An MRI-Based Patient-Specific Computational Framework for the Calculation of Range of Motion of Total Hip Replacements

Abstract

The calculation of range of motion (ROM) is a key factor during preoperative planning of total hip replacements (THR), to reduce the risk of impingement and dislocation of the artificial hip joint. To support the preoperative assessment of THR, a magnetic resonance imaging (MRI)-based computational framework was generated; this enabled the estimation of patient-specific ROM and type of impingement (bone-to-bone, implant-to-bone, and implant-to-implant) postoperatively, using a three-dimensional computer-aided design (CAD) to visualize typical clinical joint movements. Hence, patient-specific CAD models from 19 patients were generated from MRI scans and a conventional total hip system (Bicontact® hip stem and Plasmacup® SC acetabular cup with a ceramic-on-ceramic bearing) was implanted virtually. As a verification of the framework, the ROM was compared between preoperatively planned and the postoperatively reconstructed situations; this was derived based on postoperative radiographs (n = 6 patients) during different clinically relevant movements. The data analysis revealed there was no significant difference between preoperatively planned and postoperatively reconstructed ROM (∆ROM) of maximum flexion (∆ROM = 0°, p = 0.854) and internal rotation (∆ROM = 1.8°, p = 0.917). Contrarily, minor differences were observed for the ROM during maximum external rotation (∆ROM = 9°, p = 0.046). Impingement, of all three types, was in good agreement with the preoperatively planned and postoperatively reconstructed scenarios during all movements. The calculated ROM reached physiological levels during flexion and internal rotation movement; however, it exceeded physiological levels during external rotation. Patients, where implant-to-implant impingement was detected, reached higher ROMs than patients with bone-to-bone impingement. The proposed framework provides the capability to predict postoperative ROM of THRs.

Do hip resurfacing and short hip stem arthroplasties differ from conventional hip stem replacement regarding impingement‐free range of motion?

“…Firstly, we derived preoperative bone geometries using segmentation and reconstruction techniques based on the coordinate systems according to our previous studies. 8,27 Secondly, we virtually implanted the three implant designs resembling two situations for each patient: a preoperatively planned situation based on preoperative MRI scans as well as radiographs and a preoperatively reconstructed situation based on postoperative radiographs. Each virtual implantation was conducted under the supervision of an experienced surgeon and according to the surgical manual of the implant manufacturer.…”

“…Virtual implantation was conducted for the conventional hip stem as previously described for preoperatively planned and postoperatively reconstructed situation. 27 Briefly, resection was performed as prescribed in the surgical manual resembling the principle of hip step osteotomy and an osteotomy plane angle of 55°r elative to the femoral shaft axis. The hip stem was aligned parallel to the femoral shaft and aimed to be well-centered in the medullary femoral canal.…”

“…The stem was implanted virtually analogous to the procedure for the preoperatively planned situation, using the postoperative radiographs to derive the implant orientation with regard to our previous study. 27 Orientation of the acetabular cup was derived according to Murray et al 33 and Liaw et al 34 The bone resection necessary for virtually implanting the short hip stem in case of the preoperatively planned situation was performed as prescribed in the surgical manual and according to preoperative planning. Virtual bone resections were performed with an osteotomy plane taken from preoperative planning.…”

“…All analyses of the statistical significance were performed using GraphPad Prism 9.2 (GraphPad Software, La Jolla, CA, USA), and a p ≤ 0.05 was considered as statistically significant. First, the t test for connected samples was used to test whether statistically significant differences exist between preoperatively planned situation and postoperatively reconstructed situation for patients who received conventional hip stem (n = 6), patients who received short hip stem (n = 8), and patients who were F I G U R E 2 Workflow of the previously described CAD method 27 based on patient data, e.g. magnetic resonance imaging (MRI) scan, adapted to evaluate the influence of the three different design principles conventional hip stem, short hip stem, and hip resurfacing arthroplasty (HRA) on the resulting range of motion (ROM).…”

Adopted walking condition for computational simulation approach on bearing of hip joint prosthesis: review over the past 30 years

“…In performing various bearing couple studies on medical implant, four approaches can be used, namely clinical study [ 16 ], experimental testing [ 17 ], mathematical formula [ 18 ], and computational simulation [ 19 ]. In the first approach, the method used are radiographic [ 20 ], computed tomography [ 21 ], and hip analysis suite [ 22 ].…”