The Use of a T-Plate as ‘‘Spring Plates’’ for Small
Comminuted Posterior Wall Fragments
Bruce H. Ziran, MD,* Jill E. Little, BA,† and Ramsey C. Kinney, MD, PhD*
Summary: In the treatment of posterior wall fractures of the
acetabulum, a modified distal radius T-plate can be substituted for one
third tubular spring plates for fixation of thin, small, or comminuted
posterior wall fragments. This technique is described as well as a case
series of 33 patients with various posterior wall acetabular fractures.
Key Words: acetabular fracture, posterior wall, internal fixation,
(J Orthop Trauma 2011;25:574–576)
In certain acetabular fracture patterns, the posterior wall
fragment can be very thin or quite small (less than 5 mm) and
cannot be adequately secured with an overlying 3.5-mm
reconstruction plate. In such cases, the use of a spring plate has
been advocated, which is usually made from a one third
tubular plate that is contoured to provide a compressive force
on the small fragment over which a standard 3.5-mm
reconstruction plate is applied.1,2The joint reactive force
vector across the hip is 2.35 times body weight with the
posterior wall bearing 24% of this load.3The small spring
plates serve to distribute force over the small fracture segments
and also help avoid intra-articular penetration of screws that
may have been used to secure such fragments close to the
articular surface. In the eventof greater comminution or longer
rim fragments, multiple one third tubular plates have been
used. Because the one third tubular plate has a relatively thin
profile and width, multiple plates are needed for extended
fragments or comminution.
In the present report, we propose a technical modifica-
tion whereby the contact area for a spring plate can be
increased easily andwithout havingto resort tomultiple plates.
Using a distal radial T-plate in the same manner as the spring
plate, the area of contact nearest the articular surface is
broadened. A standard overlying 3.5-mm reconstruction plate
can be used as with one third tubular plates. We report on the
technique and our small case series of 33 patients.
This technique is indicated in acetabular fractures with
a small posterior wall fragment that requires stabilization and
cannot be entirely contained with the standard 3.5-mm
reconstruction plate. The T-plate chosen can be either a standard
T-plate orangleT-plate.Theplate can besized by removalofthe
proximal end (Fig. 1). The distal ‘‘T’’ portion can be slightly
bent and the remainder of the plate gently curved to match the
contour of the posterior wall. The plate will initially be convex,
but when the fixation of the stem to the bone is performed, the
platewill naturally flatten and provide the ‘‘spring’’ effect, in the
same manner that occurs with one third tubular plates (Fig. 2).
The plates should be independently attached to the pelvis with
a screw before having an overlying reconstruction plate applied.
Additional fixation, especially in the case of extensive
comminution, can be achieved by removal of the distal portion
of the T-plate to create multiple prongs to aid in securing the
fragments (Fig. 3A).
Like any pronged spring plate, care should be taken to
ensure that the prongs are not beyond the osseous edge of the
bone into the labrum or femoral head, which would result in
abrasive wear. Other potential complications associated with
spring plates in general include overcontouring leading to
inadequate buttressing of the wall fragments as well as errors
in sizing the plate that can result in extension into the greater
sciatic notch and irritation of the rotators and sciatic nerve.
Correct placement of the reconstruction plate is also important
to avoid excessive loading of the thinner spring plate.
During the time period of 2003 to 2008, we performed
the previously described technique on 33 patients ranging
from 18 to 79 years of age who required this type of plate
because of very thin, small, or comminuted posterior wall
fragments (Table1). We did not havea control group using one
third tubular plates for comparison. All fractures had
a posterior wall element, but the overall fracture patterns
included simple posterior wall, extended posterior wall,
superior posterior wall, posterior wall with posterior column,
transverse posterior wall, and T-type with posterior wall. The
mechanisms of injury were motor vehicle crash, motorcycle
Accepted for publication August 23, 2010.
From the *Department of Orthopaedics, Atlanta Medical Center, Atlanta, GA;
and †St. Elizabeth Health Center, Youngstown, OH.
No funds were received in support of this work.
No benefits in any form have been or will be received from a commercial party
related directly or indirectly to the subject of the manuscript.
B. H. Ziran is a paid consultant for Stryker, Synthes, Medtronic and has equity
position with Tekartis.
Reprints: Bruce H. Ziran, MD, Director of Orthopaedic Trauma, Atlanta
Medical Center, Orthopaedic Residency Program, 303 Parkway Drive NE,
Atlanta, GA 30312 (e-mail: email@example.com).
Copyright ? 2011 by Lippincott Williams & Wilkins
574|www.jorthotrauma.comJ Orthop Trauma?Volume 25, Number 9, September 2011