Robotic assisted total knee arthroplasties show better anatomical and mechanical alignment compared to conventional methods but similar clinical and functional outcomes

by | Sep 12, 2024 | Blog

Alrajeb R, Zarti M, Shuia Z, Alzobi O, Ahmed G, Elmhiregh A. Robotic-assisted versus conventional total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials. Eur J Orthop Surg Traumatol. 2024;34(3):1333-1343. doi:10.1007/s00590-023-03798-2

Abstracted by:

Lindsy Moore, PT, DPT, OCS, COMT Soldotna, Alaska – Fellowship Candidate, IAOM-US Fellowship Program & Jean-Michel Brismée, PT, ScD, Fellowship Director, IAOM-US Fellowship program.

 Research: To provide high level, evidence-based comparison between robotic total knee replacements and conventional methods, focusing on radiological and functional outcomes. The study aimed to determine if robotic assisted surgeries offered superior results in terms of prosthesis positioning, alignment restoration, and overall clinical and functional outcomes compared to traditional knee replacement techniques.

Methods: This was a meta-analysis of the current role of robotic technology in total knee arthroplasty (TKA) which includes randomized control trials. A systematic literature search was performed up to July 2022 in PubMed/Medline, CINAHL, Cochrane, EMBASE, and Google Scholar. These articles were found in peer reviewed journals. The study investigated patients undergoing TKA with cemented prosthesis. The study included a total of 1942 knees from seven randomized control trials (RCTs). Out of these, 974 knees were implanted using robotic arms, while 968 knees utilized conventional jig-based knee systems. The interventions in the study compared robotic-assisted total knee arthroplasty (RTKA) with conventional total knee arthroplasty (CTKA). The study used the ROBODOC and NAVIO systems for RTKA. The comparison group is patients undergoing conventional jig-based TKA.

Outcome Measures: Knee society scores: Clinical and functional scores to assess pain and function. WOMAC Score: Evaluates pain, stiffness, and physical function. Hospital of special surgery score (HSS): Measures overall knee function. Knee range of motion: Assesses the flexibility and movement of the knee joint. Radiological alignment: and includes parameters like tibiofemoral angle, mechanical axis, and femoral flexion angle.

Results: Robotic assisted total knee replacements showed significantly better anatomical and mechanical alignment compared to conventional methods. While robotic knees had a better range of motion, the difference was not statistically significant. Both robotic and conventional methods had similar clinical and functional outcomes. The rate of complications was statistically similar between the two groups.

Comments:

Robotic assisted total knee arthroplasty offers better post operative anatomical and mechanical alignment compared to conventional methods.1 Clinical and functional outcomes, as well as complication rates, are similar between robotic TKA and conventional TKA.1 Despite the improved alignment with robotics, the patient satisfaction and functional outcomes do not show significant differences.1 More randomized control trials with the latest robotic systems are needed to confirm any superior functional and clinical outcomes from robotic TKA.1

Research from other studies using robotic TKA suggests that superior alignment in TKA offers several benefits. Better alignment can enhance knee function and range of motion, leading to more natural movement patterns.2 Proper alignment reduces wear and tear on the implant, potentially extending its lifespan.2 Accurate alignment can minimize postoperative pain and discomfort by ensuring even distribution of forces across the knee.2 Superior alignment contributes to overall knee stability, reducing the risk of complications such as implant loosening.2 These benefits highlight the importance of precision in knee replacement surgeries.

Balanced flexion extension gaps and proper medial lateral ligamentous tensioning are essential for optimizing knee kinematics, stability, and long-term implant survivorship.3 Robotic TKA uses optical motion capture technology to assess intraoperative alignment, component positioning, range of motion, flexion-extension gaps, and medial lateral laxity.3 The real time interoperative data can then be used to fine tune bone resection and guide implant positioning to achieve the desired knee kinematics and limit the need for additional soft tissue releases.3

Robotic TKA is associated with reduced post operative pain, decreased analgesia requirements, shorter time to straight leg raise, increased flexion at discharge, and reduced need for inpatient physiotherapy compared to conventional jig based TKA.4–6 The robotic TKA shows improved early functional outcomes and time to hospital discharge however long-term outcomes are still like conventional methods.4

Limitations of robotic TKA include substantial installation and maintenance cost, additional radiation exposure with image-based platforms, and increased operative times during the learning phase.7 On average one study found that during the learning phase the surgery was extended compared to conventional based methods.7 Thereafter, the surgery times were similar.

These insights can help physical therapists understand the potential benefits and limitations of robotic TKA in their practice. In the community I work in we have conventional and robotic knee arthroplasties. Our hospital has the ROSA robot and clinically as a PT I have noticed improved short-term outcomes. Specifically, less swelling, reduced pain, and improved range of motion with early return functional mobility.

 

References:

  1. Alrajeb R, Zarti M, Shuia Z, Alzobi O, Ahmed G, Elmhiregh A. Robotic-assisted versus conventional total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials. Eur J Orthop Surg Traumatol. 2024;34(3):1333-1343. doi:10.1007/s00590-023-03798-2
  2. Agarwal N, To K, McDonnell S, Khan W. Clinical and Radiological Outcomes in Robotic-Assisted Total Knee Arthroplasty: A Systematic Review and Meta-Analysis. J Arthroplasty. 2020;35(11):3393-3409.e2. doi:10.1016/j.arth.2020.03.005
  3. Kayani B, Konan S, Ayuob A, Onochie E, Al-Jabri T, Haddad FS. Robotic technology in total knee arthroplasty: a systematic review. EFORT Open Rev. 2019;4(10):611-617. doi:10.1302/2058-5241.4.190022
  4. B K, S K, J T, Fe R, Fs H. An assessment of early functional rehabilitation and hospital discharge in conventional versus robotic-arm assisted unicompartmental knee arthroplasty: a prospective cohort study. Bone Jt J. 2019;101-B(1). doi:10.1302/0301-620X.101B1.BJJ-2018-0564.R2
  5. W S, S M, R K, Pf H. Technique and first clinical results of robot-assisted total knee replacement. The Knee. 2002;9(3). doi:10.1016/s0968-0160(02)00015-7
  6. Fontalis A, Kayani B, Asokan A, et al. Inflammatory Response in Robotic-Arm-Assisted Versus Conventional Jig-Based TKA and the Correlation with Early Functional Outcomes. J Bone Jt Surg. 2022;104(21):1905-1914. doi:10.2106/JBJS.22.00167
  7. N S, A K, Ns P, et al. The Learning Curve Associated with Robotic Total Knee Arthroplasty. J Knee Surg. 2018;31(1). doi:10.1055/s-0037-1608809