Pontificia Universidad Catolica de Chile, Santiago, Chile.
Hospital for Special Surgery, New York, NY, USA.
Foot Ankle Int. 2024 Aug;45(8):916-920. doi: 10.1177/10711007241251817. Epub 2024 May 17.
Isolated subtalar and talonavicular joint arthrodeses have been associated with adjacent joint arthritis and altered hindfoot kinematics during simplified loading scenarios. However, the effect on kinematics during dynamic activity is unknown. This study assessed changes in subtalar and talonavicular kinematics after isolated talonavicular (TN) and subtalar (ST) arthrodesis, respectively, during stance simulations.
Fourteen midtibia specimens received either a TN or ST arthrodesis, with 7 randomized to each group. A 6-degree-of-freedom robot sequentially simulated the stance phase for the intact and arthrodesis conditions. Bootstrapped bias-corrected 95% CIs of the talonavicular and subtalar joint kinematics were calculated and compared between conditions.
The TN decreased subtalar inversion, adduction, and plantarflexion in late stance ( < .05). The subtalar range of motion in the sagittal and coronal planes decreased by 40% ( = .009) and 46% ( = .002), respectively. No significant changes in talonavicular joint kinematics were observed after isolated subtalar arthrodesis; however, the range of motion was reduced by 61% ( = .007) and 50% ( = .003) in the coronal and axial planes, respectively.
In this model for arthrodesis, changes in subtalar kinematics and motion restriction were observed after isolated talonavicular arthrodesis, and motion restriction was observed after isolated subtalar arthrodesis. Surprisingly, talonavicular kinematics did not appear to change after isolated subtalar arthrodesis.
Both joint fusions substantially decrease the motion of the reciprocal adjacent joint. Surgeons should be aware that the collateral costs with talonavicular fusion appear higher, and it has a significant effect on subtalar kinematics during the toe-off phase of gait.
孤立的距下关节和跟舟关节融合术与简化负荷情况下相邻关节关节炎和后足运动学改变有关。然而，其在动态活动期间对运动学的影响尚不清楚。本研究评估了分别行跟舟关节（TN）和距下关节（ST）融合术后，在站立模拟期间距下和跟舟关节运动学的变化。
14 个中胫骨标本分别接受 TN 或 ST 融合术，每组 7 个随机分组。六自由度机器人依次模拟完整和融合条件下的站立相。计算并比较了距下和跟舟关节运动学的 bootstrapped bias-corrected 95% CIs。
TN 在晚期站立时减少了距下关节内翻、内收和跖屈（ < .05）。距下关节矢状面和冠状面运动范围分别减少了 40%（ = .009）和 46%（ = .002）。孤立的距下关节融合术后，跟舟关节运动学无明显变化；然而，冠状面和轴向运动范围分别减少了 61%（ = .007）和 50%（ = .003）。
在该融合模型中，孤立的跟舟关节融合术后观察到距下关节运动学改变和运动受限，孤立的距下关节融合术后观察到运动受限。令人惊讶的是，孤立的距下关节融合术后跟舟关节运动学似乎没有改变。
两个关节融合术都大大减少了相邻关节的运动。外科医生应该意识到，跟舟关节融合的附带代价更高，并且对步态的离地阶段距下关节运动学有重大影响。
