Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_17_библиотеки_им_акад_М_И_Перельмана
.pdf
Patellar Resurfacing
https://t.me/medicina_free
inCemented Total Knee
Arthroplasty
SachinAllahabadi andDerekWard
Contents
20.1 Introduction – 222
20.2 Case Example andSurgical Technique – 222
20.3 History ofControversy – 223
20.4 Natural History ofthePatellofemoral Joint andPatterns
ofWear – 224
221
20
20.5 Indications forResurfacing or Not Resurfacing – 225
20.6 Risks ofPatellar Non-resurfacing andOutcomes ofSecondary
Resurfacing – 226
20.7 Risks ofPatellar Resurfacing – 226
20.8 Comparison Studies ofResurfacing – 227
20.8.1 Randomized Controlled Trials – 227
20.8.2 Registry Data – 227
20.8.3 Bilateral Comparisons – 227
20.9 Cost-Eectiveness – 228
20.10 Technique forCemented Patella Resurfacing – 228
20.11 Conclusion – 229
References – 230
© The Author(s), under exclusive license to Springer-Verlag GmbH, DE, part of Springer Nature 2022
E. Hansen, K.-D. Kühn (eds.), Essentials of Cemented Knee Arthroplasty,
https://doi.org/10.1007/978-3-662-63113-3_20
20
https://t.me/medicina_free
222
S. Allahabadi and D. Ward
20.1 Introduction
Patellar resurfacing in total knee arthroplasty (TKA)
continues to be an area of controversy in modern
orthopedics and is an important consideration for the
arthroplasty surgeon. Multiple studies have shown
similar outcomes for patients with and without resurfacing but with increased revision rates for unresurfaced patellae. Complications associated with patellar
resurfacing, although rare, can be devastating.
Technique is critical for successful resurfacing and
surgeons should carefully consider their chosen
method.
20.2 Case Example andSurgical Technique
The patient is a 67-year-old female presenting with knee
pain refractory to conservative management and radiographs showing medial and patellofemoral osteoarthritis with varus alignment (. Figs.20.1, 20.2, and 20.3).
A standard total knee replacement is undertaken with
postoperative radiographs shown in . Figs.20.4, 20.5,
and 20.6.
The authors’ preferred surgical technique for the
patella is as follows:
5 The patella is everted (. Fig. 20.7) and measured
using a caliper (. Fig.20.8). The starting thickness
(with assumptions made for cartilage loss and knowledge of the implant thickness options) will determine the appropriate resection depth to adequately
restore the patella thickness. Care must be taken not
to leave the patella too thin and risk fracture or too
thick and risk over-stufng the joint.
5 The resection is made freehand with the patella
everted and stabilized. A relatively short, wide, and
exible saw blade allows for good control.
5 The resected piece and remaining patella
(
. Fig. 20.9) are checked for an even resection and
appropriate thickness.
5 The patella is then measured and a trial placed. Once
adequate tracking is tested, the button is drilled. To
optimize tracking, the button may be placed in a
superomedial position without overhang. The residual lateral facet may be resected back with a rongeur
or burr. Optimally, the patella should be centrally
tracking without subluxation or impingement
throughout range of motion.
5 During cementing, the bone is thoroughly washed
and dried and cement is manually pressurized into
the lug holes (. Fig.20.10).
5 The patella is then clamped and the excess cement
removed. The cement is allowed to fully harden
before the clamp is removed (. Fig.20.11).
. Fig. 20.1 Anteroposterior radiograph of the right knee demon-
strating medial more than lateral tibiofemoral compartment degenerative changes, including subchondral sclerosis, joint space
narrowing, and osteophytosis
. Fig. 20.2 Lateral radiograph of the right knee demonstrating
joint space narrowing in patellofemoral and tibiofemoral compartments with patellar osteophytes and subchondral sclerosis
Patellar Resurfacing inCemented Total Knee Arthroplasty
https://t.me/medicina_free
. Fig. 20.3 Patellofemoral radiograph of the right knee demon-
strating patellofemoral compartment joint space narrowing and
osteophytosis
223
. Fig. 20.5 Lateral bent knee radiograph of the right knee demon-
strating a cemented cruciate-retaining total knee arthroplasty design
of appropriate size without anteroposterior overhang with a
cemented resurfaced patella
20
. Fig. 20.4 Anteroposterior radiograph of the right knee demon-
strating a cemented total knee arthroplasty of appropriate size without lateral overhang, appropriate mechanical alignment, and without
loosening
. Fig. 20.6 Patellofemoral radiograph of the right knee demon-
strating a cemented total knee arthroplasty with a resurfaced patellar
component
20.3 History ofControversy
Patellar resurfacing has been controversial since the genesis of modern TKA.In 1986, John Insall published a
series of 27 knee replacements from 1974 to 1980 where
the patella was not resurfaced (Soudry etal. 1986). The
study noted very similar outcomes for those patients
compared with 100 patients with resurfaced patellae,
224
https://t.me/medicina_free
S. Allahabadi and D. Ward
20
. Fig. 20.7 Intraoperative photo demonstrating an everted patella.
The patella must rst be everted prior to resurfacing. Full visualization is important to avoid damage to the extensor mechanism
thus questioning the need for resurfacing. This controversy has continued to the present day with rates of
resurfacing varying widely (11–76%) in registry studies.
Currently, multiple studies show similar outcomes in
cases of patellar resurfacing versus non-resurfacing;
however, the incidence of reoperation is consistently
higher in patients without resurfacing. This may be
largely due to the fact that an unresurfaced patella
allows for a surgical option for anterior knee pain after
total knee replacement, despite the fact that only half of
the patients had an improvement of symptoms after secondary resurfacing (Parvizi etal. 2012). Although the
risks of reoperation are higher for patients without
patellar resurfacing, the complications associated with
resurfacing can be devastating, particularly that of
patellar fracture with concomitant extensor mechanism
disruption.
> Given the excellent outcomes possible with and with-
out resurfacing, thoughtful consideration should be
employed when deciding the fate of the patella.
. Fig. 20.8 Intraoperative photo demonstrating measurement of
pre-resurfacing patellar thickness using calipers. Knowing the starting thickness helps guide the depth of resection as guided by the specic patellar implant design
20.4 Natural History ofthePatellofemoral
Joint andPatterns ofWear
According to the Centers for Disease Control and
Prevention, half of the people (46%) will develop painful knee arthritis in their lifetime, with varying wear patterns. Compartmental involvement of osteoarthritis
vary in population studies, however, the incidence of
isolated, radiographic tibiofemoral arthritis was as high
as 23% in the Framingham study population with a
combined patellofemoral and tibiofemoral incidence of
19.3% (the isolated patellofemoral incidence was 5.3%)
(McAlindon etal. 1996). Another study by McAlindon
et al. found that isolated medial compartment disease
occurred in 21% of men and 12% of women in a cohort
of 513 patients, while combined medial and patellofemoral disease occurred in 7% of men and 6% of women
(McAlindon et al. 1992). Based on these studies, it
appears that the patellofemoral joint may be spared in a
signicant portion of arthritic population.
Patellar Resurfacing inCemented Total Knee Arthroplasty
https://t.me/medicina_free
225
20
. Fig. 20.9 Intraoperative photo demonstrating the patellar artic-
ular surface after resection with a thin saw blade using freehand
technique. The articular cartilage has been removed with the cut
depth. After resection, thickness of the patella should be remeasured
to evaluate the symmetry of the cut and to gauge if additional resection is necessary or if too much resection was performed
20.5 Indications forResurfacing or Not
Resurfacing
There are certain populations for whom patellar resurfacing is generally indicated. Inammatory arthritis is
often reported as an indication to resurface the patella,
however, this is not universally the case for all surgeons.
Certain studies have shown that obese patients have an
increased rate of patellofemoral pain after TKA and a
higher rate of patellofemoral complications have been
reported with increased weight in unresurfaced patellae
(Wood etal. 2002; Berend etal. 2007). The ideal BMI or
weight is not known as an absolute indication for patella
resurfacing, but these factors should likely be an integral
part of surgical decision-making.
The degree of patellofemoral arthritis present is an
important component of selective resurfacing with the
greater degree of arthritis warranting resurfacing. In a
prospective, randomized study of 500 TKAs, patients
with Outerbridge grade IV arthritis had a signicantly
higher secondary resurfacing rate, whereas patients with
. Fig. 20.10 Intraoperative photo demonstrating cement applica-
tion onto the previously cut patella. The cement is manually applied
to the patellar surface and pressurized into the previously drilled lug
holes
grade I to III arthritis had a very low rate of revision
surgery (Rodríguez-Merchán and Gómez-Cardero
2010).
Given the suggestion of lower durability of resur-
faced patellae in the literature, younger patients may be
considered for patella retention (Robertsson etal. 2000).
Tracking and congruency are important issues as well
and if the unresurfaced patella does not track well
(despite appropriate component rotation) or is not congruent with the chosen prosthesis, then resurfacing
should be considered. If the patella is too thin to be
safely resurfaced the surgeon should consider retention,
although there is no clear agreement as to the specic
thickness required for resurfacing.
The literature has classically described 12mm or less
of remaining bone as a risk factor for periprosthetic
fracture, however, this has been disputed (Koh et al.
2002; Lie etal. 2005). Some authors describe the change
in thickness or amount of bony resection as a risk factor
for fracture, with one retrospective analysis with a fracture group having a change in thickness of −0.5 mm
compared to the non-fracture group of +1.05mm and
bony resection greater in the fracture group (average
226
https://t.me/medicina_free
S. Allahabadi and D. Ward
reached the same conclusions (Pakos et al. 2005; He
etal. 2011). This type of revision surgery to resurface
the patella is most often performed for anterior knee
pain, however a large percentage (approximately 10%)
of patients with resurfaced patellae have residual
anterior knee pain and secondary resurfacing has a poor
track record of alleviating such pain.
Of import is the fact that several studies have shown
patient dis-satisfaction with secondary resurfacing.
Parvizi etal. found that 20% of patients were unsatised
after secondary resurfacing for anterior knee pain
(Parvizi etal. 2012). In a series by Spencer etal., of 28
patients with 29 TKAs, 59% of patients had improved
satisfaction after secondary resurfacing, and in a series
of 27 patients reported by Munoz-Mahamud etal., only
63% reported improvement of symptoms (Spencer etal.
2010; Muñoz-Mahamud et al. 2011). A systematic
review in 2016 demonstrated of 15 included articles and
232 patients, only 148 (64%) were satised after a secondary resurfacing procedure (van Jonbergen et al.
2016).
20
. Fig. 20.11 Intraoperative photo demonstrating the nal step of
cementation—application of the patellar clamp. The clamp is used
to maintain pressure on the patellar component while the cement
hardens. Excess cement is removed along the edges of the component. Only after the cement is fully hardened should the clamp be
released
9.5 mm, 43%) compared to the non-fracture group
(average 8.1 mm, 38%) (King et al. 2015). Another
assessment of 3655 TKAs demonstrated no difference in
fractures of residual thickness <12mm or >12mm, but
there was a signicant increase in fracture risk based on
native patellar pre-resection thickness <18 mm
(Hamilton etal. 2017).
20.6 Risks ofPatellar Non-resurfacing
andOutcomes ofSecondary
Resurfacing
It well-documented that the risk of revision surgery is
higher for the patient with a non-resurfaced patella. A
meta-analysis in 2011 by Argawal etal., included 16 randomized controlled trials involving 2041 knees nding a
relative risk of reoperation for the patellofemoral articulation in resurfaced knees to be 0.52 (1.8 vs 6.2%, 95%
CI, p= 0.012) with no difference in anterior knee pain
(Agrawal et al. 2011). Several other meta-analyses
> Interpretation of increased rates of revision for unre-
surfaced patellae might be approached with caution
as non-resurfacing gives the surgeon an option for
revision of the painful TKA, thus articially increasing the rate without truly alleviating the cause of
residual pain.
20.7 Risks ofPatellar Resurfacing
Patellar resurfacing is not without downsides.
Biomechanical studies have shown a signicant increase
in retropatellar contact forces concomitant with the
decreased contact area in several different patellar
designs (Wurm et al. 2013). This increased force may
account, in part for the increased risk of patellar fracture after resurfacing and possible osteonecrosis.
> The complications associated with extensor mecha-
nism disruption in particular can be devastating.
Other complications associated with patellar resurfacing include the following:
5 Over-stufng the patellofemoral joint
5 Creating too thin of a resurfacing and subsequent
extensor mechanism weakness
5 Patellar clunk syndrome
5 Aseptic loosening
5 Malpositioning
5 Maltracking
5 Excessive tilt
5 Instability
Patellar Resurfacing inCemented Total Knee Arthroplasty
https://t.me/medicina_free
227
20
5 Osteonecrosis, and
5 Catastrophic failure of the implant
Many of these may require reoperation with unpredictable results (Burnett and Bourne 2004). Patellofemoral complications have been cited around 7–8% after
total knee arthroplasty (Dalury etal. 2013; Schiavone
Panni etal. 2014).
20.8 Comparison Studies ofResurfacing
20.8.1 Randomized Controlled Trials
Multiple randomized controlled trials exist that show
equivocal functional outcomes, a clear increased risk of
reoperation for unresurfaced patellae, but a questionable increase in anterior knee pain for those same
patients. In a meta-analysis by Argawal etal., 16 RCTs
(6925 TKAs) were analyzed for incidence of anterior
knee pain. Seven of these trials reported no difference
between the two groups, ve supported resurfacing the
patella, while one favored no resurfacing of the patella.
Overall, anterior knee pain was present in 12.9% of
cases in the resurfaced group, while 24.1% in the patellar
unresurfaced group with the RR of 0.56 (95% CI,
P<0.00001). However, when the analysis was limited to
the high-quality RCTs with random allocation and
observer blinding, there was no signicant difference
between the two groups (RR=1.03, 95% CI, P=0.90)
(Agrawal etal. 2011).
A subsequent decision-analysis paper by Helmy
et al., which argued in favor of resurfacing, used the
RR-generated looking at all studies, though not the
highest quality studies (Helmy etal. 2008). It is unclear
what the results of this decision analysis would have
been if the incidence of anterior knee pain in the parameters was set as equal. Another larger meta-analysis of
7075 knees by Pavlou etal. did not show any statistical
difference in anterior knee pain or function, but again
conrmed a higher risk of reoperation. This metaanalysis also attempted to determine if “patellarfriendly” implant designs impacted pain or function but
was unable to show a difference (Pavlou etal. 2011).
One of the largest randomized controlled trials found
slightly contradictory results in 198 TKAs in 180
patients followed for a minimum of 3years. The authors
found no signicant increase in the risk of revision but
did nd an increased incidence in the rate of anterior
knee pain in the unresurfaced group. Weight was found
to be the only predictor of anterior knee pain, however,
this was not signicant when adjusted for sex and age
(Wood etal. 2002).
An important note is that most randomized controlled trials do not include selective resurfacing, with all
degrees of patellofemoral arthritis randomized to each
treatment arm. In a recently published randomized controlled trial by Roberts etal., all patients with exposed
subchondral bone on the undersurface of the patella
were excluded and the remaining patients were randomized. In their RCT of 350 patients without signicant
preexisting patellofemoral arthritis, they found a statistically signicant, but likely clinically irrelevant improvement in patient satisfaction with an average of 7.8years
follow-up. In a subgroup of 110 patients followed for
10years, there was no difference. Importantly, there was
also no difference in revision rate (Roberts etal. 2015).
> This trial is important in demonstrating that selective
resurfacing may not only have equivalent outcomes
but may also have equivalent secondary surgery rates.
20.8.2 Registry Data
The Swedish Knee Arthroplasty Registry is an important source of data to consider regarding decisionmaking for patellar resurfacing. A review of 27,372
knees operated between 1981 and 1995 and followed
longitudinally had several interesting ndings
(Robertsson et al. 2000). In general, patients with a
resurfaced patella were more satised than patients
without resurfacing (19% versus 15% for patients with
osteoarthritis and 15% versus 12% for patients with
rheumatoid arthritis), however, the satisfaction of the
unresurfaced group was more durable over time with a
greater percentage of patients with resurfaced patellae
reporting lower satisfaction over time.
20.8.3 Bilateral Comparisons
A theoretically ideal comparison exists in patients with
bilateral total knee arthroplasty with one patella resurfaced. In the highest quality trial, Barrack etal. reported
after a randomized controlled trial with 86 patients that
they found no difference in pain and function. Thirty
(94%) of the patients were satised with the unresurfaced knee and 31 (97%) were satised with the resurfaced knee. When the patients were asked which side
they preferred, 11 (34%) said the resurfaced side, 12
(38%) said the unresurfaced side (Barrack etal. 1997).
In a series by Levitsky etal., there were 13 patients who
had bilateral mixed TKA.When asked what knee they
preferred six (46%) rated the knees as equal, six(46%)
preferred the resurfaced patella, and one (7.7%) preferred the unresurfaced patella (Levitsky etal. 1993). In
228
https://t.me/medicina_free
S. Allahabadi and D. Ward
20
a series by Enis etal., 25 patients undergoing bilateral
TKA had the right knee patellar resurfaced and the left
was unresurfaced. The resurfaced knees had superior
isokinetic measures and less patellofemoral pain and
were preferred by patients (Enis etal. 1990).
20.9 Cost-Eectiveness
Recent studies have begun to evaluate the costeffectiveness of resurfacing the patella. However, study
outcomes on costs are mixed, perhaps due to differences
in length of follow-up, cost proles, and complication
and revision rates. In the United States, Medicare reimbursements do not differ with or without patellar resurfacing, as the common CPT code for TKA (27447) does
not distinguish the decision to resurface (Meijer and
Dasa 2015). Meijer and Dasa in 2015 evaluated randomized controlled trials and concluded that the cost at
5years postoperatively was $227.92 more in Medicare
dollars for unresurfaced patellae compared to those that
were resurfaced. This cost estimate model favors more
cost-effectiveness for resurfacing as long as revision
rates after patellar resurfacing remain less than 3.54%
and revision rates after not resurfacing remain greater
than 0.77% (Meijer and Dasa 2015). In another 5-year
analysis in the United Kingdom, 1715 patients were randomized to resurfacing or not and no signicant difference existed in total healthcare costs, including those
associated with revision surgeries (Breeman etal. 2011).
An evaluation of procedure costs based in Canada
(reported in US Dollars), however, noted that not resurfacing the patella resulted in higher costs by $379.62.
This model utilized data including revisions and complications of 14 years compared to the aforementioned
studies of 5 years, though these revision rates were
derived from an Australian Registry and were assumed
to be similar in Canada (Weeks etal. 2018). Furthermore,
Zmistowski et al. evaluated prospective randomized
studies and found that resurfacing patella without signicant patellofemoral arthritis was not cost- effective,
perhaps suggesting that selective resurfacing may ultimately be a way to optimize costs (Zmistowski et al.
2019).
20.10 Technique forCemented Patella
Resurfacing
When resurfacing the patella, several factors should be
considered. The amount of resection should be adequate to minimize over-stufng of the joint (which may
impact exion and extensor mechanism mechanics)
after patellar implant placement, but should not be so
extensive to leave minimal bone stock (Bengs and Scott
2006). Optimally, the angle of resection of the patella is
parallel to the anterior femoral cut to minimize patellar
tilt.
Patellar resurfacing may be performed through freehand technique or with the assistance of cutting guides.
Exposure of the articular surface of the patella is necessary and synovial tissue around the patellar should be
excised circumferentially to allow for full visualization
and evaluation of the patellar and quadriceps insertions
(Lombardi etal. 1998).
First, patellar thickness should be assessed utilizing
calipers. It is important to evaluate the thickness
throughout the patella, as varying thicknesses are not
uncommon particularly with patellofemoral arthritis
associated with patellar subluxation.
> When evaluating patellar thickness, care should be
taken to avoid rotation of the patella, as the patella
has a median ridge that is off-center and resection
may be excessive laterally and insufcient medially
(Anglin etal. 2009).
Asymmetric resurfacing is associated with worse outcomes including patellar component loosening, patellofemoral pain, and revision surgery (Pagnano and
Trousdale 2000). Preoperative knowledge of the surgeon’s preferred system patellar component sizes is
critical to understand the amount of resection required.
> When performing the resection, disruption of the
extensor mechanism proximally and distally should
be avoided at all costs.
If using freehand technique, the surgeon may use a nonoffset oscillating sawblade with an aim to cut symmetrically across the articular surface of the patella for the
desired thickness. Freehand resection has been described
utilizing both haptic feedback and four- quadrant measurements on the posterior patellar surface (Camp etal.
2015). Utilizing haptic feedback, measurements of ante-
rior to posterior patellar thickness may be taken centrally and assessment of symmetry is performed with
haptic evaluation. The four-quadrant technique involves
caliper measurements in the center of each of the four
sections of the patella, with the assessment of symmetry
based on these caliper readings (Camp etal. 2015). Surgeons may use either or a combination of these techniques. After passing the saw, remaining posterior to the
quadriceps and patellar tendon attachments, the calipers
and/or haptic feedback are again used to reevaluate
patellar thickness and symmetry. The saw may be passed
again in an iterative process until the optimal thickness
and symmetry are created.
Patellar Resurfacing inCemented Total Knee Arthroplasty
https://t.me/medicina_free
229
20
Similar concepts are applied to the use of cutting
guides; however, after measurement of the patella with
calipers, the guide allows for setting the goal depth of
resection. After utilizing the oscillating saw through the
guide, the surgeon should still reassess patellar thickness
and symmetry, and reapply the guide or utilize freehand
technique for additional cutting if desired.
After appropriate resection is achieved, a patellar
clamp is used to place the patellar drill button guide on
the patella. Care should be taken to medialize the patellar component and to secure the clamp to avoid shifting
during drilling. Medialization of the patellar component assists with lateral movement of the extensor mechanism, which will theoretically improve tracking with a
reduced Q-angle (Camp etal. 2013; Dennis etal. 2011;
Anglin et al. 2010). The associated drill is used in the
guide lug holes to drill and a trial component may be
placed. The component selected should maximize bone
coverage, which is often limited by the proximal and distal axis of the patella which tends to be smaller than the
medial to lateral width (Dennis etal. 2011).
Residual parapatellar osteophytes should be removed
if not already done. Once the patellar trial is in place in
addition to the femoral and tibial trials, the knee is taken
through a range of motion in exion and extension and
the tracking of the patella is carefully evaluated for lateral subluxation or tilt. If maltracking of the patella is
noted, bone cuts and component rotation should be
reassessed and if these are found to be appropriate, softtissue balancing may be needed, which may include lateral retinacular release. It is also important to check
patellar component position or resection symmetry as
this can also affect tracking. The thickness of the patellar trial component plus patellar bone should be measured and be similar to that of the bony thickness prior
to resection accounting for cartilage loss (Lombardi
etal. 1998; Marmor 1988; Hurson etal. 2010).
> Cement works best via interdigitation in cancellous
spaces.
Therefore, in areas of sclerotic bone, the surgeon should
consider placing small holes with either a thin drill or
k-wire in areas of sclerosis to expose the healthy cancellous bone and allow increased area for cement to settle.
When drilling sclerotic surfaces, avoid over drilling to
the anterior cortex of the patella to reduce stress- risers
that may theoretically increase the risk of fracture. The
patella should be irrigated thoroughly and dried prior to
cementation.
When it is time to cement and implant the patellar
component, the cement is prepared through standard
technique. The cement is placed with a spatula and clean
gloves onto the posterior, resurfaced aspect of the patella.
> Using his or her ngers, the surgeon pressurizes
cement into the previously established drill lug holes
for the patellar pegs. The patellar component is
pressed into its position and the clamp is applied and
held throughout the duration of cement hardening.
Excess cement that extrudes beyond the edges of the
patellar component should be promptly removed. Once
the cement has dried, the clamp may be removed. At this
time, patellar tracking should be revisited, and the knee
should be taken through a range of motion with the
nal components in place.
Various studies have been done evaluating outcomes
with the differing patellar resection techniques. A randomized trial performed by Yuan etal. demonstrated no
signicant differences in anterior knee pain between
freehand technique or cutting guide technique groups,
in addition to no differences in functional measures,
patient-reported outcomes, or clinical examination
results postoperatively (Yuan etal. 2019). The major difference noted in the study between the freehand and cutting guide technique groups for patellar resection was
that the freehand group had signicantly more outliers
with lateral patellar tilt >10°, though the average tilt did
not vary between groups (Yuan etal. 2019). This suggests perhaps improved reliability in measure with a cutting guide. Camp et al. performed a prospective trial
comparing freehand technique with haptic feedback,
freehand technique as evaluated with four-quadrant
measurements, and cutting guide techniques (Camp
etal. 2015). In this study, freehand techniques were more
reliable with less asymmetry and less deviation from
goal thickness compared to cutting guide, although
accuracy of measurements was assessed with a quadrant
method similar to one of the freehand techniques (Camp
etal. 2015).
> It is important that when using a cutting guide to
ensure proper application in terms of security and
depth and when utilizing the saw within the guide, it is
important to be parallel to the slot.
20.11 Conclusion
Patellar resurfacing is an important consideration of total
knee arthroplasty that remains controversial. Excellent
outcomes are achievable with and without resurfacing,
and selective resurfacing is a reasonable option. The
arthroplasty surgeon should carefully weigh the risks and
benets of resurfacing specic to each patient in order to
provide the most-durable TKA with the lowest risk of
complication. Specic attention should be paid to resurfacing techniques to minimize complications.
230
https://t.me/medicina_free
S. Allahabadi and D. Ward
20
Take-Home Messages
5 Patellar resurfacing is controversial, and excellent
outcomes have been shown with or without resurfacing.
5 Complications of resurfacing can be devastating,
including extensor mechanism disruption or patellar fracture.
5 Selective resurfacing may be considered, but
regardless of surgeon preference, understanding
patient-specic risks with and without resurfacing
may impact outcomes.
5 Various techniques for patellar resurfacing exist,
including freehand techniques and use of cutting
guides.
5 It is critical to understand the surgeon’s selected
implant design and accurately measure the preresection thickness to determine the appropriate
depth of resection.
5 To achieve symmetry of the patellar cut, remea-
surement and recutting may be necessary.
5 Placement of the trial patellar component should
be done to evaluate patellar alignment and tracking prior to implantation of the nal component.
5 The cement may be placed on the articular side of
the resurfaced patella with a spatula or freehand
and should be manually pressurized into the lug
holes with constant pressure being applied with a
patellar clamp until the cement has fully hardened.
References
Agrawal M, Jain V, Yadav VP, Bhardwaj V (2011) Patellar resurfac-
ing in total knee arthroplasty. J Clin Orthop Trauma 2:77–81.
https://doi.org/10.1016/S0976- 5662(11)60048- 9
Anglin C, Fu C, Hodgson AJ etal (2009) Finding and dening the
ideal patellar resection plane in total knee arthroplasty. J
Biomech 42:2307–2312. https://doi.org/10.1016/j.jbio-
mech.2009.06.021
Anglin C, Brimacombe JM, Wilson DR etal (2010) Biomechanical
consequences of patellar component medialization in total knee
arthroplasty. J Arthroplast 25:793–802. https://doi.org/10.1016/j.
arth.2009.04.023
Barrack RL, Wolfe MW, Waldman DA etal (1997) Resurfacing of
the patella in total knee arthroplasty. A prospective, randomized, double-blind study. J Bone Joint Surg Am 79:1121–1131.
https://doi.org/10.2106/00004623- 199708000- 00002
Bengs BC, Scott RD (2006) The effect of patellar thickness on intra-
operative knee exion and patellar tracking in total knee arthroplasty. J Arthroplast 21:650–655. https://doi.org/10.1016/j.
arth.2005.07.020
Berend KR, Lombardi AV, Adams JB (2007) Obesity, young age,
patellofemoral disease, and anterior knee pain: identifying the
unicondylar arthroplasty patient in the United States.
Orthopedics 30:19–23
Breeman S, Campbell M, Dakin H etal (2011) Patellar resurfacing in
total knee replacement: ve-year clinical and economic results of
a large randomized controlled trial. J Bone Joint Surg Am
93:1473–1481. https://doi.org/10.2106/JBJS.J.00725
Burnett RS, Bourne RB (2004) Indications for patellar resurfacing in
total knee arthroplasty. Instr Course Lect 53:167–186
Camp CL, Bryan AJ, Walker JA, Trousdale RT (2013) Surgical tech-
nique for symmetric patellar resurfacing during total knee
arthroplasty. J Knee Surg 26:281–284. https://doi.
org/10.1055/s- 0032- 1330056
Camp CL, Martin JR, Krych AJ etal (2015) Resection technique
does affect resection symmetry and thickness of the patella dur-
ing Total knee arthroplasty: a prospective randomized trial. J
Arthroplast 30:2110–2115. https://doi.org/10.1016/j.
arth.2015.05.038
Dalury DF, Pomeroy DL, Gorab RS, Adams MJ (2013) Why are
total knee arthroplasties being revised? J Arthroplast 28:120–
121. https://doi.org/10.1016/j.arth.2013.04.051
Dennis DA, Kim RH, Johnson DR et al (2011) The John Insall
Award: control-matched evaluation of painful patellar Crepitus
after total knee arthroplasty. Clin Orthop Relat Res 469:10–17.
https://doi.org/10.1007/s11999- 010- 1485- 3
Enis JE, Gardner R, Robledo MA etal (1990) Comparison of patel-
lar resurfacing versus nonresurfacing in bilateral total knee
arthroplasty. Clin Orthop Relat Res:38–42
Hamilton WG, Ammeen DJ, Parks NL etal (2017) Patellar cut and
composite thickness: the inuence on postoperative motion and
complications in total knee arthroplasty. J Arthroplast 32:1803–
https://doi.org/10.1016/j.arth.2016.12.033
1807.
He J-Y, Jiang L-S, Dai L-Y (2011) Is patellar resurfacing superior
than nonresurfacing in total knee arthroplasty? A meta-analysis
of randomized trials. Knee 18:137–144. https://doi.org/10.1016/j.
knee.2010.04.004
Helmy N, Anglin C, Greidanus NV, Masri BA (2008) To resurface or
not to resurface the patella in total knee arthroplasty. Clin
Orthop Relat Res 466:2775–2783. https://doi.org/10.1007/
s11999- 008- 0420- 3
Hurson C, Kashir A, Flavin R, Kelly I (2010) Routine patellar resur-
facing using an inset patellar technique. Int Orthop 34:955–958.
https://doi.org/10.1007/s00264- 009- 0831- 0
King AH, Engasser WM, Sousa PL etal (2015) Patellar fracture fol-
lowing patellofemoral arthroplasty. J Arthroplast 30:1203–1206.
https://doi.org/10.1016/j.arth.2015.02.007
Koh JSB, Yeo SJ, Lee BPH etal (2002) Inuence of patellar thick-
ness on results of total knee arthroplasty: does a residual bony
patellar thickness of <or=12mm lead to poorer clinical outcome
and increased complication rates? J Arthroplast 17:56–61.
https://doi.org/10.1054/arth.2002.29320
Levitsky KA, Harris WJ, McManus J, Scott RD (1993) Total knee
arthroplasty without patellar resurfacing. Clinical outcomes
and long-term follow-up evaluation. Clin Orthop Relat
Res:116–121
Lie DTT, Gloria N, Amis AA etal (2005) Patellar resection during
total knee arthroplasty: effect on bone strain and fracture risk.
Knee Surg Sports Traumatol Arthrosc 13:203–208. https://doi.
org/10.1007/s00167- 004- 0508- 6
Lombardi AV, Mallory TH, Maitino PD etal (1998) Freehand resec-
tion of the patella in total knee arthroplasty referencing the
attachments of the quadriceps tendon and patellar tendon. J
Arthroplast 13:788–792. https://doi.org/10.1016/s0883-
5403(98)90032- 8
Marmor L (1988) Technique for patellar resurfacing in total knee
arthroplasty. Clin Orthop Relat Res:166–167
McAlindon TE, Snow S, Cooper C, Dieppe PA (1992) Radiographic
patterns of osteoarthritis of the knee joint in the community: the
importance of the patellofemoral joint. Ann Rheum Dis 51:844–
849. https://doi.org/10.1136/ard.51.7.844
McAlindon T, Zhang Y, Hannan M etal (1996) Are risk factors for
patellofemoral and tibiofemoral knee osteoarthritis different? J
Rheumatol 23:332–337
Соседние файлы в папке Библиотека им академика М.И. Перельмана