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5-7, 10-12]. Trochleoplasty procedures are
often performed with different techniques and,
most important, with various rehabilitation
protocols, which make the comparison of their
results challenging. Last, evaluating the
efficacy of trochleoplasty as a single procedure
is very difficult to do in a patient population
that usually presents with other concomitant
anomalies that also need correction, and
especially since trochleoplasty is almost always
performed in combination with soft-tissue
procedures, such as MPFL reconstruction [2, 3,
5-7, 11, 12, 14, 18, 20].
The mid-term clinical results from its
application have been also reported. Fucentese
et al.
reported the results from its application in
44 cases after an average of 4 years [6]. Kujala
score improved from 68 to 90 points (p<0.001),
and instability (p<0.001) and pain (p=0.027)
decreased significantly with no major
complications, like chondrolysis or subchondral
necrosis, except for deterioration of the
cartilage on the lateral trochlear facet. Donell
et al.
reported their data after performing
sulcus-deepening osteotomy in 17 cases after
an average of 1 year [7]. Eleven cases had
normal patellar tracking post-operatively,
Kujala score improved from a mean of 48 to 75
(p<0.05) and only 8 patients required a re-
operation (i.e. arthrolysis). Verdonk
et al.
also
reported their results in 14 cases after a mean
follow-up of 18 months [10]. In that study,
patients were assessed using the Larsen-
Lauridsen score on pain, stiffness, crepitus, and
loss of function. Seven scored poorly, three
fairly well and four well. On a subjective
scoring system 77% of patients found the
procedure satisfactory: six patients rated the
result as very good, four as good, and one as
satisfactory with only two patients rating the
result as inadequate. All these authors conclude
that sulcus-deepening trochleoplasty requires
careful attention to detail [10]. It is a technically-
demanding procedure that addresses a rare
condition with satisfactory results and
acceptable level of complications [7]. Sulcus-
deepening trochleoplasty is more suitable for
severe cases of type B and D of dysplasia,
where the presence of trochlear prominence is
amenable to correction with this technique [6].
In this study, the primary surgical treatment of
patients with recurrent patellar instability and
trochlear dysplasia included the sulcus-
deepening trochleoplasty that was also
combined with other procedures. The results of
performing additional soft-tissue or bone
surgery to trochleoplasty were satisfactory,
IKDC score improved significantly and there
was only one case of positive lateral glide test
without patellar dislocation. Other authors
report equal success rates from 90% to 100%
[5, 7, 10-12, 20].
Except for the patellar height, all radiographic
findings were significantly corrected post-
operatively, with emphasis to the lateral patellar
tilt. This can be attributed to both the trochleo
plasty and the concomitant soft-tissue procedure
(VMO plasty or MPFL reconstruction, respec
tively). Another interesting finding was the
significant decrease of the TT-TG distance,
caused by the position of the new groove in a
more lateral position. This can be helpful in
eliminating the need for an additional procedure
(medial transfer of the tuberosity), since in
cases of excessive TT-TG distance, re-
positioning the trochlea, instead of the
tuberosity, can reduce it.
Trochleoplasty procedures are a very appealing
revision option in cases of previously operated
patients with persistent patellar instability and
an undiagnosed or underestimated underlying
trochlear dysplasia [3, 5-7, 11-13, 20]. The
satisfying results that are recorded in these
patients after trochleoplasty, probably show the
need for the early recognition of a group of
patients with trochlear dysplasia in whom the
benign neglect of the dysplasia and the
application of conventional surgery for the
treatment of patella dislocation (i.e. medial
reefing, lateral release) is doomed to failure. In
the present study, patients were also classified
according to having previous surgery or not.
All patients with previous patellofemoral
surgery and persistent patellar dislocation had
associated high-grade trochlear dysplasia (type
B and D). In every case, trochleoplasty was
combined with a soft-tissue procedure.
Restoration of patellar stability, correction of
lateral tilt, functional score and patient