A Case of Nonunion with Ballooning Deformity after Periprosthetic Humeral Fracture

Abstract

Introduction: We report a very rare case of nonunion with ballooning deformity of the humeral bone after a periprosthetic humeral fracture nonunion.

Case report: A 79-year-old woman underwent hemiarthroplasty 19 years ago for her proximal humerus fracture. She injured her right humeral diaphysis (stem distal end fracture) 6 years ago. She underwent revision hemiarthroplasty with long stem, but bony union was not obtained, and her right upper limb function was subsequently abolished due to extreme instability and pain in her right upper arm. She was then referred to our hospital for further treatment. X-ray showed nonunion in the humeral diaphysis and a severe ballooning deformity in the distal humeral bone fragment. Due to the advanced age and low activity of the patient, we chose total humerus replacement surgery instead of osteosynthesis. After the surgery, her upper arm pain and instability immediately improved. Three years after the last surgery, there have been no implant failures, and the upper arm is stable and painless.

Conclusion: Although there are some reports of total humerus replacement as surgical treatment for humeral tumor and severe periprosthetic fracture, we found no reports of such ballooning deformity around the nonunion site. Total humerus replacement can be one of the treatment options in cases where nonunion surgery is extremely difficult, depending on the patient's age and activities of daily living.

Keywords: Ballooning deformity; nonunion; periprosthetic fracture; total humeral replacement.

Figure 1

(a) Plain radiograph at the first visit to our hospital. Severe ballooning deformity is observed in the humeral bone beyond the nonunion site. (b) A flask-like deformation is observed on 3D computed tomography.

Figure 2

(a) Plain radiograph after a periprosthetic fracture. Fracture is found at the tip of the stem. (b) Plain radiograph after a revision hemiarthroplasty with a long stem. The reduction and fixation of the fractured site is insufficient. (c) Plain radiograph 3 months after the revision surgery. Aseptic loosening is observed at the tip of the stem. (d) Plain radiograph 1.5 years after the revision. A small ballooning deformity is recognized around the tip of the stem.

Figure 3

(a) AP view of a plain radiograph after total humeral replacement. AP: anterior posterior. (b) Lateral view of a plain radiograph after total humeral replacement.

Figure 4

Photograph of the nonunion part and the ballooning deformed part. Vertically divided photograph of the ballooning deformity.

Figure 5

Photograph of the final examination. Active shoulder joint movement is almost impossible, but elbow joint function is maintained.