When Hammertoe Surgery Fails
Hammertoe surgery failures can lead to complications such as nonunion, infection and vascular compromise. Accordingly, these authors emphasize the importance of thorough patient assessment, review the literature findings on fixation choices and discuss how to address common complications.
Hammertoes are the most common lesser toe deformities, making up 48 percent of all forefoot surgeries.1–3 Research shows that 60 million patients suffer from hammertoe deformities. Approximately 30 percent of hammertoe patients present with single toe involvement while an estimated 40 percent of individuals have greater than three digits involved.1,4–10 In 2012, an estimated 550,000 patients had surgical intervention for the correction of hammertoe deformities.9
The hammertoe deformity is complex and multifactorial. The pathologic entity is not always solely foot-related but also involves underlying systemic origins such as inflammatory arthritis, diabetes mellitus, neuromuscular disorders, lumbosacral disc complexities and postural deformities.4 The notion that “one procedure fits all” does not apply to hammertoe deformity and when the patient goes to the operating room without a comprehensive preoperative evaluation and strategic intraoperative plan, failures are bound to occur.
Despite the variety of approaches to reduce a digital deformity, there is no established gold standard. Common procedures include excisional arthroplasty, arthrodesis of the interphalangeal joints, tendon releases, tendon transfers, metatarsal osteotomies and plantar plate repairs. The most common complications that can arise for surgical failures include: nonunion, malunion, dactylitis, infection, neuritis, painful scarring and recurrence of deformity.
What The Literature Reveals About Fixation Techniques For Hammertoe Correction
In today’s market, there is an extensive array of fixational techniques, which can make selecting the optimal hardware overwhelming. Surgeons should be comfortable with using several modalities when treating hammertoes. The most commonly used devices are percutaneous and buried Kirschner wires (K-wires), absorbable pins, cannulated intramedullary screws, and intramedullary implants.4,5,7,10 K-wires are still the most commonly used devices today but they are not free of complications.4
Reece and colleagues reported an 18 percent incidence of pin tract infections occurring when percutaneous wires were left for more than six weeks.7 Caterini and colleagues report a nearly 20 percent rate of nonunion after proximal interphalangeal arthrodesis.11,12
Absorbable pins operate similar to K-wires and one may use them percutaneously or buried. Konkel and coworkers reported an 87 percent fusion rate with absorbable pins for hammertoe.13 However, absorbable pins have caused foreign body reactions and a loss of mechanical function.4,14,15
Cannulated screws reportedly have a high fusion rate of 94 percent but disadvantages include risk of breakage, painful hardware, infection, a second operation for hardware removal and disruption of the distal interphalangeal joint.4,12,16
Basile and colleagues used a permanent one-piece intramedullary device and reported an incidence of fusion and adequate radiographic alignment of 84 percent in hammertoe patients.4 Catena and coworkers utilized a one-piece intramedullary implant with concomitant use of K-wires for three to four weeks, and reported a 78 percent union rate in hammertoe patients.5
It would be easy to blame the choice of implant for our failures but it is important to recognize that not all failures of hammertoe repair are related to the type of device we use.17 Defining a surgery as a failure is not straightforward as there are multiple considerations to take into account. Not all patients are seeking surgical intervention solely for pain relief. A successful surgery for one patient could be deemed a failure for another. For the sake of this article, we define hammertoe surgical failures as a reflection of inappropriate use of fixation, improper technique and inadequate preoperative evaluation.17 An operative plan needs to take into account multiple variables that include not only the severity of the deformity but also age, lifestyle, patient expectations and the etiology of the deformity.1,10
Salient Principles For Patient Evaluation And Assessment
When dealing with unsuccessful hammertoe surgery, it is imperative for the surgeon to discern patients who are dissatisfied versus those who would actually benefit from a revisional procedure. Careful patient selection is the first step in preventing unwanted challenges. One important determination includes if the patient is seeking surgery for pain relief or if he or she has purely cosmetic-related complaints. Patients need to understand the inherent risks and potential complications of a revisional procedure.
As the surgeon, one must fully explain the treatment plan in order for patients to have realistic expectations of their potential outcomes.18 For example, patients may believe surgery could resolve stiffness in the digit. However, it is the responsibility of the surgeon to verify that while the stiffness will not resolve with a proximal interphalangeal joint arthrodesis, the arthrodesis will correct the deformity. By implementing this approach with patient communication in your practice, postoperative dissatisfaction will decrease.
The surgeon should primarily determine what aspects of the deformity the surgery failed to address and how to rectify each factor. Ascertaining a thorough history and physical with an in-depth report of the patient’s previous surgery is critical along with localization of pain, assessment of the anatomical etiology of the pain, and determining the severity of the persistent deformity.18 It is also important to obtain recent weightbearing radiographs for possible surgical planning. If the patient has a possible underlying inflammatory condition, neurologic or vascular disorder, one should perform the proper workup.18
When performing the physical exam, identify the rudimentary biomechanical forces. Digital anatomy is detailed and one should have a full understanding of the biomechanical forces acting on the lesser digits prior to intervention. Without knowing the complexities of the soft tissue and how they act, malreduction of the deformity will occur.18
When dealing with surgical failures, surgical revision should be a last case scenario. One should exhaust conservative options prior to revisional surgery. Along with padding, medications and physical therapy, shoe gear and orthotic modifications are excellent options to accommodate painful hammertoes.18 If the patient is still experiencing pain, it is imperative for surgeons to inform the patient on the realistic chance of the patient’s pain improving with revisional surgery.
Rectifying Soft Tissue Compromise And Infection
Postoperative surgical site infection is the most common complication of forefoot surgery due to the digits’ anatomical position, propensity for edema and bacterial colonization.19 Despite the incidence of infection, one can resolve many postoperative wound infections with an oral antibiotic and close clinical follow-up.
A study from 2015 that looked at the use of K-wire fixation in hammertoe surgery demonstrated that 11 percent of patients received an oral antibiotic at an average 20-month follow-up while only 0.3 percent had a pin tract infection.20 Deep infections that may demonstrate the need for surgical debridement include abscess or osteomyelitis. The development of osteomyelitis may require six weeks of intravenous antibiotics if the patient has adequate perfusion and the infection is relatively stable. Otherwise, the surgeon should consider surgical debridement and amputation.20
How To Handle Neurologic Issues With Hammertoe Surgery
Neuritis or neuromas may occur as a result of lesser digit surgery. To prevent these complications, consideration for incision planning and soft tissue handling is critical. However, when complications arise and conservative measures fail, one may consider a neuroma surgery with neuromyodesis or the burial of the neuroma into the muscle belly.18
When Vascular Compromise Occurs
Vascular compromise such as ischemia needs to be a special consideration in patients at higher risk, including the elderly, those with peripheral vascular impairment such as Raynaud’s disease, and tobacco users.18 Similar to neurological complications, postoperative vascular compromise is largely associated with surgical technique including incisional approach, soft tissue handling and anatomic dissection.4 When it comes to postoperative delay in capillary refill, one may address this with one of the following methods: warm saline, placing the patient into a dependent position or loosening of the dressing.
In addition, there is anecdotal evidence for the topical use of nitroglycerine paste for reperfusion. If the diminished capillary refill persists for greater than one hour, loosening or removal of fixation is a suggestion.18 If dry gangrene persists, the surgeon may need to amputate the digit following demarcation.19 Persistent venous congestion may also occur. In this circumstance, the digit should remain in a horizontal position and one should not actively warm the digit to prevent further venous congestion.18
Key Insights On Hammertoe Malalignment And Recurrence
A number of malalignment deformities can occur secondary to digital surgery. The most common are metatarsophalangeal joint extension and recurrent hyperflexion of the deformity at the proximal interphalangeal joint.18 Metatarsophalangeal joint contracture most likely will require full capsular release and possible extensor tendon lengthening.21
One can correct continued flexion of the proximal interphalangeal joint with revision fusion or a flexor tendon tenotomy.18 Often after proximal interphalangeal joint fusion, the patient may present with distal interphalangeal joint flexion contracture and must have evaluation for a flexible or rigid deformity. A flexor tenotomy may correct flexible deformities or one can perform a distal interphalangeal joint arthroplasty. Take care to avoid shortening the toe too much to prevent flail toe. If a flail toe becomes intolerable, consider a bone graft and transfixion wire to regain stability.22
Another option is to shorten the remaining digits via arthroplasty or diaphysis shortening of the middle phalanx. Frontal plane malalignment can also occur and often is a result of poor surgical technique in the primary surgery. However, the surgeon can correct this frontal plane deformity with soft tissue release and an osteotomy such as a closing base wedge osteotomy.18
In addition to the importance of preoperative planning to reduce recurrence or malalignment, do not use fixation such as a K-wire intraoperatively to resist an uncorrected deforming force. This places the K-wire at high risk for failure and the deformity will predictably recur upon removal, therefore requiring revision.19
How To Treat A Nonunion
The nonunion rate of a proximal interphalangeal joint fusion is as high as 50 percent.18 Despite the rate of nonunion at the proximal interphalangeal joint, fibrous healing at that level often will yield clinical satisfaction.5
The distinction between a symptomatic and asymptomatic nonunion is critical in determining further treatment options. Treatment of a symptomatic nonunion can include orthotics or hardware removal with a revision procedure including altered fixation, increased orthobiologics or an excisional arthroplasty. To prevent nonunion, operative technique is critical including following principles of joint preparation and preoperative optimization.
When Fixation And Hardware Cause Complications
Fixation options for hammertoes include a variety of implants and Kirschner wire fixation with complications including dislodged implants or K-wire breakage. Dislodged implants require a revision surgery with removal of the implant and altering fixation, which can include a new larger implant if appropriate. One can supplement this with multiple K-wire fixation. Similarly, one may perform a revision surgery to remove a broken K-wire if the retained hardware is symptomatic. Surgeons can prevent K-wire breakage by using a 0.062-inch K-wire rather than smaller options.23
In Conclusion
Hammertoes have a multifactorial pathology that requires a comprehensive evaluation and physical, appropriate patient selection for surgical procedures, a thorough discussion of expectations and a well developed preoperative plan taking into account both soft tissue and osseous deforming forces. As we have discussed, hammertoe surgery failure is most often associated with preoperative procedure selection, demonstrating the importance of understanding the etiology and preoperative decision making.
In addition, one must implement diligent operative technique to prevent many of the most common postoperative complications. However, if hammertoe surgery failures occur, the revisional options we have discussed can provide beneficial treatment options.
Dr. Clifford is affiliated with CHI Franciscan Orthopedic Associates at St. Francis in Federal Way, Washington. He is the Residency Director at the Franciscan Foot and Ankle Institute in Federal Way, Washington. He is also a member of the Board of Directors of the International Foot and Ankle Foundation for Education and Research. Dr. Clifford is the Editor for the Foot and Ankle Online Journal.
Dr. Oexeman is a second-year resident at the Franciscan Foot and Ankle Institute in Federal Way, Washington.
Dr. Millonig is a second-year resident at the Franciscan Foot and Ankle Institute in Federal Way, Washington.
References
1. Mueller CM, Boden SA, Labib S, et al. Complication rates and short-term outcomes similar after hammertoe correction in older patients. Foot Ankle Orthop. 2017; epub Sept. 17.
2. Kwon JY, De Asla RJ. The use of flexor to extensor transfers for the correction of the flexible hammer toe deformity. Foot Ankle Clin. 2011;16(4):573–582.
3. Shirzad K, Kiesau CD, DeOrio JK, Parekh SG. Lesser toe deformities. J Am Acad Orthop Surg. 2011;19(8):505–514.
4. Basile A, Albo F, Via AG. Intramedullary fixation system for the treatment of hammertoe deformity. J Foot Ankle Surg. 2015; 54(5):910–916.
5. Catena F, Doty JF, Jastifer J, Coughlin MJ, Stevens F. Prospective study of hammer toe correction with an intramedullary implant. Foot Ankle Int. 2014; 35(4):319–325.
6. Lehman DE, Smith RW. Treatment of symptomatic hammertoe with a proximal interphalangeal joint arthrodesis. Foot Ankle Int. 1995; 16(9):535–541.
7. Reece A, Stone M, Young A. Toe fusing using Kirschner wire. J R Coli Surg Edimb. 1987; 32(2):158–159.
8. Schlefman BS, Fenton CF, McGlamry ED. Peg in hole arthrodesis. J Am Podiatry Assoc. 1983; 73(4):187–195.
9. Cook J, Johnson LJ, Cook EA. Anatomic reconstruction versus traditional rebalancing in lesser metatarsophalangeal joint reconstruction. J Foot Ankle Surg. 2018; 57(3):509–513.
10. Kernbach KJ. Hammertoe surgery: arthroplasty, arthrodesis or plantar plate repair? Clin Podiatr Med Surg. 2012;29(3):355–366.
11. Hyer CF, Scott RT. Current and emerging insights on hammertoe correction. Podiatry Today. 2012; 25(2):32–40.
12. Caterini R, Farsetti P, Tarantino U, Potenza V, Ippolito E. Arthrodesis of the toe joints with an intramedullary cannulated screw for correction of hammertoe deformity. Foot Ankle Int. 2004; 25(4):256–261.
13. Konkel KF, Sover ER, Manger AG, Halberg JM. Hammertoe correction using anabsorbable pin. Foot Ankle Int. 2011; 32(10):973–978.
14. Kontakis GM, Pagkalos JE. Bioabsorbable materials in orthopaedics. Acta Orthop Belg. 2007; 73(2):159–169.
15. Boestman OM. Osteoarthritis of the ankle after foreign body reaction to absorbable pins and screws. J Bone Joint Surg Br. 1998; 80(2):333–338.
16. Lane GD. Lesser digital fusion with a cannulated screw. J Foot Ankle Surg. 2005; 44(3):249–250.
17. Clifford C. Hammertoe fixation and cost-effectiveness: what are the best options? Podiatry Today. 2016; 29(1):40–46.
18. Solan MC, Davies MS. Revision surgery of the lesser toes. Foot Ankle Clin. 2011; 16(4):621–645.
19. Phisitkul P. Managing complications of lesser toe and metatarsophalangeal joint surgery. Foot Ankle Clin. 2018; 23(1):145-156.
20. Kramer WC, Parman M, Marks RM. Hammertoe correction with k-wire fixation. Foot Ankle Int. 2015;36(5):494–502.
21. Zingas C, Katcherian DA, Wu KK. Kirschner wire breakage after surgery of the lesser toes. Foot Ankle Int. 1995;16(8):504–9.
22. Myerson MS, Filippi J. Interphalangeal joint lengthening arthrodesis for the treatment of the flail toe. Foot Ankle Int. 2010;31(10):851–6.
23. Dhukaram V, Hossain S, Sampath J, et al. Correction of hammer toe with an extended release of the metatarsophalangeal joint. J Bone Joint Surg Br. 2002;84(7):986–90.