Current Concepts With Revisional Bunion Surgery

Following hallux valgus surgery, patients may end up with complications or undesirable results, including bunion recurrence, nonunion or hallux varus. This author focuses on revision bunion surgery techniques that keep the big toe joint functional and provides several case example strategies for revision surgery. Bunion surgery is not always successful. Sometimes the end result is less than optimal and revision bunion surgery may be necessary.¹ The key to revision bunion surgery is to understand what caused the “poor outcome” in the first place and provide a surgical plan to undo or revise the index operation.^2,3    “Failed bunion surgery syndrome” is a loose term that I use to describe a patient’s perspective of an unsatisfactory outcome after the initial bunionectomy. There are various reasons that a patient may consider the bunion surgery failed. Some reasons commonly include: bunion recurrence, malunion, nonunion, hallux varus, an excessively short big toe, hallux rigidus and a new onset of pain.    As surgeons, we have the full scope perspective that a poor outcome is not necessarily a failed surgery or a complication. When it comes to bunion surgery, many problems that a patient may consider a postoperative “complication” are better termed an undesirable and/or an unexpected result.    Nonetheless, revision bunion surgery can often correct a majority of the underlying causes a patient may complain about.

How To Rectify The Return Of A Bunion

Recurrence of a bunion is always a possibility, even in the best hands. However, the timeframe for a bunion to return is often many years and not months. It is my experience that bunions tend to “recur” because the index operation did not fully address the needs of that particular foot in the first place. An example of this is performing a distal osteotomy in a foot with an extremely high intermetatarsal angle and/or not addressing hypermobility properly.    When it comes to treatment, the Lapidus bunionectomy is often a go-to procedure for recurrent bunions after a distal metatarsal osteotomy.⁴ Correcting the bony malalignment (an increased intermetatarsal angle) proximally avoids a secondary bone cutting surgery distally (especially with concerns for bone vascularity) and can also address any hypermobility issues. It is also important to address any residual adductor tendon contracture between the first and second toes, and one usually performs a revision McBride procedure as well.    “Recurrence” after Lapidus is uncommon but can occur with unaddressed hypermobility in the naviculocuneiform joint. Sometimes concomitant fusion of the first metatarsal base to the second metatarsal base can address this issue.⁵    In the photo on the right, a patient had an abnormally positioned first metatarsal bone and a bunion 20 years after having a Lapidus bunionectomy with screw fixation. Complicating matters is that the first metatarsal had been shortened excessively. The revision bunion surgery involved a distraction Lapidus to lengthen the segment and laterally position the bone into a rectus position. I performed a revision capsulotomy as well as an Akin osteotomy.

Essential Pearls For Addressing Malunions

A malunion can cause several clinical problems for patients, depending on the plane of the deformity. While malunions may be multiplanar, they often involve a single plane, making the revision less complex.    Consider sagittal plane malunions in which the first ray is positioned dorsal or plantar to the plane of the lesser metatarsals. A plantarflexed metatarsal can cause sesamoiditis and/or a loss of hallux purchase. A dorsiflexed metatarsal (elevatus) can result in hallux limitus, loss of hallux purchase and/or lesser metatarsal overload. Dorsiflexed metatarsals are common with base wedge osteotomies (especially with monofilament wires) due to early walking and plastic deformation.    Elevatus is one of the easier conditions to correct, whether the index operation was an osteotomy bunionectomy or Lapidus bunionectomy. One can correct elevated distal metatarsal osteotomies with reverse wedge osteotomies (but these can create additional shortening) or opening wedge osteotomies. Surgeons need to evaluate each independently. I have found one can successfully revise elevated base osteotomies with an inferior translatory Lapidus arthrodesis. One can translate the first ray inferiorly by approximately 50 percent at the first tarsometatarsal joint. Nonetheless, the goal in each case is to get the first metatarsal head present on the ball of the foot. Sometimes concomitant lesser metatarsal osteotomies may be necessary to achieve this.    A patient had a distal metatarsal osteotomy bunionectomy (Reverdin), which resulted in a big toe that lifted off the ground (see left photo). Retrograde pressure caused sesamoiditis. The elevated toe was due to a malunion of the osteotomy where the first metatarsal head was elevated (dorsiflexed). The revision bunion surgery involved a dorsal opening wedge osteotomy to realign and plantarflex the first metatarsal head. I used a harvested autogenous bone graft for the wedge. The results of the surgery alleviated the patient’s pain and allowed the big toe to purchase the ground.

Pertinent Insights On Managing Hallux Varus

In simplest terms, hallux varus is an over-corrected bunion that results in the big toe pulling in the wrong direction, away from the foot. The cause is a muscle imbalance that may be from improper bone alignment and/or over-tightening the soft tissue, giving mechanical advantage to certain muscles.    Hallux varus, if we do not catch and treat it early, may progress to secondary problems with a contracted hallux metatarsophalangeal joint (MPJ) and/or hallux interphalangeal joint, a result that patients commonly consider a failed bunionectomy.    In regard to treatment for early postoperative hallux varus, consider capsulotomy with pinning. The presence of hallux varus early in the postoperative period justifies aggressive treatment in my opinion. If the root cause of the varus is from a bony malalignment, then revising those osteotomies or fusions may be indicated. When the bony alignment is good and the varus is possibly due to overtightening of medial structures, then a big toe joint capsulotomy (to release the abductor muscle pull) with pinning of the big toe joint in valgus or neutral position may be quite effective.    The photo above at the right shows postoperative hallux varus due to overzealous capsulorrhaphy with a Lapidus bunionectomy. The hallux is adducted and the tibial sesamoid is peaking. Revision bunion surgery involved releasing the medial capsule and pinning the big toe in valgus for four to six weeks. The final image in the sequence demonstrates resolution of the hallux varus and the tibial sesamoid is realigned beneath the first metatarsal head.    One can correct a longstanding hallux varus and spare the big toe joint as long as the articular surface of the first metatarsophalangeal joint is in good condition and joint contractures are not drastic.    Evaluate both MPJ and hallux interphalangeal joint contractures individually. One can manage a hallux interphalangeal joint flexion contracture with a hallux interphalangeal joint fusion when the joint is rigid or severe. The focus is on salvaging the function of the big toe joint.    A common root cause of hallux varus is an overcorrected intermetatarsal angle. Previous removal of a fibular sesamoid exacerbates the situation. Reverse alignment procedures (such as reverse osteotomies or Lapidus) are the mainstays of the revision. However, it is important to consider the location of previous surgery and it may be beneficial to avoid reoperation on that particular spot depending on the blood supply and quality of the bone. Accordingly, surgeons may address a previous overcorrected distal metatarsal osteotomy with a proximal metatarsal osteotomy or midfoot fusion.    One patient had a hallux varus due to an overcorrected intermetatarsal angle combined with a fibular sesamoid release (see photo at left). The index bunion surgery occurred 20 years prior to revision. The first MPJ is intact overall but the metatarsal head is cystic, and the MPJ and hallux interphalangeal joint contractures are mild. A salvage revision bunion surgery involved a Lapidus midfoot fusion with a wedge cut to adduct the first metatarsal along with a first MPJ capsulorrhaphy and reattaching the extensor digitorum brevis to the lateral base of the hallux after passing it beneath the deep transverse intermetatarsal ligament. The clinical and radiographic results demonstrate correction of the hallux varus.    In regard to a non-salvageable deformity, severe longstanding contracture often requires a joint destructive procedure, again considering each patient individually. Implant arthroplasty is generally a poor choice for hallux varus revision due the muscular imbalances, and the fusion is often the better choice for these non-salvageable cases.    Another patient had longstanding severe hallux varus due to an overcorrected intermetatarsal angle combined with a fibular sesamoidectomy (see above right photo). The MPJ and hallux interphalangeal joint demonstrated rigid contractures. The revision surgery involved a MPJ and hallux interphalangeal joint fusion, extensor lengthening and Z-plasty of the skin. Some shortening of the hallux was necessary due to the longstanding contractures. The result was a straight big toe that fit in a shoe and a stable platform for weightbearing.

Treating An Excessively Short Big Toe (Loss Of Big Toe Purchase)

It is not uncommon to have some shortening of the big toe after bunion surgery. However, some bunion procedures may result in more shortening than others. Excessive shortening can come from osteotomies and midfoot fusion procedures. Distal osteotomies can shorten through metaphyseal bone loss if one impacts the bone during translation of the capital fragment during the index operation. Sometimes troughing of the bone can lead to shortening. A midfoot fusion may shorten the first ray by about 0.5 cm although one can compensate for this by plantarflexing/translating the segment inferiorly. Over-resection and/or excessive wedging of the first metatarsocuneiform joint surfaces during a Lapidus bunionectomy can lead to excessive shortening.    A short segment may be short in comparison with the lesser metatarsal parabola or retracted within the first metatarsophalangeal joint, resulting in a joint contracture or loss of purchase of the big toe. The body will tolerate some degree of shortening and a short segment is only problematic (or pathologic) when the shortening results in pain or secondary structural problems. These include significant symptomatic loss of hallux purchase, prominent sub-first metatarsal head with pain and/or less metatarsalgia with pain and/or stress fractures.    One can treat this via distraction (Lapidus) with big toe joint capsular release. When the first metatarsal has been excessively shortened (and the big toe joint is intact), my treatment of choice typically involves adding length through a bone block distraction midfoot fusion. Surgeons may use various grafting materials. The lateral wall of the calcaneus is an excellent source for bicortical graft and depending on the patient, one can harvest grafts up to 2 cm. Of course, the surgeon can also perform various orientation osteotomies alternatively.    One patient had a failed bunion surgery (Lapidus bunionectomy), resulting in a very short first metatarsal and a big toe that could not purchase the ground as it was fixed in 45 degrees of dorsiflexion (see left photo). The revision involved bringing the first ray back out to length with a distraction Lapidus, using autogenous calcaneal bicortical bone block, in addition to a capsulotomy of the first MPJ (with temporary pinning). The revision bunion surgery was successful as the length of the first ray returned and the hallux could touch the ground and was functional.

Keys To Remediating Nonunions

Any bone cutting bunionectomy or bone fusion bunionectomy is at risk for incomplete bone healing (nonunion). One should not really consider a nonunion to be a complication. Rather, it is a known possible occurrence. Every joint fusion has a risk rate for nonunion. Studies estimate the rate of nonunion for the first tarsometatarsal joint at 0-10 percent.^5,6 There are risk factors for developing nonunion and a common one is smoking. Surgeons should weigh these risks when considering bone surgery in general.    Radiographic nonunions (or non-painful nonunions) should not require surgical intervention. Radiographic nonunions (from joint fusion) may progress onto full radiographic union one to two years after the index operation. In my practice, I have found that an electromagnetic field is very successful in attaining fusion with nonunion cases of the first tarsometatarsal joint.    Nonunions from bunion surgery commonly respond to bone grafting and stable fixation. I prefer using autologous bone, which one can harvest from the heel bone. When length is needed, one can harvest a bicortical bone block.⁷    As far as fixation goes, each case needs independent consideration. However, I find plating useful for nonunion revision in general. If the primary surgery involved screws and hardware removal occurs at the revision, then there may not be enough bony real estate to replace screws. Accordingly, plating solves that issue as the screws enter the bone tangentially. Sometimes internal bone stimulators may be useful tools, especially for patients with poor protoplasm.

In Summary

Revision bunion surgery is complex and can be successful. There are many variables that surgeons need to consider when revising a previous bunion surgery. There is no cookie cutter operation for a failed bunion surgery. Fusion of the big toe joint for revision bunion surgery should be a last resort option. Surgeons performing revision bunion surgery should focus on keeping the big toe joint functional. Fortunately, revision bunion surgery can be extremely successful for patients.    Dr. Blitz, creator of the Bunionplasty® procedure, is a Fellow of the American College of Foot and Ankle Surgeons, and is board-certified in Foot Surgery and Reconstructive Rearfoot Surgery by the American Board of Foot & Ankle Surgery. Dr. Blitz is in private practice in both Midtown Manhattan, New York, and in Beverly Hills, Calif.
To learn more about bunion surgery by Dr. Blitz, please visit www.BunionSurgeryNY.com. References 1. Lagaay PM, Hamilton GA, Ford LA, Williams ME, Rush SM, Schuberth JM. Rates of revision surgery using Chevron-Austin osteotomy, Lapidus arthrodesis, and closing base wedge osteotomy for correction of hallux valgus deformity. J Foot Ankle Surg. 2008; 47(4):267-72. 2. Duan X, Kadakia AR. Salvage of recurrence after failed surgical treatment of hallux valgus. Arch Orthop Trauma Surg. 2012; 132(4):477-85. 3. Weinraub GM, Mejia O. Revision surgery of the first ray. Clin Podiatr Med Surg. 2009; 26(1):37-45. 4. Ellington JK, Myerson MS, Coetzee JC, Stone RM. The use of the Lapidus procedure for recurrent hallux valgus. Foot Ankle Int. 2011; 32(7):674-80. 5. Blitz NM. The versatility of the Lapidus arthrodesis. Clin Podiatr Med Surg. 2009; 26(3):427-41. 6. Blitz NM, Lee T, Williams K, Barkan H, DiDimenico LA. Early weight bearing after modified lapidus arthodesis: a multicenter review of 80 cases. J Foot Ankle Surg. 2010; 49(4):357-62. 7. Hamilton GA, Mullins S, Schuberth JM, Rush SM, Ford L. Revision lapidus arthrodesis: rate of union in 17 cases. J Foot Ankle Surg. 2007; 46(6):447-50.