Imaging (c)

Blue writing is what I added to these notes NORMAL

ABNORMAL

NV/CA

CONGENITAL DYSPLACIAS

ACQUIRED TRAUMA S.T MONO

TUMOR

PATHOLOGY BONE JOINT POLY

INFECTION SYSTEMIC (BLOOD & ENDOCRINE)

Radiology of Skeletal Trauma Introduction Clinicians and Radiologist Confront Dilemmas in the Trauma Patient 1. Recognition of the injury 2. Communication of findings utilizing proper terminology Diagnostic techniques in Musculoskeletal Trauma Non Invasive Invasive Radiography Skeletal Scintigraphy = Bone Scan (reverse x-ray) Conventional Tomography Myelography (iodine into CSF) Computed Tomography (CT) Arthography Ultrasound (no use in chiropractic) CT + contrast Magnetic Resonance Imaging (MRI) Angiography Thermography (no use in chiropractic) MRI + contrast (90 % accuracy) Definitions and biomechanical principles • • • • • •

A fracture is a complete or incomplete break in the continuity of bone or cartilage Bone is anisotropic; it has different mechanical properties when loaded in different directions. Adult cortical bone withstands the greatest stress in compression, less in tension, and the least with shear loading. When force is applied to bone, contraction of muscle alters the stress distribution and may allow the bone to support higher loads than expected. With greater speed of loading, more energy is stored before failure; with fracture, this energy is dissipated rapidly, resulting in extensive soft tissue damage. Repeated loading reduces the amount of total weight a bone can withstand owing to fatigue of muscles that normally redistribute the stress. A surgical defect (e.g. screw hole or site of bone reaction) concentrates stress and decreases bone strength significantly: Such lesions are termed stress raisers.

Fracture Terminology (long and short bones) • •

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•

Open vs. closed fractures. Incomplete vs. complete Incomplete fractures are most often seen in children. Three major types are: Torus (buckling of cortex) Greenstick (fracture of one cortex) Bowing (acute plastic bowing) – least common Complete fractures generally can be described as: Transverse Oblique Spiral Longitudinal Comminution A fracture, that produces more than two fragments. Subsets include: Butterfly Segmental Position

Description of site, either by anatomic landmarks or by dividing long bones into thirds. A fracture located near an articular cortex should be designated either as intra or extra-articular.

•

Apposition Contact of the ends of the fracture fragments. Anatomic (refer to distal end in relation to the proximal end) Displaced: anterior, posterior, lateral or medial or a combination of these. Lack of apposition • Alignment Relationship of the long axes of the fracture fragments. Angulation is the loss of alignment; the direction of angulation is best termed fracture apex or the direction of the displacement of the distal fracture fragment may be specified Varus angulation Valgus angulation • Rotation (only relevant in emergency situation) Both proximal and distal joints must be included on the same film for proper evaluation Special Features Impaction Depression Compression Associated Abnormalities

•

Fracture with associated dislocation Fracture with associated diastasis Additional Terms Chip fracture Avulsion fracture Compression fracture Subluxation Dislocation Stress fracture Fatigue Insufficient Pathologic fracture

Fracture complications to watch out for: • • • • • •

Avascular necrosis Nonunion: may be hypertrophic or atrophic Gas gangrene and osteomyelitis Hardware failure Reflex sympathetic dystrophy Malunion

Fractures in childhood are unique in three ways: • •

•

The bones are more porous, often resulting in incomplete fracture There is greater potential for remodeling malaligned fractures depending on: Number of years of growth left Fracture near the growing end of the long bone Whether the angular deformity is in the plane of movement of the adjacent joint The epiphyseal plate is the weakest and one of the most easily fractured sites in the long bone

Salter-Harris Classification of Slip Chip Crack Slip Chip Crack Crush

Salter-Harris Classification of Epiphyseal injuries • • • • •

Salter1: Fx through the plate itself Salter 2: Fx through the plate and extending through the metaphysis Salter 3: Fx through the plate and extending through the epiphysis Salter 4: Fx through the epiphysis physis and metaphysis Salter 5: Crush injury to the epiphyseal plate. Rare; high complication rate.

Shoulder Trauma Fracture of Proximal Humerus •

•

Neer classification: One part fracture: non-displaced or minimally displaced fracture (80% fracture) Two-part fracture: only a single segment is displaced in relation to the other parts (15% of fracture) Three-part fracture: two segments are displaced with relationship to the other parts (3-4% of fractures) Four-part fracture: all segments are displaced (3-4% of fracture) Complications of these intra-articular involvement in humeral fractures include: Lipohemarthrosis Osteo-cartilaginous intra-articular fragments Inferior displacement of humeral head (pseudosubluxation or drooping shoulder) and/or hemarthrosis and/or atony of deltoid or rotator cuff muscle Osteoarthritis and heterptopic bone formation in pericapsular soft tissue structures

Shoulder Dislocation •

Common site of dislocation is due to shallowness of this joint (glenohumeral articulation). There are three types of shoulder dislocation: - Anterior Posterior Inferior

Anterior Dislocation (95%) • • • •

Humeral head moves anteriorly, medialy, and inferiorly Posterolateral aspect of humeral head impacts anterior-inferior aspect of glenoid: Hill-Sachs deformity of Hatchet deformity The corresponding chip fracture seen as anterior inferior rim of glenoid is called: BANKART lesion Either Hill-Sachs or Bankart lesion may be seen acutely (30%-40% of cases) or after recurrent dislocation

Posterior Dislocation • • • •

Usually due to epileptic seizures, shock therapy or severe blow to anterior aspect of shoulder Direct posterior displacement with superior or inferior change in alignment 50% are not recognized initially Radiographic signs: - Through Sign (“reverse Hill-Sachs” deformity) Chip fracture of posterior rim of glenoid fossa (“reverse Bankart lesion”) Rim sign

Inferior Dislocation (Luxatio erecta) • •

Rare (1% of all dislocations) Articular surface of humeral head dislocates entirely inferiorly to glenoid with fixed abduction of arm. Resulting in arm held over patient’s head. Caused by direct and severe axial blow to shoulder joint - Associated injuries to look for include: > Tearing of inferior aspect of capsule > Fracture of greater tuberosity > Fracture of acromion > Chip fracture inferior to glenoid fossa

Rotator Cuff Tears • • • • • • •

Supraspinatus muscle and tendon occupies space between the humeral head and acromion process. This is the most common rotator cuff tendon to be injured. Radiographic (plain film) changes are most noticeable with chronic case. In the acute cases clinical information may prove to be more useful. Diagnostic imaging of acute tears rest on shoulder arthrography and/or MRI. Chronic tear radiographic changes are due to secondary changes of acromion and humeral head and related soft tissue changes. Elevation of humeral head causing decreased in acromial soft tissue space. Must be seen on both internal and external rotation. Rough measurement is if space is < 0.6 – 0.7 cm. Inferior surface of the acromion becomes flat or concave and sclerotic due to repeated traumatic apposition of the humeral head. In RA or other diseased joints the surgical neck may impact against the inferior glenoid labrum causing mechanical erosion and even an occasional fracture of the surgical neck.

Shoulder Impingement Syndrome: • •

Impingement of the greater tuberosity and soft tissues on the coracoacromial ligament arch, during abduction of arm. Secondary signs include: Spur arising from acromion process Flattening and sclerosis of the greater tuberosity Syndrome may be reproduced under fluroscopy Seen in young and old patients Presentation similar to rotator cuff tear May progress to tendonitis or rotator cuff tear Diagnosis is made with MRI

MRI Anatomy of the Shoulder AC joint is ALWAYS assessed by lining up the bottom of the acromium and the bottom of the clavicle - Should line up straight B/w the humeral head and the bottom of the acromium is the subacromial space - should be > 7mm - houses the supraspinatus muscle and tendon Coracoacromial ligament is important to asses and can only be done by MRI - keeps long head biceps tendon and supraspinatus tendon from sliding too far forward

Minimal MR imaging protocol • • • • • • •

All three anatomical planes imaged Oblique coronal plane (FSE) T1 & (FSE) T2 with fat suppression - (Perpendicular to the oblique sagittal plane) Oblique sagittal plane FSE T2 with fat suppression - (Perpendicular to the oblique coronal plane) Axial plane gradient recall echo (GRE) T2* Field of view (FOV) between 12 to 16 cm Slice thickness 3 to 4 mm Matrix 256x256

MRI of the Shoulder • • • •

Accurate examination Current gold standard for evaluated internal derangement of shoulder The oblique coronal and sagittal plane are require Dedicate shoulder coil is extremely important in the shoulder where high resolution is crucial

MRI of the Shoulder Indications: • • • • • • • • • • •

Shoulder pain non-responsive to conservative careN\ • No improvement with in the first two weeks Detection & staging of rotator cuff tears Detection & staging of rotator cuff degeneration Supraspinatus impingement syndrome Subacromial bursitis Articular anatomy after an osseous fracture Glenohumeral ligament injuries Coracoclavicular & acromioclavicular separations Glenohumeral instability & labral tears Post-operative evaluation Loose bodies &/or synovial tumors (PVNS, SCM, synoviosarcoma)

Rotator Cuff Disease •

• • • •

Supraspinatus • Most common rotator cuff involved clinically • Most commonly rotator cuff to be surgically treated • Unique anatomy predisposes it to trauma & degeneration • Area right under acromion is the “critical zone” where there is the least blood supply. As arm is abducted the bursa prevent wearing on the acromion but if bursitis or arthritis DJD starts to wear Infraspinatus Teres minor Subscapularis Supraspinatus - Most common rotator cuff involved clinically - Most commonly rotator cuff to be surgically treated - Unique anatomy predisposes it to trauma and degeneration - Tendons and ligaments should be BLACK (on MRI)

Impingement syndrome • • •

Impingement of supraspinatus tendon in critical zone during abduction Tendon impacts between anterior acromion and greater tuberosity Aggravating factors Osteophytes from inferior surface of acromion Hypertrophy of AC joint capsule Natural aging of supraspinatus tendon Accelerated degeneration to tendon from poor blood supply Acromion configuration

Rotator Cuff Tears • • •

Type 1: Rotator cuff degeneration tendinosis without visible tears of either surface Type 2: Rotator cuff degeneration or tendinosis with partial thickness tears of either articular or bursal surface Type 3: Complete thickness rotator cuff tears of varying size, complexity, and functional compromise

Incomplete Fxs – torus fx • • • • •

Child or adolescent Easily overlooked! Potential liability Typically not a serious injury, but bone is weak and should be protected to avoid further injury “Buckle” of cortex, typically due to axial loading Common …

Stress Fxs •

• •

Weight bearing bones esp. - 2nd MT - Tibia - Fibula - Calcaneus Healing response is often 1st plain film finding MR very sensitive to marrow edema changes for early Dx.

Stress fractures – “March” fracture • • • • •

Fx healing is first plain film finding 2nd MT most common Seen in army recruits marching with heavy packs Also seen in runners or Pt with altered gait pattern may develop

Stress Fx – Tibia • • •

Runners/joggers Otherwise inactive individuals beginning as aggressive exercise program of walking May be dx as “shin splint”

Spondylolysis • • •

Many (?most?) are the result of stress fx Acute pathogenesis is supported by some Incidence - 3 – 7% in US, with higher numbers in Eskimo population - Incidence rises from age 3 – 20 yrs., then does not increase in frequency - 2:1 male predilection - Increased incidence in association with spina bifida  Seen by some as evidence of congenital etiology, it more likely represents the additional stress created by an open vs. closed ring

• • • • •

L5 most common (67%), then L4>L3>L2 Cervical spine not commonly involved, but C6 predilicted Most often bilateral, but may be unilateral Displacement usually occurs within first two years, if at all Myerding grading - Divide sacral base into ¼ths from back P to A - Into which 1/4 th does a line along posterior aspect L5 vertebral body fall? - Grades I – V; Grade V if spondyloptosis occurs Percent assessment - … May be unstable – flexion/extension may be useful Spondyloptosis may occur “Inverted Napoleon hat” sign on AP view due to overlap of L5 on sacral base Cervical spondylolysis most common at C6 Spina bifida is typically associated Instability may be present

• • • • • • •

Salter – Harris Fx Type I • • • • •

Common locations are distal extremities Easily overlooked without complete series Slipped femoral capital epiphysis (SFCE) is a chronically acquired S-H type I fx Note the tibial physis is closed Offset seen on oblique

Salter – Harris Fx Type II • •

Most common (75%) of Salter – Harris fxs Fx thru epiphysis …

Salter – Harris Type V • • • • •

Easily overlooked! Initial films may be negative - MR much more sensitive! Least common of S – H types Compressive mechanism of injury Early growth plate closure may result in limb-length problems Distal tibia and femur most common

Shoulder – dislocation •

•

95% are anterior - Subcoracoid (most common) - Subglenoid - Subclavicular - Intrathoracic (rarely) Common associated injuries - Hills – Sachs lesion - Bankhart lesion

Shoulder – Hills – Sachs lesions • •

Compression fx of the posterolateral aspect of humeral head from impact against the antero-inferior aspect of the glenoid fossa Creates a “hatchet” deformity

Shoulder – AC joint • • • •

Fall on “point” of shoulder typical hx for AC joint separation Grade I sprain = normal x-rays; clinical diagnosis Grade II sprain = stress views show more than 3 – 4 mm difference in coraco-clavicular space compared to un-injured side Grade III sprain = complete coraco-clavicular ligament disruption evidenced by a 40 – 50% increase in coraco-clavicular space (compared to non-injured side); 5mm or more difference side-to-side

AC joint dislocation • •

Normally AC joint space usually 4 – 5mm max, but up to 8mm may still be normal Alignment of inferior margin of joint more reliable than superior margin

Clavicle Fx •

Location - 75 – 80% of fx occurs in the middle portion of bone > Esp. at junction of outer and middle 1/3’s of bone - Only 5% affect the medial end - 15 – 20% occur at distal end • Fx which leaves the coraco-clavicluar ligament intact are much more stable and more likely to heal Exuberant callus formation of clavicle fx may cause thoracic outlet syndrome Elbow Trauma Normal Elbow Anatomy •

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AP film Normal carrying angle 165 degrees Bowman’s angle describes the normal cubitus valgus in a child and is used to evaluate for abnormal valgus or varus in the presence of a supracondylar fracture Lateral film Radiocapitellar line Fat pads

Elbow Normal variants • • • •

Normal chevron appearance of trabeculae on lateral humerus in the supracondylar region Radial tuberosity in face may simulate neoplasm Supracondylar process may occasionally fracture and cause a median nerve injury Supratochlear ossicle found in the trochlear fossa, to be distinguished from chip fracture

Epiphyseal maturation sequence • • • • • • •

Capitellum: 1 year Radial head: 3 to 6 years Medial epicondyle 5 to 7 years Trochlea: 9 to 10 years Olecranon: 6 to 10 years Lateral epicondyle: 9 to 13 years The timing is not as important as the sequence

Radiocapitellar line •

Draw line on front cortex of humerus should cut capitellum in half and draw line in the middle of the radius should intersect with the other line in the middle of the capitellum

Elbow Fracture in Children • • •

Supracondylar fracture 60%: Almost always have posterior displacement of the condyles and an abnormal anterior humeral line. Lateral condylar 15%: Usually Salter 4, involving the capitellum Medial epicondyle avulsion 10%: May be trapped in the joint; often unrecognized, resulting in severe late disability

Elbow fxs in adults •

• • •

Radial head fxs - Half of all adult elbow fxs - Half are undisplaced, so several views may be required - Esswx-Lopresti fx: a severely comminuted radial head fx associated with subluxation of the distal radioulnar joint. (radial head explodes) Olecranon fx - If distal to the triceps insertion, the fx is widely displaced Transcondylar fxs Intracondylyar T or Y

Dislocated Elbow • • • • •

Eight to 90% are posterolateral Often have associated coronoid process or radial head fxs An isolated dislocation radial head is rare in adults. An ulnar fx (Monteggia’s) must be excluded. Myositis ossificans is a relatively frequent complication Nursemaid’s elbow: - Traumatic subluxation of the radial head from the annular ligament by sudden extension of the elbow. Radiograph is normal and reduces spontaneously when the forearm is supinated for the AP film

Wrist Trauma •

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Take four views - P – A (see radius and ulna) - Lateral (fat plain of pronator quadratus – should be parallel if bowed out then bad) - Oblique - Scaphoid Distal forearm PA film: normal anatomy Distal radial articular surface tilts 17 toward ulna Distal radial epiphyseal line (may simulate avulsion) Lateral film: normal anatomy Pronator quadratus Distal radius articular surface is angled 10 to 15 degrees volarly

Fracture of the Distal Forearm: • • •

Most common injuries of the skeletal system Most result from a fall on the outstretched hand Age is good predictor of the injury 4-10 years: transverse fracture of metaphysis of the distal radius and ulna 11-16 years: Salter fracture of distal radial epiphysis 17-40 years: fracture of the scaphoid >40 years: Colles’ fracture

Transverse Metaphyseal Fracture seen in Children: • •

Complete or incomplete If incomplete, may be greenstick or torus • Salter fxs of the distal radial epiphysis • Salter 2 is most common • Usually only seen on the lateral because often displaced dorsally • The weakest point of the distal forearm is the growth plate b/w 11- 18 years

Distal Radioulnar Dislocation • • •

Abnormal position of the ulnar head Diagnosed by CT Often occurs with Colles’ or Galleazzi’s fracture

Distal Radial Fractures in the Adult •

Colles’ Most common More common in females with senile osteoporosis - Associated with fractures of the proximal humerus and hip - Apex volar angulation with dorsal impaction Intra-articular component Ulnar styloid fracture Silver fork deformity

Other Distal Radial Fractures of Adults • • • •

Smith: Reverse Colles’, with apex dorsal angulation Barton’s: Intra-articular fracture of the dorsal lip of the radius; the carpus follows the dorsal fragment. Unstable fracture requires fixation. Reverse Barton’s: Intra-articular fracture of the volar lip of the radius. Hutchinson’s or chauffeur’s: Intra-articular fracture of the radial styloid process.

Normal Anatomy of the Carpus (PA) • • •

Proximal & distal rows bridge by scaphoid Width of joint space is uniform 3 parallel arcs Proximal carpal row (proximal margin) Proximal carpal row (distal margin) Distal carpal row (proximal margin) Figure 3.9 pg 189 and 3.13 pg 192 Manister

Carpal Bones •

Frequency of carpal injuries Forearm injuries are 10 times as frequent as carpal Rare in patient under 12 years 60-70% are scaphoid fractures

Scaphoid fractures: • • •

•

70% at waist and nondisplaced Early diagnosis can be made with tomograph, bone scan or MRI Unique blood supply allows for increase incidence of complications: Delayed union Nonunion - AVN of proximal pole (30%) - Prisers Scaphoid waist fractures may take up to two year to unite. Although nonunion radiographic signs are common, 90% of scaphoid fractures unite eventually.

Lunate Fractures • • •

Unusual to see in acute cases Vulnerable to AVN (Keinboch’s disease) Ulnar minus variant (ulna does not grow long enough) - Ulna should be same length as radius +/- 2mm

Carpal dislocations • • • •

Perilunate dislocation: The capitate articular surface is dislocated from the lunate (almost invariably dorsally); the lunate maintains its normal articulation with the radius Lunate dislocation: - The lunate has lost its articulation with both the capitate and radius and is displaced volarly with 90 degrees rotation. The capitate remains aligned with the radius but sinks proximally. Pg 90 –92 pink book SLAC (Scaphoid Lunate Articular Collapse)

Carpal Instabilities • •

Ligamentous injury can give instability patterns without frank dislocation. Radiographic examination PA: look especially for a diastasis at the scapholunate joint and lunate tilt. Lateral: Note the previously discussed coaxial relationship. Lunocapitate angle (< 20 degrees) Scapholunate angle (30 to 60 degrees)

Hand Trauma Finger Fracture • • • •

• •

Tuft fx: crush injuries Shaft fx: usually angulated Avulsion fx: usually dorsal or volar aspect Baseball (mallet) finger - Due to flexion of a forcibly extended finger - Site of inspection of the common tendon (extensor) - Results in a tendon injury or avulsion fx at the base of the distal phalanx Boutonniere (buttonhole) deformity Due to PIP flexion with DIP extension and rupture of the middle slip of the extensor mechanism Avulsion of the dorsum of the base of the middle phalanx is unusual but may occur Volar plate fractures: Proximal base of the phalanx Volar side of base of middle phalanx

Collateral (radial and ulnar) • • • • •

Ligaments may rupture and avulse fragments. Most common is avulsion of the ulnar collateral ligament of the MCP of the thumb “Gamekeepers thumb” – due to valgus injury Common with skiing May be intra-articular Stress views commonly required

Thumb •

NB: standard hand films do not give true AP and lateral views of the thumb and so, are inadequate for thumb trauma: Standard views are as follows: AP: hand fully pronated with the dorsal surface of the thumb held against the film Lateral: hand pronated 15 degrees

Fracture of the first metacarpal •

•

Bennett 1/3 of all first metacarpal (MC) fractures Fractures dislocation with an oblique intra-articular fracture at the base of the MC and dorsal dislocation Usually treated with ORIF Rolando Comminuted Bennett’s fracture Treated with closed reduction since pinning is usually not helpful due to comminution of fracture

Dislocation • •

Phalanx: usually dorsal dislocation produced by hyperextension Carpalmetacarpal (CMC) - Uncommon site for dislocation - 50% involve the fifth MC - 25% involve the 2nd MC - 80% are multiple - 2/3 dislocate dorsally

Metacarpal Fx •

Boxer’s Fx - Usually fifth metacarpal - Apex dorsal angulation is best seen on lateral view

Case Study (DID NOT COVER IN CLASS) Avascular necrosis of femoral head and hip joint Steroids can cause hip disease and avascular necrosis MRI: main view = Scout view – look down cut Depends on ADL to determine if replacement is necessary Can have build up of trabeculae or decreased amount of trabeculae Pathognomonic – hip pain which doesn’t go away 2 weeks to feel better (sprain) Trauma – femoral neck fracture, femoral head Alcoholics – long term Patients on steroids – recreational and treatment Systemic – most common in hip, humeral head, talus, carpal bones Patients with head injuries – hydrocephalus Hemoglobinopathies – disease of blood cells Sickle cell anemia Caisson’s disease – increase oxygen in blood  scuba divers 10–20% AVN etiology unknown Systemic – most common in hip, humeral head, talus, carpal bones Reason for AVN Blood supply to femoral arteries – circumflex arteries Adult supply – goes from distal to proximal 7-30% those with hip fracture have AVN Hip Trauma •

True hip pain is groin pain

Hip Anatomy • •

AP film must show the hip in slight internal rotation. Frog-leg lateral film superimposed the superior border of the greater trochanter over the femoral neck, simulating an impacted fracture line. • Groin lateral is true lateral • Oblique view of the pelvis (Judet view) is useful to evaluate for acetabular fracture or a dislocated hip. • Soft tissues: bulging fat planes may represent a hip effusion, but are not always present or symmetric. They also require a perfectly positioned patient. • Three fat planes are: - Iliopsoas - Gluteal - Internus Otto’s pelvis – bilateral protruding acetabulum • Ward’s Triangle – the weakest part of the femoral neck -> gets larger as we age • To evaluate hip must take hip view NOT LUMBAR VIEW • Kholer’s line should not be touched be femoral head (also should not touch tear drop) Hip Dislocation • • • • • •

A rare result of severe trauma Often associated with femoral shaft fracture Posterior dislocation in most common (90%) In the rare anterior hip dislocation the head is found overlying the obturator foramen Early diagnosis is imperative since a delay in reduction sharply increases the probability of AVN Check for fx of acetabulum and quadrangular plate

Femoral Neck Fracture (Hip Fx) • • •

•

Basicervical: rare Transcervical: rare Subcapital: most common - May be impacted or displaced, complete, or incomplete - AVN is a complication in 8% to 30 % of subcapital fractures because the fx compromises the blood flow from the circumflex artery off the femoral artery Must be concerned for fatty embolism

Intertrochanteric (subtrochanteric) Fractures • • • •

Common fracture, generally in older age group that subcapital fracture Two-, three-, or four part, depending on involvement of greater and lesser trochanters AVN is rare b/c it does not compromise the circumflex artery Avulsion fracture of the lesser trochanter by gluteus minimus - Not common in children or adolescents, as avulsion of the apophysis - If it is found as an isolated fracture in adults, it is usually due to underlying bone pathology

Stress fx of the femur • •

In the proximal or midshaft, it usually involves the medial cortex In the distal third of the shaft, it usually involves the posterior cortex

Slipped capital femoral epiphysis (SCFE) •

• •

Epidemiology Usually 10 to 16 years old Males are more often affected than females Blacks are more often affected than Caucasians Obese persons are more often affected than non-obese persons Bilateral 20% but rarely symmetric SCFE occurs during the years of rapid growth which is also the stage at which is also the stage at which the femoral neck configuration changes from valgus to varus Radiographic appearance on AP film The epiphyseal plate appears wider, with less distinct margins The epiphysis appears shorter A line drown along the lateral femoral neck may intersect a smaller portion of the femoral head A frog-leg later or groin lateral confirms the findings • Treated b y pinning in situ; this yields a varus deformity with a short, broad femoral neck • Complications DJD: Surprisingly, a late occurrence, often 30 years later AVN: in about 10% Chondrolysis: Acute disappearance of cartilage in SCFE, chondrolysis has been associated with pin penetration through the articular cortex. The differential diagnosis is infection

Knee Trauma MR of Knee trauma •

If x-ray is negative buzz phrase is internal derangement of knee

Overview • • • •

One of the most ordered tests in radiology Diagnostic accuracy range 85 – 95% “Road Map” for orthopedic surgery Diagnostic accuracy depends on: High resolution images Proper protocol Knowing the MR signs for internal derangements Knowing the imaging pitfalls  Normal variants  Technical variants Meniscal tear grading • Grade 1 Microscopic tear • Grade 2 Partial tear • Grade 3 Complete disruption Imaging Protocols • • • • • •

Sagittal, axial and coronal planes SE T1, FSE T2, GRE T2* Fat suppression T2 protocols Thin slices 1 to 4 mm 256 x 256 Matrix resolution (bare minimum) Small field of view with dedicated phased array coil T1 Black

Lesion

T2 White

CSF/ Joint fluid

Black

White

Fat

White

darker white

Muscle

Gray

Gray

Cortical bone, Ligaments/Tend, Fibrocartilage

Black

Black

• •

Now T2 uses Fat suppression and the fat is black on T2 Can only use fat suppression on MR’s with 1.5 T or higher (so no “open MR’s”)

Soft tissue in knee trauma •

On lateral film, the fat pad posterior to the quadriceps tendon is divided into anterior and posterior compartments by a soft tissue density, the suprapatellar bursa. In the absence of effusion, the suprapatellar bursa is less than 5 mm wide Suprapatellar lipohemarthrosis indicates an intracapsular fracture, which may be occult.

Tibial Fracture •

Tibial plateau fracture Often seen in auto pedestrian accidents since the plateau is at the height of fenders and bumpers. Eight percent are limited to the lateral plateau since most result from valgus stress. Oblique films may be necessary for the initial diagnosis. Tomography may be required. MRI is very helpful in detecting subtle tibial plateau fractures by identifying intraosseous hemorrhage. In general, depression greater than 1 cm or widely separated (5mm) vertical split ……..

Anterior tubercle apophysis • •

May have multiple ossification centers and appear fragmented. Osternecrosis (Osgood-Schlatters disease) should be suggested only in the presence of fragmentation, soft tissue swelling, and pain.

Stress Fracture of the Tibia • • • •

Common in the proximal tibial shaft. Early, may see faint transverse or oblique lucency within the posterior cortex of the proximal tibial shaft. Later, see transverse band of density and callus formation along the posterior cortex. Radiographic laps of lag of 2 to 6 weeks.

Femoral condyle • •

If intra-articular femoral condylar fracture is present, patient is at risk for AVN. Osteochondrosis dissecans. Etiology unknown but possibly due to repeated minor trauma. Most often involves lateral portion of medial femoral condyle. Most common in adolescents and young adults. Arthrogaphry demonstrate whether the overlying cartilage is intact. MRI is diagnostic.

Epiphyseal Injury of the Knee • • • •

Occurrence is relatively rare about the knee, but complication are frequent Salter 2: 70% Salter 3: 15%: These usually involve the medial condyle and are due to valgus stress. They are undisplaced and often occult. The knee is the most common site of Salter 5 fracture: They are usually seen in the proximal tibia, associated with tibial shaft fracture.

Pelligrini Stiata ??? Patellar Trauma • • • • • • • •

Patellar fracture Sixty percent are transverse, through the mid-portion. These are due to an indirect force. 25% are stellate, due to direct trauma. Vertical much less common. Bipartite or multipartite patella: The fragments are found on the superolateral border and have well corticated margins. They are frequently (80%) bilateral. Ostechondral fracture: Usually from the medial facet, associated with lateral patellar dislocation and seen on the sunrise view. Patellar Dislocation: Usually lateral; tendency is defined by patellar tilt, lateral patellar displacement, and patella alta. Patella Alta: Elongation ……

Imaging Protocol- Sagittal • • •

Cruciate ligaments and menisci Knee external rotated about 5 to 10 degrees FSE T2 WI with Fat Suppression Inversion Recovery GRE T2*

Imaging Protocol – Coronal • • • •

Collateral ligaments Menisco-capsular separation Marrow abnormalities FSE T2 WI with Fat Suppression Inversion Recovery GRE T2*

Imaging Protocol – Axial • • •

Patellofemoral compartment Articular cartilage Medial patellar plica Cruciate ligaments FSE T2 WI with Fat Suppression Inversion Recovery GRE T2*

Internal Knee Derrangement • • • •

• •

Meniscus Cruciate ligaments Collateral ligaments medial collateral attached to medial meniscus Patellofemoral compartment Patella Cartilage of patella Patellar tendon Osseous and marrow abnormalities Most common derrangements: - ACL Medial meniscus Medial collateral

Menisci • • • • •

Fibrocartilage C-shape medial O-shape lateral Low signal on both T1 and T2 (shows up dark on MR) Sagittal and coronal images

MRI Meniscal Derangement Grading Scale • • •

Grade 1 Rounded or amorphous signal that does not disrupt an articular surface (blister) Grade 2 Linear signal that does not disrupt an articular surface Grade 3 Rounded or linear signal that disrupts an articular surface (may merit a surgical consult)

Meniscal Tears • • •

Many different configurations and locations Oblique tear extending to the inferior surface of the PHMM (Post. Horn of Medial Meniscus) is the most common type. 10-20 % of cases cannot determine if high signal changes of meniscus are open tears. (Usually b/c too much time has gone by since injury)

Helms “Bowtie” Meniscus • •

Two consecutive sagittal images of each meniscus that include both anterior horn, body and posterior horn – “Bowtie shape”. Three pitfalls 1. Pediatric knees only one bowtie (under 12) 2. Not consistently seen over 60 3. Proper complete imaging of meniscus

Bucket handle Tear • • • •

Frequently missed by radiologists Vertical longitudinal tear in the inner free edge of the meniscus becoming displaced into the intercondylar notch. Coronal images tear may reveal the meniscus to be shortened and truncated Only one “bowtie” image

Discoid Meniscus • • • •

Large disc-like meniscus Children or young adults M/C in lateral meniscus 3% of the population

Parrot Beak Tears • • • •

Radial tear of the free edge of the meniscus Uncommon tear One of the Bowties shows a small gap Anterior and/or posterior horn triangles will often be rounded instead of pointed

Cruciate Ligaments • • • •

MRI of cruciate ligaments is more accurate than is MR imaging of the menisci 95% accuracy for Grade III tears T2 fat suppressed images are crucial ACL torn more frequently

Collateral Ligaments • • • •

MCL attaches to medial meniscus Meniscocapsular seperation LCL separated by popliteal tendon MCL tears more frequently than LCL due to valgus stress of the knee

Grading • •

Grade 1 Injury (mild sprain) MRI shows fluid or hemorrhage in the soft tissues medial to the MCL Ligament is intact Grade 2 injury (partial tear) High signal in and around the MCL on T2 coronal sequences Partial tearing of ligament is identified • Grade 3 injury Complete disruption of the MCL Heal quite nicely simply with mobilization

Lateral collateral ligament is a Y shape tendon (tendon and iliotibial band) Rarely tears Lateral Collateral • Tree parts Posterior structure – tendon of the biceps femoris Mid structure – true lateral collateral ligament (fibulocollateral ligament) - Anterior structure – … • Lateral collateral ligament is infrequently torn Patella • •

Patellofemoral compartment Patellar tendon

Chondromalacia Patella • •

Focal swelling and degeneration of the cartilage As it progresses it causes thinning and irregularity of the articular surface of the cartilage, and finally underlying bone is exposed

Medial Patellar Plica • • • •

Normal structure over half of the population Embryological remnant Thin fibrous band that extends from medial capsule to medial facet of patella Can thicken and cause clinical symptoms indistinguishable from a torn meniscus

Bony Abnormalities •

Subchondral contusion Bone bruise Subchondral fx that is negative on x-rays

>

Pt should be non-weight bearing (crutches)

Osteochondritis Dissecans • • •

Usually only on medial femoral condyle (lateral side) Pretty common Sometimes hx of trauma or sometimes no hx

ADDED MATERIAL MRI of Ankle Overview • • • •

Anatomy and Technique Tendons Ligaments Osseous Abnormalities

Anatomy and Technique •

• • •

MRI technique - Sagittal FSE T2 with Fat suppression - Axial FSE T1 - Axial FSE T2 with fat suppression - Coronal FSE T2 with fat suppression Dedicated foot/ankle coil Matrix > 256 x 256 3 and 4 mm slices

Tendon • •

•

•

Common reason for MR exam Only few are of pathological importance - Achilles Tendon - Posterior tibial tendon - Flexor hallucis longus tendon - Peroneal tendons Tendons can be directly traumatized or be injured from overuse - Teno-synovitis  Seen on MR as fluid in the tendon sheath with the underlying tendon appearing normal - Tendonitis – Partial tears  Seen as focal or fusiform swelling of the tendon with signal in the tendon that gets bright on T2-WI  Thinning or attenuation of the tendon is seen in more severe forms of tendonitis - Tendon rupture  Identified on axial images by noting the absence of a tendon one or more images Achilles Tendon - Does not have sheath - Tendonitis is commonly seen - Complete disruption:  Athletes  Males 35 – 45  MR used to determine surgery vs. casting

Posterior tibial tendon • • • • • • •

Most medial flexor Inserts on navicular cuneiformus and metacarpals 2 – 4 Helps in support of longitudinal arch Arch problems lead to chronic PTT tendonitis and rupture – common in RA MR distinguishes b/w tendonitis (non-surgical) vs. rupture (surgical) MR shows best on axial images o T1 – WI tendon is swollen and shows signal change o T2 – WI signal in tendon gets brighter Tendon rupture is diagnosed by absence of tendon on axial images at the level of the tibiotalar joint

Flexor Hallucis Longus Tendon • • • • • •

Easily identified since muscle is still attached FHL extend beneath the sustentaculum talus and serves as pulley to plantar flex the foot FHL is the Achilles tendon of foot in ballet dancers due to extreme flexion Ballet dancers and other activities of extreme foot/ankle flexion will typically have tenosynovitis - Seen on FR as fluid surrounding tendon 20% of ankle effusions will show fluid build up in FHL – anatomical connection Rupture on FHL is rare

Peroneus Tendons • • • • • • •

•

Peroneus longus and peroneus brevis - Bound together by superior retinaculum Posterior to distal fibula Principle everter muscles of foot PB inserts on base of 5th metatarsal PL inserts on base of 1st metatarsal “Dancer’s Fx” or “Jones Fx” is an avulsion Fx of 5th metatarsal Disruption of superior retinaculum - Causes displacement of peroneal tendons - Often seen in skiing accidents - Requires surgical correction - Associated with flake fracture of fibula Complete rupture of PB and PL is rare

Ligaments • • •

Small structures require hi-resolution images for MR assessment Medial (Deltoid) Complex Lateral Complex

Deltoid (Medial) Ligament Complex •

•

Superficial fibers - Tibionavicular fibers – anterior - Tibioclacaneal fibers – medial  Strongest superficial component - Superficial posterior tibiotalar fibers - posterior Deep fibers - Anterior Tibiotalar ligament - Posterior tibiotalar ligament  Strongest part of the entire - Deep fibers are covered by synovium, is intraarticular

Lateral Ligaments Complex • •

Superior group - Anterior tibiofibular lig - Posterior tibiofibular lig Inferior group - Anterior talofibular lig – tears 1st - Posterior talofibular lig – tears 3rd - Calcaneofibular lig – tears 2nd

Ligament Injuries • • • •

Most common to lateral side due to inversion trauma Anterior talofibular lig (ATF) most commonly torn ligament ATF inversion is severe enough then the calcaneofibular will tear next followed by the PTF Deltoid ligament rarely tears

Avascular Necrosis • • •

Talar done second most common location for osteochondritis dissecans (knee m/c) MR essential in early identification and staging Low signal T1 and High signal T2

Osteochondiritis dissecans • • • • •

Stage I - Subchondral trabecular compression Stage IIa - Subcondral cyst Stage IIb - Incomplete separation of the fragment Stage III - Fluid around an undetached, undisplaced fragment Stage IV - A displaced fragment

Freiberg’s Infarction • • • • • •

Necrosis of 2nd metatarsal head prior to closure of epiphyseal plate Second decade Repetitive trauma with microfracture at the metaphyseal physeal junction Deformity of metatarsal head Osteoarthritis of the metatarsophalangeal joint result from repeated weight-bearing trauma Check especially if 2nd toe is longer than 1st

Test 2 •

Degenerative (90+ %) Primary OA Secondary OA Spinal degeneration Disc Facets Diffuse Idiopactic Skeletal Hyperostosis (DISH) Ossification Posterior Ligament Syndrome (OPLS) Neuropathic arthropathy

•

Rheumatoid (systemic disorder) RA JRA (Still’s DZ.) Seronegative Inflammatory Spondyloarthropathies Ankylosis spondylitis Reiter’s syndrome Psoriatic arthropathy SLE Scleroderma Biochemical/metabolic Gout Pseudogout (Calcium Pyrophosphate Disease = CPPD)  Hyperparathyroidism (HPTH) Hydroxy Appetite Deposition Disease Wilson’s disease Hemachromatosis (calcific tendonitis) Ochronosis (alcaptunuria)

•

•

•

Infection (septic arthritis) – affects one joint Staphylococcus aureus Tuberculosis Syphilis Tumors/Miscellaneous Synovial sarcoma Pigmented Vilo Nodular Sarcoma (PVNS) Synovial Chondro Matosis (SCM) Chordoma Avascular Necrosis (AVN) – will create significant OA Hemophilia

Distribution is the most important factor for classification (pattern of bone degeneration) Arthritis Chondrocalcinosis – form of calcification of the cartilage (hyaline) Degenerative arthritis – 2nd Ocherenosis Gout Pseudogout – 1st Achromegaly Wilson’s Disease

Two sub–types of Arthritis Soft tissue swelling/nodules Soft tissue calcification Joint effusion Chondrocalcinosis Alignment problems Osteoperosis Diffuse joint loss Central or marginal erosion Articular destruction Subchondral cysts Osteophytes Subchondral sclerois Vacuum phenomena

Degenerative +/+/+ + +/++ ++ ++ ++

Inflammatory ++ ++ ++ + ++ ++ ++ ++ + +/-

Spinal Degeneration And Their Radiographic Presentation Osteoarthritis: Apophyseal (facet) joint; joint-space narrowing subarticular bony sclerosis and hyperthrophy, vaccum phenomena; Oblique Chronic degenerative disc disease (intervertebral disc degeneration): nucleus puplposus; disc-space narrowing subarticular bony sclerosis, vacuum phenomena, small nonbridging osteophytes; lateral Spondylosis deformans: Anulus fibrosus; broad bridging antrolateral osteophytes arising from midvertebral bodies(disc spaces usually normal); posterioranterior, oblique, lateral Diffuse idiopathic skeletal hyperostosis (DISH): entheses; spondylosis deformans involving at least four contiguous vertebral bodies “flowing”, osteophytes, enthesopathies, … Neuropathic Arthritis - vascular or neuropathic loss in joints Diabetes mellitus Neuro- (tertiary) syphillis Syringomyelia/hydromyelia Congenital indifference

Upper Extremities +/+ +

Lower extremities + + +

Robin’s Ch 28 (Musculoskeletal path) subsection on joints ARTHRITIS • • • •

Misnomer due to the fact that it is not an inflammation of joints, better name would be Arthropathy. Arthritis are classified by WHO with help by rheumatologist. Over 100 different kinds About 30 we will cover www.arthritisfoundation.org

Degenerative

Rheumatoid (C.T. Disorders)

Biochemical

Infections

Non-inflammatory

Inflammatory

Inflammatory

Inflammatory

Primary OA (EOA) Secondary OA Spinal - Intervertebral Osteochondrosis - Spondylosis - Osteoarthrosis Extremity DISH Neuropathic Arth. 90%

RA JRA Spondyloarthopathy - AS - Reiter’s Syn - Psoriatic Arth SLE Scleroderma (PSS)

Gout Pseudogout HADD (calcific tendonitis) (Last three are distracters) Wilson’s Ochronosis Hemachromatosis

Staph Aureus - Pyogenic TB - Granulomatus Syphilis Acute vs Chronic

MISC

Trauma AVN Hemophilia Tumors - Synovial sarcoma - PVNS - SCM - Chordoma

Osteoarthritis • • • • • • • •

AKA: DJD Begins in the hyaline cartilage Joints are 99% cartilage and 1% synovial fluid (just enough to allow gliding of the cartilage) Damage to cartilage is permanent As the cartilage is damaged the joint narrows As the joint narrows the capsule becomes lax and the joint loses stability To counteract the instability osteophytes form to tighten the capsule and increase the stability but at the same time decrease ROM OA  ↓ jt space  instability  ↑ bone formation  ↓ROM

RA • •

Autoimmune non-septic infection of pannus Pannus has lytic enzymes and eats away at everything cartilage and bone (bare areas of bone) (part of the bone in the joint that is not covered by the cartilage and does not have periosteum

Infection • •

Most of the time there is only one joint involvement Just like RA except that the infection agent is known and is m/c Staph a.

• •

The bone that touches the cartilage is called subchondral bone When bare area is eroded away then it is called “marginal erosions” --> LYSIS

Gout •

Uric crystals are called birifringent crystal

•

75% is MCP of great toe

The Arthropathies • • •

• •

Degenerative o OA o Diffuse idiopathic skeletal hyperostosis Inflammatory o RA o Seronegative spondyloarthropathies Crystal deposition o HADD o APPD o Gout Infectious Miscellaneous

Degenerative joint disease • • •

AKA “OA” or “osteoarthrosis” A “wear and tear” type of arthritis Confusing terminology o Intervertebral osteochondrosis  Decaying of the nucleus pulposis  Risk disc herniation o Spondylosis deformans  Decaying of the annular fibers  Risk of stenosis o Discogenic spondylosis – don’t use this term o (Please no “Spurs” – unless you’re from Texas)

Intervertebral Osteochondrosis • • • •

Target tissue = the nucleus pulposis Dessication of nucleus leads to o Vacuum phenomenon in IVD space o Decreased intervertebral disc height Primarily affecting the nucleus pulposis Dessication of nucleus leads to o Vacuum phenomenon in IVD space o Decreased intervertebral disc space

Spondylosis Deformans • • •

• • •

Target tissue = annular fibers of disc Key findings = osteophytes on vertebral endplates An osteophyte on an endplate is a spondylophyte o Bone grows out and then curves up at the end o NOTE! Don’t confuse this with syndesmophyte, which typically implies an inflammatory arthritide Marginal location typical Horizontal orientation Disc space is not normally narrowed

Spine DJD – puzzler • • •

Pseudo-fracture appearance in the C-spine Hypertrophic change of uncinate processes Uncinate hypertrophy creates horizontal lucency

• Not sure? Take obliques • Note the ↑ radiopacity of vertebral body • What’s does the D/Dx include for blastic lesions in vertebral bodies Hemispherical sclerosis • • • •

Type III Modic changes Reactive sclerosis of vertebral body adjacent to degerative disc, often with a Schmorl’s node Type I and II Modic changes visible on MR Chapter 6 in Yokum

Spinal Stenosis • • •

Congenital and Acquired Acquired most often due to degenerative joint disease Other causes include: o Pagets o Compression Fx o Neoplasm (bone or ST) o Congenital anomaly

Spinal Stenosis •

Soft tissue elements often as important (or more important) than osseous o Ligamentum flavum thickening o Capsular thickening of z-joints o Synovial cyst of z-joints

DISH – clinical (Diffuse Idiopathic Skeletal Hyperostosis) • • •

Age = typically 6th decade onset; ↑ incidence with age Clinical/radiographic mismatch is common o Often minimal symptoms, other than “stiffness” o Dysphagia may result if C-spine involved Associated clinical o Diabetes mellitus (22%) o Approx 1/3 + HLA B–27 o ESR ↑ in 22% pts o Peripheral joint complaints include “heel spurs” and tennis elbow o OPLL (Ossification of Posterior Longitudinal Ligament) may result in symptoms of cord compression

DISH X-ray characteristics • • • • • •

At lest 4 contiguous levels involved Thick, flowing anterior and/or lateral calcification or ossification No posterior joint ankylosis Relative preservation of IVD height No SI joint erosion or ankylosis Involvement of thoracic spine may mimic ankylosing spondylitis

DISH Peripheral involvement • OPLL

Calcaneal hyperostosis = “heel spur”

• • • • •

May be isolated phenomenon or associated with DISH Cervical spine most often involved May see on plain film Multiplanar imaging necessary for assessment of cord space Cervical cord compression may result in upper motor neuron findings o + Hoffman sign in hand o + Babindki sign (“upgoing toes”) o “Clumsiness” of hand o Pt. May have difficulty walking on uneven ground due to leg spasticity

3-13-03 Osteitis Condensans Illi • • • • • • • • • • •

May/Not have symptoms Typically uni- or multi- parous female pt Childbearing age range Self-limiting condition that resolves with age May be uni- or bi- lateral o More often bilateral Affects the iliac side of SI joints, usually bilateral Affects lower 1/2 of joints Triangular pattern of reactive sclerosis SI joint will not be fused No need for referral Unusual to see in elderly

Seronegative Spondyloarthropathy • • •

• • •

Seronegative? o Serologically negative for Rheumatoid arthritis o Used to be called "rheumatoid variants"; not a currently used term Spondyloarthropathy o Spondylo" = spine o Arthropathy = abnormal findings in the joints Group of disorders including o Ankylosing spondylitis o Psoriatic arthropathy o Reactive arthritis o Previously known as "Reiter’s disease" - eponym currently out of favor Enteropathic arthropathy (Chrohns disease or ulcerative colitis can cause reactive arthritis that looks like ankylosing spondylolysis) The HLA-B27 antigen (human leukocyte antigen) o Ankylosing spondylitis - 90%+ o Psoriatic arthropathy - 50%+ o Reactive arthritis - 75%+

Ankylosing spondylitis • • • • •

Age onset 15-35 yrs o only 10% begin > 39 yrs of age Sex: males > females by 10 or 15:1 ratio Race: white > black 4:1 50% will have radiation of pain to lower extremities at some point - d/dx sciatica 10-50% have extremity joint pain at presentation o Large extremity joints (hip and shoulders) predilicted over small joints

o

Hip involvement est at 17-35%

A S (cont) clinical diagnostic criteria • • • • • •

Lumbar pain/stiffness for > 3 months, not relieved by rest Limited lumbar ROM Pain/stiffness of thoracic area Limited chest expansion History of iritis and iridocyslitis Sacroillitis with any 2 of the above criteria

A S (cont) extra skeletal • • • • • • • • • • • • •

Up to 18% of pts with ulcerative colitis or Chrohns disease will develop ankylosing spondylitis Aortitis Iritis in 25% - may be presenting symptom Pulmonary fibrosis may occur Up to 80% reported to have chronic prostatitis Variable degree of progression o Inflammation may be limited to SI joints o Widespread spinal involvement and disability may occur Classic forward posture and exaggerated kyphosis Bilateral sacroiliac involvement almost always seen Early changes are widening of joint space, erosions and predilection of the lower portion of the joint More change on iliac side- thinner cartilage Later changes involve bony fusion of SI joints "Star sign" may be seen at iliolumbar lig insertion About 50% pts will have complete, bilateral SI joint fusion

A S (cont) (spine) • •

• • •

Early changes in the spine often at the thoraco-lumbar junction Syndesmophytes o Thin, vertical and bilateral calcific/ossific density o Attached to joint margin (marginal :) o Bridging the IVD space, resulting in ankylosis Enthesopathy = inflammation of ligamentous insertions "Shiny corner sign" in spine- precedes syndesmophyte May result in "squared off" appearance of vertebral bodies

Note SI joint problem is confirmation • • • • • •

"Bamboo spine" is late stage, but does not always result Always check for atlantoaxial instability in ANY pt with an inflammatory arthropathy! o Est. 2% of AS pts develop spontaneous C1/C2 instability Predisposition to "carrot-stick" spinal fx, or advanced degenerative change in spinal joints with residual mobility o "Anderson lesion" Peripheral joint symptoms at presentation in up to 50% of pts Large extremity joints predilected (hip and knee) Changes resemble rheumatoid arthritis

Dr Thompson’s Lecture Seronegative Spondyloarthropathy • • • •

AS – most common Psoriatic arthropathy Reactive arthritis (Reiter’s Syndrome) Enteropathic arthropathy – arthritis associated with inflammatory bowel disease (very similar to AS)

Psoriatic arthropathy • • • • • • •

•

•

•

2 – 6 % of pt with psoriasis pt’s have this arthropathy 25% of pt with severe psoriasis Skin changes – silvery, scaly erythematous rash seen on extensor surfaces of forearm, neck, scalp, pubic areas, and knees Nail changes – pitting, discoloration, hyperkeratinosis o 80% of psoriatic arthritis Onset typically 20 – 50 yoa Onset of arthritis may precede skin lesions (up to 20% of time) Serological markers o ↑ ESR o HLA B27 “+” up to 75% is SI joint involved  ~ 30% if only small joints Patterns of involvement (Resnick) o Peripheral arthritis with DIP predilection o Pattern similar to rheumatoid o Asymmetrical oligoarthitis or monoarthritis o Arthritis mutilans o Sacroillitis More prominent features: o Asymmetrical o Joint swelling o Enthesopathy and periostitis o Bony ankylosis of interphalangeal joints Syndesmophytes o Asymmetrical o Coarse o Non-marginal o May be “comma-shaped” o Not as vertical as AS o Indistinguishable from Reactive arthritis o Often begin T–L junction

Psoriatic arthropathy – hands • • •

“Ray pattern” = involvement of all three joints is common IP joint ankylosis almost pathognomonic Extensive periostitis and hypertrophic enthesopathy

Psoriatic Arthropathy • •

“Mouse-ear” erosions DIP joints predilicted

Regular Notes Psoriasis – clinical • • • • • •

Dry, scaly erythematous patches o May bleed if scales removed Skin lesions common on extensor surfaces of arms/hands, in eyebrows and gluteal fold Nail changes seen in up to 80% of pat Hyperkeratosis, pitting and discoloration HLA B-27 factor in apporx. 75%, if SI joint are involved HLA B-27 factor I 30% of those with only small joint changes

Psoriatic arthropathy •

•

•

Patterns of involvement (Resnick) o Peripheral arthritis with DIP predilection o Pattern similar to rheumatoid o Asymmetrical oligoarthitis or monoarthritis o Arthritis mutilans o Sacroillitis More prominent features: o Asymmetrical o Joint swelling o Enthesopathy and periostitis o Bony ankylosis of interphalangeal joints Syndesmophytes o Asymmetrical o Coarse o Non-marginal o May be “comma-shaped” o Not as vertical as AS o Indistinguishable from Reactive arthritis o Often begin T–L junction

Psoriatic arthropathy – hands • • •

“Ray pattern” = involvement of all three joints is common IP joint ankylosis almost pathognomonic Extensive periostitis and hypertrophic enthesopathy

Psoriatic Arthropathy • • • •

“Mouse-ear” erosions DIP joints predilicted “Gull wing” is for EOA not psoriatic Most important is that psoriatic may fuse the joint but EOA will not

Psoriatic arthropathy SI • • • •

Bilateral and asymmetrical most common Wide, hazy joints – ankylosis in NOT common 30 – 50% involvement in pts with psoriatic arthropathy Strong assoc. of SI involvement in pts with nail disease

Psoriatic arthropathy •

Atlanto-axial instability may occur

•

Should always check Atlanto-dental interspace in any arthritis

Reactive arthritis • • •

Previously “Reiter’s Syndrome” o Reiter was not the first to describe the syndrome o Reiter is said to have been a Nazi sympathizer HLA factor on 80 – 90% pats o People with HLA B-27 factor are more at risk, but most HLA B-27 positive individuals Uncommon in black population and males predilected over females approx. 5:1

Reactive Arthritis • • • • • • • • • • • • • • •

Involvement of eyes, urinary tract and predilection for lower extremity involvement o Clinical mnemonic “Can’t see, Can’t pee, can’t dance with me” Conjunctivitis or iritis History of previous urinary tract or GI tract infection is common o May/not be SID o Shigella of GI tract reported Age of onset typically late teen to mid thirties Lower extremity predilection o Knee > Ankle > Forefoot > Calcaneus Most cases are self-limiting Est. 60 – 80% of pts eventually show x-ray changes o Only about 5% cases result in residual disability “Lover’s heels” Calcaneal osteophyte and/or periostitis Inflammatory erosions of small joints of feet may be seen Syndesmophyte formation in spine and sacroilitis SI joint fusion NOT common Erosive changes seen in up to 50% o Bone scan shows up to 70% pts have involvement Syndesmophyte formation is spine in approx. 15% Indistinguishable from psoriatic arthropathy o Thick, non-marginal and asymmetrical

RA •

• • • • • • •

Dx criteria include (must have at least 3 for diagnosis) o Morning stiffness >/= 1 hr. duration o 3 or more joints simultaneously involved  Joint swelling (fluid, not bony overgrowth)  MCP, PIP, MTP, ankle, wrist, knee, or elbow o Bilateral and symmetrical involvement o Rheumatoid modules on extensor surfaces or bony prominences o RA factor “+” o X-ray changes (erosions and demineralization) Should always asses transverse ligament before you adjust the C-spine (MRI not just x-ray) Periarticular osteopenia Marginal erosions Diffuse joint narrowing ST swelling Usually involves the ant. lat. side and the radial side more than the ulnar side Erosive joint disease in both upper and lower extremities – same pt

RA – advanced •

Misalignment of joints o Ulnar drift of MCs – ulnar deviation (AKA zigzag deformity)

o o

Called arthritis deformans (anytime any arthritis makes the hands dysfunctional) “Swan-neck” deformity

RA – hips • • • •

Uniform joint space loss Protrusio acetabuli may occur o “Otto’s pelvis” = bilateral protrusio acetabuli Secondary DJD may create confusing appearance Uniform joint space loss and erosions

RA •

• •

Spine o

Most common location in C-spine  Esp. C1/C2 o Always check atlantoaxial stability with flex/ext views o Pannus formation may stenose canal DO NOT MANIPULATE SPINE (any part) OF RA PT WITHOUT CHECKING FOR INSTABILITIES RA can involve the C-spine with no symptoms

Crystal Deposition Arthropathies • • •

Gout Calcium pyrophosphate Dihydrite Deposition (CPPD) (pseudogout) Hydroxyapatite Dihydrite Deposition disease (HADD) (chronic calcific tendonitis)

Gouty Arthritis •

•

• • •

Primary gout o Idiopathic o Uncommon o Usually diagnosed early teenage years Secondary gout o Renal disease o Hypertension o Myeloproliferative disease (multiple myeloma) o Inherent metabolic disorder o Hemolytic disease o Drug induced o Obesity Gout = “gutta” = to drop o Evil humors were thought to drop into the joint and cause pain “Podagra” Greek “pous” = foot + “agra” = to attack

Gouty arthritis – Clinical • • • • • • • • •

Age: typically 5th decade onset Sex: Males > females 20:1 Typically acute onset of monoarticular pain o Pt may think bitten by insect o D/dx infection! Get joint aspiration Usually exacerbation/remission pattern Very painful with associated swelling and redness 1st MTP joint involved classically Even though monoarticular pain it is a systemic disease and usually involves multiple joints Serum o Elevated serum uric acid may be seen in acute stage Joint fluid microscopy = major criterion of Dx o Joint aspiration yields needle shaped crystals o Polarized light microscopy shows negative bi-refringence of crystals

Gouty Arthritis – X-ray • • • • • • • • •

Radiographic manifestations not common o Most cases medically controlled o Repeated episodes necessary for x-ray changes to be seen Predilicts lower extremity Spine, hips, shoulders not commonly affected Joint spaces typically not compromised early Classic large erosion of joint margin or even away from joint edge Overhanging edge sign Sharp definition of erosion Periarticular soft tissue calcification may result from tophi (uric acid crystals deposited in soft tissue) By the time symptoms get bad enough to get x-ray findings they have had gout for years or decades

CPPD (Calcium Pyrophosphate Dihydrite Deposition) – many clinical patterns • • • • • •

“Pseudogout” affect approx. 10 –20% with acute joint pain/swelling Pseudo-rheumatoid pattern seen in approx. 2 – 3% Chronic arthritic pain with superimposed acute inflammatory episodes seen in 35 – 60% May mimic DJD in approx. 10 – 35% o Usually weight bearing joint Asymptomatic in significant number o Cartilage Ca++ seen in approx. 25% by 9th decade Neuropathic appearance in 1 – 2%

CPPD Clinical • • • •

•

Calcium pyrophosphate dihydrate deposition in articular cartilage or other periarticular tissue Age: Typically middle-aged to elderly Sex: men and women both affected Other conditions associated with CPPD include: o Hyperparathyroidism – renal osteodystrophy o Gout o DJD o Trauma o Ochronosis o Wilson’s Disease o Others … CPPD is almost certain to happen to pt on renal dialysis

CPPD – X-ray findings • •

• • • • • •

Deposition of calcium pyrophosphate dihydrate in hyaline cartilage of joint may result in cartilage calcification Favorite sites o Triangular fibrocartilage of wrist o Knee o 1st and 2nd MCP Involvement typically bilateral, but not always symmetrical Cloud-like Ca++ of synovium may occur as well Parallel calcifications along articular margins Note the “halo” of calcification that parallels the subchondral bone Prominent subchondral cyst formation common Unusual location suggestive o “Degenerative” change isolated to non-weight bearing joint such as radiocarpal joint or glenohumeral joint o Isolated Patellofemoral joint involvement also suggestive o May cause DJD of the 2nd and 3rd MCP joints

DOGPAW – joint diseases calcification of cartilage and surrounding tissue DJD - uncommon Ochronosis – rare Gout – uncommon Pseudogout – very common Acromegally – rare Wilson’s disease – rare Hydroxyapatite Dihydrite Deposition Disease (HADD) • • • • • • • •

Sometimes called “Calcific tendonitis” Most common in supraspinatous tendon Symptoms typically intermittent Calcification may appear/disappear on x-ray Calcification develops in the relatively avascular area of tendon near insertion – same place tears frequently occur Calcification typically more amorphous and “soft” than the nodular densities of synovial chondrometaplasia Dominant hand involvement more common, however may be bilateral Clumpy, amorphous area of ↑ density seen over proximal femur

Neuropathic arthropathy • •

•

“Charcot Joint” o Charcot described initially in association with neurosyphilis; other etiologies more common  5 – 10% of pts. With neurosyphilis develop neuropathic joint Other etiologies include: o Diabetes mellitus (est. 1 – 5% pts with DM) o Syringomyelia (est. 10 – 25% pts with syringomyelia) o Cushing’s syndrome or exogenous corticosteroids Clinical o Better described as “not as painful as anticipated” than “painless” o Loss of trophic nerve function and desensitization of joint to pain result in marked joint destruction

Hypertrophic type •

•

“D-words describe x-ray findings o ↑ density o Debris around joint o Destruction of bone o Disorganization o Dislocation Described as “DJD with a vengeance”

Atrophic type •

May look like a surgical resection o Sharply demarcated, smooth bone ends

Neuropathic arthropathy • • • • • •

Syringomyelia may cause neuropathic arthropathy of the upper extremities Paraplegic pt Dense sclerotic changes of hips and also in the lumbar spine Prominent heterotopic bone formation a the hips Relatively rapid progression may occur Diabetic pts are predisposed to lower extremity neuroarthropathy

Progressive systemic sclerosis – destroys the tip of the finger

Tumors Synovial chondral metaplasia • •

Primary type – unknown cause o Not as common as 2ndary Secondary type – caused by OA o Example bursa above patella calcifies looks like “marbles” above patella

Chordoma • • •

• •

•

•

Incidence: o 1% – 2% of spinal tumors Age and Sex o Male/Female 2:1; any age (when found almost all over 50 yrs old) Location o Two thirds occur in spine (low back/tailbone pain)  Sacrococcygeal area affected most often o One third at base of skull (Clivus) (headache/neck pain) Pathology o Originate from intraosseous notochordal remnants X-ray and CT o Lytic, destructive o One or more vertebral bodies and discs affected. o Soft tissue mass calcification 30% – 70% MRI o Lobulated, septated mass with fibrous capsule o Contents:  Hypo-intense T1 W1  Hype-intense T2 W2 Very slow growing and pts do not have major symptoms because of the slow growth the body is able to adapt

Pigment Villanodular Synovitis (PVS) • • • • • •

Predisposition for synovium to get very large with large villi Synovium gets so big that is cut off blood and infarcts and that’s is where it get the pigment in its name Synovium hardens and wears on the bone Adult Big joints – knee, hip, shoulder Best way to diagnosis is MR or synovial aspiration

Hypertrophic Pulmonary Osteo-arthropathy (HPOA) • •

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AKA: Pulmonary Osteodystrophy Will see triad o Clubbing of the fingers o Appendicular pain o Periostial elevation (periostitis) Large number of bronchiogenic carcinoma pts have is syndrome before cancer symptoms show up