Dual-Component Intramedullary Implant Versus Kirschner Wire for Proximal Interphalangeal Joint Fusion: A Randomized Controlled Clinical Trial


      We undertook a multicenter, parallel treatment arm, randomized controlled trial to compare the outcomes after surgery for the treatment of lesser digital hammertoe using either a Kirschner wire or a 2-piece intramedullary, stainless steel implant for fixation of the proximal interphalangeal joint. Our primary aim was to compare the incidence of arthrodesis and complications, and our secondary aim was to compare the subjective foot-related outcomes measured using the Bristol Foot Score and the Foot Function Index, stratified by fixation group. We hypothesized that the use of the dual-component implant would result in greater patient satisfaction, a greater incidence of radiographic arthrodesis, and fewer complications after hammertoe repair. The overall mean age of the participants was 58.72 ± 13.48 (range 18 to 84) years, their mean body mass index was 30.14 ± 6.55 (range 20.7 to 46.98) kg/m2, and no statistically significant differences in the demographic variables were present between the treatment groups at baseline or during the follow-up period. Of the 91 participants, 46 (50.55%) were randomly allocated to the Kirschner wire group and 45 (49.45%) to the intramedullary implant group. No statistically significant differences were observed between the 2 fixation groups in the incidence of complications; however, the 2-piece intramedullary implant group was associated with a greater mean Bristol Foot Score and Foot Function Index score and a greater incidence of fusion.

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        • Dunn J.E.
        • Link C.L.
        • Felson D.T.
        • Crincoli M.G.
        • Keysor J.J.
        • McKinlay J.B.
        Prevalence of foot and ankle conditions in a multiethnic community sample of older adults.
        Am J Epidemiol. 2004; 59: 491-498
        • Holewski J.J.
        • Moss K.M.
        • Stess R.M.
        • Graf P.M.
        • Grunfeld C.
        Prevalence of foot pathology and lower extremity complications in a diabetic outpatient clinic.
        J Rehabil Res Devlop. 1989; 26: 35-44
        • Myerson M.S.
        • Shereff M.J.
        The pathological anatomy of claw and hammertoes.
        J Bone Joint Surg Am. 1989; 71: 45-49
        • Sarrafian S.K.
        • Topouzian L.K.
        Anatomy and physiology of the extensor apparatus of the toes.
        J Bone Joint Surg Am. 1969; 51: 669-679
        • Co A.Y.
        • Ruch J.A.
        • Malay D.S.
        Radiographic analysis of transverse plane digital alignment after surgical repair of the second metatarsophalangeal joint.
        J Foot Ankle Surg. 2006; 45: 380-399
        • Galli M.M.
        • Brigido S.A.
        • Protzman N.M.
        Pinning across the metatarsophalangeal joint for hammertoe correction: where are we aiming and what is the damage to the metatarsal articular surface?.
        J Foot Ankle Surg. 2014; 53: 405-410
        • Boffeli T.J.
        • Thompson J.C.
        • Tabatt J.A.
        Two-pin fixation of proximal interphalangeal joint fusion for hammertoe correction.
        J Foot Ankle Surg. 2016; (Epub 2016 Feb 12)
        • Dayton P.
        • Smith D.
        Dorsal suspension stitch: an alternative stabilization after flexor tenotomy for flexible hammer digit syndrome.
        J Foot Ankle Surg. 2009; 48: 602-605
        • Canales M.B.
        • Razzante M.C.
        • Ehredt D.J.
        • Clougherty C.O.
        A simple method of intramedullary fixation for proximal interphalangeal arthrodesis.
        J Foot Ankle Surg. 2014; 53: 817-824
        • Harris W.
        • Mote G.
        • Malay D.S.
        Fixation of the proximal interphalangeal arthrodesis with the use of an intraosseous loop of stainless-steel wire suture.
        J Foot Ankle Surg. 2009; 48: 411-414
        • Andirasa A.K.
        • Barrett M.J.
        • Silvester D.
        SmartToe® implant compared with Kirschner wire fixation for hammer digit corrective surgery: a review of 28 patients.
        J Foot Ankle Surg. 2012; 51: 711-713
        • Scholl A.
        • McCarty J.
        • Scholl D.
        • Mar A.
        Smart Toe® implant versus buried Kirschner wire for proximal interphalangeal joint arthrodesis: a comparative study.
        J Foot Ankle Surg. 2013; 52: 580-583
        • Catena F.
        • Doty J.F.
        • Jastifer J.
        • Coughlin M.J.
        • Stevens F.
        Prospective study of hammertoe correction with an intramedullary implant.
        Foot Ankle Int. 2014; 35: 319-325
        • Roukis T.S.
        A 1-piece shape-metal nitinol intramedullary internal fixation device for arthrodesis of the proximal interphalangeal joint in neuropathic patients with diabetes.
        Foot Ankle Spec. 2009; 2: 130-134
        • Witt B.L.
        • Hyer C.F.
        Treatment of hammertoe deformity using a one-piece intramedullary device: a case series.
        J Foot Ankle Surg. 2012; 51: 450-456
        • Kominsky S.J.
        • Bermudez R.
        • Bannerjee A.
        Using a bone allograft to fixate proximal interphalangeal joint arthrodesis.
        Foot Ankle Spec. 2013; 6: 132-136
        • Joseph R.
        • Schroeder K.
        • Greenberg M.
        A retrospective analysis of lesser metatarsophalangeal joint fusion as a treatment option for hammertoe pathology associated with metatarsophalangeal joint instability.
        J Foot Ankle Surg. 2012; 51: 57-62
        • 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: 320-325
        • Matsumoto T.
        • Kadono Y.
        • Nishino J.
        • Nakamura K.
        • Tanaka S.
        • Yasui T.
        Midterm results of resection arthroplasty for forefoot deformities in patients with rheumatoid arthritis and the risk factors associated with patient dissatisfaction.
        J Foot Ankle Surg. 2014; 53: 41-46
        • Borchgrevink G.E.
        • Finsen V.
        Tidsskr Nor Laegeforen. 2010; 4: 2116-2118
        • Bauman M.L.
        • Steiner I.
        • Mandresh R.S.
        • Green D.R.
        Bone regeneration in digital surgery.
        J Am Podiatry Assoc. 1981; 71: 430-435
        • Ellington J.K.
        • Anderson R.
        • Davis H.
        • Cohen B.
        • Jones C.
        Radiographic outcomes following proximal interphalangeal joint arthrodesis with an intramedullary fusion device for lesser toe deformities.
        Foot Ankle Int. 2010; 31: 372-376
        • Zelen C.M.
        • Young N.J.
        Digital arthrodesis.
        Clin Podiatr Med Surg. 2013; 30: 271-282
        • Klammer G.
        • Baumann G.
        • Moor B.K.
        • Farshad M.
        • Espinosa N.
        Early complications and recurrence rates after Kirschner wire transfixion of lesser toe surgery: a prospective randomized study.
        Foot Ankle Int. 2012; 33: 105
        • Femino J.E.
        • Mueller K.
        Complications of lesser toe surgery.
        Clin Orthop Relat Res. 2001; 391: 72-88
        • Karlock L.G.
        Second metatarsophalangeal joint fusion: a new technique for crossover hammertoe deformity: a preliminary report.
        J Foot Ankle Surg. 2003; 42: 178-182
        • Ellington J.K.
        • Anderson R.B.
        • Davis W.H.
        • Cohen B.E.
        • Jones C.P.
        Radiographic analysis of proximal interphalangeal joint arthrodesis with an intramedullary fusion device for lesser toe deformities.
        Foot Ankle Int. 2010; 31: 372-376
        • Barnett S.
        • Campbell R.
        • Harvey I.
        The Bristol foot score: developing a patient-based foot-health measure.
        J Am Podiatr Med Assoc. 2005; 95: 264-272
        • Budiman-Mak E.
        • Conrad K.J.
        • Roach K.E.
        The foot function index: a measure of foot pain and disability.
        J Clin Epidemiol. 1991; 44: 561-570
        • Sun K.
        • Song J.
        • Manheim L.M.
        • Chang R.W.
        • Kwoh K.C.
        • Semanik P.A.
        • Eaton C.B.
        • Dunlop D.D.
        Relationship of meeting physical activity guidelines with quality-adjusted life-years.
        Semin Arthritis Rheum. 2014; 44: 264-270
        • McGuire K.J.
        • Chacko A.T.
        • Bernstein J.
        Cost-effectiveness of teaching hospitals for the operative management of hip fractures.
        Orthopedics. 2011; 34: e598-e601