This study aimed to quantify the shoulder kinematics during an apprehension-relocation test in patients with anterior shoulder instability (ASI) and glenoid bone loss using the radiostereometric analysis (RSA) method. Kinematics were compared with the patient’s contralateral healthy shoulder. A total of 20 patients with ASI and > 10% glenoid bone loss and a healthy contralateral shoulder were included. RSA imaging of the patient’s shoulders was performed during a repeated apprehension-relocation test. Bone volume models were generated from CT scans, marked with anatomical coordinate systems, and aligned with the digitally reconstructed bone projections on the RSA images. The glenohumeral joint (GHJ) kinematics were evaluated in the anteroposterior and superoinferior direction of: the humeral head centre location relative to the glenoid centre; and the humeral head contact point location on the glenoid.Aims
Methods
We evaluated results at one year after surgical
correction of internal rotation deformities in the shoulders of
270 patients with obstetric brachial plexus palsy. The mean age
at surgery was 6.2 years (0.6 to 35). Two techniques were used:
open subscapularis elongation and latissimus dorsi to infraspinatus
transfer. In addition, open relocation was performed or attempted
in all patients with subluxed or dislocated joints. A mixed effects
model approach was used to evaluate the effects of surgery on internal
and external rotation, abduction, flexion and Mallet score. Independent
factors included operative status (pre- or post-operative), gender,
age, the condition of the joint, and whether or not transfer was
performed. The overall mean improvement in external rotation following
surgery was 84.6° (95% confidence interval (CI) 80.2 to 89.1) and
the mean Mallet score improved by 4.0 (95% CI 3.7 to 4.2). There was
a mean decrease in internal rotation of between 27.6° and 34.4°
in the relocated joint groups and 8.6° (95% CI 5.2 to 12.0) in the
normal joint group. Abduction and flexion were unchanged following
surgery. Adding a latissimus dorsi transfer did not result in greater
improvement in the mean external rotation compared with elongation
of the subscapularis alone. Cite this article:
Metal-on-metal (MoM) hip resurfacing was introduced into clinical
practice because it was perceived to be a better alternative to
conventional total hip replacement for young and active patients.
However, an increasing number of reports of complications have arisen
focusing on design and orientation of the components, the generation
of metallic wear particles and serum levels of metallic ions. The
procedure introduced a combination of two elements: large-dimension
components and hard abrasive particles of metal wear. The objective
of our study was to investigate the theory that microseparation
of the articular surfaces draws in a high volume of bursal fluid
and its contents into the articulation, and at relocation under
load would generate high pressures of fluid ejection, resulting
in an abrasive water jet. This theoretical concept using MoM resurfacing components (head
diameter 55 mm) was modelled mathematically and confirmed experimentally
using a material-testing machine that pushed the head into the cup
at a rate of 1000 mm/min until fully engaged.Objectives
Methods
The most common injury in rugby resulting in
spinal cord injury (SCI) is cervical facet dislocation. We report
on the outcome of a series of 57 patients with acute SCI and facet
dislocation sustained when playing rugby and treated by reduction
between 1988 and 2000 in Conradie Hospital, Cape Town. A total of
32 patients were completely paralysed at the time of reduction.
Of these 32, eight were reduced within four hours of injury and
five of them made a full recovery. Of the remaining 24 who were
reduced after four hours of injury, none made a full recovery and only
one made a partial recovery that was useful. Our results suggest
that low-velocity trauma causing SCI, such as might occur in a rugby
accident, presents an opportunity for secondary prevention of permanent
SCI. In these cases the permanent damage appears to result from
secondary injury, rather than primary mechanical spinal cord damage.
In common with other central nervous system injuries where ischaemia
determines the outcome, the time from injury to reduction, and hence
reperfusion, is probably important. In order to prevent permanent neurological damage after rugby
injuries, cervical facet dislocations should probably be reduced
within four hours of injury.
We report the clinical and radiological outcome of total ankle replacement performed in conjunction with hindfoot fusion or in isolation. Between May 2003 and June 2008, 60 ankles were treated with total ankle replacement with either subtalar or triple fusion, and the results were compared with a control group of 288 ankles treated with total ankle replacement alone. After the mean follow-up of 39.5 months (12 to 73), the ankles with hindfoot fusion showed significant improvement in the mean visual analogue score for pain (p <
0.001), the mean American Orthopaedic Foot and Ankle Society score (p <
0.001), and the mean of a modified version of this score (p <
0.001). The mean visual analogue pain score (p = 0.304) and mean modified American Orthopaedic Foot and Ankle Society score (p = 0.119) were not significantly different between the hindfoot fusion and the control groups. However, the hindfoot fusion group had a significantly lower mean range of movement (p = 0.009) and a higher rate of posterior focal osteolysis (p = 0.04). Both groups showed various complications (p = 0.131) and failure occurring at a similar rate (p = 0.685). Subtalar or triple fusion is feasible and has minimal adverse effects on ankles treated with total ankle replacement up to midterm follow-up. The clinical outcome of total ankle replacement when combined with hindfoot fusion is comparable to that of ankle replacement alone. Thus, hindfoot fusion should be performed in conjunction with total ankle replacement when indicated.
In 12 patients, we measured the oxygen concentration in the femoral head-neck junction during hip resurfacing through the anterolateral approach. This was compared with previous measurements made for the posterior approach. For the anterolateral approach, the oxygen concentration was found to be highly dependent upon the position of the leg, which was adjusted during surgery to provide exposure to the acetabulum and femoral head. Gross external rotation of the hip gave a significant decrease in oxygenation of the femoral head. Straightening the limb led to recovery in oxygen concentration, indicating that the blood supply was maintained. The oxygen concentration at the end of the procedure was not significantly different from that at the start. The anterolateral approach appears to produce less disruption to the blood flow in the femoral head-neck junction than the posterior approach for patients undergoing hip resurfacing. This may be reflected subsequently in a lower incidence of fracture of the femoral neck and avascular necrosis.
Chronic patellofemoral instability can be a disabling condition. Management of patients with this condition has improved owing to our increased knowledge of the functional anatomy of the patellofemoral joint. Accurate assessment of the underlying pathology in the unstable joint enables the formulation of appropriate treatment. The surgical technique employed in patients for whom non-operative management has failed should address the diagnosed abnormality. We have reviewed the literature on the stabilising features of the patellofemoral joint, the recommended investigations and the appropriate forms of treatment.
Four men who presented with chronic dislocation of the radial head and nonunion or malunion of the ulna were reviewed after open reduction of the radial head and internal fixation of the ulna in attempted overcorrection. Their mean age was 37 years (28 to 46) and the mean interval between injury and reconstruction was nine months (4 to 18). The mean follow-up was 24 months (15 to 36). One patient who had undergone secondary excision of the radial head was also followed up for comparison. The three patients who had followed the treatment protocol had nearly normal flexion, extension and supination and only very occasional pain. All had considerable loss of pronation which did not affect patient satisfaction. Preservation of the radial head in chronic adult Monteggia fractures appears to be a promising mode of treatment.
The contributions made by metatarsus primus varus, medial subluxation of the navicular, and angulation of the neck of the talus to the residual deformity in treated club feet were assessed from radiographs. Their relation to the appearance of the feet, to the age of the patient, to the results of operations, and to the age at the time of the first operation were investigated. Lateral rotation of the ankle and flattening of the talus were also studied. Medial subluxation of the navicular was found to be the most important factor influencing both the appearance of the feet and the lateral rotation of the ankle.