine fractures', 'cervical fractures', 'surgery' and 'postoperative outcomes' on Medline, Pubmed, Google Scholar, Ovid and Embase, and the quality of the studies included was evaluated according to the Coleman Methodology Score.

AREAS OF AGREEMENT

Surgery ameliorates neurological function in patients with unstable AS-related cervical fractures. The combined anterior/posterior and the posterior approaches are more effective than the anterior approach.

AREAS OF CONTROVERSY

The optimal approach, anterior, posterior or combined anterior/posterior, for the management of AS related cervical fractures has not been defined.

GROWING POINTS

Open reduction and internal fixation allows avoiding worsening and enhances neurological function in AS patients with cervical fractures.

AREAS TIMELY FOR DEVELOPING RESEARCH

Adequately powered randomized trials with appropriate subjective and objective outcome measures are necessary to reach definitive conclusions.

Predictive factors of radiographic progression in ankylosing spondylitis

BACKGROUND/AIMS

The course of ankylosing spondylitis (AS) is rather variable, and the factors that predict radiographic progression remain largely obscure. In this study, we tried to determine the clinical factors and laboratory measures that are useful in predicting the radiographic progression of patients with AS.

METHODS

In 64 consecutive patients with AS, we collected radiographic and laboratory data over 3 years. Radiographic data included images of the sacroiliac (SI) and hip joints and laboratory data included areas under the curve (AUC) of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), alkaline phosphatase (ALP), and hemoglobin (Hb). We investigated associations among changes in radiographic scores, initial clinical manifestations and laboratory measurements.

RESULTS

Changes in scores for the SI joint and lumbar spine did not correlate with AUC for ESR, CRP, or ALP. AUC for Hb did not significantly correlate with radiographic progression in any joint. Patients with hip arthritis at the initial visit showed significantly higher radiographic score changes after 3 years in the SI and hip joint compared to those without hip arthritis. Patients who had shoulder arthritis as the initial manifestation had significantly increased AUCs for ESR and CRP compared to those without shoulder arthritis. However, at 3 years, the change of the lumbar spine score was significantly higher in patients without shoulder arthritis.

CONCLUSIONS

These results indicate that hip arthritis at presentation is a useful clinical marker for predicting the structural damage to the SI and hip joint, and suggest that initial shoulder arthritis correlates with slower radiographic progression of the lumbar spine.

The information needs of people living with ankylosing spondylitis: a questionnaire survey

BACKGROUND

Today, health care is patient-centred with patients more involved in medical decision making and taking an active role in managing their disease. It is important that patients are appropriately informed about their condition and that their health care needs are met. We examine the information utilisation, sources and needs of people with ankylosing spondylitis (AS).

METHODS

Participants in an existing AS cohort study were asked to complete a postal or online questionnaire containing closed and open-ended questions, regarding their information access and needs. Participants were stratified by age and descriptive statistics were performed using STATA 11, while thematic analysis was performed on open-ended question narratives. Qualitative data was handled in Microsoft Access and explored for emerging themes and patterns of experiences.

RESULTS

Despite 73% of respondents having internet access, only 49% used the internet to access information regarding AS. Even then, this was only infrequently. Only 50% of respondents reported accessing written information about AS, which was obtained mainly in specialist clinics. Women were more likely than men to access information (63% (women) 46% (men)) regardless of the source, while younger patients were more likely to use online sources. The main source of non-written information was the rheumatologist. Overall, the respondents felt there was sufficient information available, but there was a perception that the tone was often too negative. The majority (95%) of people would like to receive a regular newsletter about AS, containing positive practical and local information. Suggestions were also made for more information about AS to be made available to non-specialist medical professionals and the general public.

CONCLUSIONS

There appears to be sufficient information available for people with AS in the UK and this is mostly accessed by younger AS patients. Many patients, particularly men, choose not to access AS information and concerns were raised about its negative tone. Patients still rely on written and verbal information from their specialists. Future initiatives should focus on the delivery of more positive information, targeting younger participants in particular and increasing the awareness in the general population and wider non-specialist medical community.

IL-23A, IL-23R, IL-17A and IL-17R polymorphisms in different psoriatic arthritis clinical manifestations in the northern Italian population

To investigate the genetic variability of IL-17A, IL17-RA, IL-23A and IL-23R genes on an in-depth phenotypically characterized northern Italian Psoriatic arthritis (PsA) case-control cohort, in search for associations specific to different PsA clinical sub-phenotypes. We examined 118 patients with PsA according to CASPAR criteria (mean age 57 ± 13, female 38.4 %, mean disease duration 13.9 ± 8.6 years, peripheral disease 83.8 %, axial manifestations 34.5 %, radiological erosive disease 49 %) compared with 248 controls of the same ethnic origin matched for age and sex. The presence of axial disease was defined by the clinical axial involvement and/or the presence of radiological alteration consistent with spondyloarthropathy according to New York criteria. The presence of peripheral disease (arthritis and/or enthesitis) was defined only on clinical basis. A total of 40 SNPs, mapping within the genes mentioned above, were genotyped in both groups and used to perform association analyses by subdividing the PsA sample into subgroups according to different clinical manifestations on the basis of axial and peripheral involvements. No differences between patients and controls were found in the distribution of the IL-17A, IL17-RA, IL-23A and IL-23R genes allelic variants. Comparing patients with axial disease versus those without, we found that axial manifestations were significantly associated with the presence of IL-23R rs12401432 GG homozygosity (26.8 % vs. 5.3 %, p corr = 0.019, OR 2.63 [95 % CI 1.13-6.16]). No differences in distribution of the allelic variants were found comparing patients with versus those without peripheral disease or patients with versus without radiological peripheral erosions. In PA patients of northern Italian origin, IL-17A, IL17-RA, IL-23A and IL-23R genes allelic variants are not associated with disease susceptibility. However, a strong association with the IL-23RA rs12401432 GG genotype is associated with axial involvement of the disease.

Fracture of the lower cervical spine in patients with ankylosing spondylitis: Retrospective study of 19 cases

INTRODUCTION

Controversy exists surrounding optimal treatment of cervical spine fractures secondary to ankylosing spondylitis (AS).

HYPOTHESIS

The anterior approach is an effective surgical technique for these fractures and can be used to correct the AS-induced cervical-thoracic kyphosis.

MATERIALS AND METHODS

This continuous, retrospective series between 1990 and 2010 included 19 patients aged 33 to 84 years who presented with a lower cervical spine fracture in the context of AS. The average follow-up was 45 months. Sixteen of these patients were surgically treated using an anterior approach and anterior fixation. In five patients without any neurological deficit, their cervical-thoracic kyphosis was corrected during the same surgery. Regional kyphosis was measured before the surgery, immediately after the surgery and at the last follow-up.

RESULTS

Five deaths occurred; these were all patients with post-traumatic complete quadriplegia. Most the incomplete neurological problems improved (66%). In no cases did the neurological condition worsen. Among the 16 patients operated with the anterior approach, two patients also required an additional procedure with a posterior approach because of a persistent neurological deficit. The fractures in the operated patients who survived (14 patients) had healed within an average 4-month delay (range 3-7 months), without worsening of the kyphosis at final follow-up. In the five cases where the kyphosis was corrected, the correction averaged 26° (range 18-36°); there were no neurological complications.

DISCUSSION

Based on these results, we suggest using the anterior approach to perform internal fixation as a treatment for cervical fractures secondary to AS and to correct the cervical-thoracic kyphosis in patients without neurological deficits.

LEVEL OF EVIDENCE

Level IV - retrospective study.

Vertebral locking lesion following cervical spine fracture in ankylosing spondylitis

Spine fractures in patients with ankylosing spondylitis frequently extend to all 3 columns, which can lead to displacement and deformity with severe instability. Cervical spine fractures occasionally cause severe kyphotic deformities, such as chin-on-chest deformities. In such cases, the patients typically exhibit a chronic progression of hyperkyphosis after the traumatic event. This article describes a unique case of ankylosing spondylitis associated with an acute chin-on-chest deformity following a spine fracture due to a vertebral locking lesion.A 60-year-old man fell while walking and sustained a compression fracture of the C6 vertebra. Two weeks later, the patient acutely developed an inability to raise his head, difficulties with chewing and swallowing, and a horizontal gaze. Radiographs demonstrated a severe kyphosis in the cervical spine with a locking lesion between the anterior wall of the C5 and C6 vertebrae. The patient also presented with neurological impairment in his hands. Because the anterior approach to the spine was anatomically impossible, halo traction was initially applied under a close observation of neurological symptoms. Three days after halo traction, release of the vertebral locking lesion and realignment of the spine were seen. The patient subsequently underwent spinal fusion using a combined anterior-posterior approach.Postoperatively, neurological dysfunction improved, and solid fusion was confirmed at 6 months. In cases of acute kyphotic deformity following cervical spine fracture in ankylosing spondylitis patients, halo traction followed by circumferential spine fusion is a safe and effective approach for improving the alignment and stability of the spine.

ANKH and susceptibility to and severity of ankylosing spondylitis

OBJECTIVE

Unconfirmed reports describe association of ankylosing spondylitis (AS) with several candidate genes including ANKH. Cellular export of inorganic pyrophosphate is regulated by the ANK protein, and mutant mice (ank/ank), which have a premature stop codon in the 3' end of the ank gene, develop severe ankylosis. We tested the association between single-nucleotide polymorphisms (SNP) in these genes and susceptibility to AS in a population of patients with AS. We investigated the role of these genes in terms of functional (BASFI) and metrological (BASMI) measures, and the association with radiological severity (mSASSS).

METHODS

Our study was conducted on 355 patients with AS and 95 ethnically matched healthy controls. AS was defined according to the modified New York criteria. Four SNP in ANKH (rs27356, rs26307, rs25957, and rs28006) were genotyped. Association analysis was performed using Cochrane-Armitage and linear regression tests for dichotomous and quantitative variables. Analyses of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), BASFI, and mSASSS were controlled for sex and disease duration.

RESULTS

None of the 4 markers showed significant single-locus disease associations (p > 0.05), suggesting that ANKH was not a major determinant of AS susceptibility in our population. No association was observed between these SNP and age at symptom onset, BASDAI, BASFI, BASMI, or mSASSS.

CONCLUSION

These results confirm data in white Europeans that ANKH is probably not a major determinant of susceptibility to AS. ANKH polymorphisms do not markedly influence AS disease severity, as measured by BASMI and mSASSS.

Bilateral synchronous total hip arthroplasty for ankylosed hips

PURPOSE

We investigated the effect of bilateral total hip replacement (THR) for patients with ankylosed hip joints caused by late ankylosing spondylitis (AS) and to discuss its related pre- and postoperative problems.

METHODS

Data of 12 patients with ankylosed hip joints caused by late AS who underwent THR (24 hips) were reviewed. Each patient had both hips replaced at the same time. We assessed joint pain, range of motion (ROM) and Harris hip score (HHS) to determine postoperative results.

RESULTS

Mean follow-up was 4.2 years; all hip-joint function improved, and flexion deformity was corrected. Flexion ranges were 75-105°(average 84. 4°) extension 10°~20°(average 18. 7°). HHS ranged from 15.21 points preoperation to 86.25 points postoperation. No patient experienced hip pain postoperatively, and presurgery knee and lower back pain were clearly relieved postoperatively.

CONCLUSION

Bilateral THR is an effective treatment for the ankylosed hip joint caused by late ankylosing spondylitis. When considering this procedure, attention to related pre- and postoperative problems must be considered.

Surgical outcome after spinal fractures in patients with ankylosing spondylitis

Background

Ankylosing spondylitis is a rheumatic disease in which spinal and sacroiliac joints are mainly affected. There is a gradual bone formation in the spinal ligaments and ankylosis of the spinal diarthroses which lead to stiffness of the spine.

The diffuse paraspinal ossification and inflammatory osteitis of advanced Ankylosing spondylitis creates a fused, brittle spine that is susceptible to fracture. The aim of this study is to present the surgical experience of spinal fractures occurring in patients suffering from ankylosing spondylitis and to highlight the difficulties that exist as far as both diagnosis and surgical management are concerned.

Methods

Twenty patients suffering from ankylosing spondylitis were operated due to a spinal fracture. The fracture was located at the cervical spine in 7 cases, at the thoracic spine in 9, at the thoracolumbar junction in 3 and at the lumbar spine in one case. Neurological defects were revealed in 10 patients. In four of them, neurological signs were progressively developed after a time period of 4 to 15 days. The initial radiological study was negative for a spinal fracture in twelve patients. Every patient was assessed at the time of admission and daily until the day of surgery, then postoperatively upon discharge.

Results

Combined anterior and posterior approaches were performed in three patients with only posterior approaches performed on the rest. Spinal fusion was seen in 100% of the cases. No intra-operative complications occurred. There was one case in which superficial wound inflammation occurred. Loosening of posterior screws without loss of stability appeared in two patients with cervical injuries.

Frankel neurological classification was used in order to evaluate the neurological status of the patients. There was statistically significant improvement of Frankel neurological classification between the preoperative and postoperative evaluation. 35% of patients showed improvement due to the operation performed.

Conclusion

The operative treatment of these injuries is useful and effective. It usually succeeds the improvement of the patients' neurological status. Taking into consideration the cardiovascular problems that these patients have, anterior and posterior stabilization aren't always possible. In these cases, posterior approach can be performed and give excellent results, while total operation time, blood loss and other possible complications are decreased.

Treatment of ankylosing spondylitis and extra-articular manifestations in everyday rheumatology practice

The SpAs are a group of overlapping, chronic, inflammatory rheumatic diseases including AS, a chronic inflammatory disease primarily affecting the SI joints. In addition to inflammatory back pain, AS patients are also more likely to experience extra-articular manifestations belonging to the SpA concept which can affect the eyes, the gastrointestinal tract and the skin and other related inflammatory conditions. This review focuses on current progress in treatment options in SpA with special emphasis on extra-articular features. TNF inhibition has demonstrated effectiveness in the treatment of AS symptoms and all currently available anti-TNF agents appear to have similar efficacy. However, the efficacy of anti-TNF agents varies in the treatment of extra-articular manifestations and comorbidities. Analyses of trials of anti-TNF agents in patients with AS have revealed significant reductions in the incidence of flares of uveitis and IBD with infliximab and adalimumab (uveitis only) treatment but not with etanercept. All three anti-TNF agents (infliximab, adalimumab, etanercept) have demonstrated efficacy in psoriasis (not associated with AS). When evaluating as to which agent to use in the treatment of AS, an important consideration is the overall well-being of the patient. This should include any additional inflammatory burden that manifests in other parts of the body, which may currently be subclinical. Based on current evidence, among TNF inhibitors, the monoclonal antibodies (infliximab and adalimumab) are more appropriate than etanercept if extra-articular manifestations or comorbid conditions are present or suspected. To date, infliximab appears to be the best studied agent with a wide spectrum of proven efficacy.

Complex Deformities of the Cervical Spine

Cervical deformities arise from a multitude of causes, including genetic, congenital, inflammatory, degenerative, and iatrogenic etiologies. They often require surgical intervention for treatment of pain, progressive structural decompensation, and neurologic deterioration. Although congenital and hereditary causes of cervical deformity require specialized attention to particular clinical features and operative considerations, postsurgical (iatrogenic) cervical deformity after surgery is the most common single cause. Appropriate treatment involves careful selection of conservative and aggressive measures and familiarity with advanced surgical techniques that allow for the safe correction of these challenging deformities. Flexible deformities can be managed with single-staged procedures, whereas fixed deformities require two-staged or even three-staged procedures. Staged surgery for fixed cervical deformities can achieve up to 28 degrees of angular correction and 31% translational correction.

Pulmonary abnormalities in ankylosing spondylitis: inspiratory and expiratory high-resolution CT findings in 17 patients

OBJECTIVE

The purpose of this study was to evaluate pulmonary manifestations of ankylosing spondylitis on inspiratory and expiratory high resolution CT.

MATERIAL AND METHODS

The study included 17 patients ranging from 40 to 62 years in age. Fifteen patients were male, and 8 were smokers. All patients underwent chest radiography and high-resolution CT. High-resolution CT was obtained using 1 or 2 mm collimation scans at 10-mm intervals at the end of maximal inspiration and at 3 cm intervals at the end of maximal expiration.

RESULTS

Pulmonary abnormalities were evident on chest radiography in 2 patients and on CT in 15 patients. The abnormalities on CT included evidence of airway disease in 14 (82%), interstitial abnormalities in 11 (65%), and emphysema in 6 (35%) patients. Airway abnormalities included bronchial wall thickening in 7 (41%), mosaic perfusion in 3 (18%), centrilobular nodules in 3, bronchiolectasis in 2, and air trapping on expiratory CT in 7 (41%) patients. Interstitial abnormalities included parenchymal bands in 7 (41%), intralobular linear opacities (n = 2), and 1 patient each with irregular thickening of interlobular septa, subpleural lines, and honeycombing.

CONCLUSION

The majority of patients with ankylosing spondylitis have airway and interstitial abnormalities evident on high-resolution CT. These abnormalities are usually mild and therefore seldom evident on the chest radiograph.

Mental health status and leisure-time physical activity contribute to fatigue intensity in patients with spondylarthropathy

OBJECTIVE

To examine the relationship between disease-related variables, leisure-time physical activity (LTPA), and mental health status with fatigue severity in patients with spondylarthropathy (SpA).

METHODS

Sixty-six SpA patients completed questionnaires assessing disease activity (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]), functional ability (Bath Ankylosing Spondylitis Functional Index), and health-related quality of life (Short Form 36). LTPA patterns, demographics, and disease-related data were obtained by interview. A clinical examination determined tender point count. Fatigue was assessed with the BASDAI fatigue item.

RESULTS

The mean BASDAI fatigue score was 5.5 (SD=2.7) with 59% of the sample obtaining a score > or =5. Disease activity, functional disability, and worse mental health contributed to greater fatigue (R2=0.56). The relationship between exercise duration and fatigue intensity was moderated by mental health status. For patients with poorer mental health scores, exercise did not influence fatigue severity. However, for patients reporting better mental health status, engaging in more LTPA decreased fatigue severity.

CONCLUSION

In addition to increased disease activity and functional disability, greater fatigue severity in SpA is associated with poorer mental health status. Integrating regular leisure physical activity into the comprehensive treatment of SpA may be useful for modulating fatigue.

Bath ankylosing spondylitis functional index (BASFI) evaluation of postoperative patients with OPLL

Although surgical decompression of the involved spinal cord achieves a good recovery of neurological conditions, one of the most important complaints of patients with ossification of the posterior longitudinal ligament (OPLL) is disability as a result of spinal immobility. The activities of daily living (ADL) of postoperative patients with OPLL were examined. To evaluate the ADL of postoperative patients with OPLL in the cervical spine, we utilized the Bath Ankylosing Spondylitis Functional Index (BASFI), one of the most widely used functional indexes for ankylosing spondylitis. We investigated consecutive cases that underwent surgery for OPLL of the cervical spine in our department from 1978 to 1998. The latest and postoperative scores were compared to the preoperative Japanese Orthopaedic Association (JOA) scores (range, 0-17) to assess neurological recovery. We also evaluated ADL at the latest follow-up, using BASFI scores. Significant recoveries of JOA scores were confirmed; however, 77% of patients complained of disability. In BASFI, questions that seemed to reflect spinal condition received low scores in the present study. BASFI scoring was not sufficient in the present form; however, it is one of the candidate functional indexes for evaluating ADL in postoperative patients with OPLL. Establishment of an ideal functional index for such evaluation is needed.

Pain in the rheumatic diseases. Practical aspects of diagnosis and treatment

Patients with rheumatic disease experience pain that can be intense, persistent, and disabling. This pain is frequently multifactorial in origin and has both central and peripheral components. Because of the array of conditions that can cause musculoskeletal pain, patient management must begin with a complete clinical assessment that identifies possible etiologies and measures objective findings against subjective complaints. Especially in patients with known rheumatic disease, the possibility of concurrent pain of central origin must be considered and appropriate treatment given. By applying a comprehensive therapy plan of drugs, physical therapy, and patient education, significant benefits can often be achieved in this prevalent group of painful diseases.

Diagnosing the systemic associations of anterior uveitis

Up to one-half of patients with anterior uveitis suffer from related systemic diseases. The common associations are the seronegative arthropathies and, in children, juvenile chronic arthritis. Anterior uveitis may also occur in the context of sarcoidosis or Behçet's disease. Syphilis and tuberculosis remain a significant problem for specific populations and may be the cause of anterior uveitis in these groups. By thorough clinical history and the correct selection and interpretation of simple investigations, it is generally possible for the ophthalmologist to make or exclude a systemic diagnosis, predict the ocular prognosis and direct selected patients to the appropriate physician. Diseases that threaten the patient's wellbeing must certainly be recognized. In the present review we present a method for identifying the systemic associations of anterior uveitis.

Spinal cord injury occurring in patients with ankylosing spondylitis: a multicenter study

Treatment of spinal fractures causing paralysis in patients with ankylosing spondylitis is difficult. A multicenter concurrent study evaluated 59 patients--22 managed operatively and 37 nonoperatively. The two groups were compared for neurologic outcome, complications, mortality, and length of stay. The results indicated that patients in the nonoperative group had a significantly shorter length of stay and, therefore, a significantly lower cost of care. No other differences between operative and nonoperative groups were identified in regard to other outcome variables. Results of descriptive analyses of patient characteristics and treatment choices have significant implications for practitioners.

Treatment of kyphotic deformity in ankylosing spondylitis

This article reviews the available literature on the surgical options for the correction of kyphosis in ankylosing spondylitis and presents the radiologic appearance of the post-operative spine. In the postsurgical evaluation of the spine, the focus is on appreciation of the patterns of correction, early and late determination of angular correction, recognition of various complications (infection, nonunion, improper location, or breakage of hardware), and alertness to the possibility of complications at all levels of the spine.

Quantitative scintigraphy of the sacroiliac joints

The effects of age and laterality on sacroiliac (SI) to sacral indices and ratios were assessed in 62 patients. For the 14 controls, the left mean SI to sacral index was significantly higher than the right one. There was no correlation between age and SI to sacral ratio (= average of right and left index). The mean ratio in 36 patients with sacroiliitis and 12 patients with low back pain was not significantly different from that of the controls, with a clear overlap of indices between controls and sacroiliitis patients.

Psoriatic arthritis of the temporomandibular joints with ankylosis. Literature review and case reports

Psoriatic arthritis is currently defined as psoriasis associated with chronic, erosive inflammatory arthritis, which is seronegative for rheumatoid factor. A review of the etiology, pathogenesis, diagnosis, and treatment is accompanied by two unusual case reports of psoriatic arthritis affecting the temporomandibular joints with ankylosis.

Cauda equina syndrome of long-standing ankylosing spondylitis. Case report and review of the literature

Cauda equina syndrome as a neurological complication of long-standing ankylosing spondylitis was first reported in 1961. The syndrome is relatively uncommon and its pathophysiology is still poorly understood. Based on their experience with such a case, the authors review the clinical, electrographic, histological, and radiographic features of the syndrome, including the findings of magnetic resonance (MR) imaging. The addition of MR imaging to the evaluation of patients with ankylosing spondylitis and the cauda equina syndrome not only aids in the diagnosis of the syndrome but may also provide valuable insight into the pathophysiology of this condition.

The scintigraphy of sacroiliac joints. A comparison of 99mTc-DPD and 99mTc-MDP

The accumulation of 99mTc-methylene diphosphonate (99mTc-MDP) and 99mTc-dicarboxypropane diphosphonate (99mTc-DPD) in sacroiliac (si) joints was evaluated as a function of imaging time in 22 control patients and 5 patients with sacroiliitis. The controls were injected with either 99mTc-DPD or 99mTc-MDP (12 and 10 patients, respectively) and the patients with sacroiliitis with both agents within 5 days. Both the anterior and posterior views of the si joints were taken. The sacroiliac joint-to-sacrum (SI/S) ratio was calculated with the region of interest method. No statistically significant differences between these bone-seeking agents were found in the SI/S ratios of the control or the diseased patients. A clear overlap of indices (mean +/- SD) was found between the control patients and the patients with sacroiliitis. When the inflamed si joint was divided into three small adjacent areas and the SI/S ratios calculated for these areas, a statistically significant (P less than 0.001) increase in the SI/S ratio was noticed when compared with the SI/S ratio of the whole joint. Comparison of control patients and patients with sacroiliitis showed the most significant differences in the anterior views as well as in the P value: P less than 0.001 in all patients injected with 99mTc-DPD and in most patients injected with 99mTc-MDP. In the posterior views, the significance was less marked. In every case, the inflamed part of the si joint was visible in the anterior views. The background subtraction had the greatest effect on the SI/S ratio of anterior images, but in the posterior views no significance was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Progressive ankylosis in mice. An animal model of spondylarthropathy. I. Clinical and radiographic findings

To determine its similarity to human spondylarthropathies, we studied murine progressive ankylosis, a spontaneously occurring disorder of joints in mice. Clinically, peripheral joints were inflamed initially, then became ankylosed in a predictable sequence from distal to proximal. Forefeet were involved before hindfeet. Axial joint involvement produced severe spinal ankylosis. Extraarticular manifestations included balanitis and crusting skin lesions. Radiographically, bony erosions and calcification of articular and periarticular tissues were extensive, and vertebral syndesmophytes produced a "bamboo" spine. We conclude that progressive ankylosis is a systemic disease with many clinical and radiographic similarities to human spondylarthropathies, and it may represent a useful animal model for the study of the human diseases.

Follow-up study of Reiter's disease and reactive arthritis. Factors influencing the natural course and the prognosis

The acute clinical picture and long-term prognosis of 160 patients with Reiter's disease (RD), and 144 patients with reactive arthritis triggered by yersinia infection (YA), was analysed. Most of the patients with RD were men, while YA was as common among male and female patients. YA manifested in a third of patients as incomplete or complete RD. The long-term prognosis in RD was less favourable than in YA. Recurrent arthritis, development of chronic destructive arthritis and radiologic sacroiliitis were more frequent in RD than in YA. The presence of HLA-B27 was the major factor determining extra-articular inflammatory symptoms and the development of chronic problems.

The frequency of rheumatoid arthritis among relatives of probands with definite ankylosing spondylitis

We studied families of 23 unrelated HLA-B27 positive probands with definite ankylosing spondylitis to investigate the occurrence of rheumatoid arthritis. The prevalence of RA among these relatives was significant higher (2.91%; 0.02 less than p less than 0.05) than in the control group of 28 healthy individuals (1.02%). These data suggest an increased relative risk of RA in relatives of patients with AS.