Imaging of inflammatory arthritis MODERATOR: PROF. SUNIL KUMAR PRESENTER: DR NABA KUMAR JR II
When joints are inflamed they can develop stiffness, warmth, swelling, redness and pain The word "arthritis" means joint inflammation, the term is used to describe various diseases and conditions that affect joints, the tissues that surround the joint, and other connective tissue.
Basic terminologies Monoarticular – single joint Pauciarticular - 2-4 joints Polyartricular - >4 joints Enthesis – bone-tendon jn , bone-ligament jn Enthesopathy – inflammation at lig or tendon insertion (enthesis) Hyperostosis – exuberant calcification of ligament or tendon Osteophyte – degenerative bony outgrowth continuous with underlying cortex Spondylophyte – spinal osteophyte
Inflammatory arthritis is characterized by bone erosions, osteopenia , soft tissue swelling and uniform joint space narrowing. Inflammation that involves multiple joints in proximal distribution of hand or feet without bone proliferation suggests rheumatoid arthritis. Inflammation that involves multiple joints in distal distribution of hand or feet with bone proliferation suggests a seronegative spondyloarthropathy . With monoarticular joint inflammation, it is important to exclude infection. INFLAMMATORY ARTHRITIS
Radiography is typically the first imaging study in evaluation for arthritis. . Imaging Modalities Still the most widely used investigation Skeletal survey – disease distribution Treatment monitoring Not sensitive for early disease On radiographs one critical assessment is differentiating inflammatory arthritis from a degenerative process, because the treatment options are quite different RADIOGRAPHY
Common Radiological Features of Arthritis Soft tissue swelling Subcho n d r al sclerosis and erosion Narrowing of joint space Joint effusion. Os t eo p h y t es formation Suchondral cystic lesion. P eriart i cular os t eo p o r osis
2-Ultrasound Joint effusion Synovial thickening& hypervascularity Erosions Monitor disease activity & progression Guided aspiration & injections 3-Computed Tomography Limited role Imaging of CV junction Better demonstration of new bone formation and bony ankylosis
4-Magnetic Resonance Imaging Gold standard for synovial imaging Detection of active synovitis Bone marrow changes Scoring Early detection of erosions ( MRI erosions progress to radiographical erosions with in 2 yrs ) 5-Radionuclide scanning Radiolabelled polyclonal human Ig Highly sensitive detection of inflammatory changes Poor specificity
Radiological Approach A lignment B one density C artilage/joint space D istribution E rosions S oft tissue changes
Bone Density Reduced bone density RA, Juvenile chronic arthritis Pyogenic (after 10 days) Tuberculous Reiter (Acute) Hemophilia Scleroderma Maintained bone density OA CPPD Gout Psoriasis AS Reiter chronic or recurrent Pigmented villonodular synovitis
3.Cartilage-Joint Space Types of changes Increase – overgrowth, effusion or interposition: Early arthritis Psoriatic Pigmented villonodular synovitis Gout Decrease – cartilage destruction Uniform (inflammatory arthritis) Non-Uniform (degeneration) . Ankylosis - Bony fibrous
Joint space narrowing: Inflammatory : Uniform joint space narrowing. Degenerative : Nonuniform Joint Space narrowing. Symmetrical VS Asymmetrical
Arthropathy Distribution in Small Joints Distal Proximal General Psoriasis RA Gout Reiter’s Syndrome CPPD Osteoarthritis Sarcoid Bilateral Symmetry Rheumatoid Arthritis Multicentric Reticulohistiocytosis
Erosions Distal - Psoriasis Erosive OA Reiter’s Proximal – RA CPPD Non – erosive - SLE Rheumatic fever (rare)
Bony erosionVS sclerosis & ostephytosis Bony erosion - Hallmark of joint inflammation. Sclerosis & osteophytosis – Hallmark of degenerative arthritis
Rheumatoid Arthritis:- Rheumatoid arthritis is a progressive, chronic, systemic inflammatory disease affecting primarily the synovial joints Onset is usually between 20 and 60 years of age, with the h ighest incidence among the 40- to 50-year-old group. Under 40 females to male ratio is 3:1 and over 40 equal, 1:1 ratio incidence. The detection of rheumatoid factor, representing specific antibodies in the patient's serum, is an important diagnostic finding
Low-grade fever, fatigue, weight loss, muscle soreness, and atrophy. Symmetric peripheral joint pain and swelling, particularly of the hands. Pathologic Features:- Initial synovial inflammation within joints, bursae, and tendon sheaths, with cellular infiltrate, hyperemia, edema,and increased synovial fluid. Synovium becomes hypertrophied to form granulation tissue (pannus), which spreads over cartilage surface. At the bare areas pannus directly invades into the bone, resulting in marginal erosions and cartilage destruction. A rheumatoid nodule is diagnostic and consists of three distinct zones: fibrinoid degeneration and necrosis (central), radial palisading of fibroblasts (middle), and fibrous tissue with small cell infiltrate (outer).
Radiologic Features Early radiographic changes are most commonly seen in the hands and feet. Bilateral and symmetric distribution, periarticular soft tissue swelling(these are typically the first radiographic signs of rheumatoid arthritis.), juxta-articular osteoporosis, juxta-articular solid or laminated periostitis, marginal erosions and cysts, and uniform loss of joint space. Later, radiographic changes may be seen, including marked deformities with subluxation, dislocation, articular bony destruction, bony fusion, and complete destruction of joint space.
Hand: earliest changes are seen at the metacarpophalangeal and PIP joints. Evaluation should include the semisupination view of the hands (Norgaard projection) for marginal erosions on metacarpal heads and deformities like ulnar deviation, boutonniere, swan neck, spindle digit. Wrist: earliest change is erosion of ulnar styloid, multiple carpal erosions (spotty carpal sign), most common location for bony ankylosis, carpal radial rotation, zigzag deformity, Terry Thomas’ sign. Feet: earliest changes seen at the fourth and fifth metatarsal phalangeal joints. Changes parallel and are identical to that seen in the hands; Lanois deformity—dorsal subluxation of the metatarsal-phalangeal joints, with fibular deviation.
Cervical spine: most commonly affected area of the spine; involved in up to 70% of rheumatoid patients. Increased atlantodental interspace > 3 mm (especially in flexion), odontoid erosions, subluxations (especially C3, C4, and C5). Narrowed intervertebral discs, apophyseal joints show erosions and narrowed joint space and may ankylose. Tapered spinous processes and generalized osteoporosis. Hips: uniform loss of joint space (axial migration), minimal erosions, protrusio acetabuli (most common cause),particularly bilaterally. Knees: uniform loss of joint space, marginal erosions (particularly at the tibial condyles), and osteoporosis; often associated with large Baker’s cysts.
Anteroposterior (A) and lateral (B) radiographs of the knee shows periarticular osteoporosis, joint effusion, and lack of osteophytosis.
Anteroposterior radiograph of the right hip shows erosions of the femoral head and acetabulum, concentric narrowing of the hip joint, and acetabular protrusio.
(A) Lateral radiograph of the foot of shows fluid in the retrocalcaneal bursa (arrow) associated with erosion of the calcaneus (curved arrow). MRI demonstrates bone erosion in the posterior process of the calcaneus ( arrowhead) associated with extensive surrounding bone marrow edema and retrocalcaneal and retro-Achilles bursitis (arrows).
Oblique radiograph of the hand shows the swan neck deformity of the second through fifth fingers
Radiograph of the hands demonstrates the boutonnière deformity in the small and ring fingers of the right hand and in the ring finger of the left hand
Figure : Rheumatoid arthritis. (a) Posteroanterior radiograph of right foot and (b) oblique radiograph of left foot show joint space narrowing and bone erosions of both metatarsophalangeal joints and several inter- phalangeal joints (arrows). Note most extensive involvement of fifth metatarsophalangeal and first interpha- langeal joints.
MRI A sagittal spin echo T1- weighted MR image shows inflammatory pannus eroding odontoid (arrow) and cranial settling with cephalad migration of C2 impinging on the medulla oblongata (open arrow).
Juvenile rheumatoid arthritis Chronic polyarthritis resembling rheumatoid arthritis clinically and histologically beginning before 16 years of age Synonyms include Still’s disease and juvenile chronic arthritis. More common in females < 16 years, with peak incidence at 2-5 and 9-12 years.
TYP E S Adult form (seropositive) ,Only 5-15% , Poorest prognosis Seronegative form:- Classic systemic ,Polyarticular Pauciarticular-monoarticular Distinct lack of rheumatoid factor Symptoms include fever, rash, lymphadenopathy, iridocyclitis (especially in monoarticularforms), no subcutaneous nodules, and growth disturbance. Distinct lack of rheumatoid arthritis Persistant arthritis in ≥ 1 jt for > 6wks in child < 16 yrs after excluding other causes
Radiologic Features General features include soft tissue swelling, osteoporosis, periostitis, growth disturbances, ankylosis, loss of joint space, erosions, subluxations, and epiphyseal compression fractures. Target sites include cervical spine, hands, feet, knees, and hips. Cervical spine: atlantoaxial dislocations, hypoplastic C2-C4 vertebral bodies and discs with ankylosed apophyseal joints. Tarsal and carpal ankylosis common. Growth deformities: brachydactyly, ballooned epiphyses, squashed carpi, and squared patellae.
Lateral Lumbar Note that osteoporosis and compression fractures have produced a biconcave appearance of the endplates. Lateral Cervical. Observe the vertebral body hypoplasia of the second, third, fourth, and fifth segments. The odontoid appears e nlarged C. Lateral Cervical. Note that the vertebral bodies are hypoplastic in combination with posterior joint ankylosis. These are characteristic cervical spine changes
Radiograph of both hands shows destructive changes in the metacarpophalangeal and interphalangeal joints. Note also joints ankylosis in both wrists. the periarticular soft tissue swelling and periostitis (arrows)
Radiograph of both knees of a 20- year-old woman shows overgrowth of the medial condyles, one of the characteristic features of this disorder
Ankylosing Spondylitis A chronic inflammatory disorder principally affecting the articulations, ligaments, and tendons of the spine and pelvis, often resulting in complete polyarticular ankylosis. Onset is usually between 15 and 35 years with male predilection. Initiates at the sacroiliac joints bilaterally, then ascends the spine.
Complications include iritis , aortitis , valvular incompetence, aneurysms, conduction blocks, upper lobe pulmonary fibrosis, inflammatory bowel disease, renal failure owing to secondary amyloidosis , carrot-stick fractures, Andersson’s lesion, and prosthesis ankylosis . The most commonly involved areas are the sacroiliac joints, spine, and proximal large joints of the shoulder, hip, and rib cage. Pain and tenderness, especially over bony protuberances, and increasing stiffness and sciatica is often bilateral or may alternate from side to side SI jt > thoracolumber > lumbosacral 15-35 yrs M:F ( 10: 1) ≈90% HLA B27
Pathologic Features In synovial joints, the initial change is that of a non- specific synovitis similar to rheumatoid arthritis, except that it is less extensive and of lower intensity (pannus formation), with subsequent fibroplasia , leading to resultant ossification. In cartilage joints, the initial subchondral osteitis is replaced by fibrous tissue that subsequently ossifies. In the outer annulus fibers this forms syndesmophytes. At entheses, inflammatory changes at ligamentous attachments result in bony erosions, sclerosis, and periostitis.
B/L symmetrical, Illiac side more involve Lower 2/3 of jt GRADES 1- Pseudo widening -hazy margin subchondral osteoporosis 2 & 3-Erosive & sclerotic change (MC stage seen) Rosary bead appearance 4- Ankylosis - Star sign Ghost joint margin Radiologic Features
SPINE : AS All joints Romanus sign –outer annulus enthesitis --- erosions Squaring -erosion+ periostitis Barrel shaped vertebra Shiny corner sign-reactive transient sclerosis Marginal syndesmophyte – bamboo/poker spine Trolley track appearance – apophyseal capsule,spinal ligament & ligamentum flavum Dagger appearance Atlanto axial instability( 2-15 %) & shiny dens sign Carrot stick fracture Lateral radiograph of the lumbar spine demonstrates squaring of the vertebral bodies secondary to small osseous erosions at the corners. This finding is an early radiographic feature of ankylosing spondylitis. Note also the formation of syndesmophytes at the L4- 5 disk space.
A lateral radiograph of the lower lumbar spine of shows early inflammatory changes manifesting by so-called shiny corners (Romanus lesion) (arrowheads) and squaring of the vertebral bodies (arrows). T2-weighted MRI in a 26-year-old man shows early signs of ankylosing spondylitis of the lumbar spine, the shiny corners (arrows). T2-weighted MRI of the sacroiliac joints in the same patient demonstrates bone marrow edema adjacent to the sacroiliac joints and erosive changes bilaterally, more prominent on the left (arrows).
D
Psoriatic Arthritis Psoriasis is a common skin disorder associated with joint disease and characterized by peripheral joint destruction and deformity Age 20-50 years with male and female equally affected. Arthritis is usually in peripheral joints, especially DIP joints. Soft tissue findings: fusiform soft tissue swelling around the joints which can progress so that whole digit is swollen (sausage digit or dactylitis) Marginal erosions also often show fluffy periostitis from new bone formation Skin disorder with arthropathy ≈10-15% (Nail changes) HLA B27-≈75% Skin lesions precede arthritis – 70% Arthritis precedes skin lesions – 15% SI jt 35 – 50% Spine- 30 – 40%
Radiologic Features General features include soft tissue swelling, normal bone mineralization, erosions, and tapered bone ends, prominent juxta- articular fluffy periostitis, and joint-space widening or bony ankylosis. Hands and feet: asymmetric involvement and ray pattern, most commonly involves DIP joints, no osteoporosis, mouse ears sign, widened joint space owing to fibrous tissue deposition and bone resorption, pencil-in-cup deformity, opera glass hand deformity, no ulnar deviation.
Sacroiliac joint: involved in up to 50% of psoriatic arthritis patients, usually bilateral but asymmetric and unusual to be narrowed and ankylosed. Spine: atlantoaxial subluxation and dislocation, normal apophyseal joints (except in the cervical spine), syndesmophytes of two types— non—marginal, marginal (non-marginal are the most common)— broad-based and tapered, asymmetric, unilateral, and most common in the upper lumbar and lower thoracic spine.
RAY PATTERN PA Hand. Note the erosive changes are present at the three joints of the second digit (arrows). This pattern of arthritis is virtually diagnostic of psoriasis
Pencil and cup deformity Pencilling
Early Distal Interphalangeal Joint Changes. Note that erosions (arrows), periostitis (arrowheads), and soft tissue swelling characterize the earliest abnormalities Combination of erosions and fluffy periostitis produces the mouse ears appearance in psoriasis. MOUSE EAR SIGN
Non- Marginal Syndesmophyte. Note the thick, vertical ossifications that arise just beyond the vertebral body margins (arrows).
PA Hand. Fluffy and Linear. Note that close to the joint near the site of articular erosion, the periosteal new bone is typically fluffy ( arrowheads). Farther down the S haft a linear pattern may be seen (arrow). Great Toe: Fluffy. Note that adjacent to the erosions a fluffy and irregular type of periostitis can be seen ( arrowheads). The entire distal phalanx is sclerotic, a reliable sign of P soriatic arthritis involving the great toe.
Figure : Psoriatic arthritis. (a) Anteroposterior sacrum radiograph shows bone erosions and narrowing of sacroiliac joints with partial fusion (arrows). (b) Antero- posterior lumbar spine radiograph shows comma-shaped paravertebral ossifications (arrows).
Note severe joint destruction, especially at the metatarsophalangeal articulations, has resulted in fibular deviation and dorsal dislocation of the digits (Lanois’ deformity). The presence of a pencil- in-cup deformity (arrow) at the interphalangeal joint of the big toe and osseous ankylosis of the first metatarsophalangeal and second and third proximal interphalangeal articulations (arrowheads) makes the diagnosis of psoriatic arthritis most likely ARTHRITIS MUTILA N S
DIFFERENTIAL DIAGNOSIS Rheumatoid arthritis there is a MCP joint predominance in rheumatoid arthritis (RA) vs interphalangeal predominant distribution in PsA bone proliferation not a feature in RA osteoporosis not a feature in PsA Erosive osteoarthritis gull wing” central erosions are present in erosive OA vs “mouse ears” peripheral bare area erosions in PsA reactive arthritis (Reiter syndrome) “tends to involve feet > hands
REITER’S SYNDROME A triad of urethritis, conjunctivitis, and polyarthritis, usually following sexual exposure or, less commonly, certain types of dysentery. It typically occurs between the ages of 18 and 40, and is as much as 50 times more prevalent in males Joint symptoms typically consist of an asymmetric painful effusion, especially of the lower extremity Pain at the plantar or Achilles calcaneal attachment (lover’s heels) in a young male patient should suggest the diagnosis. These joint symptoms are of short duration and self-limiting within 2-3 months, but recurrences are common. Sterile inflammatory arthritis
Radiologic Features Swelling, osteoporosis, uniform loss of joint space, erosions, periostitis. Specific target sites: forefoot, calcaneum, ankle, knee, sacroiliac, spine. Foot: metatarsophalangeal and interphalangeal joints. Dorsal subluxation of the proximal phalanges and fibular deviation of the digits results in the Lanois deformity. Calcaneum: plantar and Achilles insertions. Ankle: loss of joint space, swelling, periostitis. Sacroiliac: erosions, sclerosis, loss of joint margin, asymmetric involvement and often unilateral. Spine: thoracolumbar, asymmetric, skip non-marginal syndesmophytes and, rarely, atlantoaxial instability Knee: the only change usually visible at the knee is effusion and, occasionally, periostitis of the distal femoral metaphysis. A Pellegrini- Stieda type calcification of the medial collateral ligament may be seen
Xray foot shows the thin layer of periosteal new bone at the phalangeal base at the third metatarsophalangeal joint (arrows). There is also a notable diminished density in the metatarsal head (arrowhead).
Xray Finger show marginal erosions (arrows), linear periostitis (arrowheads), and soft tissue swelling (crossed arrows) at the proximal interphalangeal joint.
CALCANEUS. A. Early Erosive Changes: Achilles Tendon. Shows small lucent defects (arrows) and adjacent periostitis (arrowhead). Pathophysiology. The inflamed pre-Achilles bursa (arrowheads) becomes the site for pannus formation and subsequent subperiosteal resorption of the adjacent calcaneus (arrow). Advanced Erosive Changes. Note that the lucent defects are larger (arrows), with prominent periostitis (arrowheads). Note the fluffy calcaneal spur owing to inflammatory enthesopathy (crossed arrow).
MEDIAL COLLATERAL LIGAMENT CA L CI FIC A TI O N . Note the irregular linear density adjacent to the medial epicondyle (arrow). This is a Pellegrini-Stieda type of calcification within the medial collateral ligament and may be seen in approximately 10% of Reiter’s syndrome patients
AP radiograph of the lumbar spine with reactive arthritis demonstrates a paraspinal ossification bridging the L2 and L3 vertebrae.
Enteropathic arthropathy Causes -UC > Crohn’s (common) Whipple’s Salmonella,Shigella , Yersinia Post bypass Collagenous colitis Radiographic findings identical to AS except Isolated SI jt mc 10-12% HLA B27 HOA CAN BE SEEN
Systemic lupuserythematorsis (SLE) Erosion characteristically absent Finding : hand >>spine B/L symmetrical reversible deformities, Plain xray – May be normal Spontaneous fractures Hands Bilateral symmetry Ulnar deviation (reversible) Boutonniere and swan-neck deformities (reversible) Osteoporosis Normal joint space Soft tissue atrophy Chest Pleural effusions and thickening Cardiomegaly Long bones Osteonecrosis (hips, shoulders, knees, hands, feet) Osteoporosis Spontaneous fractures Atlantoaxial instability Calcinosis universalis, cutis Tendon rupture Tuft resorption Uncommon
A. PA Hands. Note the complete dislocation of the metacarpophalangeal joints, swan-neck deformities of the fingers, and boutonniere configuration of the thumbs bilaterally. B. Hands. Same patient with hands placed firmly on the cassette. Note the reversibility of all deformities.
CALCINOSIS CIRCUMSCRIPTA . A. AP Knee. Observe the soft tissue calcifications ( arrows ). B. AP Shoulder. Note the generalized osteoporosis and fracture of the humerus ( arrow ). C. Abdomen. Note the diffuse soft tissue calcification ( arrow ). A hip prosthesis has been performed for corticosteroid-induced osteonecrosis ( arrowhead ).
1-Pulp atrophy associated + calcinosis cutis/ circum scripta 2-Acro-osteolysis + calcinosis is virtually diagnostic 3-Joints-Normal, SCLERODERMA DIGITAL PATTERNS OF CALCINOSIS CUTIS . A. Punctate. B. Sheet-Like. Manifestations of rheumatoid arthritis, erosive osteoarthritis, or psoriasis Erosive arthropathy at first metacarpal-carpal joint SCLERODERMA WITH DIGITAL SKIN RETRACTION AND EARLY ACROOSTEOLYSIS.