| disease | Tibia Condyles Fracture |
Tibial condyle fractures account for approximately 0.38% of all fractures in the body and are relatively common. They predominantly occur in young adults, with a higher incidence in males than females. Tibial condyle fractures are more frequently seen than medial hip fractures. As intra-articular fractures, they involve the proximal tibial articular surface. In severe cases, they may also be accompanied by meniscus and ligament injuries. Consequently, tibial condyle fractures can easily lead to functional impairment of the knee joint. To achieve the best possible functional recovery, treatment should vary depending on the severity of the injury, the type of fracture, and the presence of associated injuries.
bubble_chart Pathogenesis
The upper ends of the adult tibia on both sides consist of cancellous bone, and the area below the lateral edge lacks strong support, making it a weak point prone to fracture. Both direct and indirect forces can cause tibial condylar fractures. Direct forces are commonly caused by impacts from car bumpers. Indirect forces often result from falls from heights where both feet land, compressing the tibial condyles. Alternatively, varus or valgus stress can lead to fractures combined with knee ligament injuries. Since the medial side is protected by the contralateral lower limb, varus stress is less likely to occur, making lateral condylar fractures more common than medial ones.
Vertical compressive forces often cause T-shaped or Y-shaped bicondylar fractures. Rotational stress can also lead to tibial condylar fractures, which may be accompanied by ligament injuries.
When the injury occurs with the knee in extension, it often results in a single condylar fracture, whereas injuries in flexion typically cause fractures limited to the middle or posterior part of the tibial condyle. Valgus stress with the knee flexed and the lower leg externally rotated can cause a fracture of the anterior part of the lateral tibial condyle. Conversely, varus stress with internal rotation can lead to a fracture of the anterior part of the medial condyle.
1. Due to variations in the direction, magnitude, duration of the force, and the patient's posture at the time of injury, there are many classification methods for tibial condylar fractures. The commonly used methods are as follows:⑴ Single condylar fracture: Mostly caused by pure external bone stress. It is further divided into split-type and depressed-type. The former involves a fracture line separating one condyle, while the latter mainly involves trabecular bone fracture with articular surface depression. Valgus injuries are more common, with mild cases causing medial collateral ligament injuries and severe cases leading to lateral tibial condylar fractures. Sometimes, these are accompanied by fractures of the upper fibula or common peroneal nerve injuries.
⑵ Bicondylar fracture: Often caused by vertical compressive force. If combined with valgus stress, one side may be more severely injured. Vertical compression fractures may involve more severe bone damage but often do not involve ligament injuries. The prognosis after reduction is relatively good.
⑶ Tibial plateau compression and comminuted fractures: These are the most severe among tibial condylar fractures.
2. Beijing Jishuitan Hospital classifies tibial condylar fractures based on the mechanism of injury and severity as follows:
⑴ Valgus type: Caused by valgus stress, the most common type, accounting for about 70% of such fractures. It is further divided into four degrees based on injury severity.
Ⅰ degree: Non-displaced or grade I displaced split or compression fracture of the lateral tibial condyle, with articular surface depression not exceeding 0.5 cm.
Ⅲ degree: Bicondylar fracture, with the lateral condylar fracture similar to degree II but with compression exceeding 1 cm. Often comminuted, even extending to the intercondylar eminence. The tibial condyle widens beyond its normal width, but the articular surface remains intact. The medial condylar fracture line runs obliquely upward and outward through the lateral condylar compression fracture.
Ⅳ degree: Compression of the medial two-thirds of the lateral tibial condyle, similar to degree III, with the medial condylar articular surface intact. An oblique fracture extends from the lateral condylar compression fracture to below the medial condyle, with significant shortening displacement. The lateral one-third of the lateral tibial condyle remains continuous with the tibia (possibly with a fissure fracture) and shifts proximally to the lateral side of the lateral femoral condyle, appearing dislocated, resulting in varus and internal rotation deformity.
⑵ Varus type: Caused by varus stress, accounting for about 18.2% of such fractures. It involves compression or split fractures of the medial tibial condyle, usually without severe displacement. Injuries near knee extension present as fractures of the entire medial condyle. Injuries in knee flexion present as split fractures of the posterior half of the medial tibial condyle. If the injury occurs with the knee flexed and the lower leg internally rotated, it manifests as a fracture of the anterior half of the medial condyle.
bubble_chart Clinical Manifestations
There is a history of severe trauma to the knee joint. After the injury, knee pain and tenderness occur, accompanied by functional impairment. Not only is the affected lower leg unable to bear weight, but it also cannot actively extend or flex. In severe cases, there may be varying degrees of intra-articular hemorrhage, along with widespread or localized swelling. Additionally, varying degrees of deformity may occur. A fracture of the external hip bone can result in a genu valgum deformity. In cases of comminuted fracture, bone crepitus may be palpable. Swelling and tenderness at the collateral ligament site indicate a collateral ligament injury, and an anterior-posterior drawer test should be performed to rule out a cruciate ligament injury.
If a fracture of the upper tibia is suspected, it is essential to take anteroposterior and lateral X-rays to assess the extent and characteristics of the fracture. It is also important to obtain oblique views to visualize the posterior contour of the affected tibial condyle.
bubble_chart Treatment Measures
1. In order to maximize the recovery of knee function and avoid joint instability, deformity, stiffness, and pain, appropriate treatment methods should be adopted based on the original fracture condition of the upper tibia. Two principles should be noted:
(1) Early mobilization can prevent movement disorders and pain caused by intra-articular adhesions and better reshape the damaged joint surface. Joint movement should begin as early as possible; the more severe the injury, the more necessary early joint mobilization becomes.
(2) Accurate reduction and maintaining the position of fracture reduction can prevent joint instability and deformity. However, anatomical reduction is not strictly required. Traction is a preferable method to both maintain the reduction position and enable early mobilization.
2. The treatment methods include the following:
(1) Plaster cast fixation is suitable for non-displaced or grade I displaced split fractures, or compression fractures not exceeding 1 cm. For grade I and II valgus injuries, minimally displaced varus injuries, and vertical injuries, plaster cast fixation should be applied for 3–4 weeks, with early initiation of quadriceps exercises. Sometimes, for grade III and IV valgus injuries, manual or leverage reduction can be performed first, followed by plaster cast fixation to maintain the reduced position. After 4–6 weeks of plaster cast fixation and initial healing, the cast can be removed for knee joint functional exercises, but weight-bearing walking should not begin earlier than 8 weeks.
(2) Traction therapy is a commonly used and effective method for upper tibial fractures. For significant displacement in varus, valgus, or vertical injuries, lower tibial or transcalcaneal traction is preferable. The affected limb should be placed on a Thomas splint, with the lower leg positioned on a Pearson attachment. The junction point of the Pearson attachment and the Thomas splint should align with the flexion-extension axis of the knee joint, allowing flexion-extension exercises. Additionally, depending on the fracture characteristics, the lower leg can be positioned in varus or valgus using the attachment. Once initial fracture union is achieved, sliding traction can be converted to fixed traction to expand the range of knee joint functional exercises. Traction can be discontinued after 6 weeks, but weight-bearing should only begin after solid fracture healing to avoid deformity.
This method of traction combined with early mobilization allows the remodeling of the tibial condyle shape during fracture healing. Post-healing joint imaging, surgical exploration, or arthroscopic observation reveals that even severely comminuted fractures can result in surprisingly smooth joint surfaces after remodeling.
(3) Surgical treatment: For single or double condylar fractures, bone bolts can be used for internal fixation. For smaller split fractures, cancellous bone screws can be employed. For comminuted multi-fragment fractures, multiple screws in different directions can be used for internal fixation. For compression fractures, leverage reduction can be performed, with cancellous bone or bone cement filling the bone defect. In cases involving ligament injuries, the ligament should be repaired according to the injury condition in addition to fracture treatment.
For tibial condylar fractures, clinical practice at Beijing Jishuitan Hospital shows that the excellent rate of conservative treatment can reach 77%, while the excellent rate of surgical treatment is only 45%. This indicates that non-surgical treatment combined with early functional exercise remains the primary method for tibial condylar fractures. With proper application, a high excellent rate can be achieved.
However, surgical treatment still has its indications as a therapeutic method and should not be entirely dismissed.
