Cemented total knee arthroplasty provides greater knee range of motion at 2 years than cementless technique.

INTRODUCTION: Optimal fixation method between cemented, cementless, and hybrid techniques for total knee arthroplasty (TKA) is still debated. The purpose of this study is to evaluate the clinical outcomes of patients undergoing cemented versus cementless TKA. METHODS: We reviewed 168 patients who underwent a primary TKA at a single academic institution between January 2015 and June 2017. Patients were categorized into cemented (n = 80) or cementless (n = 88) groups. Only patients with greater than or equal to 2-year follow-up were included in the study. Multivariate regressions were performed to analyze the relationship between the surgical fixation technique and the clinical outcomes. RESULTS: There were no differences in demographics or baseline operative characteristics between the two groups. The cemented group had fewer manipulations under anesthesia (MUA) (4 vs. 15, p = 0.01), longer intraoperative tourniquet times (101.30 vs. 93.55 min, p = 0.02), and increased knee range of motion (ROM) at final follow-up (111.48 vs. 103.75°, p = 0.02) compared to the cementless group. DISCUSSION AND CONCLUSION: Both cemented and cementless component fixation are viable options for (TKA). This study found that patients who underwent a cemented TKA required fewer MUA's and had greater final ROM compared to patients undergoing cementless TKA. Additional research is required regarding cementless and cemented fixation. We believe that the choice of which fixation technique to use ultimately comes down to patient characteristics and surgeon preference.

Do Intra-articular Corticosteroid Injections Prior to Total Knee Arthroplasty Increase Postoperative Complication Rates: A Retrospective Review.

There is conflicting literature suggesting that intra-articular corticosteroid injections before total knee arthroplasty (TKA) may lead to an increase in the rate of postoperative complications, specifically periprosthetic joint infection (PJI). Thus, this retrospective review of all TKAs performed at a large, urban hospital will add valuable evidence to help guide future patient care. After exclusion criteria, we retrospectively reviewed 417 patients who received a TKA from a group of fellowship-trained orthopaedic surgeons between 2009 and 2016 at a single academic medical center. Minimum follow-up time was 1 year. Patients were separated into two groups: those who received a preoperative intra-articular corticosteroid injection and those who did not receive an injection. Subgroups were created based on the timing of their most recent preoperative injection: 0 to 3 months, 3 to 6 months, 6 to 12 months, 12+ months, and an unknown time period. Postoperative outcomes for PJI, revision TKA, and manipulation under anesthesia (MUA) were analyzed via a Chi-square test. No statistically significant postoperative differences were observed between groups: PJI (p = 0.904), revision TKA (p = 0.206), and MUA (p = 0.163). The temporal subgroups also failed to demonstrate a statistically significant result: PJI (p = 0.348), revision TKA (p = 0.701), and MUA (p = 0.512). This study revealed no absolute or temporal association between preoperative, intra-articular corticosteroid injections, and complications after TKA. Because these injections are a commonly used treatment modality prior to TKA, further studies should be conducted on a nationwide basis to draw more concrete conclusions.

Fourth-Generation Ceramic Head Fracture in Dual Mobility Total Hip Arthroplasty: A Case Report.

Introduction: Rare cases of Biolox® delta ceramic head fractures in ceramic-on-polyethylene bearings have been reported in the literature. Virtually none of these catastrophic injuries have been documented in dual mobility constructs. Case Report: We report a case of fourth-generation delta ceramic head fracture 4.5 years after implantation in a dual mobility total hip replacement constructs as a result of a ground-level fall. The patient underwent revision arthroplasty with another delta ceramic dual mobility construct and was able to return to work in custodial services 2 weeks after the revision procedure. Conclusion: In summary, we presented an extremely uncommon case of a fractured fourth generation, Biolox® delta ceramic head in a dual mobility total hip arthroplasty (THA), as a result of a ground-level fall. The patient underwent successful revision surgery to another dual mobility delta ceramic THA. Despite substantial advances in ceramic materials, catastrophic failure of 4th generation ceramic head components can still occur even in dual mobility constructs and require revision arthroplasty surgery.

Aerobic capacity and fatigability are associated with activity levels in women with hip osteoarthritis.

Physical activity is important for physical function and pain relief in people with lower extremity osteoarthritis (OA). Unfortunately, people with OA are not as active as their peers without OA. The objective of this study was to determine whether aerobic capacity and fatigability are associated with physical activity in women with hip OA. We conducted a cross-sectional analysis of 36 women with hip OA. We assessed aerobic fitness as predicted VO2 max from a 6-min walk test. We assessed fatigability using a treadmill test. Finally, we assessed self-reported physical activity using the UCLA activity scale and quantified steps per day and activity intensity using accelerometers. We used Pearson correlations to determine associations. We used regression analysis to determine whether fatigability mediated the association between aerobic fitness and physical activity. On average, subjects were moderately active via the UCLA score (5.2 ± 1.3 out of 10). Aerobic fitness (R = 0.582, p < .001) and fatigability (R = 0.516, p =.003) were significantly correlated with UCLA scores. However, aerobic fitness was the best predictor of UCLA scores, as well as sedentary time, and time spent in light activity. Fatigability was not a mediator between aerobic fitness and UCLA scores. Aerobic fitness and fatigability may be modifiable barriers to physical activity in people with OA. Future interventional studies should examine whether improving aerobic fitness improves physical activity or fatigability.

Arthroscopic Lysis of Adhesions With Manipulation Under Anesthesia Versus Manipulation Alone in the Treatment of Arthrofibrosis After TKA: A Matched Cohort Study.

Arthrofibrosis following total knee arthroplasty (TKA) is a debilitating complication. Treatment options include physical therapy, manipulation under anesthesia (MUA), and arthroscopic lysis of adhesions (ALOA) with or without MUA. The authors studied 70 patients with arthrofibrosis after TKA treated with MUA or ALOA plus MUA. In this matched cohort study, 35 patients were treated with MUA and 35 patients were treated with ALOA plus MUA. Total knee arthroplasty followed by MUA was performed by 2 surgeons and TKA followed by MUA plus ALOA was performed by 1 surgeon at 1 institution. Electronic records were used to collect information and match cohorts based on age, sex, body mass index, diabetes mellitus, perioperative range of motion (ROM), and timing of the procedure for arthrofibrosis. The combination of MUA and ALOA yielded changes in ROM: a 72.7% increase 4 to 12 weeks after index TKA (P=.032), a 50.0% increase 12+ weeks after TKA (P=.032), and a 99.8% increase in patients with a pre-manipulation ROM of 0° to 60° (P=.001). Manipulation under anesthesia yielded a 49.2% increase 4 to 12 weeks after TKA (P=.161), a 27.0% increase 12+ weeks after TKA (P=.161), and a 68.8% increase in patients with pre-manipulation ROM of 0° to 60° (P=.084). Patients treated with ALOA plus MUA had greater increases in ROM (P=.026) and final knee flexion (P=.028) compared with those treated with MUA alone. Arthrofibrosis following TKA is a complication that often requires additional procedures. Traditionally, ALOA is added 3+ months from index TKA, when abundant scar formation has occurred. This study found a benefit to ALOA plus MUA compared with MUA alone, with the largest benefit in patients whose pre-manipulation ROM was 0° to 60°. [Orthopedics. 2019; 42(3):163-167.].

Static and dynamic abductor function are both associated with physical function 1 to 5 years after total hip arthroplasty.

BACKGROUND: A subset of total hip arthroplasty patients experience functional impairments past the first postoperative year. Poor hip abductor function is common before and in the early postoperative period. It is not known if abductor impairment is associated with long-term functional impairment. This study evaluated the relationships between static and dynamic abductor function and performance-based and self-reported function >1 year post-total hip arthroplasty. METHODS: Eighteen adults 1-5 years post-total hip arthroplasty participated. Static and dynamic abductor function were assessed through dynamometry and gait analysis, respectively. Subjects completed four physical performance tests and two self-report instruments. FINDINGS: Higher peak isometric abductor strength was associated with better performance-based function (P ≤ 0.001-0.030) and with self-reported function (P ≤ 0.001-0.012). Higher peak external adduction moment was associated with better results on 3 of 4 performance tests (P = 0.007-0.026). Together, static and dynamic abductor function predicted 35-77% of the variation in physical function. Abductor strength best predicted walking test results and self-reported function, while dynamic abductor function best predicted tests involving sit-to-stand INTERPRETATION: Static and dynamic abductor function were associated with physical function 1-5 years after total hip arthroplasty. These results support further investigation of interventions targeting abductor function for persons experiencing persistent impairments.

Patient dissatisfaction following total knee arthroplasty: external validation of a new prediction model.

Tools designed to predict patient satisfaction following total knee arthroplasty (TKA) have the potential to guide patient selection. Our study aimed to validate a model that predicts patient satisfaction following TKA. Phone surveys were administered to 203 patients who underwent TKA between 2009 and 2016 at the University of Illinois. We utilized health records to document age, gender, body mass index (BMI), and comorbidities. First, we compared the descriptive variables between the satisfied and dissatisfied groups. We then performed multivariate linear regression and multiple logistic regression to assess the predictive value of the questions in the Van Onsem et al. model. The true satisfaction rate in our study was 65%. The Van Onsem et al. model predicted a satisfaction rate of 70%. The scatter plot of predicted satisfaction score versus observed satisfaction score showed poor agreement between actual satisfaction and predicted satisfaction. Comparing satisfied and dissatisfied groups, there was a significant difference with respect to pain prior to surgery and BMI. The validity of the Van Onsem et al. prediction tool was not supported. While the predicted satisfaction rate was near the measured satisfaction rate, the model misidentified which patients were likely to be satisfied. Preoperative variables including pain, anxiety/depression, and a patient's ability to control pain symptoms showed potential for inclusion in future prediction models. LEVEL OF EVIDENCE: Level III, developing a decision model.

Duration of symptoms is associated with conditioned pain modulation and somatosensory measures in knee osteoarthritis.

Impaired descending pain inhibition has been linked to chronic pain and poorer patient outcomes. Vibration perception threshold (VPT) has also been observed and linked to radiographic stage of OA. However, it is not known how duration of symptoms may influence these neurophysiological measures. Our purpose was to evaluate the relationship between duration of symptoms and conditioned pain modulation (CPM), a measure of descending pain inhibition, and VPT, and to determine whether these relationships differed in men and women seeking orthopedic care. We evaluated 18 men and 27 women with moderate to severe knee OA. We assessed CPM using a submaximal-effort tourniquet test: Pressure pain threshold (PPT) at the symptomatic knee was evaluated before and after a noxious stimulus. CPM impairment was indicated by a ratio of pre-to-post stimulus PPT ≥1. VPT was assessed using a biothesiometer at the medial femoral condyle. We used chi-square, t-tests and Pearson correlations to address study questions. 72% of men, but only 44% of women had CPM impairment. Duration of symptoms was associated with CPM impairment in women (R = 0.566, p = 0.003) but not men (R = 0.366, p = 0.135). Duration of symptoms was also associated with VPT in both men (R = 0.580, p = 0.012) and women (R = 0.406, p = 0.039). These results suggest that longer duration of knee OA may predict more severe pain sensitization and that important sex differences exist in descending pain inhibition in people with chronic knee OA that may affect disease and course of treatment in male and female patients. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

A Case Report of a Radial Nerve Palsy Following Uncomplicated Total Hip Arthroplasty.

INTRODUCTION: Nerve injury is a known complication of total hip arthroplasty (THA), but it is most commonly seen in the lower extremities. There is, however, minimal discussion about the incidence of upper extremity nerve palsies, specific to the radial nerve, during THA for a patient in the lateral decubitus position. The radial nerve can be injured while in the lateral decubitus position due to poor positioning of the posterior part of the humerus onto the hard surgical table causing compression of the nerve. In THA, this is significant due to the lateral decubitus position being the primary position for the patient in posterior and lateral approaches. We report a case of radial nerve palsy following uncomplicated THA in the lateral decubitus position. CASE REPORT: A 49-year-old male presenting with symptoms of the left radial nerve palsy on post-operative day number one from a right (contralateral) THA. The patient has a body mass index of 22.15 and was undergoing a right THA with a posterior approach. He was placed in the lateral decubitus position with an axillary roll in place for approximately 2 h and 45 min. Occupational therapy, orthopedics, and electromyography were used to evaluate the patient in the post-operative time for his radial nerve palsy. CONCLUSION: Our case report demonstrates a rare nerve palsy complication that can be associated with positioning in THA surgeries. Knowledge of this complication can be used to avoid pressure points in future THA surgeries in the lateral decubitus position.

Hip abductor strength and fatigue are associated with activity levels more than 1 year after total hip replacement.

Despite improvements in pain and function, people who undergo total hip arthroplasty (THR) may not always return to desired levels of physical activity (PA). The factors associated with low activity levels are not fully understood. Abductor weakness and fatigue have both been proposed as factors that limit activity in older adults or people with hip osteoarthritis, but have not been investigated after THR. We hypothesized that abductor weakness and fatigue are associated with lower activity levels in people who have undergone a THR and that fatigue mediates the association between abductor strength and activity. We evaluated 16 subjects (24 ± 10 months post-THR; age 56.8 ± 8.4 yrs; BMI 31 ± 7 kg/m2 ). Fatigue was assessed using the PROMIS fatigue short-form 7a. Peak isometric hip abductor torque was assessed using a dynamometer with subjects in a sidelying position. We assessed activity level using the UCLA activity score. We used Pearson correlations to explore the associations among the variables. Next we used a three-step linear regression procedure to test whether or not fatigue acted as a mediator between abductor torque and UCLA activity scores. Higher abductor torque was associated with less fatigue (R2 = 0.275; p = 0.037) and with higher UCLA scores (R2 = 0.488, p = 0.003). Higher fatigue was associated with lower UCLA scores (R2 = 0. 307, p = 0.017), however there was no evidence of mediation. This suggests that addressing both abductor strength and fatigue may increase physical activity. Statement of Clinical Significance: Fatigue and abductor weakness should be evaluated in sedentary THR patients presenting for long-term follow-up. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1519-1525, 2018.