Silicone arthroplasty versus screw arthrodesis in distal interphalangeal joint osteoarthritis

The aim of this study was to evaluate patient satisfaction after distal interphalangeal joint silicone arthroplasty and compare this outcome to that achieved with screw arthrodesis. On average 4.4 years after surgery, range of motion of the distal interphalangeal joint, pain on a numeric rating scale, satisfaction, and hand appearance of 48 patients (78 treated fingers) were assessed. For arthroplasty patients, mean distal interphalangeal joint motion was 28° with an extension deficit of 17°. Pain was low for arthroplasty and arthrodesis patients with scores of 0.2 and 0.6 out of a total of 10 points, respectively. The patients in both groups were satisfied with their outcomes, but arthroplasty patients were less satisfied with the appearance. Twenty-one per cent of the arthroplasties and 15% of the arthrodeses underwent reoperation. We suggest the motion-preserving distal interphalangeal arthroplasty as an alternative to distal interphalangeal arthrodesis for patients with higher functional demands and whose joints are stable preoperatively. In patients attaching importance to hand aesthetics and for unstable joints, distal interphalangeal joint arthrodesis is preferable. Level of evidence: III

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.

Hallux Interphalangeal Arthrodesis Following First Metatarsophalangeal Arthrodesis

Background: Hallux interphalangeal (IP) arthritis can occur after first metatarsophalangeal (MTP) arthrodesis. IP arthrodesis is a standard treatment, but in the setting of prior MTP surgery there will be increased stress on the IP joint. This may result in diminished potential for bone healing. This investigation assessed the outcomes of hallux IP arthrodesis after first MTP arthrodesis. Methods: Charts were retrospectively reviewed for patients who underwent interphalangeal arthrodesis between January 1, 2007, and April 3, 2017, and who had a minimum of 12 weeks of follow-up. We compared patients with and without prior ipsilateral first MTP arthrodesis. There were 42 patients whose median follow-up was 9 (range, 3-135) months. Results: Median time from previous first MTP arthrodesis until IP arthrodesis was 54 months. Six nonunions (35.3%) occurred in 17 patients with prior first MTP arthrodesis. Only 2 nonunions (8.0%) occurred in 25 patients with isolated IP arthrodesis. The multivariable risk difference of nonunion was 53.3% ( P = .001). Prior first MTP arthrodesis also was more likely to have complications (52.9% vs 24.0%, respectively). The multivariable risk difference of complications was 35.7% ( P = .082). The speed of bone healing was significantly different, with a multivariable rate ratio of 0.21 ( P = .012). Conclusion Prior first MTP arthrodesis resulted in 4.8 times slower bone healing for IP arthrodesis. It increased the risks of nonunion and any other complications. Level of Evidence: Level III, retrospective comparative study.

Hallux Interphalangeal Arthrodesis Following First Metatarsophalangeal Arthrodesis

Category: Midfoot/Forefoot Introduction/Purpose: Hallux interphalangeal (IP) arthritis can occur after first metatarsophalangeal (MTP) arthrodesis. IP Arthrodesis is a standard treatment, but in the setting of prior MTP surgery there will be increased stress on the IP joint and decrease local blood supply. These may result in diminished potential for bone healing. This investigation seeks to assess the outcomes of hallux IP arthrodesis after first MTP arthrodesis. Methods: Charts were retrospectively reviewed for patients who underwent interphalangeal arthrodesis between 1/1/2007 and 4/3/2017 and who had a minimum of 12-weeks of follow-up. We compared patients with and without prior ipsilateral first MTP arthrodesis. Charts were reviewed for clinical and radiographic union. Outcomes of interest were nonunion, complications, time to union and speed of union. Statistical data were analyzed by multivariable regression. Results: There were 42 patients whose median follow-up was nine (range, 3-135) months. Median time from previous first MTP arthrodesis until IP arthrodesis was 54 months. Six nonunions (35.3%) occurred in 17 patients with prior first MTP arthrodesis. Only two nonunions (8.0%) occurred in 25 patients with isolated IP arthrodesis. The multivariable risk difference of nonunion was 53.3% (P = .001). Prior first MTP arthrodesis also was more likely to have complications (52.9% vs. 24.0%, respectively). The multivariable risk difference of complications was 35.7% (P = .082). The speed of bone healing was statistically significant, with a multivariable rate ratio of 0.21 (P = .012). Conclusion: Prior first MTP arthrodesis resulted in 4.8 times slower bone healing for IP arthrodesis. The numbers needed to harm was two patients for nonunion and three patients for any complication.

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.