The important findings in these two cases were that acute KD associated with OA could be managed by TKA, with good functional outcomes. These cases showed that TKA could be indicated for acute KD associated with OA. However, early TKA procedures could lead to a risk of arthrofibrosis and joint stiffness.
KD is mainly caused by traumas, congenital anomalies,11,12 secondary lesions13 and so on. Both patients developed disabilities due to serious KD and severe OA. In the two cases, knee instability and pain with limited ROM were observed. Because of severe degenerative changes in the knee in both cases, the advantages and disadvantages of ligament reconstruction or repairs and joint arthroplasty were discussed and communicated with the patients who chose to undergo TKA over ligament reconstruction or single repair. TKA was chosen for these two patients because of severe knee OA, which is already an indication for TKA. The advantages of TKA include satisfactory outcomes, minimal complications, rapid postoperative rehabilitation, and early joint motion.4,14,15
A few studies have reported TKA for the treatment of KD,3–6 although all of these studies only reported TKA as treatment for chronic multiligament knee injury. Jabalameli et al.5 reported TKA with a constrained hinged prosthesis for patients with CMKI, and recently, Goyal et al.3 reported that two patients with KD III injuries underwent TKA with PS prostheses because of progressive OA that developed after the ligament reconstruction procedures. These patients achieved improved functional ability and returned to their previous jobs. Our two patients also achieved significant improvements in their VAS, OKS, and WOMAC postoperatively, which is similar to the results obtained in the aforementioned studies. One-stage TKA can reduce complications and costs and allow for early mobility. Our procedure was finished within the tourniquet time, as ligament reconstruction and repair procedures, with no increased intraoperative bleeding or postoperative infusion. Therefore, we consider that TKA is a favourable treatment for KD associated with OA. However, there were better functional outcomes and higher satisfaction for the right knee than for the left knee in case 1, and the patient in case 2 sustained stiffness of the left knee. Acute TKA could be related to stiffness and arthrofibrosis.3 It may be more appropriate to perform TKA after soft tissue and bone marrow oedema has subsided.
There are some limitations in this case report. First, we initially considered the two cases to be ordinary cases, and few intraoperative images were collected. Second, this surgical procedure can only be performed by highly experienced and specialized surgeons using the knee arthroplasty technique. Third, TKA may only be indicated in some cases of KD with severe OA and for elderly patients.
In conclusion, TKA could be indicated for acute KD associated with OA. However, early TKA procedures could lead to a risk of arthrofibrosis and joint stiffness.