Samuel Morganabout 4 years ago
Faithful readers, welcome back.
This week we briefly review the recent ANZ Journal of Surgery article by Xu et al about Unicompartmental Knee Arthroplasty (UKA).
The team behind the article set out to evaluate the mid-term results of an Oxford phase-3 UKA on a Chinese population with medial arthritis.
They found improvements in:
- Knee range of motion
- Knee (clinical + functional) society scores
- Hospital society scores
With a high survival rate (at eight years = 93%) and relatively low revision rate at 10 years (~10%).
When you add this to a list a relative pros:
- shorter hospital stay
- better proprioception outcome
- maintenance of 'normal' knee dynamics and higher levels of activity due to retention of the ACL
What's the problem?
What about revision? Eventual involvement of the ipsilateral tibial surface? Expense to the patient, the healthcare system... Is the short lived, transient increase in function the right economic decision?
The study also admits the possible bias in follow up to due to imaging costs and poor contact with the patients by the maximum 10 year period. One referenced study showed the primary needs for revision being the lateral compartment, while another raised to issue of patello-femoral arthritis as the primary.
In addition to the small study size and need for randomisation, the poor outcomes were heavily related to surgical technique, another finding consistent with the literature.
The UKA serves a purpose, however, the clinical decision rests, as always, with a detailed history and examination and your clinical experience.
Xu T el at. Mid-term results of Oxford phase-3 medial Unicompartmental Knee Arthroplasty for medial arthritis in Chinese patients. ANZ Journal of Surgery. 2017;87(4);287-90.