Innovations and renewed interest emerge regarding Lapidus bunion correction
Bunion correction remains a challenge for orthopedic foot and ankle surgeons given the stubbornly high rates of recurrence seen for the many procedures currently used.
The recurrence rates after treatment of bunion correction have driven efforts to innovate the surgical treatment of hallux valgus for decades. We have seen surgeons report their results using distal osteotomies, proximal osteotomies and everything in between (Scarf osteotomies).
Sigvard T. Hansen Jr., MD, notably advocated for a different approach that used the Lapidus first tarsometatarsal (TMT) fusion with the goal of decreasing recurrence that he felt came from generalized laxity. There has been a recent resurgence of interest in this procedure with the marketing of new instrumentation systems that share the goal of making the Lapidus bunion correction technique more precise and predictable. This article includes insights on these techniques from Scott J. Ellis, MD, and A. Holly Johnson, MD, who discuss some of the rationale, technical tips and remaining challenges of these innovative approaches to the Lapidus procedure.
- Nelson F. SooHoo, MD
- Nelson F. SooHoo, MD
- Santa Monica, California
- Scott J. Ellis, MD
- New York
- A. Holly Johnson, MD
- New York
Scott J. Ellis, MD: One factor has been the emergence of weight-bearing CT, which has opened our eyes to the role of sesamoid rotation and pronation of the first metatarsal (MT) (Figure 1). Other types of correction do not address rotation as effectively, which may contribute to recurrence.
A. Holly Johnson, MD: The instrumentation also helps make the surgery more predictable and may be especially helpful to someone starting to learn the Lapidus procedure.
SooHoo: Tell me a bit about the rationale and development of new instrumentation, such as Lapiplasty 3D Bunion Correction (Treace Medical Concepts) and LapiFuse Bunion Procedure (Wright Medical Group).
Ellis: The instrumentation may make the operation more predictable by guiding the surgeon in terms of the cuts. The Lapiplasty 3D bunion correction may make holding the reduction in all planes easier and aid in dialing in the rotation correction (Figure 2) In addition, the hardware for these systems is stable enough to allow for earlier weight-bearing.
Johnson: I agree with Scott, but believe an experienced surgeon can achieve equal results without a cumbersome jig through a large approach. I have been adapting minimally invasive techniques to the Lapidus procedure and feel I can correct the same deformities predictably. Through a percutaneous approach medially, I remove the cartilage from the joint using a 3.1-mm x 13-mm burr (Figure 3). A surgeon unfamiliar with the burr could remove the cartilage through a 1-cm dorsal incision using a small a curette (Figure 4). The joint is flushed through small medial and dorsal incisions, removing all cartilage debris. With the burr, I then dial-in the correction I need by removing a small wedge of bone on the lateral side of the joint.
SooHoo: What are key differences in these new techniques? Is it simply that with using them the surgeon is paying closer attention to rotation?
Ellis: In general, newer instrumentation allows for a more controlled assessment of rotation to guide correction. It also gives increased ability to prepare the TMT joint using cutting jigs. In addition, fixation options are varied and give great fixation compared with traditional techniques (Figure 5). I think these advantages are particularly useful for surgeons less experienced with the Lapidus procedure.
Johnson: Percutaneous foot surgery is a new skill for most surgeons and requires dedicated time to learn and practice. However, if a surgeon was already performing an open Lapidus procedure with screw fixation, a mini-open approach should be an easy way to start. The advantages are obvious: less soft tissue stripping that leads to substantially less pain and faster healing.
SooHoo: The key part of the procedure is getting good correction of the intermetatarsal angle for the TMT fusion. Do you have any tips to share?
Johnson: I preposition my wires in the desired direction and then manually reduce the joint, correcting the deformity in all planes, while an assistant drives the wires across the joint. A pointed reduction clamp between the first and second MT can help to close down the intermetatarsal (IM) angle, as well. Some minimally invasive surgery (MIS) surgeons will place a screw between the first and second MT to help position the joint.
Ellis: Although I use the LapiFuse plates, and even if you consider using the newer bunion correction systems, I still think the best way to correct the deformity is to use your experience. I do not rely on the guides or temporary fixation. I think that taking flat cuts with slightly more lateral bone on the first MT, medial cuneiform or both is the key. This allows me to completely correct the intermetatarsal (IM) angle. I also believe that correction of the IM angle depends on proper distal balancing of the first metatarsophalangeal joint, which for me is tightening the medial capsule through a longitudinal capsulotomy and also releasing the interval between the MT and lateral sesamoid through the first webspace incision. If soft tissue holds the correction up distally, even the best of cuts will not work.
Johnson: Maybe part of the IM stability that you achieve with your correction is from the medial capsular plication. I have eliminated that aspect of the Lapidus procedure, but will add a “Lisfranc screw” (medial cuneiform to second MT) to many of my corrections. Both techniques most likely confer added correction and stability to the TMT fusion.
SooHoo: One issue I have run into is that the IM angle looks well-corrected with the clamp or device holding the alignment in position. The hardware is then placed and there is loss of correction once the clamp or other holding device is removed. Do you attribute this to intercuneiform instability or another factor? How do you deal with this issue?
Johnson: I think this is often from missed intercuneiform instability. The joint looks reduced and then with simulated weight-bearing, some correction is lost. In these cases, I will add a “Lisfranc screw” from the medial cuneiform into the base of the second MT while I hold a reduction clamp in the same trajectory. You could also add a screw from the base of the first MT into the middle cuneiform.
Ellis: I think that loss of correction generally occurs in the first few months after surgery and is due to not having the IM angle perfect at the time of surgery or not having obtained proper soft tissue balance distally. I also routinely take a small wafer of bone off the lateral aspect of the first MT base and excise the soft tissue and take some bone off the base of the medial aspect of the second MT, which allows me to translate the first MT closer to the second MT. It allows me to more closely approximate the first and second MTs. It might also allow for healing across that junction even though I never have placed a screw across it. I find that a screw from the first MT base to the middle cuneiform helps me maintain the position of the first MT and probably avoids intercuneiform instability.
SooHoo: Do you think surgeons might completely avoid medial exostectomy in some cases given the correction of the first MT position?
Johnson: Yes, this might be a possibility in younger patients with less deformity. I perform a percutaneous medial eminence resection with a burr to avoid any capsular approach (Figure 6). I do not believe capsulorraphy contributes to the correction long term (Figure 7).
Ellis: I like the medial eminence incision to have the ability to tighten the capsule, which helps also reduce the sesamoids and gives a bleeding surface for the capsule to attach. However, this does probably create more stiffness (Figure 8).
SooHoo: When do you include lateral release and how is it done?
Ellis: I always do a lateral release, but for a mild bunion, you could argue not to do it. However, the lateral release helps me free the sesamoid; I am only opening the area between the sesamoid and MT, not taking down the adductor and not releasing the capsule. The Lapidus is powerful, and you want to be careful not to overdo this.
Johnson: I agree with Scott here. When I do perform the lateral release, I do this percutaneously using a beaver blade.
SooHoo: Any comments on indications? Do you recommend this for mild bunions?
Johnson: I do not think fusing the TMT joint is always necessary and in younger patients and athletes, I try to avoid it. I have seen more recurrences with distal procedures but have also seen recurrence after Lapidus correction. Intercuneiform instability may contribute to recurrence after a Lapidus procedure.
Ellis: I think a Lapidus procedure can be indicated for any bunion because I believe the center of rotation of the deformity is at the TMT joint and the Lapidus is the best way to correct pronation of the first MT. Also, the ability to bear-weight early now makes the Lapidus procedure even more attractive.
SooHoo: How do indications and results compare with new minimally invasive distal chevron techniques?
Ellis: We do not know yet. Minimally invasive approaches still result in less swelling and probably overall quicker recovery. However, Lapidus correction now can be done with early weight-bearing as well, and corrects the deformity at the center of rotation.
Johnson: In the end, I think our data will show that MIS chevron/Akin surgery will be preferable in more mild cases and in cases without intercuneiform or TMT instability. I do not think one size fits all. Scott and I are actively working on this data however so, hopefully, we will be able to offer definitive, evidence-based guidelines soon.
- For more information:
- Scott J. Ellis, MD, is associate professor of orthopaedic surgery and A. Holly Johnson, MD, is an assistant professor of orthopaedic surgery in the department of orthopaedic foot and ankle surgery at Hospital for Special Surgery. They can be reached at 535 E. 70th St., New York, NY 10021. Ellis’ email: firstname.lastname@example.org. Johnson’s email: email@example.com.
- Nelson F. SooHoo, MD, is an Orthopedics Today Editorial Board Member and professor and residency program director in the UCLA Department of Orthopedic Surgery. He can be reached at 1250 16th St., Suite 3142, Santa Monica, CA 90404; email: firstname.lastname@example.org.