Medial Condyle and Medial Epicondyle Fractures

Nonunion, Cubitus Varus, and Instability

These three pathologies cannot be examined in isolation, as nonunion may lead to shortening of the medial column of the humerus, which then may lead to cubitus varus, pain, and instability. Nonunion alone has been reported to occur in 9% to 33% of patients. Cubitus varus has also been reported, although measurements were rarely recorded in the same studies. Despite this, most authors report good early outcomes with conservatively and operatively treated medial condyle fractures, with most patients asymptomatic at short-term follow-up despite a decrease in range of motion of the elbow.

However, these optimistic outcomes are limited by the lack of medium- and long-term follow-up of these patients. A few case reports discuss adolescents or young adults presenting years after injury with a medial condyle nonunion complaining of elbow pain, loss of motion, and cubitus varus, thus necessitating surgical treatment. This is similar to the conundrum of the “asymptomatic nonunion” of the medial epicondyle discussed in the previous section of this chapter. We do not know if most nonunions of the medial condyle are truly asymptomatic, if the injuries will declare themselves in older age, or what the outcomes of delayed management will ultimately be.

Avascular Necrosis

Although rare, avascular necrosis of the medial condyle has been reported in a few patients. The blood supply to the medial pediatric distal humerus comes primarily from the anterior and posterior ulnar anastomotic vessels originating from the brachial artery. Distally, Haraldsson in 1959 demonstrated two sources of intraosseous end vessels that supply the medial and lateral trochlea originating from the anastomotic network. The physis acts as a barrier to blood flow as it does elsewhere in the body. Long-term outcomes are otherwise unstudied.

High Index of Suspicion for Medial Swelling in Younger Child, Even in Absence of Obvious Fracture

A high index of suspicion is necessary to properly diagnose and treat fractures of the medial condyle. Many of these children are younger and may be uncooperative with examination. Medial swelling and ecchymosis may be the only focal physical examination finding, apart from generalized pain and intolerance for elbow motion. Plain radiographic studies may be read as normal, or only notable for medial soft tissue swelling or a fleck of bone along the medial column. They may even be mistaken for a medial epicondyle fracture ( Fig. 4.1 ).

Early Advanced Imaging

In the absence of clear radiographic findings, early advanced imaging with magnetic resonance imaging (MRI) is recommended. Although computed tomography (CT), ultrasound, or arthrography may also be used, MRI allows examination of both bone and cartilage without additional radiation exposure. CT is less useful for nonossified tissues and entails increased exposure to radiation. Ultrasound examination, while increasing in quality and popularity in orthopedic surgery, has not been studied in medial condyle fractures. We believe arthrography to be a useful adjunct once in the operating room, but MRI is preferable as the diagnostic modality.

Early Open Reduction and Internal Fixation

Nondisplaced fractures may be treated with above elbow cast immobilization for 4 to 6 weeks, with careful follow-up. Displaced medial condyle fractures, however, require early open reduction and pin fixation on displaced fractures. Most authors report utilizing a medial-based incision to evaluate the chondral or osteochondral fragment, attempting anatomic reduction at the joint surface, and performing pin fixation for stabilization. Zhou et al. advocate for open reduction and percutaneous pinning of even minimally displaced fractures, citing the concern for delayed displacement; however, that group did not compare their findings to a control group of solely cast-immobilized patients.