Implant Survival After Minimally Invasive Anterior or Anterolateral Vs. Conventional Posterior or Direct Lateral Approach: An Analysis of 21,860 Total Hip Arthroplasties from the Norwegian Arthroplasty Register (2008 to 2013)

Articulating Materials Are Determinants of Survivorship of Hip Arthroplasties Performed for Nontraumatic Osteonecrosis of the Femoral Head

A nationwide multicenter follow-up cohort study of hip-replacement arthroplasties performed for nontraumatic osteonecrosis of the femoral head (ONFH) was conducted to clarify factors associated with need for reoperation. We analyzed 7393 arthroplasties including 6284 total hip arthroplasties (THAs), 886 bipolar hemiarthroplasties (BPs), 188 total resurfacing arthroplasties, and 35 hemi-resurfacing arthroplasties (hRSs). The identified risk factors were combined systemic steroid use and excessive alcohol consumption (both ONFH-associated factors), a lateral approach, alumina BPs (aBPs), and hRSs, which were reported previously. The present study performed further analyses separately for THAs and BPs to clarify risk factors in each surgical group. A Cox proportional-hazard model identified the following risk factors: the acetabular-articulating materials of conventional polyethylene (cPE) and metal in the THAs and both ONFH-associated factors, minimum-incision surgery (MIS), and aBPs in the BPs. The risk factors were specific to each surgical group. In the ONFH patients, when performing THA, cPE and metal are not recommended as the acetabular-articulating material. When performing BP, patients with both ONFH-associated factors should be treated carefully, and the employment of MIS and use of aBP are not good strategies.

Comparative analysis of patient-reported outcomes in total knee arthroplasty and total hip arthroplasty: adjusting for demographic influences

PURPOSE

Total knee arthroplasty (TKA) has consistently demonstrated lower patient satisfaction compared to total hip arthroplasty (THA). However, prior investigations failed to account for the patients' demographic characteristics. This study aimed to conduct a comparative analysis of patient-reported outcomes between TKA and THA while adjusting for patient background.

METHODS

A total of 326 primary TKAs and 259 THAs conducted at a single center were assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores preoperatively and at 3 months, 1 year, and 2 years postoperatively. Notably, TKA patients exhibited advanced age and higher body mass index (BMI) than their THA counterparts. To mitigate the impact of these differences, we employed propensity score-matched data, adjusting for background characteristics such as age, gender, BMI, and diagnosis.

RESULTS

THA consistently demonstrated significantly superior WOMAC total, pain, and stiffness scores compared to TKA at 3 months, 1 year, and 2 years postoperatively. Nevertheless, no statistically significant disparity in WOMAC physical function scores was observed between the two groups at 3 months and 1 year postoperatively in the matched data (3 months, p = 0.131; 1 year, p = 0.269).

CONCLUSION

In contrast to earlier findings, our analysis of propensity score-matched data revealed no significant differences in WOMAC physical function scores between the TKA and THA groups at 3 months and 1 year postoperatively. The distinctive background factors observed in patients undergoing TKA and THA, notably advanced age and higher BMI, coupled with the delayed improvement timeline in TKA's WOMAC scores compared to that of THA, have the potential to impact patient-reported outcomes. Consequently, clinicians should be mindful of the potential impact of patient background on variations in patient-reported outcome measures following total joint arthroplasty.

Is There a Learning Curve for the 5-Year Implant Survival Rate of Total Hip Arthroplasty Using the Direct Anterior Approach With a Traction Table? A Prospective Cohort Study

BACKGROUND

The direct anterior approach (DAA) for total hip arthroplasty (THA) is attracting attention as a minimally invasive surgery, but the learning curve to master this approach is a concern, and its effect on long-term results is unknown. The purpose of this prospective cohort study was to clarify how the learning curve affects the 5-year results of DAA THA with a traction table.

METHODS

Of 402 THA cases using DAA with a mobile traction table and fluoroscopy, 249 cases composed of the first 50 cases for each surgeon were assessed during a learning curve, and 153 cases were evaluated after more than 50 cases of experience.

RESULTS

The 5-year-implant survival rate was 99.2% both during and after the learning curve. The 2-year complication rate in the learning curve group was 8.9 versus 5.9%, which was not statistically significant. The 2-to-5-year complication rates also did not differ between the cohorts (0 versus 0.7%). Both groups demonstrated decreased complication rates when comparing 2-year complications to 2-to-5-year complications. Clinical scores significantly improved by 2 years and were maintained at 5 years in both groups. The cup safe-zone success rates were 96.4% during the learning curve and 98.7% after the learning curve. The stem safe-zone success rates were 97.2% during the learning curve and 96.1% after the learning curve. Surgical time was approximately 20 minutes shorter after the first 50 cases than during the learning curve (70.8 versus 90.6 minutes, P = .001). Intraoperative blood loss was significantly less after the learning curve than during the learning curve.

CONCLUSIONS

This study implies that the learning curve affects perioperative results such as surgical time and intraoperative blood loss, but has little effect on short-term results up to 2 years after surgery and no effect on mid-term results from 2 to 5 years after surgery.

No Difference in Revision Rates or Patient-Reported Outcome Measures Between Surgical Approaches for Total Hip Arthroplasty Performed for Femoral Neck Fracture: An Analysis of 5,025 Primary Total Hip Arthroplasties From the New Zealand Joint Registry

BACKGROUND

Total hip arthroplasty (THA) for femoral neck fracture (FNF) can be performed through different surgical approaches. This study compared the revision rates and patient-reported outcome measures by surgical approach.

METHODS

Data from the New Zealand Joint Registry were analyzed for patients undergoing primary THA for FNF from January 2000 to December 2021. A total of 5,025 THAs were performed for FNF; the lateral approach was used in 2,499 (49.7%), the posterior in 2,255 (44.9%), and the anterior in 271 (4.3%). The primary outcome measure was the all-cause revision rate. Secondary outcome measures included revision rates for: dislocation, aseptic femoral component loosening, periprosthetic fracture, and infection. Oxford Hip Scores (OHS) were also collected. Age, sex, body mass index, American Society of Anesthesiologists score, femoral head size, dual mobility use, femoral fixation, and surgeon experience were assessed as potential confounding variables.

RESULTS

There was no difference in the revision rates between lateral and posterior (P = .156), lateral and anterior (P = .680), or posterior and anterior (P = .714) approaches. There was no difference in the reasons for revision between the lateral and posterior approaches or 6-month OHS (P = .712). There was insufficient data to compare the anterior approach.

CONCLUSIONS

There is no difference in the overall revision rates, reasons for revision, or OHS between the lateral and posterior surgical approaches for THA performed for FNF. Insufficient data on the anterior approach is available for an accurate comparison.

LEVEL OF EVIDENCE

Level III.

Does Approach Matter in Robotic-Assisted Total Hip Arthroplasty? A Comparison of Early Reoperations Between Direct Anterior and Postero-Lateral Approach

BACKGROUND

There is no consensus on whether direct anterior approach (DAA) or postero-lateral approach (PLA) total hip arthroplasty (THA) confers a lower risk of postoperative complications. Robotic assistance in THA results in a more consistently accurate component position compared to manual THA. The objective of this study was to compare rates of dislocation, reoperation, revision, and patient-reported outcome measures between patients undergoing DAA and PLA robotic-assisted primary THA.

METHODS

We identified 2,040 consecutive robotic-assisted primary THAs performed for primary osteoarthritis, using DAA (n = 497) or PLA (n = 1,542) between 2017 and 2020. The mean follow-up was 18 months. Kaplan-Meier analysis estimated survivorship free of dislocation, reoperation, and revision. Achievement of patient acceptable symptom state and minimum clinically important difference were used to compare changes in the Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS JR) and Visual Analog Scale.

RESULTS

Dislocation was rare in this series (14 in 2,040, 0.7%), including 1 of 497 (0.2%) in the DAA cohort and 13 of 1,542 (0.8%) in the PLA cohort (P = .210). There was no difference in 2-year reoperation-free survivorship (97.8 versus 98.6%, P = .59) or revision-free survivorship (98.8 versus 99.0%, P = .87) at any time point. After controlling for age, sex, and body mass index, there was no difference in dislocation, reoperation, or revision. At 6-week follow-up, after controlling for age, sex, and body mass index, patients in the DAA cohort had higher odds of achieving HOOS JR minimum clinically important difference (odds ratio = 2.01, P = .012) and HOOS JR patient acceptable symptom state (odds ratio = 1.72, P = .028). There were no differences in patient-reported outcome measures by 3 months.

CONCLUSIONS

For robotic-assisted primary THA, DAA may confer enhanced early (<6 weeks) functional recovery compared to the PLA, but there was no significant difference in postoperative dislocation, reoperation, or revision rates.

Reverse Fragility Index: Comparing Revision Rates Between Direct Anterior and Other Approaches in Total Hip Arthroplasty. A Systematic Review of Randomized Controlled Trials

BACKGROUND

Despite increasing adoption of the direct anterior (DA) approach in total hip arthroplasty (THA), uncertainty persists regarding its outcomes beyond the 1-year mark in comparison to other approaches. We used the reverse fragility index (RFI) to evaluate the robustness of reported findings in the literature.

METHODS

We conducted a systematic review of randomized controlled trials (RCTs) comparing implant revision rates between DA and other approaches in THA, defined as all those different from DA. Our primary outcome was the RFI, which gauges the number of events needed for a nonsignificant result to become significant, in the revision rate between DA and other approaches. We also calculated the reverse fragility quotient by dividing the RFI by each study's sample size. Median values and interquartile ranges (IQRs) were displayed.

RESULTS

A total of 10 RCTs with a total of 971 patients were included. The median RFI was 5 (IQR, 4 to 5), indicating the study's results would be statistically significant if the outcomes of 5 patients in 1 treatment arm were reversed. The median reverse fragility quotient was 0.049 (IQR, 0.04 to 0.057), indicating that a change of outcome in 4.9% of patients would render the revision rate significant. The median number of patients lost to follow-up was 4 (IQR, 0 to 7). Of the 10 RCTs, 6 had more patients lost to follow-up than their respective RFI values.

CONCLUSIONS

Notable fragility was evidenced in most studies comparing DA to other approaches for THA. Surgeons should not solely rely on the P value to determine clinical significance and instead use multiple metrics.

LEVEL OF EVIDENCE

II.

Patients Requiring Both Total Hip Arthroplasty and Lumbar Spinal Fusion Have Lower Hip Functional Outcome Scores: A Matched Case-Control Study

BACKGROUND

While patients who undergo both lumbar spinal fusion (LSF) and total hip arthroplasty (THA) have increased complication rates compared to patients who have not undergone LSF, there is a paucity of literature evaluating THA functional outcomes in patients with a history of LSF. This study was conducted to determine whether patients undergoing THA with a history of LSF have inferior functional outcomes compared to patients having no history of LSF.

METHODS

A retrospective matched case-control study was conducted at an academic center. Patients who underwent both THA and LSF (cases) were matched with controls who underwent THA without LSF. Inclusion criteria required a minimum of 1-year follow-up for the Hip Disability and Osteoarthritis Outcome Score Joint Replacement [HOOS-JR]. Following propensity matching for age, sex, race, body mass index, and comorbidities, 291 cases and 1,164 controls were included, with no demographic differences.

RESULTS

Patients who underwent both THA and LSF had a significantly lower preoperative HOOS-JR (47 versus 50; P < .001), postoperative HOOS-JR (77 versus 85; P < .001), a significant lower rate of achieving the patient acceptable symptom state (55 versus 67%; P < .001), with no significant difference in delta HOOS-JR (34 versus 34; P = .834). When comparing patients undergoing THA before LSF or LSF before THA, no differences existed for preoperative HOOS-JR (50 versus 47; P = .304), but patients undergoing THA before LSF had lower postoperative HOOS-JR scores (74 versus 81; P = .034), a lower-delta HOOS-JR (27 versus 35; P = .022), and a lower rate of reaching the HOOS-JR minimal clinically important difference (62 versus 76%; P = .031).

CONCLUSIONS

Patients who have a history of LSF experience a similar improvement in hip function when undergoing THA compared to patients who do not have a history of LSF. However, due to lower preoperative function, they may have a lower postoperative functional outcome ceiling. Additionally, patients undergoing THA before LSF have worse hip functional outcomes than patients undergoing LSF before THA.

Instantaneous Generation of Subject-Specific Finite Element Models of the Hip Capsule

Subject-specific hip capsule models could offer insights into impingement and dislocation risk when coupled with computer-aided surgery, but model calibration is time-consuming using traditional techniques. This study developed a framework for instantaneously generating subject-specific finite element (FE) capsule representations from regression models trained with a probabilistic approach. A validated FE model of the implanted hip capsule was evaluated probabilistically to generate a training dataset relating capsule geometry and material properties to hip laxity. Multivariate regression models were trained using 90% of trials to predict capsule properties based on hip laxity and attachment site information. The regression models were validated using the remaining 10% of the training set by comparing differences in hip laxity between the original trials and the regression-derived capsules. Root mean square errors (RMSEs) in laxity predictions ranged from 1.8° to 2.3°, depending on the type of laxity used in the training set. The RMSE, when predicting the laxity measured from five cadaveric specimens with total hip arthroplasty, was 4.5°. Model generation time was reduced from days to milliseconds. The results demonstrated the potential of regression-based training to instantaneously generate subject-specific FE models and have implications for integrating subject-specific capsule models into surgical planning software.

Results of the transition from posterolateral to anterior minimally invasive approach for total hip arthroplasty

BACKGROUND

The anterior minimally invasive (AMI) approach reduces soft tissue damage, risk of dislocation and enhances recovery, but it is associated with certain complications. The aim of this study is to compare the outcomes of patients who underwent total hip arthroplasty (THA) through posterolateral (PL) and AMI approaches performed by the same surgeon, in order to determine the learning curve associated with this new approach.

METHODS

This retrospective cohort study included patients who underwent THA via PL and AMI approach between 2017 and 2022, with a minimum follow-up of 1 year. Hip fracture and oncologic patients were excluded. Demographic variables, functional scores and perioperative complications were assessed. A bivariate analysis was performed to identify differences between groups.

RESULTS

Data of 124 AMI and 120 PL patients were analyzed. Demographic characteristics among groups were homogeneous. Functional outcomes at 3 months were superior for AMI (Oxford: 43 vs. 38; p < 0.05), no dislocations were identified (0% vs. 4.2%; p < 0.05) and no differences in the transfusion rate were found (6.5% AMI vs. 6.7% PL; p = 0.996). Infection rate was 4% for AMI and 3.4% for PL (p = 0.572). Surgical time was shorter for the PL approach, but the median surgical time of the last 25 AMI cases was shorter.

CONCLUSIONS

The AMI approach is an excellent alternative for patients requiring THA. Although surgical time and perioperative bleeding were greater during the learning curve, this approach offers improved functional outcomes and a lower dislocation rate, without significant differences in transfusion and infection outcomes, demonstrating that responsible innovation and safe implementation of new techniques is possible.

Patients Who Have Had Three or More Levels Fused During Lumbar Spinal Fusion Have Worse Functional Outcomes After Total Hip Arthroplasty

BACKGROUND

Lumbar spinal fusion (LSF) and total hip arthroplasty (THA) are commonly performed in patients who have concomitant spine and hip pathology. While patients who have three or more levels fused during LSF have increased postoperative opioid consumption after undergoing THA, it is unknown whether the number of levels fused during LSF affects THA functional outcomes.

METHODS

A retrospective study was conducted at a tertiary academic center for patients who underwent LSF first and then had a primary THA performed with a minimum of one-year follow-up for the Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS-JR). Operative notes were reviewed to determine the number of levels fused during LSF. There were 105 patients who underwent one-level LSF, 55 patients underwent two-level LSF, and 48 patients underwent three-or-more-level LSF. No significant differences existed in age, race, body mass index, and comorbidities between the cohorts.

RESULTS

While preoperative HOOS-JR was similar among the three cohorts, patients who had three-or-more-level LSF had significantly lower HOOS-JR scores than patients who had two-level or one-level LSF (71.4 versus 82.4 versus 78.2; P = .010) and a lower delta HOOS-JR (27.2 versus 39.4 versus 35.9; P = .014). Patients who had three-or-more-level LSF had a significantly lower rate of achieving minimal clinically important difference (61.7% versus 87.2% versus 78.7%; P = .011) and the patient acceptable symptom state (37.5% versus 69.1% versus 59.0%; P = .004) for the HOOS-JR, compared to patients who had two-level or one-level LSF, respectively.

CONCLUSIONS

Surgeons should counsel patients who have had three-or-more-level LSF that they may have a lower rate of hip function improvement and symptom acceptability after THA, compared to patients who have had a less number of levels fused during LSF.

A propensity score-matched analysis on the impact of patient and surgical factors on early periprosthetic joint infection in minimally invasive anterolateral and transgluteal total hip arthroplasty

INTRODUCTION

Increased risk of periprosthetic joint infection (PJI) in minimally invasive (MIS) total hip arthroplasty (THA) is still debated. This study aimed to identify differences in surgical and patient-related risk factors for PJI between an MIS anterolateral approach and transgluteal-modified Hardinge approach.

METHODS

A retrospective cohort of 5315 THAs performed between 2006 and 2019 at a single institution was screened. Short stem THAs performed via an MIS anterolateral approach in the supine position and standard straight stem THAs performed via a transgluteal modified Hardinge approach were included. Propensity score matching was performed to control for selection bias. After matching, 1405 (34.3%) short stem THAs implanted via MIS anterolateral approach and 2687 (65.7%) straight stem THAs implanted via a transgluteal modified Hardinge approach were included. The risk of PJI due to patient-specific and surgical factors was retrospectively analyzed using chi-square test and multivariate regression analysis.

RESULTS

PJI occurred in 1.1% in both MIS anterolateral and transgluteal approach (p = 0.823). Multivariate regression showed an increased infection risk for patients with a BMI between 35 and 39.99 kg/m² (OR 6.696; CI 1.799-24.923; p = 0.005), which could not be demonstrated for transgluteal approach (OR 0.900; CI 0.900-4.144; p = 0.93). A BMI ≥ 40 kg/m² (OR 14.150; CI 2.416-82.879; p = 0.003) was detected as a risk factor for PJI only in anterolateral approach. Increased operation time ≥ 121 min showed a significantly increased risk for PJI in the general cohort (OR 6.989; CI1.286-37.972; p = 0.024).

CONCLUSION

Minimally invasive anterolateral and transgluteal THA show a comparable rate of early PJI within the first year of index surgery. A BMI of ≥ 35 kg/m² was detected as a clear risk factor for infection in the anterolateral approach. Prolonged operation time ≥ 121 min increases the risk of PJI regardless of approach.

Hip dysfunction-related urinary incontinence and total hip arthroplasty with the direct lateral approach

OBJECTIVES

There is a functional relationship between the hip joint and the pelvic floor muscles. In patients with secondary osteoarthritis of the hip, urinary incontinence is also seen. Research has shown that total hip arthroplasty (THA) surgery improves the symptoms of urinary incontinence. This prospective cross-sectional study without a control group was performed on THA candidates with urinary incontinence and secondary osteoarthritis with the aim of investigating the effect of THA with a direct lateral approach and subsequent routine physiotherapy on the symptoms of urinary incontinence.

METHODS

Sampling was performed using a simple method among those referred to orthopedic clinics in the private sector. Data were collected in all patients before and 3 months after THA using demographic, International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and hip range of motion record tables. The results are presented as mean with standard deviation.

RESULTS

In this study, 16 men with a mean age of 76.75 years (±4.65) and 8 women with a mean age of 72.75 years (±7.32) participated. Before THA, stress urinary incontinence (54.16%) and urgency urinary incontinence (20.83%) had the highest frequency. However, after THA, the frequency of stress and urgency urinary incontinence decreased (16.66% and 8.33%, respectively). According to the results of the ICIQ, complete improvement of urinary incontinence symptoms was observed in up to 62.5% of the subjects. After THA, there was a significant difference between the mean total score obtained from the WOMAC questionnaire compared to before surgery. There was a significant improvement in the range of motion of the hip joint in all directions.

CONCLUSIONS

THA and routine hip physiotherapy in patients with urinary incontinence and secondary hip osteoarthritis have a significant positive effect on improving symptoms of urinary incontinence and hip function. In addition, it significantly improves the ICIQ and WOMAC questionnaire scores.

MRI assessment of minimally invasive anterolateral approaches in total hip arthroplasty

INTRODUCTION

Total hip arthroplasty (THA) on a minimally invasive anterolateral (MIAL) approach frequently leads to gluteus minimus and gluteus medius lesions, and sometimes to tensor fasciae latae (TFL) denervation. We therefore developed compensatory strategies, which we assessed on pre- and post-operative MRI: 1) to assess gluteus minimus and gluteus medius fatty infiltration (FI), 2) to assess TFL FI, and 3) to assess FI in the other periarticular muscles.

HYPOTHESIS

The modified MIAL approach reduces the rate of gluteus minimus and gluteus medius lesion.

MATERIALS AND METHODS

A continuous prospective single-surgeon series of THA using a MIAL approach included 25 patients. Femoral implantation was performed with the hip in extension so as to distance the proximal femur from the gluteals, avoiding muscle trauma. The superior gluteal nerve branch in the space between the gluteus medius and TFL, running toward the TFL, was systematically released and protected. MRI was performed preoperatively and at 3 months and 1 year post-surgery. FI was analyzed according to the Goutallier classification in all periarticular muscles.

RESULTS

One patient lacked preoperative MRI and was excluded, leaving 24 patients, for 72 MRIs. In 10/24 patients (41.7%) the gluteus minimus and in 8/24 patients (33.3%) the anterior third of the gluteus medius showed ≥2 grade increase in FI between preoperative and 1-year MRI, with significant increases in both at 3 months (p<0.001) and 1 year (p<0.001). At least a 2 grade increase in FI at 1 year was seen in 1 patient (4.2%) in the TFL, in 2 (8.3%) in the piriformis, and in 1 (4.2%) in the obturator internus. There were no significant differences in FI between preoperative, 3-month or 1-year MRI in any other periarticular muscles.

CONCLUSION

Femoral implantation in hip extension did not reduce the rate of gluteal lesions, which remained frequent. In contrast, release of the superior gluteal nerve branch could be effective in conserving TFL innervation. Some rare lesions of the proximal part of the pelvi-trochanteric muscles were also observed.

LEVEL OF EVIDENCE

IV, Prospective case series.

Cementless total hip arthroplasty with anatomic-shaped implants. Does the minimal invasive anterolateral technique influence the stem position or subsidence in contrast to the standard lateral approach?

INTRODUCTION

Using cementless stems in total hip arthroplasty (THA) has revealed variable results. The risk for early aseptic loosening has been associated to certain surgical approaches and implant designs. This study determines misalignment of collared/collarless stems and the rate of subsidence using the anterolateral approach (ALA) compared to implantations via the direct lateral approach (DLA).

MATERIALS AND METHODS

One hundred consecutive patients underwent primary unilateral THA using the minimal invasive ALA in the lateral decubitus position and were compared to another cohort of 100 patients, treated trough the DLA. Clinical results were noted preoperatively and after 1 year using the WOMAC score. The radiographic evaluation included the stem alignment and subsidence.

RESULTS

Overall, all patients improved in WOMAC from 48.9 points (± 11.4; 21.0-82.0) to 3.1 (± 3.2; 0.0-22.0) (p < 0.001). For DLA and ALA, the stem was placed on average 2.5° in varus to the femoral axis. The mean alignment was about 0.5° more valgus for collarless stems. The mean subsidence in the DLA group was about 0.3 mm higher compared to the ALA group. With collarless implants, the subsidence was about 1.0 mm higher compared to collared implants (p < 0.05), especially in patients with Dorr type B femurs.

CONCLUSIONS

Changing from the DLA to the minimal invasive ALA did not significantly affect the implant position. Misalignment and a potential risk for early aseptic loosening could not be seen. The use of a collared cementless stem seems safe and is likely to prevent a relevant subsidence, even more so in Dorr type B femurs.

LEVEL OF EVIDENCE

III.

Compared learning curves of the direct anterior and anterolateral approach for minimally invasive hip replacement

Minimally invasive hip arthroplasty becomes increasingly popular. It is technically challenging and the approaches used are associated with a considerable learning curve. This nurtures concerns regarding patient safety, surgical training, and cost effectiveness. Consequently, we initiated a study comparing the learning curves of a supervised trainee surgeon utilizing both the anterolateral and direct anterior approach (DAA) when introduced to minimally invasive hip replacement surgery. Outcome measurements included the Harris hip score (HHS), cup inclination and anteversion, offset and leg length, stem placement, surgical time and complications. Time from incision to suture decreased significantly over time but did not differ between both groups. The functional outcomes (HHS) after six weeks and three months were comparable (p=0.069 and 0.557) and within the expected range equalling 90.3 (anterior) and 89.2 (anterolateral) points. With both approaches safe component placement was readily achieved. Both offset and leg length, however, were reconstructed more reliably with the DAA (p=0.02 and 0.001). A higher rate of dislocations was seen with the anterior, more perioperative infections with the anterolateral approach. We suggest that supervision by an experienced surgeon favourably influences the learning curves for both the minimally invasive DAA and anterolateral approach and conclude that the greatest improvement is seen within the first 60 cases.

The influence of anterior and posterior knot placement on hip function after total hip arthroplasty using a modified Dall's approach: a prospective non-randomised comparative study

BACKGROUND

The direct lateral modified Dall's approach for total hip arthroplasty (THA) provides an excellent vision of the hip joint by osteotomising the greater trochanter (GT). A robust method for the reattachment of osteotomised fragments is essential to prevent complications around the GT. Ultra-high molecular weight polyethylene cables are reported to be useful for reattachment; but the optimal suture method of these cables is unknown. The purpose of this study was to investigate the influence of the knot position on hip function after primary THA.

METHODS

In a prospective non-randomised study 216 primary THA were included, being scheduled for an operation with a modified Dall's approach. They were divided into 2 groups, anterior (A) and posterior (P) according to the knot position for the GT. Hip function was assessed using the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), pain visual analogue scale (VAS), satisfaction VAS and Merle d'Aubigne-Postel hip score at 3 and 6 months postoperatively. A logistic regression analysis was used to investigate factors influenced by the knot position.

RESULTS

Patient demographics were comparable between the 2 groups. Differences of the knot position did not affect the radiological failure rate of GT reattachment. Regression analysis showed a significantly positive impact on pain VAS and flexion range at 6 months postoperatively for posterior knot position.

CONCLUSIONS

For the reattachment of osteotomised fragments, the posterior knot may be superior to the anterior knot.

Anterior approach to hip replacement and associated complications: an independent review

BACKGROUND

Direct anterior approach (DAA) to hip replacement is increasingly popular. Despite the well-published benefits of early recovery, the approach can be associated with a number of complications that may be underreported. We aim to report the incidence of some of these complications in a large retrospective case series.

METHODS

270 consecutive DAA hip replacements are studied which are performed by a single high-volume hip surgeon from 2013 to 2015, not including the surgeon's learning curve. Operation and consultation records were screened, and focused questioning via telephone was employed to capture specific complications including dislocations, wound infections, lateral femoral cutaneous nerve (LFCN) injury and revision surgery.

RESULTS

240 of 270 patients or family were contactable. The mean age and body mass index of the cohort was 66 (range 30-89) years and 27 (range 18-40) kg/m2 respectively. The mean follow-up was 3.7 years. Wound issues were encountered in 24 patients (8.8%). There were 9 dislocations (3%). 27 (10%) patients needed revision surgery in the follow-up period. Reasons for revision included leg-length discrepancies, dislocations, ongoing pain and aseptic loosening. 9 (3.4%) patients had to return to operating theatre for reasons other than revision surgery. Symptoms of lateral femoral cutaneous nerve injury was reported by 54 patients (21%).

CONCLUSIONS

While the short-term benefits of DAA have been widely reported, our review shows a relatively high rate of revision surgery. We feel that the enthusiasm for DAA should be tempered until further evidence is available.

Anterolateral minimally invasive hip approach offered faster rehabilitation with lower complication rates compared to the minimally invasive posterior hip approach-a University clinic case control study of 120 cases

INTRODUCTION

The surgical approach used in total hip arthroplasty (THA) has been identified as a factor affecting the outcome. In our University Hospital, the posterior surgical approach is the gold standard. The Rottinger approach is an anterolateral approach which is truly minimally invasive, as it does not vertically cut any muscle fibers. The objective of this study was to determine the difference in surgical outcomes between the posterior hip approach and the Rottinger approach which was newly adopted at our Hospital.

METHODS

In a retrospective study, a total of 120 patients underwent THA; 60 patients using the Rottinger approach by the young consultant surgeon and another 60 patients using the standard posterior approach by the senior orthopaedic surgeon. Patients have been controlled for age, gender, and ASA grades. All preoperative demographic data showed no significant difference between the control and study groups. The following parameters were analyzed: incision length, duration of the surgery, intraoperative blood loss, WOMAC index, Harris Hip Score, range of motion at 3 and 12 months after surgery, time of quitting the crutches, and willingness for the contralateral hip arthroplasty.

RESULTS

WOMAC index, surgical time, and incision lengths have been without significant difference in both approaches. Intraoperative blood loss was significantly lower in the Rottinger group (CI:  - 10.903,  - 0.064). Harris Hip score was significantly higher (CI: 4.564, 12.973) in the Rottinger group at 3 months, but similar (CI:  - 3.484, 2.134) at 12 months follow-up. At 3 months, active flexion and extension were significantly higher in the Rottinger group (CI: 0.595, 8.239; 2.487, 4.480, respectively), and active abduction and passive adduction (CI:  - 5.662,  - 0.338;  - 6.290,  - 1.410, respectively) in the posterior approach group. Patients in the Rottinger approach group on average quit crutches 3 weeks earlier and had no postoperative dislocations compared to 2 dislocations in the control group.

CONCLUSION

The Rottinger approach offered faster rehabilitation with less need for crutches and with lower complication rates.

Low pelvic incidence is a risk factor for intraoperative complications in minimally invasive anterolateral approach for total hip arthroplasty

BACKGROUND

Minimally invasive anterolateral approach (ALA) has gained popularity in recent years as better postoperative functional recovery and lower risk of postoperative dislocation are claimed. However, difficulties for femur exposure and intraoperative complications during femoral canal preparation and component placement have been reported. This study analyses the effect of anatomical factors on difficulties for femoral access and intraoperative complications with a modified minimally invasive ALA.

MATERIAL AND METHODS

310 consecutive patients who had primary unilateral total hip arthroplasty (THA) by single surgeon using same approach and technique, and being suitable for EOS were included. All patients underwent pre- and postoperative standing and sitting full-body EOS acquisitions and pelvic and femoral parameters were measured. All intra- and postoperative complications for femoral preparation and implantation were assessed. Intraoperative complications included femoral fractures and difficulties for femoral exposure.

RESULTS

10 patients (3.2%) had intraoperative femoral fractures (2 greater trochanter, 8 calcar). Difficult access to the proximal femur was reported for 10 other patients (3.2%). Patients with intraoperative complications presented a significantly lower pelvic incidence (PI) than patients without intraoperative complications (mean PI: 39.4° vs. 56.9°, p < 0.001).

CONCLUSIONS

The pelvic incidence can be useful to detect anatomically less favourable patients for THA implantation using ALA.

Direct anterior approach hip arthroplasty: How to reduce complications - A 10-years single center experience and literature review

BACKGROUND

The direct anterior approach for total hip arthroplasty (DAA-THA) is increasing in popularity due to some advantages such as less surgical trauma, minimal dissection of soft tissues, shorter rehabilitation times, faster return to daily activities, lower incidence of dislocation. On the other hand, the literature reports a high rate of intraoperative complications, with many different rates and complication types in the published papers.

AIM

To analyze our complications comparing results with the literature; to report measures that we have taken to reduce complications rate.

METHODS

All DAA-THA patients with one year minimum follow up who were operated at a single high-volume centre, between January 2010 and December 2019 were included in this retrospective study. All surgeries were performed using cementless short anatomical or straight stems and press fit cups. Patients’ follow-up was performed, at 6 wk, 3 mo, then annually post-surgery with clinical and radiological evaluation. Primary outcomes were stem revision for aseptic loosening and all-cause stem revision. Second outcome was intra-operative and post-operative complications identification.

RESULTS

A total of 394 patients underwent DDA-THA from January 2010 and December 2019, for a total of 412 hips; twelve patients lost to follow-up and one patient who died from causes not related to surgery were excluded from the study. The average age at the time of surgery was 61 years (range from 28 to 78 years). Mean follow-up time was 64.8 mo (range 12-120 mo). Seven stems were revised. One cortical perforation, one trochanteric and lateral cortical wall intraoperative fracture, one diaphyseal fracture, three clinically symptomatic early subsidence and one late aseptic loosening. We also observed 3 periprosthetic fractures B1 according to the Vancouver Classification. Other minor complications not requiring stem revision were 5 un-displaced fractures of the calcar region treated with preventive cerclage, one early infection, one case of late posterior dislocation, 18 case of asymptomatic stem subsidence, 6 cases of lateral cutaneous femoral nerve dysesthesia.

CONCLUSION

DAA is associated to good outcomes and lower incidence of dislocation. Complication rate can be reduced by mindful patient selection, thorough preoperative planning, sufficient learning curve and use of intraoperative imaging.

Minimally invasive anterolateral approach versus direct anterior approach total hip arthroplasty in the supine position: a prospective study based on early postoperative outcomes

BACKGROUND

Minimally anterolateral approach (MAA) and direct anterior approach (DAA) have been reported as beneficial for total hip arthroplasty (THA) due to their ability to reduce postoperative pain and lead to quicker rehabilitation by preserving muscle insertions. As there is an ongoing debate on the effect of these two approaches on early postoperative outcomes, this prospective study aimed to assess the difference in early clinical, radiological, and patient-reported outcomes between the two minimally invasive approaches.

METHODS

A total of 98 patients, 50 in the MAA group and 48 in the DAA group, were included in the study. Patients with complete data were evaluated preoperatively and postoperatively at 2, 6, and 12 weeks. Clinical measurements, including the ability to climb stairs and walk, 6-min walk test (6MWT), the Forgotten Joint Scale (FJS-12), Japanese Orthopedic Association (JOA) Hip scores, radiological evaluation, and complications were analyzed.

RESULTS

There were no significant differences in clinical outcomes and implant alignments between MAA and DAA groups. In regards to patient-reported outcomes, the FJS-12 was significantly higher in the MAA group compared to group DAA at 2 and 6 weeks postoperatively. However, there was no significant difference in the FJS-12 between the two groups 12 weeks after surgery. The differences also included shorter operative times (62.4 ± 9.05 min vs. 71 ± 8.01 min), less blood loss (132.6 ± 43.31 ml vs. 159.23 ± 37.25 ml), lower Hb drop (29.56 ± 8.02 g/L vs. 36.4 ± 7.12 g/L), and fewer blood transfusions in the MAA group (4.0% vs. 18.8%). The incidence of the lateral femoral cutaneous nerve (LFCN) neuropraxia after surgery was 7 (14.6%) in the DAA group and 0 in the MAA group. One fracture was found in each group and managed conservatively.

CONCLUSION

MAA and DAA approach yielded excellent and similar early clinical outcomes. However, better patient-reported outcomes could be achieved by MAA THA. The MAA resulted in a safer approach associated with shorter operative times, less blood loss, lower Hb drop, fewer blood transfusions, and LFCN neuropraxia than DAA. A longer follow-up is needed to further examine differences between these procedures.

Early failure of an uncemented femoral stem, as compared to two other stems with similar design, following primary total hip arthroplasty performed with direct anterior approach

INTRODUCTION

An increased risk of early femoral component loosening has been reported using the direct anterior approach (DAA) compared with other common surgical approaches. However, long-term data are scarce. The purpose of this study is: (1) to determine the incidence of early femoral loosening in a high volume, single surgeon's practice utilising the DAA approach; and (2) to examine the effect of stem design and type of coating on aseptic loosening in the early and mid-term postoperative period.

METHODS

A retrospective review of 1650 consecutive patients (1800 hips) who underwent total hip arthroplasty (THA) using the DAA between August 2011 and December 2017 was conducted at our institution. 3 types of uncemented femoral stems (Quadra-S, Avenir, TwinSys), with similar design, but different coating, were implanted. Patients were evaluated clinically and radiologically at 4 weeks, 3 months, 1 year, and annually thereafter.

RESULTS

After a mean follow-up of 46.4 months, the total incidence of revision for aseptic loosening was 0.44% (n = 8). All loose stems were Quadra-S, failing to achieve osseointegration, for an overall incidence of 0.96% (p = 0.002). None of the other stems were loose. Radiolucent lines around the proximal stem portion were visible in 75 Quadra-S stems (4.1%) on radiographs taken at 1 year postoperatively and continued to deteriorate at the latest follow-up.

CONCLUSIONS

In this specific cohort of patients, the increased rate of femoral stem aseptic loosening was implant-related and was attributed only to a specific type of femoral stem (Quadra-S). No relation to other factors was proven suggesting that the surface characteristics of this femoral stem and the lack of bioactive coating are responsible for the observed early femoral failures. These findings should be confirmed by additional registry work and larger population sample sizes are needed to evaluate the prosthesis performance after implantation through the DAA.

How to Prevent Aseptic Loosening in Cementless Arthroplasty: A Review

Aseptic loosening is the main late postoperative complication of cementless total hip arthroplasties (THAs), leading to pain and functional impairment. This article aims to update the orthopedic surgeon on the various methods by which the aseptic loosening rate can be reduced. We performed a systematic review by searching the PubMed database for hip aseptic loosening. We included meta-analysis, randomized controlled trials, reviews, and systematic reviews in the last 10 years, which provided information on techniques that can prevent aseptic loosening in total hip arthroplasty. From a total of 3205 articles identified, 69 articles (2%) met the inclusion criteria, leading to a total of 36 recommendations. A lot of research has been conducted in terms of septic loosening in the last decade. Currently, we have various techniques by which we can reduce the rate of aseptic loosening. Nevertheless, further randomized clinical trials are needed to expand the recommendations for aseptic loosening prevention.

Comparison of the Early Results of Lateral Direct Anterior Approach (L-DAA) and Traditional Posterolateral Approach (PLA) in Hip Arthroplasty

Objective

To evaluate the early results of lateral direct anterior approach (L-DAA) and traditional posterolateral approach (PLA) in hip arthroplasty.

Methods

A total of 24 patients who underwent hip replacement from 2018 to 2021 were divided into PLA group (N = 12) and L-DAA group (N = 12) according to the method of random table number. Outcomes were evaluated between the two groups.

Results

The length of incision was shorter; the amount of bleeding was less in the L-DAA group than that in the PLA group. The visual analogue scale (Vas) pain scores for the L-DAA group were significantly lower than that for the PLA group at 24 h, 72 h, and 1 month after operation, and Harris hip scores in the L-DAA group were significantly high in the PLA group at 1 month after operation. In addition, there are no statistically significant differences in acetabular anteversion, abduction, and angle between the two groups.

Conclusion

L-DAA was superior to PLA for early recovery after hip arthroplasty.

Management of femoral neck fractures with the ALMIS approach in elderly patients: Outcomes compared to posterior approach

INTRODUCTION

Over the last 2 decades, several minimally invasive surgical techniques and approaches have been introduced for hip arthroplasty, including anterolateral minimally invasive surgery (ALMIS) introduced by Röttinger in 2004. As described, this muscle sparing approach promises faster recovery and lower dislocation rates. Although there has been a peaked recent interest in minimally invasive surgery (MIS) hip arthroplasty, few studies support the superiority of ALMIS compared to the more traditional posterior approach. The present study examines the safety and early complications of elderly patients undergoing ALMIS compared to a posterior approach for hemiarthroplasty of displaced femoral neck fractures.

METHODS

In a retrograde level III case-control study, 100 consecutive elderly patients with primary hip arthroplasty were divided into two groups. The first group consisted of 50 consecutive cases operated with the ALMIS approach and the second group of 50 consecutive cases operated through a posterior approach. Operative time, postoperative complication rates, length of hospitalization, blood loss, and leg-length discrepancy, were reviewed retrospectively.

RESULTS

No differences were observed in post-operative complications. Overall, the operative time was significantly greater in the ALMIS group compared to the posterior approach group (75 ± 12 vs 67.5 ± 16 min, respectively; p ≤ 0.01). However, the operating time of the second half of the ALMIS cohort (N = 25), did not differ from the posterior approach group (72.7 ± 10.5 vs 67.5 ± 16, respectively; p = 0.19). Leg length discrepancy was significantly less in the ALMIS group compared to the posterior exposure group (1.5 ± 3.2 vs 3.2 ± 3.3, respectively; P≤0.1).

CONCLUSIONS

The results of the retrograde analysis, although limited in sample size, shows no major differences in ALMIS compared to a more traditional posterior approach in terms of immediate post-operative complications. Although the overall operating time was longer in the patients treated with ALMIS, the second cohort of patients treated with this method had an operating time that was similar to that observed with posterior approach. Leg-length discrepancies were significantly less in patients treated with ALMIS.

How Does Implant Survivorship Vary with Different Corail Femoral Stem Variants? Results of 51,212 Cases with Up to 30 Years Of Follow-up from the Norwegian Arthroplasty Register

BACKGROUND

The Corail® cementless stem (DePuy Synthes) has been used in Norway since 1987 and is one of the most frequently used stems in THA worldwide. Although the published survival results of the standard Corail stem have been good, little is known about the long-term (more than 20 years) survival of other stem design variants. Further, some changes were made to the extramedullary part of the stem in 2003, and the effect of these changes on survival is unknown.

QUESTIONS/PURPOSES

(1) What is the survival up to 30 years of the standard collarless Corail femoral stem, and were extramedullary changes (slimmer, polished and rectangular neck, shorter taper) associated with differences in survivorship? (2) How does the 10-year survival and the risk of revision of other Corail stem variants, including the standard collared stem, coxa vara collared stem, and high offset collarless stem, compare with those of the standard collarless stem? (3) Which factors are associated with an increased risk of revision of the Corail stem, and are there any differences in those factors among the four stem variants?

METHODS

Data for this study were drawn from the Norwegian Arthroplasty Register. Since 1987, THAs have been registered in the Norwegian Arthroplasty Register with completeness of data greater than 97% for primary THAs and 93% for revisions. To study survivorship with up to 30 years of follow-up (1987 to 2018; median 7.7-year follow-up), and to compare the original stem with stems with extramedullary modifications, we included 28,928 standard collarless Corail stems in 24,893 patients (mean age at time of implantation 62 years; 66% [16,525 of 24,893] were women). To compare the newer stem variants with the standard collarless stem (2008 to 2018), we included 20,871 standard collarless, 10,335 standard collared, 6760 coxa vara collared, and 4801 high offset collarless stems. Survival probabilities were estimated using the Kaplan-Meier method with endpoints of stem revision, revision due to aseptic stem loosening, and periprosthetic fracture. The endpoint of all noninfectious causes of THA revision (including cup revision) was additionally analyzed for the long-term comparison. The proportion of patients who died was limited, and there was no difference in death rate between the groups compared. Therefore, we believe that competing events were not likely to influence survivorship estimates to a large degree. To compare different stem variants and evaluate factors that could be associated with the risk of revision, we calculated hazard ratios using Cox regression analyses with adjustments for gender, age group, surgical approach, diagnosis, and stem size.

RESULTS

The 30-year Kaplan-Meier survival of the standard collarless stem was 88.4% (95% confidence interval 85.4% to 91.4%), 93.3% (95% CI 91.1% to 95.5%), and 94.4% (95% CI 92.0% to 96.8%) using stem revision for any noninfectious cause, aseptic loosening, and periprosthetic fracture of the femur as endpoints, respectively. There was no difference in survival between the original stem and the modified stem. The 10-year Kaplan-Meier survivorship free of stem revision (all causes including infection) was 97.6% (95% CI 97.2% to 98.0%) for the standard collarless stem, 99.0% (95% CI 98.8% to 99.2%) for the standard collared stem, 97.3% (95% CI 96.3% to 98.3%) for the coxa vara collared stem, and 95.0% (95% CI 93.6% to 96.4%) for the high offset collarless stem. Compared with the standard collarless stem, the standard collared stem performed better (HR 0.4 [95% CI 0.3 to 0.6]; p < 0.001) and the high offset collarless stem performed more poorly (HR 1.4 [95% CI 1.1 to 1.7]; p = 0.006) with any stem revision as the endpoint, and similar results were found with revision for aseptic stem loosening and periprosthetic fracture as endpoints. Controlling for the noted confounders, the standard collared stem had a lower revision risk. The high offset collarless stem had an increased stem revision risk for any reason (HR 1.4 [95% CI 1.1 to 1.7]; p = 0.006) and aseptic loosening (HR 1.6 [95% CI 1.1 to 2.3]; p = 0.022). Other factors associated with an increased risk of stem revision for all stem variants were being a man (HR 1.7 [95% CI 1.4 to 2.0]; p < 0.001), age 70 to 79 years and 80 years and older compared with the age group of 50 to 59 years (HR 1.6 [95% CI 1.2 to 2.0]; p < 0.001 and HR 1.9 [95% CI 1.4 to 2.6]; p < 0.001, respectively), the anterior approaches (direct anterior Smith-Petersen and anterolateral Watson-Jones combined) compared with the posterior approach (HR 1.4 [95% CI 1.1 to 1.7]; p = 0.005), as well as a preoperative nonosteoarthritis diagnosis (HR 1.3 [95% CI 1.0 to 1.6]; p = 0.02) and small stem sizes (sizes 8-11) compared with the medium sizes (sizes 12-15) (HR 1.4 [95% CI 1.1 to 1.6]; p = 0.001). The very small sizes (8 and 9) were associated with a 2.0 times higher risk of revision (95%. CI 1.4 to 2.6; p < 0.01) compared with all other sizes combined.

CONCLUSION

When using the uncemented Corail stem, surgeons can expect good results with up to 30 years of follow-up. Our results should be generalizable to the typical surgeon at the average hospital in a comparable setting. From our results, using a collared variant would be preferable to a collarless one. Due to an increased risk of periprosthetic fracture, caution with the use of the uncemented Corail stem in patients older than 70 years, especially in women, is warranted. Poorer stem survival should also be expected with the use of small stem sizes. The risk of periprosthetic fractures for the Corail uncemented stem versus cemented stems in different age categories has not been extensively examined, nor has the use of a collar for different age groups and genders, and both should be subjects for further investigation.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Comparisons between Direct Anterior Approach and Lateral Approach for Primary Total Hip Arthroplasty in Postoperative Orthopaedic Complications: A Systematic Review and Meta-Analysis

The direct anterior approach (DAA) are attracting increasing attention from orthopedic arthroplasty surgeons, due to the less blood loss, mild soft tissue invasion, rapid rehabilitation and shorter length of stay. However, the longer learning curve in DAA can give rise to several complications, such as intraoperative femoral fracture, lateral femoral cutaneous nerve injury, wound-healing problem, premature revision and so on. This meta-analysis was performed to compare the rate of postoperative orthopedic complications between the DAA and the lateral approach (LA). All studies involving the comparison of postoperative orthopedic complications after THA between the DAA and LA group were searched in 7 databases prior to October 2020. The odds ratio (OR) with the 95% confidence intervals (CI) for each outcome was calculated by using the RevMan 5.3. The methodological bias of included studies was evaluated and the potential heterogeneity sources were analyzed. Thirteen comparative studies including a total of 24853 hips (9575 hips in the DAA group and 15278 hips in the LA group) were eligible for this meta-analysis. There was no significant difference in the rate of surgical site infection [2.59% vs 2.14% (OR = 0.98; 95% CI: 0.59-1.61, P = 0.93)], heterotopic ossification [12.16% vs 26.47% (OR = 0.46; 95% CI: 0.20-1.07, P = 0.07)] and reoperation [2.70% and 2.11% respectively (OR = 0.93; 95% CI: 0.68-1.26, P = 0.64)] between the DAA and LA groups. Although a lower rate in prosthesis malposition [36.19% vs 54.86% (OR = 0.50; 95% CI: 0.35-0.73, P = 0.0003)], leg length discrepancy [1.87% vs 2.37% (OR = 2.35; 95% CI: 1.30-4.25, P = 0.005)] and Trendelenburg gait [1.68% vs 4.78% (OR = 0.29; 95% CI: 0.13-0.65, P = 0.003)] was observed in the DAA group, a higher rate in dislocation [0.77% vs 0.18% (OR = 3.73; 95% CI: 2.35-5.94, P< 0.00001)], periprosthetic fracture [1.05% vs 0.41% (OR = 2.38; 95% CI: 1.58-3.58, P< 0.0001)], prosthesis loosening [0.61% vs 0.37% (OR = 1.66; 95% CI: 1.05-2.62, P = 0.03)] and nerve injury [0.95% vs 0% (OR = 7.12; 95% CI: 1.66-30.48, P = 0.008)] was found in the DAA group. This meta-analysis demonstrated several evidences indicating that the DAA exhibited the advantages in the accurate prosthesis placement and less damage of surrounding hip musculature. However, a higher rate in dislocation, periprosthetic fracture, prosthesis loosening and nerve injury in the DAA group should be paid more attention, due to the limited exposure and a longer learning curve, compared to the LA.

Increasing but levelling out risk of revision due to infection after total hip arthroplasty: a study on 108,854 primary THAs in the Norwegian Arthroplasty Register from 2005 to 2019

Background and purpose - Focus on prevention, surveillance, and treatment of infection after total hip arthroplasty (THA) in the last decade has resulted in new knowledge and guidelines. Previous publications have suggested an increased incidence of surgical revisions due to infection after THA. We assessed whether there have been changes in the risk of revision due to deep infection after primary THAs reported to the Norwegian Arthroplasty Register (NAR) over the period 2005-2019.Patients and methods - Primary THAs reported to the NAR from January 1, 2005 to December 31, 2019 were included. Adjusted Cox regression analyses with the first revision due to deep infection after primary THA were performed. We investigated changes in the risk of revision as a function of time of primary THA. Time was stratified into 5-year periods. We studied the whole population of THAs, and the subgroups: all-cemented, all-uncemented, reverse hybrid (cemented cup), and hybrid THAs (cemented stem). In addition, we investigated factors that were associated with the risk of revision, and changes in the time span from primary THA to revision.Results - Of the 108,854 primary THAs that met the inclusion criteria, 1,365 (1.3%) were revised due to deep infection. The risk of revision due to infection, at any time after primary surgery, increased through the period studied. Compared with THAs implanted in 2005-2009, the relative risk of revision due to infection was 1.4 (95% CI 1.2-1.7) for 2010-2014, and 1.6 (1.1-1.9) for 2015-2019. We found an increased risk for all types of implant fixation. Compared to 2005-2009, for all THAs, the risk of revision due to infection 0-30 days postoperatively was 2.2 (1.8-2.8) for 2010-2014 and 2.3 (1.8-2.9) for 2015-2019, 31-90 days postoperatively 1.0 (0.7-1.6) for 2010-2014 and 1.6 (1.0-2.5) for 2015-2019, and finally 91 days-1 year postoperatively 1.1 (0.7-1.8) for 2010-2014 and 1.6 (1.0-2.6) for 2015-2019. From 1 to 5 years postoperatively, the risk of revision due to infection was similar to 2005-2009 for both the subsequent time periodsInterpretation - The risk of revision due to deep infection after THA increased throughout the period 2005-2019, but appears to have levelled out after 2010. The increase was mainly due to an increased risk of early revisions, and may partly have been caused by a change of practice rather than a change in the incidence of infection.

Comparison of direct anterior approach and posterior approach total hip arthroplasty: More than 5-year follow-up

Purpose

In this study we compare the surgical outcome of DAA and PA more than 5-year follow-up evaluation.

Materials and methods

This is a retrospective cohort single-surgeon study of consecutive primary THAs using the DAA or PA.

Results

There was no significant difference in HHS and JHEQ score. Posterior dislocation occurred in 4 cases in PA group (9.5%, p = 0.038) while there was no dislocation in DAA group.

Conclusion

Both DAA and PA yield good results at the final follow-up in terms of function, quality of life, and survivorship. However dislocation was significantly higher in PA group.

Cemented Femoral Fixation Using a Direct Anterior Approach: Background, Indications, and Surgical Technique

The use of the direct anterior approach (DAA) in total hip arthroplasty has increased dramatically over the past decade. Potential benefits of the DAA include earlier functional recovery and lower risk of periprosthetic dislocation, but issues with periprosthetic fracture and femoral loosening have been reported, particularly in elderly patients. Cemented femoral fixation may offer a means to decrease early femoral failure in elderly patients undergoing the DAA. Here, we will present a step-by-step technique for cementing the femoral implant through the DAA.

Preoperative Risk Prediction Models for Short-Term Revision and Death After Total Hip Arthroplasty: Data from the Finnish Arthroplasty Register

Because of the increasing number of total hip arthroplasties (THAs), even a small proportion of complications after the operation can lead to substantial individual difficulties and health-care costs. The aim of this study was to develop simple-to-use risk prediction models to assess the risk of the most common reasons for implant failure to facilitate clinical decision-making and to ensure long-term survival of primary THAs.

Direct anterior approach versus posterolateral approach in total hip arthroplasty: a meta-analysis of results on early post-operative period

Background

This study was performed to compare the advantage and disadvantage of posterolateral approach (PLA) and direct anterior approach (DAA) in total hip arthroplasty (THA).

Methods

Relevant trials were identified via a search of the Cochrane Central Register of Controlled Trials and PubMed from inception to 1 June 2019. A meta-analysis was performed to compare postoperative perioperative and radiographic outcomes between DAA and PLA in THA with respect to the hospital stay, blood loss, incision length, operative time, complications, and femoral and cup component position. The Harris Hip Score (HHS) was also assessed before and after 6 months postoperatively.

Results

Nine eligible studies involving 22698 adult patients (DAA group, n = 2947; PLA group, n = 19751) were identified for analysis. Compared with the PLA group, the DAA group had shorter hospital stay and achieved better HHS within 6 months after operation (P < 0.05), but the HHS was no significant differences between the two groups over 6 months (P > 0.05). The DAA group had significantly longer operative time, more blood loss, and complications than the PLA group (P < 0.05). In addition, the femoral component positioned in neutral and cup component inclination angle was comparable between both groups (P > 0.05); however, cup component anteversion angle was significantly larger in the PLA group (P < 0.05).

Conclusion

Patients in the DAA group had higher HHS within 6 months and shorter hospital stay. The DAA could offer rapid early functional recovery after THA compared with the PLA. However, the DAA group often required longer operative time and had more blood loss. Furthermore, there was a higher early complication rate. Therefore, we believe that the direct anterior approach was a more difficult technique. The surgeon should be a well-trained joint surgeon with extensive prior hip replacement experience before performing THA through a DAA, and DAA was not suitable for beginners performing THA. In addition, we did not observe the difference with regard to the femoral component position and cup component inclination angle except for the smaller cup component anteversion angle in DAA group.

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.

Comparison Between the Direct Anterior and Posterior Approaches for Total Hip Arthroplasty Performed for Femoral Neck Fracture

OBJECTIVES

To compare 90-day and 1-year outcomes, including mortality, of femoral neck fracture patients undergoing total hip arthroplasty (THA) by direct anterior approach (DAA) versus posterior approach (PA).

DESIGN

Retrospective cohort.

SETTING

Level I Trauma Center.

PATIENTS

One hundred forty-three consecutive intracapsular femoral neck fractures treated with THA from 2010 to 2018. The minimum follow-up was 12 months, and the average follow-up was 14.6 months (12-72 months).

MAIN OUTCOME MEASURES

Postoperative outcomes, including discharge ambulation, dislocation, periprosthetic joint infection, revision THA, and mortality at 90 days and 1 year after THA.

RESULTS

Of the 143 THA included, 44 (30.7%) were performed by DAA while 99 (69.3%) were performed by PA. In-hospital outcomes were similar between the cohorts. Compared with DAA patients, PA patients were more likely to ambulate without assistance preinjury (88.9% vs. 72.7%, P = 0.025) and be nonambulatory at the time of discharge (27.3% vs. 11.4%, P = 0.049). There were no significant differences in 90-day and 1-year postoperative outcomes between the DAA and PA groups, including dislocation, periprosthetic joint infection, periprosthetic fracture, mechanical complications, and revision surgery. Although there was no difference in mortality rate at 90 days, at 1-year follow-up the mortality rate was lower in the DAA group (0% vs. 11.1%, P = 0.018).

CONCLUSIONS

Performing THA by DAA provides similar benefits in regards to medical and surgical outcomes compared with the PA for displaced femoral neck fracture. However, the DAA may lead to decreased 1-year mortality rates, possibly, because of improved early ambulation capacity that is an important predictor of long-term mortality.

LEVEL OF EVIDENCE

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

Axial pelvic tilt in direct anterior Total hip Arthroplasty using a traction table

BACKGROUND

Direct anterior approach total hip arthroplasty may be undertaken on a traction table, but the effects that patient positioning can have on axial pelvic tilt (aPT) are unknown. The aim of this study was to assess the degree of error from patient positioning on the traction table during anterior minimally-invasive surgery (AMIS) THA.

METHODS

Patients were included who underwent direct anterior THA via the AMIS technique at a single institution between 11/2018 and 03/2019. Axial pelvic tilt was measured (a) in the supine position on the operating table, and (b) after positioning on the traction table, by the same consultant surgeon in all cases.

RESULTS

In the above-mentioned study period, 50 patients (F: 32; M: 18) with an average age of 60.6 ± 13.6 (range: 26.5 to 88.3) years, and an average BMI of 27.2 ± 5.0 (range: 17.9 to 41.5) kg/m² met the inclusion criteria. When measured in supine position, the average aPT was - 0.2 ± 1.7 (range: - 5.6 to 3.8) degrees. After positioning on the traction table, the average aPT was - 3.5 ± 2.1 (- 8.5 to 1.6) degrees (p < 0.001). In patients with an aPT of more than 5 degrees, the caput-collum-diaphyseal (CCD) angle was significantly lower (125 ± 11° vs. 134 ± 8°, p = 0.007).

CONCLUSION

This study raises awareness for the potential risk of aPT during positioning of the patient on the traction table, commonly used during direct anterior THA via the AMIS technique.

Early Rate of Revision of Total Hip Arthroplasty Related to Surgical Approach: An Analysis of 122,345 Primary Total Hip Arthroplasties

BACKGROUND

A number of surgical approaches are available for total hip arthroplasty (THA), but there are limited large-volume, multi-surgeon data comparing the rates of early revisions following these approaches. The aim of this study was to compare the rate of revision of primary conventional THA related to surgical approach.

METHODS

Data from the Australian Orthopaedic Association National Joint Replacement Registry were analyzed for all patients who had undergone a primary THA for osteoarthritis from January 2015 to December 2018. The primary outcome measure was the cumulative percent revision (CPR) for all causes. Secondary outcome measures were major revision (a revision procedure requiring change of the acetabular and/or femoral component) and revision for specific diagnoses: fracture, component loosening, infection, and dislocation. Age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) score, femoral head size, and femoral fixation were assessed as potential confounders.

RESULTS

There was a total of 122,345 primary conventional THAs for which the surgical approach was recorded in the registry; 65,791 were posterior, 24,468 were lateral, and 32,086 were anterior. There was no difference in the overall CPR among approaches, but the anterior approach was associated with a higher rate of major revisions. There were differences among the approaches with regard to the types of revision. When adjusted for age, sex, ASA score, BMI, femoral head size, and femoral fixation, the anterior approach was associated with a higher rate of femoral complications-i.e., revision for periprosthetic fracture and femoral loosening. There was a lower rate of revision for infection after the anterior approach compared with the posterior approach in the entire period, and compared with the lateral approach in the first 3 months. The posterior approach was associated with a higher rate of revision for dislocation compared with both the anterior and the lateral approach in all time periods. The anterior approach was associated with a lower rate of revision compared with the lateral approach in the first 6 months only.

CONCLUSIONS

There was no difference in the overall early CPR among the surgical approaches, but the anterior approach was associated with a higher rate of early major revisions and femoral complications (revisions for periprosthetic fracture and femoral loosening) compared with the posterior and lateral approaches and with a lower rate of dislocation and infection.

LEVEL OF EVIDENCE

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

Direct anterior approach or posterior approach in total hip arthroplasty: A direct comparative study protocol

BACKGROUND

Two familiar surgical methods, posterior approach (PA) and direct anterior approach (DAA), have been extensively utilized in the treatment of total hip arthroplasty (THA) with similar long-term rates of success. The sufficient sample size and a good clinical trial are urgently needed. Considering the above factors, we implemented a retrospective research to compare the prognosis of patients with primary THA receiving the techniques of PA or DAA.

METHODS

This is an observational retrospective research that prospectively collected information via several surgeons at a center utilizing the 2 above treatment methods for unilateral primary total hip arthroplasty. A review of primary THA performed with DAA or PA between February 2017 and February 2019 was conducted in our hospital. The inclusion criteria contained the degenerative changes in end-stage of hip owing to the rheumatoid arthritis, inflammatory arthritis, and osteoarthritis, as well as the Crowe I and II dysplasia that did not require the enhancement. The primary endpoint was the Harris hip score. The measures of secondary outcome contained the operation time, length of incision, hospital stay, the complications after operation, as well as patient satisfaction. The Statistical Package for Social Sciences version 20.0 was utilizing for the statistical analysis (IBM Corporation, Armonk, NY).

RESULTS

We assumed that the 2 treatment methods possess similar results.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry6008).

Is there a reduction in risk of revision when 36-mm heads instead of 32 mm are used in total hip arthroplasty for patients with proximal femur fractures?

Background and purpose - 32-mm heads are widely used in total hip arthroplasty (THA) in Scandinavia, while the proportion of 36-mm heads is increasing as they are expected to increase THA stability. We investigated whether the use of 36-mm heads in THA after proximal femur fracture (PFF) is associated with a lower risk of revision compared with 32-mm heads.Patients and methods - We included 5,030 patients operated with THA due to PFF with 32- or 36-mm heads from the Nordic Arthroplasty Register Association database. Each patient with a 36-mm head was matched with a patient with a 32-mm head, using propensity score. The patients were operated between 2006 and 2016, with a metal or ceramic head on a polyethylene bearing. Cox proportional hazards models were fitted to estimate the unadjusted and adjusted hazard ratio (HR) with 95% confidence intervals (CI) for revision for any reason and revision due to dislocation for 36-mm heads compared with 32-mm heads.Results - 36-mm heads had an HR of 0.9 (CI 0.7-1.2) for revision for any reason and 0.8 (CI 0.5-1.3) for revision due to dislocation compared with 32-mm heads at a median follow-up of 2.5 years (interquartile range 1-4.4).Interpretation - We were not able to demonstrate any clinically relevant reduction of the risk of THA revision for any reason or due to dislocation when 36-mm heads were used versus 32-mm. Residual confounding due to lack of data on patient comorbidities and body mass index could bias our results.

Posterior approach, fracture diagnosis, and American Society of Anesthesiology class III-IV are associated with increased risk of revision for dislocation after total hip arthroplasty: An analysis of 33,337 operations from the Finnish Arthroplasty Register

Background and objective:

Dislocation is one of the most common reasons for revision surgery after primary total hip arthroplasty. Both patient related and surgical factors may influence the risk of dislocation. In this study, we evaluated risk factors for dislocation revision after total hip arthroplasty based on revised data contents of the Finnish Arthroplasty Register.

Methods:

We analyzed 33,337 primary total hip arthroplasties performed between May 2014 and January 2018 in Finland. Cox proportional hazards regression was used to estimate hazard ratios with 95% confidence intervals for first dislocation revision using 18 potential risk factors as covariates, such as age, sex, diagnosis, hospital volume, surgical approach, head size, body mass index, American Society of Anesthesiology class, and fixation method.

Results:

During the study period, there were 264 first-time revisions for dislocation after primary total hip arthroplasty. The hazard ratio for dislocation revision was 3.1 (confidence interval 1.7–5.5) for posterior compared to anterolateral approach, 3.0 (confidence interval 1.9–4.7) for total hip arthroplasties performed for femoral neck fracture compared to total hip arthroplasties performed for osteoarthritis, 2.0 (confidence interval 1.0–3.9) for American Society of Anesthesiology class III–IV compared to American Society of Anesthesiology class I, and 0.5 (0.4–0.7) for 36-mm femoral head size compared to 32-mm head size.

Conclusions:

Special attention should be paid to patients with fracture diagnoses and American Society of Anesthesiology class III–IV. Anterolateral approach and 36-mm femoral heads decrease dislocation revision risk and should be considered for high-risk patients.

A Comparison of Risk of Dislocation and Cause-Specific Revision Between Direct Anterior and Posterior Approach Following Elective Cementless Total Hip Arthroplasty

BACKGROUND

Use of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased over the last decade. We sought to investigate whether (1) a difference exists in dislocation risk for DAA compared with posterior THA, (2) a difference exists in risk for specific revision reasons, and (3) the likelihood of adverse 90-day postoperative events differs.

METHODS

We conducted a cohort study using data from Kaiser Permanente's Total Joint Replacement Registry. Patients aged ≥18 years who underwent primary cementless THA for osteoarthritis with a highly cross-linked polyethylene liner were included (2009-2017). Multivariable Cox proportional hazards regression was used to evaluate dislocation and cause-specific revision risks, and multivariable logistic regression was used to evaluate 90-day emergency department visits, 90-day unplanned readmissions, and 90-day complications (including deep infection, deep vein thrombosis, and pulmonary embolism).

RESULTS

Of 38,399 primary THA, 6428 (16.7%) were DAA. All-cause revision at 2-years follow-up was 1.78% (95% confidence interval [CI] = 1.46-2.17) for DAA and 2.28% (95% CI = 2.11-2.45) for posterior. After adjusting for covariates, DAA had a lower risk of dislocation (hazard ratio [HR] = 0.39, 95% CI = 0.29-0.53), revision for instability (HR = 0.33, 95% CI = 0.18-0.58), revision for periprosthetic fracture (HR = 0.57, 95% CI = 0.34-0.96), and readmission (odds ratio = 0.82, 95% CI = 0.67-0.99) compared with posterior approach but a higher risk of revision for aseptic loosening (HR = 2.26, 95% CI = 1.35-3.79).

CONCLUSION

While the DAA associated with lower risks of dislocation and revision for instability and periprosthetic fracture, it is associated with a higher revision risk for aseptic loosening. Surgeons should discuss these risks with their patients.

Proceeding from direct lateral to anterolateral approach in total hip arthroplasty: A closer look on radiological and clinical aspects

Introduction

Since less invasive approaches for total hip arthroplasty (THA) are promoted, our aim was to compare direct lateral (DLA) and anterolateral approach (ALA) under otherwise identical conditions.

Methods

Pre - and postoperative x-rays from 200 propensity matched patients (DLA vs. ALA) were evaluated for anatomical reconstruction.

Results

Overall, the cup position was within the safe zone in both group while the mean center of rotation (COR) was placed more medial and cranial in both groups compared to preoperative anatomy (p > 0.05). The mean leg elongation was comparable between both approaches (p > 0.05). Postoperatively the WOMAC improved about 90%.

Conclusion

This study confirmed that the ALA can be safely used for THA in minimal invasive setting.

Surgical approach does not affect deep infection rate after primary total hip arthroplasty

BACKGROUND

There is a concern for higher rates of wound complications and a potentially increased periprosthetic joint infection (PJI) risk after total hip arthroplasty (THA) with the direct anterior approach (DAA) compared to the posterolateral approach (PLA). Our purpose was to compare PJI risk after THA with the DAA or the PLA and to identify risk factors for PJI after primary THA.

METHODS

Clinical characteristics of patients treated in our institution with primary DAA or PLA THA between 1/2010 and 12/2015 were retrospectively reviewed. The respective deep PJI rates were calculated. A logistic regression model was constructed to determine a potential difference in the PJI risk between the 2 groups, and risk factors for hip PJI in all patients.

RESULTS

During the period studied, there were 1,182 DAA THAs and 18,853 PLA THAs. The PJI rate was 0.25% for the DAA group and 0.31% for the PLA group (p = 1.0). The DAA was not associated with a significantly increased risk for PJI compared to the PLA. Compared to younger patients, older patients had lower PJI risk; patient discharge to home was also associated with lower PJI risk compared to other discharge disposition; longer length of stay was associated with higher PJI risk compared to shorter length of stay.

CONCLUSION

The DAA is equally safe compared the PLA with respect to PJI risk. Younger age, discharge to facilities other than home and increased length of stay increase the risk for deep PJI after primary THA.

Thirty-Day Major and Minor Complications Following Total Hip Arthroplasty-A Comparison of the Direct Anterior, Lateral, and Posterior Approaches

BACKGROUND

The choice of surgical approach during total hip arthroplasty (THA) remains highly controversial. The aim of the present study was to compare 30-day major and minor complications, following primary THA between the direct anterior, lateral, and posterior approaches.

METHODS

Our hospital performs primary THAs using all 3 aforementioned approaches based on surgeon preference. Patients who underwent primary THA from August 2010 to August 2017 were identified using our institution's total joint registry, and their data were combined with prospectively collected data from the National Surgical Quality Improvement Program database (which evaluates a random sample of approximately 20% of all surgical patients in our hospital). Baseline characteristics, operative variables, and postoperative complications were then compared between the three groups.

RESULTS

The analysis comprised 1967 primary THAs (1913 patients), whereby 56%, 29%, and 15% were performed through a posterior, lateral, and direct anterior approach, respectively. Thirty-day major and minor complications occurred in 3.9% and 9.4% of surgeries, respectively. After adjusting for baseline patient characteristics, there was no significant difference in major or minor perioperative complications between the 3 approaches.

CONCLUSIONS

This study compared perioperative complications between the 3 most commonly used approaches for THA utilizing a synthesis of our institutional total joint registry and high-quality National Surgical Quality Improvement Program data. Thirty-day major and minor complications were similar regardless of the surgical approach employed, which may help surgeons and patients simplify the multiple considerations taken into account when deciding on surgical approach for primary THA.

LEVEL OF EVIDENCE

Therapeutic, Level III.

Incidence of Heterotopic Ossification in Anterior Based Muscle Sparing Total Hip Arthroplasty: A Retrospective Radiographic Review

Heterotopic ossification (HO) is a known complication following total hip arthroplasty (THA). The anterior based muscle sparing (ABMS) approach is a variation of a direct anterior approach through the Watson–Jones interval. To date, few studies have evaluated HO formation following this surgery. We examine the incidence of HO in a consecutive series of THAs using this approach by three different surgeons at a single center. Standard preoperative radiographs were examined to determine the type of degenerative arthritis, and follow-up radiographs a minimum of 9 months after surgery were evaluated for the presence and classification of HO. The overall incidence of HO after ABMS THA in this study was 86/233, or 36.9%, which is comparable to recent studies of direct anterior and traditional approaches. Class III and IV HO is uncommon in ABMS surgery (3.9% and 1.3%, respectively) and appears to decrease with increased surgical experience with this technique.

Short-term outcomes of the supine muscle-sparing anterolateral versus direct lateral approach to primary total hip arthroplasty

BACKGROUND

Although total hip arthroplasty (THA) is among the most successful orthopaedic procedures, it is not without complications. As such, finding the optimal surgical approach has become an area of particular interest. In this study, we compare: (1) pain intensity; (2) opioid consumption; (3) lengths of stay (LOS); (4) complication rates; (5) discharge destination; and (6) ambulatory function between patients who underwent THA via the supine muscle-sparing anterolateral (MS-ALA) and conventional direct lateral (DLA) approaches.

METHODS

A retrospective analysis was conducted on 220 consecutive patients who received primary THA using the supine MS-ALA (n = 101) or DLA (n = 119) between 1 January 2014 and 31 December 2016. Outcomes included postoperative pain intensity, opioid consumption, LOS, discharge destination, complications, additional procedures, and time to independent ambulation.

RESULTS

We demonstrated significantly lower opioid consumption on postoperative days (POD) 1 and 2 (mean differences, -32.0 and -28.4 mg, respectively; p ⩽ 0.001) and decreased pain intensity during the second 24 hours of the hospital stay (mean difference, -22.0; p < 0.001) in patients receiving the MS-ALA. Relative to the DLA cohort, patients in the MS-ALA cohort were 2.04 times more likely to be discharged to home (p = 0.028) and 1.91 times less likely to experience postoperative abductor insufficiency (p = 0.039).

CONCLUSION

The present study is the 1st to compare postoperative outcomes, particularly pain intensity and opioid consumption, between the supine muscle-sparing anterolateral and direct lateral THA approaches. Further research should investigate the effect of surgical approach on quality and cost of care, include larger sample sizes, and involve longer-term follow-up.

Prospective, Randomized Study of Direct Anterior Approach vs Posterolateral Approach Total Hip Arthroplasty: A Concise 5-Year Follow-Up Evaluation

BACKGROUND

Interest in direct anterior approach (DAA) has increased over the last decade. In our previously published study comparing DAA to posterolateral approach (PA), early 3-month benefits were noted in terms of pain and function. There was no difference noted at 6 or 12 months. This study reports average 5-year follow-up of our original study.

METHODS

Originally there were 43 DAA patients and 44 PA patients. At an average 5-year follow-up, patients were evaluated clinically with a University of California at Los Angeles activity score, Harris hip score, and Hip Disability and Osteoarthritis Outcome Score Jr Survivorship analysis was calculated. Radiographs were evaluated for loosening and evidence of radiolucent lines.

RESULTS

There were 2 deaths 1 in each group, neither was related to the implant or procedure. Four patients were lost to follow-up: 2 in the DAA group and 2 in the PA group. There was no statistical difference between surgical approaches in terms of Harris hip score, University of California at Los Angeles activity score, and Hip Disability and Osteoarthritis Outcome Score Jr. The 7-year survivorship was not significantly different. There were no loose implants at average 5-year follow-up.

CONCLUSION

Both DAA and PA yield good results at an average 5-year follow-up in terms of survivorship, function, rate of complications, and radiographic analysis.

Mechanical Complications Following Total Hip Arthroplasty Based on Surgical Approach: A Large, Single-Institution Cohort Study

BACKGROUND

The influence of surgical approach on risk of early postoperative mechanical complications after total hip arthroplasty (THA) continues to be a focus of debate. We performed the first single-institution study on risk of early operative and nonoperative mechanical complications after THA based on approach, with the hypothesis that there would be no clinically significant difference with modern surgical methods.

METHODS

A retrospective study was conducted on 16,186 consecutive THA performed from 2010 to 2016. Revision or conversion THA and cases performed for hip fracture, with recalled prostheses, or during a surgeon's learning period were excluded. THAs were performed using direct anterior (DA; n = 5465), direct lateral (DL; n = 8561), or posterolateral approach with soft tissue repair (PL; n = 2160). All mechanical complications within the first 2 years were identified. The primary analysis was a time to event Cox regression, accounting for both patient and surgeon characteristics.

RESULTS

Compared with the DL approach, risk of mechanical complications was higher for both DA and PL. Adjusted risk of instability within 2 years was 0.17%, 0.74%, and 1.74% for DL, DA, and PL, respectively. While occurring at similar rates with the PL and DL approaches, the risk of periprosthetic fracture and loosening increased with DA. Consequently, femoral failure, including fracture or loosening, occurred more frequently for DA, with an adjusted incidence of 1.20% vs 0.58% and 0.47%, with DL and PL.

CONCLUSION

Even with soft tissue repair, instability continues to occur with increased frequency with the PL approach. While reducing dislocation, a higher risk of femoral failure with DA must also be considered. Nevertheless, the DL approach appears to confer the lowest overall risk of mechanical complications.