Quality of life and cost-effectiveness 1 year after total hip arthroplasty

The Subjective Hip Value is a Valid, Reliable, and Responsive Instrument for Assessing Hip Function in Primary Total Hip Arthroplasty

BACKGROUND

Patient-reported outcome measures are essential tools in clinical decision-making and research. Multi-item scores like the modified Harris Hip Score (mHHS) are time-consuming to collect and evaluate. The subjective hip value (SHV), as a single-item value, assesses hip function with one question: "What is the overall percent value of your hip if a completely normal hip represents 100%?". The aims of our study were to assess the psychometric properties, and thus validity, reliability, and responsiveness; and to define the minimal clinically important difference (MCID) of the SHV in patients undergoing total hip arthroplasty.

METHODS

A total of 137 consecutive patients who underwent primary total hip arthroplasty between June 2020 and August 2021 were prospectively enrolled. A SHV and mHHS were collected preoperatively and at follow-ups (6 weeks, 3 months, 6 months, and 1 year). Validity, reliability, responsiveness, MCID, and floor/ceiling effects were evaluated.

RESULTS

There was a significant correlation between SHV and mHHS (P = .001) preoperatively (rs = 0.532), 6 weeks (rs = 0.649), 3 months (rs = 0.765), 6 months (rs = 0.854), and after 1 year (rs = 0.879). Test-retest reliability (rs = 0.74; P = .001) and responsiveness (rs = 0.24; P = .007) showed significant correlations. The MCID for SHV was 10.06%. Floor- and ceiling-effects were comparable to the mHHS.

CONCLUSIONS

The SHV is a valid, reliable, and responsive single-item score for the assessment of hip joint function in arthroplasty patients. It can detect clinically relevant changes in joint function and is easy to collect and interpret, which justifies its implementation in clinical practice.

Impact of the hip-spine relationship and patient-perceived leg length discrepancy after total hip arthroplasty: A retrospective study

PURPOSE

Patient-perceived leg length discrepancy (PLLD) is one of the major postoperative complications of total hip arthroplasty (THA). This study aimed to identify factors that cause PLLD following THA.

MATERIALS AND METHODS

This retrospective study included a series of consecutive patients who underwent unilateral THA between 2015 and 2020. Ninety-five patients who underwent unilateral THA with postoperative radiographic leg length discrepancy (RLLD) ≤1 cm were classified into two groups according to the direction of preoperative pelvic obliquity (PO). Standing radiographs of the hip joint and whole spine were obtained before and one year after THA. The clinical outcomes and the presence or absence of PLLD was confirmed one year after THA.

RESULTS

Sixty-nine patients were classified as having type 1 PO (rising toward the unaffected side) and 26 were classified as having type 2 PO (rising toward the affected side). Eight patients with type 1 PO and seven with type 2 PO had PLLD postoperatively. In the type 1 group, patients with PLLD had larger preoperative and postoperative PO values and larger preoperative and postoperative RLLD than those without PLLD (p = 0.01, p < 0.001, p = 0.01, and p = 0.007, respectively). In the type 2 group, patients with PLLD had larger preoperative RLLD, larger amount of leg correction, and a larger preoperative L1-L5 angle than those without PLLD (p = 0.03, p = 0.03, and p = 0.03, respectively). In type 1, postoperative PO was significantly associated with postoperative PLLD (p = 0.005), but spinal alignment was not an indicator of postoperative PLLD. The area under the curve (AUC) for postoperative PO was 0.883 (good accuracy) with a cut-off value was 1.90° CONCLUSION: Rigidity of the lumbar spine might lead to postoperative PO as a compensatory movement, resulting in PLLD after THA in type 1. Further research on the relationship between flexibility of the lumbar spine and PLLD is needed.

A new designed full process coverage robot-assisted total hip arthroplasty: a multicentre randomized clinical trial

OBJECTIVE

To compare the effect of a new complete robot-assisted total hip arthroplasty (RA-THA) with that of the manual total hip arthroplasty (MTHA) and to verify the accuracy and safety of the former.

METHODS

Overall, 148 patients were enroled from 3 March 2021 to 28 December 2021 in this study and classified into RA-THA ( n =74 patients) and MTHA ( n =74 patients) groups. The sex, age, operative side, BMI, diagnosis, other basic information, operative time, acetabular prosthesis anteversion and inclination, femoral prosthesis anteversion and angulation, femoral prosthesis filling rate, leg length discrepancy (LLD), Harris hip score, and visual analogue scale (VAS) score of the two groups were compared.

RESULTS

No significant differences were observed in the two groups regarding sex, age, operative side, BMI, diagnosis, Harris hip score, VAS score, acetabular inclination, acetabular prosthesis anteversion, femoral prosthesis anteversion, combined anteversion, and femoral prosthesis filling rate ( P >0.05). The operative time was significantly longer in the RA-THA group than in the MTHA group (106.71±25.22 min vs. 79.42±16.16 min; t=7.30, P <0.05). The femoral angulation (1.78°±0.64°) and LLD (2.87±1.55 mm) in the RA-THA group were significantly lesser than those in the MTHA group (2.22°±1.11° and 5.81±6.27 mm, respectively; t=-2.95 and t=-3.88, P <0.05).

CONCLUSION

The complete RA-THA has some advantages over the traditional procedure in restoring the lower limb length and controlling the femoral prosthesis angulation. Thus, this study verifies the accuracy and safety of the robot-assisted system.

Pain and rehabilitation after total hip arthroplasty are approach dependent: results 6 weeks and 2 years after surgery in a multisurgeon, single-center, and prospective cohort study

PURPOSE

The aim of this study was the evaluation of pain, function, and overall satisfaction after total hip arthroplasty (THA) using three different standard surgical approaches (DAA (direct anterior approach), lateral, and posterior approach) 2 years postoperatively. Additionally, we compared the results with recently published results of the same study population 6 weeks postoperatively.

METHODS

In a multisurgeon, prospective, single-center cohort study, a total of initial 188 patients who underwent total hip arthroplasty (THA) between February 2019 and April 2019 were analyzed on pain, function, and satisfaction within the first days, 6 weeks, and 2 years postoperatively according to three different approaches (DAA, lateral, and posterior approach). Our research group recently published results directly and 6 weeks postoperatively. We evaluated the same study collectively 2 years postoperatively and compared the results with the data 6 weeks postoperatively. One hundred twenty-five patients could be included. Outcome parameters for the present study were the pain level according to the visual analogue scale (VAS), the modified Harris hip score (mHHS), and an overall satisfaction scale 2 years postoperatively.

RESULTS

Mean overall satisfaction 2 years postoperatively was 9.7 ± 1 (3-10). Satisfaction was significantly better for the DAA than for the lateral approach (p = 0.005). There were no significant differences between the lateral and posterior approaches (p = 0.06) and between the DAA and the posterior approaches (p = 0.11). In total, the mean pain level was 0.4 ± 0.9 (0-5) at 6 weeks and 0.5 ± 1.1 (0-7) at 2 years postoperatively (p = 0.3). Regarding the different approach groups, pain levels 6 weeks and 2 years postoperatively were significantly lower for the DAA than for the lateral approach (p = 0.02). There were no significant differences between DAA and posterior approach (p = 0.05) and the lateral and posterior approach (p = 0.26). The mean mHHS significantly increased from 84.7 + 14.5 (37.4-100) 6 weeks to 95 + 12.5 (23.1-100.1) 2 years postoperatively (p < 0.0001). Regarding the different approaches, mHHS was significantly higher for the DAA than for the lateral approach (p = 0.03). Differences between the DAA and the posterior approach (p = 0.11) and between the lateral and posterior approaches (p = 0.24) were insignificant.

CONCLUSION

At 2 years postoperative, DAA showed significantly better overall satisfaction, pain level, and mHHS than the lateral approach. The differences between DAA and the posterior approach and lateral and posterior approaches were insignificant. Whether the superior results of the DAA to the lateral approach persist over a longer period must be clarified by further studies.

STUDY DESIGN

Prospective cohort study, level of evidence 2.

Pain and rehabilitation after total hip arthroplasty are approach dependent: a multisurgeon, single-center, prospective cohort study

PURPOSE

The aim of this study was to assess perioperative pain and mobilization after total hip arthroplasty (THA) using three different surgical approaches.

METHODS

This was a multisurgeon, prospective, single-center cohort study. A total of 188 patients who underwent hip arthroplasty (THA) between February 2019 and April 2019 were analyzed according to the surgical approach used (direct anterior, lateral, and posterior approach). Outcome parameters were the daily walking distance during the inpatient stay, the pain level according to the visual analog scale (VAS) at rest and motion during the inpatient stay and at 6-week follow-up and the modified Harris Hips Score (mHHS) preoperatively and at 6 weeks.

RESULTS

The walking distance within the groups increased significantly during the inpatient stay (p < 0.001). The DAA and posterior approach patients had a significantly longer walking distance than the lateral approach patients on the third postoperative day (DAA vs. lateral, p = 0.02; posterior vs. lateral 3, p = 0.03). DAA and posterior approach patients reported significantly less pain during motion on the third postoperative day and at 6-week follow-up than the lateral approach patients (3 postoperative day: DAA vs. lateral, p = 0.011; posterior vs. lateral, p = 0.04; 6 weeks control: DAA vs. lateral, p = 0.001; Posterior vs. lateral 3, p = 0.005). The mHHS demonstrated significant improvement within each group. However, lateral approach patients reported significantly less improvement than the DAA and posterior approach patients (DAA vs. lateral, p = 0.007; posterior vs. lateral, p = 0.021).

CONCLUSION

This study analyzed perioperative pain progression and short-term rehabilitation after THA according to the different surgical approaches. Direct anterior and posterior approaches have shown comparable improvements in pain, walking distance, and mHHS. Whether this effect persists over a longer period of time must be clarified in future studies.

STUDY DESIGN

Prospective cohort study, level of evidence, 2.

Is the Direct Anterior Approach to THA Cost-effective? A Markov Analysis

BACKGROUND

The use of the direct anterior approach, a muscle-sparing technique for THA, has increased over the years; however, this approach is associated with longer procedure times and a more expensive direct cost. Furthermore, studies have shown a higher revision rate in the early stages of the learning curve. Whether the clinical advantages of the direct anterior compared with the posterior approach-such as less soft tissue damage, decreased short-term postoperative pain, a lower dislocation rate, decreased length of stay in the hospital, and higher likelihood of being discharged home-outweigh the higher cost is still debatable. Determining the cost-effectiveness of the approach may inform its utility and justify its use at various stages of the learning curve.

QUESTIONS/PURPOSES

We used a Markov modeling approach to ask: (1) Is the direct anterior approach more likely to be a cost-effective approach than the posterior approach over the long-term for more experienced or higher volume hip surgeons? (2) How many procedures does a surgeon need to perform for the direct anterior approach to be a cost-effective choice?

METHODS

A Markov model was created with three health states (well-functioning THA, revision THA, and death) to compare the cost-effectiveness of the direct anterior approach with that of the posterior approach in five scenarios: surgeons who performed one to 15, 16 to 30, 31 to 50, 51 to 100, and more than 100 direct anterior THAs during a 6-year span. Procedure costs (not charges), dislocation costs, and fracture costs were derived from published reports, and model was run using two different cost differentials between the direct anterior and posterior approaches (USD 219 and USD 1800, respectively). The lower cost was calculated as the total cost differential minus pharmaceutical and implant costs to account for differences in implant use and physician preference regarding postoperative pain management. The USD 1800 cost differential incorporated pharmaceutical and implant costs. Probabilities were derived from systematic review of the evidence as well as from the Australian Orthopaedic Association National Joint Replacement Registry. Utilities were estimated from best available literature and disutilities associated with dislocation and fracture were incorporated into the model. Quality of life was expressed in quality-adjusted life years (QALYs), which are calculated by multiplying the utility of a health state (ranging from 0 to 1) by the duration of time in that health state. The primary outcome measure was the incremental cost-effectiveness ratio, or the change in costs divided by the change in QALYs when the direct anterior approach was used for THA. USD 100,000 per quality-adjusted life years was used as a threshold for willingness to pay. One-way and probabilistic sensitivity analyses were performed for the scenario in which the direct anterior approach is cost-effective to further account for uncertainty in model inputs.

RESULTS

At a cost differential of USD 219 (95% CI 175 to 263), the direct anterior approach was associated with lower cost and higher effectiveness compared with the posterior approach for surgeons with an experience level of more than 100 operations during a 6-year span. At a cost differential of USD 1800 (95% CI 1440 to 2160), the direct anterior approach remained a cost-effective strategy for surgeons who performed more than 100 operations. At both cost differentials, the direct anterior approach was not cost-effective for surgeons who performed fewer than 100 operations. One-way sensitivity analyses revealed the model to be the most sensitive to fluctuations in the utility of revision THA, probability of revision after the posterior approach THA, probability of dislocation after the posterior approach THA, fluctuations in the probability of dislocation after direct anterior THA, cost of direct anterior THA, and probability of intraoperative fracture with the direct anterior approach. At the cost differential of USD 219 and for surgeons with a surgical experience level of more than 100 direct anterior operations, the direct anterior approach was still the cost-effective strategy for the entire range of values.

CONCLUSION

For high-volume hip surgeons, defined here as surgeons who perform more than 100 procedures during a 6-year span, the direct anterior approach may be a cost-effective strategy within the limitations imposed by our analysis. For lower volume hip surgeons, performing a more familiar approach appears to be more cost-effective.

Outcomes of Revision Hip Arthroplasty Using the Supine Anterior-Based Muscle Sparing Approach

Background

In the United States, the number of revision total hip arthroplasty (THA) cases is projected to grow from 50,000 in 2014 to 85,000 by 2030. The anterior-based muscle sparing approach (ABMS) has been described as a viable approach for primary THA, but little has been written in the revision setting. This study compares the supine ABMS approach to alternative approaches in revision THA.

Material and methods

A retrospective review was performed on 149 revision THAs from 2016 to 2019. The ABMS, modified Müller Hardinge (MMH), and posterolateral (PL) approaches were studied. Age, reason for arthroplasty, length of operation, length of stay, blood loss, and complications were extracted. Clinical outcomes were measured by the Hip Disability and Osteoarthritis Outcome Score, Modified Harris Hip Score, University of California Los Angeles activity score, and Veterans RAND 12 Mental/Physical scores.

Results

Approaches included 52 ABMS (33.8%), 58 MHH (37.7%), and 39 PL (25.3%). Complexity of cases and patient demographics were equivalent for each cohort. Extensile approaches were used in 12 of the 52 ABMS, 26 of the 58 MMH, and 13 of the 39 PL revisions, including acetabular cages, open reduction internal fixation for periprosthetic fracture, extended trochanteric osteotomy, hardware removal, and/or pelvic discontinuity. There were no differences for blood loss, length of stay, complications, and outcome scores between approaches.

Conclusion

We found no difference in complications or clinical outcome scores between the ABMS, MMH, and PL approaches for revision THA. The supine ABMS approach provides adequate extensile exposure of the femur and acetabulum for complex revisions and is a reliable approach for revision THA.

Adult Spinal Deformity Surgery Is Associated with Increased Productivity and Decreased Absenteeism From Work and School

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

We hypothesized that adult spinal deformity (ASD) surgery would be associated with improved work- and school-related productivity, as well as decreased rates of absenteeism.

SUMMARY OF BACKGROUND DATA

ASD patients experience markedly decreased health-related quality of life along many dimensions.

METHODS

Only patients eligible for 2-year follow-up were included, and those with a history of previous spinal fusion were excluded. The primary outcome measures in this study were Scoliosis Research Society-22r score (SRS-22r) questions 9 and 17. A repeated measures mixed linear regression was used to analyze responses over time among patients managed operatively (OP) versus nonoperatively (NON-OP).

RESULTS

In total, 1188 patients were analyzed. 66.6% were managed operatively. At baseline, the mean percentage of activity at work/school was 56.4% (standard deviation [SD] 35.4%), and the mean days off from work/school over the past 90 days was 1.6 (SD 1.8). Patients undergoing ASD surgery exhibited an 18.1% absolute increase in work/school productivity at 2-year follow-up versus baseline (P < 0.0001), while no significant change was observed for the nonoperative cohort (P > 0.5). Similarly, the OP cohort experienced 1.1 fewer absent days over the past 90 days at 2 years versus baseline (P < 0.0001), while the NON-OP cohort showed no such difference (P > 0.3). These differences were largely preserved after stratifying by baseline employment status, age group, sagittal vertical axis (SVA), pelvic incidence minus lumbar lordosis (PI-LL), and deformity curve type.

CONCLUSION

ASD patients managed operatively exhibited an average increase in work/school productivity of 18.1% and decreased absenteeism of 1.1 per 90 days at 2-year follow-up, while patients managed nonoperatively did not exhibit change from baseline. Given the age distribution of patients in this study, these findings should be interpreted as pertaining primarily to obligations at work or within the home. Further study of the direct and indirect economic benefits of ASD surgery to patients is warranted.Level of Evidence: 3.

Outcomes of the Supine Anterior-based Muscle-sparing Approach for Primary and Revision Hip Arthroplasty

INTRODUCTION

Risks and outcomes of total hip arthroplasty (THA) are believed to vary relative to the surgical approach. This study compares the supine anterior-based muscle-sparing (ABMS) approach with its modern-day counterparts.

METHODS

A retrospective review was done on 550 patients undergoing primary or revision THA from 2016 to 2018. Surgical modalities included direct anterior (DAA), ABMS, posterolateral, and Müller modified Hardinge approaches. Surgical data were collected, and clinical outcomes were measured by the Hip Disability and Osteoarthritis Outcome Score, Modified Harris Hip Score, UCLA, and VR-12 Mental/Physical scores preoperatively and compared clinical outcomes among approaches.

RESULTS

A total of 550 patients were included (447 primaries, 103 revisions). The average age was 64 years (231 men, 319 women). Approaches included 79 DAA (14%), 212 ABMS (39%), 180 modified Müller-Hardinge (33%), and 79 posterolateral (14%). The incidence of lateral femoral cutaneous nerve injury was more common with the DAA (P = 0.008), but no other clinically significant differences were noted among the groups.

CONCLUSION

The results of this study showed no clinically notable differences between the supine ABMS and other approaches. The supine ABMS approach is an acceptable approach in modern day THA when used by an experienced surgeon well-versed in the approach.

Robotic-assisted total hip arthroplasty: an economic analysis

Aim: To evaluate 90-day episode-of-care (EOC) resource consumption in robotic-assisted total hip arthroplasty (RATHA) versus manual total hip arthroplasty (mTHA). Methods: THA procedures were identified in Medicare 100% data. After propensity score matching 1:5, 938 RATHA and 4,670 mTHA cases were included. 90-day EOC cost, index costs, length of stay and post-index rehabilitation utilization were assessed. Results: RATHA patients were significantly less likely to have post-index inpatient rehabilitation or skilled nursing facility admissions and used fewer home health agency visits, compared with mTHA patients. Total 90-day EOC costs for RATHA patients were found to be US$785 less than those of mTHA patients (p = 0.0095). Conclusion: RATHA was associated with an overall lower 90-day EOC cost when compared with mTHA. The savings associated with RATHA were driven by reduced utilization and cost of post-index rehabilitation services.

A comparison of leg length discrepancy between direct anterior and anterolateral approaches in total hip arthroplasty

Background

Leg length discrepancy (LLD) after total hip arthroplasty (THA) is a known source of complications and a leading cause of litigation (J Bone Joint Surg Br 87:155–157, 2005). There are limited studies investigating surgical approach combined with the use of fluoroscopy intraoperatively and their potential effects on LLD after THA. The purpose of this study was to compare the direct anterior (DA) approach utilizing a fluoroscopic overlay technique and anterolateral (AL) approach and their potential effect on LLD.

Methods

We retrospectively reviewed 121 patients who had undergone primary THA from September 1, 2016 to November 1, 2018 by either DA or AL approach by two separate surgeons. Leg length discrepancies were measured on pre-operative post-anesthesia care unit (PACU) and on post-operative low anterior/posterior (AP) pelvis plain radiographs by two investigators blinded to each other’s measurements. To confirm inter-observer and intra-observer reliability between LLD measurements amongst investigators, a Pearson correlation test was performed. The primary outcome measurement was leg length discrepancy (LLD).

Results

We observed LLD > 1.0 cm and LLD > 1.5 cm in the DA and AL groups. The DA approach group showed a mean LLD of 4.5 mm against 7.76 mm in the AL group (p < 0.00001). There was a significantly higher rate of LLD in the AL group as compared to the DA group (LLD> 1 cm (28% vs. 8%, p = 0.0037) and LLD > 1.5 cm (7% vs. 0%, p = 0.0096). The LLD measurements showed strong correlation in terms of inter-observer (r = 0.95) and intra-observer reliability (r = 0.99) between the two investigators (p < 0.001).

Conclusion

In our patient cohort, the DA approach with fluoroscopic overlay technique had less LLD in comparison with the AL approach, suggesting that intraoperative fluoroscopic use does have an impact on LLD.

Are high-risk patient and revision arthroplasty effective indications for closed-incisional negative-pressure wound therapy after total hip or knee arthroplasty? A systematic review and meta-analysis

To determine the effective indications of closed-incisional negative-pressure wound therapy (ciNPWT) following total hip or knee arthroplasty, this systematic review and meta-analysis was conducted. The systematic search was performed on MEDLINE, Embase, and Cochrane Library, and 11 studies were included. The studies comparing between ciNPWT and conventional dressings were categorised into following subgroups based on patient risk and revision procedures: routine vs high-risk patient; primary vs revision arthroplasty. Pooled estimates were calculated for wound complication and surgical site infection (SSI) rates in the subgroup analyses using Review Manager. In high-risk patients, the overall rates of wound complication (odds ratio [OR] = 0.38; 95% confidence interval [CI] 0.15-0.93; P = .030) and SSI (OR = 0.24; 95% CI = 0.09-0.64; P = .005) were significantly lower in the ciNPWT; however, there were no differences in routine patients. In cases involving revision arthroplasties, the overall rates of wound complication (OR = 0.33; 95% CI = 0.18-0.62; P < .001) and SSI (OR = 0.26; 95% CI = 0.11-0.66; P = .004) were significantly lower in the ciNPWT; however, there were no differences in cases involving primary arthroplasties. In summary, ciNPWT showed a positive effect in decreasing the rates of wound complication and SSI in high-risk patients and in revision arthroplasties.

Variation in greater trochanteric lateroversion: a risk factor for femoral stem varus in total hip arthroplasty

INTRODUCTION

Correct implant positioning is required to achieve adequate biomechanics. The greater trochanter is more medially or laterally positioned in some patients, known as trochanteric lateroversion. However, studies have not identified correlations between postoperative coronal alignment and variation in greater trochanteric lateroversion. The purpose of this study was to identify the effects of variation in greater trochanteric lateroversion on postoperative stem coronal alignment and to investigate other factors related to stem coronal alignment.

METHODS

A total of 213 hips in 149 patients who underwent total hip arthroplasty were included in this prospective study. The greater trochanters were categorised into 5 groups according to the degree of variation in greater trochanteric lateroversion, and the stem coronal alignment angle and stem fit were measured on anteroposterior radiographs.

RESULTS

Postoperative stem varus was positively correlated with greater trochanteric lateroversion (r = 0.26065, p = 0.0001) and negatively correlated with the stem fit (r = -0.16568, p = 0.0155).

DISCUSSION

Excessive variation in greater trochanteric lateroversion was a risk factor for femoral stem varus, and the stem varus position was always accompanied by inadequate canal filling. When the tip of the trochanteric overhang exceeded the centreline of the femoral canal, the influence of lateroversion of the greater trochanter on the femoral stem remarkably increased. Appropriate measures should be implemented to avoid a stem varus position and inappropriate stem fit.

Hip arthroscopy following contralateral total hip arthroplasty: a multicenter matched-pair study

The purpose of this study was to determine if patients undergoing hip arthroscopy for labral pathology with contralateral total hip arthroplasty (THA) have a difference in revision surgeries or patient-reported outcomes (PROs) when compared with those patients undergoing hip arthroscopy for labral pathology with a native contralateral hip. A retrospective review was performed for patients that were undergoing hip arthroscopy between 2008 and 2015. Patients were included in the study group if they met the following inclusion criteria: Tönnis Grade 0 or 1, hip labral pathology, previous contralateral THA, and greater than 2-year follow-up with completion of all PROs or conversion to a THA. Exclusion criteria included the previous surgical history on ipsilateral hip, peritrochanteric or deep gluteal space arthroscopy performed concomitantly, or dysplasia [Lateral Center Edge Angle (LCEA) < 20°]. A 3:1 matched-pair study was conducted. Multiple PRO scores were recorded for both groups. There was no statistically significant difference in the modified Harris hip score, non-arthritic hip score, hip outcome score-sports specific sub-scale, visual analog pain score and patient satisfaction scores between both groups. However, the study group was noted to have six patients converted to THA (67%) at an average of 30 months post-operatively, compared with only four patients (15%) in the control group (P = 0.006). Hip arthroscopy cannot be currently recommended in patients who have undergone contralateral THA due to the high conversion to THA (67%).

Acetabular cup orientation and postoperative leg length discrepancy in patients undergoing elective total hip arthroplasty via a direct anterior and anterolateral approaches

Background

Total hip arthroplasty (THA) is considered a successful surgical procedure. It can be performed by several surgical approaches. Although the posterior and anterolateral approaches are the most common, there has been increased interest in the direct anterior approach. The goal of the present study is to compare postoperative leg length discrepancy and acetabular cup orientation among patients who underwent total hip arthroplasty through a direct anterior (DAA) and anterolateral (ALA) approaches.

Methods

The study included 172 patients undergoing an elective THA by a single surgeon at our institution within the study period. Ninety-eight arthroplasties were performed through the ALA and 74 arthroplasties through the DAA. Preoperative planning was performed for all patients. Assessment of the two groups included the following postoperative parameters: abduction angle, cup anteversion angle and leg length discrepancy (LLD). Additional analysis was done to evaluate component positioning by comparing deviation from the Lewinnek zone of safety in both approaches.

Results

For the DAA the absolute LLD was 11 mm, ranging from -6 mm to 5 mm. For the ALA, the absolute LLD was 36 mm, ranging from -22 mm to 14 mm. None of the DAA patients had an absolute LLD greater than 6 mm. Comparatively, 7.4% of the ALA group exceeded 6 mm of LLD in addition to 2.1% with LLD greater than 10 mm. 15% of the ALA group resided out of the Lewinnek abduction zone compared to 3% of the DAA group (P = 0.016). 17% of the ALA group were out of the Lewinnek anteversion zone as opposed to 8% of the DAA group (P = 0.094).

Conclusion

Our study demonstrates good component positioning outcomes and LLD values in patients following THA through the DAA compared to the ALA.

Prospective Cohort Study on the Employment Status of Working Age Patients After Recovery From Ankle Arthritis Surgery

BACKGROUND

People who are affected by end-stage ankle arthritis are as disabled as those suffering from arthritis in other main articulations of the lower extremity. Once these patients become unable to perform their job duties, they leave the workforce and require financial aid from government agencies, which represents a considerable economic burden. Regardless of whether arthrodesis or arthroplasty is performed, we hypothesized that patients younger than 55 years at the time of surgery should be able to return to work within 2 years and require less social assistance.

METHODS

Patients from 2002 to 2014 included in the nationwide prospective Ankle Reconstruction Database treated for end-stage ankle arthritis with a total ankle replacement or an ankle arthrodesis and younger than 55 years at the time of surgery were included. This study used a standard preoperative survey (AAOS, SF-36) along with the same survey filled by patients in intervals up to 2 years postoperatively. Their employment status was determined at each time point. Participation in third-party wage assistance programs was recorded. This cohort had 194 patients with an average age of 47.0 ± 7.2 years and was balanced in terms of sex (104 female) and side (94 left).

RESULTS

The employment rate prior to surgery was 56%, which increased to 62% at the 2-year postoperative mark. With regards to worker's compensation, disability, and social security, 20% of patients left all subsidized programs whereas 4% entered at least 1 which is significant (P < .05).

CONCLUSION

The 2-year follow-up after tibiotalar arthrodesis/arthroplasty in patients younger than 55 years showed that significantly more people were able to leave subsidized work assistance programs than enroll in them.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Development and Evaluation of a Preoperative Risk Calculator for Periprosthetic Joint Infection Following Total Joint Arthroplasty

BACKGROUND

Preoperative identification of patients at risk for periprosthetic joint infection (PJI) following total hip arthroplasty (THA) or total knee arthroplasty (TKA) is important for patient optimization and targeted prevention. The purpose of this study was to create a preoperative PJI risk calculator for assessing a patient's individual risk of developing (1) any PJI, (2) PJI caused by Staphylococcus aureus, and (3) PJI caused by antibiotic-resistant organisms.

METHODS

A retrospective review was performed of 27,717 patients (12,086 TKAs and 31,167 THAs), including 1,035 with confirmed PJI, who were treated at a single institution from 2000 to 2014. A total of 42 risk factors, including patient characteristics and surgical variables, were evaluated with a multivariate analysis in which coefficients were scaled to produce integer scores. External validation was performed with use of data on 29,252 patients who had undergone total joint arthroplasty (TJA) at an independent institution.

RESULTS

Of the 42 risk factors studied, 25 were found not to be significant risk factors for PJI. The most influential of the remaining 17 included a previous open surgical procedure, drug abuse, a revision procedure, and human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). The areas under the curves were 0.83 and 0.84 for any PJI, 0.86 and 0.83 for antibiotic-resistant PJI, and 0.86 and 0.73 for S. aureus PJI in the internal and external validation models, respectively. The rates of PJI were 0.56% and 0.61% in the lowest decile of risk scores and 15.85% and 20.63% in the highest decile.

CONCLUSIONS

In this large-cohort study, we were able to identify and validate risk factors and their relative weights for predicting PJI. Factors such as prior surgical procedures and high-risk comorbidities should be considered when determining whether TJA is indicated and when counseling patients.

LEVEL OF EVIDENCE

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

The Cost-Effectiveness of Total Hip Arthroplasty in Patients 80 Years of Age and Older

BACKGROUND

This study investigates the cost-effectiveness of total hip arthroplasty (THA) in patients 80 years old.

METHODS

A Markov, state-transition model projecting lifetime costs and quality-adjusted life years (QALYs) was constructed to determine cost-effectiveness from a societal perspective. Costs (in 2016 US dollars), health state utilities, and state transition probabilities were obtained from published literature. Primary outcome was incremental cost-effectiveness ratio, with a willingness-to-pay threshold of $100,000/QALY. Sensitivity analyses were performed to evaluate parameter assumptions.

RESULTS

At our base-case values, THA was cost-effective compared to non-operative treatment with a total lifetime accrued cost of $186,444 vs $182,732, and a higher lifetime accrued utility (5.60 vs 5.09). Cost per QALY for THA was $33,318 vs $35,914 for non-operative management, and the incremental cost-effectiveness ratio was $7307 per QALY. Sensitivity analysis demonstrated THA to be cost-effective with a utility of successful primary THA above 0.67, a peri-operative mortality risk below 0.14, and a risk of primary THA failure below 0.14. Analysis further demonstrated that THA is a cost-effective option below a base-rate mortality threshold of 0.19, corresponding to the average base-rate mortality of a 93-year-old individual. Markov cohort analysis indicated that for patients undergoing THA at age 80 there was an approximate 28% reduction in total lifetime long-term assisted living expenditure compared to non-operatively managed patients with end-stage hip osteoarthritis.

CONCLUSION

The results of our model demonstrate that THA is a cost-effective option compared to non-operative management in patients ≥80 years old. This analysis may inform policy regarding THA in elderly patients.

Comparison of outcome measures and complication rates following three different approaches for primary total hip arthroplasty: a pragmatic randomised controlled trial

BACKGROUND

Total hip arthroplasty is one of the most commonly performed surgical procedures worldwide. There are a number of surgical approaches for total hip arthroplasty and no high-level evidence supporting one approach over the other. Each approach has its unique benefits and drawbacks. This trial aims to directly compare the three most common surgical approaches for total hip arthroplasty.

METHODS/DESIGN

This is a single-centre study conducted at Western Health, Melbourne, Australia; a large metropolitan centre. It is a pragmatic, parallel three-arm, randomised controlled trial. Sample size will be 243 participants (81 in each group). Randomisation will be secure, web-based and managed by an independent statistician. Patients and research team will be blinded pre-operatively, but not post-operatively. Intervention will be either direct anterior, lateral or posterior approach for total hip arthroplasty, and the three arms will be directly compared. Participants will be aged over 18 years, able to provide informed consent and recruited from our outpatients. Patients who are having revision surgery or have indications for hip replacement other than osteoarthritis (i.e., fracture, malignancy, development dysplasia) will be excluded from the trial. The Oxford Hip Score will be determined for patients pre-operatively and 6 weeks, 6, 12 and 24 months post-operatively. The Oxford Hip Score at 24 months will be the primary outcome measure. Secondary outcome measures will be dislocation, infection, intraoperative and peri-prosthetic fracture rate, length of hospital stay and pain level, reported using a visual analogue scale.

DISCUSSION

Many studies have evaluated approaches for total hip arthroplasty and arthroplasty registries worldwide are now collecting this data. However no study to date has compared these three common approaches directly in a randomised fashion. No trial has used patient-reported outcome measures to evaluate success. This pragmatic study aims to identify differences in patient perception of total hip arthroplasty depending on surgical approach.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12617000272392 . Registered on 22 February 2017.

A Prospective Randomized Trial of Mini-Incision Posterior and 2-Incision Total Hip Arthroplasty: Minimum 5-Year Follow-Up

BACKGROUND

We previously described the results of a randomized controlled trial of mini-posterior vs 2-incision total hip arthroplasty and were unable to demonstrate significant differences in early outcomes. As less-invasive anterior approaches remain popular, the purpose of this report was to re-examine the outcomes at a minimum 5-year follow-up.

METHODS

Seventy-two patients undergoing primary total hip arthroplasty were randomized to a mini-posterior or 2-incision approach. Complications, revisions, and clinical outcome measures were compared. Radiographs were reviewed for implant loosening. A power analysis using a minimal clinically important difference value of 6 points for the Harris hip score revealed 28 patients required per group.

RESULTS

At a mean of 8.2 years (range, 5-10 years), 6 patients died without revision surgery and 63 of 66 living patients were reviewed. There were 6 total failures, 3 in each group. For unrevised patients, there were no significant differences between groups (posterior vs 2-incision) in the Harris hip score (95.5 ± 3.5 vs 95.7 ± 6.3; P = .88), 12-item Short Form Survey physical composite score (50.5 ± 8.5 vs 49.0 ± 9.1; P = .53), 12-item Short Form Survey mental composite score (57.3 ± 4.1 vs 55.4 ± 8.0; P = .25), or single assessment numeric evaluation score (97.1 ± 3.7 vs 97.8 ± 5.2; P = .55).

CONCLUSION

We found no differences in midterm outcomes between the 2 approaches. Given the increased complexity, operative time, and need for fluoroscopy with the 2-incision approach combined with equivalent early and midterm outcomes, the 2-incision approach has been abandoned in the senior author's practice.

The Impact of Surgical Technique on Patient Reported Outcome Measures and Early Complications After Total Hip Arthroplasty

BACKGROUND

This study examines patient and surgeon reported outcome measures, complications during index admission, length of stay (LOS), and discharge disposition in a series of total hip replacements (THR) performed via the direct anterior (DA) or posterolateral (PL) approach.

METHODS

Five surgeons performed 2698 total hip replacements (1457 DA vs 1241 PL) between January 2010 and June 2015. Complications during index admission were recorded using billing and claims data. Harris Hip Scores (HHS) and Hip disability and Osteoarthritis Outcome Scores (HOOS) were collected in a subset of patients.

RESULTS

Patients in the DA group had shorter LOS (2.3 DA vs 2.7 PL days, P < .001) and a larger proportion of patient discharges to home (79.0% DA vs 68.7% PL, P < .001). Surgical (0.75% DA vs 0.73% PL, P = .961) and medical (8.4% DA vs 8.1% PL, P = .766) complications during index admission were equivalent between groups. HHS (n = 462) favored the DA group at an early follow-up (P < .001), but did not differ at 1 year (P = .478). Logistic regression revealed that patients in the DA group were more likely to report no pain, no limp, walk unlimited distances, and climb stairs without the use of the railing at 3- to 6-month follow-up (P < .001). HOOSs were equivalent at all follow-ups regardless of approach.

CONCLUSION

Patients in the DA group had shorter LOS and were more likely to be discharged home. The DA group had better HHS at 3- to 6-month follow-up than patients in the PL group, with no difference in medical or surgical complications during index admission.

Patient-reported health outcomes after total hip and knee surgery in a Dutch University Hospital Setting: results of twenty years clinical registry

Background

Patient-Reported Outcome (PRO) measurement is a method for measuring perceptions of patients on their health and quality of life. The aim of this paper is to present the results of PRO measurements in total hip and knee replacement as routinely collected during 20 years of surgery in a university hospital setting.

Methods

Data of consecutive patients between 1993 and 2014 were collected. Health outcomes were measured pre-surgery and at 3, 6, and 12 months post-surgery. Outcomes for hip replacement were measured with the Harris Hip Score (HHS) and Oxford Hip Score (OHS). Outcomes for knee replacement were measured with the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the Knee Society Score (KSS). A Visual Analog Scale (VAS) for pain was used. Absolute and relative Minimal Clinically Important Differences (MCID) were estimated. Generalized estimating equation analysis was used for estimating mean outcomes. Trends over time were analyzed.

Results

The database contained 2,089 patients with hip replacement, and 704 patients with knee replacement. Mean HHS and OHS scores in primary hip replacement at 12 months post-surgery were 86.7 (SD: 14.5) and 41.1 (SD: 7.5) respectively. Improvements on the HHS based on absolute MCID was lower for revisions compared to primary hip replacements, with 72.4% and 87.0% respectively. Mean WOMAC and KSS scores in knee replacement at 12 months post-surgery were 21.5 (SD: 18.2) and 67.0 (SD: 26.4) respectively. Improvements based on absolute MCID were lowest for the KSS (62.6%) and highest for VAS pain (85.6%). Trend analysis showed a difference in 1 out of 24 comparisons in hip replacement and in 2 out of 9 comparisons in knee replacement.

Conclusions

The functional status of a large cohort of patients significantly improved after hip and knee replacement based on routine data collection. Our study shows the feasibility of the routine collection of PRO data in patients with total hip and knee replacement. The use of PRO data provides opportunities for continuous quality improvement.

Effect of Acetabular Component Positioning on Functional Outcomes in Primary Total Hip Arthroplasty

BACKGROUND

Acetabular component positioning is crucial to a successful total hip arthroplasty (THA). This study evaluated the effect of absolute acetabular component position as well as acetabular position relative to bony anatomy on patient-reported functional outcomes after primary THA.

METHODS

Primary, press fit, hemispherical metal-on-polyethylene THA performed between 2003 and 2011 were analyzed. Western Ontario and McMaster Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), Short Form-12 scores, and radiographs between 2 and 3 years after the index procedure were assessed.

RESULTS

Of the 1241 primary THA included, the mean abduction and anteversion angles were 44.4 ± 6.94 and 21.7 ± 11.9 degrees, respectively. The mean anterior and lateral overhang were 1.9 ± 3.6 and 2.5 ± 3.4 mm, respectively. There was no correlation between functional outcomes and acetabular inclination. A weak positive correlation between anteversion and HHS (P < .001) and WOMAC (P = .02) scores was found. For relative position, anterior overhang of the acetabular component beyond the bone resulted in inferior Short Form-12 physical function (P = .001), HHS (P = .004), and WOMAC (P < .001) scores compared to those with bony coverage. Mean HHS pain score was 41.20 ± 5.69 in patients with lateral overhang and 41.97 ± 5.04 in those who had bony coverage of the lateral edge of the acetabular component (P = .02).

CONCLUSION

The tribology and biomechanics of acetabular component position have been extensively studied without examination of how it affects patient function. Although statistical significance was seen, clinical outcome scores were not sensitive enough to show a clinically significant effect of the absolute or relative position of the acetabular component.

Body Mass Index Class Is Independently Associated With Health-Related Quality of Life After Primary Total Hip Arthroplasty: An Institutional Registry-Based Study

BACKGROUND

The purpose of this study was to compare the health-related quality of life (HRQoL) of patients across World Health Organization (WHO) body mass index (BMI) classes before and after total hip arthroplasty (THA).

METHODS

Patients with end-stage hip osteoarthritis who received elective primary unilateral THA were identified through an institutional registry and categorized based on the World Health Organization BMI classification. Age, sex, laterality, year of surgery, and Charlson-Deyo comorbidity index were recorded. The primary outcome was the EQ-5D-3L index and visual analog scale (EQ-VAS) scores at 2 years postoperatively. Inferential statistics and regression analyses were performed to determine associations between BMI classes and HRQoL.

RESULTS

EQ-5D-3L scores at baseline and at 2 years were statistically different across BMI classes, with higher EQ-VAS and index scores in patients with lower BMI. There was no difference observed for the 2-year change in EQ-VAS scores, but there was a statistically greater increase in index scores for more obese patients. In the regression analyses, there were statistically significant negative effect estimates for EQ-VAS and index scores associated with increasing BMI class.

CONCLUSION

BMI class is independently associated with lower HRQoL scores 2 years after primary THA. While absolute scores in obese patients were lower than in nonobese patients, obese patients enjoyed more positive changes in EQ-5D index scores after THA. These results may provide the most detailed information on how BMI influences HRQoL before and after THA, and they are relevant to future economic decision analyses on the topic.

Estimating the Societal Benefits of THA After Accounting for Work Status and Productivity: A Markov Model Approach

BACKGROUND

Demand for total hip arthroplasty (THA) is high and expected to continue to grow during the next decade. Although much of this growth includes working-aged patients, cost-effectiveness studies on THA have not fully incorporated the productivity effects from surgery.

QUESTIONS/PURPOSES

We asked: (1) What is the expected effect of THA on patients' employment and earnings? (2) How does accounting for these effects influence the cost-effectiveness of THA relative to nonsurgical treatment?

METHODS

Taking a societal perspective, we used a Markov model to assess the overall cost-effectiveness of THA compared with nonsurgical treatment. We estimated direct medical costs using Medicare claims data and indirect costs (employment status and worker earnings) using regression models and nonparametric simulations. For direct costs, we estimated average spending 1 year before and after surgery. Spending estimates included physician and related services, hospital inpatient and outpatient care, and postacute care. For indirect costs, we estimated the relationship between functional status and productivity, using data from the National Health Interview Survey and regression analysis. Using regression coefficients and patient survey data, we ran a nonparametric simulation to estimate productivity (probability of working multiplied by earnings if working minus the value of missed work days) before and after THA. We used the Australian Orthopaedic Association National Joint Replacement Registry to obtain revision rates because it contained osteoarthritis-specific THA revision rates by age and gender, which were unavailable in other registry reports. Other model assumptions were extracted from a previously published cost-effectiveness analysis that included a comprehensive literature review. We incorporated all parameter estimates into Markov models to assess THA effects on quality-adjusted life years and lifetime costs. We conducted threshold and sensitivity analyses on direct costs, indirect costs, and revision rates to assess the robustness of our Markov model results.

RESULTS

Compared with nonsurgical treatments, THA increased average annual productivity of patients by USD 9503 (95% CI, USD 1446-USD 17,812). We found that THA increases average lifetime direct costs by USD 30,365, which were offset by USD 63,314 in lifetime savings from increased productivity. With net societal savings of USD 32,948 per patient, total lifetime societal savings were estimated at almost USD 10 billion from more than 300,000 THAs performed in the United States each year.

CONCLUSIONS

Using a Markov model approach, we show that THA produces societal benefits that can offset the costs of THA. When comparing THA with other nonsurgical treatments, policymakers should consider the long-term benefits associated with increased productivity from surgery.

LEVEL OF EVIDENCE

Level III, economic and decision analysis.

Does Surgical Approach Affect Patient-reported Function After Primary THA?

BACKGROUND

Total hip arthroplasty (THA) relieves pain and improves physical function in patients with hip osteoarthritis, but requires a year or more for full postoperative recovery. Proponents of intermuscular surgical approaches believe that the direct-anterior approach may restore physical function more quickly than transgluteal approaches, perhaps because of diminished muscle trauma. To evaluate this, we compared patient-reported physical function and other outcome metrics during the first year after surgery between groups of patients who underwent primary THA either through the direct-anterior approach or posterior approach.

QUESTIONS/PURPOSES

We asked: (1) Is a primary THA using a direct-anterior approach associated with better patient-reported physical function at early postoperative times (1 and 3 months) compared with a THA performed through the posterior approach? (2) Is the direct-anterior approach THA associated with shorter operative times and higher rates of noninstitutional discharge than a posterior approach THA?

METHODS

Between October 2008 and February 2010, an arthroplasty fellowship-trained surgeon performed 135 THAs. All 135 were performed using the posterior approach. During that period, we used this approach when patients had any moderate to severe degenerative joint disease of the hip attributable to any type of arthritis refractory to nonoperative treatment measures. Of the patients who were treated with this approach, 21 (17%; 23 hips) were lost to followup, whereas 109 (83%; 112 hips) were available for followup at 1 year. Between February and September 2011, the same surgeon performed 86 THAs. All 86 were performed using the direct-anterior approach. During that period, we used this approach when patients with all types of moderate to severe degenerative joint disease had nonoperative treatment measures fail. Of the patients who were treated with this approach, 35 (41%; 35 hips) were lost to followup, whereas 51 (59%; 51 hips) were available for followup at 1 year. THAs during the surgeon's direct-anterior approach learning period (February 2010 through January 2011) were excluded because both approaches were being used selectively depending on patient characteristics. Clinical outcomes included operative blood loss; allogeneic transfusion; adverse events; patient-reported Veterans RAND-12 Physical (PCS) and Mental Component Summary (MCS) scores, and University of California Los Angeles (UCLA) activity scores at 1 month, 3 months, and 1 year after surgery. Resource utilization outcomes included operative time, length of stay, and discharge disposition (home versus institution). Outcomes were compared using logistic and linear regression techniques.

RESULTS

After controlling for relevant confounding variables including age, sex, and BMI, the direct-anterior approach was associated with worse adjusted MCS changes 1 and 3 months after surgery (1-month score change, -9; 95% CI, -13 to -5; standard error, 2), compared with the posterior approach (3-month score change, -9; 95% CI, -14 to -3; standard error, 3) (both p < 0.001), while the direct-anterior approach was associated with greater PCS improvement at 3 months compared with the posterior approach (score change, 6; 95% CI, 2-10; standard error, 2; p = 0.008). There were no differences in adjusted PCS at either 1 month or 12 months, and no clinically important differences in UCLA scores. Although the PCS score differences are greater than the minimum clinically important difference of 5 points for this endpoint, the clinical importance of such a small effect is questionable. At 1 year after THA, there were no intergroup differences in self-reported physical function, although both groups had significant loss-to-followup at that time. Operative time (skin incision to skin closure) between the two groups did not differ (81 versus 79 minutes; p = 0.411). Mean surgical blood loss (403 versus 293 mL; p < 0.001; adjusted, 119 more mL; 95% CI, 79-160; p < 0.001) and in-hospital transfusion rates (direct-anterior approach, 20% [17/86] versus posterior approach, 10% [14/135], p = 0.050; adjusted odds ratio, 3.6; 95% CI, 1.3-10.1; p = 0.016) were higher in the direct-anterior approach group. With the numbers available, there was no difference in the frequency of adverse events between groups when comparing intraoperative complications, perioperative Technical Expert Panel complications, and other non-Technical Expert Panel complications within 1 year of surgery, although this study was not adequately powered to detect differences in rare adverse events.

CONCLUSIONS

With suitable experience, the direct-anterior approach can be performed with expected results similar to those of the posterior approach. There may be transient and small benefits to the direct-anterior approach, including improved physical function at 3 months after surgery. However, the greater operative blood loss and greater likelihood of blood transfusions, even when the surgeon is experienced, may be a disadvantage. Given some of the kinds of bias present that we found, including loss to followup, the conclusions we present should be considered preliminary, but it appears that any benefits that accrue to the patients who had the direct-anterior approach would be transient and modest. Prospective randomized studies on the topic are needed to address the differences between surgical approaches more definitively.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Primary vs Conversion Total Hip Arthroplasty: A Cost Analysis

INTRODUCTION

Increasing hip fracture incidence in the United States is leading to higher occurrences of conversion total hip arthroplasty (THA) for failed surgical treatment of the hip. In spite of studies showing higher complication rates in conversion THA, the Centers for Medicare and Medicaid services currently bundles conversion and primary THA under the same diagnosis-related group. We examined the cost of treatment of conversion THA compared with primary THA. Our hypothesis is that conversion THA will have higher cost and resource use than primary THA.

METHODS

Fifty-one consecutive conversion THA patients (Current Procedure Terminology code 27132) and 105 matched primary THA patients (Current Procedure Terminology code 27130) were included in this study. The natural log-transformed costs for conversion and primary THA were compared using regression analysis. Age, gender, body mass index, American Society of Anesthesiologist, Charlson comorbidity score, and smoker status were controlled in the analysis. Conversion THA subgroups formed based on etiology were compared using analysis of variance analysis.

RESULTS

Conversion and primary THAs were determined to be significantly different (P<.05) and greater in the following costs: hospital operating direct cost (29.2% greater), hospital operating total cost (28.8% greater), direct hospital cost (24.7% greater), and total hospital cost (26.4% greater).

CONCLUSIONS

Based on greater hospital operating direct cost, hospital operating total cost, direct hospital cost, and total hospital cost, conversion THA has significantly greater cost and resource use than primary THA. In order to prevent disincentives for treating these complex surgical patients, reclassification of conversion THA is needed, as they do not fit together with primary THA.

The Cost-Utility of Total Hip Arthroplasty: Earlier Intervention, Improved Economics

We estimated the cost of Quality-Adjusted-Life-Years gained according to preoperative disease severity. We studied 159 primary unilateral THA, mean follow-up: 4 years. A median split of preoperative WOMAC scores was done to set apart a low (better) and a high (worse) score group. The groups with worse preoperative WOMAC were consistently associated with a less cost-effective intervention. The highest mean cost-effectiveness was achieved by patients with better WOMAC-total ($8256.32/QALY-gained). As patients aged, the cost-effectiveness of THA decreased. Patients 75 years of age or older and with worse scores had the least cost-effective interventions ($25,937.33/QALY-gained). THA remains a very cost-effective intervention even when performed in older "sicker" patients. Waiting for the patient to deteriorate will make the intervention more "expensive".

Current status of cost utility analyses in total joint arthroplasty: a systematic review

BACKGROUND

Total joint arthroplasty (TJA), although considered to be highly beneficial, is associated with substantial costs to the US healthcare system. Cost utility analysis has become an increasingly important means to objectively evaluate the value of a healthcare intervention from the perspective of both extending the quantity and improving the quality of life. Relatively little is known about the overall cost utility analysis evidence base in TJA.

QUESTIONS/PURPOSES

The goals of this review were to (1) determine the cost utility of TJA interventions; (2) critically assess the quality of published US-based cost utility analyses using the Quality of Health Economic Studies instrument; and (3) determine what characteristics were common among studies receiving a high quality score.

METHODS

A systematic review of the literature using the MEDLINE database was performed to compile findings and critically appraise US-based cost utility analysis studies for total hip and knee arthroplasty. Based on review of 676 identified articles, 23 studies were included. We used the Quality of Health Economic Studies instrument to assess study quality and one-sided Fisher's exact tests were applied to analyze the predictors of high-quality cost utility analysis.

RESULTS

Very few studies compare the cost utility of TJA versus nonoperative intervention; however, the available evidence suggests that TJA can be cost-saving and is highly cost-effective compared with conservative management of end-stage arthritis. The majority of identified studies are focused on the cost utility of new implant technologies or comparisons among surgical alternatives. These studies suggest that the upfront costs associated with new technologies are cost-effective when there is a major reduction in a future cost. The quality of identified studies is quite high (Quality of Health Economic Studies Instrument score: mean 86.5; range, 63-100). National funding source (p = 0.095) and lifetime horizon for analysis (p = 0.07) correlate with high-quality evidence but do not reach significance.

CONCLUSIONS

Over the past 15 years, there has been a major increase in the volume of cost utility analyses published in total hip and knee arthroplasty. The quality of cost utility analyses published during that period is good. As increasing attention is paid to value in US health care, more attention should be paid to understanding the cost utility of TJA compared with nonoperative treatment modalities. Future studies may also look to incorporate patient willingness to pay.

Short-term complications have more effect on cost-effectiveness of THA than implant longevity

BACKGROUND

Outcomes research in THA has focused largely on long-term implant survivorship as a primary outcome and emphasized the development of new implant technologies. In contrast, strategies to improve short-term outcomes, such as the frequencies of periprosthetic joint infections and unplanned readmissions, have received less attention.

QUESTIONS/PURPOSES

We asked whether reductions in periprosthetic joint infections and early readmissions would have greater influence on the net monetary benefit (a summation of lifetime cost and quality of life) for THA compared with equivalent reductions in aseptic loosening.

METHODS

A Markov model was created using decision-analysis software with six health states and death to represent seven major potential outcomes of THA. We compared the effect of a 10% reduction in each of the following outcomes: (1) periprosthetic joint infection, (2) hospital readmission, and (3) aseptic loosening. Procedure costs (not charges) were derived from our hospital cost-accounting system. Probabilities were derived primarily from the Australian Orthopaedic Association National Joint Replacement Registry, and utilities were estimated from a previous study at our institution using the time trade-off method. The primary outcome of the study is the net monetary benefit, which combines the reductions in cost and improvement in health-related quality of life in a single metric. Quality of life is expressed in quality-adjusted life years (QALYs), which are calculated by multiplying the utility of a health state (ranging from 0 to 1) by the duration of time in the health state. The cost and QALYs are reported separately as secondary outcomes. One-way and multivariate sensitivity analyses were performed including a probabilistic sensitivity analysis to account for uncertainty in model inputs.

RESULTS

The net monetary benefit for a 10% reduction in periprosthetic joint infections was USD 278 (95% CI, USD 239-295) per index procedure compared with USD 174 (95% CI, USD 150-185) and USD 113 (95% CI, USD 94-129) for reductions in aseptic loosening and early readmission, respectively. Compared with the base case, reductions in cost associated with a 10% reduction in periprosthetic joint infections, early readmissions, and aseptic loosening were USD 98, USD 93, and USD 75 per index procedure, respectively. The increase in QALYs for an equivalent reduction in periprosthetic joint infections, aseptic loosening, and early readmissions were 0.0036, 0.002, and 0.0004 QALYs, respectively. Results were most sensitive to age, baseline rate of readmission, periprosthetic joint infection, aseptic loosening, and the costs of readmission and revision THA.

CONCLUSIONS

Strategies to reduce periprosthetic joint infections may have a greater effect on the cost and long-term effectiveness of THA than further enhancements in implant longevity. Reductions in the rate of readmission resulted in greater reductions in cost but not quality-of-life, and therefore had smaller effect on the net monetary benefit compared with aseptic loosening. Surgeons preferentially should engage in strategies focusing on periprosthetic joint infections to improve the value of THA care.

LEVEL OF EVIDENCE

Level II, economic and decision analysis.

Preoperative pain level and patient expectation predict hospital length of stay after total hip arthroplasty

The purpose of this study was to identify preoperative predictors of length of stay after primary total hip arthroplasty in a patient population reflecting current trends toward shorter hospitalization and using readily obtainable factors that do not require scoring systems. A retrospective review of 112 consecutive patients was performed. High preoperative pain level and patient expectation of discharge to extended care facilities (ECFs) were the only significant multivariable predictors of hospitalization extending beyond 2 days (P=0.001 and P<0.001 respectively). Patient expectation remained significant after adjusting for Medicare's 3-day requirement for discharge to ECFs (P<0.001). The study was adequately powered to analyze the variables in the multivariable logistic regression model, which had a concordance index of 0.857.

Initial hospital-related cost comparison of total ankle replacement and ankle fusion with hip and knee joint replacement

BACKGROUND

Total hip and knee arthroplasty (THA and TKA) are accessible to patients with end-stage hip and knee arthritis in most health care systems. The availability of total ankle arthroplasty (TAA) to patients with end-stage ankle arthritis is often restricted because of prosthesis cost. Ankle fusion (AF) is often offered as the only alternative. Patients should have equal access to procedures that are equivalent in total cost. We compared total costs of TAA, AF, THA, and TKA for similar cohorts in a government-funded teaching hospital.

METHODS

A subset of 13 TAA and 13 AF patients were selected from the Canadian Orthopaedic Foot and Ankle Society Prospective Ankle Reconstruction Database, and 13 THA and 13 TKA patients were randomly selected from the Canadian Joint Replacement Registry. Total cost was estimated from operating room time, hospital stay, surgeon billing, and equipment used.

RESULTS

Mean total cost associated with TAA was $13,500 ± 1000 and was the same as THA ($14,500 ± 1500) and TKA ($12,500 ± 1000). Mean total cost associated with AF was significantly less at $5500 ± 500. Mean operating room time was longer, but mean hospital stay was shorter for the ankle procedures compared with THA and TKA.

CONCLUSION

All arthroplasties had similar total costs. Total ankle arthroplasty should not be denied based on prosthetic cost alone, as total procedure cost is equivalent to THA and TKA. We believe ankle fusion is a less expensive and preferable alternative for some patient groups.

Anterior vs. posterior approach for total hip arthroplasty, a systematic review and meta-analysis

The objective of this study is to compare the clinical, radiographic and surgical outcomes among patients undergoing primary THA performed via the anterior versus posterior approach. We searched numerous sources and eventually included 17 studies, totaling 2302 participants. In terms of post-operative pain and function, the anterior approach was significantly favored in 4 studies at short-term follow-up. Pooled estimates showed a significant difference in favor of the anterior approach in terms of length of stay and dislocations. Current evidence comparing outcomes following anterior versus posterior THA does not demonstrate clear superiority of either approach. Until more rigorous, randomized evidence is available, we recommend choice of surgical approach for THA be based on patient characteristics, surgeon experience and surgeon and patient preference.

Total hip replacement: a systematic review and meta-analysis on mid-term quality of life

OBJECTIVE

Total hip replacement (THR) is one of the most successful and frequently performed operations worldwide. Health-related quality of life (HRQOL) is a key outcome measure of surgery. We investigated mid-term HRQOL after THR in patients with osteoarthritis (OA).

DESIGN

A systematic review of clinical studies published after January 2000 was performed using strict eligibility criteria. Quality appraisal and data tabulation were performed using pre-determined forms. Data were synthesised by narrative review and random-effects meta-analysis using standardised response means. Tau(2) and I(2) values and Funnel plots were analysed.

RESULTS

20 studies were included. Mid-term post-operative HRQOL is superior compared to pre-operative status on qualitative and quantitative analysis. Pooled response means of total Harris Hip Score (HHS) (P < 0.00001) and combined pain (P = 0.00001) and physical function (P < 0.00001) domains of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and HHS improved markedly up to 7 years. Medical Outcomes Survey Short Form 36 shows physical functioning (PF) (P < 0.00001), bodily pain (BP) (P < 0.00001), role physical (P = 0.001), role emotional (P = 0.04), and social functioning (SF) (P = 0.03) were improved up to 7 years. General health (GH) (P = 0.29), mental health (MH) (P = 0.43), and vitality (P = 0.17) was similar. HRQOL is at least as good as reference populations in the first few years and subsequently plateaus or declines. Patient satisfaction and functional status was favourable. There was significant heterogeneity amongst all studies, but publication bias was low in pooled analysis.

CONCLUSION

THR confers significant mid-term HRQOL benefits across a broad range of health domains. Further studies based on consistent guidelines provided in this review are required.

Mortality, cost, and downstream disease of total hip arthroplasty patients in the medicare population

The purpose of this study is to compare the differences in downstream cost and health outcomes between Medicare hip OA patients who undergo total hip arthroplasty (THA) and those who do not. All OA patients in the Medicare 5% sample (1998-2009) were separated into non-THA and THA groups. Differences in costs and risk ratios for mortality and new disease diagnoses were adjusted using logistic regression for age, sex, race, socioeconomic status, region, and Charlson score. Mortality, heart failure, depression, and diabetes were all reduced in the THA group, though there was an increased risk for atherosclerosis in the short term. The potential for selection bias was investigated with two separate propensity score analyses. This study demonstrates the potential benefit of THA in reducing mortality and improving aspects of overall health in OA patients.

Primary total hip arthroplasty: health related quality of life outcomes

PURPOSE

The health related quality of life (HRQoL) outcomes of total hip arthroplasty (THA) present a pertinent and clinically important problem in modern orthopaedics. Our goal was to report and compare the health-related outcomes after THA in respect to type of fixation in patients with hip osteoarthritis (H-OA) one year after operation.

METHODS

A total of 145 patients with H-OA who received THA were evaluated. Uncemented and cemented subjects were evaluated using generic measures, i.e. the EQ-5D questionnaire, and the disease-specific measures designed by the authors, i.e. the Total Hip Arthroplasty Questionnaire (THAQ). Obtained data was statistically processed at the level of pain, functionality and general health perception. Patient-reported outcomes were measured differences between pre-operative measures and those at one-year follow-up visit.

RESULTS

Significant improvement in health outcomes was reached in both groups regardless of the type of fixation (p < 0.001). Uncemented fixation exhibited better results for EQ-5DINDEX, pain (p = 0.004) and self-care on EQ-5D (p = 0.043), as well as increased magnitude of change for functionality on THAQ (p = 0.002). However, additional analysis of the subset did not reveal a significant difference between cemented vs. uncemented groups with regard to function on THAQ, but the significant difference on self-care and pain dimensions of EQ-5D remained.

CONCLUSIONS

Uncemented endoprosthesis generally achieved better short-term outcomes in some dimensions. However, painless mobility has been restored in most of the patients, regardless of the fixation type. Both methods reached good clinical outcomes in their respective domains; therefore, we would emphasise prevention of osteoarthritis and the quality of care as the more important predictors of good clinical outcomes.

Total hip arthroplasty in young females with congenital dislocation of the hip, radically improves their long-term quality of life

Eighty-two female patients with low dislocation (67 hips) or high dislocation (48 hips) were assessed using clinical scores and EQ-5D quality of life (QoL) questionnaire. Assessment was performed at the first to secondyear postoperatively and at the final follow-up, after a minimum of 12 years (12-37). Patients reported with a high EQ-5D health state VAS scale, VAS index and TTO index at 1 to 2 years follow-up (94,21/0,907/0,931) that remained considerably high despite the long-term follow-up (73,8/0,721/0,746). The scores for pain and range of motion presented with a statistically significant improvement at 1 to 2 years postoperatively and at the time of final follow-up. Function scores have declined with age. Total hip arthroplasty in CHD patients radically improves QoL for a long period of time.

Multiple biomarkers analysis for the early detection of prosthetic aseptic loosening of hip arthroplasty

PURPOSE

Our aim was to define the effect of multiple biomarkers of osteolysis or bone remodelling in the early detection of aseptic loosening (AL) of total hip arthroplasty (THA).

METHOD

One hundred subjects were recruited, including 31 candidates for revision THA (Late AL group), 15 patients who had undergone THA and had clinical and radiographic evidence of AL (early AL group), 19 patients with no sign of AL (stable group), and 40 healthy volunteers. Plasma levels of osteoprotegerin (OPG), receptor activator of nuclear factor-kappaB ligand (RANKL), cross-linked N-terminal telopeptide (NTX), procollagen I C-terminal extension peptide (PICP), tumour necrosis factor-alpha (TNF-α), and interleukin (IL)-1β1 were measured using an immunoenzymatic method. The outcomes of biomarkers were analysed separately and synthetically using Revman software.

RESULTS

The plasma level of OPG, RANKL, NTX, TNF-α, and IL-1β declined from late AL, early AL, stable to the healthy group, while the level of PICP inclined reversely. There was a significant difference in synthetic analysis of six biomarkers between the AL group and the stable group, and between the stable group and the healthy group (both p = 0.02). Heterogeneity of six biomarkers in either comparison was extremely low (both I(2) =0). Patients who had cemented implants had significantly higher levels of TNF-α than patients with cementless varieties (p = 0.042).

CONCLUSION

There was significant change in the plasma level of multiple biomarkers in patients with prosthetic AL of THA, especially in the cemented arthroplasties and in patients without traditional clinical or radiographic evidence of AL.

Health-related quality of life after total joint arthroplasty: a scoping review

A scoping review was completed to summarize the change in health status after THA and TKA. Although a recent study has performed a systematic review of functional recovery after THA,(61) we reviewed a broad topic of HRQL changes after total joint arthroplasty. This scoping review was not restricted by study design; however, the majority of studies were prospective single group, observational studies so that change over time could be reported. A variety of HRQL measures were used, including disease-specific, generic, and utility measures. We reported on 33 studies that met our inclusion criteria. Most studies’ primary outcomes were disease-specific measures. Not surprisingly, MCIDs were reported with recovery both short term and long term. These clinically relevant changes were accompanied with large effect sizes for pain and function using disease-specific measures such as the WOMAC. In general, smaller changes were reported with joint stiffness; however, this may also be related to inherent measurement properties of the WOMAC in that it uses two questions to evaluate stiffness. Overall, large effect sizes, in excess of 1.0, were seen not only short term but also long term, that is, more than a year after surgery. The changes may also be reflected in the low rate of complications reported with total joint arthroplasty.(62) The generic health measures showed a smaller magnitude of change, which is to be expected given the construct of these measures evaluate overall health and includes the effect of other health conditions. That being said, the largest changes were seen in those domains that were primary to total joint arthroplasty, pain and physical function. A challenge of evaluating change of health status after total joint arthroplasty is that each measure has individual strengths and limitations. This review introduced the measures and the MCIDs when available to evaluate clinical change. The derived MCIDs should be considered carefully because these values are dependent on a number of features such as the study setting, methodology used to derive the values, baseline scores, and severity of the disease.(63) Change over time was also presented by the effect sizes. The effect size provided another perspective to measuring recovery after total joint arthroplasty in which comparison across measures can be made. Regardless of the type of outcome measure, large effect sizes are seen with total joint arthroplasty both over short-term and long-term outcomes. Because a number of HRQL measures are used to evaluate the outcomes after total joint arthroplasties, comparisons can be challenging. This review summarized published findings to help place the magnitude of change seen with total joint arthroplasty in perspective. Changes seen with HRQL are one aspect of evaluating outcomes from a patient perspective; however, recovery is a complex concept(64) that needs many clinical and research-oriented measures to evaluate the full spectrum of recovery.

Is surgery for cervical spondylotic myelopathy cost-effective? A cost-utility analysis based on data from the AOSpine North America prospective CSM study

Object

Surgical intervention for appropriately selected patients with cervical spondylotic myelopathy (CSM) has demonstrated favorable outcomes. This study evaluates the cost-effectiveness of this type of surgery in terms of cost per quality-adjusted life year (QALY) gained.

Methods

As part of a larger prospective multicenter study, the direct costs of medical treatment for 70 patients undergoing surgery for CSM at a single institution in Canada were retrospectively obtained from the hospital expenses database and physician reimbursement data. Utilities were estimated on the entire sample of 278 subjects enrolled in the multicenter study using SF-6D–derived utilities from 12- and 24-month SF-36v2 follow-up information. Costs were analyzed from the payer perspective. A 10-year horizon with 3% discounting was applied to health-utilities estimates. Sensitivity analysis was performed by varying utility gain by 20%.

Results

The SF-6D utility gain was 0.0734 (95% CI 0.0557–0.0912, p < 0.01) at 12 months and remained unchanged at 24 months. The 10-year discounted QALY gain was 0.64. Direct costs of medical treatment were estimated at an average of CaD $21,066. The estimated cost-utility ratio was CaD $32,916 per QALY gained. The sensitivity analysis showed a range of CaD $27,326–$40,988 per QALY gained. These estimates are within the limits for medical procedures that have an acceptable cost-utility ratio.

Conclusions

Surgical treatment for CSM is associated with significant improvement in health utilities as measured by the SF-6D. The direct cost of medical treatment per QALY gained places this form of treatment within the category deemed by payers to be cost-effective.

[Primary hip replacement: first year results and predictive factors of poor outcome]

OBJECTIVE

To evaluate the results of total hip arthroplasty in patients with osteoarthritis and to identify predictors of poor functional outcome.

MATERIAL AND METHODS

A prospective observational study in patients operated on in 2006 with total hip arthroplasty in 4 hospitals in Guipúzcoa, followed up for 1 year.

OUTCOME VARIABLES

pain, physical function, complications, mortality, quality of life by WOMAC and SF-12 (at 0, 3, 6 and 12 months) and «Poor functional outcome» at one year (last quartile of the WOMAC in function area). Logistic regression was performed to examine predictors of poor functional outcome.

RESULTS

A total of 166 patients were followed up. The incidence of systemic and local complications was 6.3% and 14.5%, respectively, 4.3% readmissions and no deaths related to surgery. Close to 40 points improvement in pain, stiffness and WOMAC functional limitation, mainly in the first 3 months after surgery. A similar trend was seen, but lower in the physical and mental component of the SF12 (12 and 8 points, respectively). The previous score on the WOMAC function area and the physical component of SF-12, and the existence of any complications, are predictors of poor functional recovery.

DISCUSSION

The improvement experienced after the surgery is already very important before the third month. The functional and physical status before surgery and possible complications of surgery are significant determinants of the results.