Abstract
We studied a series of Endo-Modell(r) rotating hinge knee replacements (RHKRs) to determine indications, implant survival and complication rates.
Case notes were audited for a consecutive series of 129 implants performed between 08/12/2002 and 30/01/2009.
Indication for use of RHKR was complex primary arthroplasty in 37.8% and revision in 62.2%.
For primary arthroplasty with hinge prosthesis, commonest indications were: collateral ligament insufficiency (44.4%); advanced RA (13.9%); supracondylar fracture (5.6%). Indications for revision RHK arthroplasty were: aseptic loosening (40.4%); ligamentous or soft tissue failure (14.0%); periprosthetic fracture (7%); infection (51%). Infection was proven in 21% with 54% of patients requiring a one stage and 46% two stage revision. For revision cases, 74% of primary prostheses were cruciate retaining PFC (Depuy) and in 5%, the primary was itself an Endo-Modell(r) RHKR.
Mean time from index to revision procedures was 6.7 years (range 1 year – 23 years).
Complications were: deep infection (6.1%) and non-fatal PE (1%). None developed clinically detectable DVT. Transfusion was required in 29 cases (for such cases, an average 3 units was given). 30-day mortality was 1%. For the revision cases, the average length of hospital admission was 11 days.
Mean duration of follow up was 45 months (with a minimum of 21 days and maximum of 92 months). During this time 2 RHKRs failed. A total of 7 patients died during the period from complications unrelated to their surgery. 31 cases were lost to follow up.
We conclude that in this series of Endo-Modell(r) rotating hinge knee arthroplasties, results are comparable with similar revision procedures. There was a low rate of prosthesis failure, DVT and PE.