Plain X-ray Images

24 Plain X-Ray Images Chi-Ho Lee and Chak-Sing Lau Case 24.1 Leading question A 45-year-old man presents with abdominal pain and frequent bumping into corners at home.

Case 24.1 Plain X-Ray Images 377 Questions 1 — o Name one abnormality on the skull X-ray. . What further imaging could confirm the abnormality? . What causes the abdominal pain? . Explain the problem of frequent bumping into corners. . What is the clinical syndrome? Answers W - v Double flooring of pituitary fossa. Magnetic resonance imaging (MRI) of the pituitary. Renal colic. Visual field defect. Multiple endocrine neoplasia Type 1. Description Expansion of the sella turcica. Enlarged frontal sinus. Thickened skull vault. Prognathous jaw. There is ballooning of the pituitary fossa, erosion and destruc- tion of the anterior, posterior clinoids, and of the tuberculum sellae. Enlargement of paranasal sinuses and widening of the mandibular angle with prognathism. Discussion Space-occupying lesions of the pituitary gland produce distur- bances in two aspects: structural and functional. Structural: space-occupying lesion of the pituitary fossa if larger than 1 cm can compress on the optic chiasm, producing bitemporal hemianopia.

378 Problem-Based Medical Case Management Case 24.1 e In this patient with acromegaly, the pituitary fossa is greatly enlarged due to the directly expanding effect of an adenoma of the anterior pituitary gland. A “double flooring” of the sella occurs when the tumour expands downwards unevenly. His MRI pituitary shows a pituitary macroadenoma. Coronal image Saggital image « Functional: hormonal disturbances originating from the pitui- tary gland involve either hyper- or hypo-secretion of hormones. « Deficiency of ACTH, TSH or antidiuretic hormone, alone or in combination may lead to life-threatening situations. * Hormonal hypersecretion is usually due to hormone-secreting pituitary tumours, notably growth hormone-secreting (acro- megaly), prolactinoma, and ACTH-secreting (Cushing’s disease) tumours. Acidophilic or chromophobe adenomas of the pituitary are occasionally associated with functioning islet cell tumours of the pancreas, and adenomas of the parathyroids giving rise to the disorder, called multiple endocrine neoplasia Type 1. The disorder is frequently familial and may present with symptoms of the pituitary tumour, hypoglycaemia, hypercalcaemia or gas- trointestinal bleeding. ¢ Renal colic is due to renal stones secondary to hypercalcaemia.

Case 24.2 Plain X-Ray Images 379 Case 24.2 Leading question A 65-year-old woman presented to her general practitioner with acute back pain located at the upper lumbar region. X-rays of the lumbar spine were taken. Ibuprofen 400 mg t.i.d. was prescribed, but there was only partial improvement in the patient’s back pain. Questions 1. Describe four radiological abnormalities. 2. Name two radiological diagnoses. 3. What is the likely cause of this patient’s acute back pain? 4. What other treatment would you offer this patient?

380 Problem-Based Medical Case Management Case 24.2 Answers 1. Y Loss of joint space between L5 vertebral body and the sacrum; osteophytosis; osteopenia; partial compression fracture of T12 and L5 vertebral bodies. . Lumbar spondylosis; osteoporotic fracture of T11 to L1 verte- bral bodies. . Osteoporotic fracture. . Bisphosphonates, monoclonal antibody against receptor acti- vator of nuclear factor kappa-B ligand (RANKL) (e.g., deno- sumab), strontium, oral selective oestrogen receptor modulator (SERM) (e.g., raloxifene), and recombinant human parathyroid hormone (e.g., teriparatide). Description and discussion Both the anteroposterior and lateral views of the lumbar spine show loss of cartilage space between the L5 vertebral body and the sacrum. Anterior osteophyte (bony overgrowth) is seen at the upper border of the L5 vertebral body. Marked osteophytes are also seen at the upper and lower borders of the other ver- tebral bodies. These changes are due to degeneration (osteoar- thritis) of the lumbar spine. Besides, the density of the vertebral bodies appears diminished and the T11 and L1 vertebral bodies are partially collapsed. Lumbar spondylosis (osteoarthritis of the lumbar spine) typi- cally produces chronic progressive back pain which is worse after exertion, although some patients may remain asymp- tomatic. In general, correlation between the severity of pain and that of radiological changes of osteoarthritis is poor. Most cases of lower back pain are due to simple mechanical strain which usually responds to the use of simple analgesics and non- steroidal anti-inflammatory drugs. With the above radiological findings, the patient’s presentation of acute pain in the upper lumbar spine region and a lack of response to a simple non- steroidal anti-inflammatory drug, the most likely diagnosis is recent compression fracture secondary to osteoporosis. Some

Case 24.3 Plain X-Ray Images 381 patients may present after a fall but such history may not always be apparent. With 3 of the vertebral bodies being collapsed, it is possible that this patient had had repeated compression fractures. Case 24.3 Leading question A 30-year-old housewife had been suffering from on-and-off lower back pain for 6 months. There was no history of trauma, but the pain was worse after playing with her 2-year-old son. X-rays of the lumbar spine (below left) and pelvis (below right) were taken. In view of the X-ray appearance and the patient’s relative young age, her family physician requested HLA B27 tissue typing. It was reported to be positive.

382 Problem-Based Medical Case Management Case 24.3 Questions 1. Describe the most prominent radiological abnormality. 2. What is the radiological diagnosis? 3. What is the underlying diagnosis of this patient’s lower back pain? Answers 1. Periarticular osteosclerosis of both sacroiliac joints. 2. Osteitis condensa. 3. Simple mechanical back pain. Description and discussion ° The anteroposterior view of this patient’s lumbar spine X-ray appears normal. However, X-ray of the pelvis shows periarticu- lar osteosclerosis of both sacroiliac joints. An oblique view of the two sacroiliac joints (below left and right) shows the scle- rotic changes are confined to the iliac side. This is typical of osteitis condensa, a radiological diagnosis which is found in previously pregnant women.

Case 24.3 Plain X-Ray Images 383 ° The underlying pathology of osteitis condensa is poorly under- stood, but it is often an incidental radiological finding with poor correlation with the patient’s symptoms. ¢ Although this patient is young and she is HLA B27 positive, her history of on-and-off back pain which was worse after playing with her child and the lack of radiological changes exclude the diagnosis of ankylosing spondylitis. The low specificity of HLA B27 in diagnosing ankylosing spondylitis and related syn- dromes has been highlighted previously. Radiologically, sacro- iliitis is characterized by periarticular osteosclerosis on both sides of the sacroiliac joint, joint space-widening because of inflammation induced oedema, and an irregular margin due to erosion of the joint. In advanced cases, the sacroiliac joint may become fused (below left). Radiological changes of the spine of a patient with ankylosing spondylitis may include squaring of the vertebral bodies, calcification of the intervertebral discs, syndesmophyte formation, and in advanced cases, bamboo appearance of the whole spine (below right). If in doubt, MRI of the sacroiliac joints and lumbar spine may help to differenti- ate the diagnosis of spondyloarthritis.

384 Problem-Based Medical Case Management Case 24.4 Case 24.4 Leading question A 55-year-old woman had been complaining of pain and swelling of multiple joints for 10 years. She had always consulted her local family physician, who prescribed her with simple analgesics and non-steroidal anti-inflammatory drugs. The response had always been suboptimal, but the patient refused referral to a specialist. Recently, her arthritis had become unbearable. She was admitted to a local hospital for further management. X-rays of the hands and feet were taken.

Case 24.4 Plain X-Ray Images 385 Questions 1. 2. 3. Describe three radiological abnormalities. Name two differential diagnoses. What other physical signs would you look for? Answers I. [SSNS) On the hand X-rays, there is periarticular osteopenia; loss of joint space and periarticular bony erosions involving multiple joints including the wrist, metacarpophalangeal, and proximal interphalangeal joints. Corresponding changes are seen on X-rays of the feet. . Psoriatic arthritis; rheumatoid arthritis. . Por psoriatic arthritis: dystrophic nail lesions such as pitting and hyperkeratosis and scaly erythematosus skin lesions which are commonly found on the scalp, extensor surfaces of both upper and lower limbs, anterior surface of both shins, lower back and peri-umbilical region. For rheumatoid arthritis: subcutaneous nodules on the ulnar border of elbows and forearms and other pressure sites; and other extra-articular manifestations such as digital vasculitis and pulmonary fibrosis. Description and discussion Radiological changes of theumatoid arthritis and psoriatic arthri- tis may be indistinguishable although bony resorption is more commonly seen in the latter condition. Additionally, psoriatic arthritis may sometimes affect the distal interphalangeal joints, which is uncommon in rheumatoid arthritis.

386 Problem-Based Medical Case Management Case 24.5 Case 24.5 Leading question A 65-year-old man consulted his general practitioner because he had noticed progressive finger joint swelling. Other than occa- sional niggling pain which usually responded to simple analgesics, the patient was not troubled by his joint condition. X-rays of the hands were taken. Questions 1. Describe four radiological abnormalities. 2. What is the diagnosis? 3. Does this patient require regular arthritis treatment?

Case 24.6 Plain X-Ray Images 387 Answers 1. There is loss of joint space, periarticular osteosclerosis, osteo- phyte formation, and subchondral cyst formation involving multiple joints including both first carpometacarpal and inter- phalangeal joints, and the proximal and distal interphalangeal joints. . Osteoarthritis. No. Description and discussion This patient’s X-rays exhibit typical changes of osteoarthritis with loss of joint space, periarticular osteosclerosis, and osteo- phyte formation. The hand joints that are particularly affected by osteoarthritis include the first carpometacarpal joint, first interphalangeal joint, distal interphalangeal joints and, less commonly, proximal interphalangeal joints. Note that, in con- trast to rheumatoid arthritis, this patient’s metacarpophalangeal and wrist joints are spared. As with osteoarthritis of the other joints, correlation between radiological changes and the severity of symptoms is poor. Since this patient is relatively symptom free, there is no need for any regular medication. Case 24.6 Leading question A 45-year-old woman with known rheumatoid arthritis for 10 years complained of progressive numbness and weakness of all 4 limbs. A cervical spine X-ray was taken.

388 Problem-Based Medical Case Management Case 24.6 Questions 1. What view is this cervical spine X-ray? 2. Describe three radiological abnormalities. 3. What other radiological investigation would you recommend?

Case 24.6 Plain X-Ray Images 389 Answers 1. Lateral flexion view. 2. Generalized osteopenia; erosion of the odontoid process axis and the anterior arch of the first cervical vertebral body (atlas) and atlantoaxial subluxation. Magnetic resonance imaging of the cervical spine to look for impingement of the spinal cord by the odontoid process. Description and discussion The clinical differential diagnoses here include cervical myelopathy and mononeuritis multiplex, both of which are complications of rheumatoid arthritis. The former is caused by subluxation of the atlantoaxial joint (C1/2 subluxation) result- ing in displacement of the odontoid process either upperwardly or posteriorly compressing on the cervical cord. Mononeuritis multiplex may be secondary to a vasculitic neuropathy which is an uncommon complication of rheumatoid arthritis. Patients may also manifest other extra-articular disease such as rheu- matoid nodules, vasculitic skin rashes, digital vasculitis, and pulmonary fibrosis. To look for possible C1/2 subluxation on a plain X-ray, it is essential to ask for a lateral flexion view of the cervical spine although forced flexion should be avoided. A lateral extension view may not demonstrate the odontoid process displacement. On this X-ray, there is advanced rheumatoid arthritis involve- ment of the atlantoaxial joint. The articular surface of the ante- rior arch of C1 (atlas) appears irregular due to erosions. The odontoid process of C2 (axis) is poorly visible and is likely to have been eroded by the rheumatoid process. The axis is dis- placed posteriorly and may be compressing on the spinal cord. The odontoid process of the axis may also be displaced upwardly. Radiologically, this is determined by drawing a line between the posterior edge of the hard palate and the posterior edge of the foramen magnum—the chamberlain line. The tip of the odontoid process should normally be not more than 2.5 mm above this line.

390 Problem-Based Medical Case Management Case 24.6 * Plain X-ray appearance of C1/2 subluxation does not confirm the diagnosis of cervical myelopathy. This should be evaluated using magnetic resonance imaging, which is capable of visual- izing the spinal cord and whether there is compression by the odontoid process.