In metal-on-metal (MoM) hip arthroplasties and resurfacings, mechanically induced corrosion can lead to elevated serum metal ions, a local inflammatory response, and formation of pseudotumours, ultimately requiring revision. The size and diametral clearance of anatomical (ADM) and modular (MDM) dual-mobility polyethylene bearings match those of Birmingham hip MoM components. If the acetabular component is satisfactorily positioned, well integrated into the bone, and has no surface damage, this presents the opportunity for revision with exchange of the metal head for ADM/MDM polyethylene bearings without removal of the acetabular component. Between 2012 and 2020, across two centres, 94 patients underwent revision of Birmingham MoM hip arthroplasties or resurfacings. Mean age was 65.5 years (33 to 87). In 53 patients (56.4%), the acetabular component was retained and dual-mobility bearings were used (DM); in 41 (43.6%) the acetabulum was revised (AR). Patients underwent follow-up of minimum two-years (mean 4.6 (2.1 to 8.5) years).Aims
Methods
Surgical site infection (SSI) is a common complication of surgery
with an incidence of about 1% in the United Kingdom. Sutures can
lead to the development of a SSI, as micro-organisms can colonize
the suture as it is implanted. Triclosan-coated sutures, being antimicrobical,
were developed to reduce the rate of SSI. Our aim was to assess
whether triclosan-coated sutures cause a reduction in SSIs following
arthroplasty of the hip and knee. This two-arm, parallel, double-blinded study involved 2546 patients
undergoing elective total hip (THA) and total knee arthroplasty
(TKA) at three hospitals. A total of 1323 were quasi-randomized
to a standard suture group, and 1223 being quasi-randomized to the
triclosan-coated suture group. The primary endpoint was the rate
of SSI at 30 days postoperatively.Aims
Patients and Methods
A fracture of the hip is the most common serious orthopaedic
injury, and surgical site infection (SSI) is one of the most significant
complications, resulting in increased mortality, prolonged hospital
stay and often the need for further surgery. Our aim was to determine
whether high dose dual antibiotic impregnated bone cement decreases the
rate of infection. A quasi-randomised study of 848 patients with an intracapsular
fracture of the hip was conducted in one large teaching hospital
on two sites. All were treated with a hemiarthroplasty. A total
of 448 patients received low dose single-antibiotic impregnated
cement (control group) and 400 patients received high dose dual-antibiotic impregnated
cement (intervention group). The primary outcome measure was deep
SSI at one year after surgery.Aims
Patients and Methods
We investigated the capacity of patient warming
devices to disrupt the ultra-clean airflow system. We compared the effects
of two patient warming technologies, forced-air and conductive fabric,
on operating theatre ventilation during simulated hip replacement
and lumbar spinal procedures using a mannequin as a patient. Infection
data were reviewed to determine whether joint infection rates were
associated with the type of patient warming device that was used. Neutral-buoyancy detergent bubbles were released adjacent to
the mannequin’s head and at floor level to assess the movement of
non-sterile air into the clean airflow over the surgical site. During
simulated hip replacement, bubble counts over the surgical site
were greater for forced-air than for conductive fabric warming when
the anaesthesia/surgery drape was laid down (p = 0.010) and at half-height
(p <
0.001). For lumbar surgery, forced-air warming generated
convection currents that mobilised floor air into the surgical site
area. Conductive fabric warming had no such effect. A significant increase in deep joint infection, as demonstrated
by an elevated infection odds ratio (3.8, p = 0.024), was identified
during a period when forced-air warming was used compared to a period
when conductive fabric warming was used. Air-free warming is, therefore,
recommended over forced-air warming for orthopaedic procedures.
There have been no large comparative studies of the blood levels of metal ions after implantation of commercially available hip resurfacing devices which have taken into account the effects of femoral size and inclination and anteversion of the acetabular component. We present the results in 90 patients with unilateral articular surface replacement (ASR) hip resurfacings (mean time to blood sampling 26 months) and 70 patients with unilateral Birmingham Hip Resurfacing (BHR) implants (mean time 47 months). The whole blood and serum chromium (Cr) and cobalt (Co) concentrations were inversely related to the size of the femoral component in both groups (p <
0.05). Cr and Co were more strongly influenced by the position of the acetabular component in the case of the ASR, with an increase in metal ions observed at inclinations >
45° and anteversion angles of <
10° and >
20°. These levels were only increased in the BHR group when the acetabular component was implanted with an inclination >
55°. A significant relationship was identified between the anteversion of the BHR acetabular component and the levels of Cr and Co (p <
0.05 for Co), with an increase observed at anteversion angles <
10° and >
20°. The median whole blood and serum Cr concentrations of the male ASR patients were significantly lower than those of the BHR men (p <
0.001). This indicates that reduced diametral clearance may equate to a reduction in metal ion concentrations in larger joints with satisfactory orientation of the acetabular component.
