The carpals are the small bones of the wrist.  One of the carpals, located near the base of the thumb, is known as the scaphoid.  Fracture is another term for broken bone.  There is no difference between a fracture and a broken bone.  And so a scaphoid fracture is a broken bone in the wrist.  The scaphoid is by far the most commonly broken of the carpal bones. Scaphoid fractures usually occur as the result of a fall onto an outstretched hand.  They are more common in people under the age of 70.  People older than 70 usually break the distal radius rather than the scaphoid when they fall. People with scaphoid fractures are usually very tender over an area of the wrist known as the anatomical snuffbox.  This is a little depression between two tendons at the base of the thumb. Scaphoid fractures are usually visible on x-rays.  The x-rays are used to evaluate the fracture and form a treatment plan.  Sometimes, the scaphoid fracture is a crack that cannot be seen on the initial x-rays.  This is known as an occult fracture.  If a scaphoid fracture is suspected but not visible on x-rays, a  couple of options are  available.  First, the wrist can  be placed in a cast and  treated as if it was known to  be broken.  The cast is  removed in 10-14 days and   new x-rays obtained.  The  fracture may be more visible  after this time.  The second  option is to obtain another imaging study such as an MRI,  CT scan, or bone scan.  These studies can be helpful in  identifying or ruling out fractures that were not visible on  regular x-rays. Once the fracture has been identified, it is important to treat  it correctly.  The scaphoid has a reputation for not healing as  well as most other bones.  This is because of the way that  blood is supplied to the scaphoid.  Blood is essential for  healing because it carries nutrients to the bone that allow it  to remain healthy and heal.  Blood is supplied to the  scaphoid by small branches from the radial artery.  These  small branches enter at the end of the scaphoid nearest the  thumb.  The blood then has to travel through the bone tissue  to the other end of the scaphoid.  A fracture can interrupt this  blood flow.  If the fracture occurs at the end with poor blood  supply, it will take longer to heal.  It is also at a higher risk of  non-union, meaning that it never heals. Another complication that can occur with scaphoid fractures  is avascular necrosis (AVN).  This can occur if the fracture  is displaced enough to interrupt the blood supply from one  end of the bone to the other.  “Displaced” means that the  bone fragments are pulled apart.  If blood supply to one end  of the bone is interrupted, that part of the bone is deprived of  nutrients that it needs and can die. A third complication that can occur with scaphoid fractures is  carpal instability which can result in osteoarthritis, chronic  pain, and weakness.  There are many ligaments that hold the  carpal bones together.  They are able to move in concert to  allow for strong, smooth motion at the wrist.  If the scaphoid  does not heal correctly (malunion), it can disrupt the  mechanics of the wrist. Whether to treat a scaphoid fracture with casting or with  surgery is usually decided with the help of an orthopaedic   surgeon.  Nondisplaced fractures of the distal end or waist of  the scaphoid are usually treated with casting.  Displaced  fractures are usually treated with surgery.  Because of slow  healing and risk of non-union, fractures of the proximal  scaphoid are often treated with surgery as well. If non-operative treatment is chosen, the wrist is placed in a  long-arm thumb spica cast.  The long arm cast can be  replaced with a short arm thumb spica cast after six weeks.   Depending on where the fracture is located (remember that  fractures at the proximal end heal more slowly), the short  arm cast is left in place for six to ten weeks.  Because the  wrist is immobilized for a long period of time, it will be stiff  and weak after the cast is removed.  Physical therapy can  help to improve range of motion and strength. Surgical treatment involves using a screw to compress the  fragments together.  This gives the scaphoid a better chance  of healing correctly and more quickly.  A thumb spica cast  may still be applied after surgery, but does not have to be  applied for as long as a cast would if the fracture were  treated non-operatively.  Physical therapy may be necessary  as the fracture heals.