Digital arthrodesis: current fixation techniques

Patient-Reported Outcome Measurement Information System Measures for Proximal Interphalangeal Joint Arthrodesis in Lesser Toe Deformities

Although hammertoe (HT) is a common complaint among foot patients, there is little consensus on the best surgical approach for correction. These authors hypothesized that the use of a headless intramedullary screw across both the proximal interphalangeal joint (PIPJ) and distal interphalangeal joint (DIPJ) would decrease many post-surgical complications, such as infection, pain, and mallet toe deformity, found in traditional HT corrective surgical techniques. In this retrospective cohort study, N = 163 adult patients who had undergone DIPJ/PIPJ arthrodesis for HT correction at least 1 year prior to the study were identified. One hundred fifty-nine patients were contacted through REDCap to complete Patient-Reported Outcome Measurement Information System (PROMIS) physical function (PF) and pain interference (PI). Demographic, radiographic, and follow-up data were taken from the electronic medical record (EMR). Analysis was completed with Microsoft Excel; PROMIS PF and PI measures for the 32-person cohort were 45.65 ± 8.26 and 51.65 ± 9.01, respectively. The PF and PI measures had a statistically significant correlation (R2 = 0.71). The 163-person cohort had an overall revision rate of 6.75%, or 11 patients, and an infection rate of 1.23%. This procedure had lower rates of residual pain, infection, mallet toe deformity, and reoperation when compared with current techniques. This study supports the safety and viability of PIPJ/DIPJ arthrodesis using a headless screw for HT correction.Levels of Evidence: Level III Retrospective Cohort Study.

Novel Extramedullary Fixation Device for Hammertoe Correction: A Retrospective Review of 100 patients

Classically, one of the more common treatment options for rigid hammertoe correction consists of end-to-end arthrodesis stabilized by temporary Kirschner wire (K-wire) fixation maintained until osseous consolidation or complication necessitating premature removal. However, single K-wire fixation allows for axial rotation which results in loss of compression at the arthrodesis site. To counteract this, intramedullary implants were designed to provide fusion site stability in all planes negating extra-skeletal extension of the wire. Nevertheless, manual pressfit implants arguably offer less reliable positioning of the fusion site in a true end to end orientation due to variation in intramedullary stem placement compared to direct visualization with dorsal plating. Larger diameter implants create an osseous void at the bony interface reducing the potential of true bony union. Hammertoe implant failure poses a unique and challenging salvage scenario which can ultimately end in amputation. Extramedullary fixation is uniquely designed to merge both benefits of K-wires and intramedullary implants while eliminating inadequacies of each. A total of 100 patients who underwent 150 rigid hammertoe corrections with an extramedullary implant were retrospectively reviewed. The mean postoperative follow-up was 12.6 months (range 12-18 months). Overall, 94 of 100 patients (94%) achieved radiographic union, defined by 2 or more bridged cortices at the arthrodesis site without signs of hardware breakage or signs of lucency across one or more fusion sites at a mean 8.8 weeks (range 7-10 weeks). This study demonstrated excellent results in regards to postoperative arthrodesis when utilizing an extramedullary implant for hammertoe deformity correction. This device minimizes osseous deficit by extramedullary application, all while augmenting intramedullary K-wire fixation.

The efficacy of an intramedullary nitinol implant in the correction of claw toe or hammertoe deformities

INTRODUCTION

A multitude of procedures has been described in the literature for the treatment of lesser toe deformities and there is currently no general consensus on the optimal method of fixation. The aim of this study is to assess the clinical and radiological outcomes of an intramedullary nitinol implant for the correction of lesser toe deformities, and to determine if the distal interphalangeal (DIP) joint and metatarsophalangeal (MTP) joint are modified during patient follow-up after correction of the PIP joint.

MATERIALS AND METHODS

A prospective analysis of 36 patients with claw toe or hammertoe who were treated with an intramedullary nitinol implant. Clinical manifestations and angulation of the metatarsophalangeal, proximal and distal interphalangeal (MTP, PIP, DIP) joints were evaluated in radiographic studies preoperatively, at first medical revision post-surgery, and after a minimum of 1 year of follow-up. Complications such as non-union rate, implant rupture, and implant infection were also evaluated during follow-up.

RESULTS

All patients were women with an average age of 65.5 (range 47-82) years. The average follow-up time was 2.4 (range 1-5.7) years. Fifty intramedullary nitinol implants were used. The MTP joint extension and PIP joint flexion decreased by 15.9° (95% CI - 19.11 to - 12.63) and 49.4° (95% CI - 55.29 to - 43.52), respectively, at the end of follow-up. Moreover, the DIP joint flexion increased progressively during follow-up (13.7° pre-surgery versus 35.6 in last medical check-up, 95% CI 13.24-30.57). There were four (8%) asymptomatic implant ruptures. The rate of fusion was 98%.

CONCLUSION

The reduction of the PIP joint using an intramedullary nitinol implant is a good option in lesser toe deformities, with few complications and a high rate of arthrodesis. Moreover, the PIP joint reduction affects both the MTP and DIP joints.

Percutaneous Kirschner Wire Versus Commercial Implant for Hammertoe Repair: A Cost-Effectiveness Analysis

Hammertoe deformities are one of the most common foot deformities, affecting up to one third of the general population. Fusion of the joint can be achieved with various devices, with the current focus on percutaneous Kirschner (K)-wire fixation or commercial intramedullary implant devices. The purpose of the present study was to determine whether surgical intervention with percutaneous K-wire fixation versus commercial intramedullary implant is more cost effective for proximal interphalangeal joint arthrodesis in hammertoe surgery. A formal cost-effectiveness analysis using a decision analytic tree model was conducted to investigate the healthcare costs and outcomes associated with either K-wire or commercial intramedullary implant fixation. The outcomes assessed included long-term costs, quality-adjusted life-years (QALYs), and incremental cost per QALY gained. Costs were evaluated from the healthcare system perspective and are expressed in U.S. dollars at a 2017 price base. Our results found that commercial implants were minimally more effective than K-wires but carried significantly higher costs. The total cost for treatment with percutaneous K-wire fixation was $5041 with an effectiveness of 0.82 QALY compared with a commercial implant cost of $6059 with an effectiveness of 0.83 QALY. The incremental cost-effectiveness ratio of commercial implants was $146,667. With an incremental cost-effectiveness ratio of >$50,000, commercial implants failed to justify their proposed benefits to outweigh their cost compared to percutaneous K-wire fixation. In conclusion, percutaneous K-wire fixation would be preferred for arthrodesis of the proximal interphalangeal joint for hammertoes from a healthcare system perspective.

Two-Pin Fixation of Proximal Interphalangeal Joint Fusion for Hammertoe Correction

Single-pin external Kirschner wire (K-wire) fixation has traditionally been a mainstay in proximal interphalangeal joint fusion for central hammertoe repair. Concerns over cosmesis, inconvenience, pin tract infection, hardware failure, nonunion, and early hardware removal have led to the development of implantable internal fixation devices. Although numerous implantable devices are now available and represent viable options for hammertoe repair, they are costly and often pose a challenge in the event removal becomes necessary. An alternative fixation option not typically used is a 2-pin K-wire fixation technique. The perceived advantage of obtaining 2 points of fixation compared with 1 across the fusion site is improved stability against the rotational and bending forces, thus decreasing the potential for pin-related complications. A retrospective assessment of 91 consecutive hammertoe repairs consisting of proximal interphalangeal joint fusion with 2-pin fixation in 60 patients was performed. The K-wires were removed at 6 weeks postoperatively, and the overall postoperative follow-up duration was 28.56 (range 1.40 to 86.83) months. Of the 91 digits, 89 (98%) did not encounter a complication postoperatively and 2 (2.20%) had sustained loosened or broken hardware. No postoperative infection was encountered. The low incidence of complications observed supports the 2-pin K-wire fixation technique as a low-cost and viable construct for proximal interphalangeal joint fusion hammertoe repair.

Use of Smart Toe(©) implant for small toe arthrodesis: A smart concept?

BACKGROUND

Arthrodesis of small joints for hammer and claw toe deformities is a common forefoot operative procedure. Our objective was to review patients who underwent small toe arthrodesis with Smart Toe(©) intramedullary monobloc implant. Our aim was to assess patient's surgical outcome and to ascertain implant suitability.

METHODS

This procedure was undertaken in 90 patients from February 2011 to December 2012. We present our review of 82 (91.1%) patients who attended the final six 6-month follow up. Mean age was 56.5 years. There were 7 (8.5%) males and 75 (8.5%) males and 75 (91.5%) females. Clinical and radiological evaluation was undertaken. A questionnaire was used to assess general symptoms, clinical outlook, deformity and patient's perceptions and acceptance. Foot and Ankle Outcome Score and Foot and Ankle Disability Index were used to judge outcome.

RESULTS

There were 71 (86.6%) proximal and 11 (13.4%) distal interphalangeal joints with 69 (84.1%) second, 7 (8.5%) third, 6 (84.1%) second, 7 (8.5%) third, 6 (7.3%) fourth toes. There was persistent swelling in 7 (8.5%) and tenderness in 1 (1.2%). Appearance of toes was symmetrical in 71 (86.6%) and 11 (13.4%) were asymmetrical but asymptomatic. The mean range of movement of the adjacent joint was 53.9°. Control of toes was good in 72 (87.8%) patients. Mean percentage of improvement was 76.1% with 100% in 17 (20.7%) and over 80% in 47 (57.3%). Seventy (85.3%) would recommend and undergo repeat surgery. There were 2 (2.4%) cases of metal cut out. There was one (1.2%) implant failure. Union was achieved in 79 (96.3%) patients.

CONCLUSION

We feel that Smart Toe(©) small toe arthrodesis is a safe and reliable technique with good patient outcome and acceptance.

A simple method of intramedullary fixation for proximal interphalangeal arthrodesis

Lesser digital arthrodesis has become one of the most widely used techniques in foot and ankle surgery. When performing digital arthrodesis, surgeons have an abundance of options for implantable devices. We provide information on a simple method of achieving successful arthrodesis. An intramedullary Kirschner wire is implanted into the proximal phalanx with the intermediate phalanx compressed over the wire for rigid internal fixation to avoid the use of an external device. We have had results similar to those from the published data of more expensive implants.