The incidence of hip dislocation and suture failure according to two different types of posterior soft tissue repair techniques in total hip arthroplasty: a prospective randomized controlled trial

The "true" 1-year incidence of dislocation after primary total hip arthroplasty: validation of an algorithm identifying dislocations in the Danish National Patient Register based on 5,415 patients from the Danish Hip Arthroplasty Register

BACKGROUND AND PURPOSE

Dislocations continue to be a serious complication after primary total hip arthroplasty (THA). Our primary aim was to report the "true" incidence of dislocations in Denmark and secondarily to validate a previously developed algorithm designed to identify THA dislocations in the updated version of the Danish National Patient Register (DNPR), based on data from the Danish Hip Arthroplasty Register (DHR).

METHODS

We included 5,415 primary THAs from the DHR performed from July 1 to December 31, 2019. Version 3 of the DNPR was launched in February 2019, and a combination of data from the DNPR and a comprehensive national review of 1,762 hospital contacts enabled us to identify every dislocation occurring during the 1st year after THA to determine the "true" 1-year incidence of dislocation. The results were presented as proportions with 95% confidence intervals (CI), and validation was performed by calculating sensitivity and predictive values.

RESULTS

The "true" 1-year incidence of dislocation was 2.8% (CI 2.4-3.3). Of these, 37% suffered recurrent dislocations during the follow-up period. Between-hospital variation ranged from 0.0% to 9.6%. The algorithm demonstrated a sensitivity close to 95%, while maintaining a positive predictive value of above 94%.

CONCLUSION

 The "true" 1-year incidence of dislocation of 2.8% is comparable to earlier findings, and large variation among hospitals continues to be evident. We have proven the algorithm to be valid in the latest DNPR (version 3), enabling it to be employed as a new quality indicator in future annual DHR reports.

Posterior Approach and Inferior Capsulotomy in Bipolar Hemiarthroplasty for Femoral Neck Fractures: Comparison with Superior Capsulotomy

Background

Hemiarthroplasty is frequently used to treat displaced femoral neck fractures in elderly patients, but it has a higher risk of postoperative dislocation. We introduced the posterior approach and inferior capsulotomy (PAICO) to enhance joint stability after bipolar hemiarthroplasty for femoral neck fracture. We evaluated whether the PAICO would have a lower dislocation rate than the conventional posterior approach with superior capsulotomy.

Methods

From January 2021 to December 2021, we prospectively recruited 25 patients (25 hips) aged 50 years or older who underwent bipolar hemiarthroplasty for femoral neck fractures due to low-energy trauma as the PAICO group. We compared the PAICO group with a historical control group who had undergone hemiarthroplasty in 7 institutes between 2010 and 2020. The primary endpoint was dislocation within 1 year after the surgery. We compared data from the PAICO group with the data from the historical control group from the Korean Hip Fracture Registry which was carried out in South Korea.

Results

A total of 25 patients (25 hips) were enrolled in the present study; 3,477 patients (3,571 hips) who underwent bipolar hemiarthroplasty were reviewed as the historical control group. In the PAICO group, we observed no dislocation, whereas the dislocation rate in the control group was 1.3%.

Conclusions

In patients with displaced femoral neck fractures, the PAICO approach demonstrated comparable results in operation time and complication rates when compared to bipolar hemiarthroplasty using superior capsulotomy. Notably, there were no observed cases of dislocation among patients who underwent the PAICO approach. We recommend this PAICO approach to surgeons using the posterior approach, hoping to prevent dislocation in bipolar hemiarthroplasty.

The Use of Barbed Sutures in Total Hip Arthroplasty: A Systematic Review on Clinical-Surgical Outcomes, Costs, and Complications

PURPOSE

Total hip arthroplasty is among the most successful procedures in orthopaedic surgery. As the total number of total hip arthroplasties is constantly rising and it is expected to further increase, efforts oriented to optimise surgical pathways are investigated, aiming to reduce complications and diminish costs. The wound suturing phase is one of the steps that may be addressed. Barbed sutures have proved to reduce surgical times and enhance suture stability, then reducing wound-related complications in many surgical fields. The evidence on the use of this technology in total hip arthroplasty is still sparse, and its effect on patient outcomes and costs must still be clarified.

METHODS

A systematic search of studies published from 1 January 2000 to 1 March 2023 was performed. Two authors independently reviewed the literature available in eight electronic databases to identify papers eligible for inclusion.

RESULTS

A total of nine studies investigating 6959 procedures on 6959 patients were included in the final analysis. Five studies were randomised controlled trials, and the overall quality of studies ranged from moderate to high. The mean age of patients ranged from 43.8 to 70 years. BMI ranged from 25 to 31.9 kg/m2. The mean follow-up of studies ranged from 3 to 6 months.

CONCLUSIONS

Evidence included in the systematic review suggested that the use of barbed sutures is associated with lower suturing times, complication rates, and overall costs when compared to the use of traditional suturing techniques.

LEVEL OF EVIDENCE

II, systematic review of level I and II studies.

Using mesh in capsule anatomical reconstruction to enhance the stability of high-dislocation-risk hip arthroplasty: a randomized controlled trial

BACKGROUND

Dislocation is a common complication after total hip arthroplasty (THA). This study aimed to compare the outcomes of mesh reconstruction versus conventional capsular repair in maintaining capsular integrity and preventing dislocation after THA.

METHODS

This was a prospective, randomized controlled study of consecutive patients. A total of 124 high-dislocation-risk THAs were identified and randomized into two groups, one using mesh reconstruction and the other using the conventional capsular repair method. Perioperative data and radiological data were collected. Patients were followed up regularly. The main indices were the capsular integrity assessed by magnetic resonance imaging (MRI) and hip dislocation rate. The secondary indices included the Harris hip score (HHS), complications, and satisfaction.

RESULTS

A total of 106 patients completed the follow-up and the average follow-up times were 19 ± 3.1 and 18 ± 3.3 months. The operation time of the mesh group was longer than that of the conventional group (P < 0.001). There were minor differences in acetabular anteversion and abduction angle, and the other data showed no differences. MRI results indicated that the success rate of capsular repair was higher in the mesh group (50 hips, 98%) than in the conventional group (37 hips, 67%) (P < 0.001), and the others failed the repair. Three dislocations occurred in the conventional group, while none occurred in the mesh group. The preoperative HHS (30 points) and postoperative HHS (82 points) of the mesh group were similar to those (35 points, 83 points) of the conventional group (P = 0.164, P = 0.328). Satisfaction had no difference (P = 0.532).

CONCLUSIONS

Compared to conventional repair, mesh reconstruction can effectively maintain capsular integrity and decrease dislocation risk after THA without increasing complications.

LEVEL OF EVIDENCE

Therapeutic study, Level IA.

How do dislocation rates differ between different approaches to total hip arthroplasty? A systematic review and meta-analysis

Background: Different surgical approaches for total hip arthroplasty (THA) exist, without predisposition when it comes to dislocation risk. The direct anterior approach (DAA) is thought to have reduced risk since soft tissue trauma is minimalized. Therefore, we assessed the dislocation risk for different surgical approaches, and the relative dislocation risk of DAA compared to other approaches. Methods: Six electronic databases were systematically searched for prospective studies reporting dislocation following THA. Proportion meta-analyses were performed to assess the dislocation rate for subgroups of the surgical approach. Meta-analysis for binary outcomes was performed to determine the relative risk of dislocation for the DAA compared to other approaches. Results: Eleven studies with 2025 patients were included (mean age 64.6 years, 44% male, mean follow-up 10.5 months), of which four studies were also used in the risk ratio meta-analysis. Overall dislocation rate was 0.79% (95% CI 0.37–1.69). Subgroup analyses showed that most dislocations occurred in the posterior approaches group (1.38%), however non-significant. Furthermore, the DAA emerged with a non-significant lower risk of dislocation (RR 0.37, 95% CI 0.05–2.46) compared to other surgical approaches. Conclusion: Current literature shows non-significant predisposition for a surgical approach to THA regarding dislocation risk. To what extent patient characteristics influence the risk of dislocation could not be determined. Future research should focus on this, as well as on the influence of a surgeon's experience with a specific approach.

Do Different Approaches Make a Difference in Isokinetic Performance in Elderly Patients With Femoral Neck Fracture Who Underwent Bipolar Endoprosthesis?

Background There are ongoing doubts about the effects of the commonly used anterolateral approach (ALA) and posterolateral approach (PLA) for bipolar hemiarthroplasty (BHA) on hip muscle strength after surgery. In this study, it was aimed to evaluate the isokinetic performance of the operated and non-operated hips in patients with femoral neck fractures who underwent BHA with PLA or ALA and to compare the isokinetic performance of the hips and functional results between the two approaches. Materials and methods Forty-one patients who underwent unilateral BHA with PLA or ALA for femoral neck fracture between February 2019 and December 2020 were enrolled. The isokinetic performance of the flexor, extensor, and abductor muscles of the operated and non-operated hips were evaluated by measuring peak torque, total work, and average power. Functional status was assessed using Harris Hip Score and Short Form 36. Results The patients were divided into two groups; those operated with PLA (n=22) and with ALA (n=19). The groups had similar demographic and clinical characteristics. All isokinetic parameters of the operated hips did not differ between the groups (all p>0.05). In both groups, all isokinetic parameters were significantly lower in the operated hips than in the non-operated hips. Conclusion Although there are debates about potential extensor muscle injury with PLA and potential abductor muscle injury with ALA, this study showed that functional results and the isokinetic performance of both approaches were not different.

The incidence of hip dislocation after posterior approach primary total hip arthroplasty: comparison of two different posterior repair techniques

INTRODUCTION

Total hip arthroplasty (THA) remains one of the most successful orthopedic surgical procedures. The posterior approach is associated with a higher incidence of post-operative dislocations than others. Adequate posterior soft tissue repair techniques, including capsulorrhaphy and transosseous bone sutures in the greater trochanter effectively reduce the dislocation rate. Post-operative "posterior hip precautions" were historically believed to reduce dislocation risks, although not clearly proven. The first protocol consists of capsulorrhaphy with the prescription of post-operative posterior hip precautions (TT) and the second, transosseous bone sutures without precautions (TB). This study aims to determine the optimal protocol to decrease the dislocation rate following posterior approach primary THA.

MATERIALS AND METHODS

A 10-year retrospective case-control chart review analyzed demographic, pre-, intra-, and post-surgical parameters. Primary outcomes were the difference in dislocation and revision surgery rates between protocols. Secondary outcomes included the incidence of recurrent dislocations and the identification of predictors of dislocation.

RESULTS

2,242 THAs were reviewed and 26 (1.2%) resulted in dislocation. Increased age (p = 0.04) ASA score (p = 0.03) and larger acetabular cup size (p < 0.001) were associated with heightened risk. Tendon to tendon (TT) repair saw a 1.62% dislocation rate versus 0.98% for tendon-to-bone (TB) repair, although statistically insignificant (p = 0.2). Transosseous repair resulted in recurrent dislocations for 8/16 (50%) patients compared to 6/10 (60%) in the suture group (p ≤ 0.001). No significance was found for prescription of posterior hip precautions.

CONCLUSIONS

To our knowledge, this is the first study to perform a direct comparison of TT repair with posterior precautions to TB repair without posterior precautions. Similarity in dislocation rate, decreased recurrent events and the alleviated patient burden from precautions leads the authors to recommend the TB repair without precautions for a successful THA.

The Fragility Index of Total Hip Arthroplasty Randomized Control Trials: A Systematic Review

INTRODUCTION

Although randomized controlled trials (RCTs) are considered the benchmark study design, a change of outcomes for a few patients can lead to a reversal of study conclusions. As such, examination of the fragility index (FI) of RCTs has become an increasingly popular method to provide further information regarding the relative robustness of RCT results. The purpose of this study was to systematically characterize and assess the predictors of the FI RCTs in total hip arthroplasty literature.

METHODS

PubMed/MEDLINE, Embase, and Cochrane were systematically searched for all total hip arthroplasty RCTs published between January 2015 and December 2020, which had an equal assignment of participants to a two parallel-arm study design, examined a surgical intervention, and reported on at least one statistically significant dichotomous outcome in the abstract. Potential factors associated with the FI were examined using the Spearman correlation and Mann-Whitney U test.

RESULTS

Thirty-four RCTs were selected, with a median number of study participants of 111 (interquartile range [IQR] 72-171] and a median total number of events of 15 (IQR 9.5 to 29). The median FI was 2 (IQR 1 to 6), while six studies had a FI of 0. In 18 cases (52.9%), the number of patients needed to change from no event to event was less than that loss to follow-up. Larger sample size was found to predictive of a higher FI (rs = 0.367, P = 0.033), but the year of publication, journal impact factor, the calculated power analysis size, and loss to follow-up were not associated with FI.

CONCLUSION

The FI serves as a useful addition to other more commonly used approaches of quantitative analyses, such as P values, effect sizes, and confidence intervals, and widespread reporting the FI may provide clinicians with further information about RCT results.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

Clinical results of short external rotators preserving posterolateral approach for hemiarthroplasty after femoral neck fractures in elderly patients

INTRODUCTION

Even though the dislocation rate is lower in the hemiarthroplasty (HA) than total hip arthroplasty, it has still developed as one of serious complications in elderly patients. We have used short external rotators (SER) preserving posterolateral approach to reduce dislocation after hip arthroplasty, especially in elderly patients. The present study was conducted to introduce SER preserving posterolateral approach and report the dislocation rate after HA via this approach in elderly patients with femoral neck fractures.

METHODS

Between January 2015 and July 2019, 307 consecutive elderly patients aged over 70 years who underwent cementless bipolar HA for femoral neck fractures and were followed up for at least one year, were enrolled in this study. All surgeries were performed using the SER preserving posterolateral approach. The demographic and perioperative data were examined and the complications including dislocation were investigated.

RESULTS

Mean operation time was 54.3 min, and mean estimated blood loss was 252.4 cc. The mean follow-up time was 22.1 months, HHS was 67.5 points at the final examination Dislocation following HA developed in only one patient (0.3%) with dementia during hospital stay, which was reduced closely with no subsequent recurrence. Periprosthetic femoral fracture occurred in two patients, which was treated with internal fixation in one patient and with stem revision in the other patient. There was no surgical site infection or periprosthetic infection as complications.

CONCLUSION

The SER preserving technique in posterolateral approach effectively can be effective for reducing the dislocation after HA in elderly patients with femoral neck fracture. It can be encouraged in posterolateral approach for HA, especially in elderly patients under the risk of dislocation.

The role of the femoral component orientation on dislocations in THA: a systematic review

INTRODUCTION

Dislocation remains a major complication in total hip arthroplasty (THA), in which femoral component orientation is considered a key parameter. New imaging modalities and definitions on femoral component orientation have been introduced, describing orientation in different planes. This study aims to systematically review the relevance of the different orientation parameters on implant stability.

METHODS

A systematic review was performed according to the PRISMA guidelines to identify articles in the PubMed and EMBASE databases that study the relation between any femoral component orientation parameters and implant stability in primary THA.

RESULTS

After screening for inclusion and exclusion criteria and quality assessment, nine articles were included. Definitions to describe the femoral component orientation and methodologies to assess its relevance for implant stability differed greatly, with lack of consensus. Seven retrospective case-control studies reported on the relevance of the transversal plane orientation: Low femoral- or low combined femoral and acetabular anteversion was statistical significantly related with more posterior dislocations, and high femoral- or combined femoral and acetabular anteversion with anterior dislocations in two studies. There were insufficient data on sagittal and coronal component orientation in relation to implant stability.

CONCLUSION

Because of incomparable definitions, limited quality and heterogeneity in methodology of the included studies, there is only weak evidence that the degree of transverse component version is related with implant stability in primary THA. Recommendations about the optimal orientation of the femoral component in all three anatomical planes cannot be provided. Future studies should uniformly define the three-dimensional orientation of the femoral component and systematically describe implant stability.

Durability of transosseous repair of posterior soft tissues after primary total hip arthroplasty: a prospective randomized controlled trial

PURPOSE

Posterior soft tissue repair is one of the methods for preventing dislocation after total hip arthroplasty (THA). This study aimed to evaluate durability of two separate suture materials in THA patients who underwent posterior soft tissue repair.

METHODS

42 THA patients were included in the study. The patients were randomly divided into two groups, where braided nonabsorbable suture was used in group A (n = 22), while braided absorbable suture was used in group B (n = 20). While repairing the posterior soft tissues, the piriformis and triceps coxae tendons together with the capsule were reattached to the greater trochanter via pull out sutures. Two hemoclips were attached as distance markers to both pull out sutures on the medial and lateal sides of the greater trochanter. Anteroposterior radiographs were taken one day, 15 days, 3 months and 6 months after operation. Distances between the hemoclips medial and lateral to the greater trochanter were measured on the radiographs, and the closest distances were recorded. The repair was considered a failure if the difference of distances between the first and any of the follow-up measurements exceeded 15 mm.

RESULTS

No statistically significant difference was observed between the groups. In both groups, elongation magnitudes in all time intervals were statistically significant while the results obtained from measurements taken 15 days after operation were more significant (p < 0.01). No dislocations were observed.

CONCLUSION

We conclude that for transosseous posterior soft tissue repair in THA, both absorbable and nonabsorbable sutures are similarly durable and can be routinely performed.

A systematic review and meta-analysis of the hip capsule innervation and its clinical implications

Detailed understanding of the innervation of the hip capsule (HC) helps inform surgeons' and anaesthetists' clinical practice. Post-interventional pain following radiofrequency nerve ablation (RFA) and dislocation following total hip arthroplasty (THA) remain poorly understood, highlighting the need for more knowledge on the topic. This systematic review and meta-analysis focuses on gross anatomical studies investigating HC innervation. The main outcomes were defined as the prevalence, course, density and distribution of the nerves innervating the HC and changes according to demographic variables. HC innervation is highly variable; its primary nerve supply seems to be from the nerve to quadratus femoris and obturator nerve. Many articular branches originated from muscular branches of the lumbosacral plexus. It remains unclear whether demographic or anthropometric variables may help predict potential differences in HC innervation. Consequently, primary targets for RFA should be the anterior inferomedial aspect of the HC. For THA performed on non-risk patients, the posterior approach with capsular repair appears to be most appropriate with the lowest risk of articular nerve damage. Care should also be taken to avoid damaging vessels and muscles of the hip joint. Further investigation is required to form a coherent map of HC innervation, utilizing combined gross and histological investigation.

A Specific Capsular Repair Technique Lowered Early Dislocations in Primary Total Hip Arthroplasty Through a Posterior Approach

BACKGROUND

Dislocation is a challenging problem after total hip arthroplasty (THA). We sought to evaluate the incidence of early dislocation with 2 different posterior repair techniques after THA using a posterior approach.

METHODS

From September of 2008 to August of 2019, we evaluated 841 THAs performed by a single surgeon using a posterior approach. Before November of 2015, the capsule was repaired to the greater trochanter (group 1, 605 patients). Starting November 2015, the posterior capsule was repaired in a side-to-side fashion (direct soft-tissue repair) (group 2, 236 patients). There was a mean follow-up of 31.1 months (range, 2.5-122.5 months). A multivariable logistic regression model was constructed to assess the impact of baseline patient and operative factors on the dislocation rate.

RESULTS

There were 22 dislocations, all of which occurred in group 1. There were no dislocations in group 2. After adjusting for patient and operative factors, the direct soft-tissue repair had a large impact on the overall multivariable model as indicated by its effect likelihood ratio of 10.33 (P = .001); however, the odds ratio was not calculable for this factor, given that there were no dislocations in hips with direct soft-tissue repair. Increasing age was associated with an increased odds of dislocation (odds ratio, 1.04, P = .017), with an effect likelihood ratio of 6.25 (P = .012).

CONCLUSIONS

Switching from a capsular repair to the greater trochanter to a side-to-side capsular repair was associated with a decreased rate of dislocation in primary THA through a posterior approach.

Postoperative Failure Frequency of Short External Rotator and Posterior Capsule With Successful Reinsertion After Primary Total Hip Arthroplasty: An Ultrasound Assessment

BACKGROUND

The reinsertion of the short external rotators and posterior capsule to the greater trochanter in the posterolateral approach has been considered an effective strategy to reduce the risk of dislocation. However, during clinical practice, no verification and monitoring of the status of such reinsertions is carried out. The objective of this study is to estimate the frequency of postoperative failure with successful reinsertion of the short external rotator and posterior capsule of the hip through ultrasound after primary total hip arthroplasty (THA) using the posterolateral approach.

METHODS

A prospective observational study was conducted involving patients with primary total hip arthroplasty via posterolateral approach in which reinsertion of hip's short external rotators and posterior capsule were successful reinserted during surgery from January to December 2019. The status of the reinsertion was assessed with an ultrasound between the 6 and 8 weeks after surgery. Reinsertion failure was considered when the reinserted structures were not fully visualized in the ultrasound during internal and external rotation.

RESULTS

Sixty-eight patients were included in this study (mean age: 58.7 ± 13.8 years; 44.1% (30) women). The incidence of failure of the reinsertion of short external rotators and posterior capsule was 16.2% (n = 11) (95% confidence interval 9.3-26.7). A postoperative increased femoral offset was found more frequently in cases with failure (36.4% vs 17.5%); a similar trend was observed in the leg length discrepancy (36.4% vs 22.8%). However, these differences were not statistically significant (P > .05).

CONCLUSION

Between the 6th and 8th postoperative week, approximately 2 of the 10 short external rotator and posterior capsule reinsertions fail in cases with successful intraoperative repair using absorbable suture. This estimate is comparable and even lower than previous reports.

EVIDENCE LEVEL

II, Prospective Observational Study.

Transosseous versus transmuscular repair of the posterior soft tissue in primary hip arthroplasty: a meta-analysis

Background

During the posterior approach, it has been shown that a significant reduction in dislocation rate can be achieved with the repair of the posterior soft tissue. However, no consensus exists about the best way to perform this repair. This review aimed to compare the transosseous with transmuscular repair of the posterior soft tissue in total hip arthroplasty (THA).

Methods

We conducted a meta-analysis to identify studies involving transosseous versus transmuscular repair of the posterior soft tissue in THA in electronic databases, including Web of Science, Embase, PubMed, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CBM, CNKI, VIP, Wanfang database, up to July 2020. Finally, we identified 1417 patients (1481 hips) assessed in seven studies.

Results

Compared with transmuscular repair, transosseous repair resulted in less incidence of dislocation (P = 0.003), less blood loss during operation (P < 0.00001) and lower VAS score within 3 months (P = 0.02). There were no significant differences in terms of trochanteric fracture rate (P = 0.56), Harris hip score at 3 months (P = 0.35) and 6 months (P = 0.89), VAS score within 6 months (P = 0.53), and operation time (P = 0.70) between two groups.

Conclusion

The lower dislocation rate, less blood loss, and lower VAS scores after operation supported transosseous repair's superiority to transmuscular repair. Besides, no additional medical cost and operating time were associated with transosseous repair compared with transmuscular repair. Hence, we recommend that transosseous repair be chosen first by orthopedists when performing reconstruction of the posterior soft tissue in THA via a posterolateral approach. Given the relevant possible biases in our meta-analysis, we required more adequately powered and better-designed RCT studies with long-term follow-up to reach a firmer conclusion.

Overview of Randomized Controlled Trials in Primary Total Hip Arthroplasty (34,020 Patients): What Have We Learnt?

Aim:

To provide an overview of randomized controlled trials (RCTs) in primary total hip arthroplasty summarizing the available high-quality evidence.

Materials and Methods:

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA), we searched the Cochrane Central Register of Controlled Trials (2020, Issue 1), Ovid MEDLINE, and Embase. We excluded nonrandomized trials, trials on neck of femur fractures or revision surgery, systematic reviews, and meta-analyses. Trials that met our inclusion criteria were assessed using a binary outcome measure of whether they reported statistically significant findings. These were then classified according to the intervention groups (surgical approach, fixation, and component design use, among others).

Results:

Three hundred twelve RCTs met the inclusion criteria and were included. The total number of patients in those 312 RCTs was 34,020. Sixty-one RCTs (19.5%) reported significant differences between the intervention and the control groups. The trials were grouped into surgical approach 72, fixation 7, cement 16, femoral stem 46, head sizes 5, cup design 18, polyethylene 25, bearing surfaces 30, metal-on-metal 30, resurfacing 20, navigation 15, robotics 3, surgical technique 12, and closure/drains/postoperative care 13 RCTs.

Discussion:

The evidence reviewed indicates that for the vast majority of patients, a standard conventional total hip arthroplasty with a surgical approach familiar to the surgeon using standard well-established components and highly cross-linked polyethylene leads to satisfactory clinical outcomes. This evidence also offers arthroplasty surgeons the flexibility to use the standard and cost-effective techniques and achieve comparable outcomes.

Modified osteotomy of posterolateral overhanging part of the trochanter via posterior approach for hip arthroplasty: an anatomical study

Backgroud

The osteotomy of the posterolateral overhanging part (PLOP) of the greater trochanter via posterior approach has been used for the hip arthroplasty for decades with good results. However, the osteotomy method remains undefined and the precise adjacent structures around PLOP have not been reported. The purpose of this study was to present a modified PLOP osteotomy approach and perform a detailed study of the topographic and surgical anatomy of the PLOP.

Methods

The peri-PLOP soft tissue and the bony parameters were measured using 10 cadavers with 20 hips and 20 skeletal hip specimens, respectively.

Results

A 1.8-cm vertical osteotomy did not jeopardize the femoral neck, and a 1.8-cm wide bone block did not damage the insertions of the short external rotators. The average distances between the most distal branch of the superior gluteal nerve/artery and the 1.8-cm point of the greater trochanter were 5.70 ± 0.66 cm and 6.33 ± 0.56 cm, respectively.

Conclusion

For osteotomy of the PLOP, we suggested that the width of the upper side from the lateral to medial greater trochanter should be 1.8 cm, depth of vertical osteotomy should be 1.8 cm, and length of the posterior edge should be 4 cm. Obturator externus tendon should be kept within the bone block of osteotomy. The proximal extension of the gluteus medius muscle split should be limited to 5.5 cm at the 1.8 cm-point of the greater trochanter.

Level of evidence

Prospective comparative study Level II.

Comparison of Two Posterior Soft Tissue Repair Techniques to Prevent Dislocation after Total Hip Arthroplasty via the Posterolateral Approach

BACKGROUND

Although the posterolateral approach is considered to carry a higher early dislocation rate after total hip arthroplasty, posterior soft tissue repair techniques make up for this limitation. Through-bone and through-tendon repair techniques are the two most commonly used techniques. This study aimed to comprehensively compare these techniques and give more evidence-based references for orthopedists. Methods: This retrospective study enrolled 87 patients who underwent posterior soft tissue repair with total hip arthroplasty via the posterolateral approach. The posterior capsular and external rotators were reconstructed to the greater trochanter through drill holes (through-bone, n = 46) or gluteus medius tendon (through-tendon, n = 41). Early dislocation rate, repair-related complications, postoperative pain (visual analog scale, VAS), hip joint function (Harris Hip Scale, HHS), patient satisfaction, and operation-related indexes were evaluated. Results: The discrepancy in early dislocation between the two cohorts was not statistically significant. Operation-related indexes were not significantly different between the two cohorts, except for the postoperative drainage volume (229.46 mL vs. 172.07 mL, p=.013). No patient sustained greater trochanteric fracture and sciatic nerve injury. Each group achieved significant improvements in HHS and VAS scores compared with preoperative values. No statistically significant discrepancy was found in HHS scores between the two groups at the same period, while VAS scores were significantly lower in the through-bone group at 1 week (4.93 vs. 5.68, p=.026) and 1 month (1.72 vs. 1.99, p=.038) after surgery. Higher patient satisfaction was observed in the through-bone group. Conclusions: Although no statistical discrepancy in the early dislocation rate between through-bone and through-tendon repair techniques was observed, lower pain scores and higher patient satisfaction supported the former. We recommend that through-bone repair technique should be chosen first by orthopedists when performing reconstruction of the posterior soft tissue in total hip arthroplasty via a posterolateral approach.