Is Unicompartmental Arthroplasty an Acceptable Option for Spontaneous Osteonecrosis of the Knee?

Background  

The literature suggests survivorship of unicompartmental knee arthroplasties (UKAs) for spontaneous osteonecrosis of the knee ranges from 93% to 97% at 10 to 12 years. However, these data arise from small series (23 to 33 patients), jeopardizing meaningful conclusions.     

Is an “Outpatient Arthroplasty Risk Assessment Score” Needed for Predicting Safe Selection of Outpatient Arthroplasty Candidates?

BackgroundTotal joint arthroplasty is rapidly shifting to the outpatient space. One of the challenges of same-day discharge adoption has been determining which patients are suitable candidates. Risk assessment tools have been developed, including the Outpatient Arthroplasty Risk Assessment (OARA) score. The purpose of this study was to assess its predictive utility.MethodsA retrospective review was performed on all total joint arthroplasties performed at a single ambulatory surgery center in 2018, yielding a cohort of 1,105 patients (1,332 arthroplasties). The institution’s outpatient criteria required optimization of all medical conditions; if the patient had no failing organ, they were candidates for same-day discharge. OARA scores were calculated based on preoperative histories and physical examinations. Analyses were performed on the statistical utility of the OARA score in predicting successful same-day discharge. The mean age was 59 years (range, 27-82), the mean body mass index was 33.3 kg/m² (range, 16-66), and 51.5% were women. A total of 45% of patients had one or more major comorbidity.ResultsThere were 81.6% of patients who had an acceptable OARA score (<60). In addition, 97% of patients who had an “unacceptable” OARA score were successfully discharged the same day. There were 23 patients who required inpatient observation; of these, 7 (30.4%) had an OARA score ≥60.ConclusionThe OARA score was accurate in predicting patients who successfully had same-day discharge but poor at predicting who would not. This system is time consuming and may be too restrictive on which patients are candidates for outpatient arthroplasty. Surgeons may consider a more simplified criteria for outpatient arthroplasty.     

Is Bilateral Total Knee Arthroplasty Staged at a One-Week Interval Safe? A Matched Case Control Study

Controversy surrounds the safety of bilateral total knee arthroplasty (TKA) and whether staging the procedures one week apart represents a safer option. A consecutive series of 234 patients underwent either a simultaneous (103 patients) or staged bilateral TKA (131 patients) from 2007 to 2012 and were compared to a matched control group of unilateral TKA (131 patients). Staged patients had no difference in one-year complication rate when compared to simultaneous bilateral TKA and the matched unilateral TKA control group (15% vs. 19% vs. 15%, P = 0.512). There was also no difference in perioperative complications (10% vs. 14% vs. 7%, P = 0.231) or 90-day readmissions (8% vs. 4% vs. 4%, P = 0.295). In selected patients with bilateral knee OA, TKA staged at a one-week interval is a safe alternative.     

What Is the Critical Tibial Resection Depth During Unicompartmental Knee Arthroplasty? A Biomechanical Study of Fracture Risk

BackgroundFracture after medial unicompartmental knee arthroplasty (UKA) is a rare complication. Biomechanical studies evaluating association between depth of resection and maximum load to failure are lacking. The purpose of this study is to establish the relationship between depth of resection of the medial tibial plateau and mean maximum load to failure.MethodsMedial tibial resections were performed from 2 to 10 mm in 25 standardized fourth-generation Sawbones composite tibias (Sawbones, Vashon Island, Washington). A metal-backed tibial component with a 9-mm polyethylene bearing was used (Stryker PKR). Tibias were mounted on a biomechanical testing apparatus (MTESTQuattro) and axially loaded cyclically 10 times per cycle and incrementally increased until failure occurred.ResultsLoad to failure was recorded in 25 proximal tibia model samples after medial UKA using sequential resections from 2 to 10 mm. Analysis of variance testing identified significant differences in mean maximum load to failure between groups (P = .0003). Analysis of regression models revealed a statistically significant fit of a quadratic model (R² = 0.59, P = .0001). The inflection point of this quadratic curve was identified at 5.82 mm, indicating that the maximum load to failure across experimental models in this study began to decline beyond a resection depth of 5.82 mm.ConclusionIn this biomechanical model, medial tibial resections beyond 5.82 mm produced a significantly lower mean load to failure using a quadratic curve model. Resections from 2 to 6 mm showed no significant differences in mean load to failure. Identification of the tibial resection depth at which the mean load to failure significantly decreases is clinically relevant as this depth may increase the risk of periprosthetic fracture after a medial UKA.     

Is Outpatient Laparoscopic Cholecystectomy Safe and Cost-effective?: A Model to Study Transition of Care

Background: There is increasing pressure to perform traditional inpatient surgical procedures in an outpatient setting. The aim of the current trial was to determine the safety and cost savings of performing laparoscopic cholecystectomy in an outpatient setting using a "mock" outpatient setting.

Methods: Patients who were scheduled for laparoscopic cholecystectomy by four attending surgeons and for whom operating time was available in the outpatient center were studied. All patients received a standardized anesthetic, including ondansetron, and were discharged from the outpatient postanesthesia care unit if appropriate. At discharge, all patients were admitted to a clinical research center where they were observed in a "mock home" setting and monitored for complications that would have necessitated readmission. A decision analysis was created assuming all patients underwent outpatient surgery with either direct admission or discharge to home and readmission if complications developed.

Results: Of 99 patients who were enrolled in this study, 96 patients would have met the discharge criteria for home. No major complications were observed in these 96 patients. Eleven patients experienced postoperative nausea and vomiting, 3 of whom required an additional 24 h of hospital observation. In the decision model, the optimal strategy would be to perform the procedure on an outpatient basis and readmit patients only for complications, with an average baseline cost savings of $742/patient.     

Revision of Unicompartmental to Total Knee Arthroplasty: Does the Unicompartmental Implant (Metal-Backed vs All-Polyethylene) Impact the Total Knee Arthroplasty?

Background

The aim of this study is to investigate differences in implant requirement, outcomes, and re-revision when total knee arthroplasty (TKA) was performed following unicompartmental knee arthroplasties (UKAs) with metal-backed (MB) compared to all-polyethylene (AP) tibial components.

Is it Safe to Continue Clopidogrel in Elective Hip and Knee Arthroplasty?

BackgroundNo evidence-based guidelines exist for the perioperative use of clopidogrel in elective hip and knee arthroplasty patients. This study compares the preoperative, intraoperative, and postoperative outcomes of total hip and knee arthroplasty in patients maintained on clopidogrel and with patients whose clopidogrel was held before surgery.MethodsWe retrospectively identified 158 patients taking clopidogrel before undergoing elective total hip or knee arthroplasty. Patients were stratified for having clopidogrel held or continued, based on the interval between latest dose and date of surgery. The primary end points were receipt of transfusion and readmission within 90 days of surgery. Secondary end points were the incidence of complications such as bleeding, infection, re-operation, and major cardiac or neurologic events such as myocardial infarction or stroke during the 90-day postoperative period.ResultsThe two cohorts had similar demographics. Patients who continued clopidogrel were more likely to receive a blood transfusion postoperatively (9.1% vs 0%, P = .005), but there was no difference in wound drainage (P = .65), wound infection (P = .24), readmission (P = .74), major complications (P = .64), length of stay (P = .70), or mortality (P = .42). Patients who continued clopidogrel before surgery were more likely to have received general anesthesia (P < .001) per anesthesia protocol, however, three such patients did receive spinal anesthesia without any complications. With cementless implants, blood loss was not different between clopidogrel groups.ConclusionPatients undergoing elective total hip and knee arthroplasty may be safely maintained on clopidogrel without an increased risk of wound complications, infections, length of stay, readmission, reoperation, major medical complications, or mortality. Further prospective research is warranted to confirm the effects of continuing clopidogrel in patients undergoing elective hip and knee arthroplasty.     

Does Resident Involvement Impact Post-Operative Complications Following Primary Total Knee Arthroplasty? An Analysis of 24,529 Cases

Little is known about the impact of resident involvement on complication rates following total knee arthroplasty (TKA). The goal of our study was to determine the impact of resident involvement on complications following primary TKA. Using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database (2005–2012) we identified 24,529 patients who underwent primary TKA. Of these, 5960 (24.3%) had a resident involved in a primary TKA. Using a multivariate logistic regression which incorporated propensity score adjustment, no differences were seen in morbidity and mortality following those cases with resident involvement (OR: 1.15, P = 0.129). In the first large scale, comprehensive analysis of resident impact on short-term morbidity and mortality, no increase in complications was observed with resident involvement in primary TKA.     

Is Cementless Total Knee Arthroplasty Safe in Women Over 75 Y of Age?

BackgroundCementless total knee arthroplasty (TKA) is the subject of renewed interest. Previous concerns about survivorship have been addressed and there is an appeal in terms of biological fixation and surgical efficiency. However, even surgeon advocates have concerns about the risk of marked subsidence when using this technology in older patients at risk for osteoporosis.MethodsThis was a retrospective analysis of 1,000 consecutive fully cementless mobile bearing TKAs performed at a single institution on women over 75 years of age who had postoperative and 1-year x-rays. The primary outcome was the incidence of subsidence.ResultsThere were three asymptomatic cases with definite subsidence and change in alignment. In a fourth symptomatic case, the femoral component subsided into varus and the tibia into valgus, thus maintaining alignment which facilitated nonoperative treatment in a 92-year-old. Overall, at 1 year, there were two- liner revisions for infection without recurrence. Five patients had further surgery, of which three were washouts and two were for periprosthetic fractures sustained postoperatively within 1 year. Seven patients had further anesthesia, of which five were manipulations and two were nonrecurrent closed reductions for spinouts.ConclusionCementless TKA did not have a high risk of subsidence in this at-risk population. In the hands of experienced surgeons, these procedures can be used safely irrespective of bone quality.     

Are Patients With a History of Septic Arthritis Undergoing Total Knee Arthroplasty at Higher Risk for Revision Surgery? A Single-Center Study

BackgroundThe decision to perform a total knee arthroplasty (TKA) on a previously infected knee is made complicated by the higher risk for both a periprosthetic joint infection (PJI) and early failure. There is currently no standard in the treatment strategy for this group of patients. We here report the outcomes of performing a primary TKA on patients with a prior septic knee arthritis. The aim of our study is to analyze the survival rates of patients with a history of septic arthritis undergoing TKA.MethodsFrom 2010 to 2018, all patients treated in our institution with a minimum follow-up of 1 year, who have previous histories of knee joint infections and underwent a primary TKA were included in the study. All patients underwent the same surgical protocol and were given systemic and local antibiotic treatment.ResultsOf the 68 knees, there were 4 surgical revisions (5.9%). These included 2 septic revisions due to PJI (2.9%), 1 open arthrolysis for arthrofibrosis (1.5%), and 1 aseptic revision for implant loosening (1.5%). Sixty-four (64) knees (94%) had survived without any surgical interventions and the Kaplan-Meier analysis demonstrated an overall survivorship free from PJI of 97.1% at a mean of 5 years (range 1-9, standard deviation ±2.5 years).ConclusionTKA is a suitable option for patients with a prior septic arthritis of the knee, provided that proper surgical technique and the utilization of systemic and local antibiotics are employed.Level of EvidenceLevel III, therapeutic study.     

Is the Newest Fibrin Sealant an Effective Strategy to Reduce Blood Loss After Total Knee Arthroplasty? A Randomized Controlled Study

An RCT was conducted to ascertain whether, compared to control management, topical application of a novel fibrin sealant (Evicel, J&J) in patients undergoing primary TKA reduces peri-operative blood loss. Sixty-two patients were randomized to receive topical application of Evicel (N = 31) or not (N = 31). The mean total blood loss was 1.9 L(± 0.7) in the control group and 1.8 L(± 0.5) in the treatment group (P = 0.4). The transfusion rate was 32.3% in the control group and 25.8% in the treatment group (P = 0.5). The transfusion rate decreased linearly with increasing preoperative Hb levels in the treatment group (P = 0.005). The results of this study suggest that topical application of this novel fibrin sealant doesn't reduce perioperative blood loss and the need for allogeneic blood transfusion.     

Is a Titanium Implant for Total Knee Arthroplasty Better? A Randomized Controlled Study

BackgroundLighter weight and lower modulus are potential advantages of titanium (Ti) implants over cobalt chrome (CoCr) implants in total knee arthroplasty (TKA). This study was conducted to determine whether Ti implants in TKA resulted in better clinical outcomes and radiologic results.MethodsOne hundred and eight patients (216 knees) with knee arthritis warranting bilateral primary TKA were randomly allocated to undergo Ti rotating-platform TKA in one knee and CoCr rotating-platform TKA in the contralateral knee. The mean follow-up period was 5.3 years (range, 1-7 years). The weight of Ti implants was one-third lighter than that of CoCr implants (133.9 g vs 390.1 g, P < .01). Clinical outcomes were evaluated using clinical scores, patient preferences (lightness, comfort, naturalness, and satisfaction), gait analysis (kinetic and kinematic data), range of motion, and degree of pain. Radiologic results were evaluated based on the radiolucent line (RLL), degree of medial tibial bone loss, and loosening as seen on X-ray.ResultsNo significant differences were observed in clinical scores or patient preference. Regarding implant weight, approximately 70% of patients did not perceive the Ti implant as lighter. No significant differences were observed in gait analysis, range of motion, or degree of pain. The RLL was seen in 9% of the Ti implant group and 19% of the CoCr implant group.ConclusionThe lighter Ti implant did not show any clinical benefit over CoCr implants. The lightness of the Ti implant is not sufficient to matter or be noticeable. However, the Ti implant showed lower rate of RLL than the CoCr implant.Level of Evidencelevel I, randomized controlled trial.     

Is the Medial Wall of the Intercondylar Notch Useful for Tibial Rotational Reference in Unicompartmental Knee Arthroplasty?

Background  

It is difficult to implant components in the correct rotational position in the narrow operating field in a unicompartmental knee arthroplasty. Although no rotational reference has been confirmed for unicompartmental knee arthroplasty, the AP axis of the tibia may serve as a reference for unicompartmental knee arthroplasty and TKA. However, it is difficult to identify the AP axis during unicompartmental knee arthroplasty, especially with the tibia first-cut technique.     

Does Risk Mitigation Reduce 90-Day Complications in Patients Undergoing Total Knee Arthroplasty?: A Cohort Study

BackgroundWith ever-increasing demand for total knee arthroplasty (TKA), most healthcare systems around the world are concerned about its socioeconomic burden. Most centers have universally adopted well-defined clinical care pathways to minimize adverse outcomes, maximize volume, and limit costs. However, there are no prospective comparative trials reporting benefits of these risk mitigation (RM) strategies.MethodsThis is a prospective cohort study comparing post-TKA 90-day complications between patients undergoing RM before surgery and those following a standard protocol (SP). In the RM group, we used a 20-point checklist to screen for modifiable risk factors and evaluate the need for optimizing non-modifiable comorbidities. Only when optimization goals were achieved, patients were offered TKA.ResultsTKA was performed in 811 patients in the SP group and in 829 in the RM group, 40% of which were simultaneous bilateral TKA. In both groups, hypertension was the most prevalent comorbidity (48%), followed by diabetes (20%). A total of 43 (5.3%) procedure-related complications were seen over the 90-day postoperative period in the SP group, which was significantly greater than 26 (3.1%) seen in the RM group (p = 0.039). The commonest complication was pulmonary thromboembolic, 6 in each group. Blood transfusion rate was higher in the SP group (6%) than in the RM group (< 1%).ConclusionsScreening and RM can reduce 90-day complications in patients undergoing TKA.     

Is There a Preferred Articulating Spacer Technique for Infected Knee Arthroplasty?: A Preliminary Study

Background  

Periprosthetic infection in TKA is a devastating and challenging problem for both patients and surgeons. Two-stage exchange arthroplasty with an interval antibiotic spacer reportedly has the highest infection control rate. Studies comparing static spacers with articulating spacers have reported varying ROM after reimplant, which could be due to differences in articulating spacer technique.     

Is High Flexion Following Total Knee Arthroplasty Safe?: Evaluation of Knee Joint Loads in the Patients During Maximal Flexion

The purpose of this study was to indicate the mechanical loads and the flexion angle at the knee during rise from maximal flexion following total knee arthroplasty (TKA). Twenty three knees were evaluated using skin marker-based motion analysis system during four different activities of daily living. The average maximum flexion was 90 degrees (34 degrees less than passive flexion) and all subjects required support for their weight to rise from maximal flexion. The external moments and the external forces at the knee during the maximal flexion were smaller than those during the stair descending activity. The results indicate that capable flexion angle for the patients following TKA is approximately 90 degrees which has smaller mechanical loads at the knee than the stair descending activity.     

Does Implant Selection Impact Postoperative Complications Following Hip Arthroplasty for Failed Intertrochanteric Fractures? A Retrospective Comparative Study

The purpose of this study is to compare postoperative complications among different acetabular and femoral components of hip arthroplasty for failed intertrochanteric fractures. A total of 79 patients were included and followed‐up for an average of 75.6 months (range, 24–244). Fifty‐five patients underwent total hip arthroplasty, and 24 had bipolar hemiarthroplasty. Cementless metaphyseal locking, cementless diaphyseal locking, and cemented standard stems were used in 41, 29, and 9 patients, respectively. Dislocation and wear rate were not different between the total hip arthroplasty and bipolar hemiarthroplasty groups. Stem subsidence or loosening was more frequently found in the cementless, metaphyseal locking stem groups. In conclusion, cemented standard stem and cementless diaphyseal locking stem might be better implant choices. With regard to dislocation rate, our results were insufficient to conclude a better implant choice of total hip arthroplasty or bipolar hemiarthroplasty than the other.     

Is There a Disadvantage to Early Physical Therapy After Multiligament Surgery for Knee Dislocation? A Pilot Randomized Clinical Trial

BackgroundMultiligament knee injuries, though rare, can be profoundly disabling. Surgeons disagree about when to initiate rehabilitation after surgical reconstruction due to the conflicting priorities of postoperative stability and motion.Questions/purposes(1) Does early or late initiation of physical therapy after multiligament knee surgery result in fewer postoperative manipulations? (2) Does early versus late physical therapy compromise stability postoperatively? (3) Does early initiation of physical therapy result in improved patient-reported outcomes, as measured by the Multi-ligament Quality of Life (ML-QOL) score?MethodsBetween 2011 and 2016, 36 adults undergoing multiligament repair or reconstruction were prospectively enrolled in a randomized controlled trial and randomized 1:1 to either early rehabilitation or late rehabilitation after surgery. Eligibility included those with an injury to the posterior cruciate ligament (PCL) and at least one other ligament, as well as the ability to participate in early rehabilitation. Patients who were obtunded or unable to adhere to the protocols for other reasons were excluded. Early rehabilitation consisted of initiating a standardized physical therapy protocol on postoperative day 1 involving removal of the extension splint for quadriceps activation and ROM exercises. Late rehabilitation consisted of full-time immobilization in an extension splint for 3 weeks. Following this 3-week period, both groups engaged in the same standardized physical therapy protocol. All surgical reconstructions were performed at a single center by one of two fellowship-trained sports orthopaedic surgeons, and all involved allograft Achilles tendon PCL reconstruction. When possible, hamstring autograft was used for ACL and medial collateral ligament reconstructions, whereas lateral collateral ligament and posterolateral reconstruction was performed primarily with allograft. The primary outcome was the number of patients undergoing manipulation during the first 6 months. Additional outcomes added after trial registration were patient-reported quality of life scores (ML-QOL) at 1 year and an objective assessment of laxity through a physical examination and stress radiographs at 1 year. One patient from each group was not assessed for laxity or ROM at 1 year, and one patient from each group did not complete the ML-QOL questionnaires. No patient crossover was observed.ResultsWith the numbers available, there was no difference in the use of knee manipulation during the first 6 months between the rehabilitation groups: 1 of 18 patients in the early group and 4 of 18 patients in the late group (p = 0.34). Similarly, there were no differences in knee ROM, stability, or patient-reported quality of life (ML-QOL) between the groups at 1 year.ConclusionWith the numbers available in this study, we were unable to demonstrate a difference between early and late knee rehabilitation with regard to knee stiffness, laxity, or patient-reported quality of life outcomes. The results of this small, randomized pilot study suggest a potential role for early rehabilitation after multiligament reconstruction for knee dislocation, which should be further explored in larger multi-institutional studies.Level of EvidenceLevel II, therapeutic study.