Carpal bone fractures

CARPAL BONE FRACTURES

By:

Dr. Pavan

Moderator:

Dr. Vamsi

CARPAL BONESCarpal bones are arranged in two rows

From lateral to medial and when viewed from anteriorly

• PROXIMAL ROW 1. the boat-shaped scaphoid; 2. the lunate, which has a 'crescent shape'; 3. the three-sided triquetrum bone; 4. the pea-shaped pisiform• DISTAL ROW1. the irregular four-sided trapezium bone; 2. the four-sided trapezoid; 3. the capitate, which has a head; 4. the hamate, which has a hook

She Looks Too Pretty Try To Catch Her

CARPAL BONES IN 3D VIEW

SOME IMPORTANT CARPAL BONES

• Pisiform is a sesamoid bone in the tendon of flexor carpi

ulnaris and articulates with the anterior surface of the

Triquetrum.

• Scaphoid has a prominent tubercle on its lateral palmar

surface that is directed anteriorly.

• Trapezium articulates with the metacarpal bone of the thumb

and has a distinct tubercle on its palmar surface that projects

anteriorly.

• LARGEST of the carpal bones, the CAPITATE, articulates

with the base of the metacarpal III.

• Hamate, which is positioned just lateral and distal to the

pisiform, has a prominent hook (hook of hamate) on its

palmar surface that projects anteriorly.

• Ossification of the carpal bones occurs in a predictable sequence, starting with the capitate and ending with the pisiform.

• At birth, there is no calcification in the carpal bones. Although there is great individual variability, approximate ossification times are as follows :

capitate: 1-3 months hamate: 2-4 months triquetral: 2-3 years lunate: 2-4 years scaphoid: 4-6 years trapezium: 4-6 years trapezoid: 4-6 years pisiform: 8-12 years

CARPAL BONE OSSIFICATION CENTRES

• Excluding the pisiform, a handy way to remember the order of ossification is to start at the capitate then move in a counterclockwisedirection on the volar surface of the right carpus.

Ossification centres of the distal radius and ulna

distal radius: 1 year distal ulna: 5-6 years

• The carpal bones do not lie in a flat coronal plane; rather, they form an arch, whose base is directed anteriorly .

• The lateral side of this base is formed by the tubercles of the scaphoid and trapezium.

• The medial side is formed by the pisiform and the hook of hamate. The flexor retinaculum attaches to, and spans the distance between, the medial and lateral sides of the base to form the anterior wall of the so-called carpal tunnel. The sides and roof of the carpal tunnel are formed by the arch of the carpal bones.

LIGAMENTS OF WRIST

They are divided in to

1.Extrinsic ligaments

2.Intrinsic ligaments

Extrinsic ligaments :1. bridge carpal bones to the radius or

metacarpals

2. include volar and dorsal ligaments

Intrinsic ligaments:1. originate and insert on carpal bones

CHARACTERISTICS OF WRIST LIGAMENTS

– volar ligaments are secondary stabilizers of the scaphoid

– volar ligaments are stronger than dorsal ligaments

– dorsal ligaments converge on the triquetrum

EXTRINSIC LIGAMENTS

• Divided into

– Volar radiocarpal ligaments

– Volar ulnocarpal ligaments

– Dorsal ligaments

VOLAR RADIOCARPAL LIGAMENTS• Radial Collateral• Radioscaphocapitate

– at risk for injury with excessively large radial styloid– from radial styloid to capitate, creating a sling to

support the waist of the scaphoid

• Radioscapholunate– Ligament of Testut and Kuentz– only functions as neurovascular conduit– not a true ligament

• does not add mechanical strength

• Long Radiolunate– also called radiolunotriquetral or volar radiolunate

ligament– counteracts ulnar-distal translocation of the lunate– abnormal in Madelung's deformity

• Short radiolunate– stabilizes lunate

VOLAR ULNOCARPAL LIGAMENTS

• Volar ulnocarpalligaments

– ulnotriquetral

– ulnolunate

– ulnocapitate

DORSAL LIGAMENTS

• Radio Triquetral (RT)

• Dorsal Intercarpal (DIC)

• Radio Lunate (RL)

• Radio Scaphoid (RS)

• The distal portions of the radio and ulno capitateligaments do not attach to the head of the capitate, but form a support sling with centerof a double "V" shape covergence of ligaments

• Between these two rows of ligaments is a thinned area termed the Space of Poirier

SPACE OF PORIER

• Ligament free area in palmar aspect of capitolunate space is area of potential weakness

• This area expands when the wrist is dorsiflexedand disappears in palmar flexion.

• A rent develops during dorsal dislocations, and it is through this interval that the lunatedisplaces into the carpal canal.

TFCC(Triangular Fibrocartilage Complex)

• Major stabilizer of the ulnar carpus and distal radio ulnar joint.

• Absorbs 20% of the axial load across wrist joint

• Consists of– Ulnotriquetral ligament– Meniscal homologue– Articular disc– Dorsal radio ulnar ligament– Volar radio ulnar ligament– Ulnolunate ligament– Ulnar collateral ligament

INTRINSIC LIGAMENTSThe intra-articular intrinsic ligaments connect adjacent carpal bones.Proximal row

scapholunate ligamentlunotriquetral ligament

Distal rowtrapeziotrapezoid ligamenttrapeziocapitate ligamentcapitohamate ligament

Palmar midcarpalscaphotrapeziotrapezoidscaphocapitatetriquetralcapitatetriquetralhamate

VASCULAR SUPPLY OF CARPAL BONES

• The RADIAL,ULNAR and ANTERIORINTEROSSEOUS arteries combine to form a network of transverse arterial arches both dorsal and volar to the carpus.

• SCAPHOID BLOOD SUPPLY: primarily from radial artery,bothdorsally and volarly.

• Volar scaphoid branch supply distal 20%-30%

• branch entering dorsal ridge supplies proximal 70%-80%

• LUNATE BLOOD SUPPLY:recieves supply from both its dorsal and volar surfaces.

ARTERIAL SUPPLY OF DORSUM OF WRIST.

• R.radial artery• U.ulnar artery • 1.dorsal branch of

anterior interosseousartery

• 2.dorsal radiocarpal arch • 3.branch to dorsal ridge

of scaphoid• 4.dorsal intercarpal arch• 5.basal metacarpal arch• 6.medial branch of ulnar

artery.

ARTERIAL SUPPLY OF PALMAR ASPECT OF WRIST

• R, radial artery• U, ulnar artery • 1, palmar branch of anterior

interosseous artery • 2, palmar radiocarpal arch • 3, palmar intercarpal arch • 4, deep palmar arch• 5, superficial palmar arch • 6, radial recurrent artery • 7, ulnar recurrent artery • 8, medial branch of ulnar artery• 9, branch off ulnar artery

contributing to dorsal intercarpalarch.

ARTERIAL SUPPLY OF LATERAL ASPECT OF WRIST

• R, radial artery; • 1, superficial palmar artery; • 2, palmar radiocarpal arch; • 3, dorsal radiocarpal arch; • 4, branch to scaphoid tubercle and trapezium; • 5, artery to dorsal ridge of scaphoid; • 6, dorsal intercarpal arch; • 7, branch to lateral trapezium and thumb metacarpal.

KINEMATICS

• The global motion of the wrist is composed of flexion, extension, radioulnar deviation at the radiocarpal joint, and axial rotation around the distal radioulnar joint (DRUJ)

• The radiocarpal articulation acts as a universal joint allowing a small degree of intercarpal motion around the longitudinal axis related to the rotation of individual carpal bones.

• forearm accounts for about 140 degrees of rotation.• Radiocarpal joint motion is primarily flexion and extension of nearly

equal proportions (70 degrees) and radial and ulnar deviation of 20 degrees and 40 degrees, respectively.

• The scaphoid rests on the radioscaphocapitate ligament at its waist.using this ligament as axis it rotates from volar flexed perpendicular position to dorsiflexed longitudnal position.

• Wrist in radial deviation scaphoid flexes and in ulnar deviation scaphoid extends.

• Conjunct rotation of the entire proximal row occurs in flexion during radial deviation (upper left).

• The axes of the radius and carpal rows are collinear in neutral (middle left), and

• the proximal row extends with ulnar deviation (lower left).

• Angulatory excursions of the proximal and distal rows are essentially equal in amplitude and direction during extension (upper right) and flexion (lower right). This has been described as synchronous angulation.

WRIST BIOMECHANICS

• Biomechanic concepts that have been proposed for better understanding of functioning,movements and various types of forces acting.some of them are:

1. LINK CONCEPT

2. COLUMN CONCEPT

3. ROWS CONCEPT

4. TALEISNIK’S CONCEPT

5. LICHTMAN’S RING CONCEPT

LINK CONCEPT

• three links in a chain composed of radius, lunate and capitate– head of capitate acts as center of

rotation– proximal row (lunate) acts as a unit and

is an intercalated segment with no direct tendon attachments

– distal row functions as unit

• advantage– efficient motion (less motion at each

link)– strong volar ligaments enhance stability

• disadvantage– more links increases instability of the

chain– scaphoid bridges both carpal rows

• resting forces/radial deviation push the scaphoid into flexion and push the triquetrum into extension

• ulnar deviation pushes the scaphoidinto extension

COLUMN CONCEPT• lateral (mobile) column

– comprises scaphoid, trapezoid and trapezium

– scaphoid is center of motion and function is mobile

• central (flexion-extension) column

– comprises lunate, capitate and hamate

– luno-capitate articulation is center of motion

– motion is flexion/extension

• medial (rotation) column

– comprises triquetrum and distal carpal row

– motion is rotation

ROWS CONCEPT

• comprises proximal and distal rows

– scaphoid is a bridge between rows

• motion occurs within and between rows

TALEISNIK’S CONCEPT

• Taleisnik’s concept of central (flexion-extension) column involves entire distal row and lunate

• Scaphoid (S) is lateral (mobile) column, and

• Triquetrum (Tq) is rotary medial column.

LICHTMAN’S RING CONCEPT

• proximal and distal rows are semirigid posts stabilized by interosseous ligaments;

• Normal controlled mobility occurs at scaphotrapezialand triquetrohamate joints.

• Any break in ring, either bony or ligamentous(arrows), can produce dorsal intercalated segmental instability or volar intercalated segmental instability deformity.

PATHOMECHANICS

• The Radius, Lunate and Capitate have been described as a central link that is colinear in sagittal plane

• The Scaphoid serves as a connecting STRUT.Any flexion moment transmitted across the scaphoid is balanced by an extension at the triquetrum.

CARPAL INSTABILITY• Scaphoid instability by fracture or

scapholunate ligament disruption ,the lunate and triquetrumassume a position of excessive dorsiflexion(DISI-Dorsal Intercalated Segmental Instability) scapholunate angle becomes abnormally (high>70 degrees)

• When triquetrum is destabilized (disruption of the lunotriquetralligament complex) the opposite pattern (VISI-Volar Intercalated Segment Instability) is seen as the intercalated lunate segment volarflexes

LOAD-CARRYING STRUCTURES (WEBER AND CHAO)

. • These forces are related to fixed coordinate system

(XYZ) and to vector representation of applied load (P).

• Four ligamentous components (cb, ed, ih, kj) potentially transmit tensile loads when wrist is in strong dorsiflexion.

• Dorsal ligamentous structures eliminated from analysis because in dorsiflexion structures would be lax.

• Articular surface between radius and scaphoid and between radius and lunate potentially transmit compressive forces Ff and Fg.

• cb, radiocollateral ligament complex; • ed, radiocapitate ligament; • Ff, radioscaphoid contact force;• Fg, radiolunate contact force; • ih, radiolunate ligament; • kj, ulnar capsular ligament; • XYZ, cartesian coordinate system.

MECHANISM OF INJURY

• The most common mechanism of carpal injury is a fall onto the outstreched hand, resulting in an axial compressive force with wrist hyperextension. The volar ligaments are placed under tension with compression and shear forces applied dorsally, especially when the wrist is extended beyond its physiological limits.

• Excessive ulnar deviation and intercarpal supinationresult in predictable pattern of perilunate injury, progressing from the radial side of the carpus to the mid carpus and finally to the ulnar carpus.

Relative Incidence of Carpal Bone Fractures

• Scaphoid 68.2%

• Triquetrum 18.3%

• Trapezium 4.3%

• Lunate 3.9%

• Capitate 1.9%

• Hamate 1.7%

• Pisiform 1.3%

• Trapezoid 0.4%

CLINICAL EVALUATION

• HISTORY– age, – hand dominance, – occupation, – hobbies, – date of injury or onset of symptoms, – correlation of symptoms with activities– modifying factors

• LOCAL EXAMINATION– Well localised tenderness– Deformity– Mechanical symptoms, such as clicking, popping, snapping, and

grating– Provocative test

RADIOGRAPHIC TECHNIQUES

Various radiographic techniques useful in evaluating a painful wrist include

routine radiographic series consisting of four views 1. posteroanterior, 2. lateral, 3. oblique, and 4. ulnardeviated posteroanterior scaphoid view

spot views of the carpal bones for detail (carpal tunnel view)

fluoroscopic spot views of the wrist;

GILULA'S LINES. A. PA views show three smooth Gilula arcs in a normal wrist. These arcs outline

proximal and distal surfaces of the proximal carpal row and the proximal cortical margins of capitate and hamate.

B. Arc I is broken, which indicates an abnormal lunotriquetral joint due to a perilunate dislocation. Additional findings are the cortical ring sign produced by the cortical outline of the distal pole of the scaphoid and a trapezoidal shape of the lunate.

Carpal tunnel view shows avulsion fracture of hamate hook (arrow) and trapezium (arrowheads).

fluoroscopic spot views of the wristA, Posteroanterior view of capitate shows no definite abnormality. B, On angled view, cystic defect with fracture is seen in capitate waist (arrows).

series of views for instability 1. anteroposterior clenched fist; 2. posteroanterior in neutral, radial, and ulnar

deviation; 3. lateral in neutral and full flexion and

extension; 4. semipronated oblique 30 degrees from the

posteroanterior5. semisupinated oblique 30 degrees from the

lateral

Diagnostic ultrasound Cine or Video Fluoroscopy Bone Scanning Arthrography of the wrist (triple injection

when indicated) CT MRI.

OTHER DIAGNOSTIC TECHNIQUES

1. differential local anesthetic injection,

2. wrist arthroscopy, and

3. various other operative procedures.

Positioning of patientA, Standard radiocarpal portals. B, Standard midcarpal portals.

SCAPHOID FRACTURES

SCAPHOID FRACTURES• irregularly shaped tubular bone, twisted and bent into an

S-shape

• resembles a deformed peanut or a boat (from the Greek word for boat, skaphos).

• more than 80% of its surface being covered by articularcartilage

• The scaphoid receives most of its blood supply from two major vascular pedicles .

• One enters the scaphoid tubercle and supplies its distal 20% to 30% and the other arises from the dorsal scaphoidbranch of the radial artery .

• The dorsal ridge vessels enter through numerous small foramina along the spiral groove and dorsal ridge. This source accounts for about 80% of the blood supply.

• unusual retrograde vascular supply, the scaphoid has a high risk of nonunion and Osteonecrosis after fracture.

• Temporary interruption of the blood supply to the proximal fragment is virtually certain with proximal pole fractures.

EPIDEMIOLOGY

incidence

• accounts for up to 15% of acute wrist injuries

location

• incidence of fracture by locationo waist -65%

o proximal third - 25%

o distal third - 10%

distal pole is most common location in kids due to ossification sequence

CLINICAL EVALUATION OF SCAPHOID FRACTURE

• complain of wrist pain after a fall on the outstretched hand• Minimal or gross swelling • snuffbox tenderness• scaphoid tubercle tenderness• Palpable deformity distal to radial styloid• pain with longitudinal axial compression/tension• Pain with dorsiflexion, radial deviation • pain with resisted pronation• PROVOCATIVE TESTS

THE SCAPHOID SHIFT TEST: Reproduction of pain with dorsal-volar shifting of scaphoid.

THE WATSON TEST: Painful dorsal scaphoid displacement as the wrist is moved from ulnar to radial deviation with palmar pressure on the tuberosity.

PATHOANATOMY

– most common mechanism of injury is axial load across hyper-extended and radially deviated wrist

• common in contact sports

– transverse fracture patterns are considered more stable than vertical or oblique oriented fractures

SCAPHOID FRACTURE IMAGING

• Radiographs– Recommended views

• AP and lateral• scaphoid view

– 30 degree wrist extension, 20 degree ulnar deviation

• 45° pronation view

– Findings• if radiographs are

negative and there is a high clinical suspicion– should repeat

radiographs in 14-21 days

•The four scaphoid views (PA, true lateral, radial oblique, ulnar oblique) detect most of carpal fractures. •A fisted PA view can be helpful in detecting scaphoid fractures.

UNSTABLE FRACTURE

• Greater than 1 mm stepoff

• Lunocapitateangulation > 15 degrees (lateral)

• Scapholunateangulation > 45 degrees (lateral)

• Bone scan– effective to

diagnose occult fractures at 72 hours• specificity of

98%, and sensitivity of 100%, PPV 85% to 93% when done at 72 hours

.

• MRI– most

sensitive method to diagnose of occult fractures within 24 hours

– allows immediate identification of fractures and ligamentous injuries in addition to assessment of vascular status of bone (vascularity of proximal pole)

• CT scan with 1mm cuts– less effective than

bone scan and MRI to diagnose occult fracture

– can be used to evaluate location of fracture, size of fragments, extent of collapse, andprogression of nonunion or union after surgery

The MRI scan demonstrates a clear fracture line of the scaphoid (proximal pole). B. It is difficult to identify the proximal fracture by native x-rays.

• MRI is useful for diagnosis of “occult” scaphoid fractures (A) and for evaluation of vascularity of fractured scaphoid(B).

CLASSIFICATION OF SCAPHOID FRACTURES

HERBERT AND FISHER'S CLASSIFICATION OF FRACTURES OF THE SCAPHOID

NONDISPLACED, STABLE SCAPHOID FRACTURES

NONOPERATIVE THUMB SPICA CAST IMMOBILIZATION

• INDICATIONS– stable nondisplaced fracture (majority of fractures)– Tuberosity fracture– Patient with injury and positive examination findings but normal x-rays, immobilize

for 1-2 weeks.

• TECHNIQUE– start immobilization early (nonunion rates increase with delayed immobilization of

> 4 weeks after injury).– long arm spica vs short arm casting is controversial

» with no consensus– duration of casting depends on location of fracture

» distal-third for 6-8 weeks» mid-third for 8-12 weeks» proximal third for 12-24 weeks» athletes should not return to play until imaging shows a healed fracture

– may opt to augment with pulsed electomagnetic field (studies show beneficial in delayed union)

• OUTCOMES– scaphoid fractures with <1mm displacement have union rate of 90%

THUMB SPICA CAST IMMOBILIZATION

• Forearm cast from just below the elbow proximally to the base of the thumbnail and the proximal palmar crease distally (thumb spica) with the wrist in slight Radial deviation and in Dorsiflexion. The thumb is maintained in a functional position, and the fingers are free to move from the metacarpophalangealjoints distally.

• Using nonoperative casting techniques, the expected rate of union is 90% to 95% within 10 to 12 weeks.

• During this time, the fracture is observed radiographically for healing.

• If collapse or angulation of the fractured fragments occurs, surgical treatment usually is required.

• Surgery may be considered if new healing activity is not evident and if union is not apparent after a trial of cast immobilization for about 20 weeks.

DISPLACED, UNSTABLE SCAPHOID FRACTURES

• Displaced,unstable fracture in which the fragments are offset more than 1 mm in the anteroposterior or oblique view, or lunocapitate angulation is > 15 degrees, or the scapholunate angulation is > 45 degrees in the lateral view (range 30 to 60 degrees).

OPERATIVE– ORIF vs percutaneous screw fixation

• INDICATIONS

– in unstable fractures as shown by

» proximal pole fractures

» displacement > 1 mm

» 15° scaphoid HUMPBACK DEFORMITY

» radiolunate angle > 15° (DISI)

» intrascaphoid angle of > 35°

» scaphoid fractures associated with perilunate dislocation

» comminuted fractures

» unstable vertical or oblique fractures

– in non-displaced waist fractures

» to allow decreased time to union, faster return to work/sport, similar total costs compared to casting

• OUTCOMES

– union rates of 90-95% with operative treatment of scaphoid fractures

» CT scan is helpful for evaluation of union

HUMPBACK DEFORMITY

• Humpback deformity of the scaphoid results from angulationof the proximal and distal parts of a scaphoid in the setting of scaphoid fracture through the waist .

• It can result in progressive collapse of the scaphoid with non-union and destabilisation of the wrist.

• Associated with a Dorsal Intercalated Segment Instability(DISI).

• Managed operatively with internal fixation + / - bone grafting.

TECHNIQUE• ORIF vs percutaneous screw fixation

– Approach• Dorsal approach

– indicated in proximal pole fractures– care must be taken to preserve the blood supply when entering the dorsal

ridge by limiting exposure to the proximal half of the scaphoid– percutaneous has higher risk of unrecognized screw penetration of

subchondral bone

• Volar approach– indicated in waist and distal pole fractures and fractures with humpback

flexion deformities– allows exposure of the entire scaphoid– uses the interval between the FCR and the radial artery

• Arthroscopic assisted approach– has also been described

– Fixation• rigidity is optimized by long screw placed down the central axis of the

scaphoid

– Radial styloidectomy• should be performed if there is evidence of impaction osteoarthritis

between radial styloid and scaphoid

OPEN REDUCTION AND INTERNAL FIXATION OF ACUTE DISPLACED FRACTURES OF THE SCAPHOID—VOLAR APPROACH

OPEN REDUCTION AND INTERNAL FIXATION OF ACUTE DISPLACED FRACTURES OF THE SCAPHOID—DORSAL APPROACH

EXPOSURE AND INTERNAL FIXATION OF SCAPHOID FRACTURES THROUGH A DORSOLATERAL APPROACH

• A: Skin incision.• B: Exposure of the

dorsal radiocarpal joint capsule after isolating and protecting the superficial radial nerve and radial artery.

• C: Scaphoid exposure through dorsal radiocarpalcapsulotomy.

• D:Reduction of scaphoid fracture.

• E:Use of double-guidewire technique for placement of screw and counter-rotation. The second guidewireis removed after placement of the screw.

PERCUTANEOUS SCAPHOID FIXATION THROUGH A VOLAR APPROACH.

• With longitudinal traction and ulnar deviation, the guidewire is inserted through a 5-mm incision directly over the scaphoidtubercle.

PERCUTANEOUS FIXATION OF SCAPHOID FRACTURES

A, Central axis of scaphoid is located on posteroanteriorview. B, Wrist is pronated until scaphoid poles are aligned.C, Wrist is flexed until scaphoid has “ring” appearance on fluoroscopy.

Guidewire in central axis of scaphoid for placement of screw.

COMPLICATIONS OF SCAPHOID FRACTURES

• Osteoarthritis

• Delayed union

• Malunion

• Nonunion

• Nonunion SNAC wrist (scaphoid nonunionadvanced collapse)

• Osteonecrosis (PREISER'S DISEASE )

Algorithm for treatment of scaphoidnonunion developed by Knoll and

Trumble

SCAPHOID NONUNION AND SCAPHOID NONUNION ADVANCED COLLAPSE (SNAC WRIST)

• Radiographic findings of arthritis usually seen with scaphoid nonunion include radioscaphoid narrowing, capitolunate narrowing, cyst formation, and pronounced Dorsal Intercalated Segment Instability.

• This is the so-called SCAPHOID NONUNION ADVANCED COLLAPSE PATTERN.

• The following operations can be useful for nonunions of the scaphoid:

(1) Radial Styloidectomy.

(2) Excision of the proximal fragment, the distal fragment, and, occasionally, the entire scaphoid.

(3) Proximal row Carpectomy.

(4) Traditional Bone Grafting.

(5) Vascularized Bone Grafting.

(6) Partial or Total Arthrodesis of the wrist.

PROXIMAL ROW CARPECTOMY

Arthroscopic proximal row carpectomy

Arthroscopic proximal row carpectomy .A, Initial removal of distal ulnar pole of scaphoid. B, Entire proximal row has been excised. C, After release of traction.

BONE GRAFT TECHNIQUES

STARK ET AL. GRAFTING TECHNIQUE

VASCULAR BONE GRAFT FROM RADIUS

– VASCULAR BONE GRAFT FROM RADIUS• gaining popularity and a

good option for proximal pole fractures with osteonecrosis confirmed by MRI

• 1-2 intercompartmentalsupraretinacularartery (branch of radial artery) is harvested to provide vascularized graft from dorsal aspect of distal radius

PREISER'S DISEASE (SCAPHOID AVN)

• Osteonecrosis of the scaphoid can occur as a late complication of scaphoid fractures, especially those involving the proximal pole.

• Epidemiology– Rare condition– Mostly idiopathic– Average Age of onset is 45 years

• Operative treatment options: microfracture drilling, revascularization procedure, or

allograft replacement proximal row carpectomy or scaphoid excision with four

corner fusion

TRIQUETRAL FRACTURES

TRIQUETRUM FRACTURES

• 2 nd most common carpal bone fracture after scaphoid• Mode of injury:

wrist in extension and ulnar deviation • Clinical evaluation:

tenderness on palpation on the dorsolunar aspect of the wrist directly dorsal to pisiform,painful wrist motion

• Radiological evaluation:1.tranverse fracture of body identified on PA view2.Dorsal triquetrum visualized by oblique ,pronated lateral view

• Treatment:nondisplaced fractures of the body or dorsal chip fractures may be treated in short arm cast or splint for 6 wks.displaced with ORIF.

TRAPEZIAL FRACTURES

TRAPEZIUM FRACTURES

• 3-5% of carpal bone fractures

• 60% unsatisfactory due to secondary degenerative changes

• Ridge avulsion or vertical fracture of body

MODE OF INJURY OF TRAPEZIAL FRACTURES

• Axial loading of adducted thumb

• Driving base of 1st metacarpal into articularsurface of trapezium

• Avulsion fractures- forceful deviation,traction,rotation of thumb

• Direct trauma to palmar arch- avulsion of trapezialridge by transvers carpal ligament

CLINICAL EVALUATION OF TRAPEZIAL FRACTURES

• Tenderness of radial wrist

• Painful range of motion of 1st carpometacarpaljoint

RADIOGRPHIC EVALUATION

• Along with standard PA and Lateral views

• Robert view

• True PA of 1st CMC joint and trapezium with hand in maximum pronation

• Carpal tunnel view-dorsal ridge visualization

TREATMENT OF TRAPEZIUM

• Non displaced:

– Thumb spica splinting for 6 weeks

• Displaced, Comminuted, CarpometacarpalArticulation involvement

– ORIF +\- Bone Grafting

LUNATE FRACTURES

LUNATE FRACTURES

• 4TH most fractured

• CARPAL KEYSTONE– lunate sits like a keystone in the proximal carpal row in the well-protected

concavity of the lunate fossa of the radius, anchored on either side by the interosseous ligaments to the scaphoid and triquetrum with which it articulates. Distally, the convex capitate head fits into the concavity of the lunate

BLOOD SUPPLY TO LUNATE

• vascular supply of the lunate is primarily through the proximal carpal arcade both dorsally and palmarly. However, the literature suggests that 7% to 26% of lunates may have a single volar or dorsal blood supply and are therefore vulnerable to Osteonecrosis because of disruption of extraosseous blood supply

MECHANISM OF INJURY

• Outstreched hand

• Wrist in hyperextension

• Strenous push with wrist in extension

CLINICAL EVALUATION FOR LUNATE FRACTURES

• Tenderness on dorsal wrist overlying the distal radius and lunate

• Painful ROM

RADIOGRAPHIC EVALUATION OF LUNATE

• PA & Lateral views inadequate

• Oblique views may be helpful

• CT best demonstrates fractures

• MRI increasingly used for vascular changes associated with injury and healing.

– test of choice for evaluation of Kienbock Disease.

ACUTE LUNATE FRACTURE CLASSIFICATION

• acute fractures of the lunate are classified into five groups:1. Frontal fractures of the palmar pole with

involvement of the palmar nutrient arteries.

2. Osteochondral fractures of the proximal articularsurface without substantial damage to the nutrient vessels.

3. Frontal fractures of the dorsal pole.

4. Transverse fractures of the body.

5. Transarticular frontal fractures of the body of the lunate.

TREATMENT OF LUNATE FRACTURES

• Non displaced:Most fractures of the lunate can be treated by cast

immobilization for 4 weeks.

• Displaced :displaced or angulated fractures treated surgically for adequate apposition for vascular anastomosis.

• Fractures with more than 1 mm offset and avulsion fractures usually require open reduction.

• Internal fixation techniques vary depending on the requirements of the individual situation and may include Kirschner wires,small cannulated screws, and suture anchors

COMPLICATIONS OF LUNATE FRACTURES

• The lunates believed to be most at risk for osteonecrosis are those with a single vessel or one surface exposed to the blood supply, representing about 20% of lunates.

• Kienböck disease is a painful disorder of the wrist of IDIOPATHIC cause in which radiographs eventually show osteonecrosis of the carpal lunate.

KIENBOCK'S DISEASE

• Avascular necrosis of the luntate leading to abnormal carpal motion

• Epidemiology

– incidence

• most common in males between 20-40 years old

– risk factors

• history of trauma

CLINICAL PRESENTATION of KIENBOCK’S DIESEASE

• Symptoms– dorsal wrist pain

• usually activity related• more often in dominant hand

• Physical exam– inspection and palpation

• +/- wrist swelling• often tender over radiocarpal joint

– range of motion• decreased flexion/extension arc• decreased grip strength

• Prognosis

– potentially debilitating condition if unrecognized and untreated

• Blood supply to lunate

– 3 variations

• Y-pattern

• X-pattern

• I-pattern– 31% of patients

– postulated to be at the highest risk for avascular necrosis

PATHOPHYSIOLOGY OF KIENBOCK’S DIESEASE

• thought to be caused by multiple factors– biomechanical factors

• ulnar negative variance– leads to increased radial-lunate

contact stress

• repetitive trauma

– anatomic factors• geometry of lunate

• vascular supply to lunate– patterns of arterial blood supply

have differential incidences of AVN

– disruption of venous outflow

IMAGING OF KIENBOCK’S

• Radiographs– recommended views

• AP, lateral, oblique views of wrist

• CT– most useful once lunate collapse has already occurred– best for showing

• extent of necrosis• trabecular destruction• lunate geometry

• MRI– best for diagnosing early disease– findings

• decreased T1 signal intensity• reduced vascularity of lunate

LICHTMAN CLASSIFICATION AND TREATMENT RECOMMENDATIONS

CAPITATE FRACTURES

CAPITATE FRACTURES

• Isolated capitate fractures uncommon

• Associated with Greater Arc Injury Pattern (TransscaphoidTranscapitate PerilunateFracture-Dislocation )

• Naviculocapitate syndrome variation in which capitateand scaphoid fractured without associated dislocation

• Mechanism– Direct trauma or crushing

injuries associated with carpal or metacarpals

CAPITATE FRACTURES

• CLINICAL EVALUATION:

– Point tenderness

– Painful dorsiflexion of wrist as capitate impinges on dorsal rim of radius

• RADIOGRAPHIC EVALUATION

– Standard scaphoid views

– CT scan

CAPITATE FRACTURES

• Treatment

– CRIF or ORIF with Kirschner wires or Lag screws to restore normal anatomy to reduce risk of Osteonecrosis

• Complications

– Midcarpal arthritis

– osteonecrosis

HAMATE FRACTURES

HAMATE FRACTURES

• May be fractured through– Through Hook(most common)– Through Hamulus– Through Distal articular surface– Through Other articular surface

• Present with history of blunt trauma to palm of hand– often seen in racquet sports

hockeygolf (miss ball and hit ground) tennis

• Must distinguish from bipartite hamate (will have smooth cortical surfaces)

CLINICAL EVALUATION OF HAMATE FRACTURES

• Symptoms– hypothenar pain

– decreased grip strength

– paresthesias in ring and small finger• Ulnar & Median Neuropathy

– ulnar nerve compression in Guyon's canal

– occasionally in thumb, index, middle and ring finger due to median nerve compression in carpal tunnel

– motor weakness of intrinsics (ulnar nerve compression in Guyon's canal)

RADIOGRAPHIC EVALUATION OF HAMATE FRACTURES

• Radiographs

– recommended views

difficult to visualize fracture on AP

best seen on a carpal tunnel view

• CT

– best study to make diagnosis

TREATMENT OF HAMATE FRACTURES

• Nonoperative– immobilization in a short arm splint/cast for 6 weeks

• Operative– excision of hamate fracture fragment

• indications– chronic hook of hamate fractures

– ORIF• With k-wires or screws

• Complications– Symptomatic non union– Ulnar and median neuropathy– Rupture of the flexor tendons to the small finger

PISIFORM FRACTURES

PISIFORM FRACTURES

• The Pisiform is a sesamoid bone located within the Flexor Carpi Ulnaris tendon– origin for Abductor Digiti Minimi

• Epidemiology– incidence

• 1%-3% of carpal fractures

• Mechanism– Fall on outstretched hand– Fall on Dorsiflexed hand– Direct blow to volar aspect of wrist

• Associated conditions– 50% of pisiform fractures occur with distal radius, hamate, or

triquetral fractures

PISIFORM FRACTURES

• CLINICAL EVALUATION– Tenderness on volar aspect,ulnar side of wrist. With

painful passive extension of wrist as flexor carpiulnaris is tensed.

• RADIOGRAPHIC EVALUATION– Radiographs

• recommended views– lateral view of wrist with forearm supination of 20-45 degrees – utilizing the carpal tunnel view of 20 degree supination oblique

view demonstrating an oblique projection of the wrist in radial deviation and semisupination.

– CT

TREATMENT OF PISIFORM FRACTURES

• NONOPERATIVE– IMMOBILIZATION

• indications– first line of treatment– short arm cast with 30 degrees of wrist flexion and ulnar deviation

for 6 weeks• outcomes

– patients that sustain fracture of pisiform most often go on to heal without posttraumatic osteoarthritis

• OPERATIVE– PISIFORMECTOMY

• indications– painful nonunion

• outcomes– studies show a pisiformectomy is a reliable way to relieve this pain

and does not impair wrist function

TRAPEZOIDAL FRACTURES

TRAPEZOID FRACTURES

• Rare

• Axial load and crush injuries associated with other carpal fractures

• Clinical evaluation

– Tenderness and painful range of motion proximal to base of 2nd metacarpal

TRAPEZOID FRACTURES

• Radiographic evaluation– Radiographs

PA views compared with contralteral, uninjured wrist

Oblique views

– CT scan

• Treatment– Short arm Splint/cast for 6 weeks in undisplaced fractures

– ORIF with K-wires with restoration of articular congruity

• Complication– 2nd CMC articulation joint congruity of not restores leads to

post traumatic osteoarthritis

PUTMAN AND MEYER TABULATED THE TYPES OF FRACTURES OF CARPAL BONES OTHER THAN THE SCAPHIOD

REFERENCES

• CAMPBELL’S OPERATIVE ORTHOPAEDICS, TWELFTH EDITION.

• Rockwood & Green's Fractures in Adults, 6th Edition.

• GRAY’S Anatomy for Students.

• World Wide Net

THANK YOU