The purpose of this study is to assess the accuracy of component positioning and incidence of peri-operative and 90-day post-operative complications following robotic arm-assisted and conventional total hip arthroplasty (THA). Three groups of patients were analyzed for this study: those that underwent conventional THA performed by Surgeon 1, conventional THA performed by Surgeon 2, or robotic arm-assisted THA performed by Surgeon 2. All patients underwent primary uncemented THA via a posterior approach. Patient characteristics, intra-operative data, and 90-day post-operative complications were collected. Post-operative standing pelvic radiographs were utilized to measure acetabular position and to identify post-operative complications. Acetabular component position measurements revealed substantially less variation in both inclination and anteversion in the Surgeon 2 – Robotic group. Nine patients had intra-operative cables placed for intra-operative calcar fracture in the Surgeon 1 group compared to one patient and three patients in Surgeon 2 – Robotic and Surgeon 2 – Traditional groups, respectively. Nine instances of femoral stems subsidence were identified in the Surgeon 1 group compared to one patient in Surgeon 2 – Traditional. There were four instances of dislocation in the Surgeon 1 group compared to one in the Surgeon 2 – Robotic group. Robotic arm-assisted THA decreases the variation in acetabular component positioning compared to conventional THA. However, the benefit of this is unclear as there is little difference in dislocation rate. This study may demonstrate additional value in CT-based implant planning as this cohort had the lowest incidence of femoral component complications.
There is no consensus on the ideal pain management strategy following total hip arthroplasty (THA). This study sought to identify immediate changes in the hospital course of patients undergoing primary THA following implementation of a rapid recovery anesthesia and multimodal management of pain (RAMP) protocol. For this study, rapid recovery anesthesia describes the use of preoperative non-narcotic medication in conjunction with neuraxial anesthesia techniques confined to the operating room only. The multimodal pain regimen consists of pre- and post-operative high dose nonsteroidal anti-inflammatories (NSAIDs), gabapentin, and antiemetics with or without intraoperative periarticular anesthetic injection. We hypothesized that the implementation of a RAMP protocol would lead to decreased reported pain scores, decreased narcotic use, and a shorter hospital stay in patients undergoing primary THA. This retrospective cohort study performed at a multi-surgeon high-volume institution reviewed the records of 81 consecutive patients who underwent primary THA utilizing traditional anesthesia and an opioid-dependentpain management techniques between June to September 2014 compared to 78 patients who underwent primary THA after implementation of the RAMP protocol between November 2014 to February 2015. The length of stay (LOS), pain scores, narcotic use, and other clinical data were recorded for each study group. Equality of variance was confirmed prior to statistical analysis using t-test for equality of means.Introduction
Methods
Background: The direct anterior approach (DAA) for total hip arthroplasty (THA) has rapidly become popular, but there is little consensus regarding the risks and benefits of this approach in comparison with a modern posterior approach (PA). Methods: 2,147 patients who underwent DAA THA were propensity score matched with patients undergoing PA THA on the basis of age, gender, body-mass index (BMI) and American Society of Anaesthesia classification using data from a state joint replacement registry. Mean age of the matched cohort was 64.8 years, mean BMI was 29.1 kg/m2 and 53% were female. Multilevel logistic regression models using generalised estimating equations (GEEs) to control for grouping at the hospital level were utilised to identify differences in various outcomes. Results: There was no difference in the dislocation rate between patients undergoing DAA (0.84%) and PA (0.79%) THA. Trends indicating a slightly longer length of stay with the PA and a slightly greater risk of fracture, increased blood loss and hematoma with the DAA are consistent with previous studies. Conclusion: On the basis of short-term outcome and complication data, neither approach has a compelling advantage over each other, including no difference in the dislocation risk.
Tranexamic acid (TXA) has been shown to reduce post-operative blood loss, but the dosage and method of administration remains controversial. The purpose of our study was to study the effectiveness of topical TXA in a cohort of patients (n=224) undergoing TKA by a single surgeon. Two groups of patients who received topical TXA were compared to patients who did not receive TXA. Patients that received topical TXA had the least early postoperative blood loss, with patients that received topical TXA with a tourniquet and a drain having the least. Patients receiving TXA required fewer transfusions than patients who did not receive TXA and there was no difference in the rate of symptomatic DVT/PE. Our results support the use of topical TXA during TKA.
Digital templating is a critical part of preoperative planning for total hip arthroplasty (THA) that is increasingly used by orthopaedic surgeons as part of their preoperative planning process. Digital templating has been used as a method of reducing hospital costs by eliminating the need for acetate films and providing an accurate method of preoperative planning. Pre-operative templating can help anticipate and predict appropriate component sizes to help avoid postoperative leg length discrepancy, failure to restore offset, femoral fracture, and instability. A preoperative plan using digital radiographs for surgical templating for component size can improve intraoperative accuracy and precision. While templating on conventional and digital radiographs is reliable and accurate, the accuracy of templating on digital images acquired with a novel biplanar imaging system (EOS Imaging Inc, Cambridge, MA, USA) remains unknown. EOS imaging captures whole body images of a standing patient without stitching or vertical distortion, less magnification error and exposes patients to less radiation than a pelvis AP radiograph. Therefore, the purpose of this study was to compare EOS imaging and conventional anteroposterior (AP) xrays for preoperative digital templating for THA, and compare the results to the implant sizes used intraoperatively. Forty primary unilateral THA patients had preoperative supine AP xrays and standing EOS imaging. The mean age for patients was 61 ± 8 years, the mean body mass index 29 ± 6 kg/m2 and 21 patients were female. All patients underwent a THA with the same THA system (R3 Acetabular System and Synergy Cementless Stem, Smith & Nephew, TN, USA) by a single surgeon. Two blinded observers preoperatively templated using both AP xray and EOS imaging for each patient to predict acetabular size, femoral component size, and stem offset. All templating was performed by two observers with standard software (Ortho Toolbox, Sectra AB, Linköping, Sweden) [Figure 1] one week prior to surgery, and were compared using the Cronbach's alpha (∝) coefficient of reliability. The accuracy of templating was reported as the average percent agreement between the implanted size and the templated size for each component.Background
Methods
Sagittal pelvic tilt (PT) has been shown to effect the functional position of acetabular components in patients with total hip replacements (THR). This change in functional component position may have clinical implications including increased likelihood of wear or dislocation. Surgeons can use computer-assisted navigation intraoperatively to account for a patient's pelvic tilt and to adjust the position of the acetabular component. However, the accuracy of this technique has been questioned due to the concern that PT may change after THR. The purpose of this study was to measure the change in PT after THR, and to determine if preoperative clinical and radiographic parameters can predict PT changes after THR. 138 consecutive patients who underwent unilateral THR by one surgeon received standing bi-planar lumbar spine and lower extremity radiographs preoperatively and six weeks postoperatively. Patients with prior contralateral THR, conversion THR and instrumented lumbosacral fusions were excluded. PT and pelvic incidence (PI) were measured preoperatively for each patient, and PT was measured on the postoperative imaging. A negative value for PT indicated posterior pelvic tilt. Patient demographics were collected from the chart. Average age was 56.8±10.9 years, average BMI was 28.3±6.0 kg/m2, and 67 patients (48.6%) were female. Mean preoperative pelvic tilt was 0.6°±7.3° (range: −19.0° to 17.9°). We found greater than 10° of sagittal PT in 23 out of 138 (16.6%) patients in this sample. Mean post-operative pelvic tilt was 0.3°±7.4° (range: −18.4° to 15.0°). Mean change in pelvic tilt was −0.3°±3.6° (range: −9.6° to 13.5°). PT changed by less than 5° in 119 of 138 patients (86.2%). The mean difference in pre-operative and post-operative PT is not statistically significant (p = 0.395). Pre-operative PT was strongly correlated with post-operative PT (r2 = 0.88, p = 0.0001) (Figure 1). There was not a statistically significant relationship between PI and change in PT (r2 = −0.16, p = 0.06). In conclusion, based on the variability in pelvic tilt in this study population and the relatively small change in pelvic tilt following THA tilt-adjustment of the acetabular component position based on standing pre-operative imaging is likely to be of benefit in the majority of patients undergoing navigated THA. However, we have been unable to predict the relatively rare occurrence of a large change in pelvic tilt, which would confound tilt-adjusted component position.
