DOS 2017

· DOS Abstracts

Bearing dislocation in domed lateral Oxford Unicom-

partmental Knee replacement - short- to mid-term

follow-up of 45 knees

Thomas Lind-Hansen, Claus Varnum, Lasse Enkebølle Rasmussen

Ortopaedic Department, Vejle Hospital; Ortopaedic Department , Vejle Hospital;

Ortopaedic Department Vejle Hospital, Vejle Hospital

Background:

The indication for the domed lateral Oxford Unicompartmental

Knee Replacement (OUKR) is isolated lateral unicompartmental osteoarthritis.

Since the introduction of the implant, dislocation of the mobile bearing has been

a concern. Our series represents one of the largest independent series published

from non-design centres.

Purpose / Aim of Study:

To evaluate the outcome of the first 45 domed lat-

eral OUKR, operated at Vejle Hospital, regarding bearing dislocation and revision

in a retrospective cohort study.

Materials and Methods:

The files of all patients operated with the domed lat-

eral OUKR in our institution from February 2010 – June 2016 was reviewed re-

garding implant size, surgeon, revision of any cause, and latest available patient-

reported outcome. All patients had at least 1-year follow-up.

Findings / Results:

We identified 46 patients (48 knees: 27 females (1 bi-

lateral) and 19 males (1 bilateral)) operated by 6 different surgeons. 6 (13%)

bearings dislocated causing open revision with replacement of the bearing. Me-

dian time to dislocation was 103 days (range 47-469 days),only one bearing

dislocated after one year. 3 (7%) knees were revised to total knee replace-

ment (TKR) due to progression of osteoarthrosis (n=1) and following disloca-

tion (n=2). Of the remaining 45 domed lateral OUKR, 41 (91%) reported that

they were satisfied or very satisfied at the one year follow-up.

Conclusions:

The domed lateral OUKR is a challenging procedure with concern-

ing rates of dislocation, which was also found in this series. However, it seems

that good or excellent performance can be achieved despite early dislocation.

But it is concering that 2/6 knees with dislocated bearing had to be revised to

TKR, further emphasizing the challenges with the procedure in regards of dis-

location.

No conflicts of interest reported

10.