Dr. Russell Cohen on Mako’s CT-based planning approach    

Message from Russell Cohen, MD

Tucson Orthopaedic Institute - Phoenix, AZ

Having performed robotic-arm assisted surgery with Mako for 3 years, I’ve become accustomed to knowing more about my patients prior to my first cut. Looking back on my manual approach, I’m amazed by how much more information and concrete data I have at my disposal to make planning and surgical decisions based on the unique anatomy and functional needs of my patients.

At the upcoming AAHKS meeting in Dallas, TX, in November, I’ll be chairing a symposium on Mako and its CT-based approach to personalized surgery. I’m excited to discuss Mako with my fellow panelists and dive deeper into new scientific data and research by my peers.

Top 5 things I like about Mako’s CT-based planning

5. Knowing more. The information Mako’s 3D CT scan provides is real data—not just an algorithmic approximation of my patient’s bone. This helps me to know more about their individual, unique anatomy including osteophytes, cysts and obscure bony defects. This is especially useful when performing difficult cases, but also essential for the routine cases we perform every day. It’s knowledge you simply don’t have with a 2D imaging model.

4. Intra-operative adjustments. Knowing my patient’s real anatomy in 3D enables me to adjust my plan intra-operatively based on my patient’s soft tissue for joint balancing and line restoration. The ability to balance the soft tissue before committing to bone resections has helped create a more customized experience for my patients.

3. Accuracy and precision. The CT scan enables the haptically guided robotic-arm assisted cutting tool, which allows me to precisely execute my plan1,2,3. My experience echoes several published clinical studies which have shown that Mako has demonstrated higher accuracy and precision to plan for implant placement in all three Mako applications compared to manual techniques1,4,5.

2. Cutting less. My experience with Mako’s AccuStopTM haptic technology is similar to what has been reported in the literature. With Mako Total Knee I’m noticing more pristine bone resections and less soft tissue damage when compared to manual cutting blocks6, less removal of healthy acetabular bone with Mako Total Hip’s single stage reaming7, and bone preservation with Mako Partial Knee and the Restoris MCK implant system8. With Mako, I cut what I plan and cut less than I ever did using manual instruments6,7,8.

1. Encouraging results. Across all three applications, Mako Robotic-Arm Assisted Surgery has shown better outcomes compared to manual surgery2,9,10,11. These published outcomes correlate to what I have seen in my own patients. This includes promising early functional outcomes for Mako Total Knee9,10, the THA highest Forgotten Joint Score (FJS) for Mako Total Hip12, and one of the lowest partial knee revision rates in the Australian registry for Mako Partial Knee13


  1. Anthony I, Bell SW, Blyth M, Jones B et al. Improved accuracy of component positioning with robotic-assisted unicompartmental knee arthroplasty. J Bone Joint Surg AM. 2016;98-A(8): 627-35.
  2. Illgen R, Bukowski B, Abiloa R, Amderson P, Chughtai M, Klopas A, Mont M. Robotic-assisted total hip arthroplasty: Outcomes at minimum two year follow up. Surgical Technology International. 2017 July 25; 30:365-372.
  3. Mahoney O, KIinsey T, Mont M, Hozack W, Orozco F, Chen A. Can computer generated 3D bone models improve the accuracy of total knee component placement compared to manual instrumentation: a prospective multi-center evaluation? International Society for Technology in Arthroplasty 32nd Annual Congress. Toronto, Canada. October 2-5, 2019.
  4. Hampp EL, Chughtai M, School LY, Sodhi N, Bhowmik-Stoker M, Jacofsky DJ, Mont MA. Robotic-Arm Assisted Total Knee Arthroplasty demonstrated greater accuracy and precision to plan compared with Manual Techniques. J Knee Surg. 2018 May 1. [Epub ahead of print].
  5. Domb B, Redmond J, Louis S, Alden K, Daley R, LaReau J, et al. Accuracy of component positioning in 1980 total hip arthroplasties: a comparative analysis by surgical technique and mode of guidance. The Journal of Arthroplasty. 30(2015)2208-2218.
  6. Kayani, B., Konan, S., Pietrziek, J., Haddad, F. S. Iatrogenic Bone and Soft Tissue Trauma in Robotic-Arm Assisted Total Knee Arthroplasty Compared with Conventional Jig-Based Total Knee Arthroplasty: A Prospective Cohort Study and Validation of a New Classification System. The Journal of Arthroplasty 2018.
  7. Suarez-Ahedo, C; Gui C; Martin, T; Chandrasekaran, S; Domb, B. Robotic-arm assisted total hip arthroplasty results in smaller acetabular cup size in relation to the femoral head size: A Matched-Pari Controlled Study. Hip Int. 2017; 27 (2): 147-152.
  8. Hampp E, Chang TC, Pearle A. Robotic partial knee arthroplasty demonstrated greater bone preservation compared to robotic total knee arthroplasty. Annual Orthopaedic Research Society. Austin, TX. 2-5 Feb 2019
  9. Kayani B, Konan S, Tahmassebi J, Pietrzak JRT, Haddad FS. Robotic-arm assisted total knee arthroplasty is associated with improved early functional recovery and reduced time to hospital discharge compared with conventional jig-based total knee arthroplasty: a prospective cohort study. The Bone and Joint Journal. 2018;100-B:930-7.
  10. Marchand RC, Sodhi N, Khlopas A, Sultan AA, Harwin SF, Malkani AL, Mont MM. Patient satisfaction outcomes after robotic-arm assisted total knee arthroplasty: a short-term evaluation. J Knee Surg. 2017;30(9):849-853.
  11. Kleebald LJ, Borus T, Coon T, Dounchis J, Nguyen J, Pearle A. Midterm survivorship and patient satisfaction of robotic-arm assisted medial unicompartmental knee arthroplasty: a multicenter study. The Journal of Arthroplasty. 2018:1-8.
  12. Peret I, Walsh JP, Close MR, Mu BH, Yuen LC, Domb BG. Robot-assisted total hip arthroplasty: Clinical outcomes and complication rate. Int J Med Robotics Comput Assist Surg. 2018;14:e1912.
  13. Australian Orthopedic Association national Joint Replacement Registry (AOANJRR). Annual Report 2018.