全距骨置換術（TTR）の転帰と分類
Mark B Davies1, Ciaran Nolan1, Ian T Sharpe2
1Sheffield Teaching Hospitals NHS Trust, Sheffield, UK.
Aims:
Total talus replacement (TTR) is an innovative technology with increasing availability. The aim of this study was to present the largest series to date of TTRs performed in the UK describing the outcomes, expected function, and complications.
Methods:
A total of 27 consecutive TTRs, which were undertaken between June 2019 and Decemeber 2024 in four tertiary centres, were included in the study. Prospectively collected patient-reported outcome measures (PROMs) including the Manchester-Oxford Foot Questionnaire (MOXFQ), visual analogue scale (VAS), EuroQol five-dimension questionnaire (EQ-5D) scores, and the Tegner Activity Scale (TAS), at various timepoints were recorded and compared.
Results:
Of the 27 TTRs, eight were combined with a total ankle replacement (TATTR). Of the remaining 19 TTRs, 15 were fully articulating and four were constrained by intended bone-metal incorporation at one or more joint surface. The most common indication was idiopathic or post-traumatic avascular necrosis (AVN) of the talus (18/27). At a mean follow-up of 22 months (7 to 68), the mean MOXFQ improved significantly from 80.8% (95% CI 75.1 to 86.4) preoperatively to 43.2% (95% CI 32.1 to 54.3) (p < 0.001). The mean VAS score increased significantly from 44.5 (95% CI 33.8 to 55.2) preoperatively to 76.2 (95% CI 69.7 to 82.7) (p < 0.001). The mean EQ-5D improved significantly from 10.7 (SD 2.141 preoperatively to 7.4 (SD 2.8; p < 0.001). The mean TAS increased by 1.8 (0 to 6). Three patients (11%) underwent revision, two requiring increased constraint and another for deep infection.
Conclusion:
TTR can be used for patients with destruction of the talus to relieve pain and to improve both function and activity. Patients having surgery for an elective indication appear to improve more than those whose replacement follows trauma. Constrained implants produced similar results to fully articulating implants. It is a technically difficult procedure and as the numbers which are undertaken increases, standardized terminology must be used in further prospective follow-up.
