Learning curve for robotic assisted total knee arthroplasty: our experience with imageless hand-held Navio system.

The main purpose of this study was to determine the learning curve of Robotic assisted Total Knee Arthroplasty surgery through assessment of operative time and comparison with that of conventional jig based Total Knee Arthroplasty. The study included our first 75 Robotic assisted Total Knee Arthroplasty and 25 randomly selected conventional jig-based Total knee arthroplasty from June 2017 to December 2017. The 75 cases were divided into 3 groups of 25 consecutive cases. The mean of operative time for each phase and total time was compared between the 3 groups and with the mean of total time for conventional jig based group. In our experience, Robotic assisted Total Knee arthroplasty was associated with a learning curve of approximately 25 cases. The mean for Registration phase of Group A (1st set of 25 cases) was 6.12 min (SD 1.8 min), group B (2nd set of 25 cases) was 4.46 min (SD 0.79 min) and group C (3rd set of 25 cases) was 4.17 min (SD 0.59 min). The mean for Planning phase of group A was 5.08 min (SD 1.01 min), group B was 4.04 min (SD 0.37 min) and group C was 4.01 min (SD 0.35 min). The mean for Cutting Phase of group A was 28.22 min (SD 6.24 min), group B was 22.49 min (SD 0.79 min) and group C was 22.36 min (SD 0.88 min). The mean for total time of group A was 39.42 min (SD 8.02), group B was 31 min (SD 1.22 min), group C was 30.53 min (SD 1.14 min) and conventional group was 30.54 min (SD 1.14 min). On comparing the Registration phase (Group A vs B, p < 0.001; Group B vs C, p 0.14; Group A vs C, p < 0.001), Planning phase (Group A vs B, p < 0.001; Group B vs C, p 0.75; Group A vs C, p < 0.001), Cutting phase (Group A vs B, p < 0.001; Group B vs C, p 0.58; Group A vs C, p < 0.001) and Total time (Group A vs B, p < 0.001; Group B vs C, p 0.74; Group A vs C, p < 0.001; Group A vs Conventional, p < 0.001; Group B vs Conventional, p 0.17, Group C vs Conventional, p 0.99), the results showed that the inflection point for learning curve in our hands was 25 cases. The learning curve and increased operation theatre time are likely to be major barrier in widespread acceptance of robotic technology amongst arthroplasty surgeons. We, in our experience can say that the learning curve was approximately 25 cases. The results of this study will help the arthroplasty surgeons in accepting this technology and achieve better outcomes.

Robotic-assisted TKA leads to a better prosthesis alignment and a better joint line restoration as compared to conventional TKA: a prospective randomized controlled trial.

PURPOSE: Correct positioning and alignment of the prosthesis is a very important factor for durability of prosthesis and implant survival which is improved with the use of technology in total knee arthroplasty. However, the long-term functional outcomes and survivorship are unclear. For this study, it was hypothesized that mechanical axis alignment of lower limb, post-operative joint line restoration, femoral and tibial component alignment is more accurate with the new handheld semi-active robotic-assisted TKA. METHOD: From April-2019 to March-2020, 60 patients with unilateral knee osteoarthritis who underwent total knee arthroplasties were included in this prospective randomised controlled study. Computer generated randomization was used. Study included 48 female patients and 12 male patients. Pre-operative and post-operative radiographic measurements were done and compared between the two groups. RESULTS: There was a significant difference between two groups with respect to mechanical axis deviation, joint line deviation and coronal alignment of femoral and tibial prosthesis. Mechanical axis deviation > 3° was seen in eight cases (28.5%) in C-TKA group compared to one case (3.1%) in RA-TKA (p 0.019). Joint line deviation of 3.5 mm was noted in C-TKA group as compared to 0.9 mm in RA-TKA group (p < 0.001) which was statistically significant. However, whether this difference of 2.6 mm of joint line elevation between C-TKA and RA-TKA leads to any difference in clinical outcome in terms of knee kinematics and knee flexion needs to be investigated with further studies. Clinically restoring normal joint line is important for improved knee function after primary TKA. No significant difference was noted in femoral component rotation on post-operative computed tomography (CT) scan. CONCLUSION: The novel imageless, handheld semi-autonomous robotic system for TKA is highly accurate with respect to component positioning in coronal plane and mechanical alignment as compared to conventional TKA. Joint line is elevated in conventional TKA but is accurately restored using the robotic-assisted TKA which may lead to better patellofemoral kinematics. LEVEL OF EVIDENCE: I.

Assessment of accuracy of an imageless hand-held robotic-assisted system in component positioning in total knee replacement: a prospective study.

In recent years, robotic technology is becoming more pervasive in joint arthroplasty. The role of robotics in joint replacement surgery is to bring precision and accuracy in bone preparation, implant positioning and soft tissue balancing. However, there is yet to be a study conducted to determine the accuracy of bone preparation done by a new robotic system. The purpose of this study is to evaluate and report on the accuracy of bone cuts using imageless semiautonomous freehand robotic sculpting system, Navio (Smith & Nephew) based on the data provided by the robotic system. Between August 2018 and May 2019, a total of 62 patients were prospectively enrolled in this study. All surgeries were done by the senior author using a medial para-patellar approach and using a posterior stabilised implant (Anthem, Smith & Nephew Inc.). The study included 37 female patients and 25 male patients. The parameters assessed in this study were: (1) mechanical axis, (2) femoral coronal alignment, (3) femoral rotation, (4) femoral sagittal alignment, (5) tibial slope and (6) tibial coronal alignment using paired t test and root mean squared error (RMSE). The robotic system was accurate in achieving the bone cuts as planned in mechanical axis alignment (p = 0.89, RMSE = 0.56), femoral coronal alignment (p = 0.36, RMSE = 0.36), femoral sagittal alignment (p = 0.10, RMSE = 0.44), femoral rotation (p = 0.91, RMSE = 0.11), tibial coronal alignment (p = 0.81, RMSE = 0.24) and tibial slope (p = 0.30, RMSE = 0.37) with the maximum RMSE being 0.56. This study demonstrated that semi-autonomous hand-held robotic system, Navio (Smith & Nephew) for total knee arthroplasty produced accurate component positioning as per plan in all planes. The maximum RMSE was 0.56°.

Short-term follow-up of anterior and posterior both column fractures of acetabulum managed through both column plating.

OBJECTIVE: To evaluate the results of short-term follow-up of patients of both column acetabular fractures managed through anterior and posterior column plating. INTRODUCTION: Both column acetabular fractures are challenging articular injuries. Majority of them are treated operatively. The concept of "secondary congruence" was introduced by Letournel. Despite this, biomechanical data on secondary congruence indicate that nonoperative treatment leads to an increase in peak pressures in the supraacetabular region with the potential risk of developing posttraumatic degenerative osteoarthritis. Operative management is therefore justified. METHODOLOGY: A cohort of 10 patients having both column (anterior and posterior) acetabular fractures managed using bicolumnar plating between January 2016 and December 2017 were enrolled in the study and were analyzed during follow-up period. RESULTS: In total, 80% of the patients had excellent to good result. Average postoperative score was 85.7. Assessment was done using modified Harris Hip score.