Robotic-Assisted Total Knee Arthroplasty is Safe in the Ambulatory Surgery Center Setting.

BACKGROUND: Robotic-assisted total knee arthroplasty (RA-TKA) has become more popular in the United States. With the significant trend towards performing TKA in outpatient and ambulatory surgery center (ASC) settings, this study was implemented to determine the safety and efficacy of RA-TKA in an ASC. METHOD: A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded. RESULTS: In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups. CONCLUSIONS: Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes. METHOD: A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded. RESULTS: In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups. CONCLUSIONS: Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes.

Changes in Neuraxial Anesthesia Protocols and Improved Efficiency of Same-Day Discharge Total Knee Arthroplasty in an Ambulatory Surgery Center: A Retrospective Cohort Study.

INTRODUCTION: This study evaluated the effect of bupivacaine versus mepivacaine spinal anesthesia and preoperative adductor canal block (ACB) on recovery, length of stay, pain, and complications of same-day discharge total knee arthroplasty (TKA) at a free-standing ambulatory surgery center. METHODS: We performed a retrospective review of patients who underwent TKA between March 2018 and September 2019. The patients were grouped based on the neuraxial anesthetic regimen: bupivacaine with ACB, bupivacaine without ACB, and mepivacaine without ACB. Preoperative ACBs were discontinued in December 2018, and use of mepivacaine spinal anesthesia was initiated in March 2019. Length of stay in the postanesthesia care unit (PACU), time to controlled void and ambulation, postoperative pain, morphine milligram equivalents (MME), and transient neurologic symptoms were compared. RESULTS: Ninety consecutive patients who underwent TKA were identified. Fifty patients received bupivacaine with ACB, 20 received bupivacaine without ACB, and 20 received mepivacaine without ACB. Mepivacaine spinal anesthesia led to a 93-minute shorter PACU stay (P < 0.001), 115-minute quicker time to void (P < 0.001), 60-minute earlier ambulation (P = 0.024), and 109-minute shorter total facility time (P = 0.003) but increased total MME (P = 0.049) despite nonsignificant difference in pain at discharge (P = 0.908) compared with bupivacaine. Patients receiving bupivacaine with and without ACB had a nonsignificant difference in pain scores at discharge, time to ambulation, and time to discharge (P ≥ 0.1). No transient neurologic symptoms or overnight stays were observed. DISCUSSION: Mepivacaine spinal anesthesia for TKA safely facilitated more rapid same-day discharge through decreased times to controlled void and ambulation but with a slight increase in MME requirements. Discontinuing preoperative ACBs did not negatively affect PACU outcomes.

Hip Arthroplasty Femoral Stem Designs and Their Association With Early Postoperative Periprosthetic Femoral Fractures.

BACKGROUND: Periprosthetic femoral fractures (PFFs) in total hip arthroplasty (THA), especially those in contact with the diaphyseal stem, carry high morbidity. This study evaluated how stem design influences the risk of early Vancouver B PFF or other PFF requiring operative intervention after THA. METHODS: A multicenter, retrospective study of 3,433 primary cementless THAs performed from 2014 to 2021 included 2,302 single-taper (micro M/L [n = 1,169]; M/L [n = 1,133]) and 1,131 double-taper (fit-and-fill [n = 420]; compaction-collared [n = 711]) stems. Mean follow-up was 2.2 years (range, 0.3 to 6.5 years). Primary outcomes were Vancouver B and surgically treated postoperative PFFs among differing femoral stems. Secondary outcomes included rates of intraoperative and postoperative Vancouver A and C PFFs. RESULTS: Forty five postoperative PFFs (1.3%) occurred within 8.8 weeks (median), 25 of which were Vancouver B (0.7%) and 20 total PFFs that required operative intervention (0.6%). Compaction-collared stems had a decreased risk of Vancouver B (hazard ratio 0.18, 95% confidence interval: 0.03-0.97 P = .044) and any surgically treated PFF (hazard ratio 0.10, 95% confidence interval: 0.01-0.95; P = .037). Intraoperative PFFs were most common with fit-and-fill stems (3.6%, P < .001) and Vancouver A with compaction-collared stems (1.8%, P < .001). The cohort with PFF had a higher Charlson comorbidity index (P = .004), more women (P = .001), more Dorr A or C femora (P = .013), and more posterior or lateral surgical approaches compared to those without PFF (P ≤ .001). CONCLUSION: After controlling for confounding variables, compaction-collared stems had a significantly lower risk of postoperative Vancouver B and PFF requiring operative treatment than single-taper and double-taper stems.

Mepivacaine vs Bupivacaine Spinal Anesthesia in Total Hip Arthroplasty at an Ambulatory Surgery Center.

BACKGROUND: Mepivacaine spinal anesthetic may facilitate more rapid postoperative recovery in joint arthroplasty than bupivacaine. This study compared recovery, pain, and complications between the 2 anesthetics in anterior-approach total hip arthroplasty (THA) at a free-standing ambulatory surgery center (ASC). METHODS: This retrospective cohort study of 282 consecutive patients with mean age 55.7 ± 8.8 years and body mass index 30.6 ± 5.3 who underwent THA at an ASC from November 2018 to July 2020 compares mepivacaine (n = 141) vs bupivacaine (n = 141) spinal anesthesia, a transition made in March 2019. The main outcomes were length of stay in the postoperative unit (post acute care unit) prior to same-day discharge (SDD), time to controlled void, and ambulation. Secondarily, postoperative pain scores (0-10) with morphine equivalents were required and any postoperative complications were compared. RESULTS: Mepivacaine decreased mean post acute care unit stay (4.0 vs 5.7 hours, P < .001), time to void (3.1 vs 4.9 hours, P < .001), and ambulation (3.2 vs 4.5 hours, P < .001). No patients needed urinary catheterization or overnight stay. Two patients in the bupivacaine group had transient neurologic symptoms, consisting of foot drop and spinal headache, compared to none with mepivacaine (P = .498). Mepivacaine patients had increased postoperative pain at 2 hours (1.7 vs 0.9, P < .001), at discharge (1.1 vs 0.5, P = .004), and morphine equivalent doses received (7.8 vs 3.7 mg, P < .001). CONCLUSION: Mepivacaine spinal anesthesia for anterior-approach THA safely facilitated more rapid SDD from the ASC through decreased times to controlled void and ambulation with only minor increase in pain when compared to bupivacaine. LEVEL OF EVIDENCE: Level III - Retrospective comparative cohort study.

Risk Factors for Prolonged Time to Discharge in Total Hip Patients Performed in an Ambulatory Surgery Center due to Complaints of the Inability to Void.

BACKGROUND: Postoperative urinary retention (POUR) is among the reasons for delay in discharge after outpatient total hip arthroplasty (THA), occurring in 2%-46% of patients. We hypothesized that the frequency of POUR following outpatient THA in the ambulatory surgery center (ASC) is low compared to previously reported rates and that management can be effective in the perioperative period when it is encountered. METHODS: Three hundred seventy-seven THA patients (409 hips) who had arthroplasties in the ASC over a 5-year period were identified. Preoperatively, appropriate demographic information and medical comorbidities were collected from patient health history questionnaires completed during clinic visits. Intraoperatively, albumin volume administered and estimated blood loss were recorded. Postoperatively, post-anesthesia care unit medications, patients who reported an inability to urinate, and those who required urinary catheterization were recorded. RESULTS: POUR occurred in only 2 patients but complaints of the inability to void occurred in 38 others for an incidence of 9.8%. Factors associated with POUR and the inability to urinate included older age, time spent in the ASC, and intraoperatively albumin volume administered. No significant differences were found in body mass index, preoperative hematocrit, estimated blood loss, surgical time, or operating time. CONCLUSION: POUR was infrequent but the reported inability to urinate was not (9.8%) and can be safely managed when it does occur and we found that increased age and albumin volume over 500 mL may increase the risk for a prolonged length of stay due to the inability to urinate.

Blood Management in Outpatient Total Hip Arthroplasty.

Based on a series of 407 outpatient total hip arthroplasties performed by a single surgeon, a standardized protocol for blood loss management in outpatient arthroplasty was developed consisting of a presurgical hematocrit of greater than 36%, administration of tranexamic acid, prophylactic introduction of albumin, hypotensive epidural anesthesia, monopolar electrocautery, and bipolar sealer. This protocol uses techniques that alone are not novel but together create a standardized and reproducible pathway that when implemented can increase the safety of outpatient hip arthroplasty.

Anterior Supine Intermuscular Total Hip Arthroplasty at an Ambulatory Surgery Center Versus Hospitalization: Cost and Adverse Events.

This study compares anterior supine intermuscular total hip arthroplasty performed at an ambulatory surgery center with the same procedure performed in a hospital setting in regard to complications and costs. The ambulatory surgery center had significantly shorter postoperative stays and superior visual analog pain scores at 3 months. No differences were noted in operative time, blood loss, or complications. Costs were significantly different between groups, with significant cost savings noted in the ambulatory surgery center group.

Total Knee Arthroplasty in Freestanding Ambulatory Surgery Centers: 5-Year Retrospective Chart Review of 90-Day Postsurgical Outcomes and Health Care Resource Utilization.

INTRODUCTION: Migration of total knee arthroplasty (TKA) procedures from the inpatient setting to outpatient venues, especially freestanding ambulatory surgery centers (ASCs), requires the use of reliable patient selection algorithms and standardized perioperative pathways to facilitate favorable outcomes for patients. METHODS: This retrospective chart review included consecutive TKA procedures performed over a 5-year period between January 2014 and January 2019 at 2 freestanding ASCs. The patient selection algorithm was developed on the basis of patient comorbidities to minimize the potential for adverse events. All procedures were performed by one of eight orthopedic surgeons who were identified a priori as adhering to similar multimodal pain management regimens, including the use of spinal anesthesia, general or monitored-care anesthesia, adductor canal blocks, pericapsular injection of liposomal bupivacaine, nonsteroidal anti-inflammatory drugs, gabapentin, tramadol, acetaminophen, and oxycodone on an as-needed basis. Outcomes, including surgical complications, healthcare resource utilization (HCRU), and patient satisfaction, were measured before discharge and at a 90-day follow-up visit. RESULTS: Four hundred thirty-nine TKA procedures in 386 patients were identified for inclusion. Of these patients, 115 (29.8%) were performed in patients with the American Society of Anesthesiologists physical status IIIa. Mean (standard deviation) length of stay at the ASC was 500 (107) minutes, including 136 (47) minutes of surgery and 201 (78) minutes to ambulation. The overall rates of surgical complications and 90-day hospital admissions were low (1.4% and 0.7%, respectively), as was the need for additional HCRU, including additional surgical procedures related to index surgery, emergency department visits, and unplanned clinic visits or calls. At the 90-day follow-up visit, 96% of patients reported being pleased with their outcomes. DISCUSSION: With careful patient selection, standardized perioperative pathways, and multimodal analgesia protocols, TKA procedures can be performed in the ASC setting with low complication rates, minimal postdischarge HCRU, and high rates of patient satisfaction. LEVEL OF EVIDENCE: III.

Defining Outpatient Hip and Knee Arthroplasties: A Systematic Review.

INTRODUCTION: The term "outpatient" has a variety of meanings regarding the location of arthroplasty and the duration of stay postoperatively. The purpose of this systematic review was to evaluate the literature and more accurately define the term "outpatient." METHODS: A PubMed search (2014 to 2019) using the terms "outpatient AND arthroplasty" identified 76 studies; 35 studies that met the inclusion criteria were assessed to determine the definition of "outpatient." The level of evidence, type of arthroplasty, location of surgery (hospital or ambulatory surgery center [ASC]), approach used for hip arthroplasty, number of patients, number of surgeons, and length of time the patients were kept at the location after surgery were evaluated. RESULTS: Arthroplasties analyzed were total hip (11), total knee (seven), unicompartmental knee (five), and hip and knee (12). Only 16.8% of surgeries defined as outpatient hip or knee arthroplasty were done in a freestanding ASC, and 44.2% of patients defined as outpatients were kept overnight for the 23-hour observation. DISCUSSION: We propose "DASH" (Discharge from ASC to Home) as a new term to define arthroplasties done in an outpatient setting with the patient discharged home the same day.

Outpatient Hip Safety in an Ambulatory Surgery Center Is Independent of Approach.

BACKGROUND: There are few data comparing the direct anterior approach (DAA) and posterior approach (PA) for total hip arthroplasty (THA) in the outpatient setting. The purpose of this study is to compare 90-day complications between the 2 approaches. We hypothesized that they would be equally safe and effective. METHODS: Retrospective review identified 432 THAs (346 DAA, 86 PA) performed at a single ambulatory surgery center (ASC). Outcomes compared included demographics, comorbidities, preoperative and discharge pain scores (visual analog scale [VAS]), overall time spent in the ASC, overnight stay, emergency room visits, admission, reoperation, and complications within a 90-day period. RESULTS: There were no differences in mean preoperative VAS (DAA 4.7, PA 4.5), mean discharge VAS (DAA 0.8, PA 0.7), overall time spent in the ASC (DAA 9.0 hours, PA 9.3 hours), total number of overnight stays (DAA 0.9%, PA 1.2%), emergency room visits (DAA 1.7%, PA 1.2%), admissions (DAA 1.4%, PA 1.2%), reoperations (DAA 1.4%, PA 1.2%), or complications (DAA 3.5%, PA 2.3%). CONCLUSION: There were no differences in the safety outcomes, and overall there were few complications in the 90-day period, regardless of the surgeon's preferred approach. This study indicates both DAA and PA are equally safe for THA in the outpatient setting, and the choice of surgical approach should be based on patient and surgeon preference.

Low Rates of Adverse Events Following Ambulatory Outpatient Total Hip Arthroplasty at a Free-Standing Surgery Center.

BACKGROUND: We proposed to determine the complication and hospital admission rates for patients with total hip arthroplasty (THA) done by a single surgeon in a stand-alone ambulatory surgical center with same-day discharge. Given the recent emphasis on bundled payments for a 90-day episode of care, this same time frame after surgery was chosen to determine patient outcomes. METHODS: The records of patients with THAs done through a direct anterior approach by a single surgeon at 2 separate ambulatory surgery centers were reviewed. To analyze the learning curve for outpatient THA, the procedures were arbitrarily divided into 2 groups depending on when they were done: early in our experience or later. Complications were recorded, as were hospital admissions and surgical interventions, length of surgery and blood loss, and time spent at the outpatient facility. RESULTS: Over a 3-year period, 145 outpatient THAs were done in 125 patients; 73 were considered to be initial procedures, and 72 were considered to be later procedures. Only one of the 145 procedures (0.7%) required transfer from the outpatient facility to the hospital for a blood transfusion. No other direct admissions to the hospital or transfers to the emergency department from the surgery center were necessary. Surgical interventions were required after 3 (2%) of the 145 arthroplasties in the global period (90 days). CONCLUSION: This study demonstrated that same-day discharge to home following THA can be safely done without increased complications, readmissions, reoperations, or emergency room visits.

Distal Femoral Replacement for Acute Distal Femoral Fractures in Elderly Patients.

OBJECTIVES: To evaluate outcomes and complications using cemented modular distal femoral replacement in elderly patients with distal femoral fractures. DESIGN: Retrospective chart review, case series. SETTING: A Level 1 and Level 2 trauma center, both tertiary referral hospitals. PATIENTS/PARTICIPANTS: Eighteen patients older than 60 years (average age 77 years) who had cemented distal femoral replacement for distal femoral fractures (comminuted, intraarticular, osteoporotic, arthritic) between 2005 and 2013. Patients with previous knee surgery were excluded. INTERVENTION: Cemented modular distal femoral replacement. MAIN OUTCOME MEASURES: Implant status, complications, Knee Society Score, Musculoskeletal Tumor Society score, and Western Ontario and McMaster Osteoarthritis Index. RESULTS: All patients were extremely or very satisfied with their outcomes. For patients with functional outcome data, Knee Society Score averaged 85.7 with a functional score of 35, Musculoskeletal Tumor Society score averaged 19.2, and Western Ontario and McMaster Osteoarthritis Index score averaged 23.1 at an average follow-up of 2.3 years. Range of motion was 1-99 degrees. Implant-related complications occurred in 2 patients (11%); one required revision to total femoral replacement because of periprosthetic fracture and the other had a deep infection that required exchange of the components. No patient had aseptic loosening or patellar maltracking. There were no perioperative deaths or late amputations. CONCLUSIONS: Cemented modular distal femoral replacement is a viable treatment option in elderly patients that permits immediate full weight-bearing, with most patients returning to preoperative functional status. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Proprioception and Knee Arthroplasty: A Literature Review.

Proprioceptive mechanoreceptors provide neural feedback for position in space and are critical for three-dimensional interaction. Proprioception is decreased with osteoarthritis of the knees, which leads to increased risk of falling. As the prevalence of osteoarthritis increases so does the need for total knee arthroplasty (TKA), and knowing the effect of TKA on proprioception is essential. This article reviews the literature regarding proprioception and its relationship to balance, aging, osteoarthritis, and the effect of TKA on proprioception. Knee arthroplasty involving retention of the cruciate ligaments is also reviewed, as well the evidence of proprioception in the posterior cruciate ligament after TKA.

Osteosarcoma tumor thrombus: a case report with a review of the literature.

Tumor thrombus arising from osteosarcoma is rare. We report the case of a 20-year-old man with proximal humerus osteosarcoma, accompanied by an extensive intravascular tumor thrombus extending into the heart. Our review of the literature found 14 previous reports on osteosarcoma with tumor thrombus. The combination of positron emission tomography and computed tomography is very useful in differentiating tumor thrombus from vascular thrombus, thereby avoiding unnecessary anticoagulation therapy. This same imaging combination can also be used to evaluate the response to treatment. Surgical resection of the tumor thrombus is highly recommended. The effect of tumor thrombus on survival is still unknown.

Distal femoral osteoarticular allografts: long-term survival, but frequent complications.

BACKGROUND: Complications are frequent with osteoarticular allografts, and their long-term survivorship in the distal femur is unclear. Thus, the benefits of osteoarticular allografting remain controversial. QUESTIONS/PURPOSES: We therefore determined the frequency of complications in osteoarticular allografts of the distal femur relative to their potential long-term survival. METHODS: We retrospectively reviewed 26 patients who had osteoarticular allograft reconstruction of the distal femur after resection of a malignant or aggressive benign tumor of bone. The minimum followup was 15 months (average, 156 months; range, 15-283 months) for all patients and 98 months (average, 191 months; range, 98-283 months) for the surviving patients. RESULTS: At last followup, 16 of the 26 original allografts were still in place. The overall 5-year and 10-year allograft survival rates were 69% and 63%, respectively. The 5-year and 10-year survival rates of the joint surface were 79% and 65%, respectively. Eleven patients retained their original osteoarticular allograft without a resurfacing procedure, and nine had been converted to allograft-prosthetic composites. Five patients were converted to megaprostheses and one had an amputation for local recurrence. At last followup, 25 of 26 patients retained a functional limb. CONCLUSIONS: Osteoarticular allograft reconstructions of the distal femur can provide long term survival and restore function but the risk of complications and their physical and monetary costs for patients are not trivial. Lacking the benefit of improved soft tissue attachments inherent in other anatomic sites, we believe this option is most appropriate for restoring bone stock in young patients with expectations of long-term survival.

Reconstruction of noncontained proximal tibial defects with divergent screws and cement.

Postoperative fracture is a well described complication following curettage and cementation of aggressive benign bone tumors. We asked whether: (1) the addition of diverging screws that engage the opposite cortex increase the strength and rigidity of the construct in the proximal tibia compared with (a) cement alone and (b) would cement with intramedullary Steinmann pins; and (2) the modes of failure be different for those constructs. The average load to failure for tibias reconstructed with cement augmented with diverging screws (6321 +/- 681 N) was higher than for tibias reconstructed with cement alone (2343 +/- 222 N). The average load to failure for tibias reconstructed with cement augmented with diverging screws (6885 +/- 445 N) was higher than for tibias reconstructed with cement and intramedullary Steinmann pins (5218 +/- 941 N). Furthermore, constructs with cement augmented with diverging screws were less likely to fail by an intraarticular fracture than other types of constructs. Our data support the use of diverging screws that engage the opposite cortex to augment the strength of the construct when using acrylic cement to fill noncontained defects after curettage of the proximal tibia. This more stable, stronger construct might allow earlier mobilization and rehabilitation after curettage, with a decreased risk of fracture.

Reconstruction of noncontained distal femoral defects with polymethylmethacrylate and crossed-screw augmentation: a biomechanical study.

BACKGROUND: Curettage and cementation with polymethylmethacrylate are frequently used in the treatment of aggressive benign bone lesions such as giant-cell tumors, but strength and stiffness of the reconstructed bone have been concerns. This biomechanical study was undertaken to determine whether augmenting the cement with crossed screws would result in a stronger reconstruction. METHODS: Large noncontained defects were created in the medial femoral condyles of twenty matched pairs of human cadavera. Four groups were organized to compare three types of reconstruction: (1) polymethylmethacrylate alone, (2) polymethylmethacrylate and intramedullary Steinmann pins, and (3) polymethylmethacrylate with crossed screws engaging the opposite cortex. The specimens were subjected to 2000 compressive cycles and were subsequently monotonically loaded to failure under a controlled displacement rate. Failure load and stiffness were determined for each femur that survived the cycling process. RESULTS: Femora reconstructed with crossed screws and cement failed at higher loads and had greater stiffness than those reconstructed with cement alone (p = 0.025 and p = 0.0007) or cement augmented with intramedullary Steinmann pins (p = 0.019). Failure of femora reconstructed with cement and crossed screws occurred through an extra-articular transverse fracture, while failure in those with cement alone and cement with Steinmann pins occurred through an intra-articular (intercondylar) fracture. CONCLUSIONS: In this in vitro cadaver study, augmentation of polymethylmethacrylate cement with crossed screws resulted in a stronger reconstruction of distal femoral tumor defects than that obtained with cement alone or with cement and intramedullary Steinmann pins.