Orthonotes
Orthonotes
by the.bonestories
v3.0 Fusion
v3.0 Fusion
arthroplasty topic hub

Modular Taper Junctions & Trunnionosis

Trunnionosis = corrosion/wear at head–neck modular junction of THA. Mechanism: fretting + crevice corrosion, leading to metal ion release. Clinical: unexplained pain, swelling, adverse local tissue reaction (ALTR). Diagnosis: ESR/CRP to rule out infection; elevated cobalt/chromium; MRI (MARS) for pseudotumor. Management: revision with ceramic heads, titanium sleeves; avoid further corrosion.

Overview

Topic summary

View wiki
Trunnionosis = corrosion/wear at head–neck modular junction of THA. Mechanism: fretting + crevice corrosion, leading to metal ion release. Clinical: unexplained pain, swelling, adverse local tissue reaction (ALTR). Diagnosis: ESR/CRP to rule out infection; elevated cobalt/chromium; MRI (MARS) for pseudotumor. Management: revision with ceramic heads, titanium sleeves; avoid further corrosion.
MCQs

High-yield practice questions

Start topic quiz
Question 1

Which ion is predominantly released in cases of trunnion corrosion involving a cobalt-chromium head?

Question 2

A patient presents with new-onset hip pain and a palpable mass months after THA with a CoCr head. Which diagnostic test is most appropriate to assess for trunnionosis?

Question 3

What is a common clinical feature of adverse local tissue reaction (ALTR) due to trunnionosis?

Question 4

Which of the following factors is NOT associated with an increased risk of trunnionosis?

Question 5

In patients with suspected trunnionosis, what is the significance of measuring serum cobalt and chromium levels?

Question 6

What adverse tissue reaction is commonly associated with elevated cobalt levels in patients with trunnionosis?

Question 7

What is the recommended management for a patient diagnosed with trunnionosis?

Question 8

Which of the following is NOT a distinguishing feature of trunnionosis compared to metal-on-metal (MoM) bearing wear?

Question 9

What is a key characteristic of the modular taper junction in total hip arthroplasty?

Question 10

What is the primary mechanism involved in trunnionosis at the head–neck junction of a total hip arthroplasty (THA)?