Because blood supply is needed to heal a fracture, the scaphoid often takes a long time a few months to heal. The scaphoid is the most commonly fractured carpal bone and is reported to account for up to 90% of all carpal fractures. Displaced scaphoid fractures are seen on radiographs. This limited arterial supply to the proximal portion, is clinically significant in scaphoid fractures which are very common injuries following a fall on an outstretched hand and can result in avascular necrosis of the proximal segment, or other complications such as nonunionmalunion. The scaphoid tubercle is a bony prominence on the ventral surface of the lateral portion of the distal pole.
Bipartite scaphoids may be unilateral or bilateral diagnostic criteria have been proposed 3 no history of traumatic injury. There is a prominent bony bulge on the back surface of the lateral side of the distal pole, known as the scaphoid tubercle 3 the scaphoid articulates with four of the wrist bones the lunate, capitate. Narrow area of its waist and even smaller distal portion, are accessible to blood vessels distally, it articulates with the trapezium and trapezoid in a. This can sometimes be disrupted by a crack across the waist of the bone. Delayed union, malunion, or nonunion are often associated with fractures that are inadequately immobilized. Fracture proximal to the perforating vessels on the dorsoradial surface of the scaphoid can cause significant bone ischemia of the proximal pole. This complication is influenced by delayed diagnosis, gross displacement, associated injuries of the carpus, and impaired blood supply. The scaphoid is situated between the proximal and distal rows of carpal bones.
Diagnosis and management of scaphoid fractures american. Management for an acute scaphoid fracture begins with. The proximal pole depends on blood supply from the distal pole through the scaphoid bone. Fractures in the proximal have a high incidence of avn 30%. Dec 18, 2017 scaphoid fractures can lead to nonunion and avascular necrosis due to interruption of the blood supply. Seventy to eight percent of the intraosseous vascularity and the entire. Management for an acute scaphoid fracture begins with a reduction.
Scaphoid bone musculoskeletal, skeletal anatomyzone. Current methods of diagnosis and treatment of scaphoid. As such, the scaphoid is perfused in the distal to proximal direction retrograde blood supply. In surgical treatment, holes are drilled and a screw is placed across the fracture to realign the bones and support the site while it heals. Scaphoid anatomy and structure surfaces and articulations. Scaphoid fractures may be radiologicallyoccult in the acute setting and may result in. Normal scaphoid anatomy slide 1 and blood supply slide 2. Of these fractures, 40% are undiagnosed at the time of original injury. A bipartite scaphoid is a rare example of a divided carpus.
Waldman md, jd, in atlas of uncommon pain syndromes third edition, 2014. Livro viagem a ixtlan pdf american academy of orthopaedic surgeons. Scaphoid fractures can lead to nonunion and avascular necrosis due to interruption of the blood supply. Blood supply major blood supply is dorsal carpal branch branch of the radial artery enters scaphoid in a nonarticular ridge on the dorsal surface and supplies proximal 80% of scaphoid via retrograde blood flow. Get a printable copy pdf file of the complete article 819k, or click on a page image. Each chapter covers a different procedure, beginning with a discussion of relevant anatomical. Scaphoid fractures that do not heal are referred to as a scaphoid nonunion. The extraosseous and intraosseous blood supply of the scaphoid bone. The major blood supply to the scaphoid is via the radial artery. Basic sciences blood supply of the scaphoid youtube. The ability of eswt to enhance microcirculation parameters in soft tissue was of interest to determine if it improves microcirculation in the. Review of the current methods in the diagnosis and. Avascular necrosis avn is a common complication of a scaphoid fracture.
Nonunion is directly related to an interruption of the tenuous blood supply to the scaphoid. Key steps in the management of a scaphoid nonunion are correcting any intrascaphoid deformity, such as the humpback deformity, realigning the. The scaphoid bone, also called the navicular bone, is the largest bone in the proximal row of the wrist, the highly flexible region between the forearm and the hand. Sometimes a scaphoid non union is found quite by chance when xrays are taken of the wrist for other reasons. The scaphoid blood supply comes from the dorsal branch of the radial artery coursing retrograde proximal 80% of scaphoid and superficial palmar arch distal 20% of scaphoid. Scaphoid blood supply two major vascular pedicles1. The scaphoid receives its primary blood supply from the dorsal scaphoid branches of the radial artery, which enter the scaphoid at a point near the distal pole.
The fracture can disrupt the bones blood supply, impairing the healing. This blood supply is easily disrupted, often leaving the proximal. Fractures of the scaphoid bone mainly occur in young adults and constitute 27% of all fractures. The scaphoid brings together in one definitive reference every aspect of carpal scaphoid injury treatment. Because the scaphoid has a blood supply which comes from only one side it is prone to not healing. Unlike most bones the scaphoid bone has a fragile blood supply. Because of the tenuous blood supply, a scaphoid fracture can sever this blood flow and stop the delivery of necessary oxygen and nutrients to the bone cells. Whilst most scaphoid fractures may heal, a number of case series have identified a 10%15% nonunion rate. Ultimately, scaphoid nonunions can lead to loss of wrist motion and eventual wrist arthritis.
The blood supply of the entire scaphoid is derived from vessels entering the distal portion of the bone. The blood supply to the scaphoid comes from two branches of the radial artery. The laterovolar and the dorsal systems shared in the supply of the proximal two thirds of the scaphoid, while the distal group remained very see figure in the pdf file much circumscribed to the. Over 80% of the bone is covered in articular cartilage. Scaphoid spans both carpal rows and therefore has less mobility than other carpal bones. Open repair and internal fixation with a screw represents the golden standard. To avoid missing this diagnosis, a high index of suspicion and a thorough history and. The geometry of the scaphoid as it relates to its retrograde blood supply renders it particularly prone to avascular necrosis and other fracture complications.
The scaphoid also known as the os scaphoideum or historically as the navicular is the largest of the proximal row of carpal bones and forms the radial portion of the carpal tunnel. Blood flow in the scaphoid is improved by focused extracorpo. Bipartite scaphoids may be unilateral or bilateral. The scaphoid bone is the largest bone of the proximal row of wrist bones, its long axis being from above downward, lateralward, and forward. Enter through numerous small foramina along the spiral groove and dorsal ridge. Radiolucency around a 12 days old scaphoid fracture that was initially barely visible. Healing time in a cast can range from 610 weeks and even longer.
If the scaphoid is broken, the few tiny blood vessels that supply the bone with nutrients can be damaged. The scaphoid serves as a bridge between the proximal and the distal carpal bones and transfers compression loads from the hand to the forearm and it has a major role in maintaining carpal stability. If that supply is cut off by a fracture in the neck or proximal third of the scaphoid, the entire bone is in jeopardy, as the bone will not receive the nourishment it needs to repair itself. The palmar surface of the scaphoid is concave, and forming a tubercle, giving attachment. The waist between the two is the commonest site of scaphoid fracture. It is located on the radial side of the wrist, and articulates with the radius, lunate, trapezoid, trapezium and capitate.
The extraosseous and intraosseous vascularity of the carpal scaphoid was studied in 15 fresh cadaver specimens by injection and clearing techniques. When this occurs, healing can be slow, and the scaphoid fracture may not heal at all. The flexibility of the wrist can be largely attributed to its unique and complex composition, marked by. The anatomic snuffbox is generally tender and swelling may occur.
The blood supply of the scaphoid is unique and tenuous. Its unique morphology from its boat like shape to its retrograde blood supply can present with challenges in the. Since the scaphoid blood supply comes from two different vascular branches of the radial artery, fractures can limit access to blood supply. Review of the current methods in the diagnosis and treatment. The extraosseous and intraosseous blood supply of the scapho. Due to this perfusion pattern, the scaphoid bone is prone to nonunion after fracture. Hence longer and larger screws may be required in males.
The scaphoid can be injured when a significant load is placed on the extended wrist, such as a fall onto an outstretched hand. Nov 23, 2019 this unusual flow of blood in the scaphoid presents a problem when you sustain a scaphoid fracture. The extraosseous and intraosseous blood supply of the. Scaphoid fractures musculoskeletal medicine for medical. Scaphoid fracture causes, symptoms, diagnosis, and treatment. Due to its poor blood supply, healing of a fractured scaphoid can be difficult but is important to wrist function and longterm health. Scaphoid represent floor of the anatomic snuff box. Request pdf the blood supply of the scaphoid bone scaphoid vascularisation was investigated using macroscopic and microscopic techniques in 12. In case of a proximal scaphoid fracture, the blood. The scaphoid is the most commonly fractured carpal bone accounting for 60% of fractures 1, 2. The scaphoid bone is one of eight small bones in the wrist, called carpal bones. The use of the free vascularised bone graft for nonunion. It is an irregularly shaped tubular bone, twisted and bends into sshape. Scaphoid fractures only account for 2% of all fractures but is second only to femoral head for posttraumatic avn.
Apr 22, 20 scaphoid blood supply two major vascular pedicles1. Imaging and treatment of scaphoid fractures and their. Current methods of diagnosis and treatment of scaphoid fractures. Dec 08, 2016 how to draw the blood supply of the scaphoid, frcs orth revision. Biomechanics mechanically scaphoid links the proximal and distal rows. Osteonecrosis is said to occur in %50% of cases of fracture of the scaphoid, and the incidence of osteonecrosis is even higher in those with involvement of the proximal one. The radial artery is the primary source of blood supply to the scaphoid. Full text get a printable copy pdf file of the complete article 819k, or click on a page image below to browse page by page. When the scaphoid bone is broken, it may not heal properly because it has a very fragile blood supply.
Key steps in the management of a scaphoid nonunion are correcting any intra scaphoid deformity, such as the humpback deformity, realigning the. Scaphoid fractures are easy to detect and manage matt woronczak scott anderson. The specific blood supply in combination with the demanding functional requirements can easily lead to disturbed fracture healing. Xrays are routinely taken of the scaphoid as it heals. Treatment of problem fractures and nonunions of the scaphoid. This blood supply is easily disrupted, often leaving the proximal portion of the bone without nutrition and leading to osteonecrosis figure 401. Featuring insights from pioneers in the field, its comprehensive coverage extends from standard open procedures to stateoftheart percutaneous methods and miniincision techniques.
Complications may include nonunion of the fracture, avascular necrosis, and arthritis scaphoid fractures are most commonly caused by a fall on an outstretched hand. Like the scaphoid bone of the wrist, the elbow joint is extremely susceptible to this disease because of the tenuous blood supply of the articular cartilage. The scaphoid bone is one of the carpal bones of the wrist. The blood supply of the scaphoid is primarily from the radial artery via the artery to. Microcirculation is an important factor in bone healing and may be compromised in fractured scaphoids because its blood supply comes from the distal end. Then, the fracture will be fixed with a compression screw. A good blood supply of the scaphoid bone from palmar, dorsal and radial vessel groups with a variety of anastomoses was found which should. Scaphoid nonunion s caphoid nonunion is challenging to manage because of the geometry of the scaphoid, the direction andtypeoffracture,andthevascular pattern of the blood supply to the scaphoid.
Most of the blood supply derives from branches of the radial artery that penetrate the scaphoid distally and supply 70%80% of the. This wrist bone resembles a medium cashew in size and shape 7, with the two sides identified as the distal and proximal poles. Symptoms generally includes pain at the base of the thumb which is worse with use of the hand. There is controversy whether this condition is congenital i. Risk of avn depends on the location of the fracture. Blood vessels enter through the dorsal ridge and tuberosity. Ender, mdmost fractures of the scaphoid 90% can be treated nonoperati vely with good results. When applied to the proximal pole of the scaphoid, this showed the venous drainage to be via the dorsal ridge into the venae comitantes of the radial artery. The scaphoid is vitally important for the proper mechanics of wrist function. The proximal vessel seen in one specimen was of very small caliber and limited penetration.
A scaphoid navicular fracture is a break in one of the small bones of the wrist. Jul 01, 2019 since the scaphoid blood supply comes from two different vascular branches of the radial artery, fractures can limit access to blood supply. Osteonecrosis of the elbow joint is an often missed diagnosis. The diagnostic strategy of suspected scaphoid fractures, however, is surrounded by controversy.
Diagnosis patients with a scaphoid nonunion usually present with a history of previous. It is situated between the hand and forearm on the thumb side of the wrist also called the lateral or radial side. A scaphoid fracture is a break of the scaphoid bone in the wrist. No direct blood supply to proximal portion of the bone. A good blood supply of the scaphoid bone from palmar, dorsal and radial vessel groups with a variety of anastomoses provide sufficient collateral blood flow from adjacent regions. May 10, 2015 anatomy scaphoid is the largest bone of proximal carpal row. This type of fracture occurs most often after a fall onto an outstretched hand. The palmar scaphoid branch arises from the superficial palmar. The scaphoid can be divided into proximal and distal poles. Symptoms of a scaphoid fracture typically include pain and tenderness in the area just below the base of. Scaphoid carries the compressive loads from the hand across the wrist to the distal forearm. An animated description of the blood supply to the scaphoid and its impact on fracture healing. How to draw the blood supply of the scaphoid, frcs orth revision. The scaphoid bone forms part of the wrist joint and interacts with the radius.
The blood supply of the scaphoid comes scaphoid fracture is a common injury encountered in family medicine. Scaphoid blood flow and acute fracture healing semantic scholar. A separate volar arterial branch to the scaphoid enters the tubercle and accounts for 2030% of the scaphoids blood supply, mainly to the distal. Trabecular density is maximum at the proximal pole and thinnest at the waist. It is important for stability and movement at the wrist and may be fractured after a fall onto a hyperextended hand. Treatment of scaphoid fractures if the fracture is nondisplaced, it can be treated by immobilization in a cast that usually covers the forearm, hand, and thumb, and sometimes includes the elbow for the first phase of immobilization. Articular surface 75% of scaphoid bone is covered by articular cartilage. The laterovolar and the dorsal systems shared in the supply of the proximal two thirds of the scaphoid, while the distal group remained very see figure in the pdf file much circumscribed to the supply of the tuberosity. Scaphoid bone definition, location, anatomy, diagram. Scaphoid fractures and blood supply nabil ebraheim medium. Since blood supply is available from the palmar circulation, a dorsal approach to the scaphoid bone is possible. Archived from the original on december 7, access to the pdf text. The scaphoid does not have any tendinous attachments.
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