Addressing Plantar Plate Injury: Why a Complete Toolkit Is the Key

Plantar plate injuries are among the most troubling issues to treat properly in my practice. They are complicated, difficult, require great attention to detail and often require me to make decisions at the time of surgery that I did not originally anticipate.  

I have begun to consider how to treat these conditions systematically so I can discuss the potential treatment needs and choices with patients in order to consent them properly, avoid surprises, and make them aware of the options prior to surgery. To accomplish this, I have come up with different categories of plantar plate injury and treatment requirements, which helps me put the surgical foot in a category and then put procedure requirements into those same categories.

A Guide to the Patient Workup and Planning

I divide plantar plate injuries according to level of damage, mainly dealing with the position of the toe. The more deviated and dorsally dislocated the toe, the more difficult the correction and the higher the category I place it in.

The workup of patients with suspected plantar plate injury is a critical part of the analysis of the injury and the needs for repair. The examination should include both non-weight-bearing and weight-bearing analysis of the foot and position. I find there is often an associated hypermobility of the foot and, in many cases, hallux valgus. Decisions on the type of hallux valgus correction and procedure are an important adjunct to consider, and therefore one should check for hypermobility. Check the position of the injured toe with the patient both weight-bearing and seated. Often, with weight-bearing, the toe shifts far more out of rectus alignment than while seated. Dorsal drawer testing of the toe and any associated pain and laxity can help in identification of the level of plantar plate injury and necessary repair techniques. In cases of significant metatarsophalangeal joint (MTPJ) dislocation, important parts of the exam include checking for crepitus with motion and checking if the toe can be relocated within the joint.

Taking weight-bearing foot radiographs is an essential part of the workup, as they show the anatomy of the foot, length of the metatarsals and parabola, and signs of both arthritis and joint dislocation. Magnetic resonance imaging (MRI) is also a mainstay for preoperative planning for plantar plate repairs. Check the condition of the plantar plate on these images, including the amount of tear and degree of tear. Also check the metatarsal head for arthritic changes, articular cartilage damage, and possible avascular changes.

Nonsurgical alternatives for plantar plate injury include taping of the toe to the neighboring toe, taping the toe in a plantar position across the MTPJ, orthotic use, and rigid-sole shoes. In my experience, orthotics should have a metatarsal pad and a cutout of the associated metatarsal head to reduce pressure on the damaged plantar plate. I avoid cortisone injection into plantar plate injuries as this may result in weakening and further tear. I often use a compounded cream of a nonsteroidal anti-inflammatory, gabapentin, lidocaine, and associated products to try to calm down the inflammation and pain in the MTPJ. I have extensively used both platelet-rich plasma and amniotic fluid injections to help with plantar plate repair and potential healing for the injured region. In such cases, I will perform the desired injection, strap the toe in a rectus plantarflexed position and use a rigid-sole shoe or walker boot to reduce pressure on the plantar plate during healing. In early cases of injury without dramatic drift of the toe, these injections have been very successful in healing the area without surgery.

Surgical Options for Plantar Plate Injuries at Various Levels

Following a thorough workup and conservative alternative attempts, I discuss surgical options with the patient and try to select procedure(s) based on the level of damage.

Level 1 plantar plate and capsular injury involves a mild hammertoe, no medial or lateral deviation and a mild dorsal drawer finding. In level 1 cases, I find that the procedures mainly require realignment without much plantar plate repair or angular correction. The main procedures I used in these cases are a hammertoe correction, preferably with toe fusion, and an associated metatarsal shortening osteotomy. I may augment the surgery with a platelet-rich plasma injection of the plantar plate region but MRI findings in these cases show minimal-to-no tear and therefore realignment is sufficient.

Level 2 plantar plate and capsular injury has deviation of the toe medial or lateral, hammering of the toe, a laxity of the plantar plate with pain to dorsal drawer testing but the associated toe is not over or under the other toes. There is a mild deviation that may abut the adjoining toe. In such cases, I note that correction will require hammertoe fusion, metatarsal osteotomy, including medial or lateral shift of the metatarsal to help with toe alignment, and possible plantar plate repair. In such cases, I find the plantar plate is often only partially torn and there is only a partial repair necessary.

I prefer to use the Hat Trick system (Smith + Nephew) for these patients because I can use a bilateral kit but perform a unilateral repair. I will pass sutures only through the associated tear region of the plantar plate. For example, the most common region will be the lateral plantar plate of the second toe. I will place a suture through the lateral plantar plate tear region, pass the suture from lateral to medial through the proximal phalanx and the secure the suture with the provided polyetheretherketone (PEEK)-threaded K-wire through the drill hole. In this way I can correct the medial deviation of the second toe. The exact steps I use are: preparation of the second toe for fusion, second metatarsal osteotomy with a medial shift of the head (for example to move the second toe more lateral), repair of the lateral plantar plate, permanent fixation of the second metatarsal head with a screw, stabilization of the second toe hammertoe with an implant, and angular correction of the second toe shifted alignment with PEEK K-wire stabilization of the sutures placed in the plantar plate. It’s a lot of steps for a fairly simple injury

Level 3 plantar plate and capsular injury has medial or lateral deviation of the toe, hammering of the toe, severe laxity with possible mild reducible dislocation of the toe, and possible toe position over or under the adjacent toe. In such cases, the procedure will require everything in level 2 plus a possible complete repair of the plantar plate versus flexor tendon transfer to the toe if the plantar plate is of insufficient quality.

Level 4 is a complete toe dislocation, chronic in nature with or without dislocation and contour changes to the metatarsal head or phalanx base. In such cases, hammertoe correction with flexor tendon transfer is the mainstay of the procedures. The metatarsal head will require either metatarsal osteotomy or, more commonly, metatarsal head resection due to the severe damage in the metatarsal head contour and arthritic changes. I have found metatarsal head resection along with hammertoe correction may be sufficient to correct the problem but, in certain cases, a flexor transfer may be necessary to stabilize the toe in a rectus position. I tend not to use a K-wire across the MTPJ with my plantar plate procedures including flexor transfers but I do like a K-wire in patients with metatarsal head resection as it help to fibrose in the empty metatarsal head region and this adds stability and improves alignment of the toe position.

In Conclusion

With proper planning, categorization and work up of plantar plate injuries, I find that the success in repair of this injury is very high and often leads to happy patients who can return to full activity without pain and restrictions. I hope the level of injury analysis above helps with surgical decisions and planning.

Dr. Baravarian is Director and Fellowship Director at University Foot and Ankle Institute.