Proper alignment of the metatarsal heads is a critical goal in restoring the pathomechanics of the forefoot. On the AP view, a normal curved “cascade” (Lelièvre’s parabola) appearance, symmetric with the other foot, is mandatory. See illustration. This ensures that the normal length of the metatarsal is restored.
It is also critical to restore the metatarsals in their axial or horizontal plane so that in the axial or tread view all the metatarsal heads are on the same level.
Any malalignment particularly flexion will recreate focally high pressure during the stance phase and toe-off and will result in pain and subsequent callus formation.
Note that for the first ray, it is the sesamoids rather than the first metatarsal head, that bear weight, and therefore one must look at the sesamoid level in establishing the alignment in the axial or horizontal plane of the first metatarsal.
It is essential to have a healthy soft-tissue envelope prior to open intervention.
Pearl Look for damage to the plantar plate by assessing sesamoid position on an AP radiograph. Check whether they are spread apart or not. If the volar plate was avulsed, it may interpose itself into the metatarsophalangeal joint and block reduction.
2. Patient preparation
This procedure is normally performed with the patient in a supine position.
3. K-wire fixation
If the soft-tissue envelope is unsatisfactory for ORIF provisional stabilization of the first MTP joint may be performed with 2.0 mm K-wires.
However, maintaining the percutaneous pinning for six weeks, followed by a trial of nonoperative intervention is acceptable.