Precision vs. tradition: evaluating alignment accuracy and functional outcomes in robotic vs. conventional total knee arthroplasty

Ravikumar Mukartihal; Kamal Jain; Ameya Katariya; Tomin P. Zacharias; Kartik P. N.; Sharan Patil

doi:10.18203/issn.2455-4510.IntJResOrthop20253425

Authors

Ravikumar Mukartihal Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India
Kamal Jain Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India https://orcid.org/0000-0002-6121-9319
Ameya Katariya Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India
Tomin P. Zacharias Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India
Kartik P. N. Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India
Sharan Patil Department of Orthopaedics, Sparsh Hospital, Bengaluru, Karnataka, India

DOI:

https://doi.org/10.18203/issn.2455-4510.IntJResOrthop20253425

Keywords:

Total knee arthroplasty, Total knee, Arthroplasty, Robotic surgery, Mechanical alignment, Functional outcomes, Osteoarthritis

Abstract

Background: Total knee arthroplasty (TKA) is the treatment of choice in severe osteoarthritis (OA) knee. Robot-assisted TKA (RA-TKA) promises superior precision and personalized bone resection and alignment, whereas conventional TKA (C-TKA) relies on manual alignment techniques. This randomized controlled trial compares alignment accuracy and short-term functional outcomes between the two modalities.

Methods: 100 patients with bilateral knee OA were randomized to RA-TKA (n=50) or C-TKA (n=50). Postoperative mechanical alignment (hip-knee-ankle (HKA) angle) and functional outcomes (new knee society score (NKSS) and forgotten joint score (FJS)) were assessed at 6 months.

Results: RA-TKA achieved significantly better alignment, with 82% of patients within±3° of the target HKA angle compared to 64% in C-TKA (p<0.01). However, functional outcomes were comparable: KSS (RA-TKA: 205.42±6.52 vs. C-TKA: 205.4±7.94, p=0.989) and FJS (RA-TKA: 88.6±4.07 vs. C-TKA: 88.92±4.16, p=0.662).

Conclusions: RA-TKA offers improved alignment accuracy over C-TKA but does not confer superior short-term functional outcomes. Despite achieving more precise mechanical alignment, no significant differences in key functional scores are observed within six months postoperatively. The potential long-term benefits of this improved alignment, such as increased implant longevity or reduced wear, remain unconfirmed and warrant further investigation in studies with extended follow-up.

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