Abstract
There are only a few studies which could support conclusions concerning the strength
of the muscles surrounding the hip Joint and especially concerning the strength relationships
following implantation of endo-prostheses. The aim of this study was to examine the
postoperative course of strength deficits in this musculature compared to clinical
parameters.
Fifty-eight patients between 30 and 67 years of age, in whom individual total hip
prostheses were implanted, were clinically examined prior, 9 weeks and 6 months after
surgery. Moreover, the maximum isometric strengths of abductors, flexors, and rotator
muscles as well as maximum isokinetic strengths of the extensors and flexor musculature
at 607s and 1207s were measured.
The flexor and extensor musculature already showed a clear increase in maximum strength
after 9 weeks and 6 months. By contrast, the isometric strengths of the rotators increased
only slightly, the abductor strength decreased after 9 weeks to below the preoperative
baseline level and attained this level again only after 6 months. The clinical parameters
Trendelenburg sign, limping, and Walking capacity were clearly improved after 6 months,
but no correlation to the abductor strength could be demonstrated.
It is concluded that limp-free gait can be attained even without maximum strength
increase in the abductors, which are important for fluid gait, at least for short
distances. The importance of regular training of the rotator and abductor musculature
in coxarthrosis is emphasized to delay limitation of movement and decreased strength
in the sense of a capsule pattern.
Key words
Isometric - isokinetic - total hip prostheses - coxarthrosis - strength deficits -
walking capacity
