The learning curve for the direct anterior approach for total hip arthroplasty: a single surgeon's first 500 cases

Comparison of Anterior and Posterior Surgical Approaches in Total Hip Arthroplasty: Effect on Self-Reported and Functional Outcomes

Background/Objectives: Reported patient results after total hip arthroplasty (THA) have been described as a function of surgical approach. Such results have commonly been subjective. Though self-reported outcomes are of value and often utilized, inclusion of functional performance measures represents an objective measure to compare THA techniques. Methods: Patients that underwent primary THA surgery at our institution were grouped by surgical approach (Direct Anterior vs Posterior). Patient data were collected pre-operatively, as well as post-operatively at three and twelve months. Hip Dysfunction and Osteoarthritis Outcome Score (HOOS JR) was utilized, and function was assessed with the timed up and go test (TUGT), 4-m walk test (4MWT), and 30 s sit-to-stand (30STS) test. Unpaired T tests were used to compare mean results and differences between the groups. Results: Functional outcome scores were improved to a similar degree for both surgical approach groups at all the time points post-operatively. At 3 months, the TUGT was improved by 2.33 s for the posterior group, the 30STS was increased by 2.71 repetitions, and the 4MWT was increased by 1.23 s; the anterior group had 2.66 s, 2.49 repetition, and 1.18 s improvements in the three functional tests, respectively. At 12 months, the posterior group had improvements of 2.86 s, 3.99 repetition, and 1.19 s, while the anterior group had improvements of 3.15 s, 3.83 repetition, and 1.23 s, respectively. No clinical and statistical significant differences in surgical approach were noted in these measures. In contrast, the anterior group showed a statistically significant but not clinically significant improvement in self-reported HOOS JR scores compared to the posterior group at the 3-month post-operative mark (p = 0.045). Conclusions: This study suggests both anterior and posterior surgical approaches to total hip arthroplasty yield equivalent functional results at 3 months and one year post-operatively, while the anterior approach demonstrates more improved patient satisfaction than the posterior approach at the 3-month post-operative assessment.

Outcomes Following Direct Anterior Approach Total Hip Arthroplasty: A Contemporary Multicenter Study

BACKGROUND

The direct anterior approach (DAA) is a popular approach for primary total hip arthroplasty (THA). However, the contemporary outcomes for DAA THA need further elucidation. Therefore, we aimed to describe implant survivorship, complications, and clinical outcomes after DAA THA.

METHODS

From our multi-institutional total joint registry, 3,184 patients who had undergone 3,698 primary DAA THA between 2010 and 2019 were identified. The identified patients had a mean age of 65 years and a mean body mass index (BMI) of 29 kg/m 2 , and 53% of patients were female. The indications for revision and reoperation and the incidence of complications were collected and analyzed. Potential risk factors, including age, sex, BMI, and high-volume compared with low-volume operating surgeons, were examined. Descriptive statistics and Kaplan-Meier survivorship with Cox regression analyses were performed.

RESULTS

At 10 years following primary DAA THA, the cohort had 96% (95% confidence interval [CI], 95% to 98%) survivorship free of any revision and 94% (95% CI, 92% to 96%) survivorship free of any reoperation. The leading indications for revision were periprosthetic joint infection (PJI) (n = 24; 5-year cumulative incidence, 0.93% [95% CI, 0.6% to 1.5%]), periprosthetic fracture (n = 20; 5-year cumulative incidence, 0.62% [95% CI, 0.4% to 1.0%]), and aseptic loosening (n = 14; 11 femoral, 3 acetabular; 5-year cumulative incidence, 0.84% [95% CI, 0.5% to 1.5%]). A BMI of ≥40 kg/m 2 was found to be significantly associated with PJI (hazard ratio [HR], 6.4; p < 0.001), reoperation (HR, 3.5; p < 0.001), and nonoperative complications (HR, 2.3; p = 0.018). Survivorship free of recurrent instability was 99.6% (95% CI, 99.4% to 99.8%) at 5 and 10 years, and the cumulative incidence of revision for instability was 0.14% at 5 years.

CONCLUSIONS

In one of the largest published series to date, survivorship following DAA THA was satisfactory at early to intermediate follow-up. The leading indications for revision were PJI, periprosthetic fracture, and aseptic loosening. Instability after DAA THA was uncommon and infrequently led to revision. As a note of caution, a BMI of ≥40 kg/m 2 was identified as a risk factor for adverse outcome after DAA THA.

LEVEL OF EVIDENCE

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

Learning curve comparison between switching approach and switching implant in cementless short stem total hip arthroplasty

INTRODUCTION

Implementing new approaches or new implants is always related with a certain learning curve in total hip arthroplasty (THA). Currently, many surgeons are switching to minimally invasive approaches combined with short stems for performing THA. Therefore, we aimed to asses and compare the learning curve of switching from an anterolateral Watson Jones approach (ALA) to a direct anterior approach (DAA) with the learning curve of switching from a neck-resecting to a partially neck-sparing short stem in cementless THA.

MATERIALS AND METHODS

The first 150 consecutive THA performed through a DAA (Group A) and the first 150 consecutive THA using a partially neck-sparing short stem (Group B) performed by a single surgeon were evaluated within this retrospective cohort study. All cases were screened for surgery related adverse events (AE). Furthermore, the operative time of each surgery was evaluated and the learning curve assessed performing a cumulative sum (CUSUM) analysis.

RESULTS

Overall, significantly more AE occurred in Group A compared to Group B (18.0% vs. 10.0%; p = 0.046). The sub-analysis of the AE revealed higher rates of periprosthetic joint infections (2.7% vs. 0.7%; p = 0.176), periprosthetic fractures (4.0% vs. 2.0%; p = 0.310) and overall revisions (4.7% vs. 1.3% p = 0.091) within Group A without statistical significance. The CUSUM analysis revealed a consistent reduction of operative time after 97 cases in Group A and 79 cases in Group B.

CONCLUSION

A significantly higher overall rate of AE was detected while switching approach compared to switching implant for performing THA. However, according to the results of this study, surgeons should be aware of the learning curve of the adoption to a new implant with different fixation philosophy as well.

Incidence of heterotopic ossification following total hip arthroplasty by approach: a systematic review

BACKGROUND

Heterotopic ossification (HO) formation has been increasingly recognized as a complication of major orthopedic surgeries, particularly total hip arthroplasty (THA). Though, the overall incidence of HO following THA has been well-documented, it is often not reported by severity or by surgical approach.

QUESTIONS/PURPOSES

(1) What are the demographics of patients with HO? (2) What is the severity of HO following THA using the Brooker classification? (3) What is the incidence and class of HO following different THA approaches (anterior, posterior, posterolateral, anterolateral, superior, lateral, trans-gluteal)? (4) What are the number and training level of surgeons who performed each procedure?

METHODS

The PubMed, Embase, and Web of Science databases were queried, and PRISMA guidelines were followed. Qualitative and quantitative analyses were performed using Microsoft Excel.

RESULTS

We isolated 26 studies evaluating 6512 total hip arthroplasties (THA). The mean HO percentage overall was 28.8%, mostly Class I (54.2%) or Class II (29.6%). The highest percentage of HO was associated with the modified direct lateral (57.2%) and the traditional lateral (34.6%) approaches. The lowest HO percentages were identified following posterolateral (12.8%) and direct superior approaches (1%). Most studies reported a singular senior surgeon operating within the same approach for all patients.

CONCLUSIONS

The traditional lateral and modified direct lateral approaches to THA resulted in the highest percentage of HO postoperatively. However, most ossification cases were not clinically significant and did not strongly affect overall patient morbidity. Further studies are warranted to identify an association between severity of ossification and different arthroplasty approaches.

First 100 total hip arthroplasties performed by a young surgeon using the direct anterior approach: learning curve and complications

INTRODUCTION

Most of the reported discussions about the learning curve for the direct anterior approach (DAA) in total hip arthroplasty (THA) have been by experienced surgeons. The study's aim was to describe the learning curve, short-term outcomes, complications, and adaptations to the DAA used in the first 100 THA cases experienced by a young surgeon who had received DAA training for trauma surgeries.

MATERIALS AND METHODS

This retrospective study summarizes the first 100 consecutive cases experienced by a young surgeon who performed the unilateral DAA for THA between 2019 and 2021. Cumulative sum (CUSUM) analysis was performed to evaluate the learning curve on the basis of operative time and overall complications. The demographics data, short-term outcomes, and complications of the first 50 and second 50 cases were compared.

RESULTS

The CUSUM curve declined after 49 and 55 cases, measured by operative time and overall complications, respectively. The median operative time (104 vs. 80 min) and intraoperative fluoroscopic time (38 vs. 12 s) increased significantly in the first 50 cases compared with the times in the second 50 cases. Complications tended to occur in the first 50 cases (12% vs. 6%), and the overall rate was 9%. Major complications all occurred in the first 50 cases, with a rate of 4%. Only one case, which involved a complicated periprosthetic fracture around the stem that extended to the tip, required the intervention of a senior surgeon.

CONCLUSIONS

Even after receiving training on the DAA for trauma surgeries, the young surgeon experienced a steep learning curve and more complications in the first 50 cases. The DAA for THA is a technically demanding procedure and may require guidance from an experienced surgeon to manage unexpected complications.

Periprosthetic fracture following anterior approach or dislocation after posterior approach: which one is the lesser evil?

INTRODUCTION

The most common approaches in total hip arthroplasty (THA) have different complication profiles; anterior-approach (AA-THA) has an increased risk of periprosthetic fractures (PPF); posterior-approach (PA-THA) is associated with higher dislocation risk. However, the relative severity of one versus the other is unknown. This study aims to compare outcome of patients who suffered PPF after AA-THA with those that sustained dislocation after PA-THA.

METHODS

This is a retrospective, single-center, multi-surgeon, consecutive case-series of primary THA patients. In a cohort of 9867 patients who underwent THA, 79 fulfilled the approach-specific, post-operative complication criteria, of which 44 were PPF after AA-THA and 35 with dislocation after PA-THA (age 67.9 years (range: 38.0-88.1), 58.2% women). Outcome included complication- and revision- rates, and patient-reported outcomes including Oxford Hip Score (OHS).

RESULTS

At 5.8 years follow-up (range: 2.0-18.5), reoperation was more common in the dislocation after PA-THA group (23/35 vs. 20/44; p = 0.072). Change of surgical approach occurred in 15/20 of patients with PPF after AA-THA, but none in those with dislocation after PA-THA. Following re-operation, complication rate was greater in the PPF group (9/20 vs. 4/23; p = 0.049). At latest follow-up, OHS were superior in the PPF after AA-THA group [42.6 (range: 25.0-48.0) vs. 36.6 (range: 21.0-47.0); p = 0.006].

CONCLUSION

Dislocation following PA-THA is more likely to require revision. However, PPF following AA-THA requires more often a different surgical approach and is at higher risk of complications. Despite the increased surgical burden post-operative PROMs are better in the peri-prosthetic fracture group, especially in cases not requiring reoperation.

LEVEL OF EVIDENCE

III, case-control study.

Early Practice All-Cause Complications for Fellowship-Trained Anterior Hip Surgeons Are Not Increased When Compared to "Gold Standard" Experienced Posterior Approach Surgeons

BACKGROUND

Increased complication rates have been reported during the learning curve for direct anterior approach (DAA) total hip arthroplasty (THA). However, emerging literature suggests that complications associated with the learning curve may be substantially reduced with fellowship training.

METHODS

Our institutional database was queried to identify 2 groups: (1) 600 THAs comprised of the first 300 consecutive cases performed by 2 DAA fellowship-trained surgeons; and (2) 600 posterolateral approach (PA) THAs, including the most recent 300 primary cases performed by 2 experienced PA surgeons. All-cause complications, revision rates, reoperations, operative times, and transfusion rates were evaluated.

RESULTS

Comparing DAA and PA cases, there were no significant differences in rates of all-cause complications (DAA = 18, 3.0% versus PA = 23, 3.8%; P = .43), periprosthetic fractures (DAA = 5, 0.8% versus PA = 10, 1.7%; P = .19), wound complications (DAA = 7, 1.2% versus PA = 2, 0.3%; P = .09), dislocations (DAA = 2, 0.3% versus PA = 8, 1.3%, P = .06), or revisions (DAA = 2, 0.3% versus PL = 5, 0.8%; P = .45) at 120 days postoperatively. There were 4 patients who required reoperation for wound complications, all within the DAA group (DAA = 4, 0.67% versus PA = 0; P = .045). Operative times were shorter in the DAA group (DAA <1.5 hours = 93% versus PA <1.5 hours = 86%; P < .01). No blood transfusions were given in either group.

CONCLUSION

In this retrospective study, DAA THAs performed by fellowship-trained surgeons early in practice were not associated with higher complication rates compared to THAs performed by experienced PA surgeons. These results suggest that fellowship training may allow DAA surgeons to complete their learning curve period with complication rates similar to experienced PA surgeons.

Selective THA-approach use amongst junior surgeons improves safety of introducing the anterior approach: a prospective, multi-surgeon, comparative, study

BACKGROUND

Learning curves associated with independent practice and anterior approach total hip arthroplasty (AA-THA) has been associated with inferior outcome. This study compared outcome of junior, fellowship-trained, surgeons who perform THA through both anterior and posterior (PA) approach, with senior surgeons who perform either AA or PA, to determine whether: 1. Fellowship training and selective practice allows for safe introduction of AA into practice; and 2. Whether selective approach-use influences outcome.

METHODS

This is a prospective, consecutive study comparing the first 800 THAs of two junior, dual-approach, surgeons (AA/PA: 455/345), with 400 THAs cases of two senior, single-approach, surgeons (AA/PA: 200/200), between 2018 and 2020. Most patients were female (54.4%), mean age was 65 years-old (range 19-96) and mean BMI was 29 kg/m2 (range 16-66). Outcome included radiologic measurements (inclination/anteversion and leg-length), complication- and revision rates, and patient-reported outcomes including Oxford Hip Score (OHS).

RESULTS

At 3.1 years (range 2.0-6.8) follow-up, there were 43 complications (3.6%), including 27 re-operations (2.3%); with no difference between junior and senior surgeons for AA-THA (Junior: 8/455 vs. Senior: 3/200; p = 0.355) or PA-THA (Junior: 11/345 vs. Senior: 5/200; p = 0.400). Amongst juniors, there was no difference in complications (AA:8/455 vs. PA:11/345; p = 0.140) and in ΔOHS (AA:20.5 ± 7.7 vs. PA:20.5 ± 8.0; p = 0.581) between approaches.

CONCLUSION

Contemporary training and selective approach-use minimizes the learning curve, allowing junior staff to have equivalent outcome to established, senior surgeons in both AA and PA. We would advocate for selective approach use amongst junior arthroplasty surgeons when introducing the AA into independent practice.

Comparing direct anterior approach versus posterior approach or lateral approach in total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

There are several approaches to THA, and each has their respective advantages and disadvantages. Previous meta-analysis included non-randomised studies that introduce further heterogeneity and bias to the evidence presented. This meta-analysis aims to present level I evidence by comparing functional outcomes, peri-operative parameters and complications of direct anterior approach (DAA) versus posterior approach (PA) or lateral approach (LA) in THA.

PATIENTS AND METHODS

A comprehensive multi-database search (PubMed, OVID Medline, EMBASE) was conducted from date of database inception to 1st December 2020. Data from randomised controlled trials comparing outcomes of DAA versus PA or LA in THA were extracted and analysed.

RESULTS

Twenty-four studies comprising 2010 patients were included in this meta-analysis. DAA has a longer operative time (MD = 17.38 min, 95%CI: 12.28, 22.47 min, P < 0.001) but a shorter length of stay compared to PA (MD = - 0.33 days, 95%CI: - 0.55, - 0.11 days, P = 0.003). There was no difference in operative time or length of stay when comparing DAA versus LA. DAA also had significantly better HHS than PA at 6 weeks (MD = 8.00, 95%CI: 5.85, 10.15, P < 0.001) and LA at 12 weeks (MD = 2.23, 95%CI: 0.31, 4.15, P = 0.02). There was no significant difference in risk of neurapraxia for DAA versus LA or in risk of dislocations, periprosthetic fractures or VTE between DAA and PA or DAA and LA.

CONCLUSION

The DAA has better early functional outcomes with shorter mean length of stay but was associated with a longer operative time than PA. There was no difference in risk of dislocations, neurapraxias, periprosthetic fractures or VTE between approaches. Based on our results, choice of THA approach should ultimately be guided by surgeon experience, surgeon preference and patient factors.

LEVEL OF EVIDENCE I

Meta-analysis of randomised controlled trials.

Radiographic parameters of pelvic and proximal femoral morphology do not predict outcomes for direct anterior total hip arthroplasty

BACKGROUND

Radiographic predictors of outcomes associated with direct anterior approach (DAA) total hip arthroplasty (THA) are largely unknown. Anecdotally, some surgeons limit surgery to patients with low body mass index (BMI) or "favorable" bony morphology. Objective data on the impact of these factors is limited. We sought to determine radiographic and demographic predictors of outcomes after DAA arthroplasty.

METHODS

A consecutive series of patients undergoing unilateral, elective DAA THA, who had linked pre- and post-operative patient reported outcome scores, from January 1, 2017 to March 30, 2019 were included. Radiographic measurements, including proxies for pelvic overhang, femoral canal access, acetabular morphologic changes, and markers of disease severity, were performed on calibrated radiographs. Intra-observer consistency was also evaluated. Outcome measures included disease specific and general health patient-reported outcomes scores, while surgical difficulty was approximated by estimated blood loss and surgical time. Multivariate analyses were performed to determine statistically significant correlations.

RESULTS

168 patients were included. Overall, patients experienced significant improvement in outcome scores (mean ∆ HOOS-JR 39.4, PROMIS-physical 12.3). There were two reoperations (1.2%), for recurrent dislocation. Female sex (p = 0.015) and increasing age (p == 0.019) were associated with shorter surgical times. No statistically significant correlations were found between the radiographic parameters and outcome measures. Intraclass correlation coefficients of the radiographic measurements were overall strong (0.73-1.0).

CONCLUSION

We demonstrated consistent results in this series of patients despite variation in bony morphology. Our findings suggest that DAA THA can be safely performed on a broader patient population.

Accuracy of digital templating in uncemented primary total hip arthroplasty: which factors are associated with accuracy of preoperative planning?

BACKGROUND

Preoperative planning is a fundamental step for successful total hip arthroplasty (THA). Studies have highlighted the accuracy of preoperative digital templating for estimating acetabular cup and stem size. Stem design such as single-wedge metadiaphyseal (Type 1 stem) versus mid-short stem (microplasty) and surgical approach (anterior, direct lateral or posterior) have not been well investigated as predictors of THA templating accuracy.

METHODS

204 patients (220 hips) who had undergone elective THA between November 2016 and December 2019 and presented a saved preoperative template were retrospectively reviewed. Templates from 5 different surgeons were involved in the analysis. 3 different approaches were used: direct lateral (DL), posterior (PA), direct anterior (DAA). 2 different stem designs were used: single-wedge metadiaphyseal and single-wedge mid-short (Biomet Taperloc Microplasty), while the acetabular component remained the same. Bivariate and multivariate regression analyses were performed to determine predictors of accuracy.

RESULTS

Femoral component size templating accuracy was significantly improved when using the single-wedge mid-short stem (Taperloc Microplasty) design when performing bivariate analysis. Although accuracy of cup sizing was not affected by approach, precision was significantly better in the PA group (p < 0.05). Accuracy of templating was found to be independent of BMI and gender but dependent on presence of calibration marker and stem design (p < 0.05).

CONCLUSIONS

When striving for improved templating accuracy, acetabular and femoral component accuracy were best achieved using a calibration marker and a metaphyseal short femoral stem design.

Penalty for Switching Implants? Assessing the Learning Curve With a Collarless, Tapered Wedge Cementless Femoral Component

Background

Surgeon learning curve associated with a tapered wedge femoral implant as measured by early femoral component subsidence and 90-day risk of reoperation was evaluated.

Methods

The first 451 patients undergoing primary, cementless total hip arthroplasty by a single, fellowship-trained arthroplasty surgeon with a tapered wedge stem design were retrospectively reviewed. Early radiographic femoral component subsidence during the first 6 weeks postoperatively and 90-day reoperations was recorded.

Results

When stratified by approach, there was no association between date of surgery and femoral component subsidence in the posterior approach (P-value for linear trend over time = 0.44). In the direct anterior approach, there was a significant association between date of surgery and early femoral component subsidence (P-value for linear trend over time = 0.01). For both approaches, there was an increase in implanted stem size relative to templated stem size over time (P < .01 and P = .03, respectively). There was no association between the date of surgery and risk of 90-day reoperation (P = .45).

Conclusions

In a single surgeon's initial use of a tapered cementless wedge stem, early femoral component subsidence was not impacted by the surgeon's learning curve when the posterior approach was utilized. Although subsidence was associated with date of surgery in the direct anterior cohort, this was not associated with increased risk of 90-day reoperation. Should a surgeon adopt a new tapered-wedge stem, these findings suggest that the stem is forgiving both in relation to subsidence and 90-day reoperation risk when appropriate surgical technique is utilized.

Direct anterior versus direct lateral hip approach in total hip arthroplasty with the same perioperative protocols one year post fellowship training

BACKGROUND

Variable results have been reported regarding the clinical outcomes in Total hip arthroplasty (THA) based on the surgical approach. The aim of this study is to compare the clinical outcomes between Direct anterior (DA) and direct lateral (DL) approaches in THA when performed immediately after fellowship training.

METHODS

During the 1st year of practice, all consecutive patients who underwent THA via DA and DL hip approaches were retrospectively investigated. Patients'demographics, diagnosis, American society of Anesthesiology (ASA) score, route of anesthesia, length of hospital stay (LOS), leg length discrepancy (LLD), radiographic parameters, operative time, number of opioids refills postoperatively, and complications were collected and compared between the two groups. The short form of Hip Disability and Osteoarthritis Outcome score, Joint Replacement (HOOS, JR) was prospectively collected pre and postoperatively. The minimum follow-up period was 2 years.

RESULTS

Forty patients in DA group and 38 patients in DL group were included. No statistically significant difference was found between the two groups in terms of demographics, diagnosis, ASA scores, route of anesthesia at the time of THA, postoperative radiographic parameters, LOS, LLD, opioid refills and HOOS scores (p > 0.05). Patients in the DA group had shorter operative time (83 ± 17 min) when compared to the DL group (93 ± 24 min) (p = 0.03). No major complications were found except for one early deep infection patient in DL group.

CONCLUSION

Both DA and DL approaches resulted in satisfactory outcomes in THA when performed by a fellowship trained surgeon.

Risk factor analysis on perioperative greater trochanteric fracture of total hip arthroplasty via anterolateral approach

INTRODUCTION

A greater trochanteric fracture is a perioperative complication of primary total hip arthroplasty (THA) via an anterolateral approach. Although surgeons determine risk factors in the preoperative planning phase, no study explored the relationship between the planned femoral implant and greater trochanter. This study attempts to determine the risk factors for perioperative greater trochanteric fractures in primary THA via an anterolateral approach.

MATERIALS AND METHODS

This retrospective single-institution study enrolled 440 patients (66 males and 374 females) who underwent primary THA via an anterolateral approach with a minimum follow-up of six months. First, we selected patients with perioperative greater trochanteric fractures, regardless of the need for additional surgery. Second, we investigated the risk factors for perioperative greater trochanteric fractures using the patients' demographic data, operative data, and femoral geometry data via univariate and multivariate analyses.

RESULTS

Perioperative greater trochanteric fractures occurred in 30 joints (30/440, 6.8%), and all cases were reported in women. Multivariate analysis revealed that in cases where the top of the great trochanter was inside the longitudinal central axis of the planned femoral stem in three-dimensional templating (Type B) was the only independent risk factor for perioperative greater trochanteric fracture (odds ratio, 14.6; 95% confidence interval, 5.88-36.1; P < 0.001).

CONCLUSION

This study identified female sex and Type B femoral geometry as risk factors for perioperative greater trochanteric fracture via an anterolateral approach. Our results may reduce the incidence of perioperative greater trochanteric fractures associated with primary THA.

Heterotopic ossification after total hip arthroplasty: radiological comparison between a direct anterior approach without an orthopaedic table and a posterior approach

INTRODUCTION

Heterotopic ossification (HO) occurs in almost ⅓ of total hip arthroplasties (THAs). A direct anterior approach (DAA) with an orthopaedic table is less likely to cause HO than a posterior approach. Without an orthopaedic table, the exposure of the femur requires additional soft tissue release. Soft tissue trauma leads to the production of HO inductors. Our study evaluated the incidence of HO 6 months after THA and compared the results between DAAs without an orthopaedic table and posterior approaches.

METHODS

Retrospectively, 164 consecutive, primary THAs were included: 76 through a posterior approach and 88 through a DAA. The main objective was to measure the presence of HO on pelvis radiography 6 months after surgery.

RESULTS

The incidence of HO was significantly higher in the DAA group than in the posterior approach group (47.7% vs. 27.6%, respectively; p < 0.01). The overall incidence of HO was 38.4%. No significant difference was found between the 2 approaches regarding the severity of HO. No significant risk factor for HO was identified other than the surgical approach.

DISCUSSION

In our study, the incidence of HO after THA in patients undergoing DAA without an orthopaedic table was higher than in patients undergoing a posterior approach after 6 months of follow-up. This result is closely related to the surgical trauma. It suggests that the minimally invasive feature of a surgical approach cannot be dissociated from the overall conditions in which it is performed.

Direct Anterior Approach in Hip Hemiarthroplasty for Femoral Neck Fractures: Do Short-Term Outcomes Differ with Approach?: A Systematic Review and Meta-Analysis

BACKGROUND

Hip hemiarthroplasty (HA) is commonly used to treat femoral neck fractures, but it remains unclear if the surgical approach impacts patient outcomes for this commonly performed procedure. The objective of this systematic review and meta-analysis was to assess early postoperative outcomes in patients undergoing HA for femoral neck fracture with the direct anterior approach (DAA) compared with other approaches.

METHODS

The Cochrane Central Registry of Controlled Trials, MEDLINE, and Google Scholar databases were searched for randomized controlled trials, prospective nonrandomized trials, and retrospective studies published prior to September 7, 2021, comparing DAA with other approaches (anterolateral approach [ALA], direct lateral approach [DLA], and posterior-based approach [PA]) in HA for femoral neck fractures. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Outcomes included functional outcomes, total complications, prosthetic dislocation, periprosthetic fracture, periprosthetic joint infection (PJI), reoperation, mortality, pain, operative time, and perioperative blood loss. Fixed effect odds ratios, along with their 95% confidence intervals, were used to analyze dichotomous variables. Significance was set at p < 0.05. Meta-analysis was conducted with Review Manager 5.4.

RESULTS

In total, 19 studies were included for qualitative analysis and 16 studies were included for quantitative analysis, with a total of 1,604 cases analyzed (723 DAA, 215 ALA, 301 DLA, and 365 PA). Compared with other approaches, the use of the DAA for HA was associated with improved early postoperative functional outcomes, lower early postoperative pain scores, fewer total complications, and fewer prosthetic hip dislocations. The rates of periprosthetic fracture, PJI, and reoperation, pain scores beyond 40 days, operative time, perioperative blood loss, and mortality were not significantly different between surgical approaches.

CONCLUSIONS

Utilizing the DAA while performing HA for femoral neck fractures is associated with improved functional outcomes, lower early postoperative pain scores, lower incidence of prosthetic hip dislocation, and potentially fewer total complications.

LEVEL OF EVIDENCE

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

Patients are Most Interested in Which Hip Arthroplasty Approach? A 15-year Google Trends Analysis

Background

Methods

Results

Conclusions

Learning curve for active robotic total knee arthroplasty

PURPOSE

Total Knee Arthroplasty (TKA) procedures incorporate technology in an attempt to improve outcomes. The Active Robot (ARo) performs a TKA with automated resections of the tibia and femur in efforts to optimize bone cuts. Evaluating the Learning Curve (LC) is essential with a novel tool. The purpose of this study was to assess the associated LC of ARo for TKA.

METHODS

A multi-center prospective FDA cohort study was conducted from 2017 to 2018 including 115 patients that underwent ARo. Surgical time of the ARo was defined as Operative time (OT), segmented as surgeon-dependent time (patient preparation and registration) and surgeon-independent time (autonomous bone resection by the ARo). An average LC for all surgeons was computed. Complication rates and patient-reported outcome (PRO) scores were recorded and examined to evaluate for any LC trends in these patient related factors.

RESULTS

The OT for the cases 10-12 were significantly quicker than the OT time of cases 1-3 (p < 0.028), at 36.5 ± 7.4 down from 49.1 ± 17 min. CUSUM and confidence interval analysis of the surgeon-dependent time showed different LCs for each surgeon, ranging from 12 to 19 cases. There was no difference in device related complications or PRO scores over the study timeframe.

CONCLUSION

Active Robotic total knee arthroplasty is associated with a short learning curve of 10-20 cases. The learning curve was associated with the surgical time dedicated to the robotic specific portion of the case. There was no learning curve-associated device-related complications, three-dimensional component position, or patient-reported outcome scores.

LEVEL OF EVIDENCE

Level II.

Postoperative acetabular component position in revision hip arthroplasty: a comparison of the anterior and posterior approaches

BACKGROUND

While previously considered unsuitable for revision total hip arthroplasty (rTHA), the direct anterior approach (DAA) can be extended to allow for safe acetabular component revision. In primary hip arthroplasty, the DAA and its associated fluoroscopy, has been shown to produce more acceptable component positioning. However, there is little data comparing the DAA to the posterior approach (PA) for rTHA. We hypothesised that, the DAA with intraoperative fluoroscopy would allow for more precise acetabular component positioning when compared to those performed using a PA.

METHODS

50 consecutive patients (25 DAA and 25 PA) undergoing rTHA were included. Radiographic analysis of postoperative acetabular component position was then performed. Univariate and multivariate analyses was performed to assess the contribution of approach on cup positioning inside classically defined "safe zones".

RESULTS

Baseline patient characteristics were similar. The PA was associated with more cups placed outside the Lewinnek (48% vs. 12%, p = 0.005) and the Danoff (52% vs. 28%, p = 0.083) "safe zones" when compared to the DAA. Multivariate analysis revealed that operative approach was the only patient or surgical factor associated with component position outside of the "safe zones" (Lewinnek [OR = 13.6; 95% CI, 2.12-87.9, p = 0.006] and Danoff [OR = 7.7; 95% CI, 1.48-40.1, p = 0.015]).

CONCLUSION

Our results suggest that the DAA allows for more reproducible and precise cup placement in RTHA. The safe-zone paradigm remains a useful index of accurate cup positioning and the DAA, with use of intraoperative fluoroscopy, offers more consistent acetabular component positioning when compared to the PA.

Anterior-Based Approaches to Total Hip Arthroplasty: Beyond the Learning Curve

BACKGROUND

Anterior-based approaches for total hip arthroplasty (THA) have gained popularity over the last decade. At our institution, anterior-based approaches are preferentially utilized, including both anterior-based muscle-sparing (ABMS) and direct anterior (DA) for primary THA. As there are higher complication rates during the transition to an anterior approach, we compared the outcomes and complications between ABMS and DA approaches beyond the learning curve.

METHODS

A retrospective study of all ABMS and DA primary THA patients performed at a single institution was performed, excluding the first 100 anterior cases done by any surgeon. In total, 813 DA and 378 ABMS THA cases were included. Demographics, complications, and patient-reported outcomes (PROMIS and HOOS) were obtained for each patient.

RESULTS

There was a 4.5% overall complication rate (4.1% in DA and 5.6% in ABMS, P = .248), with the most common complication being infection at 1.7% (1.5% vs 2.1%, P = .423). A revision was performed in 3.4% of cases overall (1.8% aseptic, 1.6% septic). There was no difference in complication rates between approaches. Length of surgery was shorter for ABMS (94.5 vs 116.0 minutes, P < .001). Both DA and ABMS had significant improvements in PROMIS and HOOS Jr. scores, without any significant difference between the groups.

CONCLUSIONS

Anterior-based approaches for primary THA demonstrated excellent clinical results and low complication rates overall. Beyond the learning curve, excellent results can be obtained with either ABMS or DA approach for primary THA.

The Supercapsular Percutaneously Assisted Total Hip (SuperPATH) Approach Revisited: Technique Improvements after the Perioperative Experience of 344 Cases

The SuperPATH approach is a direct superior portal-assisted approach for total hip arthroplasty (THA) that utilizes the interval between the gluteus minimus and the piriformis to access the hip capsule. Patients and Methods: SuperPATH arthroplasty was performed by a single surgeon between December of 2016 and December of 2021 in 344 cases. The technique described by Chow was performed in all cases. The average length of stay was 1.3 days, and all patients were discharged for home. All patients were mobilized on the day of the operation. Six cases presented complications: four intraoperative femur fractures and two peroneal nerve palsies. No infection and no hip dislocation were noticed in any case. Modifications: We recommend that the patient be placed as far from the surgeon as possible as well as the use of a sterilized standard linen pack to elevate the foot and internally rotate the hip. In addition, regarding instrumentation, we recommend the use of a 4.5 mm drill for the first guidance femur drilling and a standard corkscrew for femoral head removal. Finally, we propose a different reduction technique using a hook. The use of the SuperPATH approach allows for maximal tissue sparing through preservation of external rotators and minimizing stretching of the gluteus medius. There is no range of motion restrictions postoperatively and patients can achieve a high level of function with a very low dislocation risk and reduced inpatient stay. Furthermore, an incision extension is possible if needed in complex cases. For surgeons familiar with the standard posterolateral approach, the SuperPATH approach is a reliable and safe method with promising results for the patient. In order to improve the surgical effect and facilitate some steps in the procedure, we share our experience and recommend some modifications.

Reduced Incidence of Perioperative Periprosthetic Fractures Using Hybrid Rasp-Impaction Broaching Over Impaction Broaching When Using the Direct Anterior Approach for Total Hip Arthroplasty

Background

A not infrequent complication encountered with the direct anterior approach is perioperative fracture. The purpose of this study was to compare the incidence of perioperative fractures using a hybrid rasp-impaction broach vs an impaction broach for a similarly designed stem.

Methods

Retrospective study of 798 primary total hip replacements by 1 surgeon performed using noncollared dual tapered femoral stems, including 457 implanted using hybrid rasp-impaction broaching and 341 implanted using impaction broaching. Intraoperative and 90-day postoperative fractures were identified in each group. Bivariate tests and multivariate regression analysis were used to compare the 2 groups.

Results

There were 33 (4.1%) fractures in the sample, 13 (2.8%) with hybrid rasp-impaction broaching and 20 (5.8%) with impaction broaching (P = .034). Three (0.7%) intraoperative fractures occurred with hybrid rasp-impaction broaching and 12 (3.5%) with impaction broaching (P = .003). Five (1.1%) total calcar fractures occurred with hybrid rasp-impaction broaching and 11 (3.2%) with impaction broaching (P = .034). Intraoperative calcar fractures occurred with 1 (0.2%) hybrid rasp-impaction broaching and 6 (1.8%) impaction broaching (P = .021). In multivariate analyses, hybrid rasp-impaction broaching had a statistically lower odds ratio (OR) for total fracture (OR 0.45 [0.22 to 0.93]); total intraoperative fracture (OR 0.17 [0.05 to 0.60]); total calcar fracture (OR 0.33 [0.11 to 0.97]); intraoperative calcar fracture (OR 0.11 [0.01 to 0.98]); and rate of readmission (OR 0.27 [0.10 to 0.78]).

Conclusion

The use of a hybrid rasp-impaction broach compared with impaction broach led to a reduced incidence of periprosthetic fractures when using a dual tapered stem through the direct anterior approach.

A comparative of a single novice surgeon's direct anterior approach and posterior approach learning curves in total hip arthroplasty: a retrospective cohort study

INTRODUCTION

The purpose of the present study was to compare a novice surgeon's learning curves with the direct anterior approach and posterior approach in total hip arthroplasty.

METHODS

A consecutive series of 376 total hip arthroplasties performed from November 2014 to September 2019 in a level-one healthcare center by a single surgeon (V.B) were retrospectively studied. Demographic data, functional outcomes, and complications were collected and compared.

RESULTS

Within the ranks of the patients studied, we found differences between groups with respect to dislocation rate and length of stay; these were lower in the direct anterior approach (DAA) group. The approach was not associated with an increase in complications, but rather with a decrease in the rate of dislocations and better functional outcomes at 1-year follow-up. Operative time was initially higher with this approach, but equalized during the learning curve.

CONCLUSION

The DAA can be safe even in the early stages of a novice surgeon's learning curve. It does not present a higher complication rate than the posterior approach, either in infection rate or in periprosthetic fractures. However, the DAA may provide greater functionality, lower dislocation rate and a shorter hospital stay. It can also be concluded that after having performed a certain number of interventions, operative time for the DAA can be comparable to that of other approaches.

Learning Curve of Total Hip Arthroplasty in Direct Anterior Approach without Requiring Corrective Osteotomy for Hip Dysplasia

OBJECTIVE

To explore the learning curve of total hip arthroplasty in direct anterior approach (DA-THA) without requiring corrective osteotomy for patients with unilateral developmental dysplasia of the hip (DDH) through the evaluation of clinical and radiographic results.

METHOD

From December 2015 to January 2021, we retrospectively evaluated a surgeon's first 100 patients with unilateral hip dysplasia (Crowe I-III) who underwent DA-THA. All procedures were performed by a fellowship-trained joint surgeon. Cementless hemispheric porous-coated acetabular cups and tapered cementless stems were used in all hips. The radiographic data, including leg length, the height of the center of rotation, femoral head offset, the cup anteversion and inclination angle, were measured. The cumulative sum analysis (CUSUM) and risk-adjusted cumulative sum analysis (RA-CUSUM) were used to determine the learning curve of DA-THA for each patient's operation time. By analyzing the operation time, complication rate, postoperative length of hospitalization and creatine kinase (before surgery and the third day after surgery), estimated blood loss, Harris score, radiographic data were compared between the different stages of the learning curve.

RESULTS

The mean follow-up time was 35.45 ± 16.82 months. The CUSUM method obtained the maximum turning point of the curve at 43 cases, which divided the learning curve into Learning Period and Mastery Period. The CUSUM learning curve was best modeled as a cubic curve with the equation: CUSUM (min) = 0.001x³  - 0.495x²  + 33.60x - 10.00, which had a higher R² value of 0.967. The pre-operative data, creatine kinase, estimated blood loss and postoperative Harris scores of the two stages were not statistically significant (P > 0.05). The mean operation time was 118 min in the Learning Period and 87 min in the Mastery Period. Statistically significant differences were detected in the operation time (P < 0.001), postoperative length of hospitalization(P = 0.024), and postoperative leg length discrepancy (P = 0.012) between the two stages. The overall complication rates were 27.9% in the Learning Period and 12.3% in the Mastery Period (p = 0.049). The overall outliers of radiographic data were 34 cases in the Learning Period and 31 cases in the Mastery Period (79.07% vs 54.39%, P = 0.010).

CONCLUSIONS

The DA-THA is a valuable alternative to achieve satisfactory clinical results for mild-to-moderate DDH patients. Furthermore, accurate analysis of the learning curve of DA-THA for hip dysplasia by the CUSUM method showed that the surgeons need to finish about 43 cases to master the technique.

Defining the Learning Curve of Anterior Total Hip Arthroplasty After Fellowship-specific Training

PURPOSE

To investigate the learning curve associated with performing direct anterior total hip arthroplasty (THA) immediately after fellowship training in this approach.

METHODS

This was a multicenter, retrospective study that collected data on all direct anterior THAs performed by four fellowship-trained arthroplasty surgeons in their first year of practice. Demographic data, surgical time, blood loss, surgical complications, and medical complications were recorded. Regression models were created to evaluate the outcomes of interest. A generalized linear mixed model was used to estimate the effect of the number of THA procedures performed, a proxy for surgical experience with this procedure, on the variables of interest.

RESULTS

A total of 286 patients undergoing direct anterior THA were included in this study. A decrease in surgical complications after approximately 40 cases and a decrease in medical complications at 25 to 50 cases were observed. Both surgical time and blood loss showed no learning curve.

CONCLUSION

Extensive training with a direct anterior approach during fellowship minimizes the learning curve for blood loss and surgical time, but it continues to exist regarding perioperative surgical and medical complications. Recent fellowship graduates should be cautious and expect a learning curve of around 40 cases before complication rates begin to normalize.

Direct anterior approach for total hip arthroplasty with patients in the lateral decubitus versus supine positions: A prospective, double-blinded, randomized clinical trial

PURPOSE

The direct anterior approach (DAA) for total hip arthroplasty (THA) can be performed with patients in either in the lateral decubitus or supine position. Prompted by the lack of studies addressing differences between the two positions, this investigation aimed to examine clinical and radiographic outcomes and compare the lateral decubitus versus the supine position for THA using the DAA.

METHODS

Between January 1 and October 1, 2020, 90 patients who underwent primary unilateral THA using the DAA were recruited, with 54 (60%) undergoing THA in the supine position (SP group) and 36 (40%) in the lateral decubitus position (LP group). Technical information, clinical and radiographic outcomes, and patient-reported outcomes, including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short-Form-12 (SF-12) were evaluated. All data were subjected to several statistical tests.

RESULTS

There were no preoperative differences in baseline characteristics between the LP and SP groups, which were also similar in terms of operative duration, length of hospital stay, and blood loss. Radiographic assessment confirmed satisfactory positioning of the prosthesis in both groups. There were no significant differences in terms of CK-MB and hemoglobin levels, Harris Hip Score, WOMAC, UCLA, visual analog scale score, and SF-12. The incidence of complications in the LP group was lower than in the SP group.

CONCLUSION

Total hip arthroplasty performed via DAA in the LP and SP groups yielded excellent clinical outcomes, although the incidence of complications in the former was lower than in the latter.

Incidence of lateral femoral cutaneous nerve lesions after direct anterior approach primary total hip arthroplasty - a literature review

INTRODUCTION

Lesions of the lateral cutaneous femoral nerve are a reported complication of the direct anterior approach (DAA) for total hip arthroplasty (THA). Little is known about the incidence rates of this lesion. The goal of this study was to answer the following questions: (1) Is the true incidence rate of LFCN lesions after DAA THA known? (2) What are the reasons for the wide range of reported incidence rates in the literature? (3) Are surgeons increasingly aware of the significance of LFCN lesions?

METHODS

A US Medical Library of Medicine database search was performed for DAA THA. In total, 1261 search results were screened for reported LFCN lesions.

RESULTS

Forty-five studies were included reporting LFCN lesions rates of 0-83%. Subgroup analysis for studies with (group A, 6 studies, n=1113 cases) and without (group B, 39 studies n=16,741) primary focus on the LFCN lesions was performed. Incidence in group A ranged from 14.8-81% (mean 31%) and 0-83% (mean 3.8%) in group B. The difference between the groups was significant (p=0.005). No uniform and time sensitive definition of postoperative LFCN lesions was found in the literature. An analysis of the publication year and the discovered incidence rate showed an increase of incidence rates [rs=0.521 (p<0.001, two-tailed)] over time.

CONCLUSION

Despite the absence of a uniform definition: LFCN lesions after DAA THA are a frequent and, in the past, often underestimated complication.

LEVEL OF EVIDENCE

IV; systematic review of level II to level IV studies.

Modern Suture Anchor Techniques for Gluteus Medius Tear Repair With Concomitant Total Hip Arthroplasty Using the Direct Anterior and Posterior Approaches

Gluteus medius (GM) tears are currently a well-established source of pain and disability. However, their role in primary total hip arthroplasty (THA) in the setting of osteoarthritis (OA) has been underexamined in the literature. The purpose of this study was to report on short-term patient-reported outcome measurements (PROMs) for patients who underwent concomitant primary THA and GM repair. Data were prospectively collected from September 2011 and June 2017. Inclusion criteria were primary THA along with concomitant GM repair and complete follow-up for the Harris Hip Score, Forgotten Joint Score 12, Veterans RAND 12-item Health Survey both Physical and Mental, 12-item Short Form Survey both Physical and Mental (SF-12 P and SF-12 M), visual analog scale for pain, and patient satisfaction. Patients were excluded if they did not have follow-up. Thirty patients (30 hips) were included. Mean follow-up was 24.2±19.3 months. Twenty-nine (96.7%) patients were female. Mean age was 65.2±7.4 years. Mean body mass index was 31.1±5.9 kg/m². The posterior approach was used for 16 (53.3%) cases and the anterior approach for the remaining 14 (46.7%). Two (6.7%) patients had a less than 25% tear, 7 (23.3%) had a 25% to 50% tear, 14 (46.7%) had a greater than 50% tear, and 7 (23.3%) had a full-thickness tear. All PROMs except SF-12 M demonstrated significant improvement at latest follow-up. Patients who underwent THA with either the anterior or the posterior approach with concomitant GM repair using modern suture anchor techniques reported favorable PROMs at short-term follow-up. [Orthopedics. 2021;44(5):e653-e660.].

Bikini Incision Increases the Incidence of Lateral Femoral Cutaneous Nerve Injury in Direct Anterior Approach Hip Arthroplasty: A Prospective Ultrasonic, Electrophysiological, and Clinical Study

BACKGROUND

Lateral femoral cutaneous nerve (LFCN) injury has been widely reported as one of the most common complications of direct anterior approach (DAA) hip arthroplasty. Bikini incision is considered to increase the incidence of this complication.

METHODS

A prospective randomized study was conducted after including ninety-nine bikini and ninety-six longitudinal incision DAA cases from May to November 2020. The occurrence of LFCN was examined using ultrasound before and after surgery. The recovery of injury symptoms was evaluated by continuous clinical follow-up until six months, and the patients were treated with mecobalamin and/or celecoxib. Sensory conduction velocity and sensory action potential amplitude of the LFCN were measured after surgery in symptomatic patients.

RESULTS

Eighty five (43.6%), sixty seven (34.4%), and forty three (22.0%) cases of LFCN were of the anterior trunk, posterior trunk, and fan types, respectively, before surgery. All one hundred ninety five patients completed the follow-up period. Fifty-seven patients had symptoms of LFCN injury, including thirty six and twenty one patients in the bikini group and longitudinal group, respectively, with significantly different incidence rates (36.4% and 21.9%, respectively; P < .05). Of these, thirty two (56.1%), thirteen (22.8%), and twelve (21.1%) cases were of the anterior trunk, posterior trunk, and fan types, respectively. Sensory conduction velocity and sensory action potential amplitude significantly decreased after surgery in both groups (P < .05). Seventeen cases showed reduction of symptoms within three months. Forty six cases showed self-recovery within six months and eleven cases showed persistent symptoms at the final follow-up.

CONCLUSION

Bikini incision DAA hip arthroplasty may increase the incidence of LFCN injury, and the anterior trunk distribution type is most likely to be affected. (Clinical Trial Registration Number: CHICTR2000035107).

The learning curve for the direct anterior total hip arthroplasty: a systematic review

BACKGROUND

The direct anterior approach (DAA) for total hip arthroplasty (THA) is a muscle-sparing approach thought to have less post-operative pain and quicker recovery, with similar functional outcomes to other approaches. However, it is technically challenging and transitioning surgeons may experience increased complication rates. The purpose of this systematic review is to identify reported learning curves associated with the DAA.

METHODS

Three databases (MEDLINE, Embase, and Web of Science) were searched using terms including "total hip arthroplasty," "direct anterior approach," and "learning curve." Study characteristics, patient demographics, learning curve analyses, and complications were abstracted.

RESULTS

Twenty-one studies met inclusion criteria, with a total of 9738 patients (60% female), an average age of 63.7 years (range: 13-94), body mass index of 27.0 kg/m2 (range: 16.8-58.9), and follow-up of 19 months (range: 1.5-100). There were five retrospective cohort studies and 13 case series representing fair methodological quality. Six studies depicted a true learning curve, with mean operative time of 156.59 ± 41.71 minutes for the first case, 93.18 ± 14.68 minutes by case 30, and 80.45 ± 12.28 minutes by case 100. Mean complication rate was 20.8 ± 12.7% in early groups and decreased to 7.6 ± 7.1% in late groups.

CONCLUSION

This review demonstrated a substantial learning curve associated with the DAA to THA. Operative time plateaued after approximately 100 cases. Complication rates decreased substantially from early to late groups.

Restoring hip biomechanics during the learning curve of a novice surgeon: Direct anterior approach vs posterior approach

Introduction

It remains controversial whether the direct anterior approach (DAA) or the posterior approach (PA) allows better restoration of hip biomechanics after total hip arthroplasty (THA). Besides, it is not certain which approach is best for a novice surgeon to avoid implant malposition, neither during the learning curve nor once the curve plateau has been reached.

Methods

We performed a retrospective cohort study of THAs operated on between 2014 and 2019 by a single novice surgeon (DAA, n = 187; PA, n = 184). The surgeon used both approaches, and thus went through parallel learning curves.

Results

While the DAA presented a greater number of acetabular cup implantations within Lewinnek's "safe zone" for inclination (84.5% vs. 79.3%; p = 0.003), the PA returned superior results for anteversion (77.7% vs. 68.4%; p = 0.000). The PA showed a tendency to verticalize acetabular cups, while the DAA tended to antevert them. The DAA resulted in fewer patients with leg length discrepancy (3.2% vs. 8.2%, p = 0.041). No differences were found in stem coronal alignment or femoral offset.

Conclusion

Both approaches are safe and reliable for restoring hip biomechanics through THA surgery during the learning curve of a novice hip surgeon. Similar radiological outcomes are also seen once the surgeon has reached the learning curve plateau.

Dislocation rates following total hip arthroplasty via the direct anterior approach in a consecutive, non-selective cohort

AIMS

Use of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased in recent years due to proposed benefits, including a lower risk of dislocation and improved early functional recovery. This study investigates the dislocation rate in a non-selective, consecutive cohort undergoing THA via the DAA without any exclusion or bias in patient selection based on habitus, deformity, age, sex, or fixation method.

METHODS

We retrospectively reviewed all patients undergoing THA via the DAA between 2011 and 2017 at our institution. Primary outcome was dislocation at minimum two-year follow-up. Patients were stratified by demographic details and risk factors for dislocation, and an in-depth analysis of dislocations was performed.

RESULTS

A total of 2,831 hips in 2,205 patients were included. Mean age was 64.9 years (24 to 96), mean BMI was 29.2 kg/m² (15.1 to 53.8), and 1,595 patients (56.3%) were female. There were 11 dislocations within one year (0.38%) and 13 total dislocations at terminal follow-up (0.46%). Five dislocations required revision. The dislocation rate for surgeons who had completed their learning curve was 0.15% compared to 1.14% in those who had not. The cumulative periprosthetic infection and fracture rates were 0.53% and 0.67%, respectively.

CONCLUSION

In a non-selective, consecutive cohort of patients undergoing THA via the DAA, the risk of dislocation is low, even among patients with risk factors for instability. Our data further suggest that the DAA can be safely used in all hip arthroplasty patients without an increased risk of wound complications, fracture, infection, or revision. The inclusion of seven surgeons increases the generalizability of these results. Cite this article: Bone Joint J 2021;103-B(7 Supple B):38-45.

Acetabular and Femoral Component Positioning Using Direct Anterior Approach Versus Posterior Approach in Total Hip Arthroplasty

PURPOSE

Direct anterior approach (DAA) has recently become popular in total hip arthroplasty (THA). However, irrespective of the surgical approach used, component malposition is an important factor affecting function and complications after THA. This study aims to compare component positioning on the femoral and acetabular side between DAA and posterior approach (PA) to the hip joint. We hypothesized that the two approaches are similar in terms of component positioning.

METHODS

We prospectively studied 50 patients, matched according to age, sex, and body mass index, undergoing THA, divided non-randomly into 2 groups. Group 1 comprised 25 patients (35 hips) undergoing THA using DAA and group 2 comprised 25 patients (25 hips) undergoing THA using PA. Ten patients from group 1 had simultaneous bilateral THA. Radiological parameters studied were acetabular inclination (AI), coronal femoral stem alignment (CFA), leg length difference (LLD), acetabular cup version (AV), and femoral stem version (FV).

RESULTS

There was no significant difference in AI, CFA, LLD, AV, and FV between the two groups. Excellent to good inter and intra-observer reliability expressed in terms of intraclass correlation coefficient (ICC) was noted for all the radiographic measurements.

CONCLUSION

Both DAA and PA for THA achieve comparable radiological component positioning. DAA may not provide any advantage over PA in terms of positioning of the prosthesis.

LEVEL OF EVIDENCE

Level II, non-randomized comparative study.

Robotics and Navigation as Learning Tools for Fellows Training in Hip Arthroplasty

INTRODUCTION

The association between implant malpositioning and complications has been repeatedly demonstrated. Recently, technological advancements have allowed for more consistent implant placement. Beyond this obvious application, these technologies may also serve as a learning tool. Thus, the aim of this study was to evaluate the accuracy of fellows' estimation of implant positioning using a robotic system.

METHODS

Data were prospectively collected for all patients undergoing total hip arthroplasty between September 2019 and December 2019. The fellow was blinded to the robotic system. Before reaming and broaching by the senior surgeon, the fellow was asked to place the reamer at 40° of cup inclination and 20° of version. The resulting values were recorded before the true measurements were revealed. A similar process was followed for femoral broaching.

RESULTS

The mean difference between the estimated and actual cup inclination and version was 7.24° (P = 0.060) and 4.81° (P = 0.031), respectively. The mean difference in broach version was 7.00° (P = 0.159). Without the robotic system, 43.47% and 69.57% of patients would have had the cup placed outside of the safe zones described by Lewinnek and Callanan, respectively.

CONCLUSION

The estimated anteversion of the acetabular implant was found to be markedly different from its actual anteversion. A considerable portion of the cups would have been positioned outside of the Lewinnek and Callanan "safe zones" provided that the implants would have been manually positioned. The use of robotic or navigation systems may provide useful learning tools for fellows in training to understand their own inaccuracies in estimated implant position and hence refine their abilities.

Does Structured Postgraduate Training Affect the Learning Curve in Direct Anterior Total Hip Arthroplasty? A Single Surgeon's First 200 Cases

Background

The direct anterior approach (DAA) used for primary total hip arthroplasty has been shown to improve early postoperative outcomes, but prior studies have identified a marked learning curve for surgeons transitioning to this approach. However, these studies do not capture surgeons with postgraduate fellowship training in DAA. Therefore, the purpose of this study was to evaluate the learning curve by comparing perioperative outcomes for the first 100 to latter 100 cases and first 50 to final 50 cases.

Methods

The first 200 consecutive primary total hip arthroplasties performed by a single surgeon were prospectively followed up for up to 2 years postoperatively. Data on demographic and perioperative factors, 90-day readmissions, and short- and long-term complications were collected. Radiographic outcomes included acetabular cup anteversion and abduction measurements. Logistic regressions were used to calculate odds ratios and confidence intervals for surgical time greater than 2 hours.

Results

The first 100 and second 100 cases had significant differences in operative times (118.1 vs 110.4 minutes, P = .009), acetabular abduction (38.3 vs 35.5 degrees, P = .001) and anteversion (13.5 vs 15.1 degrees, P = .009), and incidence of neuropraxia (41 vs 9%, P < .001). Estimated blood loss, transfusions, discharge disposition, length of stay, readmission, and other complications had no statistical significance between the first and second 100 cases. The first 50 cases had higher odds of surgical time greater than 2 hours (odds ratio = 5.2, 95% confidence interval = 1.84-14.75, P = .002) than the final 50 cases.

Conclusions

When compared with the existing literature, incorporation of DAA into fellowship training can lead to reduction in fractures and reoperation rates.

Minimizing complications in bikini incision direct anterior approach total hip arthroplasty: A single surgeon series of 865 cases

PURPOSE

The purpose of this study was to report all complications during the first consecutive 865 cases of bikini incision direct anterior approach (DAA) total hip arthroplasty (THA) performed by a single surgeon. The secondary aims of the study are to report our clinical outcomes and implant survivorship. We discuss our surgical technique to minimize complication rates during the procedure.

METHODS

We undertook a retrospective analysis of our complications, clinical outcomes and implant survivorship of 865 DAA THA's over a period of 6 years (mean = 3.9yrs from 0.9 to 6.8 years).

RESULTS

The complication rates identified in this study were low. Medium term survival at minimum 2-year survival and revision as the end point, was 99.53% and 99.84% for the stem and acetabular components respectively. Womac score improved from 49 (range 40-58) preoperatively to 3.5(range 0-8.8) and similarly, HHS scores improved from 53(range 40-56) to 92.5(range 63-100) at final follow-up (mean = 3.9 yrs) when compared to preoperative scores.

CONCLUSIONS

These results suggest that bikini incision DAA technique can be safely utilised to perform THA.

Safely Implementing the Direct Anterior Total Hip Arthroplasty: A Methodological Approach to Minimizing the Learning Curve

INTRODUCTION

Orthopaedic surgeons often cite concern for a learning curve as a barrier to adopting the direct anterior approach (DAA) for total hip arthroplasty (THA) while transitioning from other approaches. Studies both assessing and describing a practical approach and strategy to safely accomplish this transition, as well as the effect on clinical outcomes, are not well described.

METHODS

This prospective study compares a single surgeon's operative results and complications for the first consecutive 100 direct anterior THA to the last 100 consecutive posterior THA after 7 years in practice. The regimented and disciplined learning strategy used to implement the DAA is detailed in this study. The data were analyzed using univariate and multivariate regression models.

RESULTS

Univariate analyses identified significant differences in sex, age, Asian race, and diagnostic cause for THA between the two cohorts. Multivariate analyses controlled for these differences and showed that relative to posterior THA, direct anterior THA cases were associated with 7-minute longer procedures (P = 0.002) and lengths of stay that were 0.7 days fewer (P = 0.013). No significant differences were present in the estimated blood loss, and importantly, no significant differences in death or surgical complication rates between cohorts.

DISCUSSION

This study suggests that the DAA for THA can be safely implemented without the increased and adverse risk to the patient when a structured learning process is maintained and meticulously performed.

Orthostatic retractor placement reduces operating time and post-operative inflammatory response during the learning curve of anterior approach THA

Introduction

Handheld retractor placement (HHRP) is prone to repetitive repositioning. This could lead to muscle damage especially during a procedure with a steep learning curve. In an attempt to minimize retractor repositioning during the learning curve of direct anterior approach (DAA) total hip arthroplasty (THA), we used a table mounted orthostatic retractor placement (ORP) device.

Purpose

To investigate whether ORP would reduce the extent of muscle damage, OR-time and post-operative inflammatory response.

Materials and methods

29 Patients were operated by 2 surgeons who randomly used HHRP or ORP during their learning curve of DAA THA. There were 14 patients in a control group who were operated by an experienced surgeon. Blood levels of Creatine Kinase (CK), C-Reactive Protein (CRP), Hemoglobin (Hb), Lactate Dehydrogenase (LDH) and Erythrocyte Sedimentation Rate (ESR) were measured at 1 h pre- and 24 and 48 h post-operatively.

Results

The mean OR-time was 67 and 50 min in the HHRP and ORP cohort, respectively (p < 0,001). Post-operative CRP levels were significantly higher in the HHRP cohort at 24 h (HHRP 60.64 mg/L (25.20-143.20); ORP 34.67 mg/L (9.30-71.20)) (p = 0.003) and 48 h post-operatively (HHRP 154.54 mg/L (65.90-369.00); ORP 81.60 mg/L (21.30-219.40) (p = 0.004). The post-operative Hb-levels were significantly lower in the HHRP cohort at 24 h (HHRP 11.11 g/dL (9.10-12.30); ORP 11.37 g/dL (8.80-14.00)) (p = 0.0008) and 48 h (HHRP 10.86 g/dL (9.50-12.00); ORP 11.25 g/dL (8.60-14.10)) (p = 0.03). Post-operative ESR levels were significantly higher in the HHRP cohort 48 h post-op (HHRP 45.21 mm/h (14.00-83.00); ORP 23.73 mm/h (2.00-73.00)) (p = 0.004). No significant differences were found for the CK and LDH levels at any time postoperatively. There were no complications in any group.

Conclusion

The use of an orthostatic retractor placement device allows for reducing the OR-time, post-operative blood loss and post-operative inflammatory response during the learning curve of DAA THA.

Minimum 5-Year Outcomes of Robotic-assisted Primary Total Hip Arthroplasty With a Nested Comparison Against Manual Primary Total Hip Arthroplasty: A Propensity Score-Matched Study

BACKGROUND

Robotic-assisted technology has been a reliable tool in enhancing precision and accuracy of cup placement in total hip arthroplasty (THA). Still, questions remain on the clinical benefit of this technology.

METHODS

The purposes of the ongoing study were (1) to report on minimum 5-year outcomes in patients who underwent robotic-assisted primary THA (rTHA), (2) to compare those outcomes to a propensity score-matched manual primary THA (mTHA) control group, and (3) to compare radiographic measures between the groups regarding acetabular cup placement. Prospectively collected patient data were retrospectively reviewed for primary THA recipients during June 2008 to July 2013. Patients with minimum 5-year follow-up for Harris Hip Score, Forgotten Joint Score-12, Veterans RAND-12 Mental, Veterans RAND-12 Physical, 12-Item Short Form Survey Mental, 12-Item Short Form Survey Physical, visual analog scale, and satisfaction were included. Patient-reported outcomes, cup placement, and revision rate of the rTHA group were compared with those of a propensity score-matched mTHA control group.

RESULTS

Sixty-six rTHAs were matched to 66 mTHAs. The rTHA group reported significantly higher Harris Hip Score, Forgotten Joint Score-12, Veterans RAND-12 Physical, and 12-Item Short Form Survey Physical (P < 0.001, P = 0.002, P = 0.002, P = 0.001). The acetabular implant placement by rTHA had a 9 and 4.7-fold reduced risk of placement outside the Lewinnek and Callanan safe zones, respectively (relative risk, 0.11 [95% confidence interval, 0.03 to 0.46]; P = 0.002; relative risk, 0.21 [95% confidence interval, 0.01 to 0.47]; P = 0.001). In addition, rTHA recipients had lesser absolute values of leg length discrepancy and global offset (P = 0.091, P = 0.001).

CONCLUSIONS

Patients who received rTHA reported favorable outcomes at minimum 5-year follow-up. Furthermore, in comparison to a propensity score pair-matched mTHA group, rTHAs reported higher patient-reported outcome scores and had 89% reduced risk of acetabular implant placement beyond the Lewinnek safe zone and 79% reduced risk of placement beyond the Callanan safe zone.

LEVEL OF EVIDENCE

Level III.

Assessment of the Learning Curve of Supercapsular Percutaneously Assisted Total Hip Arthroplasty in an Asian Population

The supercapsular percutaneously assisted total hip (SuperPATH) approach is a microinvasive approach that was developed to minimize surgical disruption of soft tissue during routine total hip arthroplasty (THA). This study was aimed at assessing early outcomes and learning curves of the SuperPATH approach in one Chinese hospital's experience. Early outcomes of the first consecutive 78 SuperPATH cases (80 hips) performed by the same surgeon were evaluated. The patients were divided into 4 groups according to the surgical order. The incision, intraoperative blood loss, hospital stay, Harris hip score, and complication occurrence in each group were evaluated. Learning curves were assessed using operative time and intraoperative blood loss as surrogates. The operation time and intraoperative blood loss of groups A and B were more than those of groups C and D, and the difference was statistically significant (P < 0.05); however, there was no statistically significant difference between the two groups (group A vs. group B, P = 0.426; group A vs. group B, P = 0.426). There was no statistically significant difference in terms of incision length and hospital stay, and Harris hip score at the last follow-up was increased with statistically significant difference when compared with that preoperatively among the 4 groups. One case of periprosthetic fracture occurred in group A. No other complication, such as joint dislocation, sciatic nerve injury, prosthesis loosening, periprosthetic infection, and deep vein thromboembolism, occurred in the 4 groups. In summary, for surgeons who are familiar with the standard posterolateral approach, they could achieve more familiarity with SuperPATH after 40 cases of surgery.

Good long-term outcomes for Direct Anterior Approach Total Hip Arthroplasty in South Africa

This study aims to assess long-term outcomes of Total Hip Arthroplasty (THA) through Direct Anterior Approach (DAA) in a developing country using traditional and novel Patient-Reported Outcomes. There were 522 patients (mean age, 56.5 years; 66.3% female) after mean follow-up 7.35 years. There were 13 revisions. Overall 5-year implant survival rate was 97.5%. Patient Joint Perception scores of 65.5% perceived a completely natural joint. Mean Hip Disability and Osteoarthritis Score was 89.1. Median Forgotten Joint Score-12 was 90 and modified Harris Hip Score was 88. Primary DAA THA in sub-Saharan Africa allows good clinical outcomes at minimum 5 years follow-up.

Transitioning the total hip arthroplasty technique from posterior approach in lateral position to direct anterior approach in supine position-risk factors for acetabular malpositioning and the learning curve

PURPOSE

Cup positioning is important for optimum hip stability, avoiding component impingement and decreasing both bearing surface wear and revision rate. Transitioning from posterior approach in a lateral position to direct anterior approach (DAA) in a supine presents unique challenges for surgeons. The aim of this study was to examine the learning curve when using standard instrumentation that was not specific to DAA.

METHODS

A consecutive retrospective series of 537 total hip arthroplasty by DAA from May 2013 to December 2017. Cup positioning was analysed on radiographs and classified whether inside or outside two safe zones (inclination 30-50° and anteversion 10-30°). The demographic data (age, BMI, gender, neck shaft angle (NSA)), surgeon's dominant side and experience were assessed as risk factors.

RESULTS

Eighty per cent of cups (n = 426) were in the combined safe zones. Eighty-eight per cent (n = 470) were in appropriate anteversion and 87% (n = 463) abduction. Two factors that were significant were identified: Cups of left hips operated by right-handed surgeons were more anteverted (OR = 4.06) and more vertical (OR = 2.23); females had a higher anteversion of the cup (OR = 2.42). Obesity, age and NSA were not risk factors for cup malposition. There was a spike of cups too horizontal at the beginning of the experience (OR = 3.86), and no learning curve was observed in the other orientations.

CONCLUSION

With our DAA technique using standard instrumentation, there were no risk factors linked to the patient identified for cup malposition. DAA-specific instrumentation is not required to achieve optimum positioning of the cup. Surgeon has to be aware of an excess of abduction at the beginning of his experience and an excess of anteversion and adduction when performing THA on the opposite side of his dominant hand.

Fully Immersive Virtual Reality for Total Hip Arthroplasty: Objective Measurement of Skills and Transfer of Visuospatial Performance After a Competency-Based Simulation Curriculum

BACKGROUND

Fully immersive virtual reality (VR) uses headsets to situate a surgeon in a virtual operating room to perform open surgical procedures. The aims of this study were to determine (1) if a VR curriculum for training residents to perform anterior approach total hip replacement (AA-THR) was feasible, (2) if VR enabled residents' performance to be measured objectively, and (3) if cognitive and motor skills that were learned with use of VR were transferred to the physical world.

METHODS

The performance of 32 orthopaedic residents (surgical postgraduate years [PGY]-1 through 4) with no prior experience with AA-THR was measured during 5 consecutive VR training and assessment sessions. Outcome measures were related to procedural sequence, efficiency of movement, duration of surgery, and visuospatial precision in acetabular component positioning and femoral neck osteotomy, and were compared with the performance of 4 expert hip surgeons to establish competency-based criteria. Pretraining and post-training assessments on dry bone models were used to assess the transfer of visuospatial skills from VR to the physical world.

RESULTS

Residents progressively developed surgical skills in VR on a learning curve through repeated practice, plateauing, on average, after 4 sessions (4.1 ± 0.6 hours); they reached expert VR levels for 9 of 10 metrics (except femoral osteotomy angle). Procedural errors were reduced by 79%, assistive prompts were reduced by 70%, and procedural duration was reduced by 28%. Dominant and nondominant hand movements were reduced by 35% and 36%, respectively, and head movement was reduced by 44%. Femoral osteotomy was performed more accurately, and acetabular implant orientation improved in VR assessments. In the physical world assessments, experts were more accurate than residents prior to simulation, but were matched by residents after simulation for all of the metrics except femoral osteotomy angle. The residents who performed best in VR were the most accurate in the physical world, while 2 residents were unable to achieve competence despite sustained practice.

CONCLUSIONS

For novice surgeons learning AA-THR skills, fully immersive VR technology can objectively measure progress in the acquisition of surgical skills as measured by procedural sequence, efficiency of movement, and visuospatial accuracy. Skills learned in this environment are transferred to the physical environment.

High Incidence of Intraoperative Fractures With a Specific Cemented Stem Following Intracapsular Displaced Hip Fracture

BACKGROUND

To reduce costs of orthopedic implants, the government decided to standardize implants used across different specialties in a group of hospitals located in the same geographic area. The usual cemented stem used in the context of intracapsular displaced geriatric hip fractures was replaced by another stem. Abnormal intraoperative calcar and trochanteric fractures were noted. The purpose of this study is to determine the incidence of intraoperative periprosthetic fractures following an intracapsular displaced hip fracture treated with this specific cemented stem compared to the previous implant.

METHODS

This is a retrospective cohort study comparing an historic cohort of hip fractures treated with the OmniFit EON (Stryker, Kalamazoo, MI) cemented stem with a new cohort of patients who received the Corail (DePuy Synthes, Warsaw, IN) cemented stem. Four orthopedic surgeons reviewed operative reports and postoperative radiographs.

RESULTS

The treatment group included 348 patients who received the Corail stem. The control group included 77 patients. The 2 groups had similar baseline characteristics (P > .05) except for the presence of dementia. Incidence of intraoperative calcar or greater trochanteric fracture was 15.5% for the Corail group and 2.7% for the control group (P < .05). No patient-related factors or surgeon-related factors were related to a higher number of fractures in the treatment group (P > .05).

CONCLUSION

The Corail cemented stem presents an abnormal number of iatrogenic intraoperative fractures following displaced femoral neck fracture in our geriatric population. No external factor seems to explain this high number of fractures. Implant design should be questioned.

LEVEL OF EVIDENCE

III.

Hip external rotation and extension angles for exposure and preparation of the proximal femur in direct anterior total hip arthroplasty: A cadaveric study

INTRODUCTION

The direct anterior approach (DAA) to total hip arthroplasty (THA) has a known learning curve, largely due to difficulty achieving exposure and visualization of the acetabulum and proximal femur for joint preparation. There is paucity of information on limb positioning and the degree of angulation at which the limb is positioned for adequate visualization. This study aimed to identify the mean angles of limb positioning necessary for adequate exposure when using two Mueller retractors for femoral preparation using traditional table.

MATERIALS & METHODS

A surgeon performed a DAA THA on 11 cadaveric hemipelves, exposing the femoral canal with two simple, robust Mueller retractors. The degree of external rotation and extension of the hip was measured.

RESULTS

Of the 11, the mean age was 77.6 years and mean BMI was 27.95. The mean external rotation angle was 56.5 ± 13.5°. The mean extension angle was 19.9 ± 6.6°.

DISCUSSION & CONCLUSION

The key technical step in this study incorporated a second robust Mueller retractor on the posterior aspect of the greater trochanter, providing maximum leverage to deliver the femur and achieve visibility while reducing angles of limb positioning thereby reducing complications, and ultimately lessening the learning curve.

A Multicenter Randomized Controlled Trial Evaluating the Effectiveness of Cognitive Training for Anterior Approach Total Hip Arthroplasty

BACKGROUND

For total hip arthroplasty (THA), cognitive training prior to performing real surgery may be an effective adjunct alongside simulation to shorten the learning curve. This study sought to create a cognitive training tool (CTT) to perform anterior approach (AA)-THA, which was validated by expert surgeons, and test its use as a training tool compared with conventional material.

METHODS

We employed a modified Delphi method with 4 expert surgeons from 3 international centers of excellence. Surgeons were independently observed performing THA before undergoing semistructured cognitive task analysis (CTA) and before completing successive rounds of surveys until a consensus was reached. Thirty-six surgical residents (postgraduate year [PGY]-1 through PGY-4) were randomized to cognitive training or training with a standard operation manual with surgical videos before performing a simulated AA-THA.

RESULTS

The consensus CTA defined THA in 11 phases, in which were embedded 46 basic steps, 36 decision points, and 42 critical errors and linked strategies. This CTA was mapped onto an open-access web-based CTT. Surgeons who prepared with the CTT performed a simulated THA 35% more quickly (time, mean 28 versus 38 minutes) with 69% fewer errors in instrument selection (mean 29 versus 49 instances), and required 92% fewer prompts (mean 13 versus 25 instances). They were more accurate in acetabular cup orientation (inclination error, mean 8° versus 10°; anteversion error, mean 14° versus 22°).

CONCLUSIONS

This validated CTT for arthroplasty provides structure for competency-based learning. It is more effective at preparing orthopaedic trainees for a complex procedure than conventional materials, as well as for learning sequence, instrumentation utilization, and motor skills.

CLINICAL RELEVANCE

Cognitive training combines education on decision-making, knowledge, and technical skill. It is an inexpensive technique to teach surgeons to perform hip arthroplasty and is more effective than current preparation methods.

Current Trends in Clinical Practice for the Direct Anterior Approach Total Hip Arthroplasty

BACKGROUND

Despite increased popularity of the direct anterior approach (DAA) for total hip arthroplasty (THA), current practice trends and specific driving factors leading to adoption are not well established.

METHODS

We conducted an electronic e-mail survey of members of the American Association of Hip and Knee Surgeons inquiring into the choice of THA surgical approach, perceptions of clinical outcomes, and economic implications associated with the DAA.

RESULTS

Of 996 total respondents (44.3% American Association of Hip and Knee Surgeons member response rate), 56.2% currently perform the DAA. DAA performers have been in practice for statistically less time than non-performers (17.0 years vs 20.9 years, P < .001). Similarly, high-volume DAA surgeons have been in practice for less time than low-volume surgeons. DAA performers felt that revision case status (79.3%), complex anatomy (65.0%), and body habitus (53.0%) were factors leading to preferential use of the posterior approach. We also provide comprehensive data for perceived outcomes comparing the DAA and posterior approach. For current non-performers, the top reasons for not utilizing the DAA were feelings of worse outcomes, no clinical benefit, and concern for the learning curve. Economically, 76.1% of DAA performers reported increased patient market share by performing the DAA while 65.8% of non-performers endorsed lost patient market share. Only 3.0% of current non-performers plan to adopt the DAA in the future.

CONCLUSION

This is the first study of its kind to highlight current trends and clinical practices from a surgeon perspective regarding the DAA. Specifically, it provides comprehensive data regarding perceptions of clinical outcomes, practice economics, and driving factors for choice of surgical approach for surgeons who do and do not perform the DAA.

Total hip arthroplasty with accolade/trident through the direct minimally invasive anterior approach without traction table: Learning curve and results after a minimum of 5 years

BACKGROUND

The direct minimally invasive anterior approach (DMIAA) in total hip arthroplasty (THA) is widely accepted. In our department the DMIAA according to Rachbauer together with the Trident cup and Accolade stem was introduced in 2004. The purpose of the study was to demonstrate the five-year results and to analyze the learning curve of a new introduced approach.

PATIENTS AND METHODS

Between July 2004 and May 2006, a consecutive series of 151 THA in 147 patients was retrospectively analyzed. All patients were planned to received a THA with the Accolade/Trident implant system using the DMIAA without traction table. Clinical and radiographic data, complications and survivorship were documented with a follow-up of at least 5 years.

RESULTS

Regarding cup implantation, there were 11 (7.3%) failed intentions to treat due to missing pressfit (8 cases) and acetabular floor perforation (3 cases). No failed intentions to treat occurred during stem implantation. Total implant survival after 5 years follow-up after exclusion of 11 cases with failed intention to treat (N=140) was 96.9% (SD 1.4; CI 94.3-99.6). After exclusion of the failed intentions to treat (N=140, N=4 in the first 20 cases), there was significant (p<0.001) difference between the first 16 implants with a 5 year-survival of 83.2% (SD 8.6; CI 66.4-100) and 95.7% (SD 0.9; CI 93.9-97.5) for the following 124 implants. Radiolucent lines were observed in Gruen zone 1 in 3.3% and in Gruen zone 1 and 2 in 1.1%.

DISCUSSION

THA with Accolade/Trident using the DMIAA without traction table according to Rachbauer temporary exposed patients to a higher risk of implant revisions, which was normalized after the first 20 cases. Results of the learning curve are comparable to other techniques using an orthopaedic traction table. After the typical learning curve, the rate of 5 years implant failure is in accordance with the registry data for non-cemented implants. The Accolade stem showed minimal radiographic signs of radiolucency.

LEVEL OF EVIDENCE

IV, retrospective, consecutive case series.

The risk of revision after total hip arthroplasty in young patients depends on surgical approach, femoral head size and bearing type; an analysis of 19,682 operations in the Dutch arthroplasty register

Background

Total hip arthroplasty (THA) is used increasingly in younger patients. There is little knowledge about the effect of THA characteristics on risk of revision, especially in young patients. Therefore, we studied the influence of both patient-related and surgical factors on the risk of revision using data from the Dutch Arthroplasty Registry (LROI).

Methods

All patients younger than 55 years with a primary THA implanted in the Netherlands between 2007 and 2017 were selected (n = 19,682). The covariates age, sex, primary diagnosis, ASA-classification, surgical approach, fixation method, bearing type, head size and year of surgery were entered into Cox proportional hazards models to calculate hazard ratios for the risk of revision.

Results

The overall 5-year survival of primary THA was 95.3% (95% CI, 94.9–95.6). Use of the anterior approach resulted in a lower risk of revision than the use of the posterolateral approach (HR: 0.66, 95% CI: 0.47–0.92). THAs with a head diameter ≥ 38 mm had a higher risk of revision (HR: 1.90, 95% CI: 1.33–2.72) than THAs with 32 mm heads. Use of MoM bearings resulted in an increased risk when compared to C-PE (HR: 1.76, 95% CI: 1.27–2.43).

Conclusion

The risk of revision in patients younger than 55 years depends on surgical approach, head size and bearing type. The anterior approach resulted in a decreased risk of revision, whereas use of ≥38 mm heads and MoM bearings resulted in an increased risk of revision for any reason.

Comparative outcomes between collared versus collarless and short versus long stem of direct anterior approach total hip arthroplasty: a systematic review and indirect meta-analysis

INTRODUCTION

Early research shows several advantages of the direct anterior approach (DAA) in THA that claimed to be as effective but less invasive than the posterior approach. However, due to the difficult femoral exposure and possible complications related to femoral preparation, this approach may result in a higher rate of undersized stems when compared to other approaches. The present authors believe that the femoral implant design (collar or collarless stem, short or long stem) in a collared femoral stem may relate to lower rates of stem subsidence and limb length discrepancy (LLD) in mid-term to long-term follow-up when compared to collarless femoral stems. However, currently, there is no consensus as to which femoral implant design is the most suitable for DAA in THA.

METHODS

This systematic review and meta-analysis aim to assess and compare postoperative complications (neurapraxia, wound infection, LFCN, hematoma, artery injury, cup malposition, embolism, fracture and implant loosening) and revision rates due to dislocation, periprosthetic fracture and implant migration after DAA using collared compared to collarless femoral stem and short femoral stem compared to long femoral stem in THA. These clinical outcomes consist of the postoperative complications and revision femoral stem due to neurapraxia, wound, LFCN and LLD. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Relevant studies that reported postoperative complications and revision of either implant were identified from Medline and Scopus from inception to June 6, 2018. Thirty-four studies were included for the analysis of DAA in THA; 23 studies were retrospective cohorts, four studies were prospective cohorts, and seven studies were RCTs. Thirty-one studies and three studies were included for analysis of collarless and collared femoral stems. Twenty-six studies were long femoral stems and eight studies were short femoral stems. Overall, there were 6825 patients (6457 in the collarless group and 368 in the collared group, 4280 in long stem and 2545 in short stem). A total of 469 and 66 patients had complications and revisions in the collarless group, and no patient had complications and revisions in the collared stem group. The total complication and revision rate per patient were 5% (95%CI 3.3%, 7%) and 0.9% (95%CI 0.6%, 1.2%) in all patients. The complication rate and revision rate were 5.7% (95%CI 3.8%, 7.7%) and 0.9% (95%CI 0.6, 1.2) in the collarless group. There was no prevalence of complications and revisions in the collared stem group. The complication rate and revision rate were 10.2% (95%CI 9%, 11.4%), 0.7% (95%CI 0.3%, 1%) and 5.2% (95%CI 3.1, 7.2), 1.5% (95%CI 1%, 2%) in short and long femoral stems, respectively. Indirect meta-analysis shows that collared femoral stem provided a lower risk of complications of 0.02 (95%CI 0.001, 0.30) when compared to collarless femoral stem. Long femoral stems had a lower risk of having complications of 0.57 (95%CI 0.48, 0.68) when compared to short femoral stems. In terms of revision, there is no statistically significant difference in collared femoral stem compared to collarless femoral stem and long femoral stem compared to short femoral stem.

CONCLUSION

In DAA THA, collared femoral stem and long femoral stem had decreased complication rates when compared to collarless femoral stem and short femoral stem by both direct and indirect meta-analysis methods. However, in terms of revision rates, there were no differences between all femoral stems (short versus long and collared versus collarless). Prospective randomized controlled studies are needed to confirm these findings as the current literature is still insufficient.