Direct Anterior Approach Research Articles

Direct Anterior Approach Total Hip Arthroplasty for Femoral Neck Fractures in the Lateral Position.

To compare the clinical efficacy of artificial total hip arthroplasty(THA) for femoral neck fracture between direct anterior approach(DAA) in lateral position and posterior lateral approach(PLA). Comparison of 200 cases of patients who underwent THA collected between September 2019 and August 2021 was done. Incision length, intraoperative bleeding, operative time, difference in postoperative haemoglobin from preoperative levels, length of hospital stay, postoperative time to get off the floor, visual analogue score (VAS) for pain, preoperative and postoperative Harris scores for the hip, and measurements of the acetabular abduction angle and anterior acetabular tilt angle at 6 months postoperatively were collected, and all the cases were followed up for at least 2 years. Compared with the PLA group, the DAA group had a shorter incision length, less intraoperative blood loss, less postoperative haemoglobin reduction compared with the preoperative period, a shorter hospital stay and an earlier first time to get off the floor after surgery, however, the comparison of operative times was not statistically significant; Patients in the DAA group had a lower VAS in the early postoperative period compared to PLA; Patients in the DAA group had higher hip Harris scores at 6 weeks and 6 months postoperatively; There was no significant difference in acetabular abduction angle and acetabular anterior tilt angle between the two groups at 6 months postoperatively. Compared to PLA, DAA in THA is minimally invasive, has less pain, less bleeding, earlier time out of bed, shorter hospital stay, better early hip function, faster rehabilitation, and better joint stability.

Comparison of Early Postoperative Step and Stair Counts With the Direct Anterior Approach Versus the Posterior Approach for Total Hip Arthroplasty

BackgroundThe purpose of this study was to evaluate the impact of direct anterior approach (DAA) or posterior approach (PA) on step and stair counts after total hip arthroplasty using a remotely monitored mobile application with a smartwatch while controlling for baseline characteristics. MethodsThis is a secondary data analysis from a prospective cohort study of patients utilizing a smartphone-based care management platform. The primary outcomes were step and stair counts and changes from baseline through one year. Step and stair counts were available for 1,501 and 847 patients, respectively. Longitudinal regression models were created to control for baseline characteristics. ResultsPatients in the DAA group had significantly lower body mass index (P = .049) and comorbidities (P = .028), but there were no significant differences in age (P = .225) or sex (P = .315). The DAA patients had a higher average and improvement from baseline in step count at 2 and 3 weeks postoperatively after controlling for patient characteristics (P = .028 and P = .044, respectively). The average stair counts were higher for DAA patients at one month postoperatively (P = .035), but this difference was not significant after controlling for patient demographics. Average stair ascending speeds and changes from baseline were not different between DAA and PA patients. Descending stair speed was higher at 2 weeks postoperatively for DAA patients, but was no longer higher after controlling for baseline demographics. ConclusionsAfter controlling for baseline characteristics, DAA patients demonstrate earlier improvement in step count than PA patients after total hip arthroplasty. However, patient selection and surgeon training may continue to influence outcomes through a surgical approach.

Anterior Minimally Invasive Approach (AMIS) for Total Hip Arthroplasty: Analysis of the First 1000 Consecutive Patients Operated at a High Volume Center.

(1) Background: Direct anterior approach (DAA) has recently acquired popularity through improvements such as the anterior minimally invasive surgical technique (AMIS). This retrospective study examines the first 1000 consecutive THAs performed utilizing the AMIS approach in a high-volume center between 2012 and 2017. (2) Methods: 1000 consecutive THAs performed at a single institution utilizing the AMIS approach were retrospectively analyzed with a minimum five-year follow-up. Full evaluation of demographic information, clinical parameters, intraoperative complications, and radiological examinations are reported. (3) Results: Overall complication rate was 9.4% (94/1000), including 8 dislocations, 57 femoral-cutaneous nerve injuries, 12 intraoperative femoral fractures, 9 infections and 8 leg length discrepancy. Implant survival rates were 98.5% at 1 year, 97.5% at 3 years, 97% at 5 years, and 95.3% at 7 years. Causes of failure included periprosthetic fractures (0.8%), implant dislocations (0.6%), septic loosening (0.5%), aseptic mobilizations (0.2%), and symptomatic limb length discrepancies (0.2%). (4) Conclusions: Controversies persist around the direct anterior approach (DAA) for THA, primarily regarding the increased complications rate during the learning curve. However, this study advocates for widespread adoption of the DAA approach. The results demonstrate acceptable complication rates and remarkable functional outcomes, affirming its viability in the broader orthopedic patient population.

Similar incidence of postoperative sciatic nerve palsy in direct anterior and posterior approach total hip arthroplasty.

Sciatic nerve palsy is a rare but devastating complication following total hip arthroplasty (THA). While the use of the direct anterior approach is increasing, limited data exist regarding sciatic nerve palsy and surgical approach. The purpose of this study was to determine the factors and outcomes associated with sciatic nerve palsy (SNP) after THA. A retrospective analysis was performed at a single institution of 7 SNP that occurred in 4045 THA via direct anterior approach and 10 SNP in 8854 THA via posterior approach, being operated between 01 January 2017 and 12 December 2021. SNP patients were matched 1:5 to patients without SNP. Medical records were reviewed for demographics including age, gender, body mass index (BMI), comorbidities, and preoperative indication. Additional workup of SNP patients including advanced imaging and reoperation were documented. Recovery grades were assigned to all SNP patients at most recent clinical follow-up. 5 of the SNP were complete and 12 partial. They occurred as frequently with the direct anterior (0.17%) and posterior approach (0.11%, p = 0.5). The presence of femur cables and reoperations were associated with SNP (p = 0.04 and p = 0.002, respecitvely). Age, gender, BMI, comorbidities, and surgical indication had no effect on SNP. 4 of the 17 affected patients had almost complete recovery at latest follow-up. The incidence of SNP was similar in direct anterior and posterior approach. Surgeons should counsel patients regarding the risks of SNP regardless of the used approach.

An anatomic consideration of the femoral nerve during direct anterior hip approach: A cadaveric study.

This study aimed to investigate the distance and correlation between the anatomy of the anterior side of the hip joint and the femoral nerve. Using ten fresh-frozen cadavers with twenty hip joints. We dissected and marked the femoral nerve in the inguinal area. Employing the direct anterior approach, we identified and marked study points, including the superior and inferior points of the anterior rim of the acetabulum, ¼ point, half point, and ¾ point along an imagined line connecting the formers, the inferomedial and mid aspect of the femoral neck, and the soft spot. Coronal plane measurements gauged the distance between these points and the femoral nerve. The collected data were analyzed to assess the distance and correlation. In the coronal plane, the median distance between the inferior point of the anterior rim of the acetabulum and the femoral nerve was 0 millimeters (interquartile range [IQR] 0-0). Likewise, the median distance between the mid aspect of the medial side of the femoral neck and the femoral nerve was 0 millimeters (IQR 0-0). Additionally, the mean distance between the soft spot and the femoral nerve was 1.18cm (SD 0.63). Surgeons approaching the hip joint via the direct anterior approach should be cautious at the inferior point of the anterior rim of the acetabulum and the mid aspect of the femoral neck. The soft spot at the anterior rim of the acetabulum remains safe from direct injury when surgeons use the correct technique during anterior retractor insertion.

Is AI 3D-printed PSI an accurate option for patients with developmental dysplasia of the hip undergoing THA?

BackgroundIn traditional surgical procedures, significant discrepancies are often observed between the pre-planned templated implant sizes and the actual sizes used, particularly in patients with congenital hip dysplasia. These discrepancies arise not only in preoperative planning but also in the precision of implant placement, especially concerning the acetabular component. Our study aims to enhance the accuracy of implant placement during Total Hip Arthroplasty (THA) by integrating AI-enhanced preoperative planning with Patient-Specific Instrumentation (PSI). We also seek to assess the accuracy and clinical outcomes of the AI-PSI (AIPSI) group in comparison to a manual control group.MethodsThis study included 60 patients diagnosed with congenital hip dysplasia, randomly assigned to either the AIPSI or manual group, with 30 patients in each. No significant demographic differences between were noted the two groups. A direct anterior surgical approach was employed. Postoperative assessments included X-rays and CT scans to measure parameters such as the acetabular cup anteversion angle, acetabular cup inclination angle, femoral stem anteversion angle, femoral offset, and leg length discrepancy. Functional scores were recorded at 3 days, 1 week, 4 weeks, and 12 weeks post-surgery. Data analysis was conducted using SPSS version 22.0, with the significance level was set at α = 0.05.Results and conclusionThe AIPSI group demonstrated greater prosthesis placement accuracy. With the aid of PSI, AI-planned THA surgery provides surgeons with enhanced precision in prosthesis positioning. This approach potentially offers greater insights and guidelines for managing more complex anatomical variations or cases.

Current perspectives of south african orthopaedic surgeons to the direct anterior approach in total hip arthroplasty

Background: Despite the global increase in popularity for the use of the Direct Anterior Approach (DAA) for Total Hip Arthroplasty (THA), the current beliefs and reasons for its use and disuse amongst South African orthopaedic surgeons is not well understood. Objective: To determine the perspectives regarding DAA compared to other surgical approaches to THA. Methods: We conducted an anonymous online survey sent to all current members of the South African Orthopedic Association (SAOA). Results: The response rate was 24.25% (n=194). There were 76 (39.18%) respondents that have performed DAA (DAA Performers) and 118 (60.82%) that have never performed DAA (DAA nonperformers). A proportion of 50% and 11.84% of DAA performers were between 30 to 45 years and older than 60 years of age, respectively (p<0.000). The DAA is the preferred approach to THA for 36.84% (n=28) of DAA performers, whilst 63.16% (n=48) prefer an alternative approach. Both DAA performers who prefer DAA and those who prefer alternative approaches consider DAA more satisfactory for length of hospital stay (p<0.000) and short-term functional outcomes (p=0.002) compared to other surgical approaches. For DAA non-performers, the primary reasons for not performing DAA THA were inexperience in surgical technique (72.09%), increased operative time (12.79%), unsatisfactory outcomes (27.91%) and learning curve (67.44%). There were 5 (18.52%) and 30 (70.33%) surgeons who have been in clinical practice for more than 10 years that do and do not intend to use DAA in the future, respectively (p<0.000). Conclusion: The trends of the adoption of the DAA by South African orthopaedic surgeons show increasing popularity, similar to patterns seen in the United Kingdom and the United States of America. Younger surgeons are more likely to perform the DAA THA whilst more experienced surgeons are less likely to deviate from their current standard of practice.

Clinical outcomes following direct anterior approach during total hip arthroplasty without hip extension: a retrospective comparative study

BackgroundTraditional total hip arthroplasty (THA) using the direct anterior approach (DAA) requires a hip extension. This study aimed to compare the clinical outcomes of patients undergoing THA with DAA using either the no hip extension (NHE) or the traditional hip extension (THE) strategy.MethodsA retrospective analysis of demographics, clinical and radiological outcomes, and occurrence of complications was performed using data from 123 patients treated between January 2020 and November 2021. The patients were categorised into two groups: NHE (84 patients) and THE (39 patients).ResultsThe NHE group exhibited shorter operative time and had more male participants with higher ages. Comparable outcomes were observed in the visual analogue scale, Harris Hip, and Oxford Hip scores at the final follow-up. Furthermore, complications were observed in the NHE and THE groups, including two and one greater trochanteric fractures and three and one transfusions, respectively.ConclusionsCompared to the THE, employing the NHE strategy during THA with DAA in elderly and young female patients resulted in comparable clinical outcomes with several advantages, such as favourable surgical time. The NHE method also exhibited good safety and effectiveness. Therefore, the NHE strategy may be a favourable option for elderly and young female patients.

Application direct anterior approach in pediatric femoral head and neck lesions

BackgroundFemoral neck is one of the high-risk areas for benign tumors and tumor-like lesions. Small range of lesions may also lead to pathological fracture, femoral head necrosis and other serious problems.PurposeTo investigate a new minimally invasive surgical approach to resect femoral head and neck lesions in children.Patients and methodsRetrospective study of 20 patients with femoral neck and femoral head lesions from February 2019 to March 2023 in our hospital. Among them, 14 were boys and 6 were girls, 17 were femoral neck lesions and 3 were femoral head lesions. The age of the patients ranged from 3.2 to 12.6 years, with a mean of 7.1 years. The patients were divided into group A and group B according to different surgical approaches; group A used the Smith-Peterson approach, Watson-Jones approach or surgical dislocation approach and group B used the DAA. Intra-operatively, incision length, operative time and blood loss were recorded in both groups. Group A consisted of 1 femoral head lesion and 8 femoral neck lesions, including 5 cases of bone cyst and 4 cases of eosinophilic granuloma. Group B consisted of 2 femoral head lesion and 9 femoral neck lesions. A total of 11 patients with different types of disease were included in group B, including bone cysts (3 cases), aneurysmal bone cysts (1 case), eosinophilic granulomas (6 cases), Kaposi's sarcoma (1 case).ResultsThe two groups of patients differed in terms of incision length (P < 0.05), operative blood loss (P < 0.05) and operative time (P < 0.05). At 6–48 months post-operatively, there were no significant differences in function and all patients had good hip function.ConclusionThe direct anterior approach is effective for resection of paediatric femoral head and neck lesions. It provides clear exposure of the surgical site, minimal trauma and does not compromise the integrity of the anterior musculature.Level of evidence: III.

Evaluation of an Initial Robotic-Assisted Direct Anterior Approach Cohort Receiving a New Short Metaphyseal Filling Collared Femoral Implant.

Shorter, metaphyseal-filling collared stems have become popular with the direct anterior approach (DAA), based on their ease of broaching and insertion through less invasive surgical exposures. To aid with the DAA, robotic-assisted technology provides three-dimensional computed tomography (CT) preoperative planning and intraoperative guidance to accurately assess stem version. With other femoral stems, this has been shown to provide more accurate implant planning and improved patient outcomes. The purpose of this study was to understand femoral stem placement predictability and patient outcomes for a newly designed metaphyseal-filling collared stem system through a DAA in combination with a robotic-assisted system during a single surgeon's initial cases. A single high-volume surgeon, experienced with robotic-assisted DAA total hip arthroplasty (THA), adopted the use of a metaphyseal-filling collared stem. Intraoperative data and patient outcomes up to six months postoperative were collected prospectively during the surgeon's first 123 cases. Student's t-tests (α=0.05) were used for statistical comparisons. Intraoperative and radiographic assessments were performed for all 123 cases. The estimated version with neck-cut view of the robotic-assisted system was 13.81 ± 3.81°. The final version measurement captured with the robotic-assisted system was 16.56 ± 6.61°. The difference between the estimated version and robotic-assisted measured version was, on average, 2.68 ± 5.7° (p<0.001). The femoral stem sat at the level of the calcar in all but five cases. There were no intraoperative or postoperative periprosthetic fractures. Patients reported significant improvements in reduced Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR), Patient-Reported Outcomes Measurement Information System (PROMIS 10), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores throughout their six-month recovery process with no patients reporting a periprosthetic joint infection, fracture, or dislocation. The use of a metaphyseal-filling collared stem with robotic-assisted DAA resulted in adequate stem version when assessed visually and with CT scan assessments. Version estimation values were improved upon over visual assessments when using the robotic system that maps out the proximal femur and the improvement was also demonstrated when compared to the prior literature. This may also be related to the stem's collar providing a visual guide during stem placement posterior fill of this triple-tapered stem design. Although further follow up is needed to assess longer-term outcomes, at six months postoperatively, patients had significant improvements in patient-reported outcomes with all patients reporting minimal to no restrictions with their THA.

Can Robotic-Arm Assistance Decrease Iatrogenic Soft-Tissue Damage During Direct Anterior Total Hip Arthroplasty?

Manual techniques for total hip arthroplasty (THA) have been widely utilized and proven to be clinically successful. However, the use of advanced computed tomography (CT) scan-based planning and haptically-bounded reamers in robotic-arm assisted total hip arthroplasty (RTHA) holds promise for potentially limiting surrounding soft-tissue damage. This cadaver-based study aimed to compare the extent of soft-tissue damage between a robotic-arm assisted, haptically-guided THA (RTHA) and a manual, fluoroscopic-guided THA (MTHA) direct anterior approach. There were six fresh-frozen torso-to-toe cadaver specimens included, with two surgeons each performing three RTHA and three MTHA procedures. One hip underwent an RTHA and the other hip received an MTHA in each cadaver. Postoperatively, one additional surgeon, blinded to the procedures, assessed and graded damage to nine key anatomical structures using a 1 to 4 grading scale: (1) complete soft-tissue preservation to <5% of damage; (2) 6 to 25% of damage; (3) 26 to 75% of damage; and (4) 76 to 100% of damage. Kruskal-Wallis hypothesis tests were used to compare soft-tissue damage between RTHA and MTHA cases and adjusted for ties. Pooled analysis of the gluteus minimus, sartorius, tensor fascia lata, and vastus lateralis muscle grades demonstrated that cadaver specimens who underwent RTHA underwent less damage to these structures than following MTHA (median, IQR: 1.0, 1.0 to 2.0 vs. 3.0, 2.0 to 3.0; p=0.003). Pooled analysis of the calculated volumetric damage (mm3) for the gluteus minimus, sartorius, tensor fascia lata, and vastus lateralis muscles demonstrated that the cadaver specimens that underwent RTHA underwent less damage to these structures than those that followed MTHA (median, IQR: 23, 2 to 586 vs. 216, 58 to 3,050; p=0.037). This cadaver-based study suggests that utilizing RTHA may lead to reduced soft-tissue damage compared with MTHA, likely due to enhanced preoperative planning with robotic-arm assisted software, real-time intraoperative feedback, haptically-bounded reamer usage, reduced surgical steps, as well as ease of use with reaming. These findings should be carefully considered when evaluating the utilization of robotic-arm assisted THA in practice.

Implementation of the Fast-track Protocol for Total Hip Arthroplasty in a Public Hospital in the State of São Paulo - Brazil.

Objective Evaluate the results of the implementation of the Fast Track Protocol (FTP), a medical practice based on scientific evidence, for elective total hip arthroplasty surgery, mainly comparing the National Average Hospital Admission Rate of 7.1 days. Methods 98 patients who underwent elective total hip arthroplasty surgery via the direct anterior approach, anterolateral approach and posterior approach were included in the FTP from December 2018 to March 2020, being followed up preoperatively, intraoperatively and immediately postoperatively. Results The average length of hospital stay was 2.8 days, being 2.1 days for the direct anterior approach, 3.0 days for the anterolateral access approach and 4.1 days for the posterior access approach. The average surgery time was 90 minutes, 19 (19.39%) of the patients were referred to the ICU in the postoperative period, however, none of them underwent surgery using the direct anterior approach. We had no cases of deep vein thrombosis (DVT), pulmonary embolism (PTE) or neurological injury, 19 (19.39%) patients had postoperative bleeding requiring dressing change, 4 (4.08%) needed blood transfusion, 2 (2.04%) patients had implant instability, 1 (1.02%) patient had a fracture during surgery and 1 (1.02%) patient died of cardiac complications. Conclusion FTP may be a viable alternative to reduce the length of stay and immediate postoperative complications for elective total hip arthroplasty surgery decreasing the length of stay of patients by 2 to 3 times when compared to the national average of 7.1 days.

Mid-term results of cemented hip arthroplasties through the direct anterior approach in the lateral decubitus position: a retrospective cohort study

BackgroundReports show a high complication rate when starting with the Direct Anterior Approach (DAA) in a supine position for hip arthroplasty. The DAA with the patient in lateral decubitus position may avoid this problem because it supposedly provides better visibility, especially on the femoral side. However, this approach did show a rather high complication rate during the adoption of the approach at 1 year follow up in our previous report. We were interested what the overall 7 year survival estimate would be and whether improvement could be seen with growing experience.MethodsA cohort of patients undergoing total hip arthroplasty right from the start of applying the DAA in lateral decubitus position was analysed.ResultsIn total 175 hip prostheses (162 patients) were evaluated. The 7-year survival estimate was 95.1%, 95 CI: 91.8–98.4%. In 6 of 8 revisions there was aseptic loosening of the stem. By dividing the cohort into 3 consecutive groups in time we did not see a significantly improving revision rate.ConclusionsIn our experience, the adoption of the direct anterior approach in lateral decubitus position caused a relatively low 7-year survival estimate without an apparent decrease with growing experience, however given the low number of cases further research is needed to investigate the long-term risk of adopting a new approach.

Rapid Return to Braking After Anterior and Posterior Approach Total Hip Arthroplasty.

Little is known about the effect of surgical approach on return to braking after total hip arthroplasty (THA), and few studies have investigated braking after THA with modern surgical techniques and rehabilitation protocols. In a prospective comparative design, we enrolled 65 patients who received right-sided primary THA at our institution from April 2018 through March 2020, 34 with a direct anterior approach (DAA) and 31 with a posterior approach (PA). Braking tests measuring brake reaction time (BRT) and brake pedal depression (BPD) were administered to patients preoperatively and at 1, 2, and 4 weeks postoperatively using a realistic driving simulator. BRT and BPD were compared between groups and preoperatively versus postoperatively using mixed-effects models. Preoperative BRT averaged 638 msec in the DAA group and 604 msec in the PA group (P = 0.31). At 1 week postoperatively, the DAA group had significantly prolonged BRT compared with preoperatively (694 msec, P = 0.02). No significant difference was observed in the PA group (633 msec, P = 0.31). Both groups had returned to baseline by 2 weeks, and both had significantly faster BRT at 4 weeks compared with preoperatively (583 msec for DAA, P = 0.01; 537 msec for PA, P < 0.001). BPD was similar between groups, and there were no significant differences between preoperative and postoperative BPD at any time point. With modern surgical techniques, BRT after right-sided THA returns to baseline levels approximately 2 weeks after surgery. There seems to be a quicker return to preoperative BRT observed in patients with a PA.

Characteristics and Quality of Online Searches for Direct Anterior Versus Posterior Approach for Total Hip Arthroplasty

BackgroundOnline resources are important for patient self-education and reflect public interest. We described commonly asked questions regarding the direct anterior versus posterior approach (DAA, PA) to total hip arthroplasty (THA) and the quality of associated websites. MethodsWe extracted the top 200 questions and websites in Google’s “People Also Ask” section for 8 queries on January 8, 2023, and grouped websites and questions into DAA, PA, or comparison. Questions were categorized using Rothwell’s classification (fact, policy, value) and THA-relevant subtopics. Websites were evaluated by information source, Journal of the American Medical Association Benchmark Criteria (credibility), DISCERN survey (information quality), and readability. ResultsWe included 429 question/website combinations (questions: 52.2% DAA, 21.2% PA, 26.6% comparison; websites: 39.0% DAA, 11.0% PA, 9.6% comparison). Per Rothwell’s classification, 56.2% of questions were fact, 31.7% value, 10.0% policy, and 2.1% unrelated. The THA-specific question subtopics differed between DAA and PA (P < .001), specifically for recovery timeline (DAA 20.5%, PA 37.4%), indications/management (DAA 13.4%, PA 1.1%), and technical details (DAA 13.8%, PA 5.5%). Information sources differed between DAA (61.7% medical practice/surgeon) and PA websites (44.7% government; P < .001). The median Journal of the American Medical Association Benchmark score was 1 (limited credibility, interquartile range 1 to 2), with the lowest scores for DAA websites (P < .001). The median DISCERN score was 55 (“good” quality, interquartile range 43 to 65), with the highest scores for comparison websites (P < .001). Median Flesch-Kincaid Grade Level scores were 12th grade level for both DAA and PA (P = .94). ConclusionsPatients’ informational interests can guide counseling. Internet searches that explicitly compare THA approaches yielded websites that provide higher-quality information. Providers may also advise patients that physician websites and websites only describing the DAA may have less balanced perspectives, and limited information regarding surgical approaches is available from social media resources.

Traumatic Floating Total Hip Arthroplasty: A Case Report.

A 58-year-old woman with medical history of a left total hip arthroplasty performed by the direct anterior (DA) approach 2 years prior presented with left hip pain. She was found to have sustained a transverse Vancouver C periprosthetic femur fracture and an unstable periprosthetic pelvic fracture. This patient's case represents a previously not reported injury about a total hip arthroplasty-with disruption distal to the femoral implant and proximal to the acetabular implant, with the implant-to-bone interface unaffected. This case may guide future treatment of similar injuries.

Surgical Approach and Body Mass Index Impact Risk of Wound Complications Following Total Hip Arthroplasty

BackgroundPrevious studies have suggested that wound complications may differ by surgical approach after total hip arthroplasty (THA), with particular attention toward the direct anterior approach (DAA). However, there is a paucity of data documenting wound complication rates by surgical approach and the impact of concomitant patient factors, namely body mass index (BMI). This investigation sought to determine the rates of wound complications by surgical approach and identify BMI thresholds that portend differential risk. MethodsThis multicenter study retrospectively evaluated all primary THA patients from 2010 to 2023. Patients were classified by skin incision as having a laterally based approach (posterior or lateral approach) or DAA (longitudinal incision). We identified 17,111 patients who had 11,585 laterally based (68%) and 5,526 (32%) DAA THAs. The mean age was 65 years (range, 18 to 100), 8,945 patients (52%) were women, and the mean BMI was 30 (range, 14 to 79). Logistic regression and cut-point analyses were performed to identify an optimal BMI cutoff, overall and by approach, with respect to the risk of wound complications at 90 days. ResultsThe 90-day risk of wound complications was higher in the DAA group versus the laterally based group, with an absolute risk of 3.6% versus 2.6% and a multivariable adjusted odds ratio of 1.5 (P < .001). Cut-point analyses demonstrated that the risk of wound complications increased steadily for both approaches, but most markedly above a BMI of 33. ConclusionsWound complications were higher after longitudinal incision DAA THA compared to laterally based approaches, with a 1% higher absolute risk and an adjusted odds ratio of 1.5. Furthermore, BMI was an independent risk factor for wound complications regardless of surgical approach, with an optimal cut-point BMI of 33 for both approaches. These data can be used by surgeons to help consider the risks and benefits of approach selection. Level of EvidenceLevel III.

Contribution of the Medial Iliofemoral Ligament to Hip Stability After Total Hip Arthroplasty Through the Direct Anterior Approach

BackgroundDislocation after total hip arthroplasty (THA) is a primary reason for THA revision. During THA through the direct anterior approach (DAA), the iliofemoral ligament, which provides the main resistance to external rotation (ER) of the hip, is commonly partially transected. We asked: (1) what is the contribution of the medial iliofemoral ligament to resisting ER after DAA THA? and (2) how much resistance to ER can be restored by repairing the ligament? MethodsA fellowship-trained surgeon performed DAA THA on 9 cadaveric specimens. The specimens were computed tomography scanned before and after implantation. Prior to testing, the ER range of motion of each specimen to impingement in neutral and 10° of extension was computationally predicted. Each specimen was tested on a 6-degrees-of-freedom robotic manipulator. The pelvis was placed in neutral and 10° of extension. The femur was externally rotated until it reached the specimen’s impingement target. Total ER torque was recorded with the medial iliofemoral ligament intact, after transecting the ligament, and after repair. Torque at extremes of motion was calculated for each condition. To isolate the contribution of the native ligament, the torque for the transected state was subtracted from both the native and repaired conditions. ResultsThe medial iliofemoral ligament contributed an average of 68% (range, 34 to 87) of the total torque at the extreme of motion in neutral and 80% (58 to 97) in 10⁰ of extension. The repaired ligament contributed 17% (1 to 54) of the total torque at the extreme of motion in neutral and 14% (5 to 38) in 10⁰ of extension, restoring on average 18 to 25% of the native resistance against ER. ConclusionsThe medial iliofemoral ligament was an important contributor to the hip torque at the extreme of motion during ER. Repairing the ligament restored a fraction of its ability to generate torque to resist ER.

Functional Acetabular Component Positioning During Direct Anterior Approach Hip Arthroplasty Using a Novel Three-Dimensional Virtual Mesh Imaging System With Fluoroscopy

BackgroundOptimal position of total hip arthroplasty (THA) components is critical for joint mechanics and stability. Acetabular component positioning during supine surgery in direct anterior approach (DAA) THA may be different in the standing position postoperatively, which traditional fluoroscopy is unable to predict. A novel 3-dimensional (3D) image analysis technology (IAT) that uses artificial intelligence to measure the tilt and rotation of the pelvis has enabled prediction of component positioning from supine to standing. The purpose of this study was to compare intraoperative fluoroscopy, non–3D-IAT, and 3D-IAT with postoperative standing radiographs to assess the accuracy of component positioning. MethodsFrom 2022 to 2023, 30 consecutive patients (86.6% women, mean age 59 [range, 55 to 67]) undergoing primary DAA THA with the use of the 3D-IAT were identified. A separate cohort of 148 patients from 2020 to 2021 (85% women, mean age 65 [range, 55 to 69]) who underwent DAA THA with non–3D-IAT was used for comparison. Leg length discrepancy (LLD), cup anteversion, and inclination were manually measured on intraoperative fluoroscopic images and digitally measured using IAT. Follow-up evaluation occurred at 1 month with standing pelvis radiographs measured using Ein Bild Röntgen Analyze–Cup software. Measurements were compared via Wilcoxon signed rank tests where P ≤ .05 indicates significantly different measurements. ResultsMedian LLD, inclination, and anteversion measurements via non–3D-IAT and fluoroscopy were significantly different compared to postoperative standing radiographs (P < .001). The 3D-IAT more accurately predicted LLD, abduction, and anteversion, with values not significantly different from postoperative standing measurements (P = .23, P = .93, and P = .36, respectively). ConclusionsThe use of the 3D-IAT during DAA THA allowed for the more accurate prediction of acetabular component position in the standing position postoperatively.

Evaluation of Outcome after Total Hip Arthroplasty for Femoral Neck Fracture: Which Factors Are Relevant for Better Results?

Background: Femoral neck fractures (FNFs) are frequent orthopedic injuries in elderly patients. Despite improvements in clinical monitoring and advances in surgical procedures, 1-year mortality remains between 15% and 30%. The aim of this study is to identify variables that lead to better outcomes in patients treated with total hip arthroplasty (THA) for FNFs. Methods: All patients who underwent cementless THA for FNF from January 2018 to December 2022 were identified. Patients aged more than 80 years old and with other post-traumatic lesions were excluded. Patient data and demographic characteristics were collected. The following data were also registered: time trauma/surgery, surgical approach, operative time, intraoperative complications, surgeon arthroplasty-trained or not, and anesthesia type. In order to search for any predictive factors of better short- and long-term outcomes, we performed different logistic regression analyses. Results: A total of 92 patients were included. From multivariable logistic regression models, we derived that a direct anterior surgical approach and an American Society of Anesthesiologists (ASA) classification < 3 can predict improved short-term outcomes. Moreover, THAs performed by surgeons with specific training in arthroplasty have a lower probability of revision at 1 year. Mortality at 1 year was ultimately influenced by the ASA classification. Conclusions: A direct anterior approach and specific arthroplasty training of the surgeon appear to be able to improve the short- and long-term follow-up of THA after FNF.