INTRODUCTION. The direct anterior approach (DAA) for total hip arthroplasty has become a popular technique. Proponents of the anterior approach cite advantages such as less muscle damage, lower dislocation risk, faster recovery, and more accurate implant placement for the approach. However, there is a steep, complex learning curve associated with the technique. The present study seeks to define the learning curve based on individual surgical and outcome variables for a high-volume surgeon. METHODS. 300 consecutive patients were retrospectively analyzed. Intraoperative outcomes measured include surgery time and estimated blood loss (EBL). Complications include intraoperative fracture, post-operative fracture, infection, dislocation, leg length discrepancy, loosening, and medical complications such as deep vein thrombosis (DVT) and pulmonary embolism (PE). Segmented regression models were used to elucidate the presence of a learning curve and mastery of the procedure with regard to each individual variable. RESULTS. The mean operative time was 77.1 minutes (range 40–213). Operative time improved at a rate of 6.6 minutes per case for the first 15 cases then by an average of 5 seconds per subsequent case. The mean EBL for the series was 288.6 mL. Segmented regression shows EBL decreased at a rapid rate until case 52, followed by a more gradual decline. Complications were higher in the first 7 surgeries, with a 48% decrease in the likelihood of complication with each subsequent surgery. The improvement continued through the rest of the series with a 0.5% decrease in likelihood with each surgery. DISCUSSION. Our data contributes to the current body of literature by defining the learning curve with what we consider the most pertinent outcomes. First, we show that operative efficiency can be gained quite quickly (15 cases) while the slower improvement in EBL demonstrates continued learning about the anatomy. Our data is consistent with previous published reports regarding complication improvement. The present study will provide surgeons considering DAA useful information regarding what to expect during their learning curve. Furthermore, the data can be useful for surgeons charged with teaching the technique to critically evaluate what learning curve variables can be improved to hasten the learning curve

Source of the study: University of Auckland, Auckland, New Zealand. Unicompartmental knee arthroplasty (UKA) has benefits for patients with appropriate indications. However, UKA has a higher risk of revision, particularly for low-usage surgeons. The introduction of robotic-arm assisted systems may allow for improved outcomes but is also associated with a learning curve. We aimed to characterise the learning curve of a robotic-arm assisted system (MAKO) for UKA in terms of operative time, limb alignment, component sizing, and patient outcomes. Operative times, pre- and post-surgical limb alignments, and component sizing were prospectively recorded for consecutive cases of primary medial UKA between 2017 and 2021 (n=152, 5 surgeons). Patient outcomes were captured with the Oxford Knee Score (OKS), EuroQol-5D (EQ-5D), Forgotten Joint Score (FJS-12) and re-operation events up to two years post-UKA. A Cumulative Summation (CUSUM) method was used to estimate learning curves and to distinguish between learning and proficiency phases. Introduction of the system had a learning curve of 11 cases. There was increased operative time of 13 minutes between learning and proficiency phases (learning 98 mins vs. proficiency 85 mins; p<0.001), associated with navigation registration and bone preparation/cutting. A learning curve was also found with polyethylene insert sizing (p=0.03). No difference in patient outcomes between the two phases were detected for patient-reported outcome measures, implant survival (both phases 98%; NS) or re-operation (learning 100% vs. proficiency: 96%; NS). Implant survival and re-operation rates did not differ between low and high usage surgeons (cut-off of 12 UKAs per year). Introduction of the robotic-arm assisted system for UKA led to increased operative times for navigation registration and bone preparation, but no differences were detected in terms of component placement or patient outcomes regardless of usage. The short learning curve regardless of UKA usage indicated that robotic-arm assisted UKA may be particularly useful for low-usage surgeons

The introduction of robotics for total knee arthroplasty (TKA) into the operating theatre is often associated with a learning curve and is potentially associated with additional complications. The purpose of this study was to determine the learning curve of robotic-assisted (RA) TKA within a multi-surgeon team. This prospective cohort study included 83 consecutive conventional jig-based TKAs compared with 53 RA TKAs using the Robotic Surgical Assistant (ROSA) system (Zimmer Biomet, Warsaw, Indiana, USA) for knee osteoarthritis performed by three high-volume (> 100 TKA per year) orthopaedic surgeons. Baseline characteristics including age, BMI, sex and pre-operative Kellgren-Lawrence grade were well-matched between the conventional and RA TKA groups. Cumulative summation (CUSUM) analysis was used to assess learning curves for operative times for each surgeon. Peri-operative and delayed complications were reviewed. The CUSUM analysis for operative time demonstrated an inflexion point after 5, 6 and 15 cases for each of the three surgeons, or 8.7 cases on average. There were no significant differences (p = 0.53) in operative times between the RA TKA learning (before inflexion point) and proficiency (after inflexion point) phases. Similarly, the operative times of the RA TKA group did not differ significantly (p = 0.92) from the conventional TKA group. There was no discernible learning curve for the accuracy of component planning using the RA TKA system. The average length of post-operative follow-up was 21.3 ± 9.0 months. There was no significant difference (p > 0.99) in post-operative complication rates between the groups. The introduction of the RA TKA system was associated with a learning curve for operative time of 8.7 cases. Operative times between the RA TKA and conventional TKA group were similar. The short learning curve implies this RA TKA system can be adopted relatively quickly into a surgical team with minimal risks to patients

Background. Several recent reports have documented high frequency of malpositioned acetabular components, even amongst high volume arthroplasty surgeons. Robotic assisted total hip arthroplasty (THA) has the potential to improve component positioning; however, to our knowledge there are no reports examining the learning curve during the adoption of robotic assisted THA. Purpose. The purpose of this study was to examine the learning curve of robotic assisted THA as measured by component position, operative time, intra-operative technical problems, and complications. Methods. The first 105 robotic-assisted THAs performed by a single surgeon with a posterior approach from June 2011 to August 2013 patients were divided into three groups based on the order of surgery. Group A was cases 1–35, group B 36–70 and group C 71–105. Component position, operative time, intra-operative technical problems, and intra-operative complications were recorded. Results. There was no significant difference between groups A, B, and C for BMI or age (Figure 1). Gender was different between groups with 20 males in group A, 9 in group B, and 16 in group C (p < 0.05). There was no difference for mean acetabular inclination, acetabular anteversion, or leg length discrepancy between groups as experience increased (p > 0.05) (Figure 2). The average operative time for groups A, B, and C was 79.8 ± 27 min, 63.2 ± 14.2 min, and 69.4 ± 16.3 min respectively (p = 0.02). The cumulative number of outliers was two for the Lewenick safe zone and six for the Callanan safe zone. Figure 3 displays acetabular component positioning in relation to previously documented safe zones for the three groups. The risk of having an acetabular component outside of Lewenick's safe zone was not different between groups (p = 0.60). The risk of having an acetabular component outside of Callanan's safe zone decreased after group A and was statistically significant (p = 0.02). Overall there were nine (9%) intra-operative technical problems and complications. In group A there were three complications: one loosened femoral array, one loosened pelvic array, and one cup that appeared erroneous according to the navigation system. In group B there was one femoral calcar fracture treated with a cerclage wire, one loosened femoral array, and one intra-operative delay. In group C there were three technical problems, all a loosened femoral array. There was no difference in the overall number of intra-operative complications between groups (p = 1.0). Conclusion. A learning curve was observed, as a decreased incidence of acetabular component outliers and decreased operative time were noted with increased experience. Satisfactory acetabular component positioning and leg length matching were found throughout the learning curve of robotic assisted total hip arthroplasty, with very few outliers in either category. Based on these findings, we conclude that there is a learning curve of approximately 35 cases in robotic-assisted total hip arthroplasty

Introduction. Semi-active robots can improve the accuracy and precision of total knee arthroplasty (TKA). The surgical efficiency of the recently introduced NAVIO robotic-assisted (RA-TKA) surgery was assessed in this study to define: (1) the time commitment for RA-TKA; (2) the learning curve for RA-TKA; and (3) to compare RA-TKA surgical time commitment to conventional, instrumented TKA (CI-TKA). Materials and Methods. Beginning in May 2017, the first 100 patients undergoing NAVIO RA-TKA were registered pre-operatively. Operative time, defined as the time from surgical skin incision to capsular closure, was recorded. Exclusion criteria were cases in which surgical time was not recorded. During the same study period, surgical case times for fifty cases of CI-TKA procedures were also assessed. Baseline data, including age, gender, BMI, range of motion, was recorded for all subjects. Surgical and anesthetic technique, multi-modality pain management protocol, and post-operative mobilization was consistent for all patients enrolled in the study. Results. No cases were excluded due to missing data. Demographics were similar in the study groups. Average surgical time for the first 100 RA-TKA cases was 68.2 minutes (range 48–100 minutes). The learning curve, as defined by both absolute (added surgical time) and relative measures (percentage of added time) was forty cases. Significant further surgical efficiency was achieved after 80 cases. In comparison to CI-TKA (average surgical time 51.7 minutes), the first ten RA-TKA cases required an average of 80 minutes, or over 50% increase in surgical time. After case #40, RA-TKA took only 10 minutes longer (18% greater) than CI-TKA. After case #80, RA-TKA required less than 5% more time than RA-TKA. Discussion/Conclusions. The initial experience with the NAVIO RA-TKA produced predictable surgical efficiency as measured by surgical time commitment. The learning curve for this user was forty cases. After eighty cases, RA-TKA was time neutral (<5% added time). This study demonstrates that implementation of robotic-assisted technology in TKA can achieve a high level of surgical efficiency within an acceptable learning curve

Introduction. The FitBone lengthening nail (Orthofix UK) is an intramedullary device licensed for the lengthening of long bones in adults in the UK. It contains a motor powered by electricity transmitted via an induction coil placed underneath the skin. It was developed in Germany two decades ago but uptake in the UK has only started more recently. The aim of this study was to review the first cohort of FitBone lengthening nails in a unit with significant experience of other lengthening nails (including PRECICE and Stryde). Materials & Methods. Demographic, clinical and radiological data was prospectively collected on all FitBone cases starting in February 2022. Accuracy of lengthening rate, patient satisfaction and implant issues were all considered. Complications and learning points were recorded and discussed by the multidisciplinary team involved in the patients care. Results. Eleven lengthening nails were inserted between February and November 2022 (6 right femurs, 5 left femurs). The average patient age was 31 (16–57) with 4 females and 7 males. The average lengthening achieved was 44mm (13– 70) over an average of 59 days (35 to 104). Significant technical issues were encountered in this cohort of patients including slow opening up at osteotomy site (3 requiring speeding up of programme), early consolidation (one requiring re-do osteotomy) and backing out of locking screws (3 out of 11 nails). There were also patient use concerns with difficulty using the motor and the inability to reverse the lengthening without an additional component to the motor. Conclusions. We present the first UK cohort of patients with femoral lengthening using the FitBone implant and device. We highlight the technical and patient issues encountered during this learning curve and propose solutions to avoid these pitfalls

Previous research has shown that tunnel placement is critical in ACL reconstruction. The ultimate position of both the femoral and tibial tunnel determines knee kinematics and overall function of the knee post surgery. As with all techniques there is a definite learning curve for the arthroscopic technique. However, the effect of the learning curve on tunnel placement has been studied sparsely. The purpose of this project therefore is to investigate the effect of the learning curve on tunnel placement. Postoperative radiographs of the first 200 anterior cruciate reconstructions with bone-tendon-bone patella tendon of a single orthopaedic surgeon performed during the first four years of independent practice were analysed for tunnel placement. Radiographs were digitalised and imported into a CAD program. Tunnel placement both femoral and tibial antero-posterior and sagittal was assessed using Sommer's criteria. A rating scale was developed to assess overall placement. A total of 100 points indicated perfect placement. A maximum of 30 points each were allocated for sagittal femoral and tibial placement and a maximum of 20 points each were allocated for coronal placement. Tunnel placement scores improved from 66 for the first 25 procedures to 87 for the last 25 procedures. Sagittal femoral placement (zone 1–4 with zone 1 being the preferred zone of placement) improved from an average of 1.44 to 1.08. Sagittal tibial placement (45% from anterior border of tibia) did not change significantly and remained between 42.82 t0 44.76%. Coronal femoral placement (between 10:00–11:00 o'clock for the right knee and 1:00–2:00 for the left knee) ranged from 10.45–11.15 and 12:45-1:15 o'clock respectively. This finding may be related to the transtibial tibial technique used to place the femoral tunnel. Coronal tibial placement (45% from medial tibial border) ranged from 45-46.58%. Correct placement of the femoral and tibial bone tunnels is important for a successful reconstruction of the anterior cruciate ligament (ACL). This study demonstrated a definitive learning curve and steady improvement of tunnel placement. Whilst there was no significant improvement in sagittal placement, overall placement improved significantly

Introduction. Total knee arthroplasty (TKA) is a well established treatment option for patients with end stage osteoarthritis. Conventional TKA with manual instruments has been shown to be a cost effective and time efficient surgery. While robotic-assisted operative systems have been shown to have benefits in surgical accuracy, they have also been reported to have longer surgical times. The purpose of this work was to determine surgical time and learning curve for a novel robotic-assisted TKA platform. Methods. Eighty-five subjects underwent robotic-assisted TKA by one of three investigators as part of an FDA and IRB approved Investigational Device Exemption (IDE). All patients received a cruciate retaining total knee implant system. Intra-operative safety, Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Knee Society Scores (KSS) were collected pre-operatively and at three month follow-up. In addition, surgical times were collected as part of a TKA work flow. To identify activities related to surgical steps required for robotic procedures specific time stamps were determined from the system. Capture of the hip center to final bone cut was used to define case time and identify robotic learning curve. Descriptive statistics were used to analyze results. Results. Surgeon one completed 24 cases, surgeon two completed 32, and surgeon three completed 29 cases in the study. An average surgical time of 44 minutes with standard deviation of 15.7 minutes was recorded. On average surgeons improved in surgical time with increasing cases as indicated by linear regression results. During initial cases, surgeons repeated intra-operative planning steps which decreased with the learning curve. In addition, the average WOMAC score improvement from pre-operative to three months was 33.1 ± 20.04 (p<0.0001). The average KSS Knee score improvement was 46.12 ± 19.68 (p<0.0001). Subjects recovered their pre-operative range of motion by three months post-operative. Conclusion. With cost related pressures in healthcare, hospitals and surgeons focus on improvements in surgical efficiency to stay competitive. The results of this study indicated comparable operative times to conventional TKA cases as reported in literature with the added benefit of optimizing surgical accuracy. Robotic solutions in TKA may become increasingly efficient as surgeons complete a learning curve

Background. Minimally invasive surgery is being widely used in the field of total hip arthroplasty (THA). The advantages of the direct anterior approach (DAA), which is used in minimally invasive surgery, include low dislocation rate, quick recovery with less pain, and accuracy of prosthesis placement. However, minimally invasive surgery can result in more complications related to the learning curve. The aim of this study was to evaluate the learning curve of DAA-THA performed by a senior resident. Methods. Thirty-three consecutive patients (33 hips) who underwent primary THA were enrolled in this study. All operations were performed by a senior resident using DAA in the supine position without the traction table. The surgeon started using DAA exclusively for all cases of primary THA after being trained in this approach for 6 months. Operative time, intraoperative blood loss, complications, and accuracy of prosthesis placement were investigated. Results. The mean intraoperative blood loss was 524 mL (range, 130–1650 m L). The mean operative time was 60 min (range, 41–80 min). Radiographic analysis showed an average acetabular anteversion angle of 17.0±3.3°, abduction angle of 37.8±4.3°, and stem alignment of 0±0.8°. Thirty-two (97%) of 33 cups were placed within the Lewinnek's safe zone. The overall complication rate was 12% (4 of 33 hips), including 1 proximal femoral fracture (salvaged with circumferential wiring), 1 temporary femoral nerve palsy (completely recovered in 2 weeks), 1 stem subsidence (5 mm), and 1 cup migration. Three of these complications were occurred in the first 10 cases. No revision surgery was required, No postoperative dislocation occurred. Conclusion. We investigated the learning curve of DAA-THA performed by a senior resident. We considered the first 10 cases as the learning curve, but concluded that with adequate training this procedure can be performed safely and effectively without increasing the risk of complications

With the introduction of new technology in orthopaedics, surgeons must balance anticipated benefits in patient outcomes with challenges or complications associated with surgical learning curve for the technology. The purpose of this study was to determine whether surgeon learning curve with a new multi-radius primary TKA system and instruments designed to improve surgical team ease would impact clinical outcomes, surgical time, and complications. From November 2012 to July 2015, 2369 primary TKAs were prospectively enrolled in two multicentre studies across 50 sites in 14 countries with a new knee system (NEW-TKA) evenly balanced across four configurations: cruciate retaining or posterior stabilised with either fixed bearing or rotating platform (CRFB, CRRP, PSFB, PSRP). 2128 knees had a<1 year visit and 1189 had a minimum 1 year visit. These knees were compared to a reference dataset of 843 primary TKAs from three manufacturers in the same four configurations with currently available products (CA-TKA). Demographics for NEW-TKA and CA-TKA were similar and typical for primary TKA. Operative times, clinical outcomes and a series of five patient reported outcomes were compared for NEW-TKA vs. CA-TKA. The first 10 New-TKA subjects for each surgeon were defined as learning curve cases (N=520) and were compared to all later subjects (N=1849). Patient reported outcome measure and clinical outcome analyses were covariate adjusted for patient demographics, pre-op assessment and days post-op. Mean (SD) surgical time for NEW-TKA learning curve cases was 79.1 (24.3) minutes, which reduced thereafter to 73.6 (24.3) (p=0.002). Beyond 10 cases, there was a continued reduction in NEW-TKA surgical time (R-Squared = 0.031). After 10 cases, surgical time was on par with the mean (SD) 71.9 (21.6) for CA-TKA (p=0.078). PROM outcomes of the first 10 learning curve cases for NEW-TKA were not statistically different from later cases at less than 1 year or later when adjusted for relevant covariates including configuration, patient demographics, pre-op functional status, and time post-op (p-values > 0.01). PROM outcomes for NEW-TKA vs. CA-TKA under the same covariate adjustments showed a trend favoring KOOS ADL, Symptoms, and Sport and Recreation subscores at minimum 1 year (p-values < 0.01). The incidence of intraoperative operative site complications was 1.3% for the NEW-TKA learning curve cases which was similar to the 0.6% rate for historical CA-TKA (p=0.231) and the intraoperative complication rate for the NEW-TKA later cases was consistent with learning curve cases (p=0.158). The introduction of new implants into the market place needs to have adequate data to support that they are safe and effective. Except for a minor increase in surgical time during the first 10 patients, this study found that surgeon learning curve with this new primary TKA system does not adversely affect patient short term outcomes and complication rates

INTRODUCTION. The goal of the study was to perform quality control with a commercially available navigation system when introducing PST technique at our academic department. The learning curve was assessed by the Cumulative Sum (CUSUM) test. We hypothesized that the PST process for TKA was immediately under control after its introduction when analyzed with the CUSUM technique. MATERIAL AND METHODS. The first 50 TKAs implanted with the use of PST at an academic department were scheduled to enter in a prospective, observational study. All TKAs were implanted by an experienced, high volume senior consultant with high experience in knee navigation. PSTs were carefully positioned over the bone and articular surfaces to the best fit position, without any navigated information. Then the 3D femoral and tibia PSTs positioning were recorded. The surgical procedure was then completed following the routine navigated procedure with standard navigated templates. To assess the 3D positioning of each template individually and of both templates together as a surrogate of the final TKA positioning, one point was given for each item inside the target, giving a maximal femur and tibia scores of 4 points, and a maximal knee score of 8 points, when all items were fulfilled. Following dataset was used for CUSUM chart plotting: allowable slack = 0.5SD, acceptable limit score = 6 points for knee score and 2 points for femur and tibia scores. For each measurement Mx, two CUSUMs (upper and lower CUSUMs) were calculated. These sums were plotted against the rank of the observation i. A trend in the process results in a change in the slope of the CUSUM, whereas the values are expected to fluctuate around a horizontal line if the process is in control. The process was considered out of control if upper CUSUM or lower CUSUM is outside the acceptable deviation interval. RESULTS. The knee score was still out of control after the 20th case (fig. 1). Both femur (fig. 2) and tibia (fig. 3) scores were still out of control after the 20th case as well. The decision was taken to interrupt the study after the 20th case as the learning curve appeared unacceptably long in comparison to the routine navigated technique. DISCUSSION. The main result of this study is that introduction of PST in an academic center may involve a significant learning curve: the process remained out of control even after 20 procedures. The present results contradict the common belief that introduction of PSTs is easy and does not require special instruction. These results indicate that surgeons should have only a progressive confidence with the self-sitting of PSTs when introducing this technology. Introducing PSTs might involve a significant loss of accuracy, at least when comparing with a navigation controlled implantation. In conclusion, CUSUM analysis allows monitoring the learning curve when introducing PSTs for TKA in an academic department. There may be a significant learning curve to achieve the steady state of accuracy and obtain an acceptable alignment. The decision was taken to discontinue using PSTs for TKA. For any figures or tables, please contact the authors directly

Introduction. With the introduction of new technology in orthopaedics, surgeons must balance anticipated benefits in patient outcomes with challenges or complications associated with surgical learning curve for the technology. The purpose of this study was to determine whether the surgeon learning curve with a new multi-radius primary TKA system (primary TKA implant and instruments) designed for surgical team ease would impact clinical outcomes, surgical time and complications. Materials & Methods. From November 2012 to July 2015, 2369 primary TKAs were prospectively enrolled in two multicenter studies across 50 sites in 14 countries with a new knee system (ATTUNE®) evenly balanced across four configurations: cruciate retaining or posterior stabilised with either fixed bearing or rotating platform (CRFB, CRRP, PSFB, PSRP). 2261 knees had a <1 year visit and 1628 had a greater than 1 year visit. These knees were compared to a reference dataset of 845 primary TKAs from three manufacturers in the same four configurations with currently available products (CURRENT-TKA). Demographics for ATTUNE and CURRENT-TKA were similar and typical for primary TKA. Operative times, clinical outcomes and a series of five patient reported outcomes were compared for ATTUNE vs. CURRENT-TKA. The first 10 ATTUNE subjects for each surgeon were defined as learning curve cases (N=520) and were compared to all later subjects (N=1849) and also with the CURRENT-TKA cases (N=845). Patient reported outcome measures and clinical outcome analyses were adjusted for covariates including patient demographics, pre-op assessment and days post-op. Results. Mean (SD) surgical time for ATTUNE learning curve cases was 79.3 (24.7) minutes, which reduced thereafter to 73.6 (24.3) (p<0.001). Beyond 10 cases, there was a continued reduction in ATTUNE surgical time (R-Squared = 0.031). After 10 cases, surgical time was on par with the mean (SD) 72.0 (21.7) for CURRENT-TKA (p=0.097). PROM outcomes of the first 10 learning curve cases for ATTUNE were not statistically different from later cases at less than 1 year or later when adjusted for relevant covariates including configuration, patient demographics, pre-op functional status, and time post-op (p-values > 0.01). PROM outcomes for ATTUNE vs. CURRENT-TKA under the same covariate adjustments showed a trend favoring KOOS ADL, Symptoms, and Sport and Recreation subscores at minimum 1 year (p-values < 0.05). The incidence of intraoperative operative site (knee) complications was 1.3% (7/520) for the ATTUNE learning curve cases which was similar to both the 0.6% (5/845) rate for historical CURRENT-TKA (p=0.230) and the 0.8% (14/1849) intraoperative complication rate for the ATTUNE later cases (p=0.195). Discussion. The introduction of new implants into the market place needs to have adequate data to support that they are safe and effective. Except for a minor increase in surgical time during the first 10 patients, this study found that surgeon learning curve with the new ATTUNE primary TKA system does not adversely affect patient short term outcomes and complication rates

Unicondylar knee arthroplasty (UKA) is growing in popularity with an increase in utilisation. As a less invasive, bone preserving procedure suitable for knee osteoarthritic patients with intact cruciate ligaments and disease confined to one compartment of the knee joint. The long term survival of a UKA is dependent on many factors, including the accuracy of prosthesis implantation and soft tissue balance. Robotic assisted procedures are generally technically demanding, can increase the operation time and are associated with a learning curve. The learning curve for new technology is likely to be influenced by previous experience with similar technologies, the frequency of use and general experience performing the particular procedure. The purpose of this study was to determine the time to achievement of a steady state with regards to surgical time amongst surgeons using a novel hand held robotic device. This study examined consecutive UKA cases which used a robotic assistive device from five surgeons. The surgeons had each performed at least 15 surgeries each. Two of the surgeons had previous experience with another robotic assistive device for UKA. All of the surgeons had experience with conventional UKA. All of the surgeons have used navigation for other knee procedures within their hospital. The system uses image free navigation with infrared optical tracking with real time feedback. The handheld robotic assistive system for UKA is designed to enable precision of robotics in the hands of the surgeon. The number of surgeries required to reach ‘steady state’ surgical time was calculated as the point in which two consecutive cases were completed within the 95% confidence interval of the surgeon's ‘steady state’ time. The average surgical time (tracker placement to implant trial acceptance phase) from all surgeons across their first 15 cases was 56.8 minutes (surgical time range: 27–102 minutes). The average improvement was 46 minutes from slowest to quickest surgical times. The ‘cutting’ phase was reported as decreasing on average by 31 minutes. This clearly indicates the presence of a learning curve. The surgeons recorded a significant decrease in their surgical time where the most improvement was in the process of bone cutting (as opposed to landmark registration, condyle mapping and other preliminary or planning steps). There was a trend towards decreasing surgical time as case numbers increase for the group of five surgeons. On average it took 8 procedures (range 5–11) to reach a steady state surgical time. The average steady state surgical time was 50 minutes (range 37–55 minutes). In conclusion, the average operative time was comparable with clinical cases reported using other robotic assistive devices for UKA. All five surgeons using the novel handheld robotic-assisted orthopaedic system for UKA reported significant improvement in bone preparation and overall operative times within the first 15 cases performed, reaching a steady state in surgical times after a mean of 8 cases. Therefore, this novel handheld device has a similar learning curve to other devices on the market

INTRODUCTION. The patient-specific templates (PST) for total knee arthroplasty (TKA) have been developed to improve accuracy of implantation, decrease operating time and decrease costs. There remains controversy about the accuracy of PST in comparison with either navigated or conventional instruments. Furthermore, the learning curve after introducing PST has not been well defined. The goal of the present study was to perform quality control with a commercially available navigation system and the CUCUM test when introducing PST technique at our academic department. MATERIAL AND METHODS. The first 50 TKAs implanted with the use of PST at an academic department were scheduled to enter in a prospective, observational study. PSTs were designed to obtain a neutral coronal alignment. All TKAs were implanted by an experienced, high volume senior consultant with high experience in knee navigation. PSTs were carefully positioned over the bone and articular surfaces to the best fit position, without any navigated information. Then the 3D femoral and tibia PSTs positioning were recorded by the navigation system. The difference between expected and achieved position was calculated, and an accuracy score was calculated and plotted according to the rank of observation into a CUSUM test. RESULTS. There was no significant difference between the numerical values of femur plan and femur PST positioning for all four items. There was a significant difference between the numerical values of tibia plan and tibia PST positioning for all four items except the sagittal orientation. The knee score was still out of control after the 20th case. Both femur and tibia scores were still out of control after the 20th case as well. The decision was taken to interrupt the study after the 20th case as the learning curve appeared unacceptably long in comparison to the routine navigated technique. DISCUSSION. Introduction of PST in an academic centre may involve a significant learning curve: the process remained out of control even after 20 procedures. The present results contradict the common belief that introduction of PSTs is easy and does not require special instruction. These results indicate that surgeons should have only a progressive confidence with the self- sitting of PSTs when introducing this technology. The decision was taken to discontinue using PSTs for TKA

Background. Acetabulum positioning affects dislocation rates, component impingement, bearing surface wear rates, and need for revision surgery. Novel techniques purport to improve the accuracy and precision of acetabular component position, but may come have significant learning curves. Our aim was to assess whether adopting robotic or fluoroscopic techniques improve acetabulum positioning compared to manual THA during the learning curve. Methods. Three types of THAs were compared in this retrospective cohort: 1) the first 100 fluoroscopically guided direct anterior THAs (fluoroscopic anterior, FA) done by a posterior surgeon learning the anterior approach, 2) the first 100 robotic assisted posterior THAs done by a surgeon learning robotic assisted surgery (robotic posterior, RP) and 3) the last 100 manual posterior THAs done by each surgeon (total 200 THAs) prior to adoption of novel techniques (manual posterior, MP). Component position was measured on plain radiographs. Radiographic measurements were done by two blinded observers. The percentage of hips within the surgeons' target zone (inclination 30°–50°, anteversion 10°–30°) was calculated, along with the percentage within the safe zone of Lewinnek (inclination 30°–50°; anteversion 5°–25°) and Callanan (inclination 30°–45°; anteversion 5°–25°). Relative risk and absolute risk reduction were calculated. Variances (square of the SDs) were used to describe the variability of cup position. Results. 76% of MP THAs were within the surgeons' target zone compared with 84% of FA THAs and 97% of RP THAs. This difference was statistically significant, associated with a relative risk reduction of 87% (RR 0.13 [0.04–0.40], p<.01, ARR 21%, NNT 5) for RP compared to MP THAs. Compared to FA THAs, RP THAs were associated with a relative risk reduction of 81% (RR 0.19 [0.06–0.62], p<.01, ARR 13%, NNT 8). Variances were lower for acetabulum inclination and anteversion in RP THAs (14.0 and 19.5) as compared to the MP (37.5 and 56.3) and FA (24.5 and 54.6) groups. These differences were statistically significant (P<.01). Conclusion. Adoption of robotic techniques delivers significant and immediate improvement in the precision of acetabular component positioning during the learning curve. While fluoroscopy has been shown to be beneficial with experience, a learning curve exists before precision improves significantly

Introduction. There is increasing pressure on healthcare providers to demonstrate competitiveness in quality, patient outcomes and cost. Robotic and computer-assisted total knee arthroplasty (TKA) have been shown to be more accurate than conventional TKA, thereby potentially improving quality and outcomes, however these technologies are usually associated with longer procedural times and higher costs for hospitals. The aim of this study was to determine the surgical efficiency, learning curve and early patient satisfaction of robotic-assisted TKA with a contemporary imageless system. Methods. The first 29 robotic-assisted TKA cases performed by a single surgeon having no prior experience with computer or robotic-assisted TKA were reviewed. System time stamps were extracted from computer surgical reports to determine the time taken from the first step in the anatomical registration process, the hip center acquisition, to the end of the last bone resection, the validation of the proximal tibial resection. Additional time metrics included: a) array attachment, b) anatomical registration, c) robotic-assisted femoral resection, d) tibial resection, e) trailing, f) implant insertion, and skin-to-skin time. The Residual Time was also calculated as the skin-to-skin time minus the time taken for steps a) to f), representing the time spent on all other steps of the procedure. Patients completed surveys at 3 months to determine their overall satisfaction with their surgical joint. Results. All time metrics decreased significantly after the first 7 cases, except the residual time (table 1 and figure 1). Mean skin-to-skin time significantly decreased from 83.7min to 57.1min (p=0.0008) beyond 7 cases, and hip center to final cut validation time decreased from 30.2min to 20.3min (p=0.0002). 85.7% (24/29) of patients were “Fully satisfied” and 14.3% (5/29) were “Partly satisfied”. Cost analysis showed there were no capital costs associated with acquisition of the robotic system and per case cost was equal to conventional TKA. Conclusion. Improvements in surgical efficiency and quality are becoming increasing important in today's healthcare environment. The results of this study indicated equal cost, a short learning curve and comparable procedure times to conventional TKA. The Patient Reported Outcomes with this group of patients was very high compared to rates reported in the literature

Introduction. An appropriate positioning of a total knee replacement (TKR) is a prerequisite for a good functional outcome and a prolonged survival. Navigation systems may facilitate this proper positioning. Patient specific templates have been developed to achieve at least the same accuracy than conventional instruments at a lower cost. We hypothesised that there was no learning curve at our academic department when using patient specific templates for TKR instead of the routinely used navigation system. Material. The first 20 patients operated on for TKR at our academic department using a patient specific template entered the study. All patients had a pre-operative CT-scan planning with a dedicated software. The patient specific templates were positioned on the bone according to the best fit technique. The position of the templates was controlled at each step of the procedure by the navigation system, and eventually corrected to achieve the expected goal. The discrepancy between the initial and the final positioning was recorded. The paired difference between each set of measurement was analysed with appropriate statistical tests at a 0.05 level of significance. Results. The mean difference between the initial positioning of the tibia template in the coronal plane was 3° ± 4° (p<0.01); 5/10 cases were off the expected range. The mean difference between the initial positioning of the tibia template in the sagittal plane was 4° ± 3° (p<0.001); 6/10 cases were off the expected range. The mean difference between the initial positioning of the femur template in the coronal plane was 2° ± 2° (p<0.01); 3/10 cases were off the expected range. The mean difference between the initial positioning of the tibia template in the sagittal plane was 3° ± 3° (p<0.01); 4/10 cases were off the expected range. After correction of the position according to the navigation system, all templates were placed in the expected range in all directions. There was a trend to improve the initial positioning of the templates at the end of the study, especially for the femoral template. Discussion. The global accuracy of the system tested was less than the navigated reference. The current system should not be used without extensive intra-operative control of the positioning of the templates. However, when the positioning of the templates was adequate, the orientation of the resection was correct. We conclude that the planning and manufacturing process may be adequate, but the question of the intra-operative positioning should be addressed. As the results about positioning improved during the time of the study, one might argue that one of the relevant question is the learning curve of the surgeon when using such templates

Introduction. Motion analysis is a validated method of assessing technical dexterity within surgical skills centers. A more accessible and cost-effective method of skills assessment is to use a global rating scale (GRS). We aimed to perform a validation experiment to compare an arthroscopic GRS against motion analysis for monitoring orthopaedic trainees learning simulated arthroscopic meniscal repairs. Methods. An arthroscopic meniscal repair task on a knee simulator was set up in a bioskills laboratory. Nineteen orthopaedic trainees with no experience of meniscal repair were recruited and their performance assessed whilst undertaking a standardized meniscal repair on 12 occasions. An arthroscopic GRS, assessing parameters such as “depth perception,” “bimanual dexterity,” “instrument handling,” and “final product analysis” was used to evaluate technical skill. Performance was assessed blindly by watching video recordings of the arthroscopic tasks. Dexterity analysis was performed using a motion analysis tracking system which measured “time taken,” “total path length of the subject's hands,” and “number of hand movements”. Results. Motion analysis objectively defined the learning curves and demonstrated significant improvement in performance over the 12 tasks (p< 0.0001). The GRS demonstrated the same learning curve with a significant improvement in performance (p< 0.0001). Importantly, for each individual subject, there was significant improvement in performance as assessed by GRS over the 12 tasks (p< 0.0001). There was a moderate correlation (p< 0.0001) between GRS and all the motion analysis parameters (r values: time=−0.58, path length=−0.58, hand movements=−0.51). Conclusion. Established arthroscopic GRSs have not previously been used to monitor learning curves during complex arthroscopic tasks. The results demonstrate that both the GRS and motion analysis are able to detect performance improvement during such tasks. This further validates the arthroscopic GRS for use in monitoring individual trainees and has the advantage over motion analysis of being directly transferrable to the operating room

Background:. The direct anterior approach (DAA) is one of the muscle sparing approaches in total hip arthroplasty (THA). The advantages of the DAA-THA include low dislocation rate, quick recovery with less pain, and accurate implantation. However, complications related to the learning curve have been reported. The aim of this study was to analyze the first 100 cases of DAA-THA performed by 2 surgeons. Methods:. The records of first 100 consecutive primary DAA-THAs performed by 2 orthopedic surgeons who have np experience of DAA-THA previously were retrospectively reviewed. All operations were performed using DAA in the supine position without the special traction table. The surgical result, the early clinical results, complications, and accuracy of prosthesis placement were investigated. Results:. The mean intraoperative blood loss was 424 ± 216 m. The mean operative time was 55.4 ± 17.5 minutes. One-hundred and ninety-one cups (96%) were placed within the Lewinnek's safe zone. The overall complication rate was 6% (12 hips), including 5 proximal femoral fracture, 3 stem subsidence, 2 temporal femoral nerve palsy, and 2 cup migration. No revision surgery was required, No postoperative dislocation occurred. Conclusion:. We analyzed the first 100 cases of DAA-THA performed by 2 orthopedic surgeons. We concluded that with appropriate training this procedure can be performed safely and effectively without increasing the risk of complications

Introduction

Intramedullary lengthening devices have been in use in older children with closed /open growth plates with good success. This study aims to present the early experience of the FITBONE nail since withdrawal of the PRECICE nail.