A Bennett fracture is an injury to the base of the thumb joint usually caused by a hard impact or trauma such as punching something hard or falling onto the hand with the thumb sticking out to the side. It is a serious injury and will require surgery to avoid long term complications.
Symptoms will be similar to other wrist and hand fractures with immediate and severe pain over the thumb side of the wrist. There will be rapid swelling and bruising may develop. The patient will find it very difficult to move the wrist and thumb experiencing a lot of pain. In more serious cases the thumb may appear deformed.
What is a Bennett's fracture?
It is a fracture and dislocation of the joint at the base of the thumb where the carpal bone meets the metacarpal bone ( known as the first carpometacarpal joint). A small part of the metacarpal bone will remain attached to the volar ligament while the main part of the bone is dislocated. It is similar to a Rolando fracture which is also a fracture to the base of the thumb but with more serious fragmenting of bones.
A Bennett fracture is a serious injury which if not treated correctly can cause permanent disability. In particular problems when bringing the thumb across the palm of the hand and pinching with the index or middle fingers are common if the fracture does not heal properly.
Bennett fracture surgery
Mr. Elliot Sorene MBBS FRCS (Tr & Orth) EDHS Consultant Orthopaedic, Hand & Upper Limb Surgeon talks about surgery for Bennett's Fracture
A Bennett fracture usually requires surgery performed by a specialist wrist and hand surgeon followed by a 4-6 week period of immobilization in a Plaster cast. The operation involves reduction of the bones which is medical speak for putting them back in the correct place and fixation of the fracture using wires.
Following the immobilization period, mobilization of the surrounding joints by a physical therapist is important to help restore normal function. This should be followed by wrist and hand strengthening exercises. On returning to sport, a protective thumb splint, support or taping may be used.
They are seen a lot in rugby players and other contact sports. The Bennett fracture is a more simple fracture where just one piece of bone pops out at the bottom. The Rolando fracture is a more complicated fracture where a number of pieces of bone break or shatter.
These fractures can be extremely difficult to treat conservatively (without surgery) unless the bones have not moved at all. If the bones are displaced then this type of fracture will require surgery and fixation of the bones.
There are however a number of modern methods to treat these injuries surgically. The Rolando fracture can be operated on with locking plates and small screws which hold the fracture fragments in place. A simpler Bennett fracture can be wired but whatever the surgery these injuries will require a full rehabilitation and exercise program to restore mobility and strength.
Following surgery the wrist may be in plaster for a period of 6 weeks or possibly using a removable splint rather than a fixed plaster cast. Eventually if the bones are restored to their correct positions the patient will get a good result and restore decent function to the wrist.