Prospective analysis of rural-urban differences in demographic patterns and outcomes following total joint replacement.

OBJECTIVE: Little is known about whether rural-urban differences exist in patients after hip and knee joint replacement surgery. We compared patient characteristics, pain and functional outcomes of rural and urban patients undergoing joint replacement surgery in a single high-volume metropolitan centre. DESIGN: Prospective cohort study conducted in patients who underwent primary elective hip (THJR) or knee replacement (TKJR) between 1 January 2006 and 31 December 2009. SETTING: A university-affiliated tertiary referral centre situated in the central metropolitan region of Melbourne, Australia. PARTICIPANTS: One thousand nine hundred fifty-five consecutive patients undergoing primary total joint replacement. MAIN OUTCOME MEASURE: Pain and function were assessed preoperatively and 12 and 24 months postoperatively. The main independent variable was geographic location specifically comparing patients residing in rural/regional compared with urban communities. RESULTS: A total of 2193 primary joint replacements were performed (981 THJR and 1212 TKJR) in 1955 patients. Rural patients presented at a younger age and with earlier radiographic disease than their urban counterparts. There was a higher rate of rheumatoid arthritis among rural patients presenting for TKJR. There was no difference in pain and function scores between groups at 12 and 24 months post-surgery. CONCLUSION: In our series of 1955 patients undergoing total hip and knee joint replacement surgery, rural patients presented at a younger age and an earlier stage of disease progression. At 24 months, rural patients had pain and functional outcomes as good as their urban counterparts. More research is required to determine which factors lead to the early presentation of rural patients.

Use of a fluoroscopy-based robotic-assisted total hip arthroplasty system resulted in greater improvements in hip-specific outcome measures at one-year compared to a CT-based robotic-assisted system.

BACKGROUND: The purpose of this study was to compare one-year patient reported outcome measures between a novel fluoroscopy-based robotic-assisted (FL-RTHA) system and an existing computerised tomography-based robotic assisted (CT-RTHA) system. METHODS: A review of 85 consecutive FL-RTHA and 125 consecutive CT-RTHA was conducted. Outcomes included one-year post-operative Veterans RAND-12 (VR-12) Physical (PCS)/Mental (MCS), Hip Disability and Osteoarthritis Outcome (HOOS) Pain/Physical Function (PS)/Joint replacement, and University of California Los Angeles (UCLA) Activity scores. RESULTS: The FL-RTHA cohort had lower pre-operative VR-12 PCS, HOOS Pain, HOOS-PS, HOOS-JR, and UCLA Activity scores compared with patients in the CT-RTHA cohort. The FL-RTHA cohort reported greater improvements in HOOS-PS scores (-41.54 vs. -36.55; p = 0.028) than the CT-RTHA cohort. Both cohorts experienced similar rates of major post-operative complications, and had similar radiographic outcomes. CONCLUSIONS: Use of the fluoroscopy-based robotic system resulted in greater improvements in HOOS-PS in one-year relative to the CT-based robotic technique.

Fluoroscopy-based robotics in total hip arthroplasty mitigates laterality-based differences in acetabular cup placement when compared to the manual, fluoroscopic- assisted technique.

BACKGROUND: Robotic assistance in total hip arthroplasty (RA-THA) has been shown to minimize laterality-based differences in acetabular cup positioning. OBJECTIVE: To determine if the use of a novel, fluoroscopy-based RA-THA system mitigates differences in acetabular cup placement between left (L) and right (R) side hip procedures, when compared to manual, fluoroscopic-assisted technique. METHODS: We conducted a retrospective review of 106 consecutive mTHA (40 L/66 R) and 102 RA-THA (48 L/54 R) primary direct anterior approach procedures. All cases were performed by a single right-hand-dominant surgeon, for a pre-operative diagnosis of osteoarthritis, avascular necrosis, or rheumatoid arthritis. Outcomes included acetabular cup inclination and anteversion, and the proportion of cups within the Lewinnek safe-zone. RESULTS: The average inclination of mTHA L cases was smaller than that of mTHA R cases (41.10∘± 7.38 vs. 43.97∘± 6.27; p= 0.04). For RA-THA, L and R cup angles were similar. There were fewer overall mTHA hips within the Lewinnek safe-zone compared to RA-THA (0.59 vs. 0.78; p= 0.003), as well as fewer mTHA R cases than RA-THA R cases (0.59 vs. 0.80; p= 0.03) within safe zone. CONCLUSION: Use of a novel, fluoroscopy-based robotic system mitigates laterality-based differences in acetabular cup placement that were observed in a manual, fluoroscopic-assisted cohort.

Comparison of CT with intra-operative navigation reported implant position utilising a robotic assisted technique in total knee arthroplasty.

BACKGROUND: Validation of navigated total knee arthroplasty (TKA) systems assists clinicians in making treatment decisions. The aim of this study was to independently review a navigation assisted robotic system for use in TKA. METHODS: We evaluated 87 patients (92 knees) undergoing robotic assisted TKA. Position estimated by the navigation software and postoperative CT scan were compared. Post-operative CT scans were interpreted by a senior radiologist blinded to intra-operative component position. Recorded were femoral varus/valgus, tibial varus/valgus and overall limb alignment in the coronal plane. In the sagittal plane tibial slope and femoral flexion/extension. Femoral component rotation was assessed in relation to the transepicondylar axis (TEA). RESULTS: Mean difference between software estimation and postoperative CT scan of the femoral component position in the coronal plane was 1.02° (0.86-1.18, 95%CI). Tibial coronal position was 1.19° (0.97-1.41). Sagittal plane component position for the femur was 1.64° (1.41-1.87). Tibial slope was 1.44° (1.21-1.68). Mean femoral component rotation was 1.27° (1.01-1.53). Overall 94.57% of intraoperative measures were within 3° of the component position measured on CT. CONCLUSION: Robotic assisted navigation used in combination with a novel balancing system can result in very accurate component positioning during total knee arthroplasty.

Water conservation in surgery: a comparison of two surgical scrub techniques demonstrating the amount of water saved using a 'taps on/taps off' technique.

OBJECTIVE: Australia finds itself in the grip of its worst drought on record. The surgical profession has a responsibility to conserve water where possible. We tried to show how much water we saved through the simple measure of turning taps off while not in use during the surgical scrub. DESIGN: We conducted a prospective analysis of two different scrub techniques at the Gold Coast Hospital in Queensland, Australia. Ten participants completed two 5-min scrubs using standard 'elbow on' taps. In the first, they left the taps running throughout the scrub; in the second, they turned the taps on and off so that water ran only when rinsing the hands. Water was collected and the amount of time the hands spent under running water was recorded. MAIN OUTCOME MEASURE: Amount of water used during the surgical scrub. RESULTS: A mean of 15.5 L was used during the 'taps on' scrub, with participants spending a mean of 47 s rinsing the hands. During the 'taps on/off' scrub, participants used a mean of 4.5 L, spending 40 s rinsing the hands. This represents a water saving of 11 L or 71% for each scrub (P < 0.001). There was a difference of 7 s in time rinsing the hands (P = 0.16). CONCLUSION: A taps on/off technique is a simple and effective way of conserving large amounts of water during the surgical scrub. The technique should be adopted as standard practice.

Review of knee arthroscopic practice and coding at a major metropolitan centre.

BACKGROUND: Arthroscopic knee surgery has been a topic of significant controversy in recent orthopaedic literature. Multiple studies have used administrative (Victorian Admitted Episodes Dataset and Centre for Health Record Linkage) data to identify trends in practice. This study explored the usage and reporting of arthroscopic knee surgery by conducting a detailed audit at a major Victorian public hospital. METHODS: A database of orthopaedic procedures at St Vincent's Hospital Melbourne was used to retrospectively identify cases of knee arthroscopy from 1 December 2011 to 1 April 2014. Procedures were categorized as diagnostic or interventional, and native and prosthetic joints were analysed separately. Procedure codes were reviewed by comparing a registrar, auditor and hospital coders for agreement. RESULTS: Of the 401 cases for analysis, 375 were conducted in native knees and 26 in prosthetic joints. Of native knees, 369 (98.4%) were considered interventional. The majority of these were conducted for meniscal pathology (n = 263, 70.1%), osteoarthritis (OA) (n = 25, 6.7%) and infection (n = 28, 7.6%). Comparison of codes assigned by different parties were found to be between 57% (k = 0.324) and 70% (k = 0.572) agreement, but not statistically significant. CONCLUSIONS: In this study, the most common indication for arthroscopy was meniscal pathology. Arthroscopy was rarely performed for OA in the absence of meniscal pathology. Diagnostic arthroscopy was rarely performed in the native knee, and fair to moderate agreement existed between parties in assigning Medicare Benefits Schedule procedure codes.

The Immediate Post-Operative Radiograph is an Unreliable Measure of Coronal Plane Alignment in Total Knee Replacement.

BACKGROUND: Restoration of a neutral mechanical axis is a primary goal of total knee replacement (TKR). A mechanical axis within 3° of neutral has been correlated with improved implant longevity, function, and patient satisfaction. We hypothesize that the immediate post-operative radiograph is an unreliable method of measuring alignment following TKR surgery. METHODS: Seventy-five consecutive patients had supine X-rays performed on day two post-operatively followed by standing long-leg radiographs (LLRs) 6 weeks post-operatively. Correlation was sought between the mechanical axis measured on the LLR and surrogate markers of alignment on the post-operative X-ray including component alignment and an estimation of anatomical alignment using the available length of femoral and tibial shafts. Inter- and intra-observer reliabilities were assessed. RESULTS: The mean mechanical axis on the LLR was 180.5 (SD 3.0, range 175.1-187.1). Mean offset between anatomical axis and mechanical axis was 6.4°. The mean anatomical axis measured on the short-leg X-ray was 174.9 (SD 2.4, range 169.5-181.3). Mechanical axis on the LLR was compared to the anatomical axis measured on the short-leg radiograph (SLR) + 6° with an interclass correlation coefficient of 0.588 (p < 0.001). The level of disagreement between the short- and long-leg X-rays was assessed using the Bland-Altman method and demonstrated clinically important discrepancies of 5 or more degrees in 9% of cases. Inter- and intra-observer agreements were high on all measures (p < 0.001). CONCLUSION: The long-leg weight bearing X-ray is an essential tool to accurately assess coronal plane alignment post TKR. While the immediate post-operative X-ray taken supine provides useful information to the surgeon on any immediate complications, our results indicate that it cannot be relied upon to determine correct restoration of the mechanical axis.