Are IM Nails More Effective Than Plating For Charcot Hindfoot And Ankle Procedures?

Point

Yes. While plating has a role, this author says current evidence, bone healing principles and the potential for earlier weightbearing support retrograde intramedullary nailing in this patient population. 

By Noman Siddiqui, DPM, FACFAS

Retrograde intramedullary (IM) nailing is an effective surgical method for managing deformities of the hindfoot and ankle in Charcot neuroarthropathy.^1,2 This technique continues to gain popularity among podiatric surgeons due to advancements in fixation and comfort with medullary nailing in surgical training. Although surgeons commonly employ retrograde IM nailing for fracture management of long bones, one can readily apply the AO principles with this technique to fusion of the hindfoot and ankle in patients with a complex diabetic neuropathic fracture.³

The four commonly summarized AO principles are as follows:³

• restoration of anatomical relationships;
• fracture fixation providing absolute/relative stability;
• preservation of vascularity to bone and soft tissue (atraumatic technique); and
• early mobilization.

If non-surgical methods fail and one chooses surgical intervention to resolve these concerns, one of the goals is to create a stable foot that can support shoe gear and allow for community ambulation. Some of the more common challenges in a neuropathic joint of the hindfoot and ankle include: the potential loss of structural stability due to bone loss or defect; open wounds/deep infection; and an inability to ambulate with or without bracing. If we stick to our AO principles, it becomes obvious that IM nailing can address each of these concerns. 

Key Considerations With Restoration Of Anatomical Relationships

One of the bony consequences of a neuropathic ankle or subtalar joint is a potential for loss of alignment via the talus or subtalar joint. When there is involvement of the tibio-talar joint, the surgeon can approach this arthrodesis by attempting a tibiotalocalcaneal fusion with precision. Many of the commercially available IM nails are straight and will help restore anatomic realignment of the hindfoot and ankle by virtue of placement of the cannulated instrumentation from the calcaneus to the distal tibia. One can achieve this with minimal manipulation of the bony segments and realignment is rapid and accurate. 

One challenge that can arise is loss of the talus. Talar collapse or dissolution will have a significant impact resulting in a loss of height and anatomic bony fusion surface. This segmental defect may require an arthrodesis of the calcaneus to the distal tibia. Intramedullary nailing technology has improved with most systems offering internal and external compression of the IM nail. Though not a feature in the original nailing systems surgeons used for traumatic fractures, the combination of nailing principles with the compression we have seen with plates is of significant benefit in obtaining good bony contact for arthrodesis. Additionally, the alignment jigs associated with IM nailing provide additional support in restoring realignment.  

For me, IM nailing is especially helpful not only in restoring realignment but in maintaining length in this population when I combine limb lengthening techniques at the supramalleolar level. The IM nail facilitates early removal of external fixation devices that surgeons may use for limb lengthening in this population. It also serves as an excellent adjunct to provide stability to the fusion and length regeneration. 

Assessing The Benefits Of IM Nailing In Enhancing Stability With Fracture Fixation 

This leads me to my second argument. In fracture management, IM nails act as internal splints within the bone that are designed to share the load.⁴ This principle is helpful in IM nailing of the Charcot hindfoot and ankle since it provides numerous benefits. Intramedullary nails due to medullary bone contact are able to provide tremendous stability to bending and rotational forces. These forces along with others can increase the likelihood of nonunion. Therefore, minimizing rotation, shear and bending moments to the fusion site is an important step in obtaining a successful outcome.  

Plating options can be restricted in this arena due to the limitation in appropriate anatomic locations conducive to safe placement. Intramedullary nails can traverse a long distance up the tibial canal in a retrograde fashion, adding further stiffness to the fixation while plating is focal to the arthrodesis site. Furthermore, most plates utilize locked plating technology that limit motion at the arthrodesis site while IM nails can provide compression and early dynamization to the arthrodesis site. The ability to allow axial loads through a nail and ultimately through the fusion mass allows for secondary callus formation, which creates a robust arthrodesis. Locked plating will decrease the potential for micromotion, thus requiring primary bone healing, which can be a significant challenge in the diseased bone as one sees with neuropathic patients. 

Emphasizing An Atraumatic Technique With IM Nailing 

A major drawback to plating is the amount of periosteal stripping required to achieve contact between bone and plate. A common approach to plating is via an extensile lateral incision and removal of the fibula to later use as a buttress or onlay graft. This requires significant dissection and disruption of the distal peroneal and posterior tibial perforator arteries as described by Schaverien and Saint-Cyr.⁵ Along with the periosteal stripping that may occur, this vascular disruption can be a double strike not only against bone healing but soft tissue healing of the superficial structures. 

Intramedullary nailing diminishes the need for extensile approaches. One can find descriptions of arthroscopic and mini-open approaches in the literature.⁶ These pathways can facilitate a “percutaneous” placement of the IM nail. Although there is disruption of the endosteal blood supply during reaming of the canal, Rhinelander and colleagues have demonstrated an increase in the periosteal blood supply after medullary reaming.⁷ Additionally, animal models demonstrate that IM reaming will increase the blood supply to the surrounding soft tissue and muscle.^8,9

Crucial Principles With Early Mobilization In A High-Risk Population

One cannot emphasize this principle enough. The patient with diabetes, neuropathy and Charcot often deals with multiple comorbidities that make healing a significant challenge. One of the major post-surgical intervention challenges is offloading. This is very difficult in the neuropathic population and is not without increased risk for deep vein thrombosis (DVT) and other factors. 

With plating, it becomes imperative to provide an appropriate amount of time non-weightbearing to allow for radiographic signs of healing to prevent fatigue of the fixation and bony segments. This prolonged immobilization is a challenge in this cohort. With IM nailing and placement of the appropriate length nail, the properties of the nail allow for early and immediate load transfer. Nails that are longer (greater than 300 mm) and fit within the isthmus of the tibial canal can provide enough stability for early weightbearing. Nails that are shorter (150 to 200 mm) may not provide the same benefits of IM nailing and may pose a risk for tibial fracture. 

The authors of various studies and systematic reviews have looked at the effectiveness of IM nailing. Jehan and colleagues presented a systematic review on 613 tibiotalocalcaneal arthrodeses with IM nails and reported a union rate of 87 percent.¹ In that review, 342 patients with diabetes and Charcot neuroarthropathy had a union rate of 79 percent but the study authors noted a 40 percent complication rate.¹ In 2015, Wukich and team looked at retrograde IM nailing in those with and without diabetes.² For patients with diabetes, they reported a limb salvage rate of approximately 97 percent, which was similar to those without diabetes.² Both studies show the effectiveness of the technique in this very challenging patient population. 

In Summary

There are numerous factors that determine outcomes in this patient population. The method of fixation is one element when trying to achieve a good result. Utilizing IM fixation meets the most basic fundamental principles of healing in a population that has a high potential for complications. However, despite the risk of complications, I feel that one can safely utilize IM nails to correct Charcot neuroarthropathy of the foot and ankle. 

Dr. Siddiqui is the Director of Podiatric Surgery and the Deformity Correction and Orthoplastics Fellowship at the Rubin Institute for Advanced Orthopedics/International Center for Limb Lengthening in Baltimore. 

Counterpoint

No. In a complex patient population, the choice of fixation is crucial. Noting conflicting literature and sharing practical pearls from their experience, these authors maintain that intramedullary nailing is not without its disadvantages.

By H. John Visser, DPM, FACFAS, Blake T. Savage, DPM and Raul Aviles, DPM

Management of the Charcot ankle and hindfoot can be an extreme challenge as one is treating a limb- and possibly life-threatening condition. Often, the patient has peripheral vascular disease and profound neuropathy as well as multiple medical comorbidities. Ensuring adequate medical optimization for these conditions is paramount to any considered operative intervention. 

Achieving proper stable fixation in the neuropathic limb that is tolerant of the soft tissues is an arduous task. The Charcot neuropathic ankle and hindfoot may present in a varus, valgus or multiplanar position. This may be secondary to ligamentous instability, arthrosis or avascular necrotic changes of the talus. In more severe cases, there is significant osteopenia secondary to disuse or the Charcot metabolic process itself. This active inflammatory process and imbalance between the receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin systems greatly weakens the osseous skeleton. This makes fixation very difficult. Correspondingly, the compromised soft tissue envelope also poses a potential hazard.

These conditions then affect the vulnerable and highly cancellous talus. Extreme destruction of the talar body can occur with resultant severe instability and deformity. Fragmentation due to loss of vascular perfusion and difficulty discerning the remaining talar viability further complicate the operative process. At times, the talus itself is completely lost. Complications may include delayed union, non-union, inadequate fixation, loss of fixation, implant failure and infection.^1,2 

What The Research Reveals About Fixation Options

It then becomes useful to identify a fixation technique for a tibiotalocalcaneal (TTC) or tibiocalcaneal (TC) arthrodesis that provides optimal stability in the presence of the compromised osseous skeleton (poor bone stock).¹ Both forms of arthrodesis form the bullwork of Charcot ankle and hindfoot conditions. Standard forms of fixation include intramedullary nails, humeral blade plates, periarticular locking plates and external fixators. 

Published biomechanical studies comparing IM nailing to fixed angle anatomic plating conflict in their conclusions regarding superiority.^2-10 One comparison of IM nailing versus fixed angle plating dealt with the placement of IM nails through a posterior Achilles tendon splitting approach and inserting the plates through a lateral transfibular approach.³ While the authors found both techniques to be adequate, they conceded that the study was too underpowered to determine if a significant difference existed. Radiographic union occurred in 71 percent of the IM nail cases and in 64 percent of the plated cases. The researchers noted symptomatic non-union requiring reoperation in 16 percent of IM nail cases and seven percent of plate cases. Of these reoperation procedures, 82 percent of the patients went on to fusion.3 With the more robust posterior Achilles tendon splitting approach, four out of 38 patients had a superficial wound breakdown and cellulitis and the group who had the lateral transfibular approach fell within a range of wound complications of five to 13.3 percent.³

Comparing retrograde IM nails versus humeral blade plates in tibiotalocalcaneal arthrodesis, the study authors found the overall performance of the two constructs with respect to initial stability was similar. There were no significant differences between torsion or cantilever bending load configuration.³

Another cadaveric model study compared locking plate constructs to the retrograde IM nail and found the final rigidity of the IM nail was inferior to that of the locking plate.8 However, surgeons have not been able to reproduce these findings. Intramedullary nails, blade plates and locking plates also show similar biomechanical properties.^3,8-10 

In comparison to screw and nail fixation, plating usually requires a more extensile (usually transfibular) approach to the ankle and hindfoot with more extensive soft tissue dissection. This can lead to delayed healing in the ankle region with more potential for angiosome compromise.¹¹ But as stated, literature reports show similar wound healing results. Anatomic periarticular locking plates provide rigid, fixed angle fixation and researchers have described these plates as internal fixation.^8,12 These plates offer advantages to standard plating in osteopenic bone with the utilization of incorporated locking screws.¹ 

Blade plates are also a possible form of fixation in the neuropathic ankle and hindfoot. Multiple studies have found that a straight humeral locking plate construct with single plane holes is no different from an IM nail construct when it comes to initial stiffness, torsional loading failure and construct deformation in a tibiotalocalcaneal cadaver model.^1,13 Securing the blade into the soft osteopenic bone serves to lock the proximal plate to the tibia. The four cortices of contact in the proximal standard form of the plate offer rigid stabilization. Blade plate placement is, however, technically challenging because of the fixed position of the blade in three dimensions. This makes it hard to contour to the anatomic shape of the lateral tibia, talus and calcaneus. 

Anatomic periarticular locking plates, due to the contours and screw holes that allow periaxial alignment, prove much easier to insert than a blade plate.¹ This is especially true when there is a large talar defect that requires extensive bone grafting. 

Complications Of IM Nailing: What You Should Know

Perceived advantages to retrograde IM nailing are easier placement and less extensive surgical dissection.1 Posterior Achilles splitting and anterior incisions are possible, but there are also distinct disadvantages. Relative contraindications include poor bone quality, posttraumatic tibial deformity as a result of previous trauma and, most importantly, the presence of prior infection involving the soft tissue envelope and bony architecture. This can include prior osteomyelitis in the vicinity of the resection site and those secondary to pin tracts during utilization of an external fixator.¹ 

Two other main issues include soft tissue or neurovascular injury at the nail insertion site, and cortical stress reactions or fractures involving the tibia at the proximal aspect of the nail.³ Despite the presence of neuropathy, postoperative nerve entrapment symptoms can be troublesome and can potentially generate complex regional pain syndrome (CRPS) II. Vascular injury to the lateral plantar artery may also lead to distal ischemia, which can lead to soft tissue and appendage compromise, and ensuing necrosis.^3,14\

In regard to tibial stress fracture conditions with IM nail utilization, one study compared a standard length (15 cm) ankle arthrodesis nail and an identical longer device terminating at the proximal tibial metaphysis.¹⁵ After insertion with the appropriate technique, investigators placed strain on the posterior cortex of the tibial specimen. The standard nail length showed 5.3 times the stress in comparison to the locked long nail at the posterior cortex where the nail ended. The study authors surmised that with weightbearing, there is risk of failure at the proximal screw holes. This may have subsequently lead to postoperative fractures of the tibia that surgeons have observed clinically.¹⁵

Pertinent Considerations With Plating

Surgeons may utilize anatomic periarticular plating through anterior, posterior Achilles splitting and lateral transfibular approaches. There are numerous plating systems for the anterior, posterior and lateral ankle. However, providers much first address any source of ulceration or infection. Characteristically, static external fixation frames allow offloading and healing of existing ulceration. Periarticular plating is especially preferable when much of the talus remains preserved. One may perform deformity correction after soft tissue dissection and preparation of the bony surfaces by curettage or manual cuts. With an anterior approach, the plate addresses the ankle joint only and the subtalar joint warrants attention separately through a modified Ollier approach.

If the surgeon cannot accomplish correction of ankle and hindfoot deformity of varus or valgus with curettage or manual cuts, an indirect calcaneal osteotomy may allow further deformity correction. With the posterior Achilles splitting approach, one can address both the ankle and subtalar joints with a single incision, and fixate with an anatomically-designed plate. 

In cases of more significant deformity with significant or total loss of the talus, a transfibular approach is preferable. The surgeon makes an incision 10 cm above the ankle and osteotomizes the fibula six to eight cm above the ankle joint. One would subsequently morselize the fibula in a bone mill or use it at the end of the case as a lateral strut to help augment the fusion. In the Charcot ankle and hindfoot, surgeons must take care to remove non-viable bone. This is especially the case when avascular necrotic bone is present within the remaining talar body. 

Depending on the defect size, degree of deformity, risk of nonunion and quality of bone at the prepared surfaces, one may consider multiple approaches. These options may include: cancellous allograft chips impregnated with platelet-rich plasma (PRP) or bone marrow aspirate; morselized autograft from the resected fibula; or complete or contoured femoral head reinforced with orthobiologic products including recombinant bone morphogenetic protein-2 or -7. Internal bone stimulation is also an option with large bulk allografts.³ However, despite an advanced technique with bulk allografts, the literature reveals a 50 percent failure rate. Failure correlates to the size of the graft. Creep at the edges of the graft along with dissolution of the center of the graft result in collapse.¹⁴

When a significant portion of the talus remains, grafting the defects with tightly packed allograft or autograft is an option. Lateral anatomic plates will contour to this form of the ankle anatomy. An IM nail, in the senior author’s mind, will disturb this tightly filled graft interface. In cases of complete talar loss, large 8.0 mm, fully-threaded cancellous screws can act as a “strut” to maintain the original height of the lost talus. One can then tightly fill the defect with the supplementation of cancellous bone chips as an allograft with bone marrow aspirate or orthobiologics we have previously described. A large femoral locking plate contours well to the lateral tibia. Calcaneal anatomy then protects the graft and reinforces the established length. 

One can also employ tibiocalcaneal arthrodesis in cases of significant deformity and talar loss. Stability is key and built-in shoe lifts of the midsole can help manage leg length. Specific anatomic plating is available for this form of arthrodesis.

Utilization of retrograded IM nails in cases of bone loss and larger bulk allografts proves quite difficult. Stabilization of the foot to the leg in the frontal and sagittal planes is problematic. Often, in these cases of intercalary grafting, the nail is not compressed and serves only as splintage. Also, encroaching “coring out” of the graft leads to compromise of the creeping substitution process of graft incorporation. 

In Conclusion

Management of the Charcot ankle and hindfoot can be a distinct surgical challenge. Highly complicating factors can occur with surgical intervention. The utilization of plating enables surgeons to accurately correct deformity and allows graft incorporation and stability. One best achieves maintenance of blood supply to the fusion surfaces or augmented grafted surface with this source of osteosynthesis in the Charcot ankle and hindfoot.

Dr. Visser is the Director of the Podiatric Residency Program at SSM Health DePaul Medical Center in St. Louis. He is a Fellow of the American College of Foot and Ankle Surgeons, and a Diplomate of the American Board of Foot and Ankle Surgery. 

Dr. Savage is a second-year resident at SSM Health DePaul Medical Center in St. Louis. 

Dr. Aviles is a second-year resident at SSM Health DePaul Medical Center in St. Louis. 

Point References

1. Jehan S, Shakeel M, Bing AJ, Hill SO. The success of tibiotalocalcaneal arthrodesis with intramedullary nailing—a systematic review of the literature. Acta Orthop Belg. 2011;77(5):644–651.
2. Wukich DK, Mallory BR, Suder NC, Rosario BL. Tibiotalocalcaneal arthrodesis using retrograde intramedullary nail fixation: comparison of patients with and without diabetes mellitus. J Foot Ankle Surg. 2015;54(5):876-882. 
3. AO Trauma. Education. Available at: https://aotrauma.aofoundation.org/education . Accessed August 12, 2020.
4. Bong MR, Kummer FJ, Koval KJ, Egol KA. Intramedullary nailing of the lower extremity: biomechanics and biology. J Am Acad Orthop Surg. 2007;15(2):97-106. 
5. Schaverien M, Saint-Cyr M. Perforators of the lower leg: analysis of perforator locations and clinical application for pedicled perforator flaps. Plast Reconstr Surg. 2008;122(1):161-170. 
6. Raikin SM. Arthrodesis of the ankle: arthroscopic, mini-open, and open techniques. Foot Ankle Clin. 2003;8(2):347-359.
7. Rhinelander FW, Peltier LF. Effects of medullary nailing on the normal blood supply of diaphyseal cortex. Clin Orthop Rel Res. 1998;350:5-17.
8. Hupel TM, Aksenov SA, Schemitsch EH. Muscle perfusion after intramedullary nailing of the canine tibia. J Trauma. 1998;45:256-262.
9. Schemitsch EH, Kowalski MJ, Swiontkowski MF. Soft-tissue blood flow following reamed versus un- reamed locked intramedullary nailing: A fractured sheep tibia model. Ann Plast Surg. 1996;36(1):70-75.

Counterpoint References

1. Ohlson BL, Shatby MW, Parks BG, White KL, Schon LC. Periarticular locking plate vs intramedullary nail for tibiotalocalcaneal arthrodesis: a biomechanical investigation. Am J Orthop. 2011;40(2):78-83.

2. Chiodo CP, Acevedo JI, Sammarco VJ, et al. Intramedullary rod fixation compared with blade-plate-and-screw fixation for tibiotalocalcaneal arthrodesis: a biomechanical investigation. J Bone Joint Surg. 2003;85(12):2425-2428.

3.  Mulligan RP, Adams SB, Easley ME, DeOrio JK, Nunley JA. Comparison of posterior approach with intramedullary nailing versus lateral transfibular approach with fixed-angle plating for tibiotalocalcaneal arthrodesis. Foot Ankle Int. 2017;38(12):1343-1351. 

4. Chodos MD, Parks BG, Schon LC, Guyton GP, Campbell JT. Blade plate compared with locking plate for tibiotalocalcaneal arthrodesis: a cadaver study. Foot Ankle Int. 2008;29(2):219-224. 

5. Mann MR, Parks BG, Pak SS, Miller SD. Tibiotalocalcaneal arthrodesis: a biomechanical analysis of the rotational stability of the Biomet Ankle Arthrodesis Nail. Foot Ankle Int. 2001;22(9):731-733. 

6. Means KR, Parks BG, Nguyen A, Schon LC. Intramedullary nail fixation with posterior-to-anterior compared to transverse distal screw placement for tibiotalocalcaneal arthrodesis: a biomechanical investigation. Foot Ankle Int. 2006;27(12): 1137-1142. 

7. O’Neill PJ, Parks BG, Walsh R, Simmons LM, Schon LC. Biomechanical analysis of screw-augmented intramedullary fixation for tibiotalocalcaneal arthrodesis. Foot Ankle Int. 2007;28(7):804-809.

8. O’Neill PJ, Logel KJ, Parks BG, Schon LC. Rigidity comparison of locking plate and intramedullary fixation for tibiotalocalcaneal arthrodesis. Foot Ankle Int. 2008;29(6):581-586. 

9. Alfahd U, Roth SE, Stephen D, Whyne CM. Biomechanical comparison of intramedullary nail and blade plate fixation for tibiotalocalcaneal arthrodesis. J Orthop Trauma. 2005;19(10):703-708. 

10. Froelich J, Idusuyi OB, Clark D, et al. Torsional stiffness of an intramedullary nail versus blade plate fixation for tibiotalocalcaneal arthrodesis: a biomechanical study. J Surg Orthop Adv. 2010;19(2):109-113. 

11. Mueckley TM, Eichorn S, Von Oldenburg G, et al. Biomechanical evaluation of primary stiffness of tibiotalar arthrodesis with an intramedullary compression nail and four other fixation devices. Foot Ankle Int. 2006;27(10):814-820.

12. Egol KA, Kubiak EN, Fulkerson E, Kummer FJ, Koval KJ. Biomechanics of locked plates and screws. J Orthop Trauma. 2004;18(8):488-493. 

13. Bussewitz B, DeVries JG, Dujela M, et al. Retrograde intramedullary nail with femoral head allograft for large deficit tibiotalocalcaneal arthrodesis. Foot Ankle Int. 2014;35(7):706-711. 

14. Hutchinson B, Schweitzer MJ. Revision Surgery for Failed Total Ankle Replacement. Clin Podiatr Med Surg. 2020;37(3):489-504. 

15. Noonan T, Pinzur M, Paxinos O, Havey R, Patwardhin A. Tibiotalocalcaneal arthrodesis with a retrograde intramedullary nail: A biomechanical analysis of the effect of nail length. Foot Ankle Int. 2005;26(4):304-308.

16. Thomas RL, Sathe V, Habib SI. The use of intramedullary nails in tibiotalocalcaneal arthrodesis. J Am Acad Orthop Surg. 2012;20(1):1-7.