Jones fracture

This article is about fifth metatarsal diaphysis fracture. For fifth metatarsal tuberosity fracture, see Pseudo-Jones fracture.

Jones fracture
Specialty	Emergency medicine

Jones fracture X-ray.

This is a pseudo-Jones fracture X-ray

A Jones fracture is a fracture of the diaphysis of the fifth metatarsal of the foot, at the base of the small toe. The proximal end, where the Jones fracture occurs, is in the midportion of the foot. Patients who sustain a Jones fracture have pain over this area, swelling, and difficulty walking. The fracture was first described by British orthopedic surgeon Sir Robert Jones who sustained this injury himself (while dancing) and reported it in the Annals of Surgery in 1902.

Diagnosis

A patient with a Jones fracture may not realize that a fracture has occurred. Diagnosis includes the palpation of an intact peroneus brevis tendon, and demonstration of local tenderness distal to the tuberosity of the fifth metatarsal, and localized over the diaphysis of the proximal metatarsal. Bony crepitus is unusual. Diagnostic x-rays include anteroposterior, oblique, and lateral views and should be made with the foot in full flexion.

Treatment

If a Jones fracture is not significantly displaced, it can be treated with a cast, splint or walking boot for four to eight weeks. Patients should not place weight on the foot until instructed by their doctor. Three-fourths of fractures treated like this should heal.

In the case of acute fracture in an athlete, a dynamic compression plate can be placed on the tension side of the fracture, K-Wire with monofilament wire in a figure 8 fashion due to the nature of a transverse fracture. Internal fixation with cortical or cancellous screw would require an oblique fracture that could be addressed through "The rule of 2's" in regards to Internal fixation with screws.

Other treatments commonly encouraged are increased intake of vitamin D and calcium.

This injury must be differentiated from the physiologic developmental apophysis commonly and normally occurring at this site in adolescents. Differentiation is possible by characteristics such as absence of sclerosis of the fractured edges (in acute cases) and orientation of the lucent line: transverse (at 90 degrees) to the metatarsal axis for the fracture (due to avulsion pull by the peroneus brevis muscle inserting at the proximal tip) - and parallel to the metatarsal axis in the case of the apophysis.

Prognosis

If a Jones fracture fails to unite (malunion or non union), which is a common problem with these fractures, it can become a chronic condition. If this is the case, podiatrists will likely recommend that the patient spend more time in a cast, up to twenty weeks.

For several reasons, a Jones fracture often does not heal. The diaphyseal bone, where the fracture occurs, is an area of poor blood supply. In medical terms, it is a watershed area between two blood supplies. This makes healing difficult. In addition, there are various tendons, including the peroneus brevis and fibularis tertius, and two small muscles attached to the bone. These may pull the fracture apart and prevent healing.

Other proximal fifth metatarsal fractures

Other proximal fifth metatarsal fractures exist, although they are not as severe as a Jones fracture. If the fracture enters the intermetatarsal joint, it is a Jones fracture. If, however, it enters the tarsometatarsal joint, then it is an avulsion fracture caused by pull from the peroneus brevis. An avulsion fracture is sometimes called a Pseudo-Jones fracture or a Dancer's fracture.

External links

• Jones fracture - wheelessonline.com