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ORTHOPEDICS September 2011;34(9):464.
Stubby Stems: Good Things Come in Small Packages
by Adolph V. Lombardi, MD; Keith R. Berend, MD; Vincent Y. Ng, MD
Standard-length porous-coated tapered femoral stems perform exceedingly
well in primary total hip arthroplasty (THA) at long-term follow-up.
Nevertheless, there are multiple reasons to strongly consider the
relatively new concept of short tapered stems. First, there is already a
wide variation in the lengths of “standard” components and the ideal
length is unknown. The goal of tapered stems is to load the proximal
femur, and shortened stems accomplish this task. Second, while the
distal extension may help prevent varus, unlike cemented stems, which
are failure-prone with varus alignment, tapered designs are not.
Additionally, elimination of the distal extension may reduce potential
stress shielding. Third, short stems obviate problems with
proximal-distal mismatch, excessive femoral bowing, diaphyseal
deformities, and preexisting hardware. Fourth, implantation of smaller
components requires less violation of bone and soft tissue, facilitating
less invasive surgical approaches and favorable revision settings if
necessary. Fifth, in comparison to hip resurfacing and other
unconventional short-stem designs, tapered stems are familiar to most
orthopedic surgeons and do not incur a steep learning curve. Finally,
our early experience with this implant in 1750 THAs since 2006 has been
excellent. In a series of >650 THA, compared to standard-length tapered
stems, the short stem had equivalent clinical outcome scores,
significantly fewer femoral fractures (12/389 [3.1%] vs 1/269 [0.4%]),
and only 1 (1/269 [0.4%]) femoral revision (infection) at 2-year
follow-up. Short stems represent the logical progression of a proven
precedent in standard-length tapered stems.
Drs Lombardi and Berend are from Joint Implant Surgeons, Inc, the
Department of Orthopedics, The Ohio State University, and Mount Carmel
Health System, Dr Ng is from Department of Orthopedics, The Ohio State
University, and Dr Lombardi is also from the Department of Biomedical
Engineering, The Ohio State University, New Albany, Ohio.
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