The knee is the largest joint in the body. Knee function requires stability, range of motion in bending and rotation, and transmission of large muscular loads (2). The tibia is the major weight bearing bone of the knee joint. At its proximal articular surface, the tibia widens to form the medial and lateral condyles. Between the condyles, the intercondylar eminences serve as the sites of attachment for the fibrocartilaginous menisci and the anterior and posterior cruciate ligaments (3). The relatively flattened condylar portions of the proximal tibia comprise the weight bearing aspects of the tibial plateau. The medial and lateral tibial condyles articulate with corresponding medial and lateral femoral condyles. Anatomically, the medial tibial plateau is larger and stronger than the lateral tibial plateau (4). This finding may explain why fractures of the lateral condyle occur more frequently than medial condyle fractures (4).

With regard to epidemiology, fractures of the tibial plateau constitute approximately 1% of all fractures (5) and generally result from trauma such as a fall or motor vehicle versus pedestrian accident. Approximately 5% to 10% of tibial plateau fractures are sports related (6) and this incidence is higher in skiers (5).

With regard to mechanism of injury, fractures involving the tibial plateau can result from medial, lateral, or axially directed forces. Forces directed medially (valgus force moment) are often classic “bumper fractures:” motor vehicle versus pedestrian accidents. More complex mechanisms involve combinations of both axial and varus or valgus directed forces. In most cases, the medial or lateral femoral condyle acts as an anvil imparting a combination of both shearing and compressive force to the underlying tibial plateau (4).

A patient with a fracture of the tibial plateau generally presents with a painful swollen knee injured in some traumatic event (6). Usually, the patient is unable to bear weight on the affected leg (3), although this is not always the case (6). Occasionally, the patient can accurately describe the precise mechanism of injury, as in “bumper” injuries or accidents sustained playing football or soccer, during skiing, or in a fall. Often, however, this is not the case (3).

Despite the common inability to rely on a patient’s history when determining the specific mechanism of injury of tibial plateau fractures, it is useful to ascertain the level of force involved in the injury, specifically high-energy or low-energy forces (3). This is not a purely academic point; associated injuries such as fracture blisters, compartment syndromes, disruptions of the menisci or ligaments, or injuries to adjacent nerves and blood vessels occur most often in association with high-energy forces (3).

On examination of the affected extremity, one generally finds a distinct limitation of both active and passive knee motion because of pain and swelling. Additionally, voluntary or involuntary muscle guarding or spasm may make it difficult to evaluate the status of the ligaments or the extent of the fracture. Despite this limitation, an effort to examine the patient to determine associated ligamentous damage is recommended. In all cases, careful attention must be paid to peripheral pulses, neurological function, and the status of the compartments of the injured extremity. Any open wounds must be carefully evaluated to ascertain their relationship to the fracture site or joint space (3).

The ultimate goals of tibial plateau fracture treatment are to re-establish joint stability, alignment, and articular congruity while preserving full range of motion. In such a case, painless knee function may be obtained and posttraumatic arthritis could be prevented (4,7).

When articular compression or fracture displacement exists, surgery is required to restore joint congruity and alignment, to stabilize the knee, and to allow early joint motion (6,7). Recommendations regarding absolute indications for operative versus non-operative management vary. We believe that surgery is indicated for articular compression or fragment displacement greater than or equal to 4 mm. In addition, in cases of non-displaced but unstable fractures, rigid internal fixation may still be considered for active patients and athletes in whom early range of motion is a priority.

In our experience, the tibial plateau fracture patterns that may be most amenable to ARIF include Schatzker Types I to IV (fractures with split, split/compression, or pure compression) (10) as well as tibial intercondylar eminence avulsions (14), which are discussed separately in the following section. We acknowledge that percutaneous lag or buttress screws, percutaneous plates, or even open buttress plating may be required in such cases, and we specifically define ARIF as surgery where anatomic reduction and rigid internal fixation is achieved without a large or submeniscal arthrotomy.

More complex or higher-energy injury patterns (Schatzker Types V or VI) (10) may not be amenable to arthroscopic treatment (7,8). In addition, our recommendation is that although ARIF is the definitive treatment for Type III (central compression) fractures, ORIF may have advantages over ARIF in some Type I, II, and IV fractures. In cases where ORIF is preferred, arthroscopy remains useful both for diagnosis and for treatment of associated intra-articular pathology (7).

Potential disadvantages of ARIF or arthroscopic-assisted ORIF of tibial plateau fractures require consideration. Even with the use of a tourniquet, bleeding from the fracture site makes arthroscopy technically difficult. Although this challenge can be to some degree mitigated with the use of a pump, increased pump pressure compounds another problem: extravasation of arthroscopic fluid (15).

With the exception of isolated Type III compression fractures or intercondylar eminence avulsions, the tibial plateau fracture clefts are direct conduits linking the knee joint to the compartments of the leg. The complication of iatrogenic compartment syndrome requiring fasciotomy, always a concern in knee arthroscopy, is associated with traumatic or iatrogenic capsular disruption. This complication must be attentively considered in all cases of arthroscopic treatment of upper tibia fractures. Iatrogenic compartment syndrome requiring fasciotomy has occurred in the experience of the primary author (unpublished data).

A disadvantage of limited visualization of the submeniscal surface of the tibial articular surface has also been described (16). In our experience, specially designed meniscal (double hooked, self-retaining) retractors (Arthrex, Inc., Naples, FL) allow adequate visualization.

After confirming that the patient is otherwise stable, tibial plateau fractures may be addressed surgically without delay; however, a delay from seven to as long as 14 days could be permitted if circumstances dictate. Greater delays could result in early fracture healing, complicating the procedure.

In the case of open fractures, irrigation and debridement (I & D) is recommended on an urgent basis (as in the case of all fractures). Reduction with internal fixation may be performed at the time of I & D unless other issues (gross contamination or poor soft tissue coverage) suggests staged management could be preferred. Other exceptions to urgent treatment are similar, involving issues of soft tissue coverage, severe soft tissue swelling, or other medical or surgical patient issues. In such cases, temporary indirect external fixation with traction often facilitates staged definitive treatment.

Our recommended techniques represent modifications of techniques described by Caspari (17) and by Buchko and Johnson. (7). Operative treatment must be designed specifically for each fracture type (7). We recommend ARIF for central compression (Schatzker Type III) fractures, and we recommend consideration of ARIF for split and split compression fractures (Schatzker Types I, II and IV). Prior to surgery, an examination of the knee under anaesthesia may be of value for ligament evaluation (17).

We recommend the use of a circumferential leg holder and tourniquet. The fluoroscope (C-arm) is turned upside down so the flat (image acquiring) plate may be used as an operating table under the knee. Standard anterolateral (viewing) and anteromedial (instrumentation) portals are utilized. Often, the scope is placed anteromedially to view lateral fractures. The instrumentation or accessory portals may accommodate a hooked meniscal retractor (Arthrex, Inc.) in cases of peripheral and submeniscal pathology.
These blunt, double-hooked retractors may be used in a self-retaining mode with single-use, spring-loaded suction cup, which also prevent fluid extravasation.

Thorough lavage is required in order to remove hemarthrosis or grossly loose and small osteochondral fragments. When possible, reduction of the fracture may be performed in a dry field to decrease the risk of fluid extravasation and increased compartment pressures. In all cases, inflow pressure is kept to a minimum and the compartments are carefully and continuously palpated to assess pressure. This is especially important in split fractures where fluid extravasation occurs directly through the fracture lines. In cases of suspected increased pressures, formal measurement is recommended as is fasciotomy should frank compartment syndrome result.

Split fractures are reduced first. Reduction forceps are recommended, and sometimes an open incision (but not an arthrotomy) is required. Fluoroscopy may supplement the arthroscopic assessment of fracture reduction and is required for placement of wires for provisional split fracture reduction. For Type I fractures, percutaneous, cannulated lag screws may be placed over the wires. If mild fragment instability is suspected, a buttress screw, often used with a washer, is placed at the inferior apex of the split fragment. If greater instability or poor bone quality is of concern, buttress plates may be percutaneously placed or placed through traditional, extra-articular secondary incisions.

In Type II and Type IV fractures, compressed elements must be addressed prior to definitive fixation. Under arthroscopic guidance, an ACL guide with a modified spoon shaped tip (to mimic the curve of the femoral condyle) (Arthrex, Inc.) is used to place a 2.4 mm drill tipped guide pin (Arthrex, Inc.) in the center of the compressed fragment through a small incision in the proximal anteromedial tibial metaphysis. (A lateral approach muscle splitting can be considered for lateral fractures). A coring reamer is used to fully and circumferentially penetrate the tibial cortex while removing as little bone as possible. A cannulated tamp, specially angulated so the leading flat surface is parallel to the plateau (Arthrex, Inc.), is used to elevate the fracture site under direct arthroscopic visualization. Sometimes, it is helpful to over-reduce the fracture, and then place the knee through a range of motion to allow the femoral condyle to anatomically mold the tibial plateau. The underlying metaphyseal bone and cortical disc serve as autograft. In addition, the resulting cortical defect may be grafted using bone autograft, allograft, or bone substitute. Our current preference is freeze dried allograft croutons.

For most Type III patterns, cannulated screws may be introduced percutaneously, directly under the subchondral plate, to buttress the elevated fragments. In addition to the use of fluoroscopic guidance, the fracture guide wires may be placed while the cannulated tamp is still in place. If the wire hits the tamp, this directly confirms accurate screw placement beneath the compression fracture. The tamp may then be removed and the guide wire and ultimate cannulated screw(s) be placed using standard technique. In cases of Type II or Type IV fractures, similar cannulated lag screw techniques will buttress the compression and provide rigid internal fixation of the split fragment. A buttress screw or screw and washer can be additionally placed at the inferior apex of the split fragment. Again, if greater instability or poor bone quality is of concern, buttress plates may be percutaneously placed or placed through traditional, extra-articular secondary incisions.

Associated injuries are common with fractures of the tibial plateau and may include injury to the menisci, ligaments, or articular surfaces of the femur, tibia, or patella (5). Although tibial plateau fractures may occur as isolated lesions, concurrent injuries are the rule (5). In cases of disruption of the lateral collateral ligament complex, injuries to the peroneal nerve or the popliteal vessels may be associated with greater frequency (4).

Up to 47% of knees with closed tibial plateau fractures have injuries of the menisci that may require surgical repair (18); it is difficult to predict the degree of meniscal injury based upon fracture pattern alone (6). Up to 32% of knees with tibial plateau fractures have complete or partial tears of the anterior cruciate (5).

The tibial intercondylar eminence is often avulsed in association with fractures of the tibial plateau (14). In addition, isolated tibial intercondylar eminence avulsion fractures may be considered a unique fracture. Tibial intercondylar eminence fractures are discussed in the following section.

Arthroscopy is a valuable tool for the assessment of tibial plateau fractures and is the treatment of choice for associated intra-articular pathology. In addition, ARIF of selected tibial plateau fractures allows achievement of anatomic reduction and rigid internal fixation with less morbidity than ORIF and with the advantage of superior visualization of the entire joint. We recommend ARIF for Type III fractures and consideration of ARIF for Types I, III, and IV. Some authors have applied ARIF to more complex (Type V or VI) fracture patterns. Published outcome studies of ARIF of tibial plateau fractures describe results that appear to equal outcomes of ORIF, but these studies suffer from extreme susceptibility bias. Future study of ARIF of tibial plateau fractures will require more rigorous descriptions of patient selection (inclusion and exclusion) criteria to allow comparison of arthroscopic and open treatment.

To review, the tibia serves as the major weight-bearing joint of the knee. Within the joint, the proximal tibia widens to form a shelf flanked by the medial and lateral condyles. This shelf is the intercondylar eminence which serves as the point of attachment for the menisci and the anterior and posterior cruciate ligaments (3).

With regard to epidemiology, fractures isolated to the intercondylar eminence are most often seen in children and adolescents (20), although adults may be affected as well (19).

With regard to mechanisms of injury, a fracture of the tibial eminence is a consequence of ACL avulsion at its insertion on the tibia (21) and is an unusual occurrence in adults (16). In this specific scenario, the ACL is pulled from the tibia at the site of attachment with a piece of the bony tibial plateau. This particular problem is relatively common in children and equivalent to rupture of the ACL in adults. The underlying distinction between the pathology in children and adults is that children have a relative weakness of the incompletely ossified tibial eminence which fails before the relatively stronger ligament fails at times of pathology-inducing stress on the knee (22). This is all a consequence of greater elasticity of ligaments in the pediatric population (23).

Besides disrupting the ACL integrity, this fracture affects the articular surface of the tibia, as noted above. This fracture usually occurs between ages 8 and 14, and almost one half of these tibial eminence fractures are sequella of a fall from a bicycle (22). Though most commonly seen in the pediatric population, ACL avulsion fracture does happen in adults (23); however, with older patients, tibial eminence fractures are often combined with lesions of menisci, capsule, or collateral ligament (24).

As with other fractures within the knee, patients with fractures involving the tibial eminence present with a painful swollen knee and usually cannot bear weight. The pain may make a thorough examination of ligaments impossible, but a complete neurologic and vascular examination must be obtained (3).