Point-Counterpoint: Is The Dorsal Approach Better Than The Plantar Approach For Plantar Plate Repair?

Yes.

These authors say the dorsal approach is superior as it can allow the surgeon to restore normal anatomy in plantar plate repair while avoiding compromise of the metatarsophalangeal joint plantarflexory mechanism, the flexor tendons and plantar fascia.  

By Lowell Weil, Jr., DPM, MBA, FACFAS, and Erin E. Klein, DPM, MS

As the plantar plate has come to the forefront of forefoot surgery as a structure that can cause both deformity and pain, we have seen an emergence of techniques to repair this structure. Currently, there are both dorsal and plantar techniques. The dorsal approach has some advantages in comparison to the plantar approach.

In order to understand the superiority of the dorsal approach to plantar plate repair, we must clearly understand the anatomy of the region.

The plantar plate is a structure that is composed largely (75 percent) of type 1 collagen.¹ The dorsal two-thirds of the plantar plate are organized in longitudinal fibers.¹ The plantar one-third of the plantar plate is composed mainly of transverse fibers that are continuous with the deep transverse intermetatarsal ligament and adjacent to the flexor tendons.¹ The plantar portion of the plantar plate receives the deep slips of the distal insertion of the plantar fascia.^1,2 The plantar plate and the deep slips of the plantar fascia compose the mechanism by which plantarflexion occurs at the metatarsophalangeal joint (MPJ).^1,2 There is no direct flexor tendon attachment at that level. Therefore, if plantarflexion is to occur at the lesser MPJ, the plantar fascia and the plantar plate must be intact.

In addition to the plantar plate, the collateral ligaments are important for lesser MPJ stability. There are two distinct collateral ligaments that originate from the tubercle on either side of the lesser metatarsal head. The proper collateral ligament arises from the dorsal/superior aspect of the tubercle and courses distal and plantar to insert at the base of the proximal phalanx.^2,3 The accessory collateral ligament originates from the inferior portion of the tubercle and courses plantarly to insert at the lateral border of the plantar plate.^2,3 Accordingly, the medial and lateral borders of the plantar plate are critically important to stability as the deep transverse intermetatarsal ligament also attaches here. A recent cadaveric study confirmed Stainsby’s finding that the deep transverse intermetatarsal ligament is an important factor in MPJ stability.^4,5

How The Dorsal Approach Facilitates Improved Visualization Of Pathology
The dorsal approach to the plantar plate is a far superior approach to plantar plate repair because it allows for restoration of normal anatomy. One can repair the plantar plate and collateral ligaments while avoiding compromise of the MPJ plantarflexory mechanism, the flexor tendons and plantar fascia.

Plantar plate pathology can occur in any part of the plantar plate. It has been our experience that many of the lower grade tears and the subtle tears occur in the dorsal aspect of the plantar plate. Surgeons would either miss these completely or not be able to visualize them adequately from the plantar approach.

Higher grade tears, particularly complete tears, would be theoretically visible from either the dorsal or plantar approach. However, it has been our experience that tears from the base of the proximal phalanx are often severe but not entirely complete. This would not be visible from the plantar aspect of the joint as the plantar most fibers of the plantar plate are the ones that remain intact.

There are other pathologies that will destabilize the MPJ, namely collateral ligament pathology. This pathology would be very difficult to see from the plantar approach. These ligaments are important to lesser MPJ stability and one should repair them if there is any indication that there might be pathology present. The accessory collateral ligament attaches directly to the plantar plate and this would be very difficult to visualize from the plantar approach.

Emphasizing A Quicker Return Of Motion And Strength
Having the patient regain motion and strength are two critically important parts of the postoperative protocol for this procedure. A toe with a plantar plate injury will start to change position and usually starts to sit a bit off the floor with slight angulation in the transverse plane. Being in that position for elongated periods of time can lead to compensatory alterations in the tension and strength of the dorsal tissue.

Therefore, after restoring the joint’s anatomy, one needs to restore proper motion and strength as well. Strengthening of the intrinsic muscles is important. More important, however, is restoring the plantarflexory mechanism at the lesser MPJ. As we mentioned above, plantarflexion at the MPJ is indirect and requires that the plantar fascia, flexor tendons and pulley mechanism are all intact. The dorsal approach allows these structures to remain intact and does not compromise the pulley mechanism by sectioning the plantar fascia as most plantar approaches do. Patients who have had the dorsal approach will be able to start mobilizing these tissues approximately a week after surgery rather than having to wait for the skin to heal prior to mobilization.

Finally, if an osteotomy is necessary, the dorsal approach enables the surgeon to repair the plantar plate and the collateral ligaments through the same incision. With a plantar incision, if collateral ligament repair or an osteotomy are necessary, a second incision is required. This may, over time, lead to more scarring and a slightly elongated postoperative recovery.

In Summary
The dorsal approach to the plantar plate repair is the superior approach because it allows visualization and repair of the plantar plate (both subtle and extensive tears), the collateral ligaments and metatarsal deformity. The dorsal repair also more adequately restores normal anatomy to the lesser MPJ, which will hopefully restore function as well.

Dr. Weil is the President and Fellowship Director of the Weil Foot, Ankle and Orthopedic Institute. Dr. Weil is a Fellow of the American College of Foot and Ankle Surgeons. He also serves as the Editor of Foot and Ankle Specialist.

Dr. Klein is the Reconstructive Foot and Ankle Surgical Fellow at the Weil Foot, Ankle and Orthopedic Institute.

References

1. Johnston R, Smith J, Daniels T. The plantar plate of the lesser toes: an anatomical study in human cadavers. Foot Ankle Int. 1994; 15(5):276-82.
2. Deland J, Lee K, Sobel M, DiCarlo E. Anatomy of the plantar plate and its attachments in the lesser metatarsal phalangeal joint. Foot Ankle Int. 1995; 16(8):480-9.
3. Sarafian S, Topouzian L. Anatomy and physiology of the extensor apparatus of the toes. J Bone Joint Surg Am. 1969; 51(4):669-79.
4. Stainsby G. Pathological anatomy and dynamic effect of the displaced plantar plate and the importance of the integrity of the plantar plate-deep transverse metatarsal ligament tie-bar. Ann R Coll Surg Engl. 1997; 79(1):58-68.
5. Wang B, Guss A, Chalayon O, et al. Deep transverse metatarsal ligament and static stability of lesser metatarsophalangeal joints: a cadaveric study. Foot Ankle Int. 2015;36(5):573-8.
6. Trnka H, Nyska M, Parks P, Myerson M. Dorsiflexion contracture after the Weil osteotomy: results of a cadaver study and three dimensional analysis. Foot Ankle Int. 2001; 22(1):47-50.

No.

Noting the variety of plantar plate tears, this author says the dorsal approach can be problematic in cases of isolated plantar plate repair, has limitations with the treatment of ruptures and prevents adequate debridement of plantar plate rupture sites.

By Neal Blitz, DPM, FACFAS

Plantar plate pathology is probably the most challenging surgical problem that we treat within the foot. This pathology can be difficult to diagnose and its treatment algorithms are not well defined. Moreover, outcome studies are lacking because there is a wide spectrum of plantar plate pathology (which varies from case to case) and treatments may involve a variety of surgical procedures, some of which are focal to the plantar plate and others that are focal to the overall balance of the foot.  

Recently, there has been much interest in plantar plate repair from the dorsal approach as opposed to the traditional plantar approach and controversy as to which method is “the best plantar plate repair” procedure.¹ The most important question to ask is if we should repair the plantar plate at all rather than questioning the specific approach. We should also ask which method is the best to accomplish a stable repair in conjunction with the other procedures necessary to balance the foot.  

Before this discussion extends to the method of repair, it is important to understand that not all plantar plate tears are the same. A tear could be small and linear, of moderate size and zigzag in orientation, or large and stellate. The tear could be central within the plantar plate or a complete avulsion of the plantar plate directly off the bone. Moreover, a diagnosis of plantar plate injury says nothing of the stability of the second toe, its position, the presence of a hammertoe and/or a bunion. Small tears may not cause instability whereas large tears usually do. Small tears may stay small or they may further extend to the larger tear with instability. The surgeon needs to take all of these factors into account when considering plantar plate repair.  

Emphasizing Direct Access For Primary Repair
Historically, plantar plate repair has involved a plantar incisional approach because it provided direct access and visualization for primary repair of the ligament. With this approach, one can perform all tear variations of plantar plate repair from simple rents to complex stellate tears. The plantar approach also allows for easy access to the plantar base of the proximal phalanx for direct reattachment of the plantar plate when one completely avulses the ligament completely off the base of the phalanx, and when a bone anchor reattachment is indicated. The plantar approach has had criticism for its potential to create a painful plantar scar, something that I have not witnessed as long as one curves the incision to avoid a direct pressure spot, and avoids over-dissection of the area. ²

Key Drawbacks Of The Dorsal Approach
The dorsal plantar plate approach is indeed a novel approach because modern ingenuity and instrumentation now allow access to the plantar plate by distracting the toe and/or shortening the second metatarsal. In most cases, the dorsal approach requires a shortening osteotomy of the second metatarsal (i.e., Weil osteotomy) for proper visualization and ability to fixate the ligament. The use of specialized instruments enables surgeons to grab and thread sutures through the plantar plate, and allows them to secure sutures to the second toe via drill holes in the bone.  

A major downside of the dorsal approach is the need for the Weil osteotomy for purely plantar plate repair. Since the Weil osteotomy is associated with a real risk of causing a floating toe, do not use it lightly in the context of isolated plantar plate repair.³ A floating toe can be as problematic or possibly more problematic than the symptoms of the plantar plate issue. If the case calls for second metatarsal shortening as part of the overall procedures to balance the foot, then a Weil osteotomy may be indicated anyhow and serves a dual purpose. Performing metatarsal osteotomies in the face of a relatively normal metatarsal parabola for a “small” plantar plate tear with an equivocal Lachman test may be more than necessary.

Another limitation of the dorsal approach is the limited ability to deal with a variety of ruptures. For those experienced in plantar plate repair, tear morphology is quite variable and often preoperative imaging (i.e., magnetic resonance imaging) does not particularly correlate with intraoperative appearance. Accordingly, surgeons could be expecting rather straightforward tears only to find diseased, complex tears. These tears may present a challenge to fix dorsally whereas a plantar approach gives the surgeon direct access.  

Another important limitation of the dorsal approach is the inability to debride the plantar plate rupture site adequately. It is well known that the plantar plate is a relatively avascular ligamentous structure. In chronic cases, the ends of the rupture site may have degenerated, requiring debridement. Additionally, the ends of the plantar plate may need debridement to “freshen up” the edges to promote vascularity and healing.  
Lastly, tears are often not anatomically simple, meaning that they may run diagonally, be “T” shaped and/or be associated with overall attenuation of the plantar plate. There may also be ligament loss of the plantar plate. In these cases, a block resection of the plantar plate ligament may be required to organize the tear, which may be nearly impossible in some cases with a dorsal approach. When doing a block resection of the plantar plate, one may perform some angulation of the repair to help treat minor transverse plane issues.  

In Conclusion
In clinical practice, I have found that plantar plate ruptures do not always require surgical repair. Much of the decision making depends on the chronicity of the plantar plate tear and whether a hammertoe has formed. The patients who seem to respond the best are those who have had treatment early and have flexible toes without a transverse plane deformity. Once hammertoe repair, with arthoplasty or arthrodesis, is necessary with a semi-rigid metatarsophalangeal joint (MPJ) contracture, there is less need to perform plantar plate repair. In these cases, one releases the MPJ and pinning often creates enough scarring to stabilize the toe. If a second metatarsal osteotomy is necessary, one can perform a plantar plate repair but it may not be necessary clinically.  

In my current practice, I have found the best treatment for plantar plate tears is to balance the foot and remove the biomechanical forces that may have contributed to the tear in the first place. This often requires medial column stabilization, gastroc recession, hammertoe repair and/or parabola restoration.

It is my hope that this article encourages you to look for the need for plantar plate repair and consider the overall function of the foot rather than the surgical approach.

Dr. Blitz, the creator of the Bunionplasty^® procedure, is in private practice in both Midtown Manhattan, New York and Beverly Hills, Calif. He is board-certified by the American Board of Foot and Ankle Surgery, and is a Fellow of the American College of Foot and Ankle Surgeons. To learn more about minimally invasive bunion surgery, visit www.bunionplasty.com.

To learn more about plantar plate repair surgery by Dr. Blitz, please visit his website at www.DrNealBlitz.com .

References

1. Watson DS, Reid DY, Frerichs TL. Dorsal approach for plantar plate repair with Weil osteotomy: operative technique. Foot Ankle Int. 2014; 35(7):730-9.
2. Blitz NM, Ford LA, Christensen JC. Plantar plate repair of the second metatarsophalangeal joint: technique and tips. J Foot Ankle Surg. 2004; 43(4):266-70.
3. Migues A, Slullitel G, Bilbao F, Carrasco M, Solari G. Floating-toe deformity as a complication of the Weil osteotomy. Foot Ankle Int. 2004; 25(9):609-13.