Using a bone allograft to fixate proximal interphalangeal joint arthrodesis

Fiber-reinforced fixation implant for proximal interphalangeal joint arthrodesis shows implant bio-integration at 1-year follow-up

BACKGROUND

A new bio-integrative fiber-reinforced implant (OSSIOfiber® Hammertoe Fixation Implant, OSSIO Ltd., Caesarea, Israel) was developed for proximal interphalangeal joint (PIPJ) correction-arthrodesis. The main purpose of this clinical study was to assess implant bio-integration at 1-year follow-up.

METHODS

Twenty-four patients, previously treated for a Hammertoe deformity using the bio-integrative, fiber-reinforced implant, were enrolled in this follow-up study. One-year follow-up included clinical examination, patient reported outcomes, radiographs, Magnetic Resonance Imaging (MRI) and bio-integration scoring.

RESULTS

Proximal interphalangeal joint (PIPJ) radiographic fusion rate was 92% (n = 22). MRI was analyzed for 24 (100%) patients. In 100% of patients (n = 24), the border between implant and surrounding tissue was scored as partially visible. There were no cyst formation or fluid accumulation findings. Mild bone edema was detected in 29% (n = 7) and is attributed to the chronic distribution of forces due to chronic abnormal gait and pasture. None of the edema findings were considered as adverse implant-related finding. The mean bio-integration score was 7.71 ± 0.46.

CONCLUSIONS

This study demonstrates safe bio-integration of the newly developed fiber-reinforced implant at 1-year follow-up without negative side effects.

Ideal implant choice for proximal interphalangeal joint arthrodesis in hammer toe/claw toe deformity correction: A systematic review

Intramedullary devices have been developed to reduce the problems associated with Kirschner (K)-wire fixation in proximal interphalangeal joint (PIPJ) arthrodesis. The purpose of this systematic review is to compare the surgical outcomes of K-wires versus novel internal fixation devices in PIPJ arthrodesis in claw/hammer toe surgery. The databases searched were PubMed, Scopus, Cochrane, and Embase with keywords "claw toe OR hammer toe" AND "proximal interphalangeal OR PIP" AND "fusion OR arthrodesis." Clinical trials published in English with evidence levels I, II, and III were included. Five studies, including one randomized controlled trial and four case-controlled studies, were identified to meet the inclusion criteria. Overall, the studies showed promising results in union rates using the novel internal devices compared to K-wires. However, the novel internal devices seem not to present advantages in clinical parameters such as pain levels, patient satisfaction, foot-related function, or surgical complication rates.

Prospective, Multicenter, Clinical and Radiographic Evaluation of a Biointegrative, Fiber-Reinforced Implant for Proximal Interphalangeal Joint Arthrodesis

Background:

A novel biointegrative implant was developed for proximal interphalangeal joint (PIPJ) arthrodesis to treat hammertoe deformity. Composed of continuous reinforcing mineral fibers bound by bioabsorbable polymer matrix, the implant demonstrated quiescent, gradual degradation with complete elimination at 104 weeks in animal models. This prospective trial assessed the implant’s safety, clinical performance, and fusion rate of PIPJ arthrodesis for hammertoe correction.

Methods:

Twenty-five patients (mean age 63.9±7.5 years) who required PIPJ arthrodesis were enrolled at 3 centers. Outcomes included radiographic joint fusion, adverse events, pain visual analog scale (VAS) score, Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) score, and patient satisfaction. Patients were evaluated 2, 4, 6, 12, and 26 weeks postoperatively.

Results:

Twenty-two patients (88%) achieved radiographic fusion at 26 weeks. All joints (100%) were considered clinically stable, with no complications or serious adverse events. Pain VAS improved from 5.3±2.5 preoperatively to 0.5±1.4 at 26 weeks postoperatively. FAAM-ADL total scores and level of functioning improved by mean 19.5±19.0 points and 24.4±15.7 percentage points, respectively, from preoperation to 26 weeks postoperation. Improvements in pain VAS and FAAM scores surpassed established minimal clinically important differences. All patients were very satisfied (84%) or satisfied (16%) with the surgery. Patient-reported postoperative results greatly exceeded (72%), exceeded (20%), or matched (8%) expectations.

Conclusion:

This prospective, multicenter, first-in-human clinical trial of a novel biointegrative fiber-reinforced implant in PIPJ arthrodesis of hammertoe deformity demonstrated a favorable rate of radiographic fusion at 12 and 26 weeks, with no complications and good patient-reported clinical outcomes.

Level of Evidence:

Level IV, prospective case series.

[Research progress of interphalangeal arthrodesis]

Objective

To review the research progress of interphalangeal arthrodesis in the treatment of interphalangeal joint deformity.

Methods

The literature about interphalangeal arthrodesis at home and abroad was extensively consulted, and the indications, fusion methods, fixation methods, complications, and so on were summarized and analysed.

Results

The indications of interphalangeal arthrodesis are hammer toe, claw toe, and mallet toe. From the different forms of fusion surface, fusion methods include end-to-end, peg-in-hole, conical reamer type, and V-shape arthrodesis. There are three kinds of fixation methods: Kirschner wire fixation, stainless-steel wire suture fixation, and intramedullary fixation, and there are many kinds of intramedullary fixation. The complications of interphalangeal arthrodesis include vascular injury, fixation related complications, and postoperative complications.

Conclusion

Interphalangeal arthrodesis is a good way to correct some deformities of toes, but the incidence of various complications can not be ignored, and there is still a lack of clinical research on interphalangeal arthrodesis.

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.

Proximal Interphalangeal Arthrodesis of Lesser Toes Utilizing K-Wires Versus Expanding Implants: Comparative Biomechanical Cadaveric Study

BACKGROUND:

Lesser toe proximal interphalangeal (PIP) joint arthrodesis is one of the most common foot and ankle elective procedures often using K-wires for fixation. K-wire associated complications led to development of intramedullary fixation devices. We hypothesized that X Fuse (Stryker) and Smart Toe (Stryker) would provide stronger and stiffer fixation than K-wire fixation.

METHODS:

12 cadaveric second toe pairs were used. In one group, K-wires stabilized 6 PIP joints, and 6 contralateral PIP joints were fixed with X Fuse. A second group used K-wires to stabilize 6 PIP joints, and 6 contralateral PIP joints were fixed with Smart Toe. Specimens were loaded cyclically with extension bending using 2-N step increases (10 cycles per step). Load to failure and initial stiffness were assessed. Statistical analysis used paired t tests.

RESULTS:

K-wire average failure force, 91.0 N (SD 28.3), was significantly greater than X Fuse, 63.3 N (SD 12.9) ( P < .01). K-wire average failure force, 102.3 N (SD 17.7), was also significantly greater than Smart Toe, 53.3 N (SD 18.7) ( P < .01). K-wire initial stiffness 21.3 N/mm (SD 5.7) was greater than Smart Toe 14.4 N/mm (SD 9.3) ( P = .02). K-wire failure resulted from bending of K-wire or breaching cortical bone. X Fuse typically failed by implant pullout. Smart Toe failure resulted from breaching cortical bone.

CONCLUSION:

K-wires may provide stiffer and stronger constructs in extension bending than the X Fuse or Smart Toe system. This cadaver study assessed stability of the fusion site at time zero after surgery.

CLINICAL RELEVANCE:

Our findings provide new data supporting biomechanical stability of K-wires for lesser toe PIP arthrodesis, at least in this clinically relevant mode of cyclic loading.

Comparative Study of Intramedullary Hammertoe Fixation

BACKGROUND

Temporary Kirschner wire fixation (K-wire) is a widely used, low-cost fixation method for the correction of hammertoe deformity. Reported complications associated with K-wires prompted the development of new implants over the past decade. However, there is a lack of literature on comparative studies analyzing functional outcomes using validated questionnaires. The purpose of this study was to analyze functional outcomes in patients who had undergone proximal interphalangeal joint fusion using 2 types of intramedullary implant, the Smart Toe and the TenFuse, and to compare them with the outcomes in patients treated with standard K-wire fixation.

METHODS

A retrospective review of operative hammertoe correction by a single surgeon was performed in 96 patients followed for more than 12 months. Functional outcome was assessed using the Foot Function Index (FFI), the Short Form 36 (SF-36), and the 10-point visual analog scale (VAS) validated questionnaires. Complications and fusion rates were also evaluated. Several patients in the study underwent corrections in different toes; thus, a total of 186 toes were included in the study. From these, 65 toes (34.9%) were treated with K-wire fixation, 94 (50.5%) with Smart Toe titanium implant, and 27 (14.5%) with TenFuse allograft implant.

RESULTS

No statistically significant differences in functional outcome and incidence of complications were observed among the 3 fixation groups, although the 2 intramedullary implants were associated with greater fusion rates and patient satisfaction. Breakage of the Smart Toe implant was significantly higher than that of the other fixations, with 10.6% of implants breaking within the first year postoperatively. SF-36 and VAS scores decreased 12 months after surgery for the 3 types of fixation, with no statistically significant differences observed.

CONCLUSION

The use of Smart Toe and TenFuse implants provided operative outcomes comparable to those obtained using a K-wire fixation and slightly better patient satisfaction. Our results suggest that utilization of these implants for hammertoe correction was a reasonable choice that provided good alignment, pain reduction, and improved function at final follow-up. However, they are more expensive than K-wires. For this reason, in-depth cost-benefit studies would be required to justify their use as a standard treatment.

LEVEL OF EVIDENCE

Level III, comparative series.

Bioabsorbable Fixation Screw for Proximal Interphalangeal Arthrodesis of Lesser Toe Deformities

BACKGROUND

Although standard fixation of proximal interphalangeal (PIP) arthrodesis by K-wire is relatively inexpensive and well established, it does have some drawbacks, making newer fixation devices interesting. The aim of this study was to clinically and radiologically assess the operative correction of the lesser toe deformation in the form of a PIP arthrodesis using a bioabsorbable 2.7-mm fixation screw.

METHODS

From January 2011 until October 2013, 34 patients underwent a PIP arthrodesis using the TRIM-IT (Arthrex) 2.7-mm fixation screw and were contacted for this retrospective cohort study. At an average of 3.3 years after the operation, 24 patients and 26 toes were evaluated clinically, radiologically, through pedobarography, and a patient-satisfaction survey.

RESULTS

Using the PLLA screw for fixation, 84.6% showed bony union of the arthrodesis, and 84.6% were satisfied. Mean AOFAS score was 82.7 points and thus regarded as good. The mean VAS score was 1.3/10. Overall, 73.1% of the toes showed good alignment, and 7.7% had a painless recurrence of deformity and were still satisfied with the intervention. In addition, 34.6% had floating toes, but only 4.2% without Weil osteotomy or encroachment. Further, 3.8% were advised to undergo a revision because of severe misalignment.

CONCLUSION

The 2.7-mm bioabsorbable fixation screw yielded results that were comparable to other fixation devices for PIP fusion fixation regarding success rate, revisions, and patient acceptance.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Digital Arthrodesis of the Lesser Toes

Foot and ankle surgeons frequently treat digital deformities of the lesser toes surgically. Arthrodesis of the proximal interphalangeal joint is the workhorse procedure for correction of hammer toe contractures. Fusion of the interphalangeal joint can be fixated with a variety of methods, including K-wire fixation, intramedullary implants, absorbable pins, and screws. Each method of fixation has advantages and disadvantages, such as variations in complication rates, cost, and fusion rates. Further research is necessary to determine the best method of fixation for digital interphalangeal joint fusion."

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/m(2), 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.

Hammertoe correction with k-wire fixation

BACKGROUND

Kirschner wire (K-wire) fixation for correction of hammertoe deformity is a common, low-cost method for fixation of hammertoes after proximal interphalangeal (PIP) arthroplasty or fusion. Complications of this procedure include pin-tract infection, pin migration, pin bending or breakage, and recurrence of deformity. The investigators reviewed a large experience using K-wire stabilization for hammertoe correction.

METHODS

All hammertoe corrections performed by a single surgeon from 1999 to 2013 were retrospectively reviewed. A resection arthroplasty of the PIP joint or PIP fusion was performed and fixed with a K-wire. Follow-up duration, preoperative diagnosis, pin duration, concomitant procedures, recurrence rates, and complications were reviewed and analyzed. A total of 1,115 operations were performed on 876 patients, with correction of 2,698 hammertoes. There were 709 female and 167 male patients, with an average age of 57.5 years (range, 14-88 years), followed for an average of 20.8 months (range, 27 days to 12.7 years).

RESULTS

Complications included 94 pin migrations (3.5%), 9 pin-tract infections (0.3%), and 2 pin breakages (0.1%). There were 150 recurrent deformities (5.6%) and 94 toes (3.5%) required revision hammertoe surgery. Malalignment was noted in 55 toes (2.1%). Vascular compromise occurred in 16 toes (0.6%), with 10 (0.4%) requiring amputation. Ninety-four toes (3.5%) required revision surgery because of symptomatic recurrence of deformity. The expected rates and rate ratios (RRs) of patients requiring revision hammertoe correction, compared with the study population as a whole, were statistically significantly higher in patients who underwent an metatarsophalangeal joint capsulotomy (3.10 vs 0.97; RR, 3.20) and those who experienced K-wire-related complications (5.10 vs 1.80, RR, 2.84).

CONCLUSIONS

K-wire fixation for the treatment of hammertoe deformities led to good maintenance of correction with a relatively low complication rate, and we believe that it remains an effective, low-cost method of fixation for hammertoe correction.

LEVEL OF EVIDENCE

Level IV, retrospective case series.