Robotic Assistance in Unicompartmental Knee Arthroplasty Results in Superior Early Functional Recovery and Is More Likely to Meet Patient Expectations.

Robotic technology has reduced the errors of implant alignment in unicompartmental knee arthroplasty (UKA), but its impact on functional recovery after UKA is poorly defined. The purpose of this study was to compare early functional recovery, pain levels, and satisfaction in UKA performed with either robotic assistance or conventional methods. A retrospective analysis was performed on 89 matched consecutive patients who underwent outpatient UKA by a single physician using either conventional instruments (n = 39) or robotic methods (n = 50), with otherwise identical perioperative protocols. Outcomes studied included Lower Extremity Functional Score (LEFS), new Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR.), VR/SF-12, Visual Analog Scale (VAS) pain scores, and perioperative opioid consumption. Patients in the robotic cohort had superior early functional outcomes, with greater LEFS (conventional = 23; robotic = 31) at 1 week post-op (p=0.015) and KOOS-JR (conventional = 74; robotic = 81) at up to 6 months post-op (p=0.037); these two values remained statistically significant after mixed-model regression analysis (p=0.010; p=0.023), respectively. At 1 year post-op, expectations were more likely to be met in those who received robotic assistance (p=0.06). No differences were reported with respect to postoperative opioid usage (p=0.320), reoperations (p=1.00), and complications (p=0.628). Robotic-assisted UKA resulted in more rapid recovery and less early postoperative pain and were more likely to meet expectations than conventional UKA, although functional differences equilibrated by 1 year postoperatively. Further follow-up is necessary to determine if implant durability is impacted by robotics.

2018 John N. Insall Award: Recovery of Knee Flexion With Unsupervised Home Exercise Is Not Inferior to Outpatient Physical Therapy After TKA: A Randomized Trial.

BACKGROUND: Concerns about the cost and convenience of postsurgical physical therapy (PT) have sparked interest in unsupervised, home-based rehabilitation. However, the effectiveness of unsupervised home exercise after primary TKA has not been previously evaluated. QUESTIONS/PURPOSES: (1) Can unsupervised home exercise after surgery provide noninferior recovery of passive knee flexion compared with formal outpatient PT? (2) Does a web-based platform for home-based exercise provide an advantage compared with a printed PT manual? METHODS: We conducted a randomized, noninferiority trial involving 290 patients (20% of the 1464 eligible patients who could be contacted) who underwent primary TKA from March 2016 to April 2018. We included patients > 18 years old who were undergoing primary, unilateral TKA and provided written consent. We excluded patients with preoperative knee flexion < 90°, patients considering surgical intervention in a hip or the contralateral knee, patients discharged to an extended care facility, and revision or conversion TKA. We randomized patients to one of three groups: outpatient PT, unsupervised home exercise using a web-based platform (web PT), or unsupervised home exercise using a printed paper manual (paper PT). We also implemented a "delayed recovery intervention" within the home exercise program, in which patients were obliged to begin outpatient PT if knee flexion was < 70° at 2 weeks or < 90° at 4 weeks. The primary outcome was change in knee flexion from preoperative baseline after 4 to 6 weeks and 6 months. Secondary outcomes included Knee Injury and Osteoarthritis Outcome Score (KOOS), time back to activities of daily living, and time off narcotics. All analyses were intention to treat, and the noninferiority margin was 5% with maximum flexion as the outcome of interest for this parameter. RESULTS: Adjusted differences in change in passive flexion for web PT +3° (95% confidence interval [CI], -1.2° to 6.4°) and paper PT +5° (95% CI, 0.99°-8.6°) were not inferior to outpatient PT based on a predefined 5° margin. Change in knee flexion from baseline was 0° for outpatient PT, -2° for web PT, and -1° for paper PT after 4 to 6 weeks and 8°, 8°, and 12° for the three groups, respectively, after 6 months. Additionally, there was no difference in the change in KOOS from baseline at 4 to 6 weeks or 6 months postoperatively as well as time back to work, driving, and walking without an assistive device. CONCLUSIONS: Unsupervised home exercise is an effective rehabilitation strategy after primary TKA and was noninferior to formal outpatient PT in selected patients. It is worthwhile to reconsider the current practice of automatically designating patients for outpatient PT after primary TKA, because appropriately selected patients with adequate clinical support can achieve similar results at home. LEVEL OF EVIDENCE: Level I, therapeutic study.

The Role of Perioperative Surveillance in 90-Day Total Joint Arthroplasty Care.

BACKGROUND: With the recent implementation of a bundled payment model for total joint arthroplasty, healthcare providers are financially responsible for management of complications throughout the 90-day perioperative period. Our aim was to assess the effectiveness of a surveillance system that was implemented to enhance communication during this period. METHODS: A retrospective study was conducted using a prospectively collected database of patients who underwent primary total joint arthroplasty from January 2015 to April 2016. Surveillance was performed using electronic messages and telephone calls. The use of this system in response to several clinical scenarios was measured by the total number of messages and calls exchanged. RESULTS: Communication was greater among patients who experienced a complication (median 8), went to the emergency department (ED; median 9), and were readmitted to the hospital (median 8), relative to patients who had an uncomplicated course (median 5). Additionally, communication was greater among patients who presented to outside facilities for ED visits (median 11) and readmissions (median 9) relative to those who returned to the index hospital for ED visits (median 7) and readmissions (median 6). More distant patients had decreased follow-up attendance but did not have a compensatory increase in use of the surveillance system. CONCLUSION: Patients used the surveillance system to relay information about clinically significant events when such events arose. Additionally, patients who returned to outside facilities used the surveillance system to remain engaged with their original provider. However, more distant patients did not appear to use the surveillance system to compensate for decreased follow-up attendance.

The "Bundle Busters": Incidence and Costs of Postacute Complications Following Total Joint Arthroplasty.

BACKGROUND: Recently, a bundled payment model was implemented in the United States to improve quality and reduce costs. While hospitals may be rewarded for lowering costs, they may be financially exposed by high cost complications, the so-called bundle busters. We aimed at determining the incidence, etiology, and costs of postacute complications after total joint arthroplasty (TJA). METHODS: A retrospective study was conducted using a prospectively collected database of patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) from January 2015 to April 2016. Nurse navigators performed postoperative surveillance to identify patients with complications and unplanned clinical events in the 90-day postoperative period. This was combined with episode-of-care costs provided by third-party payers to derive the mean and per capita costs of postacute complications and clinical events. RESULTS: Among 3018 THA and 5389 TKA patients, 3.35% of THA and 2.62% of TKA patients sought emergency department or urgent care services, 2.62% of THA and 3.69% of TKA patients required hospital readmission, and 3.99% of TKA patients required manipulation. Joint-related complications were more common following THA, whereas medical complications were more frequent after TKA. The most costly complications after THA were periprosthetic fracture, dislocation, and myocardial infarction, compared to deep infection, myocardial infarction, and pulmonary embolism after TKA. CONCLUSION: Joint-related complications were among the most costly events after TJA, and given their higher incidence after THA, had a larger impact on per capita costs. Medical complications were more common after TKA and more costly. Despite these events, postacute complications made up less than 5% of the total 90-day costs of TJA.

Stepping Toward Objective Outcomes: A Prospective Analysis of Step Count After Total Joint Arthroplasty.

BACKGROUND: Functional recovery monitoring after total hip arthroplasty (THA) and total knee arthroplasty (TKA) is often limited to surgeon-based assessment and patient self-reporting rather than objective measures. However, traditional outcomes may not reliably gauge return of function. The goal of this study was to evaluate and compare an objective measure of postoperative recovery, daily step-count, with patient self-reported outcomes. METHODS: Prospectively, 589 patients used a mobile step-tracking application to record daily steps. Steps were recorded for 4 weeks before surgery and 12 weeks, thereafter. Patient-reported lower extremity functional scale (LEFS) scores were recorded at 1, 6, and 12 weeks, postoperatively. LEFS scores were correlated to weekly median daily steps using the Spearman rank correlation coefficient. RESULTS: Preoperative median daily steps were 2682 and 1988 for patients undergoing THA and TKA, respectively. Steps for weeks 1, 6, and 12 were 214, 3,170, and 3884 after THA and 153, 1772, and 2311 after TKA, respectively. Step-count demonstrated a weakly positive correlation with LEFS scores. For week 1, the correlation was 0.27 and 0.29 for THA and TKA patients, respectively. For week 6, the correlation was 0.18 and 0.29 for THA and TKA patients, respectively. CONCLUSION: Physical function improved over the first 12 weeks as measured by both steps and patient-reported assessments. Postoperative steps weakly correlated with LEFS scores, suggesting patient-reported outcomes may provide only part of the story. Incorporating objective measures may be a valuable addition to the surgeon's armamentarium for monitoring patient recovery.