Abstract
Introduction
Although Total elbow arthroplasty (TEA) generally provides favorable clinical outcomes, its complications have been reported with high rate compared with other joints. Previously, we used the Bryan & Morrey approach in TEA, which included separating the triceps muscle subperiosteally from the olecranon; however, since 2008, in order to prevent skin trouble and deficiency of the triceps, we performed TEA by MISTEA method, which required no removal of the subcutaneous tissue in the region of the olecranon and no release or stripping of the triceps tendon.
Objectives
The purpose of this study was to examine the utility of the MISTEA method by evaluating and comparing muscle strength and complications by using both the Bryan & Morrey approach and MISTEA method.
Materials and Methods
The study was conducted on 23 elbows, on which elbow muscle strength could be measured postoperatively at more than 6 months after TEA. Thirteen elbows were operated on the Bryan & Morrey approach (BM group; mean age, 62.3 years; mean follow-up period, 27 months), and 10 elbows on the MISTEA method (MIS group; mean age, 67.6 years; mean follow-up period, 19.1 months). To determine the elbow extensor and flexor strengths, measurements were conducted on the affected side for the BM group, and on both the affected and healthy sides for the MIS group. Further, the “extension/flexion ratio” as well as the “affected/healthy side ratio” and complications were assessed.
Results
Excluding the elbow extensor strength of 3 elbows in the BM group, which could not be measured too week. The extension/flexion ratio was as follows: in the BM group, 0.61 and in the MIS group, 0.93 on the affected side and 0.81 on the healthy side. For the MIS group, in which measurements could be performed on both the sides, the “affected/healthy side ratio” was 0.72 in flexion and 0.91 in extension. In terms of complications, skin trouble was found on 2 elbows in the BM group and on 1 elbow in the MIS group; further, rupture of the triceps tendon was suspected in 3 elbows in the BM group but was not found in the MIS group.
Discussion
In our study, deficiency in triceps muscle was found in 3 of 13 elbows with the Bryan & Morrey approach. MISTEA method may be the reason for prevention of deficiency or rupture of the triceps tendon. The MIS group had higher extension/flexion ratio in the affected side, suggesting the possibility that either the extensor strength had increased or the flexor strength had weakened. Further, in the MIS group, the extension showed an “affected/healthy side” ratio, which means that an extensor strength almost equivalent to that of the healthy side was maintained, whereas the flexor strength was 72% of that on the healthy side, suggesting that the flexor strength may have decreased. Loss of the flexor strength may be because the MISTEA method involves partial release of the brachialis muscle and the joint's center of rotation to move slightly towards the proximal side.
