Steroids Significantly Decrease Postoperative Postural Hypotension in Total Knee Replacement.

Total knee replacement (TKR) is one of the most common orthopaedic procedures performed, and enhanced recovery after surgery (ERAS) has been developed and incorporated into inpatient surgical pathways to improve patient outcomes. Under ERAS recommendations, multimodal prophylaxis has been used to help manage postoperative nausea and vomiting (PONV) following TKR. Dexamethasone is one of the commonly used for this and the anti-inflammatory properties could depress vagal activity, reducing postural hypotension (PH). The hypothesis of this study is that postoperative dexamethasone use is associated with lower rates of early postoperative PH following TKR surgery. In our institution, patients who undergo elective primary TKR are admitted on the day of surgery and follow a standardized ERAS protocol. Data on patients who underwent elective primary TKR under a single adult reconstruction team from September 2017 to March 2020 were reviewed and analyzed. A review of demographic characteristics, surgical data, postoperative medications, and postoperative notes was performed. Binary logistic regression was used to assess the effect of the use of dexamethasone on PH, with an adjusted odds ratio (OR) calculated after accounting for potential confounders. Of the 149 patients were included in the study, 78 had dexamethasone postoperatively, and 71 did not. Patients who had received dexamethasone were statistically less likely to suffer from PH (OR = 0.31, p = 0.03) and less likely to develop PONV (OR = 0.21, p = 0.006). Patients who had received dexamethasone were more likely able to participate in early physiotherapy (OR = 2.42, p = 0.14), and this result was statistically insignificant. The use of postoperative intravenous dexamethasone is significantly associated with lower rates of postoperative PH after TKR. However, more studies are required to assess the optimal dosing amount and frequency, as well as to assess other factors which can enhance early postoperative patient mobilization as part of our goals for ERAS. This therapeutic study reflects level of evidence III.

Gap formation after single lateral row versus dual-row suture bridge cuff repair: An ovine biomechanical model.

BACKGROUND: The aim of this study is to compare two types of suture bridging constructs; a laterally based bridging single row (SR) construct and a classic dual row (DR) suture bridge construct. The hypothesis is that the DR construct will demonstrate superior biomechanical properties. METHODS: Six matched pairs of sheep infraspinatus tendon tears repaired with these two different types of suture bridging techniques were tested for gap formation, ultimate failure load and mode of failure. The specimens were pre-cycled for 10 cycles before they were subjected to a constant pre-load of 10N. The specimens were then subjected to cyclic loading at a speed of 8.33 mm/s. The test was stopped after every 500 cycles for a total of 3000 cycles. RESULTS: Mean gap formation after 3000 cycles was lower in the DR group (0.81 ± 0.2 mm versus 2.44 ± 0.27 mm; p = 0.002). Mean change in gap (with every 500 cycles) was also lesser for the DR group after 1500 cycles. DR repairs failed at a higher load (523.4 ± 80.4 N) compared to the SR repairs (452.3 ± 66.3 N) but this did not reach significance. All repairs failed with sutures pulling through the tendon during load to failure testing. CONCLUSIONS: Gap formation is significantly lower with a dual row suture bridge construct than a laterally based bridging single row construct. LEVEL OF EVIDENCE: Biomechanical study.

The Outcome of Total Knee Arthroplasty With and Without Patellar Resurfacing up to 17 Years: A Report From the Australian Orthopaedic Association National Joint Replacement Registry.

BACKGROUND: Patellar resurfacing in total knee arthroplasty (TKA) remains a controversial issue after more than 4 decades of TKA. Despite a growing body of evidence from registry data, resurfacing is still based largely on a surgeon's preference and training. The purpose of this study is to provide long-term outcomes for patellar resurfaced compared to when the patella is not resurfaced. METHODS: Data from the Australian Orthopaedic Association National Joint Replacement Registry (1999-2017) were used for this study. The analysis included 570,735 primary TKAs undertaken for osteoarthritis. Hazard ratios (HRs) and 17-year cumulative percent revision rates were used to compare revision rates between 4 subgroups: minimally stabilized (MS) patellar resurfacing, posterior stabilized (PS) patellar resurfacing, MS unresurfaced, and PS unresurfaced patella. Additional analyses of the patellar implant type and a comparison of inlay and onlay patellar resurfacing were also performed. RESULTS: For all primary TKA, procedures where the patella was not resurfaced have a higher rate of revision compared to procedures where the patella was resurfaced (HR, 1.31; confidence interval, 1.28-1.35; P < .001). Unresurfaced PS knees have the highest cumulative percent revision at 17 years (11.1%), followed by MS unresurfaced (8.8%), PS resurfaced (7.9%), and MS resurfaced (7.1%). Inlay patellar resurfacing has a higher rate of revision compared to onlay patellar resurfacing (HR, 1.27; confidence interval, 1.17-1.37; P < .001). CONCLUSION: Resurfacing the patella reduces the rate of revision for both MS and PS knees. MS knees with patellar resurfacing have the lowest rate of revision. Onlay patella designs are associated with a lower revision rate compared to inlay patella designs.

On-Table and Short-Term Mortality: A Single-Institution Experience With Cementing All Hip Arthroplasties for Neck of Femur Fractures.

BACKGROUND: To review on-table, day 0, day 1, day 7, and day 30 mortality after hemiarthroplasty or total hip arthroplasty (THA) using cemented femoral stems for femoral neck fractures in order to evaluate risk factors for perioperative and short-term mortality. METHODS: The medical records of 751 consecutive cases with neck of femur fractures who underwent hemiarthroplasty (n = 602) or THA (n = 149) with cemented stems between January 2011 and December 2016 were retrospectively reviewed from a prospectively gathered database. The primary outcome measures were on-table, day 0, day 1, day 7, and day 30 mortality. Univariate and multivariate analyses were performed in order to identify various contributing patient and surgical variables. RESULTS: There were 2 on-table deaths (0.27%): one patient had a cardiorespiratory arrest at the time of inserting the femoral stem and the other had a cardiorespiratory arrest at the end of wound closure some 20 minutes after cementing. There were 3 further day 0 deaths meaning the day 0 mortality rate was 0.67% (5/751). All 5 patients were older than 80 years and had an American Society of Anesthesiologists grade 3 or more. The 1-day, 7-day, and 30-day mortality rates were 0.93% (7 patients), 2.7% (20 patients), and 6.8% (51 patients), respectively. There is significantly higher 30-day mortality risk associated with increasing American Society of Anesthesiologists grade (P < .001) when adjusted for age, gender, and type of surgery (hemiarthroplasty compared with THA). CONCLUSION: In our neck of femur fracture patients who were operated with cemented stems, 7-day and 30-day mortality rates were 2.7% and 6.8%, respectively. Cemented stems should be used with caution in elderly hip fracture patients with multiple comorbidities who are at high risk of perioperative mortality.

Hip hemiarthroplasty for femoral neck fractures in end-stage renal disease patients on dialysis compared to patients with late-stage chronic kidney disease.

INTRODUCTION: Hip fractures in patients with end-stage renal disease (ESRD) are associated with frequent complications and poorer outcomes. Patients on chronic dialysis are at additional risk of dialysis-related complications such as myocardial infarction and early osteolysis. We analysed the complications and implant survivorship of hemiarthroplasty in patients with femoral neck fractures with late-stage chronic kidney disease with and without pre-existing dialysis. METHODS: We conducted a retrospective case-control study of 28 patients with ESRD and 31 patients with chronic kidney disease (CKD) Stages 3-5, who had a total of 62 fractures treated with hemiarthroplasty between 2005 and 2015. The mean age of the patients was 68.33 (50.21-86.45) years. The mean follow-up time of the group was 39 months. Patient demographics, complications, outcomes and follow-up radiographs were analysed for differences. RESULTS: Patient in both groups had statistically similar demographics and comorbidity scores except for a higher incidence of hyperparathyroidism in ESRD patients on chronic dialysis (nine patients vs. zero patients; p = 0.001). These patients were more likely to develop cardiopulmonary complications in the perioperative period (odds ratio [OR] 5.04; p = 0.04) and implant loosening on radiographic analysis (OR 8.75; p = 0.02). The incidence of loosening was higher in patients with hyperparathyroidism (OR 9.80; p = 0.002). Cemented techniques, however, did not appear to be significantly associated with intraoperative fractures or loosening. CONCLUSION: Patients with ESRD on chronic dialysis were more likely to develop cardiopulmonary complications and implant loosening after hemiarthroplasty for femoral neck fractures. Hyperparathyroidism should be optimised, as it may prevent loosening. Our study did not show any difference in complications or outcomes for cemented fixation.

Alignment Analyses in the Varus Osteoarthritic Knee Using Computer Navigation.

Osteoarthritic (OA) knees with severe extension varus deformity seem to have correspondingly more severe flexion varus, especially beyond a certain tibiofemoral angle. Clinical measurement of flexion varus and fixed flexion deformity (FFD), which had been difficult to perform because of the spatial alignment of the knee in flexion, was recently made possible with computer navigation. We conducted a study to evaluate the relationship of extension and flexion varus in OA knees and to determine whether severity of FFD in the sagittal plane correlates with severity of coronal plane varus deformity. The study included 317 consecutive cases of computer-navigated total knee arthroplasty performed on OA knees with varus deformities. Three sets of values were extracted from the navigation data: varus angle at maximal knee extension, 90° knee flexion, and maximal knee extension. Correlation analyses were performed for extension and flexion varus, FFD, and coronal plane deformity. OA knees with extension varus of more than 10° had an incremental likelihood of more severe flexion varus. When the extension varus angle exceeded 20°, probability became almost certainty. There was no correlation between FFD and coronal plane varus deformity.