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Patellar Tendon Tenodesis for the Treatment of Patella Alta
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Operative technique and
Rehabilitation
Surgery was performed in the supine position
with a tourniquet on the proximal thigh. The
procedure included a distalization of the tibial
tubercle followed by tenodesis of the patellar
tendon (fig. 2) [22]. A longitudinal incision was
created from the inferomedial patellar border
extending 6cm below the tibial tubercle,
allowing visualization of the medial and lateral
borders of the tendon and the tibial tubercle.
After creation of two 3.2mm drill holes for
fixation, the tibial tubercle was osteotomized as
a 6cm bone block approximately 8mm in
thickness. The bone block was then distalized
an average of 9mm (range 6-16mm) depending
on the degree of patellar alta that was present
with a goal of achieving a Caton-Deschamps
index of 1.0. Medialization was also performed
in 22 knees (81.5%) (mean medialization 7mm,
range: 2 to 11mm).
Prior to fixation of the bone block, two suture
anchors were placed near the top of the original
location of the tibial tubercle, approximately
3cm below the joint line (fig. 2A). The bone
block was then fixed in the distalized position
with two 4.5mm bicortical screws (fig. 2B).
The sutures from each anchor were then passed
through the tendon and tied, tenodesing the
patellar tendon into the proximal tibia (fig. 2C).
An advancement of the vastus medialis obliquus
(VMO) muscle was then performed [9, 10] and
the incision was then closed over a drain.
Weightbearing was allowed on the first
postoperative day with the use of an extension
brace. A supervised rehabilitation protocol was
initiated focusing on gradual restoration of
knee range of motion. Flexion was limited to
90 degrees for the first month following surgery,
after which unrestricted motion was allowed.
Strengthening began one month post-
operatively with a focus on the quadriceps and
VMO in particular. Biking was allowed from
two months post-operative and a return to
unrestricted activities including running was
expected 4 to 6 months following surgery.
Outcome Assessment
Clinical examination at last follow-up included
a physical examination with assessment of
patellar apprehension. Any subsequent
operations on the index knee or recurrent
patellar dislocations were documented. Knee
function was assessed with the IKDC subjective
knee evaluation [12]. Patient satisfaction with
the procedure was also assessed. Radiological
examination included assessment of patella
height by the Caton-Deschamps index and the
Insall-Salvati method. The length of the patellar
tendon was determined by measuring the
distance from the inferior tip of the patella to
the site of the patellar tendon tenodesis (metal
suture anchors) (fig. 3).
Fig. 2: Schematic drawing
of a patient with patella
alta and a long patellar
tendon (A) treated with
distalization of the tibial
tubercle (B) and patellar
tendon tenodesis (C).