Abstract
Background
Dual compartment knee replacement has been introduced to allow sparing of the cruciate ligaments and lateral compartment and preserve some biomechanics of knee function.
Aim
To study the early clinical and radiographic results of this new prosthesis.
Method
Patients who underwent dual compartmental knee arthroplasty performed by 2 surgeons over a period of one year were studied prospectively. All subjects in the study had advanced symptomatic osteoarthritis of the medial and patellofemoral joints but had an intact ACL and preserved lateral compartment. All patients received the Journey Deuce Dual Compartmental Knee System (Smith & Nephew, Inc, Memphis, Tenn) with Oxinium femoral component and modular tibial component. Follow-up with clinical evaluation, radiographs and Oxford knee scores were performed at 6 weeks, 6 months, 1 year, 2 years.
Results
Mean follow up was 18months (range 12-24months). There were 15 patients (6 males, 9 females) with a mean age of 53 years (range, 46-68 years). Twelve of the 15 patients had their patella resurfaced. The mean inpatient stay was 4.5 days (range 3-11 days). The mean time taken for surgery was 80 minutes (range 77-112 minutes).
Six of the 15 patients had poor results following surgery. Five out of six patients with poor results had tibial base plate loosening. This was confirmed either on plain x-rays, bone scan or at the time of revision surgery. Patients with tibial base plate loosening typically presented with persistent pain, particularly of the metaphyseal region when weightbearing and an effusion.
One revision was performed for patellofemoral pain and maltracking. In total, three patients have already been revised and three are awaiting revision surgery. Further procedures were required in 2 patients.
Conclusion
The Deuce dual compartmental knee replacement in its current design results in an unacceptably high rate of failure due to tibial base plate loosening. Some of these patients had good results in the early postoperative period which then deteriorated. Considering the high rates of failure we do not recommend this replacement with its current tibial plate design.
