In unicompartmental knee arthroplasty (UKA), extension gap commonly decreases after inserting the trial components. As most of UKA technique incorporates the fixture of implants using bone cement, it is likely that the gap decreases further when inserting the actual implants. We performed a new additional procedure that enables a precise adjustment of the extension gap. Thirty-two patients who had undergone UKA (ZIMMER Unicompartmental High-Flex Knee System, Zimmer®, Warsaw) using the spacer block technique at our hospital in 2013 were reviewed. Ten cases had difficulties in achieving full extension after the trial implants were inserted, and hence, a new procedure of longitudinal incision between the medial collateral ligament and the posterior capsule was performed. This additional method created a mean increase of 3mm of the extension gap, and facilitated the knee to extend completely. There were no cases that had an increase in the flexion gap. Previously, a tibial osteotomy was added in such cases, but this had a risk of increasing not just the extension gap but also the flexion gap. This method is a valid technique for precise adjustments, and could also be applied to patients with severe flexion contracture to treat by UKA.
Multimodal local periarticular injection can be effective for pain management after total knee arthroplasty. We have investigated to get the similar results after total hip arthropasty. Sixty patients undergoing total hip arthroplasy were divided to two groups. One were with multimodal local periarticular injection(Group M) and the other were with single intraarticular injection Group C, conventional method. We injected a “cocktail” agents into the soft tissue (capsule, synovium, muscle, subcutaneous fat tissue, skin) around the implants. Those were contained Morphinesulfate, Ropivacaine, Adrenaline, Methylpredonisolone, Ketoprofen, and Normal saline. We compared the VAS(at rest and during walking), the duration of the mobilization and active SLR, and any complicaions.Objection
Methods
As an essential concept in TKA, preparing equalized rectangular extension and flexion gaps is recognized as desirable to ensure proper knee kinematics. However, in the ways that was recommended by an implant manufacturer, the adjustments are so difficult, and for inexperienced doctor, we don't have an ideal technique for an additional cutting up and ligament balancing. Then, the New method (Precut method) was introduced in order to enable an ideal adjustments. Sixty eights patients with osteoarthritis of the knee received TKAs using Precut method. This method is the following. At first, proximal tibia was resected 10 mm by standard cutting device. And then, femoral posterior condyle was resected 4 mm lesser than cutting line by measured resection technique (Precut method). In the next, using the spacer block 1 mm unit and the Precut trial implant (8 mm; distal femur 4 mm; posterior condyle), we investigated the bone gap and the component gap (put the Precut trial on the distal femur). Finally, we calculated the amount of the final cutting value based on the component gap. The survey item measured the bone gap at extension and flexion, the component gap at extension and flexion after putting the Precut trial on. Then we compared the gap difference with and without the Precut trial.[Introduction]
[Method]
