The learning curve following adoption of a novel short-stem prosthesis in total hip arthroplasty: implications on short-term patient outcomes
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Short-stem (SS) hip prostheses for total hip arthroplasty (THA) have gained popularity as surgeons strive to reproduce physiological stress distributions at the proximal femur. Additionally, as THA indications continue to target younger populations, preservation of femoral bone stock for potential revision surgeries is particularly appealing. However, little is known regarding the short-term complications of each variety of short stem during the learning curve period. The purpose of this study is to evaluate the short-term complications among the THA recipients with the use of a novel SS hip prosthesis.
A retrospective chart review was performed of all patients undergoing primary THA utilizing an Echo Bi-Metric Microplasty hip stem. Patient demographics, surgical factors, complications and quality outcomes were collected utilizing our institution’s data warehouse and verified by chart review.
In total, 182 SSs were implanted in 168 patients undergoing primary THA. Of these, 5 (2.9%) patients sustained a periprosthetic fracture. Two fractures occurred during the index hospital admission, and 3 occurred in the post-discharge period. Subset analysis demonstrated that 4 (80%) fractures had occurred during the initial learning curve period, within the first 30 surgical cases with a SS.
Short-stem hip prostheses are a safe alternative for THA. The results of the present study demonstrate a fracture incidence of 2.9% among patients. However, surgeons should remain cautious when utilizing new implant system and expect a learning curve. In this study, 80% of periprosthetic fractures following SS THA occurred within the first 30 cases for experienced arthroplasty-trained surgeons.
KeywordsShort stem Dual taper Total hip arthroplasty Learning curve Outcomes Periprosthetic fracture
R.S., J.S., and M.S. conceived the study design. J.P., A.A., and J.F. investigated the learning curve associated with adopting a novel prosthetic design. J.P., A.A., and J.F. carried out the experiment, performed the analytic calculations and wrote the manuscript under the supervision of R.S., J.S., and M.S. All authors provided critical feedback and helped revise the final manuscript.
Compliance with ethical standards
Conflict of interest
Jorge A. Padilla MD, Afshin A. Anoushiravani MD, and James E. Feng MD declare no conflicts of interest. Ran Schwarzkopf MD is a paid consultant for Smith & Nephew and Intellijoint; owns stocks in Intellijoint and Gauss Surgical; is a board members/committee for AAOS and AAHKS. James Slover MD has received research support from Biomet and is a board member/committee of AAHKS. Scott Marwin MD is a paid consultant for Zimmer and Integer Consulting.
All procedures performed were in accordance with ethical standards. This study analyzed de-identified data and thus was exempted from human-subjects review by our Institutional Review Board (IRB).
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