Patient satisfaction and patient-reported outcomes do not vary by BMI class in total hip arthroplasty

PURPOSE

Obesity has been identified as a risk factor for postoperative complications in patients undergoing total hip arthroplasty (THA). This study aimed to investigate patient-reported outcomes, pain, and satisfaction as a function of body mass index (BMI) class in patients undergoing THA.

METHODS

1736 patients within a prospective observational study were categorized into BMI classes. Pre- and postoperative Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR), satisfaction, and pain scores were compared by BMI class using one-way ANOVA.

RESULTS

Healthy weight patients reported the highest preoperative HOOS JR (56.66 ± 13.35) compared to 45.51 ± 14.45 in Class III subjects. Healthy weight and Class III patients reported the lowest (5.65 ± 2.01) and highest (7.06 ± 1.98, p < 0.0001) preoperative pain, respectively. Changes in HOOS JR scores from baseline suggest larger improvements with increasing BMI class, where Class III patients reported an increase of 33.7 ± 15.6 points at 90 days compared to 26.1 ± 17.1 in healthy weight individuals (p = 0.002). Fewer healthy weight patients achieved the minimal clinically important difference (87.4%) for HOOS JR compared to Class II (96.5%) and III (94.7%) obesity groups at 90 days postoperatively. Changes in satisfaction and pain scores were largest in the Class III patients. Overall, no functional outcomes varied by BMI class postoperatively.

CONCLUSION

Patients of higher BMI class reported greater improvements following THA. While risk/benefit shared decision-making remains a personalized requirement of THA, this study highlights that utilization of BMI cutoff may not be warranted based on pain and functional improvement.

A Retrospective Study on the Feasibility of Using Low-burden Patient-reported Pain Scores to Track Recovery and Outcomes After Total Joint Replacement

Background

Patients undergo total joint arthroplasty to improve function and resolve pain. Patient-reported outcome measures (PROMs) are often sought to determine the success of total joint arthroplasty but are time-consuming and patient response rates are often low. This study sought to determine whether pain numeric rating scores (NRSs) were associated with PROMs and objective mobility outcomes.

Methods

This is a retrospective review of data in patients who utilized a smartphone-based care management application prior to and following total joint arthroplasty. NRS, Hip Disability and Osteoarthritis Outcome Score, Joint Replacement and Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, and objective mobility data (step counts, gait speed, and gait asymmetry) were collected preoperatively and at 30 and 90 days postoperatively. Quantile regression was performed to evaluate the correlations between NRS and PROMs.

Results

Total knee arthroplasty patients reported higher NRS than total hip arthroplasty patients postoperatively. NRS was significantly correlated with gait speed preoperatively and at 30 and 90 days postoperatively on quantile regression. Gait asymmetry was significantly associated with NRS at 30 days postoperatively. Regression results suggested significant correlations between NRS and PROMs scores; Hip Disability and Osteoarthritis Outcome Score, Joint Replacement, -0.46 (95% confidence interval: -0.48 to -0.44, P < .001) and Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, -0.38 (95% confidence interval: -0.40 to -0.36, P < .001).

Conclusions

NRS is correlated with both objective and subjective measures of function in patients undergoing arthroplasty. Simple pain ratings may be a valid measurement to help predict functional outcomes when collection of traditional PROMs is not feasible.

Impact of Chronic Opioid Use on Postoperative Mobility Recovery and Patient-Reported Outcomes: A Propensity-Matched Study

BACKGROUND

Opioid use prior to total joint arthroplasty may be associated with poorer postoperative outcomes. However, few studies have reported the impact on postoperative recovery of mobility. We hypothesized that chronic opioid users would demonstrate impaired objective and subjective mobility recovery compared to nonusers.

METHODS

A secondary data analysis of a multicenter, prospective observational cohort study in which patients used a smartphone-based care management platform with a smartwatch for self-directed rehabilitation following hip or knee arthroplasty was performed. Patients were matched 2:1 based on age, body mass index, sex, procedure, Charnley class, ambulatory status, orthopedic procedure history, and anxiety. Postoperative mobility outcomes were measured by patient-reported ability to walk unassisted at 90 days, step counts, and responses to the 5-level EuroQol-5 dimension 5-level, compared by Chi-square and student's t-tests. Unmatched cohorts were also compared to investigate the impact of matching.

RESULTS

A total of 153 preoperative chronic opioid users were matched to 306 opioid-naïve patients. Age (61.9 ± 10.5 versus 62.1 ± 10.3, P = .90) and sex (53.6 versus 53.3% women, P = .95) were similar between groups. The proportion of people who reported walking unassisted for 90 days did not vary in the matched cohort (87.8 versus 90.7%, P = .26). Step counts were similar preoperatively and 1-month postoperatively but were lower in opioid users at 3 and 6 months postoperatively (4,823 versus 5,848, P = .03). More opioid users reported moderate to extreme problems with ambulation preoperatively on the 5-level EuroQol-5 dimension 5-level (80.6 versus 69.0%, P = .02), and at 6 months (19.2 versus 9.3%, P = .01).

CONCLUSIONS

Subjective and objective measures of postoperative mobility were significantly reduced in patients who chronically used opioid medications preoperatively. Even after considering baseline factors that may affect ambulation, objective mobility metrics following arthroplasty were negatively impacted by preoperative chronic opioid use.

Completion of Patient-Reported Outcome Measures Improved With Use of a Mobile Application in Arthroplasty Patients: Results From a Randomized Controlled Trial

BACKGROUND

The collection of patient-reported outcome measures (PROMs) has historically been reported as costly and time-consuming, with low compliance rates that may impact reimbursement. Little research has reported the effects of mobile applications to support PROMs collection following arthroplasty.

METHODS

Secondary analysis of data from a multicenter randomized controlled trial was performed. Patients undergoing knee and hip arthroplasty were randomized to utilize a smartphone-based care management platform (app) for self-directed rehabilitation and completed joint-specific PROMs (Hip Dysfunction and Osteoarthritis Outcome Score, Joint Replacement or Knee Injury and Osteoarthritis Score, Joint Replacement) via the application at prescribed intervals or on paper during clinic visits. Control patients received practice standard of care, and completed PROMs via emailed hyperlink or during clinic visits following lower limb arthroplasty. Overall, 455 patients underwent knee arthroplasty procedures (245 control, 210 app group) and 380 underwent total hip arthroplasty (206 control, 174 app group). Compliance with expected PROMs completion was calculated through one year postoperatively.

RESULTS

Compliance was higher in the app group preoperatively in both knee (98.1 versus 86.9%, P < .0001) and hip cohorts (96.0 versus 88.4%, P = .008), and postoperatively, including at one year (knees, 72.2 versus 53.7%, P < .0001; hips, 71.1 versus 49.2%, P < .0001). On log-binomial regressions, intervention arm was the strongest predictor of completion of all PROMs, where app users undergoing knee (Relative Risk 2.039, 95% confidence interval (CI) 1.595 to 2.607, P < .000) and hip arthroplasty (2.268 95% CI 1.742 to 2.953, P < .0001) were more likely to be compliant at all timepoints. The majority of patients in the app group, including those over 65 years of age, completed PROMs using the application as opposed to paper methods.

CONCLUSIONS

A smartphone mobile application that engages patients during recovery after knee and hip joint arthroplasty improved compliance with completion of preoperative and postoperative PROMs compared to other electronic and paper methods.

Early post-operative walking bouts are associated with improved gait speed and symmetry at 90 days

INTRODUCTION

There is a paucity of literature on optimal patterns of daily walking following joint arthroplasty, which are now evaluated with consumer technologies like smartphones, and can enhance our understanding of post-operative mobility. When smartphone-recorded, daily walking patterns are captured, qualities of gait-recovery such as gait speed or symmetry can be analyzed in real-world environments.

RESEARCH QUESTION

Are the daily distribution of walking bouts in the early post-operative period associated with 90-day gait quality measures following hip and knee arthroplasty?

METHODS

Gait data was collected passively using a smartphone-based care management platform in patients undergoing hip and knee arthroplasty. As recorded via subjects' free-living smartphone-collected gait bouts, data were investigated as a function of the walking session length and were used to create a ratio to the total time logging bouts, representing the fraction of walking performed during a single session per day (aggregation score). Quantile regression was performed to evaluate the association between early walking session lengths or aggregation score at 30 days post-operatively and the gait-sampled speed and asymmetry of walking at 90 days.

RESULTS

In total, 2255 patients provided evaluable data. The walking session length at 30 days was positively associated with 90-day mean gait speed across procedure types where quantile regression coefficients ranged from 0.11 to 0.17. In contrast, aggregation score was negatively associated with gait speed at 90 days, with coefficients ranging from -0.18 to -0.12.

SIGNIFICANCE

The duration and frequency of walking bouts was associated with recovery of gait speed and symmetry following lower limb arthroplasty. The findings may help clinicians design walking protocols that are associated with improved gait metrics at 3 months.

Outcomes Vary by Pre-Operative Physical Activity Levels in Total Knee Arthroplasty Patients

Physical activity (PA) is suggested to reduce osteoarthritis pain; however, it may be avoided by patients requiring arthroplasty. Our goal was to investigate objective and patient-reported outcomes as a function of pre-operative PA levels in patients undergoing total knee arthroplasty (TKA). A total of 1941 patients enrolled in a multicenter prospective cohort study investigating a smartphone-based care management platform for self-directed rehabilitation underwent TKA and were included in the analysis. Activity was categorized based on the cohort's step count quartiles into low, moderate, and high pre-operative PA. Pre-operative and post-operative pain, EQ5D5L, KOOS JR, and step counts were compared by ANOVA according to activity group. Pre-operative pain scores increased with the decreasing activity level (all, p < 0.05) and were most improved post-operatively in the low PA group. High PA patients demonstrated the smallest improvements in EQ-5D-5L and KOOS JR. Low and moderate PA patients increased physical activity by three months, reaching 176% and 104% of pre-operative steps; high PA patients did not return to full step counts by one year post-operatively. Patients undergoing TKA who present with higher levels of physical activity report lower levels of pain and higher function pre-operatively but appreciate less improvement up to one year post-operatively. These results may be helpful in appropriate counseling of patient expectations before TKA.

Multicenter, prospective cohort study: immediate postoperative gains in active range of motion following robotic-assisted total knee replacement compared to a propensity-matched control using manual instrumentation

BACKGROUND

Range of motion (ROM) following total knee replacement (TKR) has been associated with patient satisfaction and knee function, and is also an early indicator of a successful procedure. Robotic-assisted TKR (raTKR) is considered to reproduce more precise resections, and, as a result, may be associated with improved early patient satisfaction compared to manual TKR (mTKR). The purpose of this study was to evaluate the early postoperative active ROM (aROM) between raTKR and mTKR.

METHODS

A total of 216 mTKR patients were propensity-matched, in terms of age, gender, comorbidities, and BMI, to 216 raTKR cases. Intraoperative and immediate postoperative adverse events were collected. Knee flexion and extension aROM were measured preoperatively and at one- and three months after operation.

RESULTS

Changes in flexion aROM were significantly greater in raTKR vs. mTKR at one- (6.9°, 95% CI: 3.5, 10.4°) and three months (4.9°, 95% CI: 2.1, 7.7°). Flexion aROM was greater at three postoperative months compared to preoperative aROM only in the raTKR group, and raTKR patients had higher odds of achieving ≥ 90° of flexion at one month after operation (OR: 2.15, 95% CI: 1.16, 3.99). There were no significant differences between groups in intraoperative (P > 0.999) or postoperative adverse events.

CONCLUSIONS

Compared with mTKR, raTKR resulted  in less loss of aROM immediately after operation and a faster recovery of aROM within three months after operation.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT# 03737149).

Stepping Beyond Counts in Recovery of Total Hip Arthroplasty: A Prospective Study on Passively Collected Gait Metrics

Gait quality parameters have been used to measure recovery from total hip arthroplasty (THA) but are time-intensive and previously could only be performed in a lab. Smartphone sensor data and algorithmic advances presently allow for the passive collection of qualitative gait metrics. The purpose of this prospective study was to observe the recovery of physical function following THA by assessing passively collected pre- and post-operative gait quality metrics. This was a multicenter, prospective cohort study. From six weeks pre-operative through to a minimum 24 weeks post-operative, 612 patients used a digital care management application that collected gait metrics. Average weekly walking speed, step length, timing asymmetry, and double limb support percentage pre- and post-operative values were compared with a paired-sample t-test. Recovery was defined as the post-operative week when the respective gait metric was no longer statistically inferior to the pre-operative value. To control for multiple comparison error, significance was set at p < 0.002. Walking speeds and step length were lowest, and timing asymmetry and double support percentage were greatest at week two post-post-operative (p < 0.001). Walking speed (1.00 ± 0.14 m/s, p = 0.04), step length (0.58 ± 0.06 m/s, p = 0.02), asymmetry (14.5 ± 19.4%, p = 0.046), and double support percentage (31.6 ± 1.5%, p = 0.0089) recovered at 9, 8, 7, and 10 weeks post-operative, respectively. Walking speed, step length, asymmetry, and double support all recovered beyond pre-operative values at 13, 17, 10, and 18 weeks, respectively (p < 0.002). Functional recovery following THA can be measured via passively collected gait quality metrics using a digital care management platform. The data suggest that metrics of gait quality are most negatively affected two weeks post-operative; recovery to pre-operative levels occurs at approximately 10 weeks following primary THA, and follows a slower trajectory compared to previously reported step count recovery trajectories.

Stepping beyond Counts in Recovery of Total Knee Arthroplasty: A Prospective Study on Passively Collected Gait Metrics

Advances in algorithms developed from sensor-based technology data allow for the passive collection of qualitative gait metrics beyond step counts. The purpose of this study was to evaluate pre- and post-operative gait quality data to assess recovery following primary total knee arthroplasty. This was a multicenter, prospective cohort study. From 6 weeks pre-operative through to 24 weeks post-operative, 686 patients used a digital care management application to collect gait metrics. Average weekly walking speed, step length, timing asymmetry, and double limb support percentage pre- and post-operative values were compared with a paired-samples t-test. Recovery was operationally defined as when the respective weekly average gait metric was no longer statistically different than pre-operative. Walking speed and step length were lowest, and timing asymmetry and double support percentage were greatest at week two post-operative (p < 0.0001). Walking speed recovered at 21 weeks (1.00 m/s, p = 0.063) and double support percentage recovered at week 24 (32%, p = 0.089). Asymmetry percentage was recovered at 13 weeks (14.0%, p = 0.23) and was consistently superior to pre-operative values at week 19 (11.1% vs. 12.5%, p < 0.001). Step length did not recover during the 24-week period (0.60 m vs. 0.59 m, p = 0.004); however, this difference is not likely clinically relevant. The data suggests that gait quality metrics are most negatively affected two weeks post-operatively, recover within the first 24-weeks following TKA, and follow a slower trajectory compared to previously reported step count recoveries. The ability to capture new objective measures of recovery is evident. As more gait quality data is accrued, physicians may be able to use passively collected gait quality data to help direct post-operative recovery using sensor-based care pathways.

Is sequential bilateral robotic total knee arthroplasty a safe procedure? A matched comparative pilot study

INTRODUCTION

To our knowledge, no papers have reported the results of robotic-assisted surgery for sequential bilateral Total Knee Arthroplasty (TKA). Indeed, sequential bilateral TKA present several benefits, as one single anesthesia, surgical episode, hospitalization, and rehabilitation. The purpose of our study was to evaluate peri-operative outcomes and compare the complication rates, clinical outcomes, and implant positioning of sequential bilateral TKA performed with a robotic-assisted system versus a conventional technique.

MATERIALS AND METHODS

All patients who underwent a sequential bilateral robotic-assisted primary TKA (raTKA) in our institution between November 2019 and February 2021 were included. Twenty patients met the inclusion criteria and were matched with 20 sequential bilateral TKA performed with a conventional technique. The two groups were comparable for the demographic data and the preoperative parameters, including preoperative anticoagulation and ASA score. The minimum follow-up was 6 months.

RESULTS

The operative time was significantly longer in the robotic group (< 0.0001), with a mean additional time of 29 min. There was no significant difference between both groups for postoperative blood loss, rate of blood transfusion, or postoperative pain. The average length of stay was 5 days. There was one early complication in the robotic group due to the tibial trackers. The functional outcomes were similar between both groups, except for the functional KSS score, which was better at 6 months in the robotic group (p < 0.0001). The restoration of the knee alignment and the distal femoral anatomy were significantly better in the robotic group than in the conventional group.

CONCLUSIONS

Despite a longer operative time, the peri-operative parameters of sequential bilateral TKA were similar between robotic and conventional techniques. Further, sequential bilateral raTKA was at least as safe as a conventional technique, without additional risk of medical complications.

Immediate Postoperative Improvement in Gait Parameters following Primary Total Knee Arthroplasty Can Be Measured with an Insole Sensor Device

Total knee arthroplasty (TKA) improves the quality of life in those suffering from debilitating arthritis of the knee. However, little is known about the influence of TKA on restoring physical function. Prior studies have used artificial means, such as instrumented treadmills, to assess physical function after TKA. In this study an insole sensor device was used to quantify parameters of gait. The purpose of this study was to evaluate the ability of a wearable insole sensor device to measure immediate postoperative gait parameters at 2 weeks and 6 weeks following primary TKA and to determine if the device was suitable and sensitive enough to identify and measure potentially subtle changes in these measures at these early postoperative time periods. Twenty-nine patients with unilateral TKA, without contralateral knee pain, and aid-free walking before surgery were evaluated. An insole force sensor measured the postoperative parameters while walking a distance of 40 m on level ground at 2 and 6 weeks after TKA. The loading rate of the operated lower extremity was an average of 68.7% of the contralateral side at 2 weeks post-surgery and increased to 82.1% at 6 weeks post-surgery (p < 0.001). The mean gait speed increased from 0.75 to 1.02 m/s, (p < 0.001) and cadence increased from 82.9 to 99.9 steps/min (p < 0.001), while the numeric pain scale at rest decreased from 3.5/10 to 2.2/10, (p < 0.001) and the pain while walking from 3.9/10 to 2.4/10, (p < 0.001) from 2 to 6 weeks post-surgery. A significant improvement in gait parameters is detectable in the first 6 weeks after surgery with the use of a wearable insole device. As the gait speed and cadence increase and the VAS pain level decreases, the loading rate and average peak force begin to normalize. This device may allow for early gait analysis and have potential clinical utility in detecting early differences in patients' functional status following TKA.

The initial learning curve for the ROSA® Knee System can be achieved in 6-11 cases for operative time and has similar 90-day complication rates with improved implant alignment compared to manual instrumentation in total knee arthroplasty

Purpose

The purpose of this study was to determine the learning curve for total operative time using a novel cutting guide positioning robotic assistant for total knee arthroplasty (raTKA). Additionally, we compared complications and final limb alignment between raTKA and manual TKA (mTKA), as well as accuracy to plan for raTKA cases.

Methods

We performed a retrospective cohort study on a series of patients (n = 180) that underwent raTKA (n = 90) using the ROSA Total Knee System or mTKA (n = 90) by one of three high-volume (> 200 cases per year) orthopaedic surgeons between December 2019 and September 2020, with minimum three-month follow-up. To evaluate the learning curve surgical times and postoperative complications were reviewed.

Results

The cumulative summation analysis for total operative time revealed a change point of 10, 6, and 11 cases for each of three surgeons, suggesting a rapid learning curve. There was a significant difference in total operative times between the learning raTKA and both the mastered raTKA and mTKA groups (p = 0.001) for all three surgeons combined. Postoperative complications were minimal in all groups. The proportion of outliers for the final hip-knee-ankle angle compared to planned was 5.2% (3/58) for the mastered raTKA compared to 24.1% (19/79) for mTKA (p = 0.003). The absolute mean difference between the validated and planned resections for all angles evaluated was < 1 degree for the mastered raTKA cases.

Conclusion

As the digital age of medicine continues to develop, advanced technologies may disrupt the industry, but should not disrupt the care provided. This cutting guide positioning robotic system can be integrated relatively quickly with a rapid initial learning curve (6-11 cases) for operative times, similar 90-day complication rates, and improved component positioning compared to mTKA. Proficiency of the system requires additional analysis, but it can be expected to improve over time.

Level of evidence

Level III Retrospective Therapeutic Cohort Study.

Outcomes of Rotating-hinge Total Knee Arthroplasty Following Complex Primary and Revision Total Knee Arthroplasty

In complex primary and revision total knee arthroplasty (TKA), rotating-hinge TKA (RH-TKA) prostheses play an important role. Compared to early fixed-hinge knee designs, new implants that include rotating platforms and improved hinge constructs may offer improvements in both survival and clinical outcomes. We sought to evaluate early survival following complex primary and revision TKA with a rotating-hinge knee prosthesis. We retrospectively reviewed a consecutive series of patients (n=47, 48 knees) who underwent revision TKA using an RH-TKA system. The mean age was 73 years (range, 37 - 86). The mean body mass index was 29 (range, 16.3 - 45.9) and the median ASA score was 3 (IQR, 2 - 3). As mortality was high, we performed a Kaplan-Meier analysis to evaluate survival, with death as failure. The median follow-up was 2.5 years (range, 0.07 - 9.8). Revision-free survival was 97% at a median 2.5 years of follow-up. Overall mortality was 46% (17/37) and survival free from death was 69% (49% - 82%) at a median of 2.5 years. Most reoperations were due to infection (5/12), following by wound-related complications (2/12) and hematomas (2/12). A high postoperative complication rate and mortality are evident in TKA using a hinged knee prosthesis in complex revision TKA. If the indication and surgical technique are matched to the complexity of the case, this type of implant offers a feasible salvage procedure.

Higher incidence of manipulation under anesthesia following TKA associated with the periarticular infiltration of a liposomal bupivacaine cocktail compared to a modified Ranawat cocktail

BACKGROUND

The purpose of this study was to compare the frequency of postoperative stiffness requiring manipulation under anesthesia (MUA) before and after switching from the intraoperative use of liposomal bupivacaine (LB).

METHODS

This was an institutional review board (IRB)-exempt retrospective cohort study (IRB#71733) on all patients who underwent primary total knee arthroplasty (TKA) by a single surgeon between April 2016 and December 2017. We compared 169 knees that received LB group to 167 knees that received a modified Ranawat cocktail (MR group). Perioperative care pathways remained consistent during the study period, as were requirements for MUA which included flexion range of motion below approximately 90 at 6-12 weeks. To compare the incidence of MUA between the groups, a population-averaged Poisson regression analysis was used.

RESULTS

The two groups were similar, with mean age of 63 (range 31-91) in the LB group and 64 (range 42-84) in the MR group, a preponderance of females in both groups (p = 0.866), similar preoperative knee flexion between groups (p = 0.162), and similar Patient-Reported Outcomes Measurement Information System scores. The frequency of MUA, however, was significantly lower in the MR group (LB: 7.7% [95% CI 3.7-12%] vs. MR: 2.4% [95% CI <1-4.7%] [IRR 3.2, 95% CI 1.08-9.76, p . 0.037]).

CONCLUSIONS

In summary, this is a novel report of a potentially previously unrecognized increased incidence of MUA associated with the use of LB compared with a MR cocktail. Given no other notable changes to the perioperative care or MUA thresholds following TKA, the reasons for these findings are unclear but deserve additional investigation.

A potential need for surgeon consensus: Cementation techniques for total knee arthroplasty in orthopedic implant manufacturers' guidelines lack consistency

AIM

Given recent concerns regarding the influence of different cements and implants on the rate of aseptic failures in total knee arthroplasty (TKA), we wondered if cementation technique could play a role. The primary aim of this review was to collect and compare the surgeon education materials from eight orthopedic implant manufacturers to evaluate the manufacturers' recommended cementation technique in TKA and identify if there was any consistency in these readily available guides as to the best practices of cementation of their implants.

MATERIALS AND METHODS

We reviewed contemporary surgeon education guidelines for all TKA systems available from eight manufacturers. Variables included: cement type, batches prepared, surface preparation prior to application, cleaning and/or drying the bone surface, mixing the cement, the waiting phase after the cement has been mixed prior to application, pressurizing the cement, location of cement application, and the curing time. Data were recorded and organized for qualitative comparisons.

RESULTS

We identified a total of 43 guides covering 38 implants from eight different manufacturers. There were 41 surgical technique guides and two general brochures regarding cementation techniques available from the manufacturers. Even within the manufacturers' own guidelines for the different implants, there was a wide variety of differing guidelines on many aspects of the cementation technique.

CONCLUSION

There is clearly no consensus for a preferred cementation technique both within and among manufacturers' surgeon education materials regarding tibial baseplate cementation during TKA. Efforts may be needed to identify a best-practice cementation technique in an effort to reduce the number of TKA failures associated with aseptic loosening.

Socioeconomic Status May Not Be a Risk Factor for Periprosthetic Joint Infection

BACKGROUND

Periprosthetic joint infection (PJI) is a devastating complication after total joint arthroplasty, carrying significant economic and personal burden. The goal of this study is to use an established database to analyze socioeconomic variables and assess their relationship to PJI. Additionally, we sought to evaluate whether socioeconomic factors, along with other known risk factors of PJI, when controlled for in a statistical model affected the familial risk of PJI.

METHODS

With approval from our Institutional Review Board we performed a population-based retrospective cohort study on all primary total joint arthroplasty cases of the hip or knee (n = 85,332), within a statewide database, between January 1996 and December 2013. We excluded 9854 patients due to age <18 years, missing data, history of PJI prior to index procedure, and no evidence of 2-year follow-up (excluding those with PJI). Cases that developed PJI following the index procedure (n = 2282) were compared to those that did not (n = 73,196).

RESULTS

After adjusting for covariates, patients with Medicaid as a primary payer were at greater risk for experiencing PJI (relative risk 1.40, 95% confidence interval [CI] 1.08-1.82, P = .01). There was no difference in risk between the groups associated with education level or median household income (all, P > .05). First-degree relatives of patients who develop PJI (hazard ratio 1.66, 95% CI 1.23-2.24, P = .001) and first-degree and second-degree relatives combined (hazard ratio 1.39, 95% CI 1.09-1.77, P = .007) were at greater risk despite controlling for the above socioeconomic factors.

CONCLUSION

Our study provides further support that genetic factors may underlie PJI as we did observe significant familial risk even after accounting for socioeconomic factors and payer status. We did not find a correlation between education level or household income and PJI; however, Medicaid payees were at increased risk. Continued study is needed to define a possible heritable disposition to PJI in an effort to optimize treatment and possibly prevent this complication.

Revisiting the role of isolated polyethylene exchange for aseptic failures in total knee arthroplasty

BACKGROUND

Controversy continues to exist regarding the advisability of isolated polyethylene exchange (IPE) following total knee arthroplasty (TKA) for aseptic indications. We sought to compare the difference in the cumulative incidence of reoperation after IPE specifically for aseptic failure and to evaluate risk factors for failure.

METHODS

We performed a retrospective cohort study of 122 knees revised for aseptic failure. Reasons for IPE in aseptic knees included: instability, polyethylene wear, arthrofibrosis, patella fracture, patellar resurfacing, patellar maltracking, extensor mechanism failure, patellectomy, and a custom polyethylene for correction of valgus deformity. The relatively high rate of mortality warranted a competing risk model to evaluate the cumulative incidence reoperation. Follow-up time was defined by years from IPE to date of reoperation or last follow-up. Generalized estimating equations were used for comparisons.

RESULTS

Our analysis demonstrated an 87% (95% CI, 78-92%) survivorship free of reoperation at five years. Re-revision was secondary to aseptic failure, infection, and patellar malalignment. IPE for polyethylene wear was found to be protective and less likely to require reoperation (SHR 0.121 95% CI: 0.016-0.896, p = 0.039).

CONCLUSIONS

The current study suggests that when done for carefully selected indications, IPE may be an acceptable procedure and helpful alternative for aseptic TKA revisions, particularly when the pre-operative diagnosis is polyethylene wear. This is in contrast to prior reports and may represent a need to re-visit the role of isolated polyethylene exchange.

Ten-Year Survivorship, Patient-Reported Outcomes, and Satisfaction of a Fixed-Bearing Unicompartmental Knee Arthroplasty

Background

We sought to determine the 10-year survivorship and reasons for revision for a fixed-bearing unicompartmental knee arthroplasty (UKA) design. In addition, we report on patient-reported outcomes and satisfaction and compare results of medial vs lateral compartment UKA and cemented vs cementless UKA with the same design.

Methods

We performed a retrospective cohort study on a single-surgeon case series using a single fixed-bearing UKA design in 158 consecutive patients who underwent 177 UKA procedures between July 2000 and December 2010. Cases missing follow-up within the last year, clinically or via telephone, were excluded (n = 17, 10%). A cumulative incidence competing risk model was used to evaluate the cumulative incidence of failure.

Results

Cumulative incidence of revision at a mean follow-up of 10 years was 13%. The majority of revisions (43%, 10/23) were for aseptic tibial component loosening, followed by progression of osteoarthritis (5/23, 22%). All Patient Reported Outcomes Measurement Information System measures demonstrated mean T-scores within one standard deviation from the US population norm. The mean Knee Injury and Osteoarthritis Outcome Score for Joint Replacement was 96.9 (range, 40-100). The mean pain score was 3.8 (range, 0-8). Eighty-six percent of patients were satisfied with the UKA.

Conclusions

At 10-year follow-up, the most common causes for revision were aseptic tibial loosening and adjacent compartment knee arthroplasty, and similar results were found for medial vs lateral compartment and for cemented vs cementless UKA. Surgeons should consider these findings for future UKA designs, and this represents the first study reporting on survivorship and outcomes of this specific UKA design.

Advantages of an Anterior-Based Muscle-Sparing Approach in Transitioning From a Posterior Approach for Total Hip Arthroplasty: Minimizing the Learning Curve

BACKGROUND

Enthusiasm for anterior-based approaches for total hip arthroplasty (THA) continues to increase but there is concern for increased complications during the learning curve period associated. This study aimed to investigate if there was a difference in perioperative variables, intraoperative and immediate postoperative complications, or patient-reported outcomes when transitioning from a mini-posterior approach (mPA) to an anterior-based muscle-sparing (ABMS) approach for THA.

METHODS

Retrospective cohort study on the first 100 primary THA cases (n = 96 patients) of the senior author (August 2016 to August 2017) using the ABMS approach. These cases were compared to primary THA cases done the year prior (July 2015 to July 2016, n = 91 cases in 89 patients) using an mPA. Data were extracted and analyzed via gamma regression with robust standard errors and using generalized estimating equation regression.

RESULTS

We found no difference in the estimated blood loss (P = .452) and surgical time (P = .564) between the cohorts. The ABMS cases had a slightly shorter length of stay (P = .001) with an adjusted mean length of stay of 1.53 days (95% confidence interval 1.4-1.6) compared to 1.85 days (95% confidence interval 1.8-1.9) in the mPA cases. There was no difference in the frequency of immediate postoperative complications (all, P > .05). There was no difference in the adjusted mean change in patient-reported outcomes (all P > .05). In the ABMS group, there was no difference in surgical time or physical function computerized adaptive test between the first 20 cases (reference) and each subsequent group of 20 cases (all P > .05).

CONCLUSION

This study demonstrates no associated learning curve for an experienced senior surgeon when switching routine THA approach from mPA to ABMS. We advise careful interpretation of our results, as they may not apply to all surgeons and practices.

LEVEL OF EVIDENCE

Level III Therapeutic Study: retrospective comparative study.

Patients with Type-1 Diabetes Are at Greater Risk of Periprosthetic Joint Infection: A Population-Based, Retrospective, Cohort Study

BACKGROUND

The effect of diabetes type on the risk of periprosthetic joint infection is not well documented. We hypothesized that patients with diabetes mellitus type 1 would be at greater risk for periprosthetic joint infection than those with diabetes mellitus type 2 and that a history of diabetic complications would be associated with an increased risk of periprosthetic joint infection.

METHODS

We performed a retrospective cohort study, within a statewide database, on all adult patients who underwent hip or knee arthroplasty, with follow-up of ≥2 years, from 1996 to 2013. Of the 75,478 patients included, 1,668 had type-1 diabetes and 18,186 had type-2 diabetes. Risk factors were calculated using Cox regression, adjusting for siblings and stratified by age. Logistic regression was used to analyze the effect of diabetic complications on the risk of periprosthetic joint infection, controlling for other known risks for periprosthetic joint infection.

RESULTS

There was no difference in age or sex between groups (p > 0.05). The frequency of periprosthetic joint infection in patients without diabetes was 2.6% compared with 4.3% in all patients with diabetes (relative risk, 1.47; p < 0.001). Patients with type-1 diabetes were at a 1.8 times greater risk for periprosthetic joint infection than patients with type-2 diabetes (7% compared with 4%; p < 0.001). The following diabetic complications increased the risk of periprosthetic joint infection: peripheral circulatory disorders (odds ratio [OR], 2.59 [95% confidence interval (CI), 1.70 to 3.94]), ketoacidosis (OR, 2.52 [95% CI, 1.51 to 4.19]), neurological manifestations (OR, 2.33 [95% CI, 1.96 to 2.78]), renal manifestations (OR, 2.15 [95% CI, 1.66 to 2.79]), and ophthalmic manifestations (OR, 1.76 [95% CI, 1.24 to 2.51]). The odds of periprosthetic joint infection increased with each added complication and patients with ≥4 complications were 9 times more likely to have a periprosthetic joint infection than patients with uncomplicated diabetes (OR, 9.47 [95% CI, 4.97 to 18.03]). Overweight and obese patients with type-2 diabetes and underweight patients with type-1 diabetes were at greater risk for periprosthetic joint infection compared with the general population (all p < 0.05).

CONCLUSIONS

Our data showed an increased risk of periprosthetic joint infection in patients with type-1 diabetes compared with those with type-2 diabetes, along with an increasing risk associated with additional diabetic complications. These findings emphasize the need to better understand the medical history of patients with diabetes for more appropriate risk management.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mean Three-Year Survivorship of a New Bicruciate-Retaining Total Knee Arthroplasty: Are Revisions Still Higher Than Expected?

BACKGROUND

Given the need for continued post-market surveillance, especially on novel implants, the present study attempts to determine the 3-year survivorship and patient-reported outcomes of a contemporary bicruciate-retaining total knee arthroplasty design, and to determine if a learning curve existed which could explain previously reported revision rates.

METHODS

We performed a retrospective review on a consecutive series of 141 bicruciate-retaining total knee arthroplasties performed at our institution between May 2013 and October 2015. Thirty-four knees (19%) missing 2-year follow-up were excluded. Mean follow-up was 3 years (range 0.34-4.9). Patients who died (n = 5) or were revised prior to 2 years (n = 6) were included. A Kaplan-Meier analysis was used to evaluate revision-free survival.

RESULTS

Survivorship at 3 years was 88% (82%-93%). Revisions were for isolated tibial loosening (5/19), anterior cruciate ligament (ACL) impingement (3/19), pain (4/19), unknown reasons (3/19), femoral and tibial loosening (2/19), ACL deficiency (1/19), and arthrofibrosis (1/19). The mean physical function computerized adaptive test T-score was 45 units (range 23-63). The mean T-scores for Patient-Reported Outcomes Measurement Information System Global measures were 49 (range 27-68) for physical health, 50 (range 28-68) for mental health, and a median 3 (interquartile range 1-8) on the numeric pain scale.

CONCLUSION

Revision-free survival of 88% at 3 years was lower than existing traditional TKA designs. The primary failure mechanisms were tibial loosening, ACL impingement, and pain. In the setting of higher than anticipated revision rates, despite patient-reported outcomes that are not different than seen in the general population, it is possible that further refinement in implant design or surgical technique may be needed prior to widespread use of this, or similar implant designs.

Correction of mildly dysplastic hips with periacetabular osteotomy demonstrates promising outcomes, achievement of correction goals, and excellent five-year survivorship

AIMS

The aim of this study was to compare patient-reported outcome measures (PROMs), radiological measurements, and total hip arthroplasty (THA)-free survival in patients who underwent periacetabular osteotomy (PAO) for mild, moderate, or severe developmental dysplasia of the hip.

PATIENTS AND METHODS

We performed a retrospective study involving 336 patients (420 hips) who underwent PAO by a single surgeon at an academic centre. After exclusions, 124 patients (149 hips) were included. The preoperative lateral centre-edge angle (LCEA) was used to classify the severity of dysplasia: 18° to 25° was considered mild (n = 20), 10° to 17° moderate (n = 66), and < 10° severe (n = 63). There was no difference in patient characteristics between the groups (all, p > 0.05). Pre- and postoperative radiological measurements were made. The National Institute of Health's Patient Reported Outcomes Measurement Information System (PROMIS) outcome measures (physical function computerized adaptive test (PF CAT), Global Physical and Mental Health Scores) were collected. Failure was defined as conversion to THA or PF CAT scores < 40, and was assessed with Kaplan-Meier analysis. The mean follow-up was five years (2 to 10) ending in either failure or the latest contact with the patient.

RESULTS

There was no significant difference in PROMs for moderate (p = 0.167) or severe (p = 0.708) groups compared with the mild dysplasia group. The numerical pain scores were between 2 and 3 units in all groups at the final follow-up (all, p > 0.05). There was no significant difference (all, p > 0.05) in the proportion of patients achieving target correction for the LCEA between groups. The mean correction was 12° in the mild, 15° in the moderate (p = 0.135), and 23° in the severe group (p < 0.001). Failure-free survival at five years was 100% for mild, 79% for moderate, and 92% for severely dysplastic hips (p = 0.225).

CONCLUSION

Although requiring less correction than hips with moderate or severe dysplasia, we found PAO for mild dysplasia to be associated with promising PROMs, consistent with that of the general United States population, and excellent survivorship at five years. Future studies should compare these results with the outcome after arthroscopy of the hip in patients with mild dysplasia. Cite this article: Bone Joint J 2019;101-B(6 Supple B):16-22.

Randomized controlled trial of a simplified adductor canal block performed for analgesia following total knee arthroplasty

Background and objectives

The objective of the study was to determine if injection of local anesthetic into the vastus medialis and sartorius muscles adjacent to the adductor canal produces sensory changes comparable with adductor canal block (ACB). This could result in a technically easier and potentially safer alternative to ACB.

Methods

In this randomized controlled trial, patients received either ACB (n=20) or a simplified adductor canal (SAC) block performed using a new fenestrated nerve block needle (n=20). The time to perform each block as well as the number of attempts to position the needle were evaluated. A non-inferiority test was used to compare pain scores and opioid requirements for the ACB and the SAC block.

Results

The SAC block was performed more rapidly, with fewer needle passes, and had a higher success rate than the ACB. Three block failures and two vessel punctures were observed in the ACB group, while none of these events occurred in SAC block patients. Analgesia and opioid consumption for patients treated with the SAC block were not inferior to ACB.

Conclusion

The SAC block is technically easier to perform and potentially safer than ACB. This procedure can be performed using easily visible ultrasound landmarks and has the potential for use among a wide range of healthcare providers.

Trial registration number

NCT02786888.

Early outcomes after revision total hip arthroplasty with a modern modular femoral revision stem in 65 consecutive cases

Background

We evaluated the early outcomes, including all-cause revisions, aseptic revisions, and reoperations after revision total hip arthroplasty (THA) using a single modern modular femoral stem design.

Methods

A retrospective cohort study on a consecutive series of 62 patients (65 hips) who underwent revision THA with a modern modular femoral stem system, between January 2011 and October 2015, at a single academic medical center was performed. A cumulative incidence competing risk model was used to evaluate the cumulative incidence of failure with death as the competing risk.

Results

The cumulative incidence rate of all-cause revision THA was 14.5% (95% confidence interval [CI], 6%–24%) at 2 years when accounting for the competing risk of death. The rate of aseptic revisions was 6.8% (95% CI, 0.1%–13%), and the rate of all-cause reoperations was 21.6% (95% CI, 11%–31%). Ten THA cases (15%) underwent re-revision THA for any reason: five for infection and five for aseptic failures. The mean time to re-revision was 1 year (range, 0.04–5.34). Patients with a preoperative Mallory classification of 3 or more were at greater risk for reoperation (sub-hazard rate, 3.84; 95% CI, 1.54–9.53; P = .004).

Conclusions

Although the high incidence of reoperation illustrates the complexity of the revision THA population, particularly related to infection and joint instability, the relatively low rate of aseptic failures, minimal radiographic subsidence, and the lack of modular junctional failures suggest that the use of this modular revision THA system may provide adequate fixation and could be considered as a viable treatment option in the setting of revision THA.

Pinnacle polyethylene liner dissociation: a report of 3 cases

We describe 3 cases of DePuy Pinnacle polyethylene dissociations, their presentations, and treatment. A 34-year-old female with arthritis secondary to dysplasia, a 51-year-old male with avascular necrosis of the femoral head, and a 57-year-old female with osteoarthritis were treated with total hip arthroplasty. Acute nontraumatic polyethylene liner dissociations occurred at 31, 42, and 2 months postoperatively. They were treated with component retention and modular femoral head and liner revision. The 51-year-old male subsequently developed a prosthetic joint infection requiring explant of his components. Although dissociation of polyethylene liners from the DePuy Pinnacle acetabular components is an uncommon complication, this problem may increase in prevalence with longer term follow-up, and vigilance is recommended.

The Recovery Curve for the Patient-Reported Outcomes Measurement Information System Patient-Reported Physical Function and Pain Interference Computerized Adaptive Tests After Primary Total Knee Arthroplasty

BACKGROUND

We sought to characterize the typical recovery in physical function (PF) and pain interference (PI) after TKA using Patient-Reported Outcomes Measurement Information System (PROMIS) patient-reported outcome (PRO) measures.

METHODS

Ninety-one patients were enrolled into an institutional review board -approved prospective observational study. PROs were obtained preoperatively and postoperatively at 6 weeks, 3 months, 6 months, and 1 year. PROs included the PROMIS PF computerized adaptive test (CAT) and the PROMIS PI CAT. Generalized estimating equations were used to evaluate outcomes over time.

RESULTS

There was no difference in the preoperative and 6-week postoperative T-scores for the PF CAT (P = .410). However, all subsequent postoperative T-scores were greater than the preoperative T-score (all, P < 0.05). There was a significant reduction in PI CAT T-scores between the preoperative and all subsequent postoperative T-scores (all, P < .05). A clinically important difference in PF CAT T-scores (β = 5.44, 95% confidence interval 4.10-6.80; P < .001) and PI CAT T-scores (β = -7.46, 95% confidence interval -9.52 to -5.40; P < 0.001) was seen between the preoperative and 3-month postoperative visits. Sixty-three percent of the improvement in PF occurred by 3 months, and 89% had occurred by 6 months. The majority of reduction in PI (68%) occurred by 3 months and 90% had occurred by 6 months.

CONCLUSION

The greatest magnitude of improvement in both PF and PI occurred within the first 3 months. After 6 months, patients might expect modest improvements in PF and mild reductions of PI. Patients and surgeons should use this information for setting expectations, planning for recovery, and improving care.

Press Ganey Outpatient Medical Practice Survey Scores Do Not Correlate With Patient-Reported Outcomes After Primary Joint Arthroplasty

BACKGROUND

Patient delivery of care satisfaction surveys have emerged as instruments to assess the quality of health care at both the hospital and provider levels. We evaluated the correlation between these care satisfaction surveys and patient-reported outcomes (PROs).

METHODS

We reviewed secondary data on 540 patients with 540 random visits who underwent primary total joint arthroplasty between January 2014 and February 2017. The Press Ganey Outpatient Medical Practice Survey was collected from outpatient clinical encounters to measure patient satisfaction with their experience and matched to PRO measures from the same encounter. The PROs evaluated included the Patient-Reported Outcomes Measurement Information System physical function computerized adaptive test, v1.2, and the Patient-Reported Outcomes Measurement Information System Global 10 health survey. In addition to the random selection, we reviewed separate cross-sections of the data including preoperative visits within 90 days of the index procedure, all postoperative visits at least 1 year from the index procedure, and the magnitude of change in PRO scores from preoperative to a minimum 1-year postoperative visit. Data were evaluated using the Spearman correlation coefficient (r_s).

RESULTS

There was little if any correlation between the Press Ganey scores and PROs at all time points evaluated (all, r_s: -0.13 to 0.14). When evaluating knee and hip arthroplasty cases separately, the data demonstrated similar results (all, r_s: -0.33 to 0.18).

CONCLUSION

We found little, if any, correlation between a patient's satisfaction with their care experience and their own perception of physical function and global health measures at all time points evaluated. These data question the utility of these scores as surrogate measures of health care quality, especially when reimbursements become tied to these metrics.

Ten-year survivorship of primary total hip arthroplasty in patients 30 years of age or younger

Aims

For this retrospective cohort study, patients aged ≤ 30 years (very young) who underwent total hip arthroplasty (THA) were compared with patients aged ≥ 60 years (elderly) to evaluate the rate of revision arthroplasty, implant survival, the indications for revision, the complications, and the patient-reported outcomes.

Patients and Methods

We retrospectively reviewed all patients who underwent primary THA between January 2000 and May 2015 from our institutional database. A total of 145 very young and 1359 elderly patients were reviewed. The mean follow-up was 5.3 years (1 to 18). Logistic generalized estimating equations were used to compare characteristics and the revision rate. Survival was evaluated using Kaplan-Meier curves and hazard rates were created using Cox regression.

Results

The overall revision rate was 11% (16/145) in the very young and 3.83% (52/1359) in the elderly groups (odds ratio (OR) 2.58, 95% confidence interval (CI) 1.43 to 4.63). After adjusting for the American Society of Anesthesiologists (ASA) score, gender, and a history of previous surgery in a time-to-event model, the risk of revision remained greater in the very young (adjusted hazard ratio (HR) 2.48, 95% CI 1.34 to 4.58). Survival at ten years was 82% (95% CI, 71 to 89) in the very young and 96% (95% CI, 94 to 97) in the elderly group (p < 0.001). The very young had a higher rate of revision for complications related to metal-on-metal (MoM) bearing surfaces (p < 0.001). At last follow-up, the very young group had higher levels of physical function (p = 0.002), lower levels of mental health (p = 0.001), and similar levels of pain (p = 0.670) compared with their elderly counterparts.

Conclusion

The overall revision rate was greater in very young THA patients. This was largely explained by the use of MoM bearings. Young patients with non-MoM bearings had high survivorship with similar complication profiles to patients aged ≥ 60 years. Cite this article: Bone Joint J 2018;100-B:867-74.

Treated Versus Untreated Depression in Total Joint Arthroplasty Impacts Outcomes

BACKGROUND

To determine if there was a difference in the change in patient-reported physical function (PF) between nondepressed and medically treated depressed or untreated depressed total joint arthroplasty (TJA) patients.

METHODS

This is an Institutional Review Board exempt retrospective review of 280 TJA cases from March 2014 to May 2016. Patient-reported PF was measured as part of the routine care via the Patient Reported Outcomes Measurement Information System PF computerized adaptive test. Linear generalized estimating equation regression analyses were used.

RESULTS

Untreated depressed cases demonstrated much smaller gains in PF scores compared to nondepressed patients (P = .020). Additionally, although treated and untreated depressed patients had statistically similar preoperative and postoperative PF scores (P > .05), untreated depressed cases experienced a lower magnitude of change (P = .015).

CONCLUSION

Medically treated depressed patients may have similar PF gains as nondepressed patients. Larger prospective studies may help identify whether screening for untreated depression and subsequent treatment leads to improved outcomes.

Adding Value to Total Joint Arthroplasty Care in an Academic Environment: The Utah Experience

BACKGROUND

Adding value in a university-based academic health care system provides unique challenges when compared to other health care delivery models. Herein, we describe our experience in adding value to joint arthroplasty care at the University of Utah, where the concept of value-based health care reform has become an embraced and driving force.

METHODS

To improve the value, new resources were needed for care redesign, physician leadership, and engagement in alternative payment models. The changes that occurred at our institution are described.

RESULTS

Real-time data and knowledgeable personnel working behind the scenes, while physicians provide clinical care, help move clinical pathway redesigns. Engaged physicians are essential to the successful implementation of value creation and care pathway redesign that can lead to improvements in value. An investment of money and resources toward added infrastructure and personnel is often needed to realize large-scale improvements. Alignment of providers, payers, and hospital administration, including by means of gainsharing programs, can lead to improvements.

CONCLUSION

Although significant care pathway redesign efforts may realize substantial initial cost savings, savings may be asymptotic in nature, which calls into question the likely sustainability of programs that incentivize or penalize payments based on historical targets.

Evaluating instrument responsiveness in joint function: The HOOS JR, the KOOS JR, and the PROMIS PF CAT

12345Responsiveness is the ability to detect change over time and is an important aspect of measures used to detect treatment effects. The purpose of this study was to assess the responsiveness of the HOOS JR, the KOOS JR, and the PROMIS Physical Function (PF) computerized adaptive test (CAT) in a joint reconstruction practice. 983 patients were evaluated for joint conditions between 2014 and 2017 in an orthopaedic clinic and completed the three instruments at baseline and 3 and/or 6-month follow-up visits. Average age was 61.03 years (SD = 12.33, Range = 18-90 years) and the majority of the patients were White (n = 875, 89.0%). Three-month responsiveness was calculated two ways, as between 80 and 100 days and as 90 days and beyond. Six-month responsiveness was calculated as 170-190 days and as 180 days and beyond. All changes from baseline scores were significant at the 3-, >3-, and >6-month follow-up (p < 0.05). All three measures showed large effect sizes, ranging from 0.80-1.20 at each time-point. The standardized response mean was large for each measure and at each time-point (Range = 1.06-1.53). This study demonstrated the responsiveness of the HOOS JR, KOOS JR, and the PROMIS PF in adult reconstruction patients. The PROMIS PF was consistently the most responsive instrument in this analysis.

CLINICAL SIGNIFICANCE

The HOOS JR, KOOS JR, and PROMIS PF are useful clinical instruments for assessing treatment change and may be selected as relevant to the specific needs and conditions of the adult joint reconstruction patient population. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1178-1184, 2018.

Improving Value in Total Joint Arthroplasty: A Comprehensive Patient Education and Management Program Decreases Discharge to Post-Acute Care Facilities and Post-Operative Complications

BACKGROUND

A step-by-step approach to creating a comprehensive patient education, expectation, and management program is described with the aim of reducing discharges to post-acute care centers (PACs) following total joint arthroplasty (TJA). We hypothesized that by lowering discharges to PACs, readmissions and reoperations would also decrease.

METHODS

Following the implementation of a multi-faceted patient education and management program, we retrospectively reviewed 927 TJAs who underwent surgery 12 months before (n = 465) and after (n = 462) the program was implemented. To assess the exposure of the pathway on discharge disposition as well as institutional 30-day and 90-day readmissions and reoperations, a modified Poisson regression was used.

RESULTS

There was a 20% absolute reduction in discharges to PACs (<0.001). The frequency of 30-day readmissions was greater in patients who underwent TJA before implementation (incidence rate ratio [IRR] 1.93, 95% confidence interval [CI] 1.01-3.69). The risk for 90-day readmissions (IRR 1.70, 95% CI 1.20-2.40) and reoperations (IRR 1.67, 95% CI 1.12-2.53) was greater prior to implementation. Discharge to PACs was associated with 2.4 and 3.10 times greater risk for 30-day readmissions (95% CI 1.28-4.56) and 30-day reoperations (95% CI 1.40-7.0), respectively. Patients discharged to PACs were also at greater risk for both 90-day readmissions (IRR 1.59, 95% CI 1.08-2.32) and 90-day reoperations (IRR 1.75, 95% CI 1.12-2.73).

CONCLUSION

Our program led to a reduction in the number of patients being discharged to PACs following TJA, while also demonstrating a reduction in readmission and reoperations. Additionally, discharge to these facilities was an independent risk factor for these complications.

A Chlorhexidine Solution Reduces Aerobic Organism Growth in Operative Splash Basins in a Randomized Controlled Trial

BACKGROUND

Despite recommendations against the use of splash basins, due to the potential of bacterial contamination, our observation has been that they continue to be used in operating theaters. In hopes of decontaminating the splash basin, we sought to determine if the addition of chlorhexidine gluconate (CHG) would eliminate aerobic bacterial growth within the splash basin.

METHODS

After Institutional Review Board approval, we began enrollment in a randomized controlled trial comparing 2 splash basin solutions. Splash basins (n = 111) were randomized to either the standard of care (control) solution of sterile water or the experimental solution containing 0.05% CHG. One 20 mL aliquot was taken from the basin at the end of the surgical case and delivered to an independent laboratory. Samples were plated on tryptic soy agar (medium) and incubated at 30°C-35°C to encourage growth. After 48-72 hours, the agar plates were examined for growth and a standard plate count of aerobic cultures was performed.

RESULTS

The sterile water group was found to have bacterial growth in 9% of samples compared to no growth in the CHG group (P = .045). The organisms included Micrococcus luteus, Staphylococcus hominis, Gram-variable coccobacilli, and unidentifiable Gram-positive rods.

CONCLUSION

Given the safety and efficacy of a concentration of 0.05% CHG in reducing the bacterial contamination in the operative splash basin, it would seem that if the practice of using a splash basin in the operating theater is to be continued, the addition of an antiseptic solution such as that studied here should be considered.

Challenges in Total Hip Arthroplasty in the Setting of Developmental Dysplasia of the Hip

BACKGROUND

Developmental dysplasia of the hip (DDH) is a recognized cause of secondary arthritis, which may eventually lead to total hip arthroplasty (THA). An understanding of the common acetabular and femoral morphologic abnormalities will aid the surgeon in preparing for the complexity of the surgical case.

METHODS

We present the challenges associated with acetabular and femoral morphologies that may be present in the dysplastic hip and discuss surgical options to consider when performing THA. In addition, common complications associated with this population are reviewed.

RESULTS

The complexity of THA in the DDH patient is due to a broad range of pathomorphologic changes of the acetabulum and femur, as well as the diverse and often younger age of these patients. As such, THA in the DDH patient may offer a typical primary hip arthroplasty or be a highly complex reconstruction. It is important to be familiar with all the subtleties associated with DDH in the THA population. The surgeon must be prepared for bone deficiency when reconstructing the acetabulum and should place the component low and medial (at the anatomic hip center), and avoid oversizing the acetabular component. Femoral dysplasia is also complex and variable, and the surgeon must be prepared for different stem choices that allow for decoupling of the metaphyseal stem fit from the implanted stem version. In Crowe III and IV dysplasia, femoral derotation/shortening osteotomy may be required. Many complications associated with THA in the DDH patient may be mitigated with careful planning and surgical technique.

CONCLUSION

Performed correctly, THA can yield excellent results in this complex patient population.

Familial Clustering Identified in Periprosthetic Joint Infection Following Primary Total Joint Arthroplasty: A Population-Based Cohort Study

BACKGROUND

It is estimated that the cost to treat periprosthetic joint infection in the United States will approach $1.62 billion by 2020. Thus, the need to better understand the pathogenesis of periprosthetic joint infection is evident. We performed a population-based, retrospective cohort study to determine if familial clustering of periprosthetic joint infection was observed.

METHODS

Analyses were conducted using software developed at the Utah Population Database (UPDB) in conjunction with the software package R. The cohort was obtained by querying the UPDB for all patients undergoing total joint arthroplasty and for those patients who had subsequent periprosthetic joint infection. The magnitude of familial risk was estimated by hazard ratios (HRs) from Cox regression models to assess the relative risk of periprosthetic joint infection in relatives and spouses. Using percentiles for age strata, we adjusted for sex, body mass index (BMI) of ≥30 kg/m, and a history of smoking, diabetes, and/or end-stage renal disease. Additionally, we identified families with excess clustering of periprosthetic joint infection above that expected in the population using the familial standardized incidence ratio.

RESULTS

A total of 66,985 patients underwent total joint arthroplasty and 1,530 patients (2.3%) had a periprosthetic joint infection. The risk of periprosthetic joint infection following total joint arthroplasty was elevated in first-degree relatives (HR, 2.16 [95% confidence interval (CI), 1.29 to 3.59]) and combined first and second-degree relatives (HR, 1.79 [95% CI, 1.22 to 2.62]). Further, 116 high-risk pedigrees with a familial standardized incidence ratio of >2 and a p value of <0.05 were identified and 9 were selected for genotyping studies based on the observed periprosthetic joint infection/total joint arthroplasty ratio and visual inspection of the pedigrees for lack of excessive comorbidities.

CONCLUSIONS

Although preliminary, these data may help to guide further genetic research associated with periprosthetic joint infections. An understanding of familial risks could lead to new discoveries in creating patient-centered pathways for infection prevention in patients at risk.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Acetabular Wall Indices Help to Distinguish Acetabular Coverage in Asymptomatic Adults With Varying Morphologies

BACKGROUND

The anterior wall index (AWI) and posterior wall index (PWI) have been proposed to quantify anterior and posterior acetabular coverage using AP pelvic radiographs. However, these indices have only been reported in symptomatic patients with apparent pathomorphologies (dysplasia, overcoverage, and retroversion) undergoing osteochondroplasty or reorientation osteotomy.

QUESTIONS

(1) What are the ranges for AWI and PWI from measurements obtained on AP pelvic radiographs of asymptomatic senior athletes with well-functioning hips? (2) Is there a difference between the AWI and PWI in asymptomatic athletes with acetabular morphology consistent with acetabular dysplasia, overcoverage, and retroversion when compared with asymptomatic hips that do not meet the radiographic definitions for those morphologies (controls)?

METHODS

Five hundred five athletes (998 asymptomatic native hips) were independently evaluated by two readers on AP pelvic radiographs for AWI and the PWI after excluding hips with prior surgery, inadequate radiographs, or poor function (modified Harris hip score < 80). Hips with a lateral center-edge angle (LCEA) ≥ 20° and ≤ 38° and without acetabular retroversion, based on a positive crossover sign, were used as controls. Hips were categorized as developmental dysplasia of the hip (DDH; undercoverage) if the LCEA was < 20°. Finally, overcoverage was defined as an LCEA > 38°. The mean age of the athletes was 67 years (range, 50-91 years) and 55% were men. Linear generalized estimating equation regression was used to compare each individual diagnosis (DDH, retroversion, overcoverage) with the controls for both AWI and PWI adjusting for age and sex.

RESULTS

The mean AWI in the study population was 0.36 (range, -0.02 to 0.91). The mean PWI was 1.13 (range, 0.12-1.74). The mean AWI and PWI in controls (n = 740) was 0.35 (range, -0.02 to 0.91) and 1.13 (range, 0.64-1.70), respectively. There were 25 (3%) with DDH in whom the mean AWI was 0.26 (range, 0.05-0.5) and the mean PWI was 1.03 (range, 0.71-1.3). There were 112 (11%) retroverted hips in whom the mean AWI was 0.42 (range, 0.1-0.89) and PWI was 1.02 (range, 0.61-1.5). There were 121 (12%) overcovered hips in whom the mean AWI was 0.43 (range, -0.18 to 0.85) and PWI was 1.22 (0.12-1.74). The AWI in the control hips was no different than that of DDH hips (β -0.06; 95% confidence interval [CI], -0.12 to 0.002; p = 0.059) but was found to be lower than retroverted hips (β 0.08; 95% CI, 0.04-0.11; p < 0.001) and overcovered hips (β 0.05; 95% CI, 0.03-0.08; p < 0.001). The PWI in control hips was greater than that of DDH hips (β -0.08; 95% CI, -0.14 to -0.02; p = 0.013) and retroverted hips (β -0.07; 95% CI, -0.11 to -0.04; p < 0.001) but was less than overcovered hips (β 0.07; 95% CI, 0.04-0.10; p < 0.001).

CONCLUSIONS

The measurements of AWI and PWI in well-functioning, asymptomatic hips may be useful in assessing anterior and posterior acetabular coverage because it was able to distinguish between different types of known pathologic morphology. Despite evidence of these morphologic variances, these senior athletes continued to function at a high level. Thus, the identification of morphologic variance was not consistent with signs of pathology, which further supports that early screening of morphology may not predict the development of symptomatic pathology. Future work should focus on comparing these indices for morphologic variance in both symptomatic and asymptomatic hips to determine whether these measurements can be used in identifying problematic hips and as reference ranges for surgical correction.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Operative Fluoroscopic Correction Is Reliable and Correlates With Postoperative Radiographic Correction in Periacetabular Osteotomy

BACKGROUND

Intraoperative fluoroscopy is commonly used to both guide the osteotomy and judge correction of the acetabular fragment in periacetabular osteotomy (PAO). Prior studies that have compared intraoperative fluoroscopic correction with postoperative radiographic correction were small studies that did not report intra- or interreader reliability.

QUESTIONS/PURPOSES

(1) What is the correlation between intraoperative fluoroscopic correction in PAO compared with the correction seen on postoperative radiographs? (2) What is the reliability of radiographic measures of correction in PAO?

METHODS

We performed a retrospective study of 121 patients (141 hips) who underwent PAO for symptomatic hip dysplasia at a tertiary referral center. Patients were included in the study if they had preoperative radiographs, intraoperative fluoroscopy, and minimum 6-week postoperative radiographs. Of the 272 PAO procedures performed in this time period, 61 patients who underwent PAO for retroversion and five patients with a history of Perthes disease were excluded as a result of the inability for these radiographic measures to judge fragment correction in PAOs for retroversion and the difficulty in measurement in post-Perthes deformity. Of the 206 PAOs performed for symptomatic acetabular dysplasia, 65 (32%) could not be analyzed because they lacked appropriate preoperative films, leaving 141 PAOs in 121 patients for analysis. The patients lacking appropriate preoperative films had them performed at an outside facility or had plain films that have since been destroyed. The lateral center-edge angle (LCEA) and acetabular index (AI) on the fluoroscopic views and postoperative radiographs were measured by two authors. The concordance between the amount of correction on intraoperative fluoroscopy and minimum 6-week postoperative measurements was analyzed using the concordance correlation coefficient (r_c) and a Bland-Altman analysis. Intra- and interrater reliability was calculated between measurements.

RESULTS

The amount of intraoperative correction of LCEA as measured on fluoroscopic images demonstrated substantial agreement with postoperative radiographs (r_c = 0.79; 95% confidence interval [CI], 0.73-0.85; p < 0.001) as did the AI (r_c = 0.77; 95% CI, 0.70-0.84; p < 0.001). The mean difference between intraoperative correction was only -0.38° (SD 3.6°) for LCEA and -0.84° (SD 3.4°) for AI. Interrater reliability for both LCEA and AI also demonstrated substantial agreement (all, r_c = 0.70-0.90) for preoperative, operative, and postoperative imaging. Furthermore, intrarater reliability for both LCEA and AI demonstrated almost perfect agreement for all measures (all, r_c > 0.81).

CONCLUSIONS

Intraoperative fluoroscopy is an accurate and reliable measure of correction of lateral coverage of the acetabular fragment during PAO. Further studies on measures of anterior coverage and acetabular version are needed to validate intraoperative fluoroscopic correction in these planes.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Convergent Validity of the Patient-Reported Outcomes Measurement Information System's Physical Function Computerized Adaptive Test for the Knee and Shoulder Injury Sports Medicine Patient Population

PURPOSE

To evaluate the convergent validity, precision, and completion times for the Physical Function Computerized Adaptive Test (PF-CAT) in a sports medicine patient population relative to standard measures of knee and shoulder function.

METHODS

We reviewed all patient visits from April through September 2014 with either knee or shoulder complaints from a university-based sports medicine clinic, during which PF-CAT, Single Assessment Numerical Evaluation (SANE), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) outcome scores for shoulder patients and PF-CAT, SANE, and International Knee Documentation Committee (IKDC) scores for knee patients were obtained, with an initial visit or one follow-up visit included in the study. Spearman correlation was used to evaluate pairwise agreement among scores. The McNemar χ² test was used to evaluate a difference in the number of times floor and ceiling values occurred. Wilcoxon signed rank tests were used to compare differences in completion times.

RESULTS

In total, 415 shoulder and 450 knee clinical evaluations qualified for inclusion in the study. A high correlation was found between IKDC and PF-CAT scores (r = 0.75, P < .0001), and a moderately high correlation was found between PF-CAT and both SST (r = 0.68, P < .0001) and ASES (r = 0.63, P < .0001) scores. Maximum differences in the sum of floor-ceiling values versus the PF-CAT were 15% for the SST (P < .0001), 2.5% for the ASES (ceiling only, P = .0133), and 5.8% for the shoulder SANE (floor P = .0012, ceiling P = .0269). The PF-CAT had values of 0.4% for the shoulder and 0.6% for the knee. Zero percent of IKDC scores but 6.9% of knee SANE scores hit floor or ceiling values (floor P = .0019, ceiling P = .0007). The PF-CAT median completion time was lower at 55 seconds versus 268 seconds for the IKDC assessment (P < .0001), whereas shoulder patients' times were 61, 139, and 116 seconds for the PF-CAT, SST, and ASES evaluation, respectively (P < .0001).

CONCLUSIONS

The PF-CAT showed a high correlation with IKDC scores and a moderately high correlation with ASES and SST outcomes. The PF-CAT takes significantly less time to complete and exhibits improved or similar floor and ceiling effects in comparison to IKDC, SST, and ASES scores. The PF-CAT can be used in evaluating sports medicine knee and shoulder patients.

LEVEL OF EVIDENCE

Level III, cross-sectional study.

Higher Frequency of Reoperation With a New Bicruciate-retaining Total Knee Arthroplasty

BACKGROUND

With as many as 25% of patients reporting residual knee symptoms after primary total knee arthroplasty (TKA), alternative implant designs and surgical techniques have been proposed to further reduce these symptoms. There is growing evidence that retention of the anterior cruciate ligament (ACL) results in more natural knee kinematics; thus, implants with more normal joint mechanics could provide improved physical function postoperatively and reduce the amount of residual symptoms. Advancements in the bicruciate-retaining (BCR) TKA implant design have been made, and based on these, we wished to compare the BCR with a more traditional cruciate-retaining (CR) implant.

QUESTIONS/PURPOSES

(1) Was there a difference in the risk of reoperation after primary TKA between BCR and CR implant designs? (2) Was there a difference in the radiographic findings of radiolucent lines (RLLs) between the implant designs? (3) Was there a difference in patient-reported and clinical outcomes between the two implant designs?

METHODS

Between January 2013 and May 2014, two surgeons performed 475 primary TKAs. During this time, 78 (16%) of these were performed with BCR implants and 294 (62%) with CR implants; the remainder were performed with anterior-stabilized or more constrained designs as a result of increased deformity and/or ligamentous deficiencies. During this period, the general indications for BCR TKA were arthritic knees with only slight to moderate deformity and sufficient ligamentous integrity of both the ACL and posterior cruciate ligament. The indications for CR TKA were similar other than these patients presented with a deficient ACL. A total of 66 (85%) of the BCR and 237 (81%) of the CR TKAs were available for followup at a minimum of 12 months or when reoperation occurred before 12 months (mean, 18 months; range, 2-32 months). With the numbers available, there were no differences between the groups in terms of age and sex, but the patients undergoing CR TKA had a greater mean body mass index (33 ± 7 versus 31 ± 5 kg/m², p = 0.032). The frequency of early reoperation was compared between the groups as were radiographic evidence of RLL, patient-reported outcomes, and knee range of motion (ROM).

RESULTS

Knees in the BCR group had a higher frequency of all-cause revision (5% [three of 66] versus 1.3% [three of 237]; hazard ratio (HR), 7.44; 95% confidence interval [CI], 1.24-44.80; p = 0.028). Knees in the BCR group had a higher frequency of irrigation and débridement with component retention (HR, 0.07; 95% CI, 0.02-0.28; p < 0.001). No differences were found between groups for subsequent manipulation (HR, 0.34; 95% CI, 0.08-1.42; p = 0.137). The proportion of RLLs was greater in the BCR group (HR, 2.93; 95% CI, 1.62-5.32; p < 0.001) compared with the CR group. There were no differences between the groups in terms of the Physical Function Computerized Adaptive Test scores, Global10 scores or knee ROM outcomes.

CONCLUSIONS

Preliminary short-term findings suggest the BCR implant has inferior survivorship and concerning radiographic findings when compared with a conventional CR implant with respect to complications after primary TKA. These findings raise concerns about the new BCR design; however, further randomized trials are necessary to determine superiority between alternative implant designs.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Femoral Morphology in Patients Undergoing Periacetabular Osteotomy for Classic or Borderline Acetabular Dysplasia: Are Cam Deformities Common?

BACKGROUND

The primary purpose of our study was to determine the prevalence of Cam deformity in patients with symptomatic acetabular dysplasia (SAD) who underwent periacetabular osteotomy (PAO).

METHODS

We retrospectively reviewed 164 SAD PAO patients from 2 institutions. Preoperative anteroposterior and frog-lateral radiographs were analyzed for lateral center edge angle (LCEA), retroversion, alpha angles, and anterior femoral head-neck offset. Hips were classified as dysplastic (LCEA <20°, group A, n = 142) and borderline dysplastic (LCEA 20°-25°, group B, n = 22). There were 128 females and 36 males with an average age of 29 years (range 13-56).

RESULTS

The overall prevalence of Cam deformity was 10% (17 of 164) in SAD patients. There was no difference in the prevalence of Cam deformity between the groups (P > .99).

CONCLUSION

Prevalence of Cam deformities in our series of SAD patients having undergone PAO is less than prior reports. Careful radiographic measurement should be performed to avoid overtreating these hips with unnecessary osteochondroplasty procedures.

Improving value in primary total joint arthroplasty care pathways: changes in inpatient physical therapy staffing

Background

An early physical therapy (PT) care pathway was implemented to provide same-day ambulation after total joint arthroplasty by changing PT staffing hours.

Methods

After receiving an exemption from our institutional review board, we performed a secondary data analysis on a cohort of patients that underwent primary TJA of the hip or knee 6 months before and 12 months after implementation of the change. Data on same-day ambulation rates, length of stay (LOS), and in-hospital costs were reviewed.

Results

Early evaluation and mobilization of patients by PT improved on postoperative day (POD) 0 from 64% to 85% after the change (P ≤ .001). The median LOS before the change was 3.27 days compared to 3.23 days after the change (P = .014). Patients with higher American Society of Anesthesiologists scores were less likely to ambulate on POD 0 (P = .038) and had longer hospital stays (P < .001). Early mobilization in the entire cohort was associated with a greater cost savings (P < .001).

Conclusions

A relatively simple change to staffing hours, using resources currently available to us, and little additional financial or institutional investment resulted in a significant improvement in the number of patients ambulating on POD 0, with a modest reduction in both LOS and inpatient costs.

Can Radiographs Predict the Use of Modular Stems in Developmental Dysplasia of the Hip?

BACKGROUND

Abnormal anatomy frequently results in the use of a modular stem in patients undergoing primary total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH). However, because these stems are not always available in the operating room, it would be helpful if standard radiographic views could be analyzed in such a way that patients whose femoral anatomy might call for stem modularity could be anticipated before surgery. To our knowledge, no such parameters have been defined.

QUESTIONS/PURPOSES

In the senior author's practice, we used femoral neck anteversion of more than 25° as a determinant for use of a modular stem. Given this criterion, we asked if we could reliably identify plain film radiographic parameters of the femur that predict the use of modular stems. We looked at the following: (1) the neck-shaft angle based on the anteroposterior (AP) radiograph (alpha); (2) the neck-shaft angle from the crosstable lateral radiograph (beta); and (3) the calculated femoral anteversion angle.

METHODS

We reviewed preoperative radiographs from 50 of 67 patients (79 hips) who had a primary diagnosis of DDH and underwent primary THA from January 1999 to February 2007 inclusive. Hips with prior femoral-sided surgery (n = 2) or without preoperative films (n = 19) were excluded. Furthermore, patients with bilateral hips had the second hip excluded (n = 8). Twenty-one of 50 received a modular femoral stem based on the criterion of intraoperative neck-shaft anteversion of greater than 25° as measured by the senior surgeon (CLP), whereas the remainder received tapered nonmodular stems. There were no differences in age, sex, height, or weight between the modular stem group and tapered stem group. Radiographs were evaluated to record the parameters listed.

RESULTS

Patients in whom modular femoral stems were used had a greater mean AP (alpha) neck-shaft angle compared with patients who received tapered nonmodular stem (152°; 95% confidence interval [CI], 146°-157° versus 137°; 95% CI, 134°-141°; p < 0.001) with an optimal cutoff point for determining the use of modular stems of ≥ 142° (receiver operating characteristic [ROC] area = 73%). Hips in which modular femoral stems were chosen had a smaller mean lateral (beta) neck-shaft angle (152°; 95% CI, 148°-157° versus 161°; 95% CI, 158°-164°; p = 0.003) with an optimal cutoff point of ≤ 153° (ROC area = 65%). Hips in which modular femoral stems were used had a higher femoral anteversion angle (mean 45°; 95% CI, 37°-54° versus 21°; interquartile range, 17°-25°; p < 0.001) with an optimal cutoff of ≥ 32° (ROC area = 80%).

CONCLUSIONS

Preoperative radiographs anticipated the use of modular stems during THA for DDH in a practice where modular stems were chosen on the basis of a neck-shaft angle of greater than 25° measured at surgery. We found that this could be predicted on preoperative radiographs based on smaller lateral neck-shaft angles, steeper AP radiographic neck-shaft angles, and increased femoral anteversion calculated using these angles. Prospective studies are needed to better determine if these cutoff values adequately predict the use of modular stems.

The 2015 Frank Stinchfield Award: Radiographic Abnormalities Common in Senior Athletes With Well-functioning Hips but Not Associated With Osteoarthritis

BACKGROUND

It is not known whether morphological abnormalities of the hip are compatible with lifelong hip function and avoidance of osteoarthritis (OA). Our purpose was to investigate the prevalence of radiographic findings consistent with femoroacetabular impingement (FAI) and dysplasia (DDH) in senior athletes with well-functioning hips.

QUESTIONS/PURPOSES

(1) What is the prevalence of FAI and DDH in senior athletes with well-functioning hips? (2) Are radiographic findings of FAI and DDH associated with OA? (3) Is a history of longer duration or more intense activity associated with hip pathomorphology? (4) Were the modified Harris hip scores and the Hip Outcome Scores lower (legacy scales) in patients with evidence of hip pathomorphology than those without?

METHODS

Five hundred forty-seven individuals (55% men, 45% women; 1081 hips, 534 bilateral and 13 unilateral), mean age 67 years (SD 8 years), gave consent and qualified for this institutional review board-approved cross-sectional study of senior athletes. Hips were independently evaluated for radiographic signs of FAI, DDH, and OA. Additionally, a lifetime activities questionnaire and outcome instruments were used to assess pain and function. Hips that had previously undergone arthroplasty or fracture surgery were excluded.

RESULTS

Eighty-three percent (898 of 1081) of hips had radiographic abnormalities consistent with FAI, of which 67% (599 of 898) were cam-type FAI. Ten percent (103 of 1081) of hips had radiographic evidence for dysplasia. Radiographic findings of FAI were not predictive of OA after controlling for age and sex (odds ratio [OR], 1.79; 95% confidence interval [CI], 0.48-6.62; p = 0.390). Similarly, radiographic findings of DDH were not predictive of OA (OR, 1.48; 95% CI, 0.31-7.21; p = 0.62). Our data suggest an increased risk of FAI-type morphologies in athletes who participated in competitive sporting events during early adult years (OR, 1.49; 95% CI, 1.04-2.11; p = 0.020). Additionally, participants who reported lifetime participation in competitive sports were at an increased risk of OA compared with those who did not (OR, 1.75; 95% CI, 1.14-2.69; p = 0.007). There were no differences in outcome scores between athletes with and without morphologic abnormalities.

CONCLUSIONS

Radiographic findings consistent with FAI in these senior athletes were common and were not associated with the presence of OA. These data suggest that the need to screen for asymptomatic young athletes for radiographic evidence of FAI and DDH may not be necessary.

LEVEL OF EVIDENCE

Level III, prognostic study.

A Heritable Predisposition to Osteoarthritis of the Hip

Using THA as a proxy for underlying osteoarthritis, we describe population-based familial clustering of osteoarthritis of the hip. The GIF test for excess relatedness on 1049 patients that underwent THA (and do not have a diagnostic code for other conditions leading to THA) showed excess relatedness (P<0.001). Even when close relationships were ignored (closer than third-degree relationships), excess relatedness was observed (P=0.020). Relative risk was elevated in first-degree (RR 2.59; 95% CI 1.84-3.53, P=2.0e(-7)), second-degree (RR 1.66; 95% CI 1.11-2.39; P=0.0075) and third-degree relatives (RR 1.46; 95% CI 1.17-1.81; P=5.7e(-4)). Excess relatedness of individuals who had undergone THA for osteoarthritis and elevated risks to both near and distant relatives were observed.

Is Hemoglobin A1c or Perioperative Hyperglycemia Predictive of Periprosthetic Joint Infection or Death Following Primary Total Joint Arthroplasty?

We sought to determine if HbA1c and perioperative hyperglycemia were positively associated with the incidence of PJI. We retrospectively reviewed the VA VINCI database on patients who underwent primary joint arthroplasty between 2001 and 2011 and had HbA1c and perioperative blood glucose levels. Of 13,272 patients, 38% (n=5035) had an elevated perioperative HbA1c ≥7%. While there was no increased risk of infection associated with elevated HbA1c (HR 0.86, P=0.23), mortality was increased (HR 1.3, P=0.01). Preoperative hyperglycemia was associated with an increased incidence of PJI (HR 1.44, P=0.008). While HbA1c did not perfectly correlate with the risk of PJI, perioperative hyperglycemia did, and may be a target for optimization to decrease the burden of PJI.

The prevalence of radiographic findings of structural hip deformities in female collegiate athletes

BACKGROUND

Structural deformities of the hip, including femoroacetabular impingement (FAI) and acetabular dysplasia, often limit athletic activity. Previous studies have reported an increased prevalence of radiographic cam FAI in male athletes, but data on the prevalence of structural hip deformities in female athletes are lacking.

PURPOSE

(1) To quantify the prevalence of radiographic FAI deformities and acetabular dysplasia in female collegiate athletes from 3 sports: volleyball, soccer, and track and field. (2) To identify possible relationships between radiographic measures of hip morphologic characteristics and physical examination findings.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Anteroposterior (AP) pelvis and frog-leg lateral radiographs were obtained from 63 female athletes participating in Division I collegiate volleyball, soccer, and track and field. Lateral center edge angle (LCEA) and acetabular index were measured on AP films. Alpha angle and head-neck offset were measured on frog-leg lateral films. Pain during the supine impingement examination and hip rotation at 90° of flexion were recorded. Random-effects linear regression was used for group comparisons and correlation analyses to account for the lack of independence of observations made on left and right hips.

RESULTS

Radiographic cam deformity (alpha angle >50° and/or head-neck offset <8 mm) was found in 48% (61/126) of hips. Radiographic pincer deformity (LCEA >40°) was noted in only 1% (1/126) of hips. No hips had radiographic mixed FAI (at least 1 of the 2 cam criteria and LCEA >40°). Twenty-one percent (26/126) of hips had an LCEA <20°, indicative of acetabular dysplasia, and an additional 46% (58/126) of hips had borderline dysplasia (LCEA ≥20° and ≤25°). Track and field athletes had significantly increased alpha angles (48.2° ± 7.1°) compared with the soccer players (40.0° ± 6.8°; P < .001) and volleyball players (39.1° ± 5.9°; P < .001). There was no significant difference in the LCEA (all P > .914) or the prevalence of dysplasia (LCEA <20°) between teams (all P > .551). There were no significant correlations between the radiographic measures and internal rotation (all P > .077). There were no significant differences (all P > .089) in radiographic measures between hips that were painful (n = 26) during the impingement examination and those that were not.

CONCLUSION

These female athletes had a lower prevalence of radiographic FAI deformities compared with previously reported values for male athletes and a higher prevalence of acetabular dysplasia than reported for women in previous studies.

Preservation of the rectus femoris origin during periacetabular osteotomy does not compromise acetabular reorientation

BACKGROUND

The early recovery period after periacetabular osteotomy (PAO) can be limited by pain and activity restrictions. Modifications of the Bernese PAO, including sparing the rectus tendon and discontinuing routine arthrotomy, may accelerate early postoperative recovery compared with the standard approach.

QUESTIONS/PURPOSES

Does a modified approach for PAO (1) lead to improved pain control immediately after surgery; (2) lead to improved ambulation during the hospital stay; (3) lead to shorter stays, less blood loss, and shorter surgical times; and (4) compromise acetabular correction?

METHODS

We retrospectively reviewed all 75 patients who underwent PAO for developmental dysplasia of the hip between August 2009 and May 2013. The control group included 44 consecutive patients who underwent a standard Bernese PAO with rectus takedown (RT). The study group consisted of 31 consecutive patients who underwent PAO using a modified rectus-sparing (RS) approach without routine arthrotomy. The groups were similar in age, body mass index, and American Society of Anesthesiologists score, but the RT group was comprised of a greater percentage of men than the RS group. Outcome variables were collected from patient charts and included inpatient pain, inpatient ambulation as well as length of stay, estimated blood loss, surgical time, and postoperative radiographic measurements. Cohen's f(2) was used to calculate the effect size in the regression analysis and effects were considered small for values<0.15, moderate for 0.15 to 0.34, and large for values>0.35.

RESULTS

Patients who underwent PAO with a RS approach had less overall pain (RT median 4 versus RS median 2); however, the difference may not have been perceptible to the typical patient (p=0.001, f2=0.059). Patients treated with the RS approach ambulated similar distances during the hospital stay with a median 11 feet (interquartile range [IQR], 0-72.5) for the RT group and a median 30 feet (IQR, 0-100) for the RS group (p=0.215, f2=0.095). Patients in the RT group had a median length of stay of 4 days (IQR, 4-5) compared with a median 3 days (IQR, 3-4) in the RS group (p<0.001). The median estimated blood loss was greater (p=0.010) in the RT group (median, 500 mL; IQR, 350-700) versus the RS group (median, 300; IQR, 250-500). The median surgical time was longer (p<0.001) in patients undergoing PAO with the RT approach (median, 159.5 minutes; IQR, 145.5-177) compared with the RS approach (median, 103 minutes; IQR, 75-114). Acetabular reorientation based on postoperative radiographs was not compromised by the modified approach.

CONCLUSIONS

The approach modification was straightforward to implement in all patients and did not compromise acetabular fragment mobilization or final positioning. Two of the three key variables that the approach might have influenced-pain and length of stay-were below the minimum clinically important difference and different by only a fraction of a day, respectively. The difference in ambulation was of only modest clinical importance. More definitive evidence for clinical superiority in terms of pain, ambulation, and return of muscle function will likely require more sophisticated instruments such as gait analysis, muscle strength testing, and longer-term outcome studies with sensitive instruments.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.