Ochronotic arthropathy: the value of bone scintigraphy in alkaptonuria

We report the case of a 62 year old man diagnosed of alkaptonuria who was referred to our department to undergo bone scintigraphy for polyarthralgia. The patient had a history of pain in lumbar and thoracic spine, right shoulder and left knee. Bone scintigraphy showed multiple joint disease with increased uptake in both shoulders, knees and spine. Higher uptake stood out in painful right shoulder and left knee joints. Ochronotic arthropathy that is developed in alkaptonuric patients is a degenerative joint disease. X-ray studies in this patient showed marked degenerative arthrosis in knees and shoulders, without more intense involvement in the symptomatic joints. Lumbar spine X-rays showed intervertebral disk calcification with disk collapse and fusion of the vertebral bodies with relative sparing of sacroiliac joint, which is a classic feature of ochronotic arthropathy. This case highlights the utility of bone scintigraphy in the evaluation of joint involvement as well as its correlation with clinical course and potential usefulness in the follow-up of this disease.     

Radiographic and MRI findings in ochronosis

PURPOSE: Ochronotic arthropathy is the articular manifestation of alkaptonuria, a rare hereditary metabolic disease that leads to the deposition of homogentisic acid particularly in the joints where it causes articular degeneration and inflammation. We studied the radiological patterns of the disorder using both traditional X-rays both MRI and comparing the results obtained with the two techniques. MATERIALS AND METHODS: The study included five patients (4 males, 1 female, mean age 51 years); we studied the most frequently affected sites, the knee, the shoulder and the spine. As regards the conventional study we used a radiographic score which considered the state of the articular space and the presence of calcifications. MRI of the peripheral joints was performed on the most symptomatic site or, if asymptomatic, on the most severely affected site as established by radiography; in all cases T1- and T2-weighted sequences in the axial, sagittal and coronal planes were acquired. RESULTS: Both the X-ray and MRI study revealed the typical alterations of ochronosis in the cases with a known diagnosis: articular space narrowing up to osseous ankylosis, calcifications, osteophytosis, reactive sclerosis of the articular surfaces; MRI was however more accurate in identifying the alterations and revealing lesions not visible at conventional radiology, such as ligament lesions. In the case of newly diagnosed ochronotic arthropathy MRI proved valuable for its ability to detect alterations that are poorly appreciable at conventional radiology. CONCLUSIONS: Modern diagnostic imaging, above all MRI, allowed us to identify the peculiar characteristic features of ochronosis and is fundamental both for the diagnosis and for differentiating ochronosis from other articular disorders.     

Radiologic manifestations in alcaptonuria

Alcaptonuria is a rare, hereditary disorder of amino acid metabolism, secondary to lack of homogentisic acid oxydase. As a consequence, there is ex accumulation of homogentisic acid, which is excreted in the urine and deposited in the connective tissues. This deposition results in ochronotic pigmentation and arthropathy, of which some characteristic radiological findings are demonstrated.     

Neuropathic spinal arthropathy: CT and MR findings

The CT and magnetic resonance findings of neuropathic spinal arthropathy in a patient with long-standing complete post-traumatic paraplegia are reported. The arthropathy involved primarily the disk space between the 11th and 12th thoracic vertebrae. The CT changes included vertebral body sclerosis with foci of bone destruction, replacement of the disk space by a soft tissue mass containing bone fragments extending beyond the confines of the vertebral body margins, degenerative changes of the posterior joints, a partially calcified progressively enlarging paraspinal soft tissue mass, and calcification within the spinal canal.     

Roentgenologic and nuclear medicine findings in alkaptonuric ochronosis

In alkaptonuria, a recessively inherited disturbance of amino acid metabolism, deposits of oxydation products of homogentisinic acid result in the disease pattern of ochronosis. Due to the enhanced brittleness of the supporting and gliding tissue, ochronotic arthropathy develops at the vertebral column and later at the major joints with typical roentgenological changes especially in the intervertebral space and the intervertebral disk, as well as the adjacent vertebral bodies. The bone scintigram shows enhanced accumulation in the base and tectorial plates as well as in the adjacent sclerosing zones in the spongiosa of the affected vertebral bodies.     

Anatomy and pathology of the aging spine

The vertebral column is a complicated anatomical structure which is composed of the intervertebral discs and the vertebrae. Both components develop special degenerative changes and morphologic features during life. This paper first reviews the anatomical fundamentals and then describes the morphological features of the aging intervertebral disc and the subsequent osseous changes of the vertebral bodies and the zygapophyseal joints. The aging intervertebral disc is characterised by processes which are labeled as intervertebral chondrosis and intervertebral osteochondrosis. Often these processes are combined with typical dislocations of intervertebral disc tissue in an anterior or dorsolateral direction. The well known Schmorl's nodules must also be mentioned in this context. Furthermore calcification and ossification of the intervertebral disc tissue can take place. More severe processes lead to osseous changes of the vertebral bodies. In particular, an osteophytosis of the vertebral bodies can be established. These sturdy osteophytes are able to stiffen the vertebral column. Furthermore the arthrotic changes of the zygapophyseal joints are delineated in this paper. The special appearances of these changes are discussed according to the different and specialised regions of the vertebral column. The advanced degenerative changes of the zygapophyseal and uncovertebral joints of the cervical spine are of essential clinical interest because the compression of the vertebral artery or the narrowing of the intervertebral foramina by these processes may cause severe neurological symptoms. The arthrotic changes of the medial atlantoaxial joint, which lead to the crowned odontoid, and the pseudospondylolisthesis (so called M. Junghanns) of the lumbar spine must also be mentioned. It is the aim of this paper, not only to explain and review the degenerative changes, but to illustrate the anatomy and pathology of the aging spine on the basis of macerated osseous specimens in order to make radiological investigations and pictures more understandable and clear.     

Atypical vertebral Paget’s disease

A 40-year-old Mauritanian man consulted for back pain. A computed tomography of the spine showed patchy sclerosis of the fifth and seventh thoracic vertebral bodies with normal neural arch of T5 and sclerosis and hypertrophy of the neural arch of T7, as well as diffuse sclerosis of the T11 vertebral body with a normal neural arch. At MRI, low signal-intensity on T1-weighted images and high signal-intensity on T2-weighted images involved the whole T5 and T7 vertebrae and the vertebral body of T11. Working diagnoses included metastatic disease and lymphoma, and a biopsy of T7 and then T11 was carried out. Both showed pathological findings very suggestive of Paget’s disease. Since CT is usually the more specific radiological examination in vertebral Paget’s disease, we thought it could be useful to report this atypical CT presentation (patchy sclerosis of the vertebral body without diffuse bone texture changes and isolated involvement of the vertebral body) of vertebral Paget’s disease.     

脊柱嗜酸性肉芽肿的螺旋CT表现

目的探讨脊柱嗜酸性肉芽肿的CT表现。方法搜集经病理组织学证实的脊柱嗜酸性肉芽肿患者15例,所有病例均行CT平扫及矢状位重建。结果 15例共累及23个椎体,单发10例,多发5例,其中颈椎6个,胸椎10个,腰椎7个。23个病灶均位于椎体,其中3个同时累及附件,2个累及椎弓根。23个病灶CT表现为椎体不同程度骨质破坏,其中19个椎体压缩变扁,13个病灶周围硬化,9个病灶于椎旁形成软组织肿块,1个椎间隙变窄。结论认识脊柱嗜酸性肉芽肿的CT表现,密切结合临床症状及实验室检查,有助于提高诊断的准确性。     

Axial skeletal changes in paraplegics.

Two-hundred paraplegic men were studied to determine the nature of their axial skeletal changes. Forty-two per cent had sacro-iliac (SI) joint changes which varied from marginal blurring, erosion, sclerosis, and narrowing of the joint space (9%) to complete obliteration of the joints (33%). Radiographs of the thoracolumbar spine revealed syndesmophytes (9%), interspinous ossification (2%), intervertebral disk calcification (1.5%), and large osteophytes (2%). These changes had no relation to race, age (except spine changes), or paralysis level, but were related to the duration of the paralysis. The observed skeletal changes mimic HLA-B27 arthropathy. However, the presence of para-osteoarthropathies and negative HLA-B27 in paraplegics would help in differential diagnosis.     

强直性脊柱炎骶髂关节的CT诊断价值

目的探讨强直性脊柱炎（AS）患者骶髂关节病变的CT表现,并评价其对早期诊断的意义。方法对46例经临床证实AS患者骶髂天节病变的CT表现进行了回顾性分析,并参照修订的AS纽约标准（5级分类法）对全部患者的骶髂关节病变进行了分级。结果研究证实,本组46例均有异常CT表现。其中,Ⅱ级（早期,7例）CT表现为骶髂关节受累,关节面轻度硬化、毛糙,皮质白线消失,关节面细小囊变,但关节间隙仍正常;Ⅲ级（进展期,35例）CT表现为骶髂关节面呈虫蚀状侵蚀,软骨钙化,关节面骨质增生硬化,关节间隙略增宽或不均匀变窄;Ⅳ级（晚期,4例）CT表现为关节骨性强直,关节间隙消失。结论CT能清晰显示骶髂关节的微细结构及其病理改变,极有利于诊断AS患者早期骶髂关节病变。     

Subchondral insufficiency fracture of the femoral head in a patient with alkaptonuria

We report a patient with alkaptonuria accompanied by bilateral rapidly destructive arthrosis of the hip. The destruction of the left hip joint with its severe functional impairment necessitated total hip arthroplasty (THA). The outcome was satisfactory. Both magnetic resonance imaging (MRI) and pathologic findings were compatible with a subchondral insufficiency fracture. A year and half later, during a follow-up visit, the patient complained of right coxalgia. Radiography showed that the right femoral head had already disappeared, requiring THA of the right hip. Although there have been a few reports of rapid destructive hip osteoarthritis associated with ochronotic arthropathy, the pathogenesis of the destructive change is not clear. Subchondral insufficiency fracture was diagnosed on MR imaging and pathologically confirmed in our patient with alkaptonuria, suggesting that subchondral insufficiency fracture is one of the causes of ochronotic hip destruction.     

Arthroscopic treatment of shoulder ochronotic arthropathy: a case report and review of literature

Alcaptonuria is an inherited hereditary metabolic disorder, which is associated with various systemic abnormalities and related to the accumulation of homogentisic acid and a derived melanine-like pigment in the connective tissues; the latter is termed ochronosis. We present the arthroscopic findings in the shoulder of a 58-year-old female with ochronotic arthropathy and discuss the role of arthroscopy in the diagnosis and management of this rare metabolic disorder.     

Can imaging findings help differentiate spinal neuropathic arthropathy from disk space infection? Initial experience

PURPOSE: To determine if radiographic, computed tomographic (CT), and magnetic resonance (MR) imaging findings can help differentiate spinal neuropathic arthropathy from disk space infection. MATERIALS AND METHODS: Imaging studies in 33 patients were evaluated, including 14 patients with spinal neuropathic arthropathy (12 radiographic, seven CT, and six MR studies) and 19 with disk space infection (13 radiographic, nine CT, and 12 MR studies). Potential imaging discriminators, including endplate sclerosis or erosions, osteophytes, spondylolisthesis, facet involvement (narrowing or erosions), vacuum disk, paraspinal soft-tissue mass, joint disorganization, and osseous joint debris, were recorded, as were MR imaging signal intensity and gadolinium-enhancement characteristics. RESULTS: The most helpful findings for diagnosis of spinal neuropathic arthropathy were vacuum disk on radiographs and CT images, debris on radiographs and CT and MR images, disorganization on radiographs and CT and MR images, facet involvement on radiographs and CT and MR images, spondylolisthesis on CT and MR images, diffuse signal intensity patterns in vertebral bodies on MR images, and rim enhancement of disks on gadolinium-enhanced MR images. Findings that were not helpful included endplate sclerosis and erosions, osteophytes, paraspinal soft-tissue mass, and decreased disk height. CONCLUSION: Vacuum disk, facet involvement, vertebral body spondylolisthesis, joint disorganization and debris, and gadolinium-enhancement patterns of vertebral bodies and disks may help differentiate spinal neuropathic arthropathy from infection.     

Course of radiologic changes in spondyloarthropathy caused by dialysis

Destructive spondyloarthropathy (DSA) has been observed in patients undergoing long-term hemodialysis. The pathophysiology of this condition is still unknown, but there is evidence that amyloid depositions play an important role in its development. Despite several reports, the radiological evolution of these lesions is poorly known. The authors report the results of the radiographic follow-up (12-18 months) of 9 cases (7 female and 2 male patients; age 63 +/- 6 years) hemodialyzed for over 60 months (mean: 126 +/- 33). In 7 cases, radiographic patterns of destructive arthropathy were seen in peripheral joints as well. X-ray pictures demonstrated: 1) increased erosion of vertebral end plates (in all cases); 2) increased narrowing of intervertebral spaces (in 5 cases); 3) increased collapse of vertebral bodies (in 5 cases); 4) increased malalignment of the involved segments (in 4 cases). In 3 autopsied cases beta 2-microglobulin amyloid depositions were found in disc and ligamentous paravertebral tissue. These results confirm that: 1) DSA is progressive in long-term hemodialysis patients; 2) radiographic evolution is often very quick; 3) the cervical spine is the most frequently involved location and the one where lesions are quickest to develop; 4) severe malalignment of the involved spine may be present, with subsequent neurological complications.     

Association of diffuse idiopathic skeletal hyperostosis (DISH) and calcification and ossification of the posterior longitudinal ligament.

Diffuse idiopathic skeletal hyperostosis (DISH) is a common ossifying diathesis in middle-aged and elderly patients characterized by bone proliferation along the anterior aspect of the spine and at extraspinal sites of ligament and tendon attachment to bone. Four patients with DISH revealed extensive calcification and ossification of the posterior longitudinal ligament in the cervical spine. Review of cervical spine radiographs in 74 additional patients with DISH demonstrated bony hyperostosis of the posterior aspect of the vertebrae in 41%, posterior spinal osteophytosis in 34%, and posterior longitudinal ligament calcification and ossification in 50%. These ligamentous findings, which have previously been described almost exclusively in Japanese people, appear to be an additional skeletal manifestation of DISH.     

腰椎小关节综合征的CT诊断及与X线平片的对比

目的 评价CT对腰椎小关节综合症的诊断价值。方法 回顾分析24例腰椎小关节综合症的CT表现并与X线对比分析。结果 CT对腰椎小关节综合症的检出率明显高于X线，且对伴随椎间盘膨出、突出，侧隐窝和椎管挟窄，黄韧带肥厚和钙化，关节囊真空征等可一次性检出。结论 CT可充分显示椎小关节解剖结构和病理改变，为小关节综合征的诊断提供可靠的影像学根据。     

CT诊断腰椎小关节综合征的价值

目的分析腰椎小关节综合征的CT表现,探讨CT对该病的诊断价值.材料和方法回顾性分析59例腰椎小关节综合征的CT表现.结果腰椎小关节综合征小关节异常主要包括小关节增生肥大、骨赘形成、关节间隙变窄、小关节真空现象,小关节半脱位、关节囊钙化及两侧小关节不对称以及侧隐窝狭窄,椎间盘真空征及轻度腰椎退行性滑脱.结论CT扫描可对腰椎小关节综合征诊断提供可靠影像学依据,对改进临床诊断和治疗腰腿痛有重要意义.     

Lumbar platyspondyly — characteristic sign of Ehlers-Danlos syndrome

Three patients with Ehlers-Danlos syndrome have been observed to have isolated flattening of the lumbar vertebral bodies. Flattening of the lumbar vertebrae with normal appearance of the rest of the spine may be an important radiological clue to early recognition or confirmation of the diagnosis of Ehlers-Danlos syndrome.     

脊柱单椎体结核与单椎体转移瘤的 CT表现差异探讨

目的 探讨单椎体结核与单椎体转移瘤的CT表现差异.方法 回顾性分析和比较经临床或病理证实的16例单椎体结核与17例单椎体转移瘤的CT表现,拟订出进行鉴别诊断的CT表现差异指标.结果 单椎体结核多发生于椎体的前中部,病灶边缘可见硬化缘,其内可见死骨,椎旁肿块多为脓肿,其内常有钙化,多呈周边强化,累及范围广;单椎体转移瘤多发生于椎体中后部及附件骨,少有死骨及边缘硬化,椎旁肿块内少有钙化,强化明显;单椎体结核与转移瘤都罕有累及椎间盘.结论 根据上述CT表现差异,可较明确地做出二者的鉴别诊断;椎间盘破坏与否不能作为二者的鉴别点.     

Osteoarticular brucellosis: results of bone scintigraphy in 140 patients

One hundred forty patients with proved brucellosis and clinical evidence of bone and joint involvement were evaluated prospectively by 99mTc-methylene diphosphonate scintigraphy to assess the frequency of positive findings. To evaluate the radiographic abnormalities associated with positive scintigraphy, all areas of the skeleton that showed abnormal uptake were studied further by plain radiography. High-resolution CT was performed in all patients who had spinal lesions. Ninety-six patients (69%) had abnormal radionuclide uptake in 57 extraspinal and 101 spinal sites. Uptake was increased in 53 joints and three long bones and decreased in one joint. The knee was the most frequently involved site; the second was the sacroiliac joint. Radiographic and high-resolution CT changes were seen in only 12 (21%) of 57 extraspinal sites. In the spine, the abnormal scintigrams showed either focal increased uptake in affected vertebral bodies (detected mostly on the anterior view and seen in 51 lower thoracic and lumbar vertebrae in 24 patients) or diffuse increased uptake in adjacent vertebrae (detected in anterior and posterior views and seen in 50 different disk levels in 38 patients). Radiographic and high-resolution CT changes were seen at all scintigraphically positive sites. We conclude that bone scintigraphy is a useful method for screening patients with osteoarticular brucellosis. It is more sensitive than radiography in assessing involvement of the extraspinal skeleton and in the spine, it allows accurate localization of affected areas.