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Introduction
High tibial osteotomy (HTO) is an accepted
and reliable option for the treatment of varus
osteoarthritis in young, active adults. While
HTO typically results in pain relief and
improved knee function in 80-90% of patients
[1-3], the progression of osteoarthritis often
leads to deterioration in the surgical outcome
with the passage of time [4-8]. When
symptomatic progression occurs, total knee
arthroplasty (TKA) is frequently performed. In
the 10-year follow-up study reported by Insall
et al.
, TKA was necessary in 23% of patients
previously treated with HTO [9].
The two most commonly performed HTO
techniques for varus osteoarthritis are medial
opening-wedge osteotomy (OWO) and lateral
closing-wedge osteotomy (CWO). Closing-
wedge HTO has a long history of use in patients
with varus osteoarthritis. OWO has gained
popularity in recent years because there is no
need to osteotomize the fibula and the resulting
corrections are considered to be more precise.
Significantly fewer data are available regarding
the results of opening-wedge HTO, but several
authors have reported disadvantages such as
donor-site morbidity, lower osteocyte viability
(longer time to heal), viral disease transmission,
and a more expensive fixation technique.
Moreover, weight-bearing is usually allowed
later than in CWO. For deformities greater than
10° to 15°, lateral hinge rupture and loss of
correction can occur [10]. Other disadvantages
are slight tibial lengthening and a low patella.
The latter problem is relatively common as
demonstrated by biomechanical and clinical
studies [11-13].
Although many studies have evaluated HTO,
the outcomes of the two types of HTO (OWO
and CWO) are unclear. The aim of this study
was to retrospectively analyze the results of
141 TKAs performed after HTO and compare
the TKA results between CWO and OWO.
Materials and Methods
Patients
The prospectively collected TKA registry at
our institution was queried to identify TKAs
performed after HTO. In total, 2849 TKAs
were performed at our institution from 1
January 1996 to 31 January 2012. Of these
cases, 141 arthroplasties in 118 patients were
performed in patients who had undergone prior
HTO for varus osteoarthritis (24 medial
opening-wedge and 117 lateral closing-wedge).
These 141 cases formed the study group.
High Tibial Osteotomy
Survivorship: Opening- versus
Closing-wedge
R. Bastos-Filho, P. Neyret