Intact abductors of the hip play a crucial role
in preventing limping and are known to be damaged through the direct lateral
approach. The extent of trauma to the abductors after revision total
hip replacement (THR) is unknown. The aim of this prospective study
was to compare the pre- and post-operative status of the gluteus
medius muscle after revision THR. We prospectively compared changes
in the muscle and limping in 30 patients who were awaiting aseptic
revision THR and 15 patients undergoing primary THR. The direct
lateral approach as described by Hardinge was used for all patients.
MRI scans of the gluteus medius and functional analyses were recorded
pre-operatively and six months post-operatively. The overall mean
fatty degeneration of the gluteus medius increased from 35.8% (1.1
to 98.8) pre-operatively to 41% (1.5 to 99.8) after multiple revision
THRs (p = 0.03). There was a similar pattern after primary THR,
but with considerably less muscle damage (p = 0.001), indicating
progressive muscle damage. Despite an increased incidence of a positive
Trendelenburg sign following revision surgery (p = 0.03) there was
no relationship between the cumulative fatty degeneration in the
gluteus medius and a positive Trendelenburg sign (p = 0.26). The
changes associated with other surgical approaches to the hip warrant
investigation. Cite this article:
Instability after total knee replacement (TKR)
accounts for 10% to 22% of revision procedures. All patients who
present for evaluation of instability require a thorough history to
be taken and physical examination, as well as appropriate imaging.
Deep periprosthetic infection must be ruled out by laboratory testing
and an aspiration of the knee must be carried out. The three main
categories of instability include flexion instability, extension instability
(symmetric and asymmetric), and genu recurvatum. Most recently,
the aetiologies contributing to, and surgical manoeuvres required
to correct, flexion instability have been elucidated. While implant
design and patient-related factors may certainly contribute to the
aetiology, surgical technique is also a significant factor in all
forms of post-operative instability. Cite this article:
Substantial healthcare resources have been devoted
to computer navigation and patient-specific instrumentation systems
that improve the reproducibility with which neutral mechanical alignment
can be achieved following total knee replacement (TKR). This choice of
alignment is based on the long-held tenet that the alignment of
the limb post-operatively should be within 3° of a neutral mechanical
axis. Several recent studies have demonstrated no significant difference
in survivorship when comparing well aligned Review of the literature suggests that a neutral mechanical axis
remains the optimal guide to alignment. Cite this article:
Instability after arthroplasty of the shoulder
is difficult to correct surgically. Soft-tissue procedures and revision surgery
using unconstrained anatomical components are associated with a
high rate of failure. The purpose of this study was to determine
the results of revision of an unstable anatomical shoulder arthroplasty
to a reverse design prosthesis. Between 2004 and 2007, 33 unstable
anatomical shoulder arthroplasties were revised to a reverse design.
The mean age of the patients was 71 years (53 to 86) and their mean
follow-up was 42 months (25 to 71). The mean time to revision was
26 months (4 to 164). Pain scores improved significantly (pre-operative
visual analogue scale (VAS) of 7.2 ( Cite this article: