Citing preservation of motion and patient satisfaction among other benefits, these authors maintain that arthroplasty is a superior option to arthrodesis for hammertoe correction.
By Rachelle Randall, DPM and Lawrence Fallat, DPM, FACFAS
Hammertoes are one of the most common forefoot deformities and predominantly affect the second and third digits.1 These deformities lead to pain with ambulation and difficulty wearing everyday shoe gear. In our experience, the majority of patients seeking surgical correction for hammertoes are women. These patients look for cosmetic improvement, elimination of pain and the ability to get back into normal shoe gear. Coughlin found that a majority of patients with lesser toe abnormalities complain of pain and callous formation dorsal to the proximal interphalangeal joint (PIPJ) of the affected digit.2 This deformity leads to a poor cosmetic appearance and footwear irritation.
Understanding the etiology of the deformity is essential to determine appropriate treatment and achieve positive long-term results. Possible etiologies of hammertoes includes intrinsic muscle imbalance, neuromuscular conditions, an overcrowded toe box, hallux valgus deformity, long metatarsals, posttraumatic sequelae, congenital deformity and inflammatory arthropathies.3
Initially, these deformities start off as flexible and reducible. However, they can progress into contractures that require proper assessment and evaluation prior to surgical planning. This includes a discussion of patient expectations. The lesser toes are important for pressure distribution and balance of the foot. Any changes in musculature and biomechanical deformity may result in contracture of the digits and eventually evaluation for surgical correction.3
When discussing the major complaints and concerns contributing to a desire for surgery, cosmesis, function and reduction of pain are of the utmost importance. Our patients want to retain motion of the joint and achieve as “normal” appearing of a digit as possible after surgery while still reducing pain. In our experience, almost every patient, when given the option of fusion versus arthroplasty of the toe, will choose arthroplasty. When dealing with younger, active or athletic patients, we agree with Ellington that arthroplasty is significantly beneficial over arthrodesis.3 This is especially true in the older patient looking to retain function and motion of the toe.
What The Literature Reveals About Hammertoe Correction Outcomes
There is little research discussing long-term outcomes of arthroplasty for correction of hammertoe deformity. O’Kane and Kilmartin conducted the largest study to date looking at long-term outcomes for PIPJ arthroplasty in 75 patients (100 toes) with an average follow-up time of 44 months.4 Surgeons utilized longitudinal elliptical incisions for all patients and did not employ K-wire fixation for the arthroplasties.
The vast majority (94 percent) of patients in this study had a primary complaint of dorsal toe pain and irritation with shoe gear, which corresponds with our patient population.4 Postoperatively, none of the 75 patients reported dorsal pain or footwear irritation. Preoperatively, the American Orthopaedic Foot and Ankle Society (AOFAS) score average was 46. The average postoperative AOFAS was 94, which was statistically significant.4 The researchers also noted that the mean patient satisfaction on a visual analog scale (VAS) was 9.3/10 postoperatively. The most reported complication was flail toe in seven patients but this did not cause pain or prevent those patients from wearing shoe gear.4
The study by O’Kane and Kilmartin as well as other studies have found that PIPJ arthroplasty is also more acceptable than arthrodesis to patients due to the rapid return to activity in two weeks in comparison to three to six weeks with fusion.4-6
Complications after hammertoe correction of any kind may include recurrence, poor cosmetic changes due to swelling and skin changes. Although some studies suggest arthrodesis as a preferred primary surgical option, they do note complications with cosmesis and patient dissatisfaction due to the rigid toe structure.4 Coughlin and colleagues reported no long-term swelling after PIPJ arthrodesis in one study.7 However, in another study of PIPJ arthrodesis in 25 patients (62 toes), Ohm and team found that patients had a need for residual analgesics and experienced swelling and restriction of motion at the MPJ, leading to patient disappointment post-operatively.8
With the leading advantages of arthroplasty being continued motion and function of the toe without pain or deformity, it is important to also discuss the negative affects that arthrodesis of the PIPJ can have on the function of the digit. Multiple authors have noted that distal interphalangeal joint (DIPJ) instability, deformity and pain may result after arthrodesis of the PIPJ.4-6 Baig and Geary showed that 21 percent of patients had DIPJ deformity and pain after a six-month follow-up and 50 percent of the 21 percent required further surgical intervention.5 In a study involving 76 patients (100 toes), Lehman and Smith reported deformity of the DIPJ in 44 percent of toes after a PIPJ arthrodesis and patient dissatisfaction with the results due to this new complication and pain.6
In a review of PIPJ resection arthroplasty in 63 patients (118 toes) with an approximate five-year follow-up, Coughlin and colleagues reported 13 percent of patients with presence of hyperextension of the PIPJ and 27 percent of toes lacking ground purchase at the distal digit when patients were standing.7 After an arthroplasty, the digit should be able to maintain some degree of flexion of the PIPJ, thus increasing function of the intrinsic musculature and toe purchase power.6 These results are functionally beneficial and lead to greater patient satisfaction in our experience.
In a 2018 study, Mueller and coworkers assessed 47 patients (76 toes) who had an arthroplasty and a flexor tenotomy.9 The goals of this study were to compare results as well as patient satisfaction between elderly and younger cohorts. They stated that all patients, regardless of age, had significantly improved visual analog pain scores and physical component scores (PCS) at six and 12 months postoperatively. This study suggested that regardless of age or gender, an arthroplasty led to significantly improved outcomes and positive patient results compared to preoperative status.9
When looking at etiologies, we also have a large population of patients, male and female who have acquired hammertoe deformity due to neurologic disorders or diabetic neuropathic changes. These patients have autonomic changes to the musculature that result in muscle imbalance and contracture of the digits. Due to the concern for ulceration, surgical intervention is frequently a recommendation. Though some physicians suggest arthrodesis of neuropathic deformities is superior, we feel strongly that arthroplasty performed with surgical precision will lead to less future ulceration. If arthrodesis results in a rigidly fused lesser toe which lacks sensation, this may easily lead to increased pressure points and new ulceration sites.
A properly performed arthoplasty does take surgical finesse. Over-estimated bony resection may lead to flail toe. As we noted above, O’Kane and Kilmartin found a seven percent risk of flail toe in their study of 100 toes but noted no complaints of future pain or ulceration with such a result.4
Boffeli and Nelson noted that malalignment after arthrodesis is a major factor that can lead to significantly unfavorable results.10 Additionally, once one fuses the PIPJ, there are minimal revision options available to the surgeon. This is in marked contrast to arthroplasty. Even if there is over-resection of bone during an arthroplasty procedure and a subsequent flail toe, the surgeon has the option for revisional arthroplasty with a silicone implant in order to regain height or shift to a final arthrodesis.
Limited exposure, lack of surgeon control over scar tissue, complex muscle anatomy, high stress forces of ambulation and underlying foot structure all lead to chance of recurrence in hammertoe correction.10 One must base the procedure choice on adequate evaluation of all aspects of the case. The best operative plan takes into account multiple variables including age, activity level, patient expectations and precise etiology of the hammertoe deformity.11 We feel strongly that PIPJ arthroplasty is more advantageous than arthrodesis due to retained motion of the joint, natural function of the intrinsic and extrinsic anatomy, cosmesis of the digit and reduction of pain and deformity.
Dr. Randall is a third-year foot and ankle surgery resident at Beaumont Wayne Hospital in Wayne, Mich.
Dr. Fallat is the Podiatric Surgical Residency Director at Beaumont Wayne Hospital in Wayne, Mich. He is a Fellow of the American College of Foot and Ankle Surgeons.
Sharing insights from the literature as well as their surgical experience, these authors maintain that superior biomechanical stability and a variety of fixation options make digital arthrodesis a better choice than arthroplasty.
By Ashim Wadehra, DPM, AACFAS and Andrew Robitaille, DPM
While there are many approaches for hammertoe correction, we contend that arthrodesis is the best approach for surgical treatment of adult hammertoes. Hammertoe deformity is characterized by an extension deformity at the metatarsophalangeal joint (MPJ) and a flexion deformity at the proximal interphalangeal joint (PIPJ). These digital deformities can cause pain, difficulty in shoe gear and an unwanted cosmetic appearance of the toe. Pain can stem from callosities, ulcerations at the level of the MPJ and interphalangeal joints as well as nail deformities.1 Secondary deformities can also develop, including medial or lateral deviation with crossover toe deformity. These digital deformities also present with subluxation or dislocation of the MPJ due to secondary failure of the plantar plate.2
There are many different surgical options offered for the treatment of symptomatic hammertoes. Correction consists of PIPJ arthroplasty or fusion for rigid deformities, and surgeons often combine arthroplasty or fusion with soft tissue procedures such as MPJ capsulotomy, extensor tenotomy/lengthening, flexor release, tendon transfer, metatarsal osteotomy and plantar plate repair.2
Resection arthroplasty is one of the most frequently performed procedures for hammertoe correction but may result in prolonged swelling, shortening of the toe, recurrence and angular deformity. Flexor tendon transfer (Taylor-Girdlestone procedure) can address flexible deformities but can result in interphalangeal stiffness and pose technical difficulty with correct tendon tension post-transfer.2
Researchers have described multiple techniques, including the peg-in-hole technique or end-to-end fusion, to achieve a solid digital arthrodesis with variable fusion rates.2 For many years, the standard fixation technique was the use of a single intramedullary K-wire protruding through the toe. However, today there are many implant options for the surgeon to choose from such as intramedullary implants and screw fixation.
A Closer Look At The Technical And Biomechanical Advantages Of Digital Arthrodesis
A successful fusion of the PIPJ creates a rigid lever arm and converts the pull of the flexor digitorum longus and brevis to flex the MPJ. This pull augments the intrinsic muscles and provides MPJ plantarflexion stability. Arthrodesis also provides triplanar stability to the toe. Proximal interphalangeal joint arthrodesis is also preferable when there are significant deforming forces at play and when there is involvement of multiple digits as the procedure maintains the structural stability to the toes.1
Schrier and colleagues, in a randomized controlled trial, found a significant difference and superiority in sagittal plane alignment with PIPJ fusion compared to arthroplasty.3 They concluded that better alignment in this plane could be especially important as deformity in this plane accounts for most symptoms.3
With an average five-year follow-up, Coughlin and team reported on the results of proximal phalangeal condylectomy, middle phalangeal articular resection and intramedullary K-wire fixation.2 They noted that after resection arthroplasty with intramedullary K-wire fixation, they performed subsequent PIPJ fusion in 81 percent of cases and subjective patient satisfaction was reported in 84 percent of cases.Coughlin and colleagues noted pain relief in 92 percent of the study patients. The authors did not note a difference in pain in those with a fibrous versus a bony union. They go on to state that many reports suggest that a fibrous union is still consistent with a successful outcome.2
Miller and coworkers describe the chevron arthrodesis as a very stable and superior modification to the traditional end-to-end arthrodesis performed by most surgeons.4 They cite excellent cancellous bony contact ensuring a stable arthrodesis without malalignment. The authors also describe triplanar correction with the chevron arthrodesis, especially in the sagittal plane, to be considerably more stable than an end-to-end arthrodesis. One may fixate this chevron arthrodesis hammertoe correction using a K-wire exposed out of the distal toe or the surgeon can elect to create his or her own intramedullary K-wire construct.4
Pertinent Considerations In Hammertoe Fixation
The K-wire has a long standing role as the gold standard for hammertoe repair in both arthrodesis and arthroplasty digital surgery.5 While these wires offer simplistic implementation, they also carry associated risks such as pin tract infection, migration and potential breakage. There is also patient anxiety with a protruding wire, fear of removal and accidental trauma while at home.4
There are also a multitude of internal fixation devices designed for fusion of the PIPJ. The emergence of these devices resulted from the desire of surgeons and patients to avoid the risks and pain associated with percutaneous fixation while also offering long-term stability and correction of the deformity.
In a systematic review, Wei and team found that internal fixation devices as a whole may outperform K-wires in union rate for PIPJ arthrodesis in hammertoe deformity correction.6 However, the authors found no significance in clinical parameters such as pain levels, patient satisfaction, foot-related function or surgical complication rates. Although there could be an increased rate of fusion with the internal fixation devices, this may not compensate for the high price of these devices in comparison to K-wires.6
Our preferred method for correction of hammertoes is arthrodesis using a chevron modification. The superior stability of the construct, reproducibility and patient satisfaction makes it a great procedure in our experience. The senior author fixates with 0.045-inch K-wires and allows them to protrude distally. The senior author also performs a flexor tendon transfer to help mitigate any residual extension of the toe, especially if there is plantar plate pathology. A simple way to ease patient anxiety associated with the exposed pins is to hide them by covering the toes in gauze and Coban.
Successful foot and ankle surgery depends on addressing all levels of deformity with consideration of biomechanical factors. For these reasons, it is our opinion that PIPJ arthrodesis is the superior procedure. With digital arthrodesis, there are many fixation options ranging from simple K-wires to cannulated screws and other internal fixation devices. It is the responsibility of the surgeon to select the most appropriate approach for each patient.
Dr. Wadehra is fellowship-trained foot and ankle surgeon in private practice in Dearborn Heights, Mich. He is an Associate of the American College of Foot and Ankle Surgeons.
Dr. Robitaille is a second-year foot and ankle surgery resident at Beaumont Hospital Wayne in Wayne. Mich.
1. Atinga M, Dodd L, Foote J, Palmer S. Prospective review of medium term outcomes following interpositional arthroplasty for hammer toe deformity correction. Foot Ankle Surg. 2011;17(4):256-258.
2. Coughlin MJ. Lesser-toe abnormalities. J Bone Joint Surg. 2002;84(8):1446-1469.
3. Ellington JK. Hammertoes and clawtoes: proximal interphalangeal joint correction. Foot Ankle Clin. 2011;16(4):547-558.
4. O’Kane C, Kilmartin T. Review of proximal interphalangeal joint excisional arthroplasty for the correction of second hammer toe deformity in 100 cases. Foot Ankle Int. 2005;26(4):320- 325.
5. Baig AU, Geary NPJ. Fusion rate and patient satisfaction in proximal interphalangeal joint fusion of the minor toes using Kirschner wire fixation. Foot. 1996;6(3):120-121.
6. Lehman DE, Smith RW. Treatment of symptomatic hammertoe with a proximal interphalangeal joint arthrodesis. Foot Ankle Int. 1995;16(9):535-541.
7. Coughlin MJ, Dorris J, Polk E. Operative repair of the fixed hammertoe deformity. Foot Ankle Int. 2000;21(2):94-104.
8. Ohm 2nd OW, McDonell M, Vetter WA. Digital arthrodesis: an alternate method for correction of hammer toe deformity. J Foot Ankle Surg. 1990;29(3):207-211.
9. Mueller CM, Boden SA, Boden AL, et al. Complication rates and short-term outcomes after operative hammertoe correction in older patients. Foot Ankle Int. 2018;39(6):681-688.
10. Boffeli TJ, Nelson GD. How to address recurrent hammertoes. Podiatry Today. 2020;33(10):26-32.
11. Kernbach KJ. Hammertoe surgery: arthroplasty, arthrodesis or plantar plate repair? Clin Podiatr Med Surg. 2012;29(3):355-366.
1. Lehman DE, Smith RW. Treatment of symptomatic hammertoe with a proximal interphalangeal joint arthrodesis. Foot Ankle Int. 1995;16(9):535-541.
2. Coughlin MJ, Dorris J, Polk E. Operative repair of the fixed hammertoe deformity. Foot Ankle Int. 2000;21(2):94-104.
3. Schrier JC, Keijsers NL, Matricali GA, Louwerens JWK, Verheyen CPM. Lesser toe PIP joint resection versus PIP joint fusion: a randomized clinical trial. Foot Ankle Int. 2016;37(6):569–575.
4. Miller JM, Blacklidge DK, Ferdowsian V, Collman DR. Chevron arthrodesis of the interphalangeal joint for hammertoe correction. J Foot Ankle Surg. 2010;49(2):194-196.
5. Kramer WC, Parman M, Marks RM. Hammertoe correction With K-wire fixation. Foot Ankle Int. 2015;36(5):494-502.
6. Wei RX, Ling SK, Lui TH, Yung PS. Ideal implant choice for proximal interphalangeal joint arthrodesis in hammer toe/claw toe deformity correction: A systematic review. J Orthop Surg (Hong Kong). 2020;28(1): 2309499020911168.