3. Introduction
6% to 7% of all carpal injuries
18% of hand fractures
The scaphoid (79%) and triquetrum (14%) are the most frequently
fractured
Isolated fractures of any of the remaining carpal bones is 1%
3
5. Incidence and Cause
60% to 70% of all carpal fractures
Majority of injuries are low-energy injuries
82% in males, average age of 25
Annual incidence - 43 per 100,000 people
5
6. Pertinent anatomy
Divided into three parts: the distal pole,
waist, and the proximal pole
The tubercle
80% is covered with articular cartilage
Blood supply
6
7. Biomechanics of Scaphoid Fractures
Hyperextension past 95 degrees is the usual position of injury
(In extreme dorsiflexion and ulnar deviation)
Axial loading
Hyperflexion
7
8. Biomechanics Con’t…
15% to 80% at the waist
10% to 15% at the proximal pole
5% to 10% at the distal pole including the tuberosity
Scaphoid fractures heal by intramembranous ossification
Loading before union – “humpback” deformity
8
9. Implications of Nonunion
Nonunion occurs in 10% to 15%
The risk of nonunion increases with:
• Delay of treatment for more than 4 weeks
• Proximal pole fractures
• Fracture displacement greater than 1 mm
• Osteonecrosis
• Associated carpal instability
* SNAC
9
10. Clinical Presentation
Pain on the radial side of the wrist +/- swelling
A history of trauma
Limited range of motion and pain
10
11. Physical Examination
Swelling and bruising in the radial aspect of the wrist
Limited range of motion
“Snuffbox tenderness”
11
19. Clinically suspected scaphoid fractures
Short-arm thumb spica cast immobilization
Follow-up radiographs and clinical examination without the
cast at 10 to 14 days
Negative follow-up radiographs - MRI
19
20. Stable Acute Fractures
Distal Pole Fractures
• Treated nonoperatively
• Have a high rate of union after 6 to
8 weeks
20
21. Incomplete Fracture Through the Waist, Negative Radiographs,
Positive MRI Studies
• Less strict immobilization
• Short-arm thumb spica cast / splint
• Percutaneous fixation
21
26. Dorsal Approach
Fixation gets down to the true axis
Ease of access to place a screw closer to
the central axis
Risk of disrupting dorsal blood supply
Risk of injury of the extensor tendons
Might displace an unstable fracture
Palmar Approach
Not possible to place the screw down the
true axis of the bone
Poor exposure of the proximal pole
No tendons in the path of the approach
Preserves the blood supply
Help to reduce the fracture
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28. Transscaphoid Perilunate Fracture-Dislocations
Fracture of the scaphoid with dorsal dislocation of the carpus
relative to the lunate
5% of wrist fractures
Twice as common as pure ligamentous dislocations
Usually due to a high-energy impact
Mechanism - forceful wrist extension, ulnar deviation, and
intercarpal supination
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29. Con’t…
Classified as greater and lesser arc injuries
Bone or ligament failure starts radially and
propagating ulnarly
Variations - fractures of the capitate,
triquetrum, radial styloid, and ulnar styloid
29
30. Con’t…
Scaphocapitate syndrome
• Fracture of scaphoid and capitate
• Capitate may rotate
• CT scan*
• ORIF through a dorsal approach
30
31. Radiocarpal And Intercarpal Dislocation
Missed in 25% of the patients
Recognition, accurate reduction, and stable internal fixation
Scapholunate ligament (SLIL) tear
Lunotriquetral ligament injury
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34. Fractures of the Triquetrum
3% to 5% of all carpal fractures
Three primary patterns:
• Dorsal cortical fracture
• Triquetral body fracture
• Palmar cortical fracture
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35. Dorsal Cortical Fracture
Most common
Mechanisms of injury - avulsion, shear
forces, or impaction
Extreme palmar flexion with radial
deviation – dorsal avulsion
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36. Body Fracture
Require a high amount of injury to the wrist
Perilunate fracture dislocations are seen in
12% to 25%
Divided into five categories
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37. Palmar Cortical Fracture
Represent an avulsion of the palmar ulnar triquetral
ligament and the LTIO ligament
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38. Clinical and Radiographic Features
Point tenderness to palpation directly over the triquetrum
Identified with AP, lateral, and 45-degree pronated oblique
radiographs of the wrist
CT scan
38
39. Treatment
Dorsal cortical fractures treated non-operatively with
immobilization for 4 to 6 weeks
Isolated body fractures – casting
Displaced triquetral body fractures - ORIF
Associated with a perilunate fracture-dislocation – pinning the
joint
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40. Fractures of the Trapezium
1% to 5% of all carpal bone fractures
Usually associated with fractures of other bones
Involve the body or the ridge
A vertical intraarticular fracture pattern is the most
common
40
42. Imaging
PA and lateral radiographic wrist views
Pronated AP view
The Bett view
CT scan will best define the fracture
42
43. Treatment
Nondisplaced - short-arm thumb spica cast for 4 to 6 weeks
Displaced fractures – ORIF
Best addressed through a volar approach
By compression screws or Kirschner wires
43
44. Fractures of the Capitate
1% to 2% of all carpal fractures
4 patterns of fracture
• Transverse fracture of the body
• Transverse fracture of the proximal
pole
• Coronal oblique fracture
• Parasagittal fracture pattern
44
45. Mechanism of Injury
High-energy fall with the wrist hyperextended
Axial load down the third metacarpal or
Direct blow
45
47. Treatment
ORIF
• Displaced fractures of the capitate
• Delayed diagnosis of nondisplaced capitate fractures
• Transscaphoid, transcapitate perilunate fracture-dislocations
47
48. Fractures of the Hamate
2% of all carpal fractures
Involve the body, the dorsal rim & the hook
Frequently associated with fracture -
dislocation/subluxation of 4th & 5th CMCJ
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49. Fractures of the Hook of the Hamate
More common in athletes
Present with pain and weakness of grip
X ray - A carpal tunnel view and a 30° palmar tilted lateral
projection
49
50. Treatment
Acute nondisplaced fractures of the hook heal with casting
and immobilization
Early diagnosis - ORIF with a screw
Late with non union - subperiostul excision of the hook
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51. Fractures of the Pisiform
2% of all fractures of the carpal bones
Result from a direct blow
Tenderness over the base of the hypothenar
eminence
Carpal tunnel or Reverse oblique view
Cast immobilization for 4 to 6 weeks
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52. Fractures of the Trapezoid
<1% of all carpal fractures
Mechanism - High-energy trauma
• Axial load of index MC
• Extreme index MC palmar flexion
Non displaced – nonoperative
Displaced fractures – ORIF
* Excision is contraindicated
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53. Fractures of the Lunate
1% of all carpal fractures
In association with Kienbock disease
Tenderness immediately distal to the lister tubercle
Cast immobilization for 4 to 6 weeks for undisplaced
and chip fractures
ORIF for large displaced fractures
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Carpal fractures are often associated with fractures of other carpal bones, fracture of the distal radius, and ligamentous instability of the carpus
These fractures are a diagnostic challenge because of their infrequency and the difficulty in detecting them on initial conventional radiographs.
Missed carpal fractures have a high risk of developing degenerative arthritis resulting in a chronically painful wrist
is the “keystone” of the carpus
the scaphoid links the carpus together.
Pathologic conditions of the scaphoid can affect the entire wrist.
most commonly fractured carpal bone
are second in frequency of wrist fractures only to distal radius fractures.
The majority of injuries are low-energy injuries, either from a sporting event (59%) or from a fall onto an outstretched wrist (35%);
The remainder result from high-energy trauma such as a fall from a height or a motor vehicle injury.
Howe documented that 82% of the scaphoid fractures in Norway occur in males, with an average age of 25 years (range, 11 to 79 years)
The scaphoid is boat shaped (scaphos [Greek] = skiff) and concave in both the ulnar and palmar directions
The tubercle is the distal and palmar protuberance of the scaphoid
Approximately 70% to 80% of the blood supply of the scaphoid arises from dorsal branches of the radial artery that enter at the level of the waist.
The remaining 20% to 30% of the blood supply is via palmar braches of the radial artery that enter via the distal tubercle
The proximal pole of the scaphoid is vascularized by retrograde flow by intraosseous vessels and explains the slower union and increased tendency for proximal pole fractures to go into avascular necrosis (AVN)
Fractures through scaphoid waist can compromise blood supply to the proximal pole: This leads to avascular necrosis (AVN) of proximal fragment in as many as one-third of cases
The scaphoid links the proximal and distal carpal rows. It assumes a flexed foreshortened posture in radial deviation and wrist flexion and an extended and elongated posture on ulnar deviation and wrist extension.
A fall on the outstretched hand causes the proximal aspect of the scaphoid to impact on the dorsal rim of the distal radius resulting in palmar tensile and dorsal compressive forces causing a fracture through the scaphoid waist
Carpal dislocations and scapholunate ligament tears were reproduced with wrist extension and ulnar deviation, combined with intercarpal supination
Another mechanism of injury is a pure compressive force (axial loading) like in an automobile accident
Fractures tend to occur at the waist partly because the RSC (radioscaphocapitate) ligament acts as a fulcrum over which the scaphoid waist fractures
The displacement of a scaphoid fracture depends on the direction and degree of force and the plane of the fracture
There is no fracture callus to provide initial stability.
If the wrist is loaded before union occurs, it can lead to progressive flexion and pronation of the distal scaphoid, especially in unstable or displaced fractures.
The distal scaphoid fragment has a tendency to flex and the proximal fragment extends by virtue of its attachment to the lunate. This combined with the resorption of bone on the volar aspect will lead to a "humpback" or flexion deformity of the scaphoid
As with any fracture, the potential for healing relies on the fracture’s location, vascularity, and stability
For nondisplaced waist fractures treated with casting, nonunion rates are 5% to 12%.
Nonunion rates for displaced scaphoid fractures treated nonoperatively are higher, reaching 50%
Associated carpal instability (DISI = dorsal intercalated segmental instability with a scapholunate angle > 60 degrees and a capitolunate angle > 15 degrees) secondary to humpback (flexed with intrascaphoid angle > 45 degrees; the normal intrascaphoid angle is 24 degrees) scaphoid positioning
Untreated scaphoid nonunion will predictably progress to arthritic change, in what has been termed scaphoid nonunion advanced collapse (SNAC). Which will eventually lead to pancarpal arthritis
pain on moving the wrist and the thumb
There may be swelling on the radial side
There is usually a history of trauma, such as falling on an outstretched hand, collision of the wrist against a person or heavy obstacle, or possibly a direct blow against an object
Limited range of motion and pain when applying extended wrist loading or positioning the wrist in extreme positions of flexion or extension
Patients presenting subacutely may complain of vague ache in the wrist with loss of motion or strength.
In diagnosing scaphoid fracture, physical examination is sensitive but its specificity is low, ranging from 74% to 80%
“Snuffbox tenderness” has become synonymous with scaphoid fracture, but this applies predominantly to waist fractures, which represent 70% of scaphoid fractures
The full physical examination of the scaphoid bone should include all of its parts: the waist, distal pole, and proximal pole.
To palpate the anatomic snuffbox for the waist examination, palpate just distal to the radial styloid in the “soft spot.”
The distal pole should be palpated at the scaphoid tubercle on the palmar aspect of the wrist. To do this, place the index finger in the anatomic snuffbox and place the thumb on the palmar aspect just distal to the anatomic snuffbox. The prominent bone palpated is the distal pole of the scaphoid. With radial deviation of the wrist, this prominence should move palmarly toward the examiner’s thumb. This distal pole should be checked for tenderness
axial loading of the first metacarpal thus compressing the scaphoid
The proximal pole is just radial to this scapholunate ligament/3-4 portal area
45° pronated and supinated oblique views
scaphoid view is taken where a fist is made, with the thumb covering the dorsum of the middle phalanges of the index and middle fingers. The pronated forearm and hand are placed on the radiography table. The wrist is placed in ulnar deviation
The rationale behind this position is to take the scaphoid out of its usual position of flexion and pronation.
Ulnar deviation places the scaphoid in an extended posture and brings it more completely in view.
A clenched pencil view is also taken. This is the best view to assess associated dynamic scapholunate widening and also shows SLAC (scapholunate advanced collapse) wrist changes better than standard PA views.
* Most acutely treated scaphoid fractures require approximately 10 to12 weeks to heal
CT evaluate scaphoid fracture displacement, bony morphologic findings, gapping, sclerosis, cysts, and evidence of healing
CT is particularly helpful in addressing nonunions
(MRI) is best to determine whether there is occult scaphoid fracture. Specificity is 90% and sensitivity is between 90% and 100%
Use of MRI to assess bony vascularity is controversial – Findings of hypointense areas of bone have been suggested to be correlated with AVN.
The goal of a fracture classification is to guide management of injuries, in order to enable rapid healing with minimal complications
One of the earliest efforts to identify unstable fractures was to examine the scaphoid fracture plane
Russe classified scaphoid fractures based on the plane of the fracture into horizontal oblique, transverse, and vertical oblique
Vertical oblique fractures were unstable and difficult to control with immobilization and that they resulted in an increased rate of nonunion
Cooney and colleagues attempted to further define unstable injuries. These included fractures with more than 1 mm of displacement, a lateral intrascaphoid angle of more than 35 degrees, bone loss or comminution, perilunate fracture dislocation, DISI alignment, and proximal pole fractures.
He advocated open surgical fixation for all unstable injuries
Herbert and Fisher classified fractures based on their stability into stable acute (type A). unstable acute (type B), delayed union (type C), and nonunion (type D)
- (displacement is defined as DISI malalignment of 1 mm DISI = dorsal intercalated instability with scapholunate angle > 60 degrees and capitolunate angle >15 degrees])
Algorithm for Acute Scaphoid Fracture Management
Up to 25% of scaphoid fractures are not visible on initial radiographs
Because failure to treat a stable scaphoid fracture within 4 weeks increases the nonunion rate, all clinically suspected scaphoid fractures are treated as fractures with short-arm thumb spica cast immobilization until the cause of the symptoms is clarified
The distal pole of the scaphoid is well vascularized, and have a high rate of union after 6 to 8 weeks of plaster immobilization in a short-arm cast
Depending on the patient, a short-arm thumb spica cast or, in particularly compliant patients, a thumb spica splint has been used.
A union rate of over 95% has been shown when treatment is started within 3 weeks
some authors recommend internal percutaneous fixation for these fractures
Even if a scaphoid fracture is visible but is “nondisplaced” on radiographs, it is arguably displaced and may be seen as a flexion deformity in the sagittal plane via CT scan
Controversies include short-arm versus long-arm casting and whether to include the thumb
recommended long-arm thumb spica casting for the first 6 weeks, followed by short-arm casting until healing
Proximal pole fractures are considered unstable, whether or not they are displaced, because of their small size, their tenuous blood supply, their interarticular location, and the relatively large moment arms across the fracture site
nonunion may be attributed to impaired vascularity or instability of the proximal fragment.
any proximal pole fracture, whether nondisplaced or displaced, should be fixed operatively.
The nonunion rate is higher for proximal pole fractures if treated closed.
Because the majority of the scaphoid is covered with cartilage, fracture callus is not produced, so primary bone healing is entirely dependent on rigid stabilization of the fracture fragments until healing
Any implant used must reduce bending, shearing, and translational forces acting at a fracture site
Although K wires are easy to insert, they have a narrow role for scaphoid fixation today, given the relatively insecure fixation and minimal compression
K wire fixation must be supplemented with a cast until healing
In multitrauma situations or open fractures, rapid stabilization of an unstable scaphoid fracture
Plate fixation can be used with scaphoid nonunion humpback deformity
The headless compression screw introduced by Herbert and Fisher in 1984 has become the accepted standard surgical treatment of scaphoid fractures
FIGURE - fixation of scaphoid fracture with a headless canulated screw
The screw can be placed through dorsal or palmar approaches either by an open technique or a percutaneous technique
A small (≈2-3 cm) longitudinal or transverse incision should be made over the proximal pole at the position of the scapholunate ligament
The extensor pollicis longus (EPL) is carefully identified and the second and third dorsal compartment tendons are retracted radially
the capsule is opened with a mini inverted-“T” incision. If more exposure is necessary, a ligament-sparing approach can be used
Extreme care is taken to avoid disruption of the dorsal fibers of the SLIL when reflecting the capsular flap
Care is taken not to disrupt the blood vessels entering the waist of the scaphoid
The palmar approach may be used for waist fractures and the infrequent distal pole fracture that may require surgical fixation
Acute waist fractures can be approached dorsally or palmarly. There are advantages and disadvantages to both approaches.
The main advantage of the dorsal approach is that the fixation can get down the true axis better than the palmar approach
The disadvantages of the dorsal approach are that it either (1) requires a miniopen approach to retract extensor tendons or (2) risks injury or rupture of the extensor tendons with a percutaneous approach
The dorsal approach also requires flexion of the wrist, which may theoretically displace an unstable fracture
An advantage of the palmar approach is that the entrance of the scaphoid tubercle is subcutaneous; thus there are no tendons in the path of the approach
Another advantage of the palmar approach is that the wrist is extended, theoretically helping to reduce the fracture.
A disadvantage is that it is not possible to place the screw down the true axis of the bone because the trapezium blocks the entrance of the center of the distal scaphoid
Nonunion results from a delay in diagnosis or treatment allowing the two fracture fragments to move independent of each other creating a fibrous interphase between the distal and proximal scaphoid
Defined as a failure to heal after 6 months
Other factors that can lead to nonunion include insufficient immobilization, fracture comminution, fracture displacement, and poor patient compliance
If left untreated, scaphoid nonunion will lead to a predictable pattern of arthritic change beginning at the radial styloid articulation with the distal scaphoid pole, the radioscaphoid articalation, followed by the midcarpal joint, and ultimately by pancarpal arthritis
This sequence of changes has been termed as scaphoid nonunion advanced collapse (SNAC)
Treatment—ORIF with bone grafting if no signs of arthritis, otherwise salvage procedures such as proximal row carpectomy, subtotal wrist fusion, and total wrist fusion
Acute fracture-dislocations of the carpus are not common.
most common type of complex carpal dislocation.
Treatment of these injuries can be challenging b/c of the extensive soft tissue, cartilaginous, and bony damage
Greater arc injuries have associated fractures and; lesser arc injuries are purely ligamentous
Bone or ligament failure usually begins with the radial styloid and or scaphoid fracture or palmar capsuloligamentous disruption starting radially and propagating ulnarly
In the greater arc injury, the energy takes a transosseous route through the scaphoid, with usual disruption of the lunotriquetral interosseous (LTIO) ligament and fracture of the ulnar styloid
The proximal fragment of the scaphoid and the lunate remain with the radius, while the distal fragment of the scaphoid dislocates dorsal to the lunate with the attached distal carpal row, 10% can dislocate vollary
Variations of perilunate fracture-dislocations include fractures of the capitate, triquetrum, radial styloid, and ulnar styloid
A specific variation of the perilunate fracture-dislocation is scaphocapitate syndrome
In this injury, the injury force passes through the neck of the capitate, fracturing both the scaphoid and the capitate
The proximal portion of the capitate may rotate 90 to 180 degrees
The injury to the capitate can be missed on plain radiographs. If scaphocapitate syndrome is suspected, a CT scan will better
Both the capitate and scaphoid should be reduced and fixed with proximal to distal headless compression screws.
Nearly every combination of radiocarpal and intercarpal dislocation has been described, but few fit into a particular pattern or classification scheme
Need recognition, accurate reduction, and stable internal fixation
Internal fixation techniques depend on the pathologic condition of the carpus. Although arthroscopic techniques and fluoroscopically aided percutaneous techniques have been described the preferred treatment is an open procedure
3% of cases, a complete SLIL tear accompanies a scaphoid fracture-dislocation
The wrist is approached dorsally primarily for treatment of the scaphoid fracture or the scapholunate tear if it is a lesser arc injury
For associated lunotriquetral ligament injury, the lunotriquetral joint is reduced and held with two Kirschner wires
One technique that is very valuable and surgically efficient is to place one or two double-ended Kirschner wires from within the lunotriquetral joint out the ulnar side of the wrist through the triquetrum before the lunate is reduced
Whereas fractures of the scaphoid are relatively common, fractures of the remaining carpal bones are relatively rare
relative incidence of carpal fractures excluding the scaphoid was 1.1% of all fractures
Its frequency is often reported to be as high as 93% of all triquetral fractures
Extreme palmar flexion with radial deviation would be a primary cause for a dorsal avulsion fracture due to the attachment of the dorsal radiotriquetral and triquetroscaphoid ligaments
The most common mechanism is a fall onto a wrist in dorsiflexion and ulnar deviation
Triquetral body fractures are the second most common type of triquetral fractures
A fracture of the body of the triquetrum should alert the physician to look for associated ligamentous injuries
Fractures of the body of the triquetrum may be divided into five categories. These include sagittal fractures, fractures in the medial tuberosity, transverse fractures of the proximal pole, transverse fractures of the body, and comminuted fractures
Lastly, palmar cortical fractures have been described in the triquetrum
A patient who has a dorsal avulsion fracture is usually symptomatic with wrist flexion and extension
The lateral and oblique views most often reveal the dorsal cortical fragments
Radial deviation views are helpful to diagnose a palmar cortical fragment that may be hidden behind the hamate or remaining triquetrum
CT scans are helpful in identifying occult triquetral fractures.
Management of triquetral fractures depends on the fracture pattern
Guidelines for treatment of triquetral body fractures are less clear
Isolated triquetral body fractures can generally be treated successfully by casting and immobilization for 4 to 6 weeks
Nonunion of a triquetral body fracture is very rare
The trapezium forms a set articulation for the base of the thumb metacarpal
The palmar ridge of the trapezium projects in a palmar direction and serves as an attachment for the transverse carpal ligament
third most commonly fractured carpal bone in most authors’ series
Isolated fractures occur rarely
Fractures of the trapezium are usually associated with fractures of other bones, usually the distal radius or metacarpal
Body is common
The position of the trapezium below the thumb metacarpal generally protects it from a direct blow, making this an uncommon cause of trapezial fracture
This results in a vertical intraarticular shear fracture on the radial aspect of the trapezial body
Usually occur in association with first metacarpal or distal radius fractures
Fractures of the body of the trapezium can usually be identified on standard PA and lateral radiographic wrist views
A pronated AP view further defines the articular surface and is helpful for detecting any displacement
The Bett view is obtained with the elbow raised from the cassette, the thumb extended and abducted, and the hand partially pronated
The radial artery is at risk during the exposure and should be identified and protected during the procedure
Frequently, because of the compressive forces involved in producing the fracture, bone grafts may be needed to support the articular surface
The capitate articulates with the scaphoid and lunate proximally and is well attached along the metacarpal distally to form the central column of the hand and wrist
In the scaphocapitate perilunate fracture-dislocation
The force is initially transmitted through the scaphoid, which fractures at the waist. As the wrist continues to extend, the neck of the capitate impacts on the dorsal ridge of the radius and fractures as a result of tensile forces on the palmar aspect
As the wrist continues to go into flexion, the fractured distal portion of the capitate exerts a flexion moment to the proximal pole, which may result in complete rotation, causing the articular surface of the capitate proximal pole to face distally into the capitate fracture site.
Routine PA, lateral, and oblique radiographs are usually sufficient to diagnose a capitate fracture
Capitate neck fracture. A, Posteroanterior radiographic view of the wrist. B, Lateral radiographic view of the wrist
The head of the capitate is nearly completely covered with articular cartilage, similar to the proximal pole of the scaphoid
Like proximal pole scaphoid fractures, fractures of the head and neck of the capitate are subject to major vascular disruption and, hence, prolonged healing and poor outcome because the blood supply is retrograde
These fractures are inherently unstable and frequently lead to delayed union or nonunion. These factors need to be considered if casting and immobilization are recommended, because the several months of cast immobilization required for healing may result in additional morbidity
The capitate is repaired through a dorsal incision between the third and fourth dorsal compartments
Body fractures are rare and usually follow a direct injury to the ulnar aspect of the wrist or a dorsopalmar crush
Dorsal rim coronal fractures occur following an axial force, as in a fist fight
The hook of the hamate fracture classically occurs following a stick-handling sport like golf or hockey or following repetitive trauma from holding a handle too tightly
The nondominant hand is usually involved in golfers and baseball players, whereas the dominant hand is more likely involved in tennis and racketball players
Associated Ulnar artery/nerve injury
Late cases may even present with attritional rupture of the flexor tendons to the small and ring finger and ulnar nerve dysfunction
The most reliable diagnostic study is a CT scan
- The motor branch of the ulnar nerve runs very near the base of the hook of the hamate. It should be identified prior to excision of the hook
Pisiform fractures result from a direct blow like a fall on the palm of the hand or Eccentric load of the FCU tendon
Reverse oblique view (45-degree supination with wrist extended)
Nondisplaced to minimally displaced fracture : short-arm cast for 4 to 6 weeks
Widely displaced fracture with loss of FCU continuity: comminuted: pisiform excision and FCU repair
Malunion can lead to pisotriquetral arthritis that may require excision of the pisiform at a later date.
Excision usually does not compromise the strength of wrist flexion.
The trapezoid is well positioned between the trapezium, scaphoid, capitate, and index metacarpal
In its well protected position, the trapezoid is the least commonly fractured carpal bone
Isolated trapezoid fractures are extremely rare and usually seen along with an injury to the index finger carpometacarpal joint (CMCJ)
It is important to achieve anatomic reduction to prevent arthrosis of the CMCJ
If the fragment is small, occasionally closed reduction with cast protection may provide satisfactory results. However, if the fragments are larger, ORIF is recommended
Excision of the trapezoid is contraindicated secondary to potential proximal migration of the index metacarpal.
The lunate is well enclosed within the large lunate fossa of the distal radius. Hence, isolated fractures of the lunate body are rare
except in association with Kienbock disease (idiopathic avascular necrosis of the lunate)
common in men between the ages of 20 and 40 years. The etiology is unknown and possible causes include abnormalities in blood supply of the lunate and repetitive trauma.
Dorsal chip fractures of the lunate may be confused with dorsal fractures of the triquetrum on plain radiographs
