Keywords
tibial plateau fracture - surgical approach - fibular osteotomy
Tibial plateau fractures are common injuries. They can occur in any age group but
have a bimodal distribution with high-energy injuries usually occurring in young adults
with good bone quality and low-energy fractures that typically occur in elderly patients
with poor bone quality. They are mainly associated with axial, bending, and rotational
forces or combination of these.
Understanding the degree of soft tissue injury around the knee is of utmost importance
regarding the timing of surgical intervention unless a purely percutaneous approach
will be utilized. Although the reduction is technically easier when performed earlier,
surgical delay may be necessary to decrease the risk of wound complications.
The ideal surgical approach should provide exposure of the fracture site that is sufficient
to facilitate both reduction of the fracture and application of the fixation implants,
with minimal risk of complications such as wound healing or infection. Careful dissection
and atraumatic soft tissue handling is necessary to avoid neurovascular injury or
further iatrogenic insult to soft tissues. The choice of approach is dictated principally
by the fracture pattern, with consideration of the soft tissue envelope, patient factors,
and associated injuries (e.g., need for vascular repair or fasciotomies) occasionally
altering the surgical plan. The use of computed tomography (CT) has greatly improved
our ability to understand the pattern of injury.[1] CT scan with sagittal and coronal reconstructions is obtained in all proximal tibia
fractures. If temporizing external fixation is necessary, CT scan is deferred until
after closed reduction and external fixation has been performed. A detailed analysis
of the fracture pattern, especially with respect to fracture plane(s), displacement
of the joint surface, and comminution is necessary to develop a surgical tactic for
fracture reduction and application of fixation implants, which in turn is critical
in deciding the surgical approach(es) to be used.
Early techniques for the treatment of proximal tibial fractures relied on a direct
anterior midline approach, which required large soft tissue flaps to access the corresponding
fracture.[2]
[3] To address associated collateral ligament and meniscal injuries, a modification
using an inverted “L”-type incision over the joint line was described.[4] Over time, the importance of soft tissue management and the correlation of outcomes
with anatomic reduction have led to fracture-specific approaches. The diminishing
use of peripatellar incisions, descriptions of the posteromedial and posterolateral
approaches, and common use of a dual-approach technique are the principle evolutions
since Tscherne and Lobenhoffer published their overview 20 years ago.[5] Commonly used approaches to the proximal tibia, which together allow for the treatment
of any proximal tibia fracture, will be described in this article.
General Considerations
A fully radiolucent table (Mizuho OSI, Union City, CA) is used in all cases. This
allows radiographic evaluation in multiple planes including a joint line view (anteroposterior
[AP] view tilted 10 degrees caudally to be parallel to the posterior slope of the
tibial plateau), oblique views, a true lateral view, and views in line with the fracture
lines that are taken to assess fracture reduction and fixation. A nonsterile tourniquet
is placed as high on the thigh as possible. For a posterior approach, a sterile tourniquet
is applied to ensure that the proximal aspect of the skin incision is not draped out
of the surgical field. In unicondylar fractures, a bump under the hip and torso is
utilized tilting the patient approximately 30 degrees to have access for the exposure
in the resting position. The bump is applied on the ipsilateral side in lateral plateau
fractures and on the contralateral side in medial plateau fractures. In bicondylar
fractures either a small bump or no bump is used because access to both medial and
lateral sides of the leg is necessary. A triangle or bump placed under the leg helps
to avoid the contralateral leg while obtaining the lateral view with the C-arm. The
universal distractor is an extremely useful tool and it is used in the majority of
cases to improve the visualization and the quality of reduction. Reduction clamps,
bone tamps, a lamina spreader, minifragment set, Kirschner wires, and bone void filler
(cancellous allograft or other type of fillers) are planned in addition to the definitive
fixation implant, most commonly a precontoured periarticular plate.
Percutaneous Approaches
Pure split (Schatzker type I) or pure depression (Schatzker type III) fracture patterns
may be amenable to percutaneous approaches. Timing of surgical intervention may be
as early as the day of injury as incisions are limited to 1 to 2 cm. Appropriate fluoroscopic
imaging is of paramount importance in percutaneous surgery as both the adequacy of
reduction and positioning of fixation implants relies on fluoroscopy.
For pure split fractures the reduction is achieved using periarticular clamps with
ball-spike tips. The prongs of the clamps are placed at the medial and lateral side
1 to 2 cm below the joint line through small incisions. Disc attachments may be used
to increase the surface area of the tips of the clamps while applying compression,
especially in osteoporotic bones. Then, the reduction is confirmed using fluoroscopic
imaging in both AP and lateral joint line views. Multiple guide wires for appropriate
cannulated screws are placed adjacent to the subchondral bone and parallel to the
joint line. Fixation is usually accomplished with multiple (at least three) 6.5/7.0-mm
lag screws. Washers may be used to avoid penetration of the screw head into the bone
thus increasing surface area of compression of screws.
For pure depression type of fractures, the goal is to elevate the depressed portion
of the joint surface to the anatomic level. A 2- to 3-cm incision is created at the
anterolateral proximal tibia usually 4 to 5 cm below the joint line. A bone window
of 1-cm diameter is created using a 2.0- or 2.5-mm drill bit and a chisel to connect
the drill holes. Alternatively, a bone tamp can be used to create a window on the
cortex by pushing the cortex into the metaphyseal area with a mallet. Bone tamps are
then used to elevate the depressed joint surface. It is critical to check the location
of the fracture in both AP and lateral fluoroscopic views to correctly place the bone
tamp under the depressed joint surface as relying on one view can easily be misleading.
Undue force should be avoided while using bone tamps, as inadvertent entry into the
joint is a pitfall of this technique. The void created by the reduction of the depressed
joint surface and the tract used by the bone tamp is filled with cancellous allograft
or a bioabsorbable cement to support the elevated joint surface. Then, multiple 3.5-mm
cortical screws are placed percutaneously using a “rafter” technique to further support
the reduction.
In addition to fluoroscopic imaging, arthroscopy is a tool that can be useful for
direct visualization of the joint surface and assessment of the accuracy of reduction.
One should be aware of extravasating fluid used during arthroscopy through the fracture
site into the leg compartments, potentially resulting in compartment syndrome. Therefore,
repeated examination of the leg throughout the surgical intervention and postoperatively
is warranted, as well as limiting the amount of time that arthroscopy done, and using
gravity for fluid inflow instead of an irrigation pump.
On the basis of the surgeon's preference, pure split (Schatzker type I) and pure depression
(Schatzker type III) fractures can also be treated with open anterolateral approach.
In our experience, open approaches provide more consistent reduction and fixation
in the split-depressed facture pattern (Schatzker type II) and bicondylar fracture
variants (Schatzker type V and type VI).
Anterolateral Approach
Because most tibial plateau fractures involve the lateral tibial plateau, an anterolateral
approach is the most frequently used approach for the treatment of plateau fractures
([Figs. 1]
[2]
[3]
[4]). This approach is typically utilized for split-depression lateral plateau (Schatzker
type II) and bicondylar (Schatzker type VI, type V) fracture patterns. When an unstable
tubercle fragment is encountered, a separate small anterior incision can be added
for direct reduction and fixation of the tubercle.
Fig. 1 Anterolateral approach: The incision starts 2 to 3 cm proximal to the joint line
crossing the Gerdy tubercle and aiming 1 cm off the lateral border of the tibial crest
extends 3 cm below the inferior margin of the tibial tubercle, and can be extended
as far distally as needed. P, patella; TT, tibial tuberosity; FH, fibular head.
Fig. 2 Anterolateral approach: (Top) Retraction of the skin and subcutaneous tissue exposing
the Gerdy tubercle (GT), iliotibial (IT) band, and fascia of the anterolateral leg.
(Middle) The IT band and leg fascia are incised in line with skin incision and kept
in continuity, detaching the IT band off GT sharply. (Bottom) With anterior and posterior
retraction of IT band leg fascia and reflection of the origin of tibialis anterior
from the proximal tibia, the split fracture and capsule is exposed.
Fig. 3 Anterolateral approach: (Top) After submeniscal arthrotomy leaving a cuff of tissue
on the tibial side, sutures are placed through the meniscus and capsule. (Middle)
Application of the universal distractor. (Bottom) With application of distraction
and retraction of the meniscocapsular tissue using sutures, the depressed joint surface
is visualized.
Fig. 4 Anterolateral approach: (Top) The sutures are passed through the K-wire holes in
the periarticular plate. (Middle) Once the plate is apposed to the bone, a periarticular
clamp is applied across the proximal tibia at the level of the subchondral bone through
a small incision on the medial side and on one of the screw holes on the plate. (Bottom)
Clamping assures the reduction of the width of the tibial plateau as well as compression
across the fracture lines at the level of the joint.
Superficial Dissection
Two slight variations in the skin incision can be used. The incision starts from 2
to 3 cm proximal to the joint line and extends 3 cm below the inferior margin of the
tibial tubercle, and can be extended as far distally as needed. The lazy “S”-shaped
incision starts direct lateral over the iliotibial (IT) band, curves over Gerdy tubercle
(GT), and continues distally 1-cm lateral to the tibial crest. Alternatively, a gentle
curvilinear incision centered over GT can be created. Starting at the center of GT,
the IT band is cut in line with the fibers proximally. Distal to the GT, the fascia
of the anterior compartment of the leg is incised in continuity with the IT band incision,
aiming toward the lateral border of the tibial tubercle and tibial crest. The IT band
is detached from its insertion using sharp dissection with a knife and reflected anteriorly
and posteriorly. The interval between the IT band and the joint capsule is developed
with blunt dissection and care is taken to keep the capsule intact. Distally, the
anterior compartment fascia is incised.
If visualization of the joint (i.e., a submeniscal arthrotomy) is not planned, a hockey-stick
skin incision can be utilized for minimally invasive application of plate fixation.
The proximal limb of the incision is parallel to the joint line, curving over the
GT and aiming distally 1 cm off the lateral border of the tibial crest.
Deep Dissection
The origin of the tibialis anterior muscle is reflected from the proximal lateral
tibia and retracted posteriorly exposing the anterolateral surface of the proximal
tibia. The joint line is identified by direct palpation. A submeniscal arthrotomy
is created to directly visualize the articular cartilage. Leaving a cuff of tissue
on the tibial side for repair, the meniscotibial ligaments are incised along the tibial
border similar to that described by Padanilam et al[6] but without dividing the anterior horn of the meniscus. Three or four sutures are
placed through the peripheral meniscus in a vertical fashion and used to apply retraction
to improve the visualization of the articular surface. These sutures are then used
for direct repair to the aforementioned cuff of tissue on the tibial side. Alternatively,
they are passed through the small K-wire holes in the periarticular plate before securing
the plate to bone and the sutures are tied over the plate. If a peripheral vertical
lateral meniscal tear exists, which are commonly associated with joint depression
fracture patterns, multiple sutures are passed in vertical fashion through the inner
part of the meniscus and through the capsule, thus incorporating the meniscal repair
into the repair of the submeniscal arthrotomy.
To aid in direct visualization of the articular surface, a universal distractor is
applied with either 5.0- or 6.0-mm Schanz pins depending on the size of the bone.
The femoral pin is placed 1 to 2 cm proximal to the lateral epicondyle at the level
of metaphyseal flare. The tibial pin is placed 1 to 2 cm beyond the distal extent
of plate that will be applied for fixation. Planning of the length of the plate to
be used before the placement of the tibial Schanz pin is important so that the distractor
does not interfere with application of definitive fixation. This is determined by
selecting the appropriate plate and obtaining a fluoroscopy image with the plate overlying
the leg. The bar of the distractor is usually placed posteriorly. When an external
fixator has already been placed as part of a staged-treatment protocol, the Schanz
pins of the external fixator can be used for application of the universal distractor.
Additional Exposure
The incision can be extended distally and used to decompress the anterior and lateral
compartments of the leg, or for fixation of fracture extension into the tibial shaft
if needed.
Medial Approach
Here, we differentiate medial and posteromedial approaches. The medial approach is
used for isolated fractures of the medial plateau (Schatzker type IV) and as part
of the “dual incision approach” for bicondylar fractures ([Fig. 5]).[7]
[8]
[9] This approach is appropriate when the unstable fragment is the anterior part of
the joint and the fracture line is parallel to the anteromedial surface of the tibia
or approximately in the coronal plane. The fixation is placed on the anteromedial
surface of the tibia therefore having the screws crossing the fracture line perpendicularly.
Fig. 5 Medial and posteromedial approaches. The skin incision for the medial approach starts
2 to 3 cm above joint line and is in line from the medial femoral epicondyle aiming
bisecting posteromedial border of tibia and the tibial crest. The skin incision for
the posteromedial approach starts 2 to 3 cm above joint line and follows the posteromedial
border of tibia.
Superficial Dissection
The skin incision starts 1 to 2 cm proximal to the joint line in line with the medial
femoral epicondyle and extends over the pes anserinus insertion, bisecting the tibial
crest and the posteromedial border of the proximal tibia. The length of the incision
is based on the metaphyseal extent of the fracture. The saphenous nerve and vein are
generally posterior to this incision but caution should be used, as anatomic variations
exist. With the knee bent 15 degrees, a straight incision is made 10 to 15 cm in length.
Warren et al described the medial knee structures to be in three layers.[10] Just deep to the subcutaneous tissues, the sartorius fascia is encountered and incised
in line with the skin incision. Distally, the gracilis and semitendinosus tendons
are identified coming from posterior to their insertion on the anteromedial tibia.
Deep Dissection
The pes anserinus tendons are skeletonized proximally and distally. This exposes the
second layer, which contains the superficial medial collateral ligament (MCL). If
necessary, the pes tendons can be taken down for fracture reduction and later repaired.
The broad insertion of the deep MCL (third layer[10]) makes arthrotomy and direct joint line visualization impractical. Indirect reduction
is performed, and fixation is accomplished by direct application of plate over the
MCL structures without elevation or mobilization.
Additional Exposure
This incision can be extended distally for a fasciotomy of the posterior compartments
of the leg or for fixation of fracture extension into the tibial shaft as necessary.
Posteromedial Approach
This is an ideal approach for the typical shear fractures of medial tibia plateau,
when the fracture line is in or close to the coronal plane and buttress plating is
required with placement of fixation on the posterior or posteromedial surface of the
medial tibial plateau. This approach is also used for shear fractures when the fracture
line is in or close to the sagittal plane and buttress plating is required with placement
of fixation on the medial surface (at the junction of the posterior and anteromedial
surface in cross section) of the tibial plateau. The Moore type I fracture has no
specific designation in the Schatzker system, however, Barei et al found that nearly
40% of 41 C-type fractures have such a pattern.[9] This approach can be done in the supine[11]
[12]
[13] or prone[8]
[14] positioning. Prone positioning has the advantage of being ergonomic for the surgeon
and easily permits the axial traction and extension/hyperextension of the knee with
the gravity that aids in indirect reduction.[3]
[8] It is not recommended when there is involvement of the lateral plateau (in a dual
approach strategy) as it requires repositioning of the patient, and adjustment to
the initial fixation is not possible once the patient is turned supine for exposure
of the fracture on the lateral plateau.
Posteromedial Approach (Supine)
Superficial Dissection
In the supine position with the leg externally rotated, a longitudinal incision along
the posterior margin of the tibia is made (this is 1–2 cm more posterior than the
medial approach) ([Fig. 6]).[12]
[13]
[15]
[16] The incision starts 3 cm proximal to the joint line and extends as far distally
as needed. The saphenous nerve runs just anterior to the great saphenous vein. Both
should be protected during exposure. Branches of the greater saphenous vein are ligated
to retract it with the anterior or posterior flap. The sartorius fascia is incised
in line with incision.
Fig. 6 Posteromedial approach: (Top) Incision of the sartorial fascia exposes the pes tendons,
which are freed for retraction distal-posterior or proximal-anterior. (Bottom) The
medial collateral ligament is incised at the posterior edge (retracted with a rake),
the popliteus muscle insertion is reflected from the posterior border of tibia (retracted
with Hohmann posteriorly), and the pes tendons is retracted distally exposing the
common site of the fracture line exit at the metaphysis (marked).
Deep Dissection
The fracture line exits commonly at the level of the pes tendons at the metadiaphysis.
The pes anserinus tendons are mobilized and retracted distal-posterior or proximal-anterior,
whereas the medial gastrocnemius (MG) and soleus are retracted posteriorly. This exposes
the junction between the popliteal fascia (posterior and distal), the semimembranosus
(SM) insertion (posterior and proximal), and the MCL. Staying on the posterior border
of the MCL, the periosteum is incised sharply longitudinally down to the bone. The
proximal exposure is limited by the insertion of the SM. The SM is a broad attachment
over the proximal posteromedial tibial plateau including continuity with the posterior
medial meniscus. Using subperiosteal dissection, the popliteus muscle insertion is
elevated off the posterior tibia to allow for direct visualization of the triangular
apex of the fracture at the metadiaphyseal level, which allows indirect reduction
of the joint and fixation with buttress plating. Subperiosteal dissection is critical
as it avoids injury to the neurovascular structures including inferomedial genicular
vessels. Reduction of the joint line is generally done indirectly by direct reduction
of the apex and confirmed using fluoroscopic imaging, however, a posterior arthrotomy
with elevation of the medial meniscus has been described.[13]
[15]
[16] This arthrotomy requires extension of the subperiosteal dissection proximally, with
elevation of the SM off the posteromedial tibia. Once the meniscotibial attachment
is identified, a cuff is left on the tibia and stay sutures are placed for retraction
and later repair. This is a far more limited visualization of the joint surface as
compared with the lateral meniscal arthrotomy even with the use of a medially placed
universal distractor. As most of the medial plateau fractures consist of simple fracture
lines, indirect reduction of the joint line is the mainstay of our posteromedial approach.
The reduction of the joint line is confirmed using fluoroscopic imaging. Assessment
of the reduction can also be performed with arthroscopy. If direct visualization of
the medial tibia plateau is deemed necessary for depression of joint surface, a medial
parapatellar arthrotomy may provide a better exposure.
Additional Exposure
This incision can be extended distally for a fasciotomy of the posterior compartments
of the leg or for fixation of fracture extension into the tibial shaft as necessary.
Posteromedial Approach (Prone)
This technique was first described in the German literature by Galla and Lobenhoffer,[14] for treatment of isolated Moore type I tibial plateau fractures, as an alternative
to the posterior approaches that traversed the popliteal fossa ([Fig. 7]). It was later described by Fakler et al[8] in the English literature. The patient is positioned prone with a small contralateral
hip bump. A folded blanket is placed beneath the ipsilateral thigh to allow for hyperextension
which, as noted by Moore,[3] aids in the reduction of the fracture. A tourniquet is placed high on the thigh.
Fig. 7 Posteromedial approach in prone position: Retraction of the medial head of gastrocnemius
laterally and pes tendons medially and reflection of the popliteus muscle insertion
from the posterior medial proximal tibia laterally provides a direct view of the posteromedial
tibia. (Reprinted with permission from Canale ST, Beaty JH. Campbell's Operative Orthopaedics.
12th ed. Copyright © 2012 Mosby, An Imprint of Elsevier.)
This approach is ideal for shear fractures of the posterior medial plateau when the
fracture line is in the coronal or coronal–oblique plane. On the contrary, it should
be limited to isolated fractures of the medial plateau because the adjustment of the
reduction and fixation is not possible once the patient is turned supine for exposure
of the lateral plateau.
Superficial Dissection
The skin incision is more posterior and lateral than that of the supine position.
It is created longitudinally 8 to10 cm in length starting just above the joint line
and running along the medial border of the MG.
Deep Dissection
The MG is retracted laterally and is used to carefully protect the neurovascular structures
that run deep and lateral to its muscle belly. The interval between the MG and the
SM is developed without the need to dissect out the pes tendons anteriorly. The subperiosteal
dissection is essentially the same, with sharp dissection of the popliteal fascia
medially and subperiosteal elevation of the popliteus muscle off its insertion from
the proximal posterior medial tibia starting from distal and proceeding proximally.
Additional Exposure
To gain additional lateral exposure, De Boeck and Opdecam described an “S”-type incision
which starts proximally over the middle to lateral border of the MG, curves gently
over the joint line and continues along the posteromedial border of the tibia.[17] A partial release of the origin of the MG improves exposure of the posterior tibia.
We reserve this approach for comminuted posterior/posteromedial fractures, and any
instance in which the posterior cruciate ligament (PCL) is compromised (as reconstruction
can be done from this extended exposure[11]).
Posterolateral Approach
The principal indication for this approach is a coronal fracture line resulting in
a displaced posterolateral fragment ([Fig. 8]).[7]
[18]
[19] This approach should be reserved to fracture patterns that cannot be addressed through
the anterolateral approach because of the risk of complications including stiffness
and peroneal nerve injury. Posterolateral fractures of tibial plateau are not specifically
accounted for in the common classification systems. Although described as “rare” injury
patterns, retrospective studies have observed a 7 to 10% incidence in operatively
managed proximal tibial fractures.[19]
[20]
[21] Solomon et al reviewed nine such cases treated by way of an anterior or anterolateral
approach, and noted that none achieved anatomic reduction.[19] They subsequently changed techniques, and a retrospective analysis at 2-year follow-up
demonstrated superior clinical and radiographic outcomes with the use of a posterolateral
approach.[22] Extensive soft tissue dissection is required, however, and flexion contractures
of 5 to 10 degrees have been seen in upward of 50% of the patients.[18]
[23]
Fig. 8 Posterolateral approach without fibular osteotomy: This approach should be limited
to fractures that cannot be addressed through other approaches such as shear fractures
of the posterolateral plateau amenable for buttress plating. (Reprinted from Frosch
KH, Balcarek P, Walde T, Stürmer KM. A new posterolateral approach without fibula
osteotomy for the treatment of tibial plateau fractures. J Orthop Trauma 2010;24(8):515–520,
with permission from Lippincott Williams and Wilkins.)
The technique was described by Lobenhoffer et al in 1997[7] and numerous variations have appeared since then, the principal difference being
the presence[7]
[19] or absence[15]
[18]
[23]
[24]
[25] of a fibular osteotomy. Proponents of the osteotomy cite the improved exposure of
the lateral and posterolateral joint line as the principal advantage[19]; however, dissection of the peroneal muscle origin, posterolateral ligamentous structures,
and need for osteotomy repair are all additional sources of complication.[26] As such, we use the fibular sparing approach as described by Carlson.[24] An excellent English description of the osteotomy technique is published[19] and will not be described here.
The patient can be positioned in the prone,[7]
[18]
[23]
[24] supine,[19] or lateral position.[25] Supine positioning is more technically demanding and requires the use of a sand
bag or foot holder to flex the knee without blocking the popliteal fossa. We reserve
this for the rare instance when additional anterior intervention is required, as in
the case of an ipsilateral shaft fracture requiring intramedullary nailing.
Positioning
A thigh tourniquet is applied before draping. The patient is placed in the prone position
on bolsters. A small bump is placed under the operative thigh. This elevates the limb
for lateral radiographs and allows for hyperextension during reduction.
Superficial Dissection
A straight 10-cm longitudinal incision is made from the medial aspect of the biceps
femoris (BF) tendon proximally to the posteromedial border of the fibula distally.
Dissection is carried through skin, subcutaneous tissue, and popliteal fascia. The
interval between the BF and lateral gastrocnemius (LG) muscle is palpated. At the
proximal most aspect of this, the fat streak containing the common peroneal nerve
(CPN) can be identified just medial to the BF. The CPN gives off the lateral sural
cutaneous nerve (LSCN) at this level. The plane of dissection is between the LG, which
will be retracted medially with the LSCN, and the BF which will be retracted laterally
with the CPN. The CPN runs along the inferior medial border of the BF as it travels
distally. It perforates the posterior intermuscular septum just below the insertion
of the BF on the fibula and dives into the peroneal tunnel. The nerve must be mobilized
over the entire length and retracted laterally for protection.
Deep Dissection
The LG is the limiting factor for medial exposure. Depending on the fracture pattern,
its origin can be left intact, partially elevated (from inferior lateral to superior
medial), or released and repaired later. Distally, the soleus is encountered at its
origin on the posterolateral tibia and fibula. Blunt elevation of the soleus will
provide exposure of the proximal tibia. Distal exposure should be limited to 4 to
5 cm below the joint line to avoid injury to the anterior tibial artery, which travels
laterally through the intermuscular septum to the anterior compartment (approximately
5–7 cm below the joint line). Care is also taken when releasing the soleus from the
fibular neck to avoid injury to the CPN. The popliteus muscle and tendon are usually
coursing over the proximal joint line at the level of the fracture. Before mobilizing
this structure, the inferolateral genicular artery should be identified. It runs just
inferior to the popliteus muscle-tendon structure and travels deep to the fibular
collateral and popliteus-fibular ligaments as it courses anteriorly. If observed,
the vessel should be ligated before proceeding. Finally, the posterior capsuloligamentous
complex is incised from medial to lateral. Stay sutures are placed for retraction
and later repair.
Additional Exposure
Posterolateral fractures can occur in combination with the common central and/or anterior
fractures of the lateral plateau. In these instances, the subcutaneous dissections
of the anterolateral and posterolateral approaches can be combined through a single
incision as described by Frosch et al.[25] The skin incision is made directly along the femoral condyle and the proximal fibula
(bisecting between that of the anterolateral and posterolateral exposures). The deep
dissection is performed as described above. In this manner, the CPN will lie between
the two surgical exposures, and extra care must be taken to avoid iatrogenic injury.
Direct Posterior Approach
Direct Posterior Approach
Because of the risk of iatrogenic injury to neurovascular structures in the popliteal
fossa and risk of flexion contracture, the direct posterior approach should be limited
to the fracture patterns that cannot be addressed with posteromedial and/or posterolateral
approaches ([Fig. 9]). The injury pattern most commonly treated with this approach is a shear fracture
of the posterior plateau with main fracture line in coronal plane or avulsion of PCL
insertion with a fracture line extending into the large articular surface. The original
approach was described by Abbott and Carpenter in 1945[27] as a midline approach with careful dissection of all popliteal structures. Over
time, several variations including a MG splitting,[28] “S-”shaped curvilinear,[29] and medially based inverted “L-”type incision[11] have been described for treatment of soft tissue abnormalities (PCL injury, Baker
cyst, or pigmented villonodular synovitis); however, only one report focuses specifically
on the use of this approach for management of posterior tibial plateau fractures.[20] A detailed, pictographic, description of the landmarks and relative anatomy of the
posterior approach in a cadaver series was also recently published.[30]
Fig. 9 Direct posterior approach: (Left) An “S-”shaped incision is created along the biceps
femoris tendon proximally, then curving across the popliteal fossa at the joint line
and distally along the medial head of the gastrocnemius muscle. (Right) Lesser saphenous
vein and medial cutaneous sural nerve is on the medial side, tibial nerve is in the
middle with retraction of the lateral head of the gastrocnemius.
Superficial Dissection
An “S-”shaped incision is created along the BF tendon proximally, then curving across
the popliteal fossa at the joint line and distally along the medial head of the gastrocnemius
muscle. The incision is made carefully through the skin only. At, or just below, the
joint line the lesser saphenous vein and sural nerve are identified piercing through
the popliteal fascia. The sural nerve can be followed proximally and used as a landmark
for safely identifying the tibial nerve. Then, the fascia between the sural nerve
and medial head of the gastrocnemius is incised. The tibial nerve is followed proximally
to the point where the SM and BF meet. On the medial edge of the BF lies the CPN which
should be mobilized and retracted laterally.
Deep Dissection
The vascular structures run medial to the tibial nerve. The popliteal vein is lateral
to the artery at the level of the femur, crosses superficial to it at the joint line,
and runs medial to it along the tibia. Depending on the fracture pattern and exposure
required, one or more of the five genicular branches may need to be ligated for adequate
exposure and mobilization of the popliteal artery. If either head of the gastrocnemius
is mobilized, the corresponding superior genicular artery may need to be ligated.
Flexion of the knee can reduce tension on the medial genicular artery and avoid injury
to this vessel when working near the center of the joint line.
The deep dissection is the same as that described above for the posteromedial and
posterolateral approaches, with mobilization of the MG, or detachment of the LG and
mobilization of the BF.
Additional Exposure
When concern for vascular injury necessitates, the distal aspect of the incision can
be extended and the terminal divisions of the popliteal artery can be identified superficial
to the popliteus muscle.
Summary
An ideal surgical approach should allow visualization and reduction of the fracture
and application of fixation with minimal risk of complications such as neurovascular
injury and wound-healing problems. Although the anterolateral approach is the most
commonly applied technique, having the knowledge of different approaches in the armamentarium
is necessary to treat the vast array of fracture patterns that occur in the proximal
tibia. Dual approaches combining anterolateral and posteromedial exposures are the
mainstay choice for most bicondylar tibial plateau fractures. A detailed analysis
of the fracture pattern should dictate the choice of the appropriate approach for
specific fractures.
