The hip-arthroplasty community currently feels that the advantages gained from head-neck modularity outweigh the risks, but JBJS Case Connector raises that risk-benefit question in an August 26, 2015 “Watch” article. Modular head-neck failures of total-hip prostheses are indeed rare complications, but the potentially catastrophic consequences and a seemingly increased incidence are raising concern among orthopaedists.
Prompted by a case report by Swann et al. in the August 26, 2015 JBJS Case Connector and a report by Arvinte et al. in the April 22, 2015 JBJS Case Connector, the Watch describes three patients who experienced a complete head-neck dissociation seven to fourteen years after primary arthroplasty with modular components. The Watch also includes relevant findings from elsewhere in the orthopaedic literature to help surgeons better understand and minimize the risks.
The trunnion troubles described in this Watch represent a unique opportunity for orthopaedists and industry to work together to conduct multicenter retrieval studies to better understand, and prevent, these rare but serious outcomes. In the meantime, the Watch ends with the following message: “Absent ‘official’ protocols for monitoring THA patients with new-generation modular head-neck junctions, it would behoove hip surgeons to inform patients about these rare events and to encourage them to report any postoperative abnormalities, even if the signs or symptoms are not painful.”