Introduction. The acetabular cup should be properly oriented to prevent dislocation and to reduce wear and leg length discrepancy. Despite advances in surgical techniques and instrumentation, achieving proper cup placement in total hip arthroplasty (THA) is challenging with potentially large variations of cup position and limited accuracy. We evaluated whether cup placement on anatomical location ensured original center of rotation (COR) and surgeon's experiences of THA reduced variations in acetabular component positioning. Methods. We retrospectively reviewed 145 patients (145 hips) of unilateral THAs with normal contralateral structures of acetabulum and femoral head. All surgeries were performed using the modified posterolateral approach that preserves short external rotator muscles. All of the 145 THAs were performed by two surgeons, who were in the same teaching hospital, but had differences in surgical experience and expertise for THA. The patients were divided into two groups based upon surgical experience: (1) the highly experienced surgeon's group: who had previously performed over 1000 THAs (YSK, 101 hips), and (2) the less experienced novice's group: who had performed fewer than 30 THAs (YWL, 44 hips). Real vertical distances, from the COR to the inter-tear drop line, and the real horizontal distances, from the COR to the lateral wall of the tear drop, were measured preoperatively using picture archiving communication system (PACS) based precise method. Postoperative ones were measured and equalized by use of a magnification marker placed on preoperative plain radiographs. And cup inclination was measured directly on the AP radiographs and anteversion was calculated by trigonometric functions. The patient's mean age was 52.1 years (range, 20–86). Results. The difference between preoperative and postoperative vertical distances of COR was mean 2.8±2.6 (range. −3.1–9.9) for the surgeon groups combined; it was mean 2.5±2.3 (range, −2.6–7.4) for the highly experienced surgeon and mean 3.7±2.9 (range, −3.1–9.9) for the less experienced surgeon(P = 0.009). The difference of horizontal distances of COR was mean 2.6±2.9 for the surgeon groups combined; it was mean 2.5±2.7 (range, −3.9–9.1) for the highly experienced surgeon and 2.8±3.3 (range, −2.8–10.2) for the less experienced surgeon(P = 0.87). The cup inclination was mean 43.4±7.6 (27.2–60.4) for the surgeon groups combined; it was mean 40.7±6.4 (range, 27.2–56.5) for the highly experienced surgeon and mean 49.4±6.5 (range, 29.2–60.4) for the less experienced surgeon (P = 0.001). The radiologic anteversion was mean 16.1±6.5 (range, 3.7–34.3) for the surgeon groups combined; it was mean 15.7±6.1 (range, 3.7–32.4) for the highly experienced surgeon and 17.2±7.2 (range, 5.1–34.33) for the less experienced surgeon (P = 0.194). 3 hips (7%) were dislocated in the novice's group, whereas none from the expert's group was dislocated. Discussion. In spite of the effort to restore anatomical COR, the cup COR tends to be located superiorly and medially compared to the original COR due to the influence of acetabular component and intended medialization of cup placement. Nevertheless, our findings suggest that a surgical experience could reduce variations in acetabular component positioning

Background. The current literature tends to suggest that all the different approaches used for Knee Arthroplasty give similar results. The literature also cautions that the MINI quadriceps sparing approaches are to be utilized in very select cases as they are difficult to perform, take longer time, have a greater intra-op complication rate and are associated with a higher number of component malpositioning. Despite these warnings of the literature, the author has been impressed by the physiological nature of the subvastus approach for knee arthrotomy and the author has used this approach exclusively for all Knee arthroplasties in the last 4 years. All primary Knee Arthroplasties have been performed through the mini-subvastus approach, utilizing the principle of a mobile window, irrespective of the degree of pre-operative deformity, obesity, range of motion or previous surgery. All revision Knee Arthroplasties have also been performed through the subvastus approach. All the surgeries have been performed in the private sector in a highly competitive environment with the patient having easy access to various other high volume surgeons performing arthroplasties through a more standard approach. Aim. To define the place of the subvastus approach in Knee arthroplasty on the basis of surgical experience gained after 1350 consecutive surgeries. Materials and Methods. All knees operated between Nov. 2005 to may 2010 are included in this study and have been prospectively evaluated by American Knee Society Scores. Pre and post-operative radiographs have been obtained in all. Additionally a significant number of knees have had pre and post-operative scanograms and skyline views taken. Surgical technique has involved the subvastus approach in all cases. The first 130 knees have been performed with the tourniquet and the remaining have been performed without a tourniquet but with the use of tranexamic acid peri-operatively. Surgical technique has evolved with the experience gained and would be discussed in detail. Computer navigation has been utilized to take the distal femoral cut in 110 knees. Intra and post-operative complications have been recorded. The author has used both CR and PS knees, mobile and fixed bearing, Gender specific and highflex knees with and without patellar resurfacing. The patients have been followed up at 6 weeks, 3 months and yearly. Results. The American Knee Society scores have improved significantly in the follow-up period. The post-operative radiographs have shown good alignment in more than 99% of knees. The Hospital stay has been reduced to 3 days and 95% of patients were able to independently ambulate with only a walking stick by the third day without any quadriceps lag. There have been 3 vascular injuries, 1 medial collateral injury, 2 patellar tendon ruptures, 3 periprosthetic fractures and 7 infections of these 1350 knees (complication rate 1.5%.) There are 2 knees awaiting surgery for limb malalignment. The results in various types of knees are similar but the PS knees have achieved a higher degree of post-op knee flexion more easily. Conclusions. The results obtained by this method are comparable if not better than the results obtained in other large series using more traditional approaches. The complication rate is similar but the patient recovery is much quicker. The approach is versatile, has wide applications and remains our approach of choice

Introduction

Malpositioning of the tibial component is a common error in TKR. In theory, placement of the tibial tray could be improved by optimization of its design to more closely match anatomic features of the proximal tibia with the motion axis of the knee joint. However, the inherent variability of tibial anatomy and the size increments required for a non-custom implant system may lead to minimal benefit, despite the increased cost and size of inventory.

This study was undertaken to test the hypotheses: 1.

That correct placement of the tibial component is influenced by the design of the implant.

Introduction. With advances in mobile application, digital health is being increasingly used for remote and personalised care. Patient education, self-management and tele communication is a crucial factor in optimising outcomes. Aims. We explore the use of a smartphone app based orthopaedic care management system to deliver personalised surgical experience, monitor patient engagement and functional outcomes of patients undergoing knee arthroplasty. Results. Over a 12-month period, 124 patients listed for knee arthroplasty were offered access to the app. Average patient age was 65.4 years (range 49 to 86). 13(10.4%) patients were over 80 years. Compliance with app usage was 86.4%. Compliance with post-operative exercises increased following a message through the app. The mean Oxford knee score improved from a pre-op value of 17 to 35 at a mean follow-up of 6 months. Mean numeric rating scale pain score reduced from 7 pre-operatively to 3 at the latest follow-up. 58 patients (46.7%) used the communication feature on the app (text messages, photos, video consultations), reducing telephone calls and patient foot fall in the hospital. Patient satisfaction with the app was very high. Conclusion. We found the virtual care system to be effective in providing patient education, prehabilitation and post-operative rehabilitation along with being an effective channel of communication between patients and the hospital team. Patient satisfaction and compliance was very high

The Australia and New Zealand Sarcoma Association established the Sarcoma Guidelines Working Party to develop national guidelines for the management of Sarcoma. We asked whether surgery at a specialised centre improves outcomes. A systematic review was performed of all available evidence pertaining to paediatric or adult patients treated for bone or soft tissue sarcoma at a specialised centre compared with non-specialised centres. Outcomes assessed included local control, limb salvage rate, 30-day and 90-day surgical mortality, and overall survival. Definitive surgical management at a specialised sarcoma centre improves local control as defined by margin negative surgery, local or locoregional recurrence, and local recurrence free survival. Limb conservation rates are higher at specialised centres, due in part to the depth of surgical experience and immediate availability of multidisciplinary and multimodal therapy. A statistically significant correlation did not exist for 30-day and 90-day mortality between specialised centres and non-specialised centres. The literature is consistent with improved survival when definitive surgical treatment is performed at a specialised sarcoma centre. Evidence-based recommendation: Patients with suspected sarcoma to be referred to a specialised sarcoma centre for surgical management to reduce the risk of local recurrence, surgical complication, and to improve limb conservation and survival. Practice point: Patients with suspected sarcoma should be referred to a specialised sarcoma centre early for management including planned biopsy

Aim. There is a constant increase of total joint arthroplasties to improve the quality of life of an aging population. Prosthetic-joint infections are rare, with an incidence of 1–2%, but they represent serious complications in terms of morbidity and mortality. Different therapeutic options exist, but the role of the surgeon's experience has never been investigated. The aim of this retrospective study is to assess the infection eradication success rate depending on the involvement of a septic surgeon. Method. Patients having a prosthetic-joint infection at Lausanne University Hospital (Switzerland) between 2006 and 2018 were included. The success rate depending on type of surgeon (septic vs non-septic) and type of surgical procedure was analyzed. Results. 444 patients (61% hips, 37% knees) were identified with a median age of 70 years. The overall success rate was 83% for septic surgeons compared to 61% for non-septic surgeons (p < 0.05). The effect of the surgeon was predominant in debridement with retention of the prosthesis where the experience could improve the success rate from 43% (non-septic) to 75% (septic) (p < 0.05). Conclusions. The involvement of a septic surgeon is associated with a significantly higher success rate, suggesting surgical experience is an important factor in treating prosthetic-joint infections

Introduction. Total hip arthroplasty (THA) is a commonly performed procedure to relieve arthritis or traumatic injury. However, implant failure can occur from implant loosening or crevice corrosion as a result of inadequate seating of the femoral head onto the stem during implantation. There is no consensus—either by manufacturers or by the surgical community—on what head/stem assembly procedure should be used to maximize modular junction stability. Furthermore, the role of “off-axis” loads—loads not aligned with the stem taper axis—during assembly may significantly affect modular junction stability, but has not been sufficiently evaluated. Objective. The objective of this study was to measure the three-dimensional (3D) head/stem assembly loads considering material choice—metal or ceramic—and the surgeon experience level. Methods. A total of 29 surgeons of varying levels (Attending, Fellow, Resident) were recruited and asked to perform a benchtop, head/stem assembly using an instrumented apparatus simulating a procedure in the operating room (Figure 1). The apparatus comprised of a 12/14 stem taper attached to a 3D load sensor (9347C, Kistler® USA, Amherst, NY). Surgeons were randomly assigned a metal or ceramic femoral head and instructed to assemble the taper using their preferred surgical technique. This procedure was repeated five times. Surgeons were brought back to test the opposite material after four weeks. Output 3D load data was analyzed for differences in peak vertical load applied, angle of deviation from the stem axis—termed off-axis angle, variability between trials, and impaction location. Results. Preliminary results suggest no significant differences between the loads applied to the metal heads and the ceramic heads. Across the two materials tested, both attendings and residents applied greater loads than fellows (p=0.33; Residents=9.0 kN vs Fellow=7.2 kN: p=0.27; Attendings=8.9 kN vs 7.2 kN) with significantly less variability (Attendings: σ= 1.58; Fellows: σ= 3.26; Residents: σ= 2.86). Attending surgeons also exhibited applied loads at significantly lower off-axis angles compared to fellows (p=0.01; 4.6° vs Fellow=7.2°) (Figure 2). However, all of our clinicians assembled ceramic head tapers with a greater off-axis angle as compared to assembling metal heads. In addition, metal heads were impacted more on-axis for all surgeon experience levels (Figure 3). While the impaction load plots suggest that the first impact strike is the most crucial for head stability, it was determined that the number of strikes is not as important as the maximum impaction load applied. Conclusion. Differences in impaction load when assembling metal and ceramic femoral heads were not apparent; however, variability of technique and load was observed across the different surgical experience levels as well as within surgeons of the same level. Understanding assembly mechanics and surgical habits for THA will provide insight to the best assembly procedures for these implants. For any figures or tables, please contact authors directly

Introduction. Total hip arthroplasty (THA) is a physically demanding procedure where the surgeon is subject to fatigue with increased energy expenditure comparable to exercise[1]. Robotic technologies have been introduced into operating rooms to assist surgeons with ergonomically challenging tasks and to reduce overall physical stress and fatigue[2]. Greater exposure to robotic assisted training may create efficiencies that may reduce energy expenditure[3]. The purpose of this study was to assess surgeon energy expenditure during THA and perceived mental and physical demand. Methods. 12 THAs (6 cadavers) randomized by BMI were performed by two surgeons with different robotic assisted experience. Surgeon 1 (S1) had performed over 20 robotic assisted THAs on live patients and Surgeon 2 (S2) had training on 1 cadaver with no patient experience. For each cadaver, laterality was randomized and manual total hip arthroplasty (MTHA) was performed first on one hip and robotic assisted total hip arthroplasty (RATHA) on the contralateral hip. A biometric shirt collected surgeon data on caloric energy expenditure (CEE) throughout acetabular reaming (AR) and acetabular implantation (AI) for each THA procedure. Surgeon mental and physical demand was assessed after each surgery. Scores were reported from 1–10, with 10 indicating high demand. A paired sample t-test was performed between MTHA and RATHA within each surgeon group with a confidence interval of (α =0.05). Results. Each surgeon demonstrated greater CEE during MTHA, Figure 1. Surgeon CEE during MTHA was greater for S1(100±28.1 cals) compared to RATHA(83.5±0.34 cals), with no significant difference (p>0.05, p=0.49). Energy expenditure was greater for S2 during MTHA(83.5±16.3 cals) compared to RATHA(75.3±0.71 cals) with no significance (p>0.05, p=0.68). RATHA resulted in a decrease in average CEE for each surgeon with a reduction of 16.5% for S1 and 9.8 % for S2. Surgeon task time during MTHA was greater for S1(14.7±3.2 mins) compared to RATHA(12.3±4.93 mins), with no significance (p>0.05, p=0.46). Average task time was greater for S2 during MTHA(10.0±2.65 mins) compared to RATHA(8.7±2.89 mins) with no significant differences (p>0.05, p=0.66). Average mental and physical demand was less for RATHA compared to MTHA, Figure 2. Average physical demand reported during AR for MTHA(5.5±1.2) was greater than RATHA(4.3±2.0, p=0.08). Average physical demand was greater for AI for MTHA(6±1.3) than RATHA(3.7±2.1, p=0.29). Average mental demand was significantly greater during AR for MTHA(5.7±1.03) when compared to RATHA(3.2±1.5, p=0.007). Average mental demand was greater during AI for MTHA(6.2±1.2) than RATHA(2.3±1.5, p=0.051). Conclusion. Regardless of prior surgical experience, both surgeons had reduced caloric expenditure when performing RATHA as compared to MTHA. For the surgeon with more RATHA experience, there was a greater percent reduction in caloric expenditure between surgical interventions. Both surgeons had similar percent reductions in time for RATHA compared to MTHA. Each surgeon noted increased mental and physical demand during MTHA. The trends suggest RATHA may reduce surgeon energy expenditure and time to perform acetabular reaming and implant insertion for THA. The pilot data suggests that there may be a relationship between energy expenditure and surgeon experience. This could be explored in future studies with a larger surgeon population. For any figures or tables, please contact the authors directly

Fifteen-year survivorships studies demonstrate that total knee replacements have excellent survivorship, with reports of 85 to 97%. However, excellent survivorship does not equate to excellent patient reported outcomes. Total knee imbalance with either too tight or loose soft tissues account for up to 54% of revisions in one series. This may account for many of the 20% unsatisfactory total knee arthroplasty outcomes. Soft tissue balancing technique is more like an art. The surgeon relies on subjective feel for appropriate ligamentous tension. Surgical experience and case volume play a major role in each surgeon's relative skill in balancing the knee properly. New technology of “smart trials” with embedded microelectronics and accelerometers, used in the knee with the medial retinaculum closed, can provide dynamic, intraoperative feedback regarding knee quantitative compartment pressures and component tracking. After all bone cuts are made using the surgeon's preferred techniques, trial components with the sensor tibial trial are inserted and the knee is taken through a passive range of motion. After visualizing the resultant compartment pressures and tracking data on a graphical interface, imbalance situations such as a too tight MCL or ITB, an incompetent or too tight PCL, or malrotated femoral or tibial component can be identified. A decision can be made as to whether to recut the bone to realign components, do a soft tissue release, or a combination of both. Soft tissue releases can be titrated while observing equalizing compartment pressures. Sensor feedback improves soft tissue balancing. More balanced compartments occur using a sensor trial than with standard soft tissue balancing technique blinded to sensor information. A multicenter three year study has shown that having the medial and lateral compartments in flexion and extension balanced within 15 pounds provides better outcomes. Patients with quantitatively balanced TKA with <15lbf mediolateral load differential have better forgotten knee scores at six weeks and six months. Use of smart trials is a new approach to total knee replacement surgery allowing fine tune balancing and takes soft tissue balancing from art to science

Background and aim. Since the market withdrawal of the ASR hip resurfacing in August 2010 because of a higher than expected revision rate as reported in the Australian Joint Replacement Registry (AOAJRR), metal-on-metal hip resurfacing arthroplasty (MoMHRA) has become a controversial procedure for hip replacement. Failures related to destructive adverse local tissue reactions to metal wear debris have further discredited MoMHRA. Longer term series from experienced resurfacing specialists however, demonstrated good outcomes with excellent 10-to-15-year survivorship in young and active men. These results have recently been confirmed for some MoMHRA designs in the AOAJRR. Besides, all hip replacement registries report significantly worse survivorship of total hip arthroplasty (THA) in patients under 50 compared to older ages. The aim of this study was to review MoMHRA survivorship from the national registries reporting on hip resurfacing and determine the risk factors for revision in the different registries. Methods. The latest annual reports from the AOAJRR, the National Joint Registry of England and Wales (NJR), the Swedish Hip Registry (SHR), the Finnish Arthroplasty Registry, the New Zealand Joint Registry and the Arthroplasty Registry of the Emilia-Romagna Region in Italy (RIPO) were reviewed for 10-year survivorship of MoMHRA in general and specific designs in particular. Other registries did not have enough hip resurfacing data or long term data yet. The survivorship data were compared to conventional THA in comparable age groups and determinants for success/failure such as gender, age, diagnosis, implant design and size and surgical experience were reviewed. Results. All registries showed a significant decline of the use of MoMHRA. The AOAJRR reported a cumulative revision rate of 9.5% (95%CI: 8.9–10.1%) at 10 years for all hip resurfacings. Female gender, developmental dysplasia and femoral head sizes <49mm were significant risk factors with revision rates twice as high for head sizes <49mm compared to >55mm. In males, cumulative revision rate for all MoMHRA was 6.6% at 10 years and 7.8% at 13years with no difference in the age groups. ASR had significantly higher revision rates (23.9% at 7 years) compared to other designs. The Adept and the Mitch had the lowest revision rates at 7 years (3.6%). Cumulative revision rates for 10,750 BHR (males and females pooled) were 5.0% at 7 years, 6.9% at 10years and 8.4% at 13 years. Cumulative revision rates of THA in patients <55 years was 6.0% at 10 years and 9.4% at 13 years. Similar survivorship results were found in the Finnish, Swedish, New Zealand and RIPO registry. In the SHR, 10-year survivorship of THA in patients <50 was only around 87%. In the NJR, cumulative revision rates for all MoMHRA pooled were much less favourable (13% at 10 years – 22% in patients<50) but the revision probability of ASR was 30.4% compared to 9.0% for BHR. Surgical experience was also identified as an important determinant of success/failure. Discussion. Registries are now confirming good 10-year survivorship of certain MoMHRA designs with excellent results in males. Risk factors for revision are female gender, small head size, dysplasia and certain implant designs

Background. Reasons for revision of metal-on-metal hip resurfacing arthroplasty (MoMHRA) have evolved with improving surgical experience and techniques. Early revisions were often due to fracture of the femoral neck while later revisions are associated with loosening and/or adverse local tissue reactions (ALTR) to wear debris. In some studies, revisions of MoMHRA with ALTR have been complicated by an increased risk of rerevision and poor outcome. The purpose of this study was to investigate the causes of failure and to identify factors that improve outcome following revision of a failed HRA. Methods. From 2001 to May 2015, 180 consecutive HRA revisions were performed in 172 patients. Ninety-nine primary surgeries were done at a HRA specialist centre (99/4211, revision rate: 2.4%), 81 elsewhere. Eight different HRA designs were revised mainly in females (60%). Components’ orientation was measured from radiographs using EBRA. Ion levels were used as a diagnostic tool since 2006 (n=153). Harris-Hip-Score (HHS) was obtained prerevision and at latest follow-up. The initial experience of the first 42 cases (Initial Group) was compared to cases 43–180 (Later Group). Patients of the Later group were noted to have less soft tissue damage, had significantly bigger THA heads implanted at surgery, were educated of the increased complication risk and some wore an abduction brace for 6 weeks. Results. All patients presented with some pain/discomfort. Mean time to revision was 38 months (0–160). Eight HRAs were revised for fracture and 8 for infection. The most common reason for revision was component malpositioning (acetabular 48%, excessive abduction and/or anteversion; femoral 10%) usually associated with high metal ions (62%). The most common intra-operative finding was ALTR (48%) followed by metallosis (36%) and impingement (29%). Metal sensitivity was suspected in 8 patients (6F/2M). There were gender-specific differences in component sizes and causes of failure, with a higher incidence of component malpositioning, osteolysis and elevated metal ions in women. Time to revision in patients with high metal ion levels was shorter with the ASR (21 months, SD:10) in comparison to the BHR (38 months, SD: 25) (p=0.05). For the whole cohort, HHS significantly improved post revision (93, 42–100) (p<0.001). Fourteen complications (9 dislocations; 5 infections) and 9 re-revisions occurred. Outcome {HHSpost-op (p=0.04), complication and re-revision rates (p=0.005)} was significantly better in the Later Group compared to the Initial group. The incidence of complications/re-revisions significantly reduced since the introduction of metal ions (p=0.004). The presence of ALTR did not significantly affect outcome (p=0.65). However, patients with ALTR in the Later group (n=51) had significant reduced complication(p=0.005) and re-revision(p=0.016) rates in comparison to those in the Initial Group. Conclusion. Component malpositioning is the most common cause of HRA failure. Metal ion measurements are an excellent tool to detect wear at an early stage. The revision analysis highlights the importance of surgical experience, indications and prosthesis design. Use of ion levels, big THA-heads and patient education/compliance were identified as factors improving outcome following HRA revision. Patients with soft tissue reactions can have good outcome if operated prior to extensive soft tissue destruction

Implant selection in TKA remains highly variable. Surgeons consider pre-operative deformity, patient factors such as BMI and bone quality, surgical experience, retention or substitution for the PCL, type of articulation and polyethylene, cost, and fixation with or without cement. We have most frequently implanted the same implant for the majority of patients. This is based on the fact that multiple large series of TKAs have demonstrated that the most durable TKAs have been non-modular metal-backed tibial components, retention of the PCL, with a cemented all-polyethylene patellar component. Polymer wear must be addressed for long-term durability. One method for reducing polyethylene wear is eliminating modularity between a metal-backed tray and the articular bearing surface. This can be done with a metal-backed implant as with the IB-1, AGC, Vanguard Mono-lock, or with elimination of the metal backing via a one piece all-polyethylene tibial component. The all-polyethylene implants appear design and patient sensitive. We observed higher clinical failure rates in a flat-on-flat design. Other authors have observed improved survivorship with coronal dishing of the articular surfaces which centralises osseous stresses. All-polyethylene implants have promise in the future but require proven design and fixation design features

Aims

Global literature suggests that female surgical trainees have lower rates of independent operating (operative autonomy) than their male counterparts. The objective of this study was to identify any association between gender and lead/independent operating in speciality orthopaedic trainees within the UK national training programme.

Fifteen-year survivorship studies demonstrate that total knee replacements have excellent survivorship, with reports of 85 to 97%. However, excellent survivorship does not equate to excellent patient reported outcomes. Noble et al. reported that 14% of their patients were dissatisfied with their outcome with more than half expressing problems with routine activities of daily living. There is also a difference in the patient's subjective assessment of outcome and the surgeon's objective assessment. Dickstein et al. reported that a third of total knee patients were dissatisfied, even though the surgeons felt that their results were excellent. Most of the patients who report lower outcome scores do so because their expectations are not being fulfilled by the total knee replacement surgery. Perhaps this dissatisfaction is a result of subtle soft tissue imbalance that we have difficulty in assessing intra-operatively and post-operatively. Soft tissue balancing techniques still rely on subjective feel for appropriate ligamentous tension by the surgeon. Surgical experience and case volume play a major role in each surgeon's relative skill in balancing the knee properly. New technology of “smart trials” with embedded microelectronics and accelerometers, used in the knee with the medial retinaculum closed, can provide dynamic, intra-operative feedback regarding knee quantitative compartment pressures and component tracking. After all bone cuts are made using the surgeon's preferred techniques, trial components with the sensor tibial trial are inserted and the knee is taken through a passive range of motion. After visualizing the resultant compartment pressures and tracking data on a graphical interface, the surgeon can decide if compartment loading differences are greater than 15 pounds whether to perform a soft tissue balance or minor bone recuts. If soft tissue balancing is chosen, pressure data can indicate where to perform the release and allow the surgeon to assess the pressure changes as titrated soft tissue releases are performed. A multi-center study using smart trials has demonstrated dramatically better outcomes out to three years

Aims. This study was conducted to investigate the influence of surgical experience on the outcomes and component positioning of total knee arthroplasty (TKA). We compared the outcomes and component positioning of simultaneous bilateral TKAs performed by supervisors and trainee surgeons. Patients and Methods. A total of 20 patients (40 knees) who underwent simultaneous bilateral primary TKA using the same cruciate-retaining TKA system between 2011 and 2015 were included. The mean patient age was 76 years (range: 64 to 86 years). There were 2 males and 18 females. The first phase of the operation was performed on the knee that was more severely degenerated by one supervisor who had performed over 1000 TKAs. The other knee was operated on next by trainee surgeons who had performed less than 20 TKAs. The knees were categorized into two groups: those operated on by supervisors (group S) and those operated on by trainee surgeons (group T). Outcome measures included range of motion (ROM), Knee Score (KS), and Function Score (FS). We also evaluated operative time, alignment of the leg, and the orientation of components, which was determined on post-operative long-leg coronal films. Results. The mean pre-operative maximal flexion was 119.8° in group T and 114.8° in group S (p=0.548). The mean pre-operative KS was 47.5 in group T and 35.6 in group S (p<0.01). The mean operative time was 124.5 min in group T and 91.8 min in group S (p<0.01). The mean post-operative maximal flexion was 114.0° in group T and 113.0° in group S (p=0.967). The mean post-operative KS was 93.9 in group T and 92.9 in group S (p=0.978). There were no significant differences in the ROM and KS when comparing supervisor and trainee surgeons. The overall mean FS increased to 70 from 42. The varus angle of the mean coronal tibial component was −1.12° in group T and 1.12° in group S (p<0.01). The varus angle of the mean coronal femoral component was 0.24° in group T and 1.82° in group S (p=0.0447). The mean FTA was 172.7° in group T and 176.4° in group S (p<0.01). The mean HKA was 179.2° in group T and 182.9° in group S (p<0.01). Conclusions. Operative time was significantly longer for TKAs performed by trainee surgeons compared to those performed by supervisors. However, alignment for knees in the supervisor group were significantly more likely to be varus compared with those in the trainee group. This study showed no significant difference in ROM and KS between supervisors and trainee surgeons

Fifteen-year survivorship studies demonstrate that total knee replacements have excellent survivorship, with reports of 85% to 97%. However, excellent survivorship does not equate to excellent patient reported outcomes. Noble et al. reported that 14% of their patients were dissatisfied with their outcome with more than half expressing problems with routine activities of daily living. There is also a difference in the patient's subjective assessment of outcome and the surgeon's objective assessment. Dickstein et al. reported that a third of total knee patients were dissatisfied, even though the surgeons felt that their results were excellent. Most of the patients who report lower outcome scores due so because their expectations are not being fulfilled by the total knee replacement surgery. Perhaps this dissatisfaction is a result of subtle soft tissue imbalance that we have difficulty in assessing intra-operatively and post-operatively. Soft tissue balancing techniques still rely on subjective feel for appropriate ligamentous tension by the surgeon. Surgical experience and case volume play a major role in each surgeon's relative skill in balancing the knee properly. New technology of “smart trials” with embedded microelectronics and accelerometers, used in the knee with the medial retinaculum closed, can provide dynamic, intra-operative feedback regarding knee quantitative compartment pressures and component tracking. After all bone cuts are made using the surgeon's preferred techniques, trial components with the sensored tibial trial are inserted and the knee is taken through a passive range of motion. After visualizing the resultant compartment pressures and tracking data on a graphical interface, the surgeon can decide whether to perform a soft tissue balance or minor bone recuts. If soft tissue balancing is chosen, pressure data can indicate where to perform the release and allow the surgeon to assess the pressure changes as titrated soft tissue releases are performed. A multi-center study using smart trials has demonstrated dramatically better outcomes out to three years

Implant selection in TKA remains highly variable. Surgeons consider preoperative deformity, surgical experience, retention or substitution for the PCL, type of articulation and polyethylene, and fixation with or without cement. We have most frequently implanted the same implant for the majority of patients. This is based on the fact that multiple large series of TKA's have demonstrated that the most durable TKA's have been non-modular metal backed tibial components, retention of the PCL, with a cemented all poly patellar component. The debate of how to handle the PCL continues. In most studies at 10 years there is little reported difference. Second decade concerns usually result from polyethylene issues related to polymer wear. Sagittal “dishing” or ultracongruent implants may be a middle road that allow PCL release or resection and controlled kinematics offering improved short term results. Long term function remains the goal and it appears a CR knee offers that capacity. Newer implants such as “high flex” and “gender” specific designs have not demonstrated significant functional improvements in controlled series. Uncemented knees in many series have performed well for many surgeons from a fixation standpoint. Polymer wear must be addressed for long term durability

Fifteen-year survivorship studies demonstrate that total knee replacement have excellent survivorship, with reports of 85 to 97%. However, excellent survivorship does not equate to excellent patient reported outcomes. Noble et al. reported that 14% of their patients were dissatisfied with their outcome with more than half expressing problems with routine activities of daily living. There is also a difference in the patient's subjective assessment of outcome and the surgeon's objective assessment. Dickstein et al. reported that a third of total knee patients were dissatisfied, even though the surgeons felt that their results were excellent. Most of the patients who report lower outcome scores due so because their expectations are not being fulfilled by the total knee replacement surgery. Perhaps this dissatisfaction is a result of subtle soft tissue imbalance that we have difficulty in assessing intraoperatively and postoperatively. Soft tissue balancing techniques still rely on subjective feel for appropriate ligamentous tension by the surgeon. Surgical experience and case volume play a major role in each surgeon's relative skill in balancing the knee properly. New technology of “smart trials” with embedded microelectronics and accelerometers, used in the knee with the medial retinaculum closed, can provide dynamic, intra-operative feedback regarding knee quantitative compartment pressures and component tracking. After all bone cuts are made using the surgeon's preferred techniques, trial components with the sensored tibial trial are inserted and the knee is taken through a passive range of motion. After visualizing the resultant compartment pressures and tracking data on a graphical interface, the surgeon can decide whether to perform a soft tissue balance or a minor bone recuts. If soft tissue balancing is chosen, pressure data can indicate where to perform the release and allow the surgeon to assess the pressure changes as titrated soft tissue releases are performed. A multi-center study using smart trials has demonstrated dramatically better outcomes out to three years

Introduction & aims. Satisfaction following total knee replacement (TKR) surgery remains suboptimal at around 80%. Prediction of factors influencing satisfaction may help manage expectations and thus improve satisfaction. We investigated preoperative variables that estimate the probability of achieving a successful surgical outcome following TKR in several outcomes important to patients. Method. 9 pre-operative variables (easily obtained on initial consultation) of 591 unilateral TKRs were selected for univariant then multivariant analyses. These variables included Oxford Knee Score (OKS), age, sex, BMI, ASA score, pain score, mobility aids, SF12 PCS & SF12 MCS. Using the relative predictive strengths of these variables we modeled the probabilities a successful result would be achieved for 6 patient reported outcomes at 3 and 12 months following surgery. These were ‘Excellent/good OKS’, ‘Mild/no pain’, ‘Walking without/at first a limp’, ‘No/little interference with normal work’, ‘Kneeling with little/no difficulty’ and ‘Satisfaction with surgery’. Results. Pre-operative OKS was the most useful single predictor, having impact at three months and/or one year on all outcomes examined, except kneeling. SF12 MCS affected pain scores, pain with usual activity, and limp at three months and/or one year. At three months, BMI, age, gender, ASA and pain also influenced one or more of 6 post-operative outcomes studied. After inputting pre-operative OKS, adding other predictors did not significantly improve the statistical model. Conclusions. Our model provides objective probability estimates based on the outcomes of our previous TKRs, which we can use to give specific objective information to prospective TKR patients regarding their likely postoperative trajectory. We hope this will modulate patient expectations, assist preparation for their surgical experience and in turn increase satisfaction

Fifteen-year survivorship studies demonstrate that total knee replacements have excellent survivorship, with reports of 85 to 97%. However, excellent survivorship does not equate to excellent patient reported outcomes. Noble et al reported that 14% of their patients were dissatisfied with their outcome with more than half expressing problems with routine activities of daily living. There is also a difference in the patient's subjective assessment of outcome and the surgeon's objective assessment. Dickstein et al reported that a third of total knee patients were dissatisfied, even though the surgeons felt that their results were excellent. Most of the patients who report lower outcome scores due so because their expectations are not being fulfilled by the total knee replacement surgery. Perhaps this dissatisfaction is a result of subtle soft tissue imbalance that we have difficulty in assessing intraoperatively and postoperatively. Soft tissue balancing techniques still rely on subjective feel for appropriate ligamentous tension by the surgeon. Surgical experience and case volume play a major role in each surgeon's relative skill in balancing the knee properly. New technology of “smart trials” with embedded microelectronics and accelerometers, used in the knee with the medial retinaculum closed, can provide dynamic, intraoperative feedback regarding knee and component alignment along with quantitative compartment pressures and component tracking. After all bone cuts are made using the surgeon's preferred techniques, trial components with the sensored tibial trial are inserted and the knee is taken through a passive range of motion. After visualizing the resultant compartment pressures and tracking data on a graphical interface, the surgeon can decide whether to perform a soft tissue balance or minor bone recuts. If soft tissue balancing is performed, the surgeon can assess the pressure changes as titrated soft tissue releases are performed. A multicenter study using smart trials has demonstrated dramatically better outcomes at six months and one year