Scaphoid fracture | |
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Other names | Carpal scaphoid fracture, carpal navicular fracture [1] |
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An X-ray showing a fracture through the waist of the scaphoid | |
Specialty | Hand surgery, emergency medicine |
Symptoms | Pain at the base of the thumb, swelling [2] |
Complications | Nonunion, avascular necrosis, arthritis [2] [1] |
Types | Proximal, medial, distal [2] |
Causes | Fall on an outstretched hand [2] |
Diagnostic method | Examination, X-rays, MRI, bone scan [2] |
Differential diagnosis | Distal radius fracture, De Quervain's tenosynovitis, scapholunate dissociation, wrist sprain [2] [1] |
Prevention | Wrist guards [1] |
Treatment | Not displaced: Cast [2] Displaced: Surgery [2] |
Prognosis | Healing may take up to six months [1] |
A scaphoid fracture is a break of the scaphoid bone in the wrist. [1] Symptoms generally includes pain at the base of the thumb which is worse with use of the hand. [2] The anatomic snuffbox is generally tender and swelling may occur. [2] Complications may include nonunion of the fracture, avascular necrosis of the proximal part of the bone, and arthritis. [2] [1]
Scaphoid fractures are most commonly caused by a fall on an outstretched hand. [2] Diagnosis is generally based on a combination of clinical examination and medical imaging. [2] Some fractures may not be visible on plain X-rays. [2] In such cases the affected area may be immobilised in a splint or cast and reviewed with repeat X-rays in two weeks, or alternatively an MRI or bone scan may be performed. [2]
The fracture may be preventable by using wrist guards during certain activities. [1] In those in whom the fracture remains well aligned a cast is generally sufficient. [2] If the fracture is displaced then surgery is generally recommended. [2] Healing may take up to six months. [1]
It is the most commonly fractured carpal bone. [3] Males are affected more often than females. [2]
People with scaphoid fractures generally have snuffbox tenderness.
Focal tenderness is usually present in one of three places: 1) volar prominence at the distal wrist for distal pole fractures; 2) anatomic snuff box for waist or midbody fractures; 3) distal to Lister's tubercle for proximal pole fractures. [4]
Avascular necrosis (AVN) is one complication of scaphoid fracture. Since the scaphoid receives its arterial supply in a retrograde fashion (i.e. from distal to proximal pole), the part proximal to the fracture is usually affected. [5]
Risk of AVN depends on the location of the fracture.
Non union can also occur from undiagnosed or undertreated scaphoid fractures. Arterial flow to the scaphoid enters via the distal pole and travels to the proximal pole. This blood supply is tenuous, increasing the risk of nonunion, particularly with fractures at the wrist and proximal end. [4] If not treated correctly non-union of the scaphoid fracture can lead to wrist osteoarthritis.[ citation needed ]
Symptoms may include aching in the wrist, decreased range of motion of the wrist, and pain during activities such as lifting or gripping. If x-ray results show arthritis due to an old break, the treatment plan will first focus on treating the arthritis through anti-inflammatory medications and wearing a splint when an individual feels pain in the wrist. If these treatments do not help the symptoms of arthritis, steroid injections to the wrist may help alleviate pain. Should these treatments not work, surgery may be required. [6]
Fractures of scaphoid can occur either with direct axial compression or with hyperextension of the wrist, such as a fall on the palm on an outstretched hand. Using the Herbert classification system, there are three main types of scaphoid fractures. 10%-20% of fractures are at the proximal pole, 60%-80% are at the waist (middle), and the remainder occur at the distal pole. [4] [7] [8]
Scaphoid fractures are often diagnosed using plain radiographs and multiple views are obtained as standard. [9] However, not all fractures are apparent initially. [7] In 1/4 of cases, the clinical examination suggests a fracture, but the X-ray does not show it, even though there is indeed a fracture. [10] Therefore, people with tenderness over the scaphoid (those who exhibit pain to pressure in the anatomic snuff box ) are often splinted in a thumb spica for 7–10 days at which point a second set of X-rays is taken. [7] If a minimally displaced fracture was present initially, healing will now be apparent. Even then a fracture may not be apparent. A CT Scan can then be used to evaluate the scaphoid with greater resolution. The use of MRI, if available, is preferred over CT and can give one an immediate diagnosis. [11] Bone scintigraphy is also an effective method for diagnosis fracture which do not appear on Xray. [12]
Treatment of scaphoid fractures is guided by the location in the bone of the fracture (proximal, waist, distal), displacement (or instability) of the fracture, and patient tolerance for cast immobilization.[ citation needed ]
For non and minimally displaced fractures (up to 2mm) of the scaphoid waist, cast immobilisation (with surgical fixation for non-united fractures at 6 to 12 weeks) is as effective as immediate surgery fixation. This was demonstrated by the SWIFFT (Scaphoid Waist Internal Fixation for Fractures Trial) study, 439 patients were randomly allocated to either cast immobilisation or surgical fixation. There was no difference in the healing, pain and function or days off work between the two treatment groups, the cast immobilisation group had less complications and this treatment was more cost effective. [14] [15] The choice of short arm, short arm thumb spica or long arm cast is debated in the medical literature and no clear consensus or proof of the benefit of one type of casting or another has been shown; although it is generally accepted to use a short arm or short arm thumb spica for non displaced fractures. [7] In the SWIFFT study most used a short arm cast with the thumb left free. Non displaced or minimally displaced fracture can also be treated with percutaneous or minimal incision surgery which if performed correctly has a high union rate, low morbidity and faster return to activity than closed cast management. [16] However this was not confirmed by the SWIFFT study. [14] [15]
Fractures that are more proximal take longer to heal. It is expected the distal third will heal in 6 to 8 weeks, the middle third will take 8–12 weeks, and the proximal third will take 12–24 weeks. [7] [8] The Scaphoid receives its blood supply primarily from lateral and distal branches of the radial artery. Blood flows from the top/distal end of the bone in a retrograde fashion down to the proximal pole; if this blood flow is disrupted by a fracture, the bone may not heal. Surgery is necessary at this point to mechanically mend the bone together.[ citation needed ]
Percutaneous screw fixation is recommended over an open surgical approach when it is possible to achieve acceptable bone alignment closed as minimal incisions can preserves the palmar ligament complex and local vasculature, and help avoid soft tissue complications. This surgery includes screwing the scaphoid bone back together at the most perpendicular angle possible to promote quicker and stronger healing of the bone. Internal fixation can be done dorsally with a percutaneous incision and arthroscopic assistance [17] or via a minimal open dorsal approach, [16] or via a volar approach in which case slight excavation of the edge of the trapezium bone may be necessary to reach the scaphoid as 80% of this bone is covered with articular cartilage, which makes it difficult to gain access to the scaphoid. [18]
A non-union (pseudarthrosis) can occur in 2 to 5% of cases. [19]
In the aftermath, 90% of non-operated individuals return to sports, with 88% reaching their previous level. Among those who underwent surgery, the rate of returning to sports is 98%, and 96% return to their previous level. The average time observed for resuming sports is 14 weeks for non-operated individuals and 7 weeks for those who had surgery. [20]
Fractures of the scaphoid are common in young males. [21] They are less common in children and older adults because the distal radius is weaker contributor to the wrist and more likely to fracture in these age groups. [7] Scaphoid fractures account for 50%-80% of carpal injuries. [8]
These are also called navicular fractures (the scaphoid also being called the carpal navicular), although this can be confused with the navicular bone in the foot.[ citation needed ]
In human anatomy, the wrist is variously defined as (1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; (2) the wrist joint or radiocarpal joint, the joint between the radius and the carpus and; (3) the anatomical region surrounding the carpus including the distal parts of the bones of the forearm and the proximal parts of the metacarpus or five metacarpal bones and the series of joints between these bones, thus referred to as wrist joints. This region also includes the carpal tunnel, the anatomical snuff box, bracelet lines, the flexor retinaculum, and the extensor retinaculum.
The anatomical snuff box or snuffbox or foveola radialis is a triangular deepening on the radial, dorsal aspect of the hand—at the level of the carpal bones, specifically, the scaphoid and trapezium bones forming the floor. The name originates from the use of this surface for placing and then sniffing powdered tobacco, or "snuff." It is sometimes referred to by its French name tabatière.
The trapezoid bone is a carpal bone in tetrapods, including humans. It is the smallest bone in the distal row of carpal bones that give structure to the palm of the hand. It may be known by its wedge-shaped form, the broad end of the wedge constituting the dorsal, the narrow end the palmar surface; and by its having four articular facets touching each other, and separated by sharp edges. It is homologous with the "second distal carpal" of reptiles and amphibians.
The scaphoid bone is one of the carpal bones of the wrist. It is situated between the hand and forearm on the thumb side of the wrist. It forms the radial border of the carpal tunnel. The scaphoid bone is the largest bone of the proximal row of wrist bones, its long axis being from above downward, lateralward, and forward. It is approximately the size and shape of a medium cashew nut.
The capitate bone is a bone in the human wrist found in the center of the carpal bone region, located at the distal end of the radius and ulna bones. It articulates with the third metacarpal bone and forms the third carpometacarpal joint. The capitate bone is the largest of the carpal bones in the human hand. It presents, above, a rounded portion or head, which is received into the concavity formed by the scaphoid and lunate bones; a constricted portion or neck; and below this, the body. The bone is also found in many other mammals, and is homologous with the "third distal carpal" of reptiles and amphibians.
A Colles' fracture is a type of fracture of the distal forearm in which the broken end of the radius is bent backwards. Symptoms may include pain, swelling, deformity, and bruising. Complications may include damage to the median nerve.
A bone fracture is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a comminuted fracture. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta, where the fracture is then properly termed a pathologic fracture.
A distal radius fracture, also known as wrist fracture, is a break of the part of the radius bone which is close to the wrist. Symptoms include pain, bruising, and rapid-onset swelling. The ulna bone may also be broken.
Avascular necrosis (AVN), also called osteonecrosis or bone infarction, is death of bone tissue due to interruption of the blood supply. Early on, there may be no symptoms. Gradually joint pain may develop, which may limit the person's ability to move. Complications may include collapse of the bone or nearby joint surface.
The triangular fibrocartilage complex (TFCC) is formed by the triangular fibrocartilage discus (TFC), the radioulnar ligaments (RULs) and the ulnocarpal ligaments (UCLs).
Gamekeeper's thumb is a type of injury to the ulnar collateral ligament (UCL) of the thumb. The UCL may be merely stretched, or it may be torn from its insertion site into the proximal phalanx of the thumb; in approximately 90% of cases part of the bone is actually avulsed from the joint. This condition is commonly observed among gamekeepers and Scottish fowl hunters, as well as athletes. It also occurs among people who sustain a fall onto an outstretched hand while holding a rod, frequently skiers grasping ski poles.
Percutaneous pinning is a technique used by orthopedic and podiatric surgeons for the stabilization of unstable fractures. Percutaneous pinning involves inserting wires through a person's skin for stabilizing the fractured bone.
Preiser disease, or (idiopathic) avascular necrosis of the scaphoid, is a rare condition where ischemia and necrosis of the scaphoid bone occurs without previous fracture. It is thought to be caused by repetitive microtrauma or side effects of drugs in conjunction with existing defective vascular supply to the proximal pole of the scaphoid. MRI coupled with CT and X-ray are the methods of choice for diagnosis.
Bennett fracture is a type of partial broken finger involving the base of the thumb, and extends into the carpometacarpal (CMC) joint.
A humerus fracture is a break of the humerus bone in the upper arm. Symptoms may include pain, swelling, and bruising. There may be a decreased ability to move the arm and the person may present holding their elbow. Complications may include injury to an artery or nerve, and compartment syndrome.
A supracondylar humerus fracture is a fracture of the distal humerus just above the elbow joint. The fracture is usually transverse or oblique and above the medial and lateral condyles and epicondyles. This fracture pattern is relatively rare in adults, but is the most common type of elbow fracture in children. In children, many of these fractures are non-displaced and can be treated with casting. Some are angulated or displaced and are best treated with surgery. In children, most of these fractures can be treated effectively with expectation for full recovery. Some of these injuries can be complicated by poor healing or by associated blood vessel or nerve injuries with serious complications.
Internal fixation is an operation in orthopedics that involves the surgical implementation of implants for the purpose of repairing a bone, a concept that dates to the mid-nineteenth century and was made applicable for routine treatment in the mid-twentieth century. An internal fixator may be made of stainless steel, titanium alloy, or cobalt-chrome alloy. or plastics.
An ulna fracture is a break in the ulna bone, one of the two bones in the forearm. It is often associated with a fracture of the other forearm bone, the radius.
Wrist osteoarthritis is gradual loss of articular cartilage and hypertrophic bone changes (osteophytes). While in many joints this is part of normal aging (senescence), in the wrist osteoarthritis usually occurs over years to decades after scapholunate interosseous ligament rupture or an unhealed fracture of the scaphoid. Characteristic symptoms including pain, deformity and stiffness. Pain intensity and incapability are notably variable and do not correspond with arthritis severity on radiographs.
A broken finger or finger fracture is a common type of bone fracture, affecting a finger. Symptoms may include pain, swelling, tenderness, bruising, deformity and reduced ability to move the finger. Although most finger fractures are easy to treat, failing to deal with a fracture appropriately may result in long-term pain and disability.