Revista de Medicina Desportiva (English) November 2018 | Page 30
to perform the exercises and to keep
physical activity, particularly if there
is ligament laxity. 2
When the conservative treatment
fails, surgery must be discussed, and
it is dependent on the level of func-
tional impairment. The aim of the
surgery is getting a perfect patellar
tracking with the restoration of the
anatomy and correction of the pre-
disposing factors, like the rotation
of a limb or axial mal-alignment.
Several surgical techniques have
been described.
In children with open physis and
patellar mal-tracking and predispos-
ing factors it must be considered
the reconstruction of the medial
femoropatelar ligament (MFPL), the
release of lateral retinaculum and
the correction of the rotational and
axial axes of the limb, for example,
performing a temporary hemi-
epiphisiodesis. 2 However, cadaveric
studies have shown that the release
of the lateral retinaculum increases
patellar instability. 14
The medial, distal and anterior
re-positioning of the tibial tuberosity
is non-advised procedure in grow-
ing children (boys until 16 years and
girls until 14 years of age) due to the
risk of partial blockage of growing
with subsequent genu recurvatum.
The alignment of the distal patel-
lar ligament (Roux-Goldthwait) is a
viable option for children. 2
The reconstruction of the MFPL
has become one of the surgical
techniques most important for the
chronic patellar instability. This
ligament runs from the medial
femoral epicondyle to the superior-
medial border of the patella bone.
There are descriptions of technical
for reconstruction of the MFPL with
hamstrings, with differences related
to the opening or closure of the
physis. The several surgical technics
vary according to the insertion point
at the femur and in patients with
open physis it is located 5mm below
to the distal physis of the femur.
This position prevents the proximal
migration of the graft during the
longitudinal grow of the bone. 11,15,16
A study published by Fabricant et
al confirmed the hypothesis of the
MFPL reconstruction being associ-
ated to a better high of the patella
in cases of patellar instability,
indicating that MFPL reconstruction
28 november 2018 www.revdesportiva.pt
can be useful to restore especially
the dynamic stability, but also the
static stability, placing the patel-
lar bone more medial and distal
in the trochlear groove. After the
MFPL reconstruction the patella
can’t move superior and laterally in
the trochlea, and the slightly more
distal orientation of the graft at the
point of femur insertion the high of
the patella bone decreases, which
also causes the medialization of the
patella even without other realign-
ment procedures. 11
The MFPL reconstruction allows
the correction of the patella alta in
the absence of the distalization
of the tibial tubercle, which can
avoid additional unneeded surgi-
cal procedures. What remains
uncertain is if pre-surgical patella
alta predisposes the initial injury or
if it came out from the traumatic
femoropatelar instability and from
the subsequent rupture of the MFPL.
The MFPL reconstruction in children
with hamstrings has consistently
being associated with a radiographic
decrease of the patella high which
can, subsequently, restore the bone
congruence, drawing a patellar
sulcus on the trochlear groove on
bigger angle of flexion, that would
eliminate the need of procedures to
make a concomitant digitalization. 11
The former recurrent dislocations of
the patella during infanthood leads
to changes on the cartilage signal on
the MRI on the young adults 17 , and
a study showed a better chondral
status on the arthroscopy, on aver-
age, one year after reconstruction of
the MFPL. 7
That been said, in children and
adolescents with open physis, the
osteotomies to correct the near-
articular bone deformities and
trochlear dysplasia must be delayed
and the procedures should be done
in the soft tissues. It is mandatory
to reconsider the definitive proce-
dures on a second look after growth
closure. 2
Conclusion
It is fundamental the evaluation
of the risk factors associated to
instability because the analysis
of the anatomic and radiographic
risk factors allows the choice of
an individualized treatment. The
conservative treatment is the pre-
ferred strategy of first choice, but
in cases of concomitant anatomic
predisposition and recurrence, the
reconstruction can be considered.
In these cases, when there is bone
immaturity, the reconstruction of
the medial femoropatelar ligament
can be enough, associated or not to
procedures in the soft tissue, with
the aim to have a permanent sta-
bilization of the patella, or, at least,
to gain time to perform a definitive
none procedure.
The authors deny any conflict of interests.
Correspondence:
Catarina Neto Pereira, Serviço de Ortopedia,
Hospital Professor Doutor Fernando Fon-
seca, [email protected]
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11. Fabricant P. D., Ladenhauf H. N., Salvati