Prospective Study
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Mar 18, 2024; 15(3): 257-265
Published online Mar 18, 2024. doi: 10.5312/wjo.v15.i3.257
Mid-term survival of the Optimys short stem: A prospective case series of 500 patients
Bryan Hamans, Sheryl de Waard, Sjoerd Kaarsemaker, Esther R C Janssen, Inger N Sierevelt, Gino M M J Kerkhoffs, Daniël Haverkamp
Bryan Hamans, Department of Orthopaedic Surgery, Xpert Clinic, Amsterdam 1101EA, Netherlands
Sheryl de Waard, Department of Orthopedic Surgery, Amsterdam University Medical Center, Amsterdam 1105 AZ, Netherlands
Sjoerd Kaarsemaker, Esther R C Janssen, Department of Orthopaedic Surgery, Viecuri Medisch Centrum, Venlo 5912 BL, Netherlands
Inger N Sierevelt, Centre for Orthopaedic Research, Spaarne Ziekenhuis, Hoofddorp 2134 TM, Netherlands
Gino M M J Kerkhoffs, Department of Orthopaedic Surgery and Sports Medicine, Amsterdam UMC-Location AMC, Amsterdam 1105 AZ, Netherlands
Daniël Haverkamp, Department of Orthopedic Surgery, Xpert Orthopedic Surgery Clinic, Amsterdam 1101 EA, Netherlands
Author contributions: Hamans B and Sierevelt IN analyzed the data; Hamans B, de Waard S, Kaarsemaker S, Janssen ERC, Sierevelt IN, Kerkhoffs GMMJ, and Haverkamp D prepared the manuscript; de Waard S, Kaarsemaker S, and Haverkamp D included patients; de Waard S, Kaarsemaker S, Janssen ERC, Sierevelt IN, and Haverkamp D collected data; Sierevelt IN and Haverkamp D designed the research study; All authors read and approved the final manuscript.
Institutional review board statement: This study was reviewed and approved by the Slotervaarziekenhuis en Reade Institutional Review Board (approval No. NL47055.048.13).
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: There are no conflicts of interest for any of the authors regarding this study.
Data sharing statement: Dataset is available from the corresponding author at s.dewaard21@gmail.com. Participants gave informed consent for using their data for publication.
CONSORT 2010 statement: The authors have read the CONSORT 2010 statement, and the manuscript was prepared and revised according to the CONSORT 2010 statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Sheryl de Waard, MD, Department of Orthopedic Surgery, Amsterdam University Medical Center, Meibergdreef 9, Amsterdam 1105 AZ, Netherlands. s.dewaard21@gmail.com
Received: November 1, 2023
Peer-review started: November 1, 2023
First decision: November 29, 2023
Revised: December 13, 2023
Accepted: January 16, 2024
Article in press: January 16, 2024
Published online: March 18, 2024
Abstract
BACKGROUND

In recent years, there has been an increase in the number of total hip arthroplasty procedures in the younger patient population. This active group has higher expectations of their prosthesis in comparison to the older population, and there is a greater physical demand for the prosthesis. Short femoral stems were introduced to retain proximal bone stock and joint biomechanics and became more common to implant in this specific population. Currently, the long-term survival and functional outcomes of various short stems are still being investigated in different clinics.

AIM

To determine the 5-year survival of the Optimys hip stem.

METHODS

This was a prospective multicenter cohort study of 500 patients conducted in two hospitals in the Netherlands. All patients received the Optimys short stem (Mathys Ltd, Bettlach, Switzerland). The primary outcome measure was survival of the hip stem, with revision as the endpoint. The secondary outcome measurements included patient-reported outcome measures (PROMs). Kaplan-Meier analysis was used to calculate the 5-year survival rate. Log-minus-log transformation was performed to calculate the 95% confidence interval (95%CI). Mixed model analyses were performed to assess the course of the PROMs during the 1st 2 years after surgery. Analyses were modeled separately for the 1st and 2nd years to calculate the yearly change in PROMs during both follow-up periods with accompanying 95%CIs.

RESULTS

The mean age of the total 500 patients was 62.3 years (standard deviation: 10.6) and 202 were male (40%). At a median follow-up of 5.5 years (interquartile range: 4.5-6.7), 7 patients were deceased and 6 revisions were registered, for infection (n = 3), subsidence (n = 2) and malposition (n = 1). This resulted in an overall 5-year survival of 98.8% (95%CI: 97.3-99.5). If infection was left out as reason for revision, a stem survival of 99.4% (95%CI: 98.1-99.8) was seen. Baseline questionnaires were completed by 471 patients (94%), 317 patients (63%) completed the 1-year follow-up questionnaires and 233 patients (47%) completed the 2-year follow-up. Both outcome measures significantly improved across all domains in the 1st year after the operation (P < 0.03 for all domains). In the 2nd year after surgery, no significant changes were observed in any domain in comparison to the 1-year follow-up.

CONCLUSION

The Optimys stem has a 5-year survival of 98.8%. Patient-reported outcome measures increased significantly in the 1st postoperative year with stabilization at the 2-year follow-up.

Keywords: Total hip arthroplasty, Femoral stem, Short stem, Optimys, Survival, 5-year survival, Revision, PROMs

Core Tip: The Optimys hip stem showed an excellent 5-year survival of 98.9%, and when excluding infections this was 99.4%. This is in line with the earlier results of the Roentgen Stereophotogrammetric analysis study completed by our group, and we expect it to be in line with the National Institute for Health and Care Excellence criteria on total hip arthroplasty for the 10-year follow-up. This study showed that in a large, varied patient population there is similar survival as other cohorts with short femoral stems.