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It has to be expected that drill holes in the
patella will act as stress raisers and might
therefore predispose to fractures. Keeping this
in mind the size and position of the hole should
be carefully considered. Holes larger than
3.5mm should probably be avoided. Transverse
drill holes through the patella will result in
more serious fractures then drill holes through
the medial rim.
Redislocations
Redislocations seems to be rare, in the
literature it varies between 0-4% [5, 7, 24]. In
our series there were only three redislocations
all three associated with a fracture of the
medial rim of the patella. In Smith’s [26]
review article there was only two post
reconstruction patella dislocations or sub
luxations in 186 knees; in five patients there
were a positive apprehension sign.
Localized tenderness
Localized tenderness in the region of the medial
epicondyle related to either the graft or the
internal fixation used can be an irritating
complication. Nomura [20] reported an
incidence of 40% as a result of using a staple
for fixation just distal to the adductor tubercle.
Christiansen [5] reported 50% tenderness over
the medial epicondyle Steiner [28] had to
remove irritating screws in 10% of his
patientsWe [10] use a deep seated bone anchor
on the medial femur and had a 6% incidence of
mild localized tenderness at the exit of the
graft; no surgical intervention was necessary
for this.
P-F degeneration
In a average 7 (4.4-9.3) year follow-up of our
first 29 patients [10] the Tegner (5.8) Lysholm
(88.5) and IKDC (81) scores were statistically
unchanged at 3,5 and 7 years follow-up. P-F
cartilage damage at the time of the MPFL
reconstruction had a negative effect on the
Lysholm score but no effect on the Tegner and
IKDC scores. In a 29 month follow-up in a
consecutive group of isolated MPFL
reconstructions in 22 of our patients [9] there
was no statistical correlation between the
Kujala score; trochlea dysplasia and Caton
Deschamps index. There was a weak
correlation between a lower score; patella
tendon length and Bernageau measurement of
patella height. There was however a statistical
significant correlation between P-F degenera
tion at the time of the reconstruction and a low
Kujala score.
It does seem that development or even
progression of P-F degeneration might be
prevented or at least stalled by an isolated
MPFL reconstruction. Nomura, in a 12 year
follow up, came to the same conclusion [20].
Fig. 5 : Tranverse patella fracture secondary to
transverse drill hole for MPFL reconstruction.