E. Doran

Comparison of hip and knee arthroplasty outcomes at early and intermediate follow-up.

A common perception among clinicians and patients is that recovery is similar following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Improvement in the outcomes of 337 THAs and 256 TKAs implanted by the same surgeon between April 2003 and November 2005 were compared. Improvement was measured using changes in Oxford hip and knee scores measured preoperatively, at first follow-up, and 1 year postoperatively for each patient. Improvements between preoperative review and first follow-up and between preoperative review and 1-year postoperative follow-up were significantly greater for THA compared to TKA patients. Improvements between first postoperative follow-up and 1-year postoperative follow-up were not significantly different between THA and TKA patients. Although THA patients displayed a significantly worse score preoperatively, they displayed a significantly better score at both first follow-up and 1-year postoperative follow-up. While both procedures improve postoperative pain and physical function, as measured by the Oxford score, improvements measured relative to preoperative levels were significantly smaller for TKA compared to THA patients. Despite recent advances in knee arthroplasty surgery, a significant proportion of TKA patients achieve relatively poor outcome scores postoperatively. This study shows that pain and function improve less and more slowly in the early and intermediate postoperative periods for knee compared to hip arthroplasty patients.

Aspirin for thromboprophylaxis after primary lower limb arthroplasty: early thromboembolic events and 90 day mortality in 11 459 patients

AIMS The aim of this study was to present data on 11 459 patients who underwent total hip (THA), total knee (TKA) or unicompartmental knee arthroplasty (UKA) between November 2002 and April 2014 with aspirin as the primary agent for pharmacological thromboprophylaxis. PATIENTS AND METHODS We analysed the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) then compared the 90-day all-cause mortality with the corresponding data in the National Joint Registry for England and Wales (NJR). RESULTS The incidence of PE was 0.6% after THA, 1.47% after TKA and 1.2% after UKA. The 90-day mortality was 0.39% after THA and 0.44% after TKA. No deaths occurred after UKA. The main causes of death were ischaemic heart disease and respiratory failure. PE was responsible for only 18% of deaths. There was a decline in 90-day mortality, from 0.64% between 2002 and 2007, to 0.21% between 2008 and 2013 after THA, and from 0.47% to 0.39% after TKA for the corresponding period. The standardised mortality ratio (SMR) declined from 86.5 (confidence interval (CI) 63.0 to 137.7) to 39.7 (CI 31.2 to 54.3) p = 0.024. The incidence of proximal DVT was 0.3%. TAKE HOME MESSAGE With individualised risk assessment and as part of a multimodal approach, Aspirin is safe to use as the main thromboprophylactic agent in primary arthroplasty. It is not associated with an increased incidence of symptomatic DVT, PE or death.

The use of a posterior lip augmentation device for a revision of recurrent dislocation after primary cemented Charnley/Charnley Elite total hip replacement

Between April 1992 and July 2005, 310 posterior lip augmentation devices were used for the treatment of recurrent dislocation of the hip in 307 patients who had received primary total hip replacements (THRs) using Charnley/Charnley Elite components with a cemented acetabulum. The mean number of dislocations before stabilisation with the device was five (1 to 16) with a mean time to this intervention from the first dislocation of 3.8 years (0 days to 22.5 years). The mean age of the patients at this reconstruction was 75.4 years (39 to 96). A retrospective clinical and radiological review was carried out at a mean follow-up of six years and nine months (4.4 months to 13 years and 7 months). Of the 307 patients, 53 had died at the time of the latest review, with a functioning THR and with the posterior lip augmentation device in situ. There were four revisions (1.3%), one for pain, two for deep infection and one for loosening of the acetabular component. Radiolucent lines around the acetabular component increased in only six cases after insertion of the device which was successful in eliminating instability in 302 patients, with only five further dislocations (1.6%) occurring after its insertion.

Intra-operative and short term outcome of total knee arthroplasty in morbidly obese patients

BACKGROUND Longer operation times, poorer patient outcomes and increased early post-operative complications are reasons cited for not undertaking total knee arthroplasty (TKA) on morbidly obese patients. This study tests the hypothesis that there is no difference in intra-operative parameters between morbidly obese and non-obese patients, and no difference in patient outcome. METHODS Intra-operative parameters, post-operative complications, patient outcomes and knee range of motion were compared between morbidly obese patients (BMI>40 kg/m2) and individually age and gender matched non-obese patients (BMI<30 kg/m2) undergoing cementless rotating platform TKA. RESULTS Anaesthetic times and length of hospital stay were not significantly different between the morbidly obese and non-obese patients. Surgical time was significantly greater in morbidly obese patients. Improvements in patient outcomes following TKA were not significantly different between the morbidly obese and non-obese patients at early and short-term follow-up. CONCLUSIONS In contrast to previous studies, post-operative complication rates within three months of surgery and up to one year post-operatively were not significantly higher for morbidly obese patients. LEVEL OF EVIDENCE III.

The influence of immediate knee flexion on blood loss and other parameters following total knee replacement

In an initial randomised controlled trial (RCT) we segregated 180 patients to one of two knee positions following total knee replacement (TKR): six hours of knee flexion using either a jig or knee extension. Outcome measures included post-operative blood loss, fall in haemoglobin, blood transfusion requirements, knee range of movement, limb swelling and functional scores. A second RCT consisted of 420 TKR patients randomised to one of three post-operative knee positions: flexion for three or six hours post-operatively, or knee extension. Positioning of the knee in flexion for six hours immediately after surgery significantly reduced blood loss (p = 0.002). There were no significant differences in post-operative range of movement, swelling, pain or outcome scores between the various knee positions in either study. Post-operative knee flexion may offer a simple and cost-effective way to reduce blood loss and transfusion requirements following TKR. We also report a cautionary note regarding the potential risks of prolonged knee flexion for more than six hours observed during clinical practice in the intervening period between the two trials, with 14 of 289 patients (4.7%) reporting lower limb sensory neuropathy at their three-month review.

Five-year clinical and radiological outcomes in 257 consecutive cementless Oxford medial unicompartmental knee arthroplasties

Aims Our aim was to examine the clinical and radiographic outcomes in 257 consecutive Oxford unicompartmental knee arthroplasties (OUKAs) (238 patients), five years post‐operatively. Patients and Methods A retrospective evaluation was undertaken of patients treated between April 2008 and October 2010 in a regional centre by two non‐designing surgeons with no previous experience of UKAs. The Oxford Knee Scores (OKSs) were recorded and fluoroscopically aligned radiographs were assessed post‐operatively at one and five years. Results The median age of the 238 patients was 65.0 years (interquartile range (IQR) 59.0 to 73.0), the median body mas index was 30.0 (IQR 27.5 to 33.0) and 51.7% were male. There were no intra‐operative complications. There was a significant improvement in the median OKS at six weeks (34, IQR 31.0 to 37.0), one year (38, IQR 29.0 to 43.0) and five years (37, IQR 27.0 to 42.0) when compared with the pre‐operative scores (16, IQR 13.0 to 19.0) (all p = < 0.01). No patient had progressive radiolucent lines or loosening. A total of 16 patients had died by five years. The cumulative survival at five years was 98.8% and the mean survival time was 5.8 years (95% confidence interval 5.6 to 5.9). A total of seven OUKAs (2.7%) were revised; three within five years and four thereafter, between 5.1 and 5.7 years post‐operatively. Five (1.9%) had re‐operations within five years. Conclusion The proportion of patients requiring revision at five years is lower than that generally reported for UKA. These findings add support for the use of the cementless OUKA outside the design centre. Longer follow‐up is required.