Patient-specific 3D-printed shelf implant for the treatment of hip dysplasia

Patient-specific 3D-printed shelf implant for the treatment of hip dysplasia: Anatomical and biomechanical outcomes in a canine model

Willemsen, Koen (University Medical Center Utrecht)
Tryfonidou, Marianna (Universiteit Utrecht)
Sakkers, Ralph (University Medical Center Utrecht)
Castelein, René M. (University Medical Center Utrecht)
Zadpoor, A.A. (TU Delft Biomaterials & Tissue Biomechanics)
Seevinck, Peter (University Medical Center Utrecht)
Weinans, Harrie (TU Delft Biomaterials & Tissue Biomechanics; University Medical Center Utrecht)
Meij, Björn (Universiteit Utrecht)
van der Wal, Bart C.H. (University Medical Center Utrecht)

2022

A solution for challenging hip dysplasia surgery could be a patient-specific 3D-printed shelf implant that is positioned extra-articular and restores the dysplastic acetabular rim to normal anatomical dimensions. The anatomical correction and biomechanical stability of this concept were tested in a canine model that, like humans, also suffers from hip dysplasia. Using 3D reconstructed computed tomography images the 3D shelf implant was designed to restore the radiological dysplastic hip parameters to healthy parameters. It was tested ex vivo on three dog cadavers (six hips) with hip dysplasia. Each hip was subjected to a biomechanical subluxation test, first without and then with the 3D shelf implant in place. Subsequently, an implant failure test was performed to test the primary implant fixation. At baseline, the dysplastic hips had an average Norberg angle of 88 ± 3° and acetabular coverage of 47 ± 2% and subluxated at an average of 83 ± 2° of femoral adduction. After adding the patient-specific shelf implants the dysplastic hips had an average Norberg angle of 122 ± 2° and acetabular coverage of 67 ± 3% and subluxated at an average of 117 ± 2° of femoral adduction. Implant failure after primary implant fixation occurred at an average of 1330 ± 320 Newton. This showed that the patient-specific shelf implants significantly improved the coverage and stability of dysplastic hips in a canine model with naturally occurring hip dysplasia. The 3D shelf is a promising concept for treating residual hip dysplasia with a straightforward technology-driven approach; however, the clinical safety needs to be further investigated in an experimental proof-of-concept animal study.

biomechanics
diagnostic imaging
hip
implant fixation
tissue engineering

http://resolver.tudelft.nl/uuid:8808987b-ab5a-4d18-ad1d-efb3ac617baf

https://doi.org/10.1002/jor.25133

0736-0266

Journal of Orthopaedic Research: a journal for musculoskeletal investigation, 40 (5), 1154-1162

Institutional Repository

journal article

© 2022 Koen Willemsen, Marianna Tryfonidou, Ralph Sakkers, René M. Castelein, A.A. Zadpoor, Peter Seevinck, Harrie Weinans, Björn Meij, Bart C.H. van der Wal