The medial pivot concept was introduced in Europe in 1998. All data of more than 2000 Advance Medial Pivot knee cases (2 surgeons) were performed and recorded in a prospective way. No revision for wear or loosening related to wear was observed in these 15 years. In May 2012 the next version was introduced in Europe and we were the first department to use the Evolution Medial Pivot Knee system. The basic concept was not changed but some adaptations were realised according to the experience gathered with its predecessor. Extra sizes, asymmetric implants and size interchangeability allowed us to fine-tune this very successful implant in combination with a fast track protocol.
From May 2012 to April 2014 the first 200 consecutive cases (single surgeon) were recorded prospectively. Age at operation ranges from 37y to 94y and the BMI is on average 28,7. 98% were primary cases with 20% of valgus knees. Revision of a failed unicompartmental implant was performed in 4 cases. The fast track protocol includes the use of a single shot of a long acting local anaesthetic with immediate mobilisation and no use of epidural pain pumps. Discharge home is routinely done the third postoperative day. All patients were evaluated at 2m, 6m, 1y and 2y postoperatively with recording ROM, stability and PROM’s including KOOS and patient satisfaction. Xray were obtained at day 3, 2m, 1y and 2y.
All patients are available for follow up. There were no postoperative complications except for 4 DVTs. The mean ROM is 123°. The PCL is cut in all cases. No extra releases were done in 77%, IT releases in 23%, LCL release in 2,5%, popliteus in 4%, patellofemoral releases in 10%. 31% benefits from size interchangeability. 41% were very satisfied, 48% satisfied, 5% reported OK and 0,5% (1 patient) was not satisfied. The remaining 10 patients were operated very recently and wanted to wait before answering the satisfaction score. The Net Promotor Score was 99,5%. The KOOS score at 1y: Pain 88, Symptoms 82, ADL 89, Sports 69, QoL 79. 20% did not respond to the Sports questionnaire.
The success of TKA surgery depends on many factors including patient, surgery and implant variables. Choosing the correct size and the optimal individual ligament balance during surgery are the major determinants for an excellent result. In the author’s experience, patients have expressed a feeling of stability that has allowed them to return to activities such as stair descent and hiking on rough surfaces, and even sports including tennis and jogging. Long term data (>15y) are very promising and allow us to use this implant also in the younger patient provided the indication is correct.