Among pediatric elbow fractures, the medial epicondyle fracture has a unique characteristic: it can appear small, almost marginal, but this isn't always the case.
An X-ray often shows a bone fragment on the inner side of the elbow. Sometimes it's minimally displaced, other times significantly displaced. In some cases, the elbow was also dislocated and then reduced. In other cases, the child or adolescent participates in sports that heavily stress the elbow, such as gymnastics, throwing, climbing, or contact sports.
For this reason, the question "cast or surgery?" doesn't have an automatic answer. The literature itself acknowledges that there is no absolute consensus on the displacement threshold that necessitates intervention, especially in intermediate fractures [1,2]. The Royal Children's Hospital Melbourne guidelines, for example, indicate that between 5 and 15 mm, the decision also depends on age, dominant limb, and sports activity, not just the radiographic measurement.
Why the Medial Epicondyle Isn't Just "A Tiny Fragment"
The medial epicondyle is the bony prominence on the inner aspect of the elbow. In children and adolescents, it corresponds to an apophysis, meaning an area still undergoing skeletal maturation.
It is an important anchoring point for the forearm's flexor-pronator complex and for the medial ligamentous compartment of the elbow. In practical terms, this region contributes to the stability of the inner side of the elbow, especially when the joint is subjected to valgus stress.
This doesn't mean that all medial epicondyle fractures require surgery. That would be incorrect. Many heal well with conservative treatment. However, it's equally wrong to always dismiss them as "minor fractures," especially when they are associated with dislocation, instability, neurological symptoms, or high athletic demands.
The First Point to Clarify: Was the Elbow Dislocated?
Elbow dislocation changes the clinical significance of the fracture.
When the elbow dislocates, the medial epicondyle can avulse due to traction and, after reduction, can remain incarcerated within the joint. This situation must be recognized immediately: the elbow may appear to be "back in place," but the fragment may still be interposed between the articular surfaces.
Therefore, after reduction of an elbow dislocation, follow-up X-rays are not only to confirm that the joint is reduced. They also serve to verify that the medial epicondyle has not become trapped inside the elbow. The RCH guidelines clearly state that, in case of suspected intra-articular incarceration, urgent open reduction and internal fixation are necessary [2].
This is one of the cases where conservative treatment is not a good shortcut. If the fragment is inside the joint, the problem is mechanical.
The Ulnar Nerve Must Always Be Evaluated
The ulnar nerve runs posterior to the medial epicondyle. It is the nerve responsible for the classic "funny bone" sensation when the elbow is bumped.
After a medial epicondyle fracture, tingling in the fourth and fifth fingers, altered sensation, electric pain, reduced strength, or difficulty with fine hand movements should therefore be sought.
Ulnar nerve involvement is not an accessory detail: it is among the relative indications for open reduction and internal fixation, especially if the neurological picture is clear or progressive [2].
Millimeters Matter, But Don't Decide Alone
The measurement of displacement remains important. An undisplaced fracture, a 7 mm fracture, and an 18 mm fracture are not the same thing.
However, the problem is that measurement is not always reliable. Standard X-rays can underestimate the actual displacement of the medial epicondyle, especially when the fragment displaces anteriorly or antero-inferiorly. Souder and colleagues have shown that standard projections can underestimate displacement and that an axial view of the distal elbow can estimate it more accurately and reproducibly [3].
This is an important practical point: if the therapeutic decision is based solely on "millimeters," one must at least be certain that those millimeters are measured correctly.
But even when the measurement is correct, it's not enough. The same displacement can have a different meaning in a small, non-athletic child with a non-dominant limb, compared to an adolescent gymnast or a thrower who uses that very elbow as their dominant limb.
When Cast Treatment May Be Reasonable
Conservative treatment is a reasonable choice when the fracture is minimally displaced, the elbow is stable, there are no signs of intra-articular incarceration, no ulnar nerve symptoms, and the child's functional profile does not require particularly high medial stability.
In these cases, immobilization can yield good results. One should not pursue the "perfect X-ray" if it doesn't change the expected functional outcome.
However, one point needs clarification: radiographic non-union of the medial epicondyle can be observed after conservative treatment and is not always symptomatic. This doesn't mean ignoring it, but interpreting it in the clinical context: pain, instability, functional limitation, and return to sport matter more than the image alone.
When Surgery Should Be Seriously Considered Instead
There are situations where surgery enters the discussion much more decisively.
The first is fragment incarceration within the joint after dislocation: in this case, the indication is strong.
The second is ulnar nerve involvement.
The third is significant displacement, especially beyond 10-15 mm, even though the threshold is not universally accepted.
The fourth concerns the functional profile: adolescent, dominant limb, throwing sports, gymnastics, or activities with significant valgus stress. The RCH guidelines specifically include the dominant arm in throwing athletes or gymnasts among the relative indications for surgery [2].
This doesn't mean operating on all athletes. It means avoiding too simple a decision.
The Athlete's Dilemma: Beware of Automatic Decisions
In the athletic child, the decision is often more delicate.
On the one hand, surgery can better restore anatomy and reduce the risk of medial instability in selected patients. On the other hand, not all displaced fractures in an athlete automatically lead to a poor outcome if treated conservatively.
Some retrospective studies have reported good outcomes even in patients treated non-operatively, including cases with associated dislocation, while other works emphasize the higher probability of radiographic union after fixation [1,4,5]. The point is that many case series are retrospective, with different indication criteria and not always comparable populations. Therefore, the controversy remains open.
The correct question is not: "they play sports, so they need surgery?".
The correct question is: "does that type of sport, on that elbow, with that fracture and that degree of stability, require more precise anatomical restoration?".
What Is Truly Evaluated
For a medial epicondyle fracture, one starts with an X-ray, but should not stop at the report.
It is evaluated whether the trauma was isolated or if there was an elbow dislocation. It is checked that the fragment is visible in the expected location and not incarcerated in the joint. Ulnar nerve function is documented. Age, skeletal maturity, dominant limb, sport played, and activity level are considered.
The X-ray is then carefully read: standard projections, image quality, and the actual possibility of measuring displacement. In doubtful cases, especially if the therapeutic decision depends on a few millimeters, it may make sense to use dedicated projections or further investigations.
Elbow stability, when assessable, completes the picture. It is not always possible to test it well in the acute phase due to pain and swelling, but clinical suspicion should be integrated with the traumatic mechanism and imaging.
The Practical Message
A medial epicondyle fracture should neither be dramatized nor trivialized.
Many children can be treated with a cast and recover well. In other cases, however, surgery is not an excess, but a reasoned choice: incarcerated fragment, complex dislocation, ulnar nerve involvement, marked displacement, instability, or high athletic demands.
The problem is not having a one-size-fits-all millimeter threshold.
The problem is understanding which elbow you are dealing with.
Bibliography
[1] Kamath AF, Baldwin K, Horneff J, Hosalkar HS. Operative versus non-operative management of pediatric medial epicondyle fractures: a systematic review. Journal of Children’s Orthopaedics. 2009;3(5):345-357. PMID: 19685254. DOI: 10.1007/s11832-009-0192-7.
[2] Royal Children’s Hospital Melbourne. Clinical Practice Guidelines: Medial epicondyle fracture of the humerus – Emergency Department. The guidelines provide practical indications on incarceration, displacement, age, dominance, sport, and ulnar nerve.
[3] Souder CD, Farnsworth CL, McNeil NP, Bomar JD, Edmonds EW. The Distal Humerus Axial View: Assessment of Displacement in Medial Epicondyle Fractures. Journal of Pediatric Orthopaedics. 2015;35(5):449-454. PMID: 25171678. DOI: 10.1097/BPO.0000000000000306.
[4] Knapik DM, Fausett CL, Gilmore A, Liu RW. Outcomes of Nonoperative Pediatric Medial Humeral Epicondyle Fractures With and Without Associated Elbow Dislocation. Journal of Pediatric Orthopaedics. 2017;37(4):e224-e228. PMID: 27741036. DOI: 10.1097/BPO.0000000000000890.
[5] Axibal DP, Carry P, Skelton A, Mayer SW. No Difference in Return to Sport and Other Outcomes Between Operative and Nonoperative Treatment of Medial Epicondyle Fractures in Pediatric Upper-Extremity Athletes. Clinical Journal of Sport Medicine. 2020;30(6):e214-e218. PMID: 30277893. DOI: 10.1097/JSM.0000000000000666.
Disclaimer: content for general informational purposes only. It does not replace a medical evaluation.
