Why The Lapidus Bunionectomy Is The Best Procedure For Severe Bunions

The potential for safe early weightbearing has made the Lapidus bunionectomy a viable choice for correction of severe hallux valgus. Accordingly, this author discusses eight key advantages of this procedure over other surgical options for this deformity.

Now that early weightbearing after the Lapidus procedure is a mainstream bunionectomy protocol, surgeons can more comfortably consider a Lapidus for severe bunions since they can mobilize the patient quicker.1-13

   While the Lapidus is ideal for large bunions by correcting the entire alignment of the first ray, surgeons (and patients for that matter) have previously chosen other bunionectomies purely for the ability to mobilize postoperatively. In the past several years, literature has emerged that demonstrates that Lapidus bunionectomy patients can ambulate after their surgery while achieving healing rates equivalent (or superior) to other procedures.1-13

   When it comes to large and severe bunions, the surgical procedure selection is actually the same as it would be for any bunion. The options include: fusion of the big toe joint, distal first metatarsal osteotomy, base wedge osteotomy, Lapidus procedure, Keller arthroplasty and big toe joint replacement. However, some procedures are more appropriate than others. Selecting the proper procedure for your patient is where the challenge lies with the large and severe bunion.

What Are The Advantages Of The Lapidus Procedure?

The Lapidus procedure is a highly versatile bunionectomy and has eight important advantages in comparison to a variety of other potential surgeries.14

   1. Correction of the deformity at the apex. Realigning the structural deformity of the foot by physically placing the metatarsal into its native position (near parallel) to the second metatarsal restores the foot to a more “normal” anatomic alignment. This also allows for realignment of the big toe joint subluxation. While distal metatarsal osteotomies may improve big toe joint alignment, they are limited in that there is a physical limit of correction with a distal osteotomy. In comparison to a Lapidus procedure, there is no correction limit based on the intermetatarsal angle. Also, a distal osteotomy creates an intrinsic metatarsal deformity to correct a deformity whereas the Lapidus does not. A base wedge osteotomy also creates an intrinsic metatarsal deformity.

   2. Preservation of big toe joint function. Sure, the Lapidus procedure involves sacrificing the first tarsometatarsal joint (through fusion) but it allows for big toe joint motion. Preservation of big toe joint motion is important as one considers patients with an active lifestyle and those who wish to wear specific shoe gear such as high heels. Obviously, fusion of a big toe joint eliminates this motion and fixes the toe position. A Keller arthroplasty does allow motion but this is “artificial” motion created by sacrificing a joint.

   Implants also provide artificial motion and require resection of a mobile joint. They are probably better indicated for significant arthritis and are not purely for bunion severity.

   3. Concomitant treatment of medial column hypermobility syndrome. If hypermobility is present (and deemed pathologic), then the Lapidus procedure offers the advantage of stabilizing the midfoot by decreasing midfoot motion. Some believe that severe bunions are the result of hypermobility and selecting procedures that do not address this may result in recurrence or secondary compensations. Though one may also address hypermobility with osteotomies, there is no current research to indicate the “best” method of surgical management. Nonetheless, the Lapidus procedure is indicated for the treatment of hypermobility.15

   4. Concomitant treatment of lesser metatarsal overload. In many clinical situations, the severe bunion is associated with lesser metatarsal overload (metatarsalgia) through an inefficient medial column (first ray). Stabilizing and realigning the first ray through a Lapidus procedure provides a stable construct to the medial column and also improves the efficiency of the peroneus longus.16 It is important to inferiorly translate (or plantarflex) the first metatarsal as part of the surgery to restore the weightbearing presence of the first metatarsal head.

   The Keller procedure is known to produce and exacerbate lesser metatarsal overload, and may be a poor procedure choice in patients who have metatarsalgia preoperatively. Implant arthroplasty carries a similar yet less infrequent postoperative lesser metatarsal overload risk, but one often must perform other procedures in conjunction to realign the first metatarsal.

   5. Avoiding elevatus plastic deformation risk. Postoperative elevatus from early weightbearing is a real risk with base wedge osteotomies. Though this occurrence was more common when wire fixation was in use, the risk still remains with screw fixation. The plastic deformation of an osteotomy site is the result of premature weightbearing causing an intrinsic remodeling of the first metatarsal. With a Lapidus, however, elevation can occur but it may occur concomitantly with fixation failure and nonunion. The elevatus with a Lapidus is extrinsic to the metatarsal and the effect of the failed fusion elevating through the nonunion site.

   6. Postoperative weightbearing. The ability for a patient to bear weight after a bunionectomy is often a deciding factor for procedure recommendation regardless of bunion size. Surgeons may make recommendations outside of specific intermetatarsal angle guidelines. Some doctors may even discourage bunion surgery altogether for the severe bunion because of a non-weightbearing protocol. Now that studies have emerged demonstrating that early weightbearing protocol healing rates are similar to that of non-weightbearing protocols, surgeons can consider the Lapidus as part of the potential surgeries when the post-op weightbearing is important.1-13

   7. Lapidus failure is often less disruptive than failure from other bunionectomies. A failed bunionectomy is always a challenge for both the surgeon and the patient. With Lapidus, failures are typically in the realm of nonunion. I believe that that nonunion is not a failure but a known potential outcome in a certain percentage of people (but that is beyond the scope of this article). Nonetheless, a painful nonunion of Lapidus is typically focal to the first tarsometatarsal joint and one can rectify this with revision and grafting. Any recurrent angular deformity is through the first tarsometatarsal joint and also undergoes repair at the revision fusion site. A failed metatarsal bunionectomy often results in an intrinsic deformity, which requires metatarsal osteotomy or a revision Lapidus to correct.

   Similarly, big toe joint fusions carry the risk of nonunion and malunion. In my experience, a nonunion of the first metatarsophalangeal joint (MPJ) is typically more symptomatic than a nonunion of the first tarsometatarsal joint. This seems to be due to the amount of load passing through the forefoot. Malunions of a first MPJ fusion can cause similar problems with that of a midfoot fusion and may require revision.

   A failed Keller or implant procedure involves a revision fusion of the first MPJ with bone block grafting, a procedure that involves a prolonged period of convalescence and non-weightbearing. These reconstructions are challenging for both patient and surgeon.

   8. Improving rearfoot alignment. Realigning and stabilizing the first ray has a realigning effect on the rearfoot as well. This is an advantage of the Lapidus. A retrospective radiographic study by Avino and collagues demonstrated radiographic improvement of the talo-first metatarsal angle.17

Key Preoperative Considerations

When considering the Lapidus bunionectomy for severe bunions, it is important to carefully evaluate the first MPJ for arthritis and the second MPJ for subluxation with overload symptoms. When these clinical conditions occur in conjunction with the severe bunion, other procedures may be needed in addition to the Lapidus to balance the foot. With end-stage problems, however, other bunionectomies may be better indicated.

   Arthrosis of the first MPJ with severe bunions is often due to malalignment, wear and tear. Of course, several degrees of arthrosis may occur depending on the severity of the bunion, the duration of the bunion and the activity level. In my clinical experience, a long first metatarsal with massive subluxation of the big toe joint results in less destructive arthrosis. This is because the first metatarsal head of the joint is not articulating anymore and therefore gets spared from biomechanical “wear.” The cartilage itself is of poorer quality because of the loss of normal mechanics of the big toe joint.

   Significant arthrosis of the big toe joint may not respond well to realignment of the joint with reconstruction. In general, my experience has demonstrated that even with the best realignment/reconstruction, the first MPJ will lose a fair amount of motion with severe bunion reconstruction so the presence of some radiographic arthrosis does not become a functional limiting factor. The biggest issue is whether the joint is supple enough to be relocated. However, end-stage arthrosis of the big toe joint (Stage IV) is best served with a joint destructive procedure of the first MPJ and this may also require a Lapidus to treat concomitant hypermobility.

   A severe subluxed second toe secondary to overload may present a challenge when considering Lapidus for the severe bunion. Lesser toe problems are well known to occur with severe bunion deformities and may originate from overload and the hallux under-riding the second toe. A severely dislocated second toe often requires a lesser metatarsal osteotomy with digital repair and, depending on the extent of the reconstruction, may require postoperative non-weightbearing. Since one can use the Lapidus with an early weightbearing program, the limiting factor for a patient to go forward with a reconstruction is the non-weightbearing component of the lesser toe reconstruction.

Initiating An Early Weightbearing Program With A Lapidus Bunionectomy

In regard to determining which patients you should allow to begin an early weightbearing program, exact guidelines have yet to be established. However, an early weightbearing program does not affect the indications for Lapidus arthrodesis.

   Patients who have an increased risk for complications should avoid early weightbearing or bear weight cautiously. Patients (such as smokers) who have an increased risk for nonunion may not be good candidates for early weightbearing but this is not an absolute contraindication. Obese patients are not great candidates for early weightbearing due to the force that can pass through the fusion site and lead to fixation failure. Do not enroll neuropathic patients in an early weightbearing program for similar reasons. Osteopenic patients with poor bone stock are also poor candidates.

   The fixation construct is extremely important when considering early weightbearing after a Lapidus bunionectomy. A construct that provides compression, resists rotation and counteracts the forces of weightbearing is important when considering the fixation method. When using screw fixation, it is best to use two screws. Surgeons have utilized a variety of techniques for screw fixation and these techniques can be categorized into long screw fixation or short screw fixation. Advocates of long screw fixation believe that longer screws provide resistance to cantilever forces. Plate fixation is also in use with a variety of plating systems. More contemporary options include specialized plating systems that are dedicated and contoured for the first tarsometatarsal joint.

   Surgeons may initiate early weightbearing protocols immediately after surgery, at the two-week visit or at four weeks postoperatively. Of course, the fixation construct plays an important role when it comes to starting early weightbearing. An advantage to waiting until the two-week visit at suture removal is that it allows for surgeons to be confident that the soft tissue envelope is healed. Surgeons should be comfortable with the Lapidus arthrodesis before initiating an early weightbearing program.

Final Thoughts

The Lapidus bunionectomy has several advantages for severe bunions in comparison to other methods in that the surgeon can preserve the big toe joint and realign the first metatarsal at the apex of the deformity.

   Since fixation techniques have improved and early weightbearing protocols have emerged, surgeons can utilize the Lapidus for severe bunions in cases in which they previously had to resort to joint destructive procedures.

   Dr. Blitz is the Chief of Foot Surgery and Associate Chairman of Orthopaedics at Bronx-Lebanon Hospital Center in New York. He is Board Certified by the American Board of Podiatric Surgery and is a Fellow of the American College of Foot and Ankle Surgeons. Dr. Blitz can be reached at nealblitz@yahoo.com, and @DrNealBlitz on Twitter.

   Disclosure: Dr. Blitz is a consultant to Orthofix, Inc., and receives royalties for the Orthofix Contours Lapidus Plating System.

References

1. 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.
2. Basile P, Cook EA, Cook JJ. Immediate weight bearing following modified lapidus arthrodesis. J Foot Ankle Surg. 2010; 49(5):459-64.
3. Sorensen MD, Hyer CF, Berlet GC. Results of lapidus arthrodesis and locked plating with early weight bearing. Foot Ankle Spec. 2009; 2(5):227-33.
4. Menke CR, McGlamry MC, Camasta CA. Lapidus arthrodesis with a single lag screw and a locking H-plate. J Foot Ankle Surg. 2011; 50(4):377-82.
5. DeVries JG, Granata JD, Hyer CF. Fixation of first tarsometatarsal arthrodesis: a retrospective comparative cohort of two techniques. Foot Ankle Int. 2011; 32(2):158-62.
6. Klos K, Gueorguiev B, Muckley T, Frober R, Hofmann GO, Schwieger K, Windolf M. Stability of medial locking plate and compression screw versus two crossed screws for lapidus arthrodesis. Foot Ankle Int. 2010; 31(2):158-63.
7. Kazzaz S, Singh D. Postoperative cast necessity after a lapidus arthrodesis. Foot Ankle Int. 2009; 30(8):746-51.
8. Saxena A, Nguyen A, Nelsen E. Lapidus bunionectomy: Early evaluation of crossed lag screws versus locking plate with plantar lag screw. J Foot Ankle Surg. 2009; 48(2):170-9.
9. Blitz NM. Early weightbearing of the Lapidus: is it possible? Podiatry Today. 2004; 17(8):46-52.
10. Bednarz PA, Manoli A 2nd. Modified Lapidus procedure for the treatment of hypermobile hallux valgus. Foot Ankle Int. 21(10):816-21, 2000.
11. Myerson M, Allon S, McGarvey W. Metatarsocuneiform arthrodesis for management of hallux valgus and metatarsus primus varus. Foot Ankle. 1992; 13(3):107-115.
12. Sangeorzan B, Hansen, S. Modified Lapidus procedure for hallux valgus. Foot Ankle. 1989; 9(6):262-266.
13. Clark HR, Veith RG, Hansen ST Jr. Adolescent bunions treated by the modified Lapidus procedure. Bull Hosp Jt Dis Orthop Inst. 1987; 47(2):109-22.
14. Blitz NM. The versatility of the Lapidus arthrodesis. Clin Podiatr Med Surg. 2009; 26(3):427-41.
15. Blitz NM. Current concepts in medial column hypermobility. Podiatry Today. 2005; 18(6):68-79.
16. Bierman RA, Christensen JC, Johnson CH. Biomechanics of the first ray. Part III. Consequences of Lapidus arthrodesis on peroneus longus function: a three-dimensional kinematic analysis in a cadaver model. J Foot Ankle Surg. 2001; 40(3):125-31.
17. Avino A, Patel S, Hamilton GA, Ford LA. The effect of the Lapidus arthrodesis on the medial longitudinal arch: a radiographic review. J Foot Ankle Surg. 2008; 47(6):510-4.

   For further reading, see “Early Weightbearing Of The Lapidus: Is It Possible?” in the August 2004 issue of Podiatry Today.

   Dr. Blitz also writes a blog for Podiatry Today. For recent blogs, visit https://bit.ly/rJ5nnq .