PowerPoint Presentation

ARTHRITIS

Dr. SHOPNIL PRASLAJr-1 ,DEPARTMENT OF RADIOLOGYMVP DR VASANTRAO PAWAR MEDICAL COLLEGE

TYPES OF ARTHRITISDEGENERATIVE ARTHRITISPrimary Osteoarthritis:-Idiopathic(spontaneous) no specific cause known but tend to be associated with agingSecondary osteoarthritis:-caused by previous injury to affected bone,can began at young age.

INFLAMMATORY ARTHRITISRheumatoid arthritis:- autoimmune diseases involves chronic inflammation of synovium within joint(involves multiple joint on both side)Psoriatic arthritis:-autoimmune diseases which associated with psoriasis.Ankylosing spondylitisReiter syndrome Erosive osteoarthritis.

METABOLIC ATHRITIS:-

Gout :- Caused by deposition of monosodium urate monohydrate crystal

Calcium Pyrophosphate Dihydrate Crystal Deposition Disease (Pseudogout) :-caused by deposition of calcium pyrophosphate crystal

INFECTIOUS ARTHRITISSeptic arthritis:-Life and limb threatening bacterial infection of the joint.

CONNECTIVE TISSUE ARTHRITIS:-Systemic lupus erythematous

Target sites of various arthritis in a joint.

Common Radiological Features of ArthritisSoft tissue swellingSubchondral sclerosis and erosionNarrowing of joint spaceJoint effusion.Osteophytes formationSuchondral cystic lesion.Periarticular osteoporosis

DEGNERATIVE ARTHRITISOSTEOARTHRITISNon-inflammatory degeneration of joint cartilage with secondary effects on adjacent bone.It is degenerative condition affecting articulation especially those which bear weight or subjected to much wear and tearIt affects individuals aged 50 years and older and much more common in women than men.Generally, in osteoarthritis, the large diarthrodial joints such as the hip or knee and the small joints such as the interphalangeal joints of the hand are most often affected; the spine, however, is just as frequently involved in the degenerative processIt begins focally and gradually increases in size.Initial loss of chondroitin sulfate leads to fibrillation and flaking, with secondary stress effects on adjacent bone.Escape of synovial fluid into subchondral bone forms subchondral bone cysts

Osteoarthritis of the Large JointsThe hip and knee joints are the most common sites of osteoarthritisThere radiographic features of degenerative joint disease in the hip:-Narrowing of the joint space as a result of thinning of the articular cartilage.Subchondral sclerosis (eburnation) caused by reparative processes (remodeling)Osteophyte formation (osteophytosis) as a result of reparative processes in sites not subjected to stress (so-called low-stress areas), which are usually marginal (peripheral) in distribution

Cyst or pseudocyst formation resulting from bone contusions that lead to microfractures and intrusion of synovial fluid into the altered spongy bone in the acetabulum, these subchondral cyst-like lesions are referred to as Eggers cysts

AP radiograph of the hip demonstrates the radiographic hallmarks of osteoarthritis: narrowing of the joint space, particularly at the weight-bearing segment (arrow); formation of marginal osteophytes (open arrows); and subchondral sclerosis posterior

CT of osteoarthritis of the hip shows diminution of the joint space, osteophytes, and subchondral cysts in the femoral head.

Anteroposterior (A) and lateral (B) radiographs of the kneeDemonstrate narrowing of the medial femorotibial and femoropatellar compartments, subchondral sclerosis, and osteophytosis, which are typical features of osteoarthritis. Note that osteophytes that were not obvious on the frontal projection are much better demonstrated on the lateral radiograph.

MRI of osteoarthritis. (A) Sagittal proton density-weighted MRI of a shows involvement of the femoropatellar compartment. Note joint space narrowing, subchondral cyst (arrow), and osteophytes (open arrows)

(B) Coronal T2-weighted fat-suppressedMR image shows complete destruction of articular cartilage of the lateral joint compartment (arrows),subchondral edema (open arrows), and degenerative tear of the lateral meniscus (curved arrow).

COMPLICATION OF OSTEOARTHRITISAnteroposterior (A) and lateral (B) radiographs of the knee demonstrate predominantinvolvement of the medial femorotibial and femoropatellar joint compartments, with formation of two largeosteochondral bodies.

Osteochondral bodies.

MRI of osteochondral body. A low-signal intensity osteocartilaginous loose body in the anterior joint space is revealed on T1-weighted sagittal image (A) and T2-weighted (B) sagittal MR images of the knee (arrows).

Osteoarthritis of the Small JointsPrimary Osteoarthritis of the HandThe most commonly affected small joints those of the hand, particularly the proximal and distal interphalangeal and the first carpometacarpal articulations In the distal interphalangeal joints, if hypertrophic phenomena supervene and osteophytes are prominent, degenerative changes are accompanied by Heberden nodes.Similar deformities in the proximal interphalangeal joints are called Bouchard nodes .If the degenerative changes involve the first carpometacarpal joint, they may result in an odd deformation of the thumb.

Xray shows degenerative changes in the distal interphalangeal joints, manifested by Heberden nodes, and in the proximal interphalangeal joints, manifested by Bouchard nodes. Note also degenerative changes in the first carpometacarpal joint (arrow).

Radiograph of both hands in addition to the typical Heberden and Bouchard nodes shows deformative changes at the first carpometacarpal articulations, resulting in an odd configuration of both thumbs.

Secondary Osteoarthritis of the Hand:-

The most characteristic secondary osteoarthritic changes in the small joints may be observed in acromegalic and heamochromatic patients.These include soft-tissue prominence and enlargement of the terminal tufts and the bases of the terminal phalanges; there may also be widening of some articular spaces and narrowing of others.beak-like osteophytes at the heads of the metacarpals are a prominent feature

Radiograph of both hands of a shows widening of some and narrowing of other joint spaces, enlargement of the distal tufts and the bases of terminal phalanges, and beak-like osteophytes affecting particularly the heads of the metacarpals

Degenerative Diseases of the SpineDegenerative changes may involve the spine at the following sites:The synovial jointsatlantoaxial, apophyseal, costovertebral, and sacroiliacleading to osteoarthritis of these structuresThe intervertebral disks, leading to the condition known as degenerative disk diseaseThe vertebral bodies and annulus fibrosus, leading to the condition known as spondylosis deformansThe fibrous articulations, ligaments, or sites of ligament attachment to the bone leading to the condition known as diffuse idiopathic skeletal hyperostosis (DISH).

Osteoarthritis of the facet joints. Oblique radiograph of the lumbar spine demonstrates advanced osteoarthritis of the facet joints. Narrowing of the joint spaces, eburnation of the articular margins, and small osteophytes (arrows) are similar to the changes seen in osteoarthritis of the large synovial joints.

Degenerative changes of the vertebral facet joints are very common, particularly in the mid and lower cervical and the lower lumbar segmentsInvolvement of the apophyseal joints may exhibit a vacuum phenomenon which in fact represents gas in the joint. This finding is almost pathognomonic for a degenerative process.

Osteoarthritis of the apophyseal joints. (A) Oblique radiograph of the lumbosacral spine demonstrates a vacuum phenomenon of the facet joint L5-S1 (arrow) and eburnation of the subarticular bone (arrowheads)CT section through both facets clearly demonstrates the presence of gas

INFLAMMATORY ARTHRITISRheumatoid Arthritis:-Rheumatoid arthritis is a progressive, chronic, systemic inflammatory disease affecting primarily the synovial jointsOnset is usually between 20 and 60 years of age, with the highest 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 FeaturesEarly 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 deformitydorsal 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 Bakers cysts.

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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 thecalcaneus (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).

Xray demonstrates erosions in the radiocarpal and intercarpal articulations as well as the carpometacarpal joint, bilaterally (open arrows). Note, in addition, subtle erosions of the head of the first, third, fourth, and fifth metacarpals of the left hand and of the head of the second metacarpal of the right hand (arrows). A small erosion at the base of the middle phalanx of the ring finger of the left hand (arrowheads) andthe erosion in the right triquetropisiform joint (curved arrow) are also well seen.

Oblique radiograph of the hand shows the swan neck deformity of the second through fifth fingers

Radiograph of the hands demonstratesthe boutonnire deformity in the small and ring fingers of the right hand and in the ring finger of the left hand

Radiograph of the hands demonstrates the main-en-lorgnette deformity- the telescoping the fingers secondary to destructive joint changes and dislocations in the metacarpophalangeal joints

Radiograph of the cervical spine

MRIA sagittal spin echo T1-weighted MR image showsinflammatory pannus eroding odontoid (arrow) and cranial settling with cephalad migration of C2 impinging onthe medulla oblongata (open arrow).

USG Sonography shows thickened synovial tissue (arrows).

MRIMR images of the left shoulder of a show large articular and periarticular erosions, joint space narrowing, joint effusion, and a tear of the supra-spinatus tendon (arrows)Coronal T1-weighted MRI of the right knee in demonstratesa joint effusion with inflammatory pannus (arrow).

Juvenile rheumatoid arthritis

Chronic polyarthritis resembling rheumatoid arthritis clinically and histologically beginning before 16 years of ageSynonyms include Stills disease and juvenile chronic arthritis.More common in females < 16 years, with peak incidence at 2-5 and 9-12 years.

TYPESAdult form (seropositive) Poorest prognosisSeronegative form:- Classic systemic ,Polyarticular Pauciarticular-monoarticularDistinct lack of rheumatoid factorSymptoms include fever, characteristic rash, lymphadenopathy, iridocyclitis (especially in monoarticularforms), no subcutaneous nodules, and growth disturbance.Distinct lack of rheumatoid arthritis

Radiologic FeaturesGeneral 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.

A. Lateral LumbarNote that osteoporosis and compression fractures have produced a biconcave appearance of the endplates. B. Lateral Cervical. Observe the vertebral body hypoplasia of the second, third,fourth, and fifth segments. The odontoid appears enlarged. 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 SpondylitisA chronic inflammatory disorder principally affecting the articulations, ligaments, and tendons of the spine and pelvis, often resulting in complete polyarticular ankylosis.Synonyms include Marie-Strumpell disease, rhizomelic spondylitis, pelvospondylitis ossificans, and rheumatoid spondylitis.Onset is usually between 15 and 35 years and involves males 10:1.Initiates at the sacroiliac joints bilaterally, then ascends the spine.Pain and tenderness, especially over bony protuberances, and increasing stiffness and sciatica is often bilateral or may alternate from side to side.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, Anderssons 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.

Pathologic FeaturesIn 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 and cartilaginousetaplasia, 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.

Radiologic Features

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 cervical spine in a shows anterior syndesmophytes bridging the vertebral bodies and posterior f usion of the apophyseal joints, together with paravertebral ossifications, producing a bamboo-spineappearance. (B) radiograph the fusion of the sacroiliac joints and the involvement of both hip joints, which show axial migration of the femoral heads(D)MRI shows anterior syndesmophytes, calcification ofthe posterior longitudinal ligament, and preservation of the intervertebral disks.

(A) 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). (B) T2-weighted MRI in a 26-year-old man showsearly signs of ankylosing spondylitis of the lumbar spine, the shiny corners (arrows). (C) 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).

A. AP Sacrum. Note that bilateral sacroiliitis is clearly seen with erosions, hazy joint margin, and subchondral iliac sclerosis (arrows). B. Axial CT: Sacroiliac Joints. Observe the erosive iliac lesions (arrows) and the subchondral sclerosis arrowheads).

Psoriatic ArthritisPsoriasis 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

Radiologic FeaturesGeneral 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 typesnonmarginal, marginal (non-marginal are the most common)broad-based and tapered, asymmetric, unilateral, and most common in the upper lumbar and lower thoracic spine.

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

RAY PATTERN

Pencil and cup deformity

Pencilling

Early Distal Interphalangeal Joint Changes. Note that erosions (arrows), periostitis (arrowheads), and soft tissue swelling characterize the earliest abnormalitiesCombination 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).

Oblique radiograph of the lumbar spine in a shows a characteristic single coarse syndesmophyte bridging the bodies of L3 andL4. The right sacroiliac joint is also affected.

(B) AP radiograph of the lumbar spine with psoriasis reveals paraspinal ossification at the level of L2-3.

A. 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 theshaft a linear pattern may be seen (arrow). B. 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 ofpsoriatic arthritis involving the great toe.

Note severe joint destruction, especially at the metatarsophalangeal articulations, has resulted in fibular deviation and dorsal dislocation of thedigits (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 MUTILANS

DIFFERENTIAL DIAGNOSISRheumatoid arthritisthere is a MCP joint predominance in rheumatoid arthritis (RA) vs interphalangeal predominant distribution in PsAbone proliferation not a feature in RAosteoporosis 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

REITERS SYNDROMEA 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 malesJoint symptoms typically consist of an asymmetric painful effusion, especially of the lower extremityPain at the plantar or Achilles calcaneal attachment (lovers 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.

Radiologic FeaturesSwelling, 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 instabilityKnee: 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 inthe 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). B. Pathophysiology. The inflamed pre-Achilles bursa (arrowheads) becomes the site for pannus formation and subsequent subperiosteal resorption of the adjacentcalcaneus (arrow). C. Advanced Erosive Changes. Note that the lucent defects are larger (arrows), with prominent periostitis (arrowheads). Note the fluffy calcaneal spur owing to inflammatory enthesopathy (crossedarrow).

MEDIAL COLLATERAL LIGAMENT CALCIFICATION. Note the irregularlinear 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 Reiters syndrome patients

AP radiograph of the lumbar spine with reactive arthritis demonstrates a paraspinal ossification bridging the L2 and L3 vertebrae.

Erosive OsteoarthritisInflammatory variant of degenerative diseases involving the interphalangeal joints of the hands.Common in females 40-50 years old.The onset of erosive osteoarthritis is characterized by episodic and acute inflammation of the DIP and PIP joints of both hands in a symmetric manner.Pain, edema, redness, nodules, and restricted motion are found at the involved articulations of the hands.The Pathological features are cartilage degeneration and synovial proliferation.

Radiologic FeaturesInvolvement of the ulnar compartment of the carpus is significantly spared differentiating involvement from rheumatoid arthritis.Radiographic changes are characterized by osteophytes, loss of joint space, and sclerosis. Osteophytes are identical to those seen in DJD.They are marginal in origin, taper distally, and are often larger at the distal articular component.Loss of joint space is usually non-uniform, with adjacent subchondral sclerosis.Superimposed changes of erosions, periostitis, and ankylosis on these degenerative features are characteristic of erosive osteoarthritis. Bone erosions are distinctively centrally located on the proximal articular surface and more peripherally at the distal articular surface.

Radiologic FeaturesAt DIP and PIP joints of hands.Erosions (gull wings sign), sclerosis, osteophytes, periostitis (mouse ears sign), ankylosis, and non-uniform loss of joint space.

Gull Wings Sign. Shows characteristic biconcave articularcontour (arrows).

Radiograph of both hands shows erosions of the distal interphalangeal joints with typical gullwing configuration due to central erosions and peripheral osseous proliferation

HANDS. A. Target Distribution. Note the selective involvement ofthe distal interphalangeal joints (arrows). B. Radiologic Features. Shows on closer inspection of these involvedjoints reveals osteophytes, sclerosis, loss of joint space, cystic erosions, and deformity.

Differential diagnosis The main differential considerations are rheumatoid arthritis, psoriasis, and non-inflammatory degenerative joint disease. Rheumatoid arthritis rarely involves the distal interphalangeal joints and has a positive latex test. Psoriatic arthropathy is characterized by discrete marginal erosions with adjacent fluffy periostitis (mouse ears sign). Non-inflammatory DJD will show no erosions but will otherwise appear identical to erosive osteoarthritis.

METABOLIC ARTHRITIS GoutDisorder of purine metabolism in which hyperuricemia leads to deposition of sodium monourate crystals into cartilage, synovium, periarticular, and subcutaneous tissues.These crystals evoke a strong inflammatory arthritis usually in the lower extremity.Affects males 20:1, usually in the 4th and 5th decades.Four stages apparent: asymptomatic hyperuricemia, acute gouty arthritis (especially at the first metatarsophalangeal joint), polyarticular gouty arthritis (chronic, long-standing disease), and chronic tophaceous gout (soft tissue accumulations of sodium monourate).Accumulation of these crystals (tophi) results in synovial pannus, bony marginal erosions, cartilage degradation, and bone destruction.

Radiologic FeaturesGeneral features include dense soft tissue tophi, preservation of joint space, bone erosions (marginal, periarticular overhanging margin sign, intraosseous) normal bone density, periosteal new bone, secondary degenerative joint changes, chondrocalcinosis, and avascular necrosis.The most frequently targeted areas of involvement are the first metatarsophalangeal joint, other metatarsophalangeal joints, the hands, and wrists.Spine and sacroiliac articulations show infrequent erosions. Occasional epidural tophi occur leading to compression myelopathy.

Xray foot shows Asymmetric periarticular erosions that spare part of the joint are typical of gout arthritis, seen here involving the first metatarsophalangeal joint of the right foot. Note the characteristic overhanging edge at the site of erosion (arrows) and the soft-tissue mass representing a tophus (curved arrows); osteophytes and osteoporosis are absent, and the joint is partially preserved (open arrow).

Demonstrating a classicoverhanging margin sign (arrow), periarticular erosion (arrowhead), and intraosseous erosion (crossed arrow).

PA Foot. Show the soft tissue swelling in a juxta-articular position about the great toe. The tophi have calcified with juxta-articular erosions and relative preservation of the joint space. This is the characteristic plain film finding of gouty arthritis

B. T1-Weighted MRI, Coronal Foot. C. T1-Weighted MRI, Sagittal Foot. Show the low signal intensity in the areaof the tophi erosion of the bony structures, which correlates with the plain film findings. The signal intensity in gouty tophi is low on T1- and T2-weighted images.

A.Fingers. Note the large tophi and erosive changes. B. Hand. Shows multiple areas of bone destruction owing to the presence of tophi. A large intraosseous tophus is seen in the second digit (arrow). Numerous erosions are also visible in the carpal bones, creating the spotty carpal sign(arrowheads).. C. Spotty Carpal Sign. Note that multiple carpal erosionshave resulted in this appearance. D. Metacarpal Destruction. Observe that at the base of the metacarpalsextensive bony destruction has occurred from adjacent tophi (arrows). E. Radioulnar Erosion. Note the large erosive excavations at the distal radius and ulna (arrow). The outline of the adjacent tophus can be seen (arrowhead).

Calcium Pyrophosphate Dihydrate Crystal Deposition Disease (Pseudogout) An inflammatory joint disease caused by deposition of CPPD into the synovial fluid, linings, and articular cartilage.Usually more than 30 years of age, with a peak at 60 years with equal sex distribution.Acute presentations (20%) may simulate gout or rheumatoid arthritis with swollen, hot, tender joints; usually affects knees, wrists, and hands, with attacks lasting 1-7 days.Chronic presentations (60%) simulate degenerative with bony swelling, crepitus, and stiffness.The pathological features is crystals deposition into the chondrocyte lacunae within articular cartilage due to which chondrocytes subsequently die, resulting in impaired cartilage replacement and maintenance, followed by thinning and cracking, simulating DJD.

Radiologic FeaturesBasic radiographic signs are soft tissue calcification and pyrophosphate arthropathy. Cartilage calcification (chondrocalcinosis) is the most common radiographic sign of CPPD crystal disease in the knees, wrists, symphysis pubis, elbows, and hips.Fibrocartilage is shaggy and irregular (knee menisci, wrist triangular cartilage, symphysis pubis).Hyaline is thin, linear, and parallel to and separated from the adjacent subchondral bone (wrist, elbow, shoulder, knee, hip); additional calcification in capsule, synovium, ligaments, tendons, and blood vessels

Pyrophosphate arthropathy is most common in the knee, wrist, and metacarpophalangeal joints.Articular changes simulate DJD, except unusual articular distribution, unusual intra-articular distribution, prominent subchondral cysts, bone destruction, and variable osteophyte size.The knee is the most commonly involved joint radiographically and clinically. Chondrocalcinosis of menisci,Intraarticular osseous and calcific bodies are common. Diagnosis strongly suggested if patellofemoral joint is selectively and/or severely involved.In the wrist, chondrocalcinosis of the triangular fibrocartilage and the hyaline cartilages of the entire carpus. Advanced and exuberant degenerative changes in the radiocarpal compartment. Scaphoid moves proximally and the lunate moves distally (stepladder appearance).

A. Diagram.Chondrocalcinosis can be seen in either the fibrocartilage (FC) or hyaline cartilage (HC). B and C. MeniscalChondrocalcinosis (arrows). D. Calcification. Note the calcification in the meniscus (arrow), hyaline cartilage (arrowhead), and synovial membrane (crossed arrows).

Chondrocalcinosis of the triangular ligament

Multiple cysts

WRIST. A. and B.Chondrocalcinosis. Note the calcification within the triangular cartilage (arrows) and intercarpal hyaline cartilageC. Subchondral Cysts. Note the cysts within the lunate and scaphoid, with Chondrocalcinosis. D. Scapholunate Dissociation (Terry Thomas Sign). Observe that the scapholunate space iswidened (arrow). E. Scapholunate Advanced Collapse Deformity. Observe the large subchondral cysts within the radius and carpus (arrow). Observe that the lunate has rotated anteriorly, as noted by its triangular shape (piesign) (arrowhead). There is widening of the scapholunate space (crossed arrow).

Calcifications at the MCPs

INFECTIOUS ARTHRITIS-PYOGENICSeptic Arthritis:-Most common route of joint contamination is hematogenous spread or direct traumatic implantation.Single joint involvement is seenThe most frequently isolated organism is Staphylococcus aureus.The clinical feature are Chills, fever, edema, pain, and redness with Altered gait and a painful limp are common in weight-bearing joints.The pathological feature are purulent exudate creates joint distention,Cartilage destruction leads to osseous destruction and loss of joint space,Regional hyperemia leads to juxta-articular osteoporosis.

Radiologic FeaturesThe knee and hip are the most common sites.Joint effusion leads to distortion of the fat folds.Positive Waldenstrms sign.Rapid loss of joint space; loss of the cortical white line and moth-eaten pattern of bone destruction.Bony ankylosis rarely occurs.

Waldenstrms signAn early sign of septic hip joint disease is an increase in the articular joint space between the femoral head and Khlers teardrop (the inferior and medial surface of the acetabulum). This measurement is taken from the lateral aspect of Khlers teardrop to the medial margin of the femoral head; a measurement > 11 mm or a difference in Measurement > 2 mm, compared with theopposite hip, is a positive sign and is considered clinically significantNote:-NOT specific for infection can aslo be seen post traumatic and synovial imflammatory condition

Xray shows complete loss of joint space at the third metatarsophalangeal articulation. This loss of bone density is present on both sides of the joint. The early lesion of septic arthritis is loss of the normal subchondral cortical white line (arrowhead) in the involved third metatarsal head. Note the normal cortical white line (arrows) in the second and fourth metatarsal heads.

Anteroposterior radiograph shows extensive destruction of the right femoral head and neck and right acetabulum consistent with septic arthritis

SEPTIC ARTHRITIS WITH PROGRESSION. A. Initial Film. Note the prominent soft tissue swellingof the entire digit (arrow). Slight bone destruction is evident (arrowhead). B. 1-Month Follow-Up. Shows marked soft tissue swelling of the entire digit (arrows). Moth-eaten destruction of the middle and distal phalanx isevident (arrowheads).

(A) Dorsovolar radiograph of the right wrist shows destruction of the radiocarpal joint and erosive changes of the distal radius, distal ulna, lunate, and scaphoidbones. Note also involvement of the carpometacarpal articulation. There is periosteal reaction of the distal radius and ulna and soft-tissue swelling.

(B) Coronal three-dimensional (3D) (GRE) fatsuppressed (left part) and coronal proton density-weighted fat-suppressed (right part) MR images demonstratean erosion of the distal ulnar(arrow) with a radiocarpal joint effusion extending to the distal radioulnar joint through a complete tear of the triangular fibrocartilage. Note the intermediate-to-low signal intensity of most of the effusion and mild surrounding soft-tissue edema (arrowheads) consistent with synovitis due to septicarthritis.

INFECTIOUS ARTHRITIS-NON PYOGENICTuberculous Arthritis:-Tuberculosis involving the weight-bearing appendicular joints is second only to the preferred spinal site with monoarticular involvement The hip and knee are the most common sites (representing 75% of cases), with the ankle, shoulder, elbow, pubes, and wrist being rarely involved.Most patients are middle-aged or elderly, and many have received multiple intra-articular injections of steroids for a pre-existing unrelated joint disorder.The tubercle bacillus may lodge in the synovium or the metaphyseal portion of the bone. Most tubercular arthritic lesions begin within the metaphysis as an infectious focus with secondary spread to the joint

With this mode of presentation the inflammatory changes in the synovial membrane are extensive, leading to significant early joint effusion.The infected synovial membrane becomes thickened, and granulation tissue spreads to the free surface of the articular cartilage. This interference with the free surface of the articular cartilage affects its nutrition and ultimately leads to its destruction.Early erosions occur involving the portion of the proximal femur that is bare of cartilage but exposed to synovium. Thus the initial erosive lesions may simulate those of early rheumatoid arthritisAs the entire infective process progresses, a non-uniform destruction of the articular surface occurs. As cartilage and bone destruction ensue, sequestrum formation of variable size may occur. This process often involves both surfaces of the joint, leading to the characteristic kissing sequestrum.

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RADIOLOGICAL FEATURESEarly radiographic signs are joint widening, which is secondary to joint effusion and distention, and soft tissue swelling.This is followed by destruction of the subchondral cortex (cortical white line) and a moth-eaten pattern of bone destruction, often on both sides of the joint,Later, narrowing of the joint occurs as the articular cartilage and bone are destroyed. The entire process is accompanied by juxta-articular osteoporosis, which occurs as a result of hyperemia and disuse atrophy.A triad (Phemisters triad) of radiographic findings exists and is characteristic of tuberculous arthritis: progressive and slow joint space narrowing, juxta-articular osteoporosis, and peripheral erosive defects of the articular surfaces.

The end stage of tubercular arthritis is fibrous ankylosis of the joint. Bony ankylosis is rare in tuberculosis, but it is a common sequela of pyogenic arthritisA peculiar complication of tubercular arthritis in the knee is a focal overgrowth of the medial epiphysis, creating a megacondyle, as a result of localized hyperemia. This sometimes mimics a similar appearance of the medial condyle in Stills disease and hemophiliaSacroiliac joints:-The presentation is usually unilateral. (Fig. 12-67) A pseudo-widening of the joint, early osteolytic destructive lesions, and eventual ankylosis are the cardinal roentgen signs.

A. AP Hip. Note the extensive resorption of the entire femoral head, with lateral displacement of the femur. Observe the destruction and disorganization of the acetabulum. This is anadvanced stage of tuberculosis of the hip. Showing the solid periosteal new bone formation on the diaphysis of theproximal femur (arrows). B. AP Knee. Note the symmetric narrowing of the joint space about the knee articulation. Observe the destruction of the articular cortex of the distal femur (arrows). These represent relatively early signsof tubercular arthritis.

KISSING SEQUESTRUM: HIP JOINT. Shows the complete resorption of the femoral head, with extensive destruction of the articular cartilage. Note the lateral displacement of the femur from the acetabulum. There are many bony sequestra scattered throughout the acetabular and femoral head area. An extensive degree ofsequestered debris is noted in the area of the greater trochanter.

Anteroposterior (A) and lateral (B) radiographs of the elbow demonstrate a large joint effusion, as indicated by positive anterior and posterior fat pad signs on the lateral projection. Small periarticular erosions are not clear on these views. (C) CT section shows narrowing of the joint and peripheral erosions typical of tuberculous infection.

PAbradiograph of the left wrist and hand shows advanced arthritis involving the left carpus. There is complete destruction of the radiocarpal, ,midcarpal and carpometacarpal articulations as well as whittling and sclerotic changes in the distal radius and ulna. Note the osteoporosis distal to the affected joints and the soft-tissue swelling.

NEUROTROPHIC ARTHROPATHYNeurotrophic arthropathy is a destructive articular disease that occurs secondary to a loss or impairment in joint proprioception.Subsequently, the involved joint undergoes premature and excessive traumatic degenerative changes that lead to severe destruction and instability.Distinct lack of objective and subjective pain despite joint swelling, instability, and crepitation.Absent deep reflexes, analgesia, ataxia, and serology (possibly) positive for underlying pathological cause.The pathological features are loss of the normal protective nervous reflexes leads to lax ligaments and muscles and abnormal joint mechanics result in rapid and excessive degeneration of articular cartilage, hypertrophic spurs and bone formation, fractures, and complete joint disorganization.The underlying conditions leading to neuropathic joint include diabetes mellitus, syphilis, leprosy, syringomyelia, and congenital indifference to pain.

RADIOLOGIC FEATURESTwo basic types: hypertrophic and atrophic.Hypertrophic: classic type in which bone production is the dominant feature and summarized as the six Ds:Distension: earliest finding owing to effusion.Density: increase in subchondral bone sclerosis.Debris: bony intra-articular fragments.Dislocation: joint surfaces often malaligned.Disorganization: joint components usually disrupted (bag of bones).Destruction: articular bone shows loss of bone substanceUsually predominates in the weight-bearing joints such as the lumbar spine, hips, knees, ankle, and tarsus

Atrophic: may follow hypertrophic phase or occur as an isolated finding, and is especially more common in the shoulder, hip, and foot.Articular ends of bone may appear surgically amputated or tapered like a licked candy stick; absence of six Ds.Spine: usually lumbar region, with large osteophytes, prominent sclerosis, advanced discopathy, severe subluxations, and body fragmentation.Knee: hypertrophic featuressclerosis, debris, destruction, and dislocation.Foot: hypertrophic, especially in subtalar joints. Atrophic in forefoot, especially in metatarsophalangeal joint region.

Anteroposterior radiograph of the right hip of shows the typical features of neuropathic (Charcot) joint. There is completedisorganization of the joint, fragmentation, and subluxation. The absence of osteoporosis is a characteristicfeature of the neuropathic joint. This condition represents the most severe manifestation of degenerative jointdisease.

A. Hypertrophic Pattern, AP Hip. Observe the density, debris, destruction, and dislocation of the joint. B. Atrophic Pattern, AP Hip. In contrast, observe thatthe femoral head has been resorbed, with a distinct lack of debris.

NEUROTROPHIARTHROPATHY: ATROPHIC FEATURES. A. Syringomyelia, Shoulder. Note the amputated appearance to the humerus. B. Diabetes, Foot. Shows that the distal metatarsals are tapered, producinga licked candy stick configuration.

NEUROTROPHIC ARTHROPATHY: PROGRESSIVE CHANGES WITH SYPHILIS. LUMBAR SPINE. Initial Study. Note that degenerative changes are visible with osteophytes and loss of disc height. B. 3-Year Follow-Up. Note that advancement of the degenerative changes is most prominent at L2 and L5. C. 6-Year Follow-Up. Observe the severe discovertebral joint destruction with sclerosis and bony debris at the L2-L3 level.D. 9-Year Follow-Up. Note that the process has extended to the remaining lower lumbar levels with progressive collapse of the lumbar vertebral bodies.E. 10-Year Follow-Up. Observe the complete destruction of vertebral bodies and intervertebral disc spaces with exuberant bone formation and debris, completing the process

NEUROTROPHIC ARTHROPATHY: DIABETES. FOREFOOT. A. Early Atrophic Changes. Note the tapered contour of the second and third metatarsal heads. Note the vascular calcification frequently seen in diabetic patients. B. Later Changes. Observe that the tapered configuration is easily identified in association withosteolysis of adjacent bones.

CONNECTIVE TISSUE ARTHRITISSystemic Lupus ErythematosusGeneralized connective tissue disorder involving multiple organ systems.Women of childbearing age affected.Onset with fever, malaise, skin rash, and arthralgias.The pathological features are Immune complexes and fibrinoid material are deposited in body tissues, resulting in inflammatory changes in blood vessels, synovium, and serous membranes.

Radiologic FeaturesMost prominent features visible in the hands.General features are reversible subluxations, dislocations and deformities, normal joint spaces, osteoporosis, osteonecrosis, soft tissue atrophy, and calcification.Hand: ulnar deviation, boutonniere, and swan-neck deformities; Spine: atlantoaxial instability; steroid-induced compression fractures.

(A) Typical appearance of the thumb SLE. Note subluxations in the first carpometacarpal and metacarpophalangeal joints without articular erosions.(B) the oblique radiograph of her left hand shows dislocations at the first carpometacarpal joint and distal interphalangeal joint of the index finger (arrows), and subluxations in the metacarpophalangeal joints of the index and middle fingers associated with swan-neck deformities

SYSTEMIC LUPUS ERYTHEMATOSUS: DEFORMITIES. A. PA Hands. Note the complete dislocationof the metacarpophalangeal joints, swan-neck deformities of the fingers, and boutonniere configuration of thethumbs bilaterally. B. Hands. Same patient with hands placed firmly on the cassette. Note the reversibility of alldeformities.

These deformities are reversible owing to the tendinous and ligamentous laxity, but will reappear immediately once the hand is moved

SclerodermaSystemic inflammatory connective tissue disease affecting the skin, lungs, gastrointestinal tract, heart, kidneys, and musculoskeletal systemMore common in females 30-50 years of age.Initial peripheral pain and swelling, with high incidence of Raynauds phenomenon.The pathological features are low-grade perivascular inflammation with atrophy and fibrosis of adjacent collagen.

Radological featuresHand is most commonly involved Soft tissue:-tapered, conical fingertips ,retraction of fingertip,loss of overlying skin folds ,calcification: skin (calcinosis cutis) intra-articular.Bone:-Resorptiondistal tufts(acroosteolysis)Joint:-Erosive arthropathy at first metacarpal-carpal joint

SCLERODERMA WITH DIGITAL SKIN RETRACTION AND EARLY ACROOSTEOLYSIS. Note the atrophy and retraction of the soft tissues of the fingertip at the fourth digit (arrows). Resorption of the distal tuft is also seen (arrowhead). The combination of these two findings is highly indicative of scleroderma.

SCLERODERMA:DIGITAL PATTERNS OF CALCINOSIS CUTIS. A. Punctate. B. Sheet-Like.