Robotic-arm assisted versus manual total knee arthroplasty: Functional gait analysis from a randomised controlled trial.

The primary aim of this study was to assess whether measures of functional gait assessment were improved with robotic total knee arthroplasty (rTKA) when compared to manual TKA (mTKA). Gait analysis was performed as part of a randomised controlled trial. Walking and relaxed standing assessments were performed using an instrumented mat system. Spatiotemporal variables included gait cycle parameters, anteroposterior and lateral sway, and plantar pressure ratios. Measurements were recorded at pre-operative baseline and 12 months post-operatively. 100 patients were randomised, 50 to each group. Complete gait cycle data were available for 26 rTKA and 23 mTKA patients. Cadence and walking velocity showed overall improvements following surgery, with no difference between the two groups. In the operated limb, overall step and stride times decreased, while step and stride lengths increased. Subgroup analysis showed reduced propulsion time with rTKA, and decreased foot flat and mid stance times with mTKA. Lateral sway was decreased in the rTKA group. Plantar pressure ratios showed an overall increase in hindfoot loading on the operated limb, with no difference between the two groups. No other significant differences were identified between rTKA and mTKA at 12 months, and limitations may include statistical error. A small sample of the study cohort was followed up; analysis may represent the results of satisfied patients with well-functioning TKA. Further study could incorporate proprioceptive and 3D gait analysis techniques to analyse knee kinetics and kinematics with robotic surgery. Pressure mapping could further subdivide the plantar surfaces to explore any nuances in differential loading.

Identifying subgroups of patients that may benefit from robotic arm-assisted total knee arthroplasty: Secondary analysis of data from a randomised controlled trial.

BACKGROUND: The aims were to assess whether a specific subgroup(s) of patients had a clinically significant benefit in their knee specific outcome or health-related quality of life (HRQoL) when undergoing robotic total knee arthroplasty (rTKA) when compared to manually performed TKA (mTKA). METHODS: One hundred patients were randomised to either rTKA or mTKA, 50 to each group, of which 46 and 41 were available for functional review at 6-months, respectively. Subgroup analysis was undertaken for sex, age (<67-years versus ≥ 67-years), preoperative WOMAC score (<40 versus ≥ 40) and EQ-5D utility (<0.604 versus ≥ 0.604). RESULTS: Male patients undergoing rTKA had a clinically and statistically significant greater improvement in WOMAC pain (mean difference (MD) 16.3, p = 0.011) at 2-months, function (MD 12.6, p = 0.032) and total score (MD 12.7, p = 0.030), and OKS (MD 6.0, p = 0.030) at 6-months. Patients < 67-years old undergoing rTKA had a clinically and statistically significant greater improvement in WOMAC pain (MD 10.3, p = 0.039) at 2-months, and function (MD 12.9, p = 0.040) and total (MD 13.1, p = 0.038) scores at 6-months. Patients with a preoperative WOMAC total score of < 40 points undergoing rTKA had a clinically and statistically significant greater improvement in WOMAC pain (MD 14.6, p = 0.044) at 6-months. Patients with a preoperative EQ-5D utility of <0.604 undergoing rTKA had a clinically and statistically significant greater improvement in WOMAC pain (MD 15.5, p = 0.011) at 2-months. CONCLUSION: Patients of male sex, younger age, worse preoperative knee specific function and HRQoL had a clinically significantly better early functional outcome with rTKA when compared to mTKA.

Patients undergoing robotic arm-assisted total knee arthroplasty have a greater improvement in knee-specific pain but not in function.

Aims: The aim was to assess whether robotic-assisted total knee arthroplasty (rTKA) had greater knee-specific outcomes, improved fulfilment of expectations, health-related quality of life (HRQoL), and patient satisfaction when compared with manual TKA (mTKA). Methods: A randomized controlled trial was undertaken (May 2019 to December 2021), and patients were allocated to either mTKA or rTKA. A total of 100 patients were randomized, 50 to each group, of whom 43 rTKA and 38 mTKA patients were available for review at 12 months following surgery. There were no statistically significant preoperative differences between the groups. The minimal clinically important difference in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score was defined as 7.5 points. Results: There were no clinically or statistically significant differences between the knee-specific measures (WOMAC, Oxford Knee Score (OKS), Forgotten Joint Score (FJS)) or HRQoL measures (EuroQol five-dimension questionnaire (EQ-5D) and EuroQol visual analogue scale (EQ-VAS)) at 12 months between the groups. However, the rTKA group had significantly (p = 0.029) greater improvements in the WOMAC pain component (mean difference 9.7, 95% confidence interval (CI) 1.0 to 18.4) over the postoperative period (two, six, and 12 months), which was clinically meaningful. This was not observed for function (p = 0.248) or total (p = 0.147) WOMAC scores. The rTKA group was significantly (p = 0.039) more likely to have expectation of 'Relief of daytime pain in the joint' when compared with the mTKA group. There were no other significant differences in expectations met between the groups. There was no significant difference in patient satisfaction with their knee (p = 0.464), return to work (p = 0.464), activities (p = 0.293), or pain (p = 0.701). Conclusion: Patients undergoing rTKA had a clinically meaningful greater improvement in their knee pain over the first 12 months, and were more likely to have fulfilment of their expectation of daytime pain relief compared with patients undergoing mTKA. However, rTKA was not associated with a clinically significant greater knee-specific function or HRQoL, according to current definitions.

Robotic Arm-assisted versus Manual (ROAM) total knee arthroplasty: a randomized controlled trial.

Aims: The primary aim was to assess whether robotic total knee arthroplasty (rTKA) had a greater early knee-specific outcome when compared to manual TKA (mTKA). Secondary aims were to assess whether rTKA was associated with improved expectation fulfilment, health-related quality of life (HRQoL), and patient satisfaction when compared to mTKA. Methods: A randomized controlled trial was undertaken, and patients were randomized to either mTKA or rTKA. The primary objective was functional improvement at six months. Overall, 100 patients were randomized, 50 to each group, of whom 46 rTKA and 41 mTKA patients were available for review at six months following surgery. There were no differences between the two groups. Results: There was no difference between rTKA and mTKA groups at six months according to the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) functional score (mean difference (MD) 3.8 (95% confidence interval (CI) -5.6 to 13.1); p = 0.425). There was a greater improvement in the WOMAC pain score at two months (MD 9.5 (95% CI 0.6 to 18.3); p = 0.037) in the rTKA group, although by six months no significant difference was observed (MD 6.7 (95% CI -3.6 to 17.1); p = 0.198). The rTKA group were more likely to achieve a minimal important change in their WOMAC pain score when compared to the mTKA group at two months (n = 36 (78.3%) vs n = 24 (58.5%); p = 0.047) and at six months (n = 40 (87.0%) vs n = 29 (68.3%); p = 0.036). There was no difference in satisfaction between the rTKA group (97.8%; n = 45/46) and the mTKA group (87.8%; n = 36/41) at six months (p = 0.096). There were no differences in EuroQol five-dimension questionnaire (EQ-5D) utility gain (p ≥ 0.389) or fulfilment of patient expectation (p ≥ 0.054) between the groups. Conclusion: There were no statistically significant or clinically meaningful differences in the change in WOMAC function between mTKA and rTKA at six months. rTKA was associated with a higher likelihood of achieving a clinically important change in knee pain at two and six months, but no differences in knee-specific function, patient satisfaction, health-related quality of life, or expectation fulfilment were observed.

Robotic- and orthosensor-assisted versus manual (ROAM) total knee replacement: a study protocol for a randomised controlled trial.

BACKGROUND: Robotic-arm-assisted knee arthroplasty allows for more accurate component positioning and alignment and is associated with better patient-reported outcomes compared to manually performed jig-based knee arthroplasty. However, what is not known is whether the addition of an intra-articular sensor (VerasenseTM) to aid intraoperative balancing of the total knee replacement (TKR) offers improved functional outcomes for the patient. The purpose of this research is to compare the outcomes of patients undergoing a conventional manual knee replacement to those undergoing TKR using robotic-assisted surgery and the VerasenseTM to optimise alignment and balance the knee joint, respectively, and assess the associated cost economics of such technology. METHODS AND ANALYSIS: This randomised controlled trial will include 90 patients with end-stage osteoarthritis of the knee undergoing primary TKR. Patients meeting the inclusion/exclusion criteria that consent to be in the study will be randomised at a ratio of 1:1 to either manual TKR (standard of care) or robotic-arm-assisted TKR with VerasenseTM to aid balancing of the knee. The primary objective will be functional improvement at 6 months following surgery between the two groups. The secondary objectives are to compare changes in knee-specific function, joint awareness, patient expectation and fulfilment, satisfaction, pain, stiffness and functional ability, health-related quality of life, cost-effectiveness, and gait patterns between the two groups. Ethical approval was obtained by the Tyne & Wear South Research Ethics Committee, UK. The study is sponsored by the Newcastle Hospitals NHS Foundation Trust. DISCUSSION: This study will assess whether the improved accuracy of component positioning using the robotic-arm-assisted surgery and the VerasenseTM to aid balancing of the TKR offers improved outcome relative to standard manual jig-based systems that are currently the standard of care. This will be assessed primarily according to knee-specific function, but several other measures will also be assessed including whether these are cost-effective interventions. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number ISRCTN47889316 https://doi.org/10.1186/ISRCTN47889316 . Registered on 25 November 2019 DATE AND VERSION FOR PROTOCOL: ROAM Protocol V1.0 (13-12-2018).