Orthopedic Teaching Cases 2023, Jan, 20 | 12:00 am

CASE 44 tibial plateau fractures

A 37-year-old male presents to the emergency department after a fall from 20 ft. Figure 6–46 depicts an AP radiograph of the patient’s right knee. The skin about the knee is intact, however, there is significant ecchymosis and evolving hemorrhagic blisters noted medially. ABI measures 1.1 and this appears to be an isolated injury.

 

 

 

Figure 6–46

 

Based upon the description of the patient’s knee, what is the most appropriate next step in the management of this injury?

  1. Closed reduction and application of a long leg cast in 30 degrees of knee flexion

  2. Open reduction internal fixation using a lateral buttress plate and raft screws

  3. Open reduction internal fixation using a lateral buttress plate and a separate posteromedial plate

  4. Application of a knee-spanning external fixator

 

Discussion

The correct answer is (D). The vignette describes a bicondylar tibial plateau fracture with extensive injury to the surrounding soft tissues. Egol et al. describe their success in treating high-energy proximal tibia fractures in temporizing knee-spanning external fixators, citing low infection rates, improved soft tissue access, and the mitigation of articular damage.

Regarding the surgical tactic used to address bicondylar tibial plateau fractures, which of the following statements is true?

  1. Plating of both lateral and posteromedial fracture fragments can reliably be approached through one midline incision.

  2. Coronal splits of the posterior aspect of the medial condyle can be stabilized by appropriately oriented lag screws that allow compression across fragments.

  3. Heterotopic ossification is a frequent complication of high-energy tibial plateau fractures.

  4. Posteromedial intra-articular fragments not properly stabilized tend to collapse into varus.

Discussion

The correct answer is (D). Posteromedial fragments tend to collapse into varus even with newer locking plate technology. When applying lateral and posteromedial plates, a two-incision approach significantly reduces the risk of nonunion and infection. If posteromedial coronal split fragments are to be addressed by laterally placed screws, a locked construct has been shown to be biomechanically superior to lag screws. Heterotopic ossification is an infrequent complication of high-energy tibial plateau fractures. The exception to this generalization being in the setting of a fracture-knee dislocation, which is more likely to be complicated by heterotopic ossification formation.

All of the following are true regarding complications and outcomes related to

high-energy tibial plateau fractures EXCEPT:

  1. Those fractures treated definitively with external fixators exhibit acceptable clinical outcomes in terms of range of motion when compared to the contralateral extremity.

  2. The degree of residual articular step-off is a major determinant of the development of post-traumatic arthritis.

  3. Extra-articular malunions are more common than intra-articular malunions.

  4. The rate of septic arthritis related to external fixator placement can be mitigated by placing pins and wires at least 14 mm below the joint.

Discussion

The correct answer is (B). The degree of residual articular step-off has not reliably been shown to predict the development of post-traumatic arthritis. Weigel and Marsh demonstrated that patients treated definitively with a uniplanar external fixator have good prognosis with satisfactory knee function at 2- and 5-year follow-up. Nonunion typically occurs in the proximal tibial metaphysis. Reid et al. defined the “safe zone” for the placement of periarticular pins through a cadaver model showing the maximum distance between the reflected joint capsule and subchondral bone to be 13 mm.

 

Objectives: Did you learn...?

 

Understand the advisability of a staged surgical approach to high-energy tibial plateau fractures?

 

The surgical tactic is dependent upon the nature of the fracture. In general, better outcomes have been reported with a two-plate construct when addressing a posteromedial coronal split fragment?

 

Outcomes of operatively treated tibial plateau fractures are often dictated by the restoration of the joint axis rather than the amount of residual articular incongruity?