Complications and Radiographic Outcomes After Tibiotalocalcaneal Fusion With a Retrograde Intramedullary Nail

Reaming for Tibiotalocalcaneal Nailing Removes Only 10% of the Ankle and Subtalar Joints

OBJECTIVES

Tibiotalocalcaneal (TTC) nailing in the setting of acute ankle trauma has become increasingly popular. No consensus exists as to whether formal joint preparation is necessary, although there is some concern that residual motion at unprepared joints may lead to implant loosening and/or breakage. The objective of this study was to quantify the proportion of tibiotalar and subtalar articular surface destruction that occurs during reaming for TTC nail fixation.

METHODS

Twelve cadaver lower extremities were procured. The specimens were pinned into neutral ankle and hindfoot alignment. A guidewire was inserted under fluoroscopy, followed by a 12-mm opening reamer. The specimens were then dissected, exposing the tibial plafond, talar dome, posterior facet of the talus, and posterior facet of the calcaneus. Images of each joint were obtained, and ImageJ software was used to calculate the total joint surface area and the area of articular destruction.

RESULTS

The mean proportion of articular cartilage destruction was 9.3%, 10.3%, 8.9%, and 10.3% for the tibial plafond, talar dome, posterior facets of the talus, and posterior facets of the calcaneus, respectively. No joint destruction was observed in the middle facets of the subtalar joint.

CONCLUSIONS

Reaming for TTC nail placement violates approximately 10% of each articular surface of the tibiotalar and subtalar joints. Retention of 90% of the articular surface may allow for residual motion at the joints and therefore potentially substantial stress on the implant. Formal joint preparation for the purposes of achieving fusion during TTC nail placement may be beneficial to prevent implant loosening or breakage.

Patients' point of view on the long-term results of total ankle arthroplasty, tibiotalar and tibiotalocalcaneal arthrodeses

INTRODUCTION

Total ankle arthroplasty (TAA), tibiotalar (TT) arthrodesis and tibiotalocalcaneal (TTC) arthrodesis are common surgical procedures that are sometimes concurrent. The functional results of TTC are deemed to be inferior because of the double joint sacrifice. Patient-Reported Outcome Measures (PROMs), as well as satisfaction scores, are commonly used to assess the outcome of these surgeries, but lack at capturing patients' ability to cope with potential functional limitations. The objective of our study was to compare the results of TAA, TT and TTC arthrodeses according to patients' point of view. We proposed two hypotheses: 1) TAA confer better results than TT arthrodeses, 2) and TT arthrodeses confer better results than TTC arthrodeses, on this specific criterion.

MATERIAL AND METHODS

We carried out a retrospective study integrating all TAA, TT and TTC arthrodeses performed in our center from 2010 to 2017. These surgeries were compared using PROMs (Foot Function Index (FFI), Foot and Ankle Outcome Scale (FAOS) and 12-Item Short Form Survey (SF-12)), a satisfaction rating and self-reported perceived recovery state.

RESULTS

Fifty-one patients were included in the TAA group, 50 in the TT group and 51 in the TTC group. The mean duration of follow-up was 46±20.8 months. The TAA group had better results than the TT group regarding the FFI score and satisfaction, thus confirming our primary hypothesis. On the other hand, no significant difference was found between the TT group and the TTC group, which invalidated our secondary hypothesis. No significant difference between the groups was found regarding the distribution of patients' perceived recovery state.

CONCLUSION

Our hypothesis was not confirmed. In fact, TAAs, TT and TTC arthrodeses presented substantially similar results. Although it is difficult to compare surgeries with different indications, it is surprising to find that the patients' perceived recovery state, deviating from the usual clinical and radiological results, are relatively similar.

LEVEL OF EVIDENCE

IV; Retrospective study.

The stability of total talar prosthesis-How stable to dislocation? Cadaveric study

The aim of this study was to characterize ankle stability of total talar prosthesis (TTP) and to determine the effect of implant sizes on stability as well as the resistance to TTP dislocation. Twelve below-knee cadaveric specimens were divided into two groups. Group 1 received a size matched implant and Group 2 received downsized implant by 5%. The stability assessment under fluoroscopy was performed for each cadaver in its native state. Following TTP insertion process, each then underwent evaluation of the TTP ankle stability. The stability of pre- and post-TTP was compared. (1) Anterior drawer distance. (2) Talar tilt angle under varus and valgus stress. (3) Subtalar tilt angle under varus stress was measured. Finally, the dislocation test was performed using the aforementioned testing conditions, then the stress force was slowly increased from 0 to 350 N, during which time it was observed on fluoroscopy all the time. Compared to pre TTP ankles, varus and anterior drawer stress showed significant instability (p < 0.001-0.031). Only anterior drawer stress in smaller sized implants showed significant instability when compared to identical sized implants (p = 0.008). No dislocation was seen under varus, valgus, and subtalar stress. However, anterior dislocation was observed in all cases of smaller size implant group (p = 0.045). TTP implant was stable under valgus and subtalar stress. However, clinicians should pay attention to anterior instability. Notably, downsized implants should be considered carefully to minimize the chance of anterior dislocation.

Deciding Between Ankle and Tibiotalocalcaneal Arthrodesis for Isolated Ankle Arthritis

After isolated ankle (tibiotalar) arthrodesis, the triceps progressively shifts the subtalar joint into varus thus blocking compensatory motion from the midtarsal joints. In a tibiotalocalcaneal arthrodesis, the subtalar may be fixed with the correct valgus. Comparison between ankle and tibiotalocalcaneal arthrodesis does not clearly favor one over another for pain relief, satisfaction, and gait analysis. Compensatory sagittal plane motion through the midtarsal joints when the subtalar is fixed in valgus may be responsible for these results. Tibiotalocalcaneal arthrodesis has become our procedure of choice over isolated tibiotalar for end-stage ankle arthritis regardless of the radiographic state of the subtalar.