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c d
. Fig. 34.3 a–h Meticulous cementation techniques of the tibia
and the femur are important for a successful TKA.The keel a and
the tibial cut surface b are manually pressurized to assure cement
interdigitation. The entire tibial component cemented surface is
coated with cement c and impacted into place d, removing all excess
cement. The femur is then coated with cement e, similarly interdigitating the cement into the bone. The femur-cemented surface is
coated f and the component is impacted into place g, taking care to
remove all excess cement h
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ef
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B. P. Chalmers and S. B. Haas
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. Fig. 34.3 (continued)
Alternative Bearings inTotal Knee Arthroplasty
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> The entirety of the cemented surface of the tibial
implant is coated with cement prior to implantation
(.
Fig.34.3c). Recent biomechanical data has shown
that cementing early in a runnier phase rather than a
doughier phase improves initial tibial xation by
48–72% (Billi etal. 2019).
> Furthermore, cementing the keel increases initial tib-
ial xation strength by roughly 150% (Billi et al.
2019).
The real tibial component is then impacted into place fully
and the cement is methodically cleaned (. Fig.34.3d).
The femur is then exposed; a PCL retractor under the
femur can help elevate the femur for easier cementation but also places pressure on the tibial component,
ensuring that it does not lift off (. Fig.34.3e).Cement
is placed on the femur and interdigitated with the cancellous bone with nger pressurization (
. Fig. 34.3e).
The entirety of the cemented surface of the femoral
component is coated with cement (. Fig. 34.3f) and
the oxidized zirconium femoral component is impacted
into place (. Fig.34.3g). The oxidized zirconium femoral component is black, as seen in . Fig. 34.3g and
h, and has an excellent undersurface for cement bond-
ing. Cement is cleaned methodically from the knee
(. Fig.34.3h).
391
34
> We coat the implant as biomechanical data that has
shown that contamination of the implant interface by
fat reduces mean xation strength by roughly 90%
and that adding cement to the tray prior to implantation increases xation strength by 50% (Billi et al.
2019).
This technique produces reliable cement penetration
and interdigitation of both components, but especially
the tibial component, as seen in . Fig.34.4. To achieve
optimal patella cement penetration, the senior author
prepares a separate batch of cement for the patella to
assure that the cement is in the early stage (Billi etal.
2019).
34.4 Ceramic Bearings
The senior author has been utilizing oxidized zirconium,
a ceramicized metal, as a bearing surface in primary and
revision TKA for two decades with excellent results.
Oxidized zirconium implants were introduced in 1997
for knee arthroplasty as an alternative bearing surface
to cobalt–chromium (CoCr) in an attempt to reduce
polyethylene wear and improve long-term implant survival (Patel and Spector 1997).
. Fig. 34.4 Postoperative AP radiograph of a right TKA with
excellent cement mantle and penetration in the tibia
> Oxidized zirconium is a ceramicized metal, which
allows it to have the potential advantages of a ceramic
bearing surface without the fragility of ceramics (Bal
etal. 2007).
While other ceramic or ceramicized total knee implants
have been developed, most have shown overall poor
results and high failure rates compared to CoCr or oxidized zirconium implants (Song etal.
2020; Lionberger
etal. 2019).
34.5 Metal Allergy
There is continued debate on the impact of patients’
metal and nickel allergies on the incidence of
true metal hypersensitivity to total knee implants
(Saccomanno et al. 2019; Innocenti et al. 2017;
Schmidt etal. 2019; Bravo etal. 2016; Faschingbauer
etal. 2017; Hofer and Ezzet 2014).While some studies have shown that metal allergy is associated with
inferior outcomes after primary TKA, other studies have shown that metal allergy or patching test-
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B. P. Chalmers and S. B. Haas
34
ing does not affect clinical outcomes (Saccomanno
etal. 2019; Innocenti etal. 2017; Schmidt etal. 2019;
Bravo etal. 2016; Faschingbauer etal. 2017; Hofer
and Ezzet 2014).
> However, ceramicized metals, such as oxidized zirco-
nium, are an alternative bearing surface that are
“hypoallergenic” (Hofer and Ezzet 2014). As such, in
patients that are highly concerned about metal allergy
affecting their total knee outcomes, ceramicized components are an attractive option (Hofer and Ezzet
2014).
34.6 Wear Properties
A number of biomechanical studies have shown decreased
wear of oxidized zirconium compared to CoCr-bearing
surfaces (White et al. 1994; Ezzet et al. 2004, 2012;
Tsukamoto etal. 2006; Ries et al. 2002).Several invitro
studies report between 42% and 85% reduced wear of oxidized zirconium implants compared to CoCr with ultrahigh molecular weight polyethylene (UHMWPE) after
ve million or more cycles on a knee simulator (White
etal. 1994; Ezzet etal. 2004, 2012; Tsukamoto etal. 2006;
Ries etal. 2002).
Kim etal. (2010) analyzed synovial uid of 100 patients
with an oxidized zirconium implant in one TKA and a
CoCr implant in the contralateral TKA.They did not
nd any signicant difference in polyethylene particle
size or shape (Kim etal. 2010).
Furthermore, retrieval analyses have supported the
decreased invitro damage, surface roughness, and polyethylene wear of oxidized zirconium compared to CoCrbearing surfaces (Heyse et al. 2011a, b, 2014). Heyse
etal. (2011a) reported in a matched-pair retrieval analysis of 11 oxidized zirconium and 11 CoCr femoral components at a mean of 20 months of implantation that
there were signicantly lower damage scores of the femoral components and polyethylene inserts in the oxidized zirconium compared to the CoCr-bearing surfaces.
Further, in a different matched-pair retrieval analysis,
prolometry of 10 oxidized zirconium and 10 CoCr
femoral components showed signicantly greater surface roughness of the CoCr femoral components compared to the oxidized zirconium implants (Heyse etal.
2014). This building evidence shows that enhanced
invivo performance of oxidized zirconium compared to
CoCr-bearing surfaces in TKA.
34.7 Clinical Outcomes
> Oxidized zirconium’s improved wear characteristics
are attributed to its surface lubricity (Bal etal. 2007)
that results in a decreased coefcient of friction, its
increased hardness compared to CoCr, and reduced
in vivo surface roughening compared to CoCr (Bal
etal. 2007).
In order to simulate the degree that roughening of
components contributes to wear, Ries et al. (2002)
intentionally roughened CoCr and oxidized zirconium components and tested their wear characteristics after five million cycles on a knee simulator.
They reported that roughened oxidized zirconium
produced 85% less wear than roughened CoCr (Ries
et al. 2002). Therefore, it appears that all of these
factors play a role in the reduction of polyethylene
wear seen in oxidized zirconium compared to CoCrbearing surfaces.
> Reassuringly, oxidized zirconium does not produce
different polyethylene wear particulate debris compared to CoCr-induced polyethylene wear particles
(Minoda etal. 2014; Kim etal. 2010).
Oxidized zirconium-bearing surfaces also produce reliable patient clinical outcomes and durable implant
survivorship (Innocenti etal. 2010, 2014; Laskin 2003;
Hui etal. 2011; Hofer and Ezzet 2014). Innocenti etal.
(2014) reported a 98% implant survival at 10years and a
mean Knee Society score (KSS) of 84 and a mean Knee
Society function score (KFS) of 83in 98 patients with
oxidized zirconium-bearing surfaces at a mean 11years
of follow-up. Similarly, Hofer and Ezzet (2014) reported
excellent sustained clinical outcomes with mean KSSs
of 92 and KFS of 81 in 109 TKAs with oxidized
zirconium- bearing surfaces.
Conclusion
z
In conclusion, cemented primary TKA remains the gold
standard knee arthroplasty option. Meticulous surgical and cementation technique and avoiding common
surgical pitfalls, as outlined in this chapter, is essential
to achieving well-aligned, well-balanced, and durable
TKAs. Furthermore, oxidized zirconium-bearing articulations show signicant promise in reducing polyethylene wear and may further enhance implant durability
and longevity.
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34
Take-Home Messages
5 Preoperative planning and intraoperative assess-
ment of bony cuts and alignment help ensure that
one achieves a well-aligned TKA.
5 Achieving proper femoral component rotation for
an individual patient’s anatomy while not overresecting the posterior medial femoral condyle is
essential in properly balancing a TKA.
5 Meticulous cement techniques, including pressur-
ization and cementation of the tibial keel and coating of the tibial and femoral implants, are crucial
for xation strength and implant durability.
5 Oxidized zirconium-bearing surfaces in primary
TKA have reduced polyethylene wear compared to
CoCr-bearing surfaces in in vitro knee simulator
studies.
5 Oxidized zirconium-bearing surfaces can result in
up to 98% implant survival at 10years with reliable
and sustained improvement in clinical outcome
measures.
5 Retrieval analyses show that oxidized zirconium
has decreased damage, wear properties, and surface roughness compared to CoCr femoral components.
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Contemporary Rotating Hinged
Prostheses inPrimary Total
Knee Arthroplasty
BenjaminM.Wooster andMatthewP.Abdel
Contents
35.1 Introduction – 396
35.2 Case Example – 396
35.3 Surgical Technique – 396
35.3.1 Exposure – 397
35.3.2 Tibial Preparation – 397
35.3.3 Femoral Preparation – 400
35.3.4 Patellar Preparation – 401
35.3.5 Trialing – 401
35.3.6 Final Implant Placement – 403
35
35.4 Indications forRotating Hinges inPrimary TKA – 403
35.5 Clinical Outcomes – 405
35.5.1 Short- andMid-Term Outcomes – 405
35.5.2 Long-Term Outcomes – 405
35.6 Complications – 405
35.6.1 Early Perioperative Complications – 405
35.6.2 Delayed Complications – 406
References – 407
© 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_35
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35.1 Introduction
The utilization of xed hinged prostheses in TKAs has
been traditionally reserved for complex revision scenarios where issues such as extensive bone loss, ligament
incompetence, and extensor mechanism dysfunction
prevented the use of implants with lesser constraint
(Sculco 2006; Dauwe and Vandenneucker 2018). While
the initial stability afforded by these devices can be benecial in these difcult revision situations, the historically
high failure rate of early xed hinged designs moderated their widespread adoption. The etiology of failure
of older hinged prostheses was likely multifactorial in
nature, but largely related to aws in the biomechanical
design and poor kinematics of these implants (Dauwe
and Vandenneucker 2018; Chelman etal. 1975).
The rst-generation of xed hinged prostheses were
introduced in the early 1950s and consisted of linked,
monobloc components of various metal alloys that
only allowed uniaxial motion in the sagittal plane
(Jones 1973; Shiers 1954; Lettin et al. 1978; Mazas
1973). This degree of constraint resulted in signicantly
increased force transmission to the bone–cement interface yielding unacceptable early failure rates due to
aseptic loosening (Dauwe and Vandenneucker 2018;
Jackson and Elson 1973). Second-generation hinged
prostheses were introduced nearly two decades later
featuring design modications that permitted some
additional motion in the axial and coronal planes
(Sheehan 1978; Herbert and Herbert 1973; Matthews
et al. 1973; Hoogland and Bosma 1981; Flynn 1979).
However, early failure and high complication rates persisted despite these modications (Kester etal. 1988;
Knutson etal. 1986).
Contemporary, third-generation rotating-hinge (RH)
constructs rst appeared in the market in the early 1990s
and incorporated modularity and mobile bearings into
the design (Jones 2006; Barrack 2001). The reduced
prosthetic constraint afforded by these modern implants
functioned to mitigate the forces transmitted to the
bone–cement interface and resulted in increased survival
rates compared to earlier designs.
> Consequently, the indications for RHs have expanded
in both primary and revision TKA scenarios.
35.2 Case Example
A 90-year-old female with a history of right total hip
arthroplasty for primary osteoarthritis presents to clinic
with a chief complaint of progressively worsening left
knee pain, instability, and deformity refractory to con-
servative management strategies. Physical examination
demonstrates a severe, xed, valgus deformity of the left
knee measuring approximately 75° (. Fig.35.1). Passive
and active range of motion is limited from 10° shy of
full extension to 100° of exion. Ligamentous testing
demonstrates complete incompetence of the medial collateral ligament (MCL) with valgus stress (. Fig.35.2).
Radiographs of the left knee demonstrate severe genu
valgus with advanced degenerative changes of the lateral and patellofemoral compartments, lateral subluxation of the patella with erosion of the lateral patellar
facet, and gapping of the medial joint space consistent
with MCL insufciency (. Fig. 35.3). Standing hip–
knee–ankle (HKA) radiographs demonstrate a windswept deformity with moderate varus alignment of the
right lower extremity and signicant valgus alignment
of the left lower extremity (. Fig.35.4).
Given the severe coronal deformity and lack of a
competent MCL, the plan is for a TKA with an RH
prosthesis. Intraoperative evaluation demonstrates
severe tricompartmental arthritis with substantial erosion of the posterolateral tibia and lateral facet of the
patella (.
Fig. 35.5). The patient receives a cemented
Modular Rotating Hinge (MRH) construct (Stryker;
Mahwah, NJ) with cemented tibial and femoral stems.
The postoperative course is uneventful and the patient
has an excellent recovery.
At the most recent follow-up (3years postoperative),
the patient reports signicant improvement in her pain
and function. She is ambulating without the use of gait
aids. Physical examination demonstrates a neutral
mechanical axis of her left lower extremity. Range of
motion of the left knee is from 0° to 130°. Radiographs
of the left knee demonstrate a well-xed and well- aligned
RH TKA (. Fig.35.6). The postoperative HKA radiograph demonstrates neutral mechanical alignment of
the left lower extremity (. Fig.35.7).
35.3 Surgical Technique
Typical anesthesia includes spinal anesthesia, singleshot adductor canal block, and periarticular injection.
Patients are placed on the operative table in the supine
position. An examination of the knee is performed
under anesthesia. Thereafter, a non-sterile pneumatic
tourniquet is placed on the thigh followed by sterile
preparation and draping of the operative extremity.
Prophylactic antibiotics consisting of a weight-based
dose of a second-generation cephalosporin (e.g., cefazolin) and 1g of tranexamic acid are administered intravenously (IV). The limb is then exsanguinated and the
tourniquet is inated.
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a
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. Fig. 35.1 Clinical photographs of patient’s bilateral lower extremities including an anteroposterior view a demonstrating a xed valgus
deformity of the left knee and a lateral view b demonstrating an approximate 10° exion contracture of the left knee
35.3.1 Exposure
A straight midline anterior longitudinal incision is performed with the knee in approximately 90° of exion.
Sharp dissection is carried through the subcutaneous tissue to the level of the fascia. A standard medial parapatellar arthrotomy is performed to expose the knee joint.
If difculty exposing the knee joint is encountered, a
quadriceps snip and/or complete takedown of the collateral ligaments from their femoral insertions are performed to facilitate exposure of the joint (. Fig.35.8).
A medial release is performed around the proximal tibia.
The patella is subluxed or everted laterally and the knee
joint is evaluated. Osteophytes, menisci, and the cruciate
ligaments are excised.
35.3.2 Tibial Preparation
An external alignment guide is used to align the tibial
resection guide perpendicular to its axis in the frontal
plane.
> Of important note, when completing an RH TKA in
the primary setting, additional tibial and femoral
bony resections must be completed to accommodate
the prosthesis, including the hinge mechanism.
Typically, the tibial resection required is 10–12 mm
from the involved side, but varies based upon the preoperative radiographs and intraoperative pathology.
The guide is secured to the tibia with pins and the tib-
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. Fig. 35.2 Clinical photographs of the patient’s left knee demonstrating xed valgus deformity a and medial gapping with valgus stress
testing, indicating complete incompetence of the medial collateral ligament b
ab c
. Fig. 35.3 Preoperative radiographs including anteroposterior a,
lateral b, and sunrise c views of the patient’s left knee demonstrating
marked valgus deformity, advanced degenerative changes of the lat-
eral and patellofemoral compartments, gapping of the medial joint
space consistent with ligamentous insufciency, and lateral subluxation of the patella
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