Keywords
adolescent - child - elbow joint - heterotopic ossification - joint dislocations
Introduction
The elbow is the most common major joint to present traumatic dislocation in childhood,
although the lesion is relatively rare, representing from 3% to 25% of all pediatric
elbow injuries.[1] Pediatric elbow dislocations are complex lesions, associated with fractures in 75%
of cases, while simple dislocations (purely ligamentous) in children are associated
with a varying degree of soft-tissue injuries.[1]
[2]
Following elbow dislocation, patients might present a varying loss of range of motion
(ROM) associated or not with heterotopic ossification (HO),[3] which is the development of mature lamellar bone within tissues beyond the periosteum,
such as skeletal muscle, fibrous and capsuloligamentar components, and subcutaneous
tissue.[4] In most cases, HO is asymptomatic and detected as an incidental imaging finding.
However, it might be painful and associated with focal dysesthesia, signs of inflammation,
and decreased ROM. Symptomatic HO around the elbow in children is an uncommon finding,
especially without an associated fracture or history of surgery.[4]
[5] Here, we describe a case of an 11-year-old girl with HO following a traumatic elbow
dislocation without associated fractures, but with partial disruption of the brachialis
muscle. During the follow-up, the patient experienced persistent loss of flexion,
and underwent surgical excision of the HO, followed by normalization of elbow motion
and no recurrence.
Case Report
The present study was approved by the Institutional Review Board (under protocol n°
36203120.6.0000.0023), with signed consent from the participant and her parents.
An 11-year-old girl was admitted to the emergency room reporting a fall from a small
height and indirect trauma to the left elbow. There was no history of musculoskeletal
lesion on the affected upper arm. During the physical exam, she presented severe pain,
swelling, tenderness, and elbow deformity without neurovascular deficit. The radiographs
showed posterolateral dislocation of the elbow without concomitant fractures. A closed
reduction under anesthesia was performed, and the elbow was immobilized with an above-elbow
plaster splint in 90° of flexion and neutral rotation for one week, followed by two
weeks of a shoulder sling. However, because of important elbow edema and ecchymosis,
a magnetic resonance imaging (MRI) scan was performed, showing partial rupture of
the fibers of the brachialis muscle, and a poorly-defined blood collection ([Fig. 1]). No specific treatment was performed to address the brachialis muscle lesion. After
six months of physical therapy, the patient had a pain-free ROM of ∼ 90° (flexion
of 95° and extension deficit of 5°). No loss of pronation or supination was noticed.
A sizable solid mass was palpable anteriorly at the distal extremity of the humerus.
Radiographs and computed tomography (CT) scans showed HO at the anterior aspect of
the distal humerus causing potential joint impingement ([Fig. 2]). Because of the residual loss of ROM, the decision was to resect the HO surgically.
Fig. 1 (A) Lateral and (B) anteroposterior (AP) radiographs of an 11-year-old girl showing posterolateral dislocation
of the elbow without concomitant fractures; lateral (C) and (D) AP radiographs after closed reduction, showing congruent joint without fractures.
(E) Magnetic resonance imaging (MRI): T2-weighted sagittal scan of the left elbow following
the traumatic elbow dislocation after closed reduction. The MRI shows partial rupture
of the fibers of the brachialis muscle, and a poorly-defined blood collection of 3.1 cm × 1.8 cm.
Fig. 2 Lateral radiograph (A) and sagittal (B), axial (C), and 3D (D) computed tomography (CT) scans of the elbow showi g heterotopic ossification (HO)
at the anterior aspect of the distal humerus causing potential joint impingement.
The patient was submitted to general anesthesia and brachial plexus block. A direct
lateral approach was performed, followed by excision of the HO by means of osteotomy
and osteoplasty ([Fig. 3]). A complete ROM was achieved. The day after surgery, she was advised to perform
active and passive kinesiotherapy, progressing to physical rehabilitation after seven
days. No additional prophylaxis for HO was administered. At 12 months postoperatively,
the patient had pain-free symmetric ROM, with no residual instability, preserved strength,
and radiographs with no evidence of recurrence of the HO ([Figs. 4] and [5]).
Fig. 3 Intraoperative photograph showing HO of the distal humerus through the direct lateral
approach (A). Intraoperative lateral X-ray of the elbow after excision of the HO (B).
Fig. 4 At 12 months postoperatively, the patient had symmetric range of motion, with no
residual instability.
Fig. 5 Lateral (A) and AP (B) radiographs of the elbow 12 months after surgery, showing no evidence of recurrence
of HO.
Discussion
Dislocation of the elbow joint is an uncommon injury in younger children, who usually
experience elbow dislocation in association with fractures, particularly of the medial
epicondyle, proximal radius, and coronoid process.[1]
[2]
[3] Pediatric elbow dislocations with no concomitant fractures are rare, with few cases
reported in the literature.[1]
[3]
[6]
[7]
[8] The complications of elbow dislocation are mostly related to neurologic (10%) and
vascular injuries (6% to 8%), HO and loss of motion, recurrent dislocations, radioulnar
synostosis, and cubitus recurvatum.[1]
[6]
[7]
[8]
[9]
Posttraumatic insult is the most common cause of HO, typically following fractures,
dislocations, and operative procedures, accounting for up to 75% of the cases.[5]
[7]
[9] However, it is uncommonly symptomatic, especially in the pediatric age group.[5]
[6]
[8]
[9] In this scenario, the damage to the brachialis muscle fibers and the formation of
a focal hematoma may predispose to the development of the HO.[5]
[9] Furthermore, a recent study[5] suggested that overweight and obesity in pediatric patients may be a risk factor
for HO. In the case herein presented, the child was overweight, a factor that may
have contributed to the occurrence of HO.
Susnjar et al.[8] reported a case of a 9-year-old girl with formation of HO at the elbow after the
surgical treatment of a fracture of the lateral humeral condyle. The HO was surgically
removed eight months after the first surgery. Araoojis et al.[6] reported a unique case of complete medial elbow dislocation in a 10-year-old boy
who underwent closed reduction under general anesthesia. After 2 years of follow-up,
the radiograph showed matured HO along the anterior capsule, but the patient had full
elbow ROM, and did not require surgery.
In the literature, the prophylaxis and drug prevention for HO are controversial. Drug
prophylaxis with indomethacin and other nonsteroidal anti-inflammatory drugs have
been advocated in the early stages and after surgical excision.[4] In contrast, indomethacin has been reported as a non-effective prophylaxis for HO
after surgery for acetabular fractures.[10] Radiotherapy has also been suggested as effective to prevent HO if performed 24 hours
preoperatively or up to 72 hours postoperatively.[4] Nevertheless, evidence for the prophylaxis with indomethacin or irradiation to prevent
posttraumatic HO is lacking for the pediatric population.[1]
[6]
[8]
We described a unique case of a child who sustained a complete elbow dislocation and
partial disruption of the brachialis muscle, evolving with HO and loss of ROM. The
patient underwent surgical treatment and resection of the HO with an excellent result,
with no recurrence. We recommend the maturation of the HO to program a surgical treatment,
and we did not administer prophylaxis for HO beyond early kinesiotherapy.
