Current Insights On Treating Second MPJ Dysfunction
- Volume 24 - Issue 2 - February 2011
- 20475 reads
- 5 comments
With the metatarsal head disarticulated, it is easiest to evaluate the plantar plate from this dorsal approach. In my limited experience with this procedure, the plate itself is not usually deviated in a direction commensurate with the subluxation of the digit. Homologous to the relationship between the first metatarsal head and the sesamoid apparatus, it is the metatarsal head that seems to be shifted out of position.8 Once one has decompressed the joint, the realignment of the metatarsal osteotomy restores the anatomic relationship between the plantar plate and the metatarsal head.
Once you have realigned the metatarsal head and re-established the coaxial orientation of the proximal phalanx and the metatarsal, the toll that subluxation has taken on the cartilage surfaces of the joint becomes apparent. The flattened condition of the lateral base of the proximal phalanx and the head of the metatarsal head is evident by the increase in lateral MPJ joint space, which can result from prolonged subluxation.
With this realignment complete, the focus shifts to stabilization of the ray, which is the final task in completing the procedure. Take note that there has been no violation of the digit itself and no digital incision beyond the level of the proximal phalanx. In addition, one has not performed bone resection, arthroplasty or arthrodesis.
There is a positive point associated with this technique. One may reduce chronic edema by avoiding soft tissue dissection and resection of bone in the small space of the digital compartment. This is an important difference in comparison to the more traditional forms of sequential reduction and digital stabilization that require a significant amount of trauma to the digit.
In addition, by using this suture and button technique to stabilize the MPJ and plantar plate, the surgeon may reduce or avoid the development of profound residual edema, referred to as “the sausage toe,” which is often the source of patient dissatisfaction after digital surgery.
Additional Insights On Suturing
The surgeon can achieve actual stabilization of the plantar plate with a suture and button technique. I have chosen to use absorbable suture in lieu of leaving a non-absorbable material in the small compartment of the lesser MPJs. If one employs a non-absorbable suture, the suture acts as a residual foreign body, potentially increasing the residual postoperative edema. From a purist standpoint, absorbable material is not permanent and the inflammatory reaction associated with it is limited by the half-life of the material versus its non-absorbable counterpart.
With the joint exposed and the metatarsal osteotomy complete and stabilized, one can direct attention to the compartment of the MPJ. Load absorbable 3.0 vicryl on a Keith needle. First, run the material alongside the metatarsal head at the level of the anatomic neck through the plantar plate and out the bottom of the foot.
Then extend the suture across the metatarsal neck and run it through the opposite side of the plantar plate, and out the ball of the foot. This suture lassoes the metatarsal neck and allows stabilization of the plantar plate beneath the metatarsal head.
In addition, the suture lassoes the phalangeal base over the extensor digitorum longus tendon (EDL). There is no tension along the digits despite loading of the forefoot. This is due to the virtual lengthening of the EDL tendon given the shortening of the metatarsal.
Prepare the suture and run it along the sides of the base of the proximal phalanx. Secure the plantar plate with each run of the suture medially and laterally. Secure the four free suture ends outside the ball of the foot to a sterile button using a chain of five or more hand ties.