Direct Anterior Approach Total Hip Arthroplasty Research Articles

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.

23-hour Total Hip Replacement Requiring Only 3.5 Opioid Pills Through 6 Weeks: A Non-selected Prospective Consecutive One Year Cohort

Background Many treatment protocols surrounding post-surgical pain management following total hip arthroplasty (THA) rely heavily on opioid medications and conventional formal physical therapy. We hypothesized that an expanded 90-day multimodal protocol could lead to a postoperative opioid-free or significantly reduced-opioid THA recovery with little or no need for formal physical therapy. Methods Prospective consecutive patients undergoing THA were enrolled in a 3 month long (6 weeks preoperatively and 6 weeks postoperatively) multimodal protocol including a robust education and optimization program with home-based physical therapy. All patients received a direct anterior approach THA on a Hana table by a single, fellowship-trained surgeon in a community practice. Opioid consumption was recorded at preoperative, postoperative, 3 week and 6 week timepoints. Results A total of 207 consecutive patients underwent THA and completed their 6-week follow-up evaluations. Seventy-nine patients (38%) required no opioid pills, 75 (36%) used 1-5 pills, 47 (23%) used 6-10 pills and 6 (3%) used more than ten pills. Overall 97% of patients undergoing DAA THA required 10 pills or less. Of those patients who reported taking at least one opioid pill, 92/128 (72%) took tramadol rather than stronger opioids. Average number of opioids was 3.5 pills per patient. Additionally, at 6 weeks, 95% of patients required no formal physical therapy. The percentage of patients discharged home the same day was 64% with 94% home by POD #1. Average length of stay was .42 days. Conclusion This study confirms that an expanded length multimodal protocol can significantly reduce or eliminate opioid consumption following outpatient DAA THA. It additionally confirms that the majority of patients may do well with a simple home exercise program.

Dimensional Changes of Lumbar Intervertebral Foramen in Direct Anterior Approach-Specific Hyperextension Supine Position.

ObjectiveTo investigate the changes in the lumbar intervertebral foramen (LIVF) dimensions from neutral supine to direct anterior approach (DAA)‐specific hyperextension supine position through a standardized three‐dimensional (3D) reconstruction computerized tomography (CT) method.MethodsA total of 35 healthy volunteers (18 men and 17 women) were included in this retrospective study. The mean age of enrolled subjects was 28.9 ± 5.0 years. In September 2018, all the individuals underwent a 3D CT scan of the lumbar spine in neutral and 30° hyperextension supine positions, which mimicked the patient’s position in DAA total hip arthroplasty (THA). The dimensions of the LIVF, including foraminal area, height, and width, were measured on 3D reconstructed CT models at all lumbar foraminal levels. Foraminal area was defined as the area bounded by the adjacent superior and inferior vertebral pedicles, the posterosuperior boundary of the inferior vertebral body, the surface of the intervertebral disc posteriorly, the posteroinferior boundary of the superior vertebral body, and the surface of the ligamentum flavum anteriorly. Foraminal height was defined as the longest distance between the border of the superior and the inferior pedicle. Foraminal width was defined as the shortest distance between the posteroinferior edge of the superior vertebrae and the opposing boundary. Subgroup analysis and multiple linear regression were used to evaluate the relationship between percentage changes of the LIVF dimensions and side, sex, and age.ResultsThe LIVF dimensions varied significantly between the two positions at all levels (P < 0.05). From neutral to hyperextension supine position, the foraminal area reduced by 20.1% at lumbar 1–2 (L1–2), 22.6% at L2–3, 19.9% at L3–4, 18.1% at L4–5, and 12.0% at lumbar 5–sacral 1 (L5–S1) level, respectively; the foraminal height reduced by 9.5% at L1–2, 10.5% at L2–3, 9.5% at L3–4, 9.6% at L4–5, and 6.1% at L5–S1 level, respectively; the foraminal width reduced by 12.8% at L1–2, 14.5% at L2–3, 13.0% at L3–4, 10.4% at L4–5, and 8.4% at L5–S1 level, respectively. The changes in LIVF dimensions were biggest at L2–3 level and smallest at L5–S1 level. Subgroup analysis showed that there were no significant differences in the percentage changes of LIVF dimensions between the sexes and sides (P > 0.05). Multiple linear analysis showed that the percentage changes of LIVF dimensions were not related to side, sex, and age (P > 0.05).ConclusionThe dimensions of the LIVF showed significant decrease at all levels in the DAA‐specific hyperextension supine position compared with the neutral supine position, and the percentage changes of LIVF dimensions were not influenced by side, sex, and age.

Comparison of Component Placement Accuracy Using Two Intraoperative Fluoroscopic Grid Technologies During Direct Anterior Total Hip Arthroplasty

BackgroundIntraoperative fluoroscopy is beneficial when performing total hip arthroplasty (THA) via the direct anterior approach; however, image distortion may influence component placement. A manual gridding system (MGS) and a digital gridding system (DGS) are commercially available, aimed at visually representing or correcting image distortion. Therefore, the purpose of this study is to compare component placement accuracy following direct anterior approach THA when intraoperative fluoroscopy was supplemented with MGS or DGS. MethodsA retrospective evaluation of acetabular cup abduction (ABD), leg length discrepancy (LLD) and global hip offset difference (GHO) was completed for consecutive patients from 6 week post-THA weight-bearing radiographs. The predefined target LLD and GHO was <10 mm and ABD target was 45° ± 10°. Differences between MGS and DGS were determined by independent t-tests. ResultsThe MGS (250 patients, 315 hips) and DGS (183 patients, 218 hips) achieved targeted ABD in 98.7% and 96.8% of cases, respectively, and ABD was significantly lower in the MGS group (45.14 ± 4.03° and 47.01 ± 4.39°, respectively) (P < .001). Compared to MGS, the DGS group averaged significantly higher GHO (3.64 ± 2.44 and 4.45 ± 2.73 mm, respectively, P = .002) but was not significantly different regarding LLD (2.92 ± 2.55 and 3.19 ± 2.46 mm, respectively, P = .275). No significant group difference was noted for percentage within the targeted LLD and GHO; however, 93.5% of DGS and 97.6% of MGS achieved all three (P = .031). ConclusionThe use of both the MGS and DGS resulted in consistent component placement within the predefined target zone. Although the MGS appeared to be slightly more consistent, these differences are unlikely to be clinically significant.

Reasons for Failure of Primary Total Hip Arthroplasty Performed Through a Direct Anterior Approach.

The direct anterior approach (DAA) for total hip arthroplasty (THA) is a technique popular among some arthroplasty surgeons. There is currently a paucity of data regarding reasons for failure of THA using the DAA. The authors conducted a retrospective review of prospectively collected data on 56 patients who underwent revision THA at their institution after failing primary THA that was performed through a DAA either at their institution (n=8) or elsewhere (n=48) from January 1, 2010, to June 1, 2017. Patients were grouped by modes of failure and compared using patient characteristics, surgical factors, and radiographic outcomes. Total hip arthroplasties performed through the DAA failed due to infection in 21 (38%) patients, aseptic/mechanical loosening in 14 (25%) patients, intraoperative fracture in 6 (11%) patients, postoperative fracture in 6 (11%) patients, tendinitis or pain of unknown etiology in 3 (5%) patients, metallosis in 3 (5%) patients, instability/dislocation in 2 (4%) patients, and leg length discrepancy in 1 (2%) patient. Patients who underwent revision due to unrecognized intraoperative fracture had a lower body mass index (BMI) and weight than patients who had failure due to postoperative fracture, aseptic loosening, or infection. The 4 most common modes of failure included infection, aseptic loosening, unrecognized intraoperative fracture, and postoperative fracture. Together, these made up 84% of failed DAA THAs. Patients with a lower BMI are more likely to have failure due to intraoperative fractures. Patients with a higher BMI are more likely to have failure due to postoperative fracture, aseptic loosening, or infection. [Orthopedics. 2020;43(4);239-244.].

Functional outcomes of direct anterior approach hip arthroplasty: Oblique ‘bikini’ versus longitudinal skin incision

Introduction: The direct anterior approach (DAA) for hip arthroplasty has gained popularity in recent years with numerous articles suggesting that short-term outcomes are advantageous over alternative approaches. The ‘bikini’ inguinal crease line incision is a novel variant of the DAA, which reduces the scar. Methods: We conducted a retrospective cohort study to assess functional and general health outcomes and complications of the two different surgical incisions used in DAA total hip arthroplasty (i.e. ‘bikini’ and longitudinal incisions). Results: We found no statistical difference between the novel bikini incision and the traditional DAA hip arthroplasty. Conclusion: This approach offers a cosmetically improved scar with no compromise in outcomes.

Understanding the risks of total hip arthroplasty in patients with von Willebrand’s disease

Purpose: Patients with von Willebrand’s disease (VWD) have either a qualitative or quantitative deficiency in a key clotting protein called von Willebrand’s factor. Type Ⅰ disease is the most common variant, but its clinical implications in total hip arthroplasty (THA) are unclear. Our purpose is to describe the perioperative impact of VWD in THA. Methods: We retrospectively reviewed a total of 17 primary THAs in 14 patients with type Ⅰ VWD performed between 2008 and 2019. Almost all cases (88%) received tranexamic acid, and most (59%) received DDAVP. All patients had a direct anterior approach (DAA) THA. Results: None of these cases required a blood transfusion. Mean estimated blood loss was 229 mL, and the mean hemoglobin dropped from 13.9 g/dL to 10.2 g/dL. There were no major bleeding complications. After a mean follow-up of 4 years, the mean hip disability and osteoarthritis outcome score, junior (HOOS, JR) was 79, and there were no reoperations or revisions for any cause. Conclusion: Patients with type Ⅰ VWD do not experience severe bleeding with routine chemoprophylaxis combined with DAA THA.

Direct anterior approach total hip arthroplasty for Crowe III and IV dysplasia.

High-dislocated hip dysplasia is challenging to treat with total hip arthroplasty via the direct anterior approach (DAA). The DAA has potential advantages including optimizing component positioning, enhanced hip stability, and a more rapid postoperative recovery. We present a surgical technique for DAA total hip arthroplasty for hip dysplasia that includes preoperative planning, soft tissue releases, subtrochanteric osteotomy, component placement, and intraoperative nerve monitoring and imaging. This technique provides detailed technical instructions, specifically including pearls and pitfalls, and complication prevention strategies.

Hidden blood loss in direct anterior total hip arthroplasty: a prospective, double blind, randomized controlled trial on topical versus intravenous tranexamic acid.

Despite a plethora of literature reporting on the use of tranexamic acid (TXA) in total hip arthroplasty (THA), little is available on its effect on post-operative hidden blood loss and even less on its use in the direct anterior approach (DAA), which is gaining popularity. This study was designed as a prospective, double blind, single centre, randomized controlled trial. Sixty patients were allocated to intravenous administration of 1.5g of TXA just before wound closure while 60 patients were allocated to topical application of 3.0g of TXA via a subfascial drain at the end of the procedure. Post-operative blood loss was (1) calculated via a well-established formula based on pre- and post-operative Hb levels, patients characteristics and intra-operative blood loss and (2) measured via the amount that collected in the subfascial drain over time. No statistical significant difference in post-operative blood loss was found, neither when the formula was used (0.55L [topical] vs 0.67L [IV]; p = .140) nor when looking at the drain output (0.25L [topical] vs 0.29L [IV]; p = .108). No significant difference in secondary outcome measures, such as transfusion of units of packed red blood cells, length of hospital stay or the occurrence of venous thromboembolisms, could be found either. This study provides detailed insights into the intra- and post-operative blood loss in DAA THA and shows that topical and IV TXA have similar effects on hidden blood loss. Clinical Trial Number: NCT01940692. Level I-Randomized Controlled Trial.

Perioperative Fracture Risk and Two-Year Survivorship of a Short Tapered Femoral Stem following Direct Anterior Approach Cementless Total Hip Arthroplasty with a Fracture Table

AbstractThe cementless, tapered wedge, short femoral stem implant is commonly used in direct anterior approach (DAA) total hip arthroplasty (THA). The lack of access and visualization, however, may increase the risk of perioperative fracture and early failure. Therefore, the current study examined perioperative complications and 2-year implant survivorship following DAA THA performed using a fracture table and short, tapered wedge femoral stem. A retrospective analysis was conducted on patients having undergone DAA THA with a cementless, tapered wedge, short femoral stem. Perioperative fractures were noted and survivorship was determined by the incidence of revision surgery within a minimum 2-year follow-up period. A total 366 consecutive patients (441 hips) were identified in the cohort. Four patients (6 hips; 1.4%) were lost to follow-up and three patients died from unrelated causes. Average follow-up time for the remaining 359 patients (435 hips) was 32.9 ± 10.2 months. There were no intraoperative factures but three perioperative fractures within two weeks. Aseptic loosening occurred in one stem at 13 months, resulting in a 99.1% survival rate with a mean survival time of 23.8 ± 0.1 months (95% confidence interval: 23.6–24.0 months). The use of a short, tapered wedge femoral stem and a fracture table for DAA THA resulted in 0.7% periprosthetic fractures and only one aseptic loosening within 2 years. These results suggest that proper femoral exposure with the use of a fracture table and a short, tapered wedge femoral stem does not appear to increase the risk of periprosthetic femoral fracture.

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

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. 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. 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. 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.

Traction table versus standard table total hip arthroplasty through the direct anterior approach: a systematic review.

The direct anterior approach (DAA) for total hip arthroplasty (THA) was originally performed with a supine patient on a specialised traction table, but the approach can also be performed on a standard operating table. Despite cost and safety implications, there are few studies directly comparing these techniques and table choice remains largely surgeon preference. The purpose of this review was to compare the clinical outcomes and complication profiles of traction and standard table DAA for primary THA. The authors searched databases for relevant studies, screening in duplicate. Study quality was assessed using MINORS criteria or Cochrane Risk of Bias Tool. Data pertaining to patient demographics, clinical outcomes, and complications were abstracted. Of 3085 initial titles, 44 studies containing a total 26,353 patients were included and analysed. Mean operative time was 70.9 ± 21.2 minutes for standard table (n = 4402) and 100.1 ± 32.6 minutes for traction table (n = 3518). Mean estimated blood loss was 382.3 ± 246.4 mL for standard (n = 2992) and 531.7 ± 364.3 mL for traction table (n = 2675). Intra-operative fracture rate was 1.3% for standard table (n = 3940) and 1.7% for traction table (n = 8386). Complication rates including revisions, dislocations and peri-prosthetic fractures were qualitatively similar between traction and standard table studies. Standard table and traction table DAA have similar outcomes and complications. Both techniques offer the short-term advantages of DAA when compared to other THA approaches. However, the standard table technique may offer perioperative advantages including decreased blood loss, shorter operative time, and fewer intraoperative fractures. In the context of rising global healthcare costs and lack of access to specialised orthopaedic traction tables, this review at minimum confirms the short-term safety of standard table DAA THA and prompts the need for future studies to directly compare these techniques.

Does the use of intraoperative fluoroscopy improve postoperative radiographic component positioning and implant size in total hip arthroplasty utilizing a direct anterior approach?

BackgroundThe direct anterior approach (DAA) for total hip arthroplasty (THA) has gained recent popularity, with 1 purported benefit being access to intraoperative fluoroscopy. However, there are limited data demonstrating improved component position with the use of intraoperative fluoroscopy. The aim of this study is to compare radiographic implant positioning on 2 consecutive cohorts of patients undergoing DAA THA performed by 1 surgeon either utilizing intraoperative fluoroscopy or not. We hypothesized that there would be no relevant radiographic differences between the cohorts.MethodsForty-two consecutive patients underwent DAA THA utilizing fluoroscopy (IFC), and 42 consecutive patients then underwent DAA THA without fluoroscopy (NFC). Using preoperative pelvis radiographs and 6-week postoperative pelvis radiographs, acetabular anteversion, inclination, femoral offset, and templated component sizes vs final intraoperatively selected sizes were recorded and compared between cohorts.ResultsAcetabular inclination was 45.0° for IFC and 45.6° for NFC (P = .629). Femoral offset difference preoperatively and postoperatively was 0.8 mm for IFC and 1.3 mm for NFC (P = .734). Number of hips within the so-called safe zone was 32 for IFC and 33 for NFC (P = .794). These all demonstrated no significant difference between the cohorts. However, acetabular anteversion was 13.7° for IFC and 11.2° for NFC (P = .02).ConclusionsIn this limited series, the routine use of intraoperative fluoroscopy did not improve implant positioning or sizing. This may be surgeon-specific or due to the result of the use of acetabular landmarks to guide placement of the components without fluoroscopy.

Anterior acetabular retractors and the femoral neurovascular bundle in anterior total hip arthroplasty: a cadaveric study.

The direct anterior approach for primary total hip arthroplasty (THA) has become increasingly popular in recent years. Nerve compression or traction with a retractor is a common cause of nerve injury in this approach. The purpose of this cadaveric study was to evaluate the anatomic relationship of the femoral neurovascular bundle to the anterior acetabular retractor during direct anterior approach THA. Eleven fresh-frozen cadavers underwent a standard direct anterior THA, with placement of an anterior acetabular retractor in the usual fashion between the iliopsoas and acetabulum for visualization during acetabular preparation. Careful dissection of the femoral triangle was performed, and the distances from the anterior retractor tip to the femoral nerve, artery, and vein were recorded and analyzed as mean distance ± standard deviation. In all 11 cadavers, the retractor tip was medial to the femoral nerve. The mean distance from retractor tip to femoral artery and vein was 5.9mm (SD = 5.5, range 0-20) and 12.6mm (SD 0.7, range 0-35), respectively. Surgeons should be aware of the proximity of the neurovascular structures in relation to the anterior acetabular retractor in the direct anterior approach, taking care to avoid perforating the iliopsoas muscle during retractor insertion and limit excessive traction to prevent nerve injury.

Direct Anterior Approach in Total Hip Arthroplasty Leads to Superior Outcomes at 3-Month Follow-up When Compared With the Posterior Approach: A Matched Study Using Propensity Score Analysis.

Objective:The purpose of this study was to report and compare early outcomes during the first 3 months of the recovery phase in patients who underwent primary total hip arthroplasty (THA) with direct anterior approach (DAA) and posterior approach (PA).Background:The DAA for primary THA has gained popularity within the past few years. Although controversy exists regarding the long-term benefit when compared with the PA, several authors have reported markedly better outcomes in the early recovery weeks, when using DAA.Methods:For this study, data were prospectively collected and retrospectively reviewed for all primary THAs from March 2014 to October 2017. Included patients underwent primary THA through DAA or PA and had minimum 3-month postoperative measures for the Harris Hip Score, Forgotten Joint Score-12, Veterans RAND 12 Mental (VR-12 Mental), Veterans RAND 12 Physical (VR-12 Physical), 12-Item Short-Form (SF) Survey Mental, 12-Item SF Survey Physical (SF-12 Physical), Visual Analog Scale, and patient satisfaction. An analysis using propensity score matching was done to establish the DAA and PA groups. Matching (1:1 ratio) was conducted based on the following covariates: age, sex, body mass index, and laterality.Results:Twenty-four DAA THA patients were successfully matched using propensity scoring to 24 PA THA patients. The DAA group demonstrated significantly higher scores for the following patient-reported outcome scores: Harris Hip Score, VR-12 Mental, VR-12 Physical, and SF-12 Physical (P = 0.0090, P = 0.0388, P = 0.0063, and P = 0.0132, respectively).Conclusion:At 3-month follow-up, both the DAA and PA groups reported favorable outcomes after THA. However, the DAA group scored markedly higher regarding quality-of-life outcomes when compared with a propensity score–matched group of PA patients.

Heterotopic Ossification after Direct Anterior Approach Total Hip Arthroplasty

AbstractPrevious studies have demonstrated varying rates of heterotopic ossification (HO) after total hip arthroplasty (THA) depending on which anatomical approach is utilized. The direct anterior approach (DAA) is considered to be a muscle-sparing approach to the hip, which may lead to decreased rates of HO formation. This study evaluated the incidence of HO formation after DAA THA. The current work is a retrospective review of patients who underwent DAA THA. Six-month postoperative radiographs were evaluated and HO grade was classified using the Brooker classification system. Baseline characteristic differences between the Brooker classification groups were analyzed, specifically looking at: age, sex, type of deep venous thrombosis prophylaxis utilized, and preoperative Bombelli arthritis type. The overall incidence of HO in this DAA group was 179/485 patients (36.9%). There were 14 patients (2.9%) with Brooker Type 3 HO and 1 patient (0.21%) with Brooker Type 4 HO. No surgical excision of HO was performed. Patients were significantly more likely to develop HO if they had Bombelli hypertrophic arthritis (p &lt; 0.00003). Preoperative radiographic imaging suggesting Bombelli hypertrophic arthritis is predictive of HO formation, warranting consideration for HO prophylactic treatment. The radiographic incidence of HO in DAA THA was 36.9%, which is within the previously reported range of HO seen for lateral and posterior approaches to the hip. HO after total hip arthroplasty is likely due to soft tissue handling, hemostasis, and patient factors, rather than type of surgical approach.

Hospital Adverse Events and Perioperative Outcomes in Bilateral Direct Anterior Approach Total Hip Arthroplasty

BackgroundPerioperative hospital adverse events represent a significant outcome that is often overlooked. Even “minor events” such as fever or tachycardia may lead to significant costs due to workup tests, interconsultations, and/or increased length of stay (LOS). The optimal timing of bilateral direct anterior approach total hip arthroplasty (DAA-THA) remains unsettled. Consequently, we wanted to compare hospital LOS, discharge disposition, hospital adverse events (major and minor), and transfusion rates between simultaneous and staged bilateral DAA-THA. MethodsA retrospective chart review was conducted on a consecutive series of 347 primary bilateral DAA-THAs (204 patients) performed by 2 surgeons in a single institution (2010-2016). The hips finally included were categorized as simultaneous (Sim-n = 61), staged 1 (Stg1-n = 143), or staged 2 (Stg2-n = 143). We also compared simultaneous with staged surgeries performed ≤1 and >1 year apart. Baseline demographics, LOS, discharge disposition, hospital adverse events, and transfusions were assessed. ResultsThe simultaneous group had significantly younger patients and a higher proportion of males when compared with the staged groups and showed significant longer LOS [2.61 (Sim) vs 2.06 (Stg1) vs 1.63 (Stg2) days, P < .001], lower proportion of home discharge [77% (Sim) vs 91.6% (Stg1) vs 96.5% (Stg2), P < .001], as well as higher (overall) rate of adverse events [31.1% (Sim) vs 28.7% (Stg1) vs 14.0% (Stg2), P = .003] and transfusions [45.9% (Sim) vs 6.3% (Stg1) vs 7.0% (Stg2), P < .001]. However, most transfusions were autologous [37.7% (Sim) vs 3.5% (Stg1) vs 0% (Stg2), P < .001]. ConclusionOur data show that bilateral DAA-THAs performed in a staged fashion, rather than simultaneously, have a shorter hospital LOS and decreased rates of adverse events and overall transfusions. Notwithstanding, simultaneous surgery should still be considered an option in selected patients. Level of EvidenceLevel III.

Prospective Evaluation of the Posterior Tissue Envelope and Anterior Capsule After Anterior Total Hip Arthroplasty

BackgroundFemoral exposure for direct anterior approach (DAA) total hip arthroplasty (THA) invariably requires posterior soft tissue releases. Released posterior structures cannot be repaired. The purpose of this study is to describe the frequency and anatomic consequences of DAA THA posterior soft tissue releases and to compare the appearance of the anterior capsule between a group of patients who had capsulotomy and repair versus capsulectomy. MethodsThirty-two DAA THA patients underwent metal artifact reduction sequence magnetic resonance imaging at discharge and 1-year follow-up. Seventeen had underwent capsulotomy and repair and 15 capsulectomy. A radiologist blinded to intraoperative data scored each metal artifact reduction sequence magnetic resonance imaging. Anterior capsular integrity, status of the piriformis and conjoint tendons, and muscle atrophy were graded. Descriptive statistics were performed to analyze results. ResultsImmediately postoperatively, 75% of piriformis tendons were intact and 38% of conjoined tendons were intact. At 1 year, 97% had an intact piriformis and conjoined tendon, although many were in continuity through scar with the capsule. The posterior capsule directly contacted bone in all patients. At 1 year, none of the patients who underwent capsulotomy with repair had persistent anterior capsule defects, while 27% in the capsulectomy group had persistent defects. ConclusionPosterior capsule and conjoined tendon releases were commonly performed during DAA THA, yet continuity with bone was frequently achieved at 1 year. In this study, capsulotomy with repair resulted in no anterior capsular defects when compared with capsulectomy. These results may support improved THA stability observed after DAA with capsular repair despite posterior soft tissue releases. Level of EvidenceLevel III, prospective cohort study.

Intraoperative measurement of cup inclination using fluoroscopy requires a correction factor.

Malpositioning of the cup in total hip arthroplasty (THA) is associated with dislocation, early polyethylene wear, and impingement. The direct anterior approach (DAA) THA allows for intraoperative fluoroscopy imaging (IF). The current study investigates the following research hypotheses: (1) intraoperative measurements of radiographic cup inclination (RI) are reliable and reproducible. (2) A correction factor can compensate for the complex parallax effects when using IF. In 2016, 100 consecutive hips underwent primary THA utilizing DAA and IF for cup placement. RI was measured on intraoperative fluoroscopy images and postoperative AP pelvis radiographs. Determination of RI on IF images is reliable and reproducible (ICC 0.851-0.950). RI measurement on IF images had a good correlation with the corresponding postoperative RI on AP pelvis radiographs (r = 0.538, p < 0.001). However, intraoperative RI measurements are on average 4.9° lower compared to postoperative measurements (SD 2.5°). Intraoperative fluoroscopy is a reliable tool to measure RI during DAA THA. The surgeon needs to apply a 5°. correction factor to the intraoperative measurements to adjust for parallax.

Outcome of Direct Anterior Total Hip Arthroplasty Complicated by Superficial Wound Dehiscence Requiring Irrigation and Debridement

BackgroundSuperficial wound dehiscence after total hip arthroplasty (THA) performed through the direct anterior approach (DAA) can be treated with superficial irrigation and debridement (I&D). The incidence and treatment of this complication has been described, but there are little data on the outcomes after a superficial I&D have not been described. The purpose of this paper was to examine the clinical outcomes of DAA THAs requiring postoperative superficial I&D. MethodsA retrospective review of 1573 THAs performed using the DAA were identified utilizing a prospectively collected, single-institution joint registry. Of these 1573 cases, 18 THAs in 18 patients (1.1%) underwent a superficial I&D for superficial wound dehiscence. Outcomes studied included prosthetic joint infection (PJI) after superficial I&D, revisions, re-reoperations, complications, and clinical outcome scores. ResultsSurvivorship from superficial I&D at 1, 2, and 5 years postoperatively was 98.6% at all time points. In the 18 patients who underwent superficial I&D, this was performed an average of 37 (range 12-83) days after their THA. Female gender (hazard ratio 5.5, 95% confidence interval 1.20-32.34, P = .0271) was associated with a higher risk of undergoing superficial I&D as was body mass index >30 kg/m2 (P = .0028), >35 kg/m2 (P < .0001), and >40 kg/m2 (P = .0037). At average follow-up of 2.2 (range 0.2-5.5) years, 0 patients developed PJI. Complications included femoral revision for a painful fibrously ingrown femoral component (1), pulmonary embolus (1), and death from respiratory failure (1). Postoperative Harris Hip Scores averaged score was 86.8 (range 57-99). ConclusionsSuperficial wound dehiscence requiring superficial I&D after DAA THA occurs in about 1%-2% of patients with low risk of subsequent PJI.