Contemporary indications for unicompartmental knee replacement (UKR) include bone on bone radiographic changes in the medial compartment with relatively preserved lateral and patellofemoral compartments. The role of MRI in identifying candidates for UKR is commonplace. The aim of this study was to assess the relationship between radiographic and MRI pre-operative grade and outcome following UKR. A retrospective analysis of medial UKR patients from 2017 to 2021. Inclusion criteria were medial UKR for osteoarthritis with pre-operative and post-operative Oxford Knee Scores (OKS), pre-operative radiographs and MRI. 89 patients were included. Whilst all patients had grade 4 ICRS scores on MRI, 36/89 patients had grade 3 KL radiographic scores in the medial compartment, 50/89 had grade 4 KL scores on the medial compartment. Grade 3 KL with grade 4 IRCS medial compartment patients had a mean OKS change of 17.22 (Sd 9.190) meanwhile Grade 4 KL had a mean change of 17.54 (SD 9.001), with no statistical difference in the OKS change score following UKR between these two groups (p=0.873). Medial bone oedema was present in all but one patient. Whilst lateral compartment MRI ICRS scores ranged from 1 to 4 there was no association with MRI score of the lateral compartment and subsequent change in oxford score (P value 0.458). Patellofemoral Compartment (PFC) MRI ICRS ranged from 0 to 4. There was no association between PFC ICRS score and subsequent change in oxford knee score (P value .276) Radiographs may under report severity of some medial sided knee osteoarthritis. We conclude that in patients with grade 3 KL score that would normally not be considered for UKR, pre-operative MRI might identify grade 4 ICRS scores and this subset of patients have equivalent outcomes to patients with radiographic Grade 4 KL medial compartment osteoarthritis.
Treatment of prosthetic joint infection (PJI) following total knee arthroplasty (TKA) may guided by PJI classification, taking into account infection duration and potential for biofilm formation. Debridement, antibiotics and implant retention (DAIR) is recommended for ‘post-operative’ and ‘acute’ haematogenous PJI. However, the time cut-off for ‘post-operative’ PJI varies across classification systems. Furthermore, poor DAIR success rates have been reported in acute haematogenous PJIs. This study aimed to determine the success of DAIR in a large cohort of PJIs, and assess the utility of current classification systems for predicting DAIR outcomes. In this multicentre retrospective, cohort study, we identified 230 patients undergoing DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors were identified, and PJI subtype, post-operative antibiotic regime and treatment outcomes were recorded. Statistical analysis was performed to identify factors associated with failed DAIR, and success rates were analysed by multiple classification systems using receiver operating characteristic (ROC) curves.Introduction
Method
The coronavirus disease 2019 (COVID-19) pandemic presents significant challenges to healthcare systems globally. Orthopaedic surgeons are at risk of contracting COVID-19 due to their close contact with patients in both outpatient and theatre environments. The aim of this review was to perform a literature review, including articles of other coronaviruses, to formulate guidelines for orthopaedic healthcare staff. A search of Medline, EMBASE, the Cochrane Library, World Health Organization (WHO), and Centers for Disease Control and Prevention (CDC) databases was performed encompassing a variety of terms including ‘coronavirus’, ‘covid-19’, ‘orthopaedic’, ‘personal protective environment’ and ‘PPE’. Online database searches identified 354 articles. Articles were included if they studied any of the other coronaviruses or if the basic science could potentially applied to COVID-19 (i.e. use of an inactivated virus with a similar diameter to COVID-19). Two reviewers independently identified and screened articles based on the titles and abstracts. 274 were subsequently excluded, with 80 full-text articles retrieved and assessed for eligibility. Of these, 66 were excluded as they compared personal protection equipment to no personal protection equipment or referred to prevention measures in the context of bacterial infections.Aim
Methods
Osteolysis, secondary to local and systemic physiological effects, is a major challenge in total hip arthroplasty (THA). While osteolytic defects are commonly observed in long-term follow-up, how such lesions alter the distribution of stress is unclear. The aim of this study was to quantitatively describe the biomechanical implication of such lesions by performing subject-specific finite-element (FE) analysis on patients with osteolysis after THA. A total of 22 hemipelvis FE models were constructed in order to assess the transfer of load in 11 patients with osteolysis around the acetabular component of a THA during slow walking and a fall onto the side. There were nine men and two women. Their mean age was 69 years (55 to 81) at final follow-up. Changes in peak stress values and loads to fracture in the presence of the osteolytic defects were measured.Aims
Patients and Methods
We compared the rate of revision for instability
after total hip replacement (THR) when lipped and non-lipped acetabular
liners were used. We hypothesised that the use of a lipped liner
in a modular uncemented acetabular component reduces the risk of
revision for instability after primary THR. Using data from the
New Zealand Joint Registry, we found that the use of a lipped liner
was associated with a significantly decreased rate of revision for instability
and for all other indications. Adjusting for the size of the femoral
head, the surgical approach and the age and gender of the patient,
this difference remained strongly significant (p <
0.001). We conclude that evidence from the New Zealand registry suggests
that the use of lipped liners with modular uncemented acetabular
components is associated with a decreased rate of revision for instability
after primary THR. Cite this article:
Tapered, fluted, modular, titanium stems are
increasingly popular in the operative management of Vancouver B2 and
selected B3 peri-prosthetic femoral fractures. We have reviewed
the results at our institution looking at stem survival and clinical
outcomes and compared this with reported outcomes in the literature.
Stem survival at a mean of 54 months was 96% in our series and 97%
for combined published cases. Review of radiology showed maintenance
or improvement of bone stock in 89% of cases with high rates of
femoral union. Favourable clinical outcome scores have reported
by several authors. No difference in survival or clinical scores
was observed between B2 and B3 fractures. Tapered stems are a useful
option in revision for femoral fracture across the spectrum of femoral
bone deficiency. Cite this article:
Tapered, fluted, modular, titanium stems have
a long history in Europe and are increasing in popularity in North America.
We have reviewed the results at our institution looking at stem
survival and clinical outcomes. Radiological outcomes and quality
of life assessments have been performed and compared to cylindrical
non-modular cobalt chromium stems. Survival at five years was 94%.
This fell to 85% at ten years due to stem breakage with older designs.
Review of radiology showed maintenance or improvement of bone stock
in 87% of cases. Outcome scores were superior in tapered stems despite
worse pre-operative femoral deficiency. Tapered stems have proved
to be a useful alternative in revision total hip arthroplasty across
the spectrum of femoral bone deficiency.
Antibiotic impregnated articulating spacers are
used in two-stage revision total knee arthroplasty to deliver local antibiotic
therapy while preserving function. We have observed infection control
in greater than 95% of cases with functional outcomes approaching
those seen in revision for aseptic loosening. Higher failure has
been observed with methicillin resistant organisms.
