Intramedullary nailing using K-wires for high-energy distal humeral metaphyseal-diaphyseal fractures accompanying radial nerve palsy in a 2-year-old toddler: A case report

Abstract

Rationale: Pediatric distal humeral diaphyseal fractures are rare and challenging to manage due to anatomical and biomechanical complexities. In addition, humeral shaft fractures in adults are often accompanied by radial nerve paralysis (RNP), but there are no studies on the incidence or treatment of pediatric humeral shaft fractures accompanied by RNP in toddlers. The authors present the outcomes of closed reduction and intramedullary nailing using Kirschner wires (K-wires) for high-energy distal humeral metaphyseal-diaphyseal open fractures accompanied by RNP in a toddler. This case report aims to highlight an effective surgical approach and its outcomes in a toddler, providing insights for clinicians facing similar scenarios.

Patient concerns: A 23-month-old boy was referred to our emergency room after several hospital visits. He complained of pain in his right arm and presented wrist drop due to a crushing injury by a conveyor belt. A 1 cm open wound was located at the lateral side of the elbow.

Diagnosis: The patient was diagnosed with an open displaced fracture in the distal third of the right humerus on radiographic examination and RNP was diagnosed on the basis of physical examination.

Interventions: The authors initially attempted open reduction and internal fixation of the fracture using a Steinmann pin after radial nerve exploration, which confirmed continuity of the normal radial nerve, but fixation failed. Reduction loss and displacement progressed with pin migration the day after surgery, and revision surgery was selected. Closed reduction and intramedullary nailing using K-wires were performed on day 2 after the primary surgery.

Outcomes: The patient recovered his ability to extend the wrist and metacarpophalangeal joint approximately 3 weeks after surgery. At the 1-month and 6-month follow-up, the fracture had healed, and radial nerve function had recovered completely.

Lessons: Intramedullary nailing using K-wires for metaphyseal-diaphyseal fractures of the humerus in toddlers is an effective operative treatment. Among them, high-energy open fractures accompanied by radial nerve palsy might require nerve exploration.

Keywords: distal humeral metaphyseal–diaphyseal fracture; high-energy injury; intramedullary nailing; pediatric open humeral fracture; radial nerve palsy; toddler.

Figure 1.

Anteroposterior view of the right humerus showing a severely displaced metaphyseal–diaphyseal fracture of the distal humerus.

Figure 2.

Computed tomography scans of the right humerus revealing a severely displaced metaphyseal–diaphyseal fracture of the distal humerus.

Figure 3.

(A) The radial nerve was entrapped between fragments, and it had edema and contusion, but contained normal continuity. (B) The fracture was reduced and fixed with 2.0 mm Steinmann pins. (C) The reduction and fixation status was checked using fluoroscopy (*: radial nerve; white triangle: reduced fragments).

Figure 4.

(A) Reduction loss was identified on immediate postoperative radiographs. (B) Increased reduction loss and migration of Steinmann pins were confirmed on radiographs taken the day after the first surgery.

Figure 5.

(A) Acceptable reduction was achieved via intramedullary nailing using Kirschner wires according to fluoroscopic images. (B) Postoperative radiographs of the second surgery. (C) Radiographs at 1 year and 6 months after the 2nd surgery.