Rethinking Our Approach To Jones Fractures To Facilitate Shorter Post-Op Recovery
- Volume 24 - Issue 12 - December 2011
- 35736 reads
- 0 comments
A true Jones fracture involves the metaphyseal-diaphyseal junction and often enters the fourth and fifth intermetatarsal articulation. The diaphyseal stress fracture is distal to the fourth and fifth intermetatarsal articulation, and often displays significant cortical hypertrophy and medullary sclerosis. Most authors contend that the diaphyseal stress fracture is more commonly a true pathologic stress fracture due to repetitive use.5 This is in contrast to a Jones fracture, which is most commonly considered an acute injury due to a sudden axial and adduction force to the fifth metatarsal.6
However, it is my contention that these two types of fractures are more readily associated with repetitive stress overload and subsequent microfractures, and ultimately progress to macrofracture in lieu of an acute trauma.
To this point, I would encourage you to pull radiographs of patients who have had Jones fractures. Take a moment to evaluate their foot type. Do they have a cavus foot or metatarsus adductus? Chances are, patients had one or the other, whether you were dealing with a diaphyseal stress fracture or a true Jones fracture. Furthermore, is there any sclerosis or cortical hypertrophy near the fracture? If so, chances are the fracture was a result of repetitive stress, usually in a higher arched foot, with or without some acute insult. This serves as the proverbial “straw that broke the camel’s back.”
To summarize, I believe the majority of Jones fractures are true stress fractures in a vascularly compromised portion of bone found in a consistent foot type.7 This philosophy inspired the application of a different surgical technique in an attempt to address many of these observations. More than an academic exercise, it is an effort to improve and abbreviate your patient’s recovery time.
A Guide To The Surgical Technique
The technique is designed to address the factors that we know facilitate osseous healing in Jones fractures. There are three fundamental components to the procedure:
• the evacuation of sclerosed bone around the fracture and in the medullary canal;
• the introduction of healthy, autogenous bone graft; and
• the implantation of rigid internal fixation.
One would make a longitudinal incision over the fifth metatarsal shaft to the level of the fifth metatarsocuboid joint. Proceed to perform careful blunt dissection through the subcutaneous layer in an effort to protect the terminal branch/branches of the sural nerve. Identify the fracture plane. Then drive a cylindrical reamer (in this instance, a cylindrical reamer from an anterior cruciate ligament reamer system used in knee reconstruction) from lateral to medial to evacuate the bone on either side of the fracture line. Typically, the reamer is between 7 and 9 mm in diameter, and one does not drive it through the medial cortex. Remove the plug and take care to ensure the medullary canal is open distally and proximally. When it comes to extremely hard bone, it may be necessary to drill out the canal to facilitate endosteal healing.
At this point, obtain a cylindrical autogenous graft from the calcaneus through a separate incision. The diameter of this graft is typically 1 mm larger than the evacuated bone on the fifth metatarsal to ensure a snug fit in the recipient site. Take some small cancellous bone fragments from the heel and pack them up and down the medullary canal.
Proceed to place the autogenous plug into the recipient site with the lateral calcaneal cortex serving as the new fifth metatarsal cortex. A bone tamp may be necessary to accomplish a flush graft site. Finally, place a straight plate to bridge the fracture. Typically, there are two screws distal and proximal to the plug. Furthermore, drill the initial screws on either side of the graft eccentrically to compress the graft.