Total Ankle Arthroplasty Radiographic Alignment Comparison Between Patient-Specific Instrumentation and Standard Instrumentation

Abstract

Background Several benefits are published supporting patient-specific instrumentation (PSI) in total ankle arthroplasty (TAA). This study seeks to determine if TAA with PSI yields different radiographic outcomes vs standard instrumentation (SI). Methods: Sixty-seven primary TAA patients having surgery using PSI or SI between 2013 and 2015 were retrospectively reviewed using weightbearing radiographs at 6-12 weeks postsurgery. Radiographic parameters analyzed were the medial distal tibia angle (MDTA), talar-tilt angle (TTA), anatomic sagittal distal tibia angle (aSDTA), lateral talar station (LTS), and talar component inclination angle (TCI). A comparison of the 2 groups for each radiologic parameter’s distribution was performed using a nonparametric median test and Fisher exact test. Furthermore, TAAs with all radiographic measurements within acceptable limits were classified as “perfectly aligned.” The rate of “perfectly aligned” TAAs between groups was compared using a Fisher exact test with a significance of .05. Results: Of the 67 TAAs, 51 were done with PSI and 16 with SI. There were no differences between groups in MDTA ( P = .174), TTA ( P = .145), aSDTA ( P = .98), LTS ( P = .922), or TCI angle ( P = .98). When the rate of “perfectly aligned TAA” between the 2 groups were compared, there was no significant difference ( P = .35). Conclusion: No significant radiographic alignment differences were found between PSI and SI implants. This study showed that both techniques achieve reproducible TAA radiographic coronal and sagittal alignment for the tibial component when performed by experienced surgeons. The talar component’s sagittal alignment is similar whether or not PSI was used but is noticeably different from normal anatomic alignment by design. Level of Evidence: Level III, retrospective cohort study using prospectively collected data.

Patient Specific Instruments and Patient Individual Implants—A Narrative Review

“…The studies were each conducted with experienced surgeons. To what extent an influence exists with inexperienced surgeons could not be shown here [ 71 , 72 , 73 , 74 , 75 ].…”

Patient-Specific Instrumentation vs Standard Referencing in Total Ankle Arthroplasty: A Comparison of the Radiologic Outcome

“…19 The advantages of using PSI have been evaluated in several studies so far. 2,6,9,11,13,19 Two studies 6,13 investigated the accuracy of the final alignment when using PSI, without comparing to SR. Two further studies 11,19 presented a comparison with SR. Both studies concluded a similar accuracy between the techniques, although in the study of Hamid et al 11 the alignment was worse in the PSI group.…”

“…Some aspects considered include the higher accuracy of especially tibial implant positioning in PSI over SR and shorter operative times, which coincide with a reduced risk for wound healing disorders in PSI. 2 , 6 , 9 , 11 , 13 , 18 , 19 Disadvantages of PSI include the higher costs, the need for extensile periosteum stripping during surgery, and the need for a preoperative computed tomographic scan. 11 …”

“…Some aspects considered include the higher accuracy of especially tibial implant positioning in PSI over SR and shorter operative times, which coincide with a reduced risk for wound healing disorders in PSI. 2,6,9,11,13,18,19 Disadvantages of PSI include the higher costs, the need for extensile periosteum stripping during surgery, and the need for a preoperative computed tomographic scan. 11 The aim of this study was to compare a homogenic patient cohort treated for ankle arthritis with TAA by a senior surgeon, who was new to the use of PSI and SR for this specific implant in regard to the accuracy of both tibial and talar implant positioning, the presence of radiolucent lines on postoperative radiographs to determine the rate of delayed osteointegration/radiolucent lines, and operative times and wound healing problems.…”

Accuracy of Weightbearing CT Scans for Patient-Specific Instrumentation in Total Ankle Arthroplasty

“…Furthermore, postoperative radiographic alignment of TAA implants has not been found to be superior when comparing standard instrumentation to PSI utilizing NWBCT scans. 4 To our knowledge, there are currently no published reports defining the role of WBCT scans for preoperative TAA templating and PSI. The purpose of this study was to retrospectively assess accuracy and reproducibility of WBCT scans in determining implant position with preoperative patient-specific guides for TAA.…”