Point-Counterpoint: Has The Medial Double Arthrodesis Supplanted The Triple Arthrodesis?

Yes.

Offering insights from the literature and their experience, these authors cite several advantages of the medial double arthrodesis, including better visualization leading to easier reduction of the deformity and reduced complication risk.   

By Jeffrey E. McAlister, DPM, FACFAS, and Chad Seidenstricker, DPM, AACFAS

The medial double arthrodesis (talonavicular and subtalar joints) has become a viable alternative to triple arthrodesis for rigid and/or severe pes planovalgus deformity. It offers many advantages including improved visualization, avoidance of calcaneocuboid joint non-union and minimal risk to medial neurovascular structures with direct visualization from the medial side, and a natural tendency to resect more bone medially, which helps reduce the laterally subluxed subtalar joint. The medial double arthrodesis also facilitates decreased operative time by limiting the approach to a single incision and decreased operative costs.

While there may be instances in which a combined medial and lateral or an isolated lateral incision may be indicated, the utilitarian medial double arthrodesis has become the best option when addressing severe and/or rigid pes planovalgus.

What The Literature Reveals About The Medial Approach To Triple Arthrodesis

Our foot and ankle literature is stout with studies assessing medial double and triple arthrodeses. The following is a brief review of the literature on the medial double arthrodesis.
Astion and colleagues’ landmark cadaveric study examined the effect of isolated hindfoot arthrodesis on hindfoot motion.¹ The authors demonstrated that talonavicular joint arthrodesis limits motion of the subtalar joint and calcaneocuboid joint to 2 degrees. O’Malley and coworkers also performed talonavicular and subtalar joint fusions in a cadaveric study, demonstrating equivalent reduction of deformity as a triple arthrodesis with sparing of the calcaneocuboid joint.²  

Jeng and colleagues first described the medial approach for the triple arthrodesis.³ While the authors attempted a “complete” triple fusion, the concept of a medial approach to the transverse tarsal joint and subtalar joint was an important concept they introduced. They advocated for a medial approach to avoid potential wound healing complications. In the severe fixed pes planus, the lateral integument is contracted. When one opens the lateral side and then reduces the valgus deformity, the contracted skin and underlying tissue are under additional tension, and subject to wound breakdown. The authors’ pearls for the procedure included percutaneous release of the contracted peroneals and aggressive capsuloligamentous release of the subtalar joint (and calcaneocuboid joint if included in the fusion mass).

In a retrospective review looking at the use of the single medial incision approach to triple arthrodesis, Jeng and colleagues evaluated 17 patients (average age of 59) with rigid hindfoot valgus deformity at a mean follow-up of 3.5 years (minimum one year).³ The average AP talo-first metatarsal angle improved 24 degrees (from 30 degrees preoperatively to 6 degrees postoperatively). The single downside was non-union of the calcaneocuboid joint, occurring in two of 17 patients. In a subsequent cadaver study, Jeng and coworkers demonstrated that surgeons could adequately resect 91 percent of the talonavicular and subtalar joint surfaces through the isolated medial approach to triple arthrodesis.⁴

Sammarco and colleagues conducted a retrospective study of 16 patients who had hindfoot malalignment without primary involvement of the calcaneocuboid joint.⁵ After concurrent subtalar joint and talonavicular joint fusions (sparing the calcaneocuboid joint), the patients had a mean improvement in the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score from 44.7 preoperatively to 77.0 postoperatively. All patients were satisfied and would have the procedure performed again under similar circumstances.

Emerging Insights On The Single Medial Incision Approach To Double Arthrodesis

Putting these two concepts together (medial approach and double fusion sparing of the calcaneocuboid joint), several researchers evaluated the single medial incision double arthrodesis. Lee advocated for the medial approach double arthrodesis.⁶ He cited no risk of lateral wound dehiscence, no risk of calcaneocuboid joint non-union, less operating time, a decreased chance of undercorrection and, subsequently, residual deformity. Lee also noted that with a 30-month follow-up of this procedure, none of his patients developed calcaneocuboid joint pain and described a natural diastasis that occurs at the calcaneocuboid joint with adequate reduction of the pes planovalgus through the talonavicular and subtalar joint fusion.

Knupp and colleagues retrospectively evaluated 32 feet (30 patients) who had single, medial incision talonavicular and subtalar joint fusion for severe pes planovalgus.⁷ Fusion occurred in all feet at a mean of 13 weeks postoperatively. All standard radiographic parameters improved aside from calcaneal pitch (mean 18 degrees pre- and postoperatively). No wound healing complications occurred.

In 2009, Brillhault and coworkers retrospectively evaluated 14 feet in 11 patients that had a single-medial incision double arthrodesis for rigid flatfoot and laterally deficient skin with a 21.5-month follow-up.8 They had no wound healing complications and no patients developed a painful calcaneocuboid joint following the procedure. Radiographic improvement was apparent in the AP talocalcaneal angle (38.5 degrees to 7 degrees postoperatively), Meary’s angle (21 degrees to 0 degrees postoperatively) and hindfoot alignment (18 degrees to 7.5 degrees postoperatively).

In a 2010 retrospective study, Weinraub and colleagues evaluated 45 patients following single incision medial double arthrodesis with 27 of the patients having a diagnosis of posterior tibial tendon dysfunction.⁹ They noted easy translation of the calcaneus medially through this approach. They had no non-unions but one case of a painful calcaneocuboid joint and one case of incision dehiscence. The mean surgical time was 87 minutes and the study authors noted the cost savings by avoiding the lateral incisional approach (no additional fixation and no bone graft, which is often required to prevent shortening of the lateral column through the calcaneocuboid joint).

In their retrospective review, Philippot and coworkers evaluated 14 patients following a single incision medial double arthrodesis with an average follow-up of 20.6 months.¹⁰ The study authors noted a 10-degree improvement in hindfoot valgus (from 20 to 10 degrees) and a 10-degree correction of the medial arch (angle of Djian). Despite slight undercorrection radiographically, clinical results were satisfactory regarding pain relief and posture, and hindfoot alignment. There were no wound healing complications. Patients also had 100 percent successful radiographic and clinical fusion.

Anand and colleagues performed a retrospective study on the use of a single-incision medial approach for double arthrodesis of the hindfoot in 18 feet with posterior tibial tendon dysfunction.¹¹ The authors found a 78 percent patient satisfaction rate and no wound complications. They also noted correction of the AP talocalcaneal angle from 28.9 to 18.3 degrees and Meary’s angle correction from 23.9 to 11.1 degrees. The union rate was 89 percent with 16 of 18 feet achieving radiographic and clinical union of both fusion sites.

Are Double Arthrodesis Patients At Risk For Post-Op Ankle Valgus?

Hyer and coworkers performed the only comparative study evaluating the development of postoperative ankle valgus after medial double arthrodesis in comparison with triple arthrodesis.¹² The authors found 54 percent of triple arthrodesis patients had increased ankle valgus tilt postoperatively in comparison to 25 percent in the medial double arthrodesis cohort. The follow-up was shorter in the medial double arthrodesis group (8.8 months versus 17.5 months). However, this is the only comparative data evaluating this potential sequela.

Whether one is performing a medial double arthrodesis or a classic triple arthrodesis, fusion involving the talonavicular joint can be problematic in any hindfoot fusion. This locks the hindfoot, placing increased stress on both the deltoid and the syndesmosis. The rigid hindfoot lever arm is no longer able to compensate and dissipate forces through the hindfoot and forefoot, and valgus stress is instead levered to the incapable deltoid and syndesmosis.

The point of this discussion involving possible ankle valgus is that this complication is multifactorial and the only evidence evaluating its occurrence finds the medial double arthrodesis less likely to cause this complication.

In Conclusion

These studies support the single incision medial double arthrodesis for severe flatfoot deformity. This approach offers an adequate reduction of severe deformity when evaluating any of the standard radiographic parameters clinicians typically use to evaluate flatfoot.^7,8,11 Only Philippot and coworkers found residual radiographic deformity in their patients, but all patients had clinical alignment improvement and were satisfied with the outcome.¹⁰ The union rate of the talonavicular joint and subtalar joint is nearly 100 percent in the retrospective case series evaluated in five studies.^7-11

In my opinion, the advantages of this technique are improved visualization allowing more aggressive medial joint surface resection, permitting easier reduction of deformity (i.e. medial translation of the calcaneus underneath the talus). The calcaneocuboid joint has not been symptomatic postoperatively in these cases, likely due to natural diastasis along the lateral column by adequately reducing the medial column. Additional non-unions are negated by avoidance of the calcaneocuboid joint. There was a 0.8 percent (1 of 123 patients) incidence of incisional dehiscence in the aforementioned single-medial incision double arthrodesis studies.^7-11 The authors of these studies have also seen a low incidence of wound healing complications.

Once they are familiar with this approach, surgeons should expect similarly good outcomes with regard to reduction of deformity, high union rate, good patient satisfaction, low risk for non-union and low incidence for residual or new onset pain along the lateral column while avoiding potential non-unions of the calcaneocuboid joint. This approach allows for shorter operative time and less fixation, which reduces cost as an added benefit.9 The concern for increased risk of ankle valgus as a postoperative sequela of the medial double arthrodesis is currently unsubstantiated in the literature.

Dr. McAlister is an attending at The CORE Institute in Phoenix, AZ. He is a board-certified, fellowship-trained foot and ankle surgeon.

Dr. Seidenstricker is a current fellow at the CORE Foot and Ankle Advanced Reconstruction Fellowship in Phoenix.

References
1.     Astion JD, Deland JT, Otis JC, et al. Motion of the hindfoot after simulated arthrodesis. J Bone Joint Surg Am. 1997; 79(2):241-246.
2.     O’Malley MJ, Deland JT, Lee KT. Selective hindfoot arthrodesis for the treatment of adult acquired flatfoot deformity: an in vitro study. Foot Ankle Int. 1995:16(7):411-417.
3.     Jeng CL, Vora AM, Myerson MS. The medial approach to triple arthrodesis: indications and technique for management of rigid valgus deformities in high risk patients. Foot Ankle Clin. 2005;10(3):515-21.
4.     Jeng CL, Tankson CJ, Myerson MS. The single medial approach to triple arthrodesis: a cadaver study. Foot Ankle Int. 2006;27(12):1122-5.
5.     Sammarco VJ, Magur EG, Sammarco GJ, et al. Arthrodesis of the subtalar and talonavicular joints for correction of symptomatic hindfoot malalignment. Foot Ankle Int. 2006;27(9):661-666.
6.     Lee MS. Medial approach to the severe valgus foot. Clin Podiatr Med Surg. 2007;24(4):735-744.
7.     Knupp M, Schuh R, Stufkens SA, et al. Subtalar and talonavicular arthrodesis throuhg a single medial approach for the correction of severe planovalgus deformity. J Bone Joint Surg Br. 2009;91(5):612-615.
8.     Brillhault J. Single medial approach to modified double arthrodesis in rigid flatfoot with lateral deficient skin. Foot Ankle Int. 2009;30(1):21-26.
9.     Weinraub GM, Schuberth JM, Lee M, et al. Isolated medial incisional approach to subtalar and talonavicular arthrodesis. J Foot Ankle Surg. 2010;49(4):326-330
10.     Philippot R, Wegrzyn J, Besse JL. Arthrodesis of the subtalar and talonavicular joints through a medial surgical approach: a series of 15 cases. Arch Orthop Trauma Surg. 2010;130(5):599-603.
11.     Anand P, Nunley JA, DeOrio JK. Single-incision medial approach for double arthrodesis of hindfoot in posterior tibialis tendon dysfunction. Foot Ankle Int. 2013;34(3):338-344.
12.     Hyer CF, Galli MM, Scott RT, et al. Ankle valgus after hindfoot arthrodesis: a radiographic and chart comparison of the medial double and triple arthrodesis. J Foot Ankle Surg. 2013; 53(1):55-58.
13.     Graves SC, Mann RA, Graves KO. Triple arthrodesis in older adults: results after long-term follow-up. J Bone Joint Surg. 1993; 75(3):355-362.

No.

Despite the emergence of the medial double arthrodesis, this author points out possible flaws with the procedure and notes a number of patient populations for whom the triple arthrodesis may be beneficial.

By Mark Hofbauer, DPM, FACFAS

The triple arthrodesis is near extinction or, at the very least, is on the endangered species list. For years, the triple arthrodesis was the go-to procedure for treating many of the complex rearfoot deformities that lead to significant pain and loss of function. Today, many believe that, in the sensate foot, there is no longer a place for the triple arthrodesis.

The relatively new procedure phenomenon that appears to be sweeping through the foot and ankle community is the medial double arthrodesis. With all new phenomena, we sometimes need to step back and reevaluate outcomes, focus on patient selection criteria and ultimately measure whether new techniques are providing better results than what historically has been a great option.

Specifically, Pell and colleagues studied triple arthrodesis with rigid screw fixation and realignment of the joint surfaces without resection of wedges in 132 feet in 111 patients with an average follow-up of five years.¹ Citing improvements in the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score and good patient satisfaction, the authors found the triple arthrodesis to be effective for addressing functional deficits, facilitating pain relief and improving functional deficits.

However, arguments abound in regard to the complications that can occur with the lateral incision skin dehiscence that surgeons sometimes see in the severely deformed foot after a triple arthrodesis. Advocates have suggested that one of the benefits of performing a medial double arthrodesis is the ease at which surgeons can perform the procedure with just one small incision and less risk of complication and morbidity.

Many have questioned the advantage gained with fusion of the calcaneocuboid joint. Other researchers have argued that placing lateral fixation at the calcaneocuboid joint assists in resisting the propensity for the foot to return to its preoperative deformity, especially the abducted position.² In a retrospective review, Burrus and coworkers assessed nine patients who had a modified double arthrodesis and seven who had a modified triple arthrodesis. The authors found that a modified double arthrodesis led to significantly more non-union and incomplete union with worse subjective outcome scores in comparison with triple arthrodesis.²

Which Patients Would Benefit From A Triple Arthrodesis?

Triple arthrodesis is the gold standard for the Charcot reconstruction patient. Stabilizing the entire rearfoot complex is a necessity in this patient population. One must achieve lateral column stability in these patients and this cannot happen with a medial double arthrodesis.

Surgeons can also employ the triple arthrodesis to address the cavus foot with associated rearfoot pain and pathology. Reducing the varus tilt/drift and shortening the lateral column is paramount in these patients. One can best achieve these goals with a triple arthrodesis.

In the severe flatfoot deformity with associated lateral column insufficiency, it can be very difficult to reduce the forefoot varus/supinatus with a medial double arthrodesis. When performing a medial double arthrodesis on patients with this foot type, concomitant medial column arthrodesis procedures, such as a Lapidus, are often necessary to obtain a proper forefoot to rearfoot relationship. A triple arthrodesis in this patient population makes it easier to “close down” or derotate the varus forefoot deformity, and realign the medial column.³

Many of these severe pes planovalgus patients suffer from global rearfoot pain along the lateral column of the calcaneocuboid joint. It is not uncommon in this patient type to see significant subchondral and degenerative changes at the calcaneocuboid joint on computed tomography (CT) scan. The triple arthrodesis is the procedure of choice for these patients.  

With end-stage flatfoot patients undergoing rearfoot arthrodesis reconstruction, proper positioning is often difficult. Considering the proper fusion sequence, after one has fixated the subtalar joint and reduced and fixated the medial column, surgeons often displace the cuboid plantarly and rotate it in the frontal plane.⁴ These patients require repositioning of the cuboid both in the dorsal and frontal plane, and surgeons can only achieve this by converting to a triple arthrodesis.

A Closer Look At Complications With The Medial Double Arthrodesis

Like all new procedures and techniques, the medial double arthodesis is not without complications.

Many of us are already beginning to see patients who develop a valgus ankle articulation due in part to loss of integrity of the anterior deltoid ligament as this structure is compromised with the dissection of the medial double arthrodesis. These patients ultimately require imbrication of the deltoid ligament and even a syndesmotic repair to correct this iatrogenic deformity.

A number of patients who have a medial double arthrodesis likewise develop a significant naviculocuneiform joint fault post-fusion. Admittedly, this can sometimes happen following a triple arthrodesis as well. However, I believe the extent of soft tissue dissection and joint distraction required with a medial double arthrodesis leads to excessive spring ligament destruction and an increased risk of naviculocuneiform joint fault.

Perhaps a medial-lateral double arthrodesis with one small medial incision over the talonavicular joint and one small sinus tarsi incision laterally may be the answer for some patients. Occasionally, a patient may require a posterior calcaneal displacement osteotomy along with a rearfoot fusion. These patients would benefit more from a medial double arthrodesis by avoiding the proximity of two lateral incisions.

In Conclusion

The triple arthrodesis, when done properly, can provide excellent reproducible results. The triple arthrodesis gives you a better ability to manipulate and restore normal anatomical alignment in the severely deformed foot in comparison to a medial double arthrodesis. Most patients undergoing a triple arthrodesis are able to return to normal function with less energy expenditure. The majority of these patients have high satisfaction scores and require no further surgical intervention.

Dr. Hofbauer is a Diplomate of the American Board of Foot and Ankle Surgery, and a Fellow of the American College of Foot and Ankle Surgeons. He is a member of The Orthopedic Group in Pittsburgh.

References
1.     Pell RF 4th, Myerson MS, Schon LC. Clinical outcome after primary triple arthrodesis. J Bone Joint Surg. 2000; 82(1):47–57.
2.     Burrus MT, Werner BC, Carr JB, Perumal V, Park JS. Increased failure rate of modified double arthrodesis compared with triple arthrodesis for rigid pes planovalgus. J Foot Ankle Surg. 2016; 55(6):1169-1174
3.     Maskil MP, Loveland JD, Mendicino RW, Saltrick K, Catanzariti AR. Triple arthrodesis for the adult-acquired flatfoot deformity. Clin Podiatr Med Surg. 2007; 24(4):765-778.
4.     Catanzariti AR, Mendicino RW, Whitaker JM, et al. Realignment considerations in the triple arthrodesis. J Am Podiatr Med Assoc. 2005;95(1):13–7.