Proximal tibia replacement with LINK Endo-Model SL for a traumatic tibial head impression fracture and unstable valgus defect gonarthrosis

Case Report: directLINK 1/2020

An 81-year-old female patient who fell down a staircase suffered a multiple fragment tibial head fracture with destruction of the lateral tibial plateau on the left. After closed reduction and the application of an external joint-bridging fixator for one week, the lateral tibial plateau was openly reduced, lined with 1/2 femoral head and 2.5cc bone substitute material, and fixed using plate osteosynthesis. The X-rays showed the correct position of the implants with proper reduction of the main fragments. When the tibial head fracture was consolidated, the metal was removed in September 2018.

Later on, however, a post-traumatic, laterally accentuated gonarthrosis occurred with extensive defects of the lateral tibial head. An arthroplasty procedure was agreed with the patient due to movement restriction, which did not respond to therapy, and persistent pain symptoms. 

The LINK Endo-Model SL formed the basis of the custom-made prosthesis

Because of the extensive bone defects in the lateral tibial head, LINK was asked to fabricate an individual implant for the patient. The basis of the tibial head replacement was the LINK Endo-Model SL Knee Prosthesis, in which the ventral contour of the tibial component was machined away so that the patient's tibial tuberosity could be preserved in order to protect the extensor apparatus. In the meantime, the left knee joint was completely unstable; the patient therefore initially received an orthosis. 

The custom implant from customLINK was available after three weeks.
 

Based on the patient's CT data, customLINK produced the requested product within three weeks; the implantation took place in December 2018. Since LINK supplied a saw guide exclusively made for the special design, it was much easier to cut the tibia precisely to size, and maintaining the tibial tuberosity did not pose any problem. The postoperative period at the clinic was uneventful. 

The patient is almost pain-free and walks short distances without a walking aid.

During a check-up two weeks after surgery, the patient was almost pain-free and able to walk shorter distances without walking aids. Extension in the knee joint is complete, active and strong; flexion is possible up to 120 degrees and the patella is correctly adjusted in the femoropatellar groove. 

X-rays taken in September 2018: 15 months after open reduction of the lateral tibial plateau and relining with 1/2 femoral head and 2.5cc bone graft substitute as well as fixation with bilaterally angle-stable plate osteosynthesis (June 2017), the bony consolidation of the fracture (1, 2 AP; 3, 4 lateral views) is evident.

X-ray planning of the LINK Endo-Model SL with modified proximal tibial replacement and cemented modular stem from customLINK (1, 2); preoperative CT images (3, 4) show the bony consolidation of the lateral tibial head impression fracture with the sunken lateral tibial head plateau.

Modified tibial partial replacement with machined surface to preserve tibial tuberosity (1); postoperative X-rays (February 2019) show the correct position of the LINK Endo-Model SL with the proximal tibial partial replacement (2, 3) from customLINK.