The posterior approach in THR: assuring capsular stability

Systematic evaluation of the degree of joint amnesia in patients after total hip arthroplasty with direct anterior approach (DAA) compared with posterior approach (PA)

OBJECTIVE

A comparative study of joint amnesia in patients undergoing total hip arthroplasty with the direct anterior approach and posterior approach was conducted through a comprehensive evaluation.

METHODS

The literature on joint amnesia in postoperative patients who underwent total hip arthroplasty by the direct anterior approach and the posterior approach was systematically searched in PubMed, Embase, Web of Science, Cochrane Library, CNKI, CBM, Wanfang, and VIP databases from the time of library construction until February 13, 2023. Meta-analysis was performed using RevMan 5.3 software after independent searching, screening of the literature, data extraction, and quality assessment of the included studies by two investigators in strict accordance with the guidelines for conducting meta-analyses.

RESULTS

A total of one RCT and six cohort studies were included in this meta-analysis. Meta-analysis results indicated that at 1 month postoperatively (MD = 2.08, 95% CI (0.20, 3.96), P = 0.03), 3 months (MD = 10.08, 95% CI (1.20, 18.96), P = 0.03), and 1 year (MD = 6.74, 95% CI (1.30, 12.19), P = 0.02), DAA total hip arthroplasty was associated with better FJS compared to PA at 1 year postoperatively. However, there was no statistical significance in FJS between the two groups at 5 years postoperatively (MD = 1.35, 95% CI (- 0.58, 3.28), P = 0.17).

CONCLUSION

Current evidence suggests that the degree of joint amnesia after THA for DAA was not found to be superior to that of PA. Further, these findings require confirmation by including a larger number of high-quality randomized controlled studies.

STUDY DESIGN

Systematic review; Level of evidence, 3.

Joint awareness among total hip arthroplasty patients operated through anterior approach versus posterior approach: a systematic review and meta-analysis

PURPOSE

The aim of this systematic review and meta-analysis was to compare joint awareness in patients who underwent total hip arthroplasty (THA) via the anterior approach (AA) versus the posterior approach (PA). The hypothesis was that patients who underwent THA via AA would have better forgetfulness of the artificial joint.

METHODS

A comprehensive search of major literature databases and bibliographic details was conducted to identify studies evaluating the forgotten joint score (FJS-12) in total hip arthroplasty (THA) patients operated through the anterior approach (AA) and posterior approach (PA). Out of 234 studies identified, seven studies met the inclusion criteria for review. The Newcastle-Ottawa Scale was used to evaluate the quality of evidence and the risk of bias in the included studies. The FJS-12 was evaluated at three months, one year, and beyond 2 years.

RESULTS

The mean FJS-12 at > 2 years was 82.03 in the AA group and 80.32 in the PA group. The forest plot analysis (n = 819 patients) revealed no significant difference in FJS-12 score between these two approaches (MD 2.13, 95% CI [- 1.17, 5.42], p = 0.21; I2 = 60%). However, the joint awareness was significantly lesser in the AA group at 3 months (MD 12.56, 95% CI [9.58, 15.54], p < 0.00001, I2 = 0%) and 1 year (MD 9.55, 95% CI [7.85, 11.24], p < 0.0001, I2 = 0%).

CONCLUSIONS

After analyzing the available literature, it was found that THA patients operated through the AA approach have significantly lower joint awareness than those operated through the PA approach in the first year of surgery. However, there is no significant difference in joint awareness between these two approaches after 2 years.

LEVEL OF EVIDENCE

III.

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 short external rotators dissection during the posterior approach in total hip arthroplasty did not change the blood flow

OBJECTIVES

The posterior approach in total hip arthroplasty (THA) often requires dissection of the short external rotators (SERs), which could increase the postoperative dislocation rate. The reattachment of the dissected SERs has been reported to reduce the dislocation rate, while such repair generally causes progression of muscle atrophy. 1 of the suggested causes of atrophy is reduced blood flow to the repaired SERs. The present study aimed to measure the blood flow of the SERs before dissection (pre-tenotomy) and after reattachment (post-reattachment) during the posterior approach in THA.

METHODS

This prospective study included 26 patients who underwent THA via the posterior approach. A laser-Doppler rheometer was used to measure the blood flow in the following SERs at the time of pre-tenotomy and post-reattachment: the piriformis muscle (PM), superior gemellus (SG), inferior gemellus (IG), obturator internus (OI), and subcutaneous tissue as a control.

RESULTS

The average pre-tenotomy and post-reattachment blood flows (mL/minutes/100 g) were: 1.90 ± 0.28 and 1.92 ± 0.40 in the PM, 1.94 ± 0.20 and 1.99 ± 0.39 in the SG, 1.91 ± 0.21 and 1.94 ± 0.30 in the IG, 1.93 ± 0.22 and 1.98 ± 0.36 in the OI, and 1.94 ± 0.24 and 1.87 ± 0.38 in the subcutaneous tissue. The pre-tenotomy and post-reattachment blood flows did not show significant difference in any muscle.

CONCLUSIONS

Laser-Doppler blood flow measurements showed that the blood flow is preserved, even when the SERs are dissected and reattached in THA via the posterior approach.

The Effect of Total Hip Arthroplasty Surgical Technique on Postoperative Muscle Atrophy

A variety of surgical approaches are used for total hip arthroplasty (THA). Controversy still exists regarding whether the direct anterior approach truly minimizes muscle damage. The purpose of this study was to determine the effect of surgical approach for THA on muscle atrophy quantified through magnetic resonance imaging (MRI). The study included 25 hips in patients with a mean age of 64.72±8.35 years who underwent a primary unilateral THA for severe osteoarthritis. Patients were grouped according to surgical approach: direct anterior (n=9), direct lateral (n=9), and posterior (n=7). Magnetic resonance images were collected at the 24-week postoperative time point to assess atrophy/fatty infiltration of the hip musculature. All MRIs were assessed by a fellowship-trained radiologist who was blinded to all clinical information. There were no significant differences preoperatively and 1 year postoperatively between the surgical approach groups in terms of patient-reported outcome measures (P>.05). Significant differences in fatty infiltration differences between surgical approaches were observed in the gluteus medius, gluteus minimus, iliacus, obturator externus, obturator internus, pectineus, psoas, quadratus femoris, sartorius, and vastus intermedius (P<.05). The direct anterior approach to THA resulted in less atrophy of the hip musculature compared with a direct lateral or posterior approach; however, there were no differences in patient-reported clinical outcome scores at 1 year between the surgical approaches. [Orthopedics. 2020;43(6):361-366.].

Forgotten Joint Score in THA: Comparing the Direct Anterior Approach to Posterior Approach

BACKGROUND

The direct anterior approach (DAA) in total hip arthroplasty (THA) has gained popularity because of potential decreased postoperative pain and quicker recovery after surgery in comparison to the posterior approach (PA). With a growing focus on patient-reported outcome (PRO) measurements after surgery, we sought to determine if one approach led to better PRO scores as determined by the Forgotten Joint Score-12 (FJS-12) questionnaire.

METHODS

A retrospective chart review of primary THAs between September 2016 and September 2019 at a single academic hospital was conducted. Demographic and clinical data in addition to FJS-12 scores were collected. Two groups were created based on THA approach. Frequency rates, means, and standard deviations were used to describe baseline patient characteristics. Differences in demographic data were accounted for using linear regression models.

RESULTS

A total of 1469 cases were identified, with 830 using the DAA and 639 the PA. Significant demographic differences were observed between the 2 groups. However, when controlling for this, there were no differences in FJS-12 scores between approaches at 1 and 1.75 years (P = .232 and P = .486, respectively). At 12 weeks, DAA patients had higher satisfaction (59.21 vs 46.8; P = .006). When controlling for surgeon case volume, no differences in FJS-12 were observed at any of the time points (P = .536, P = .452, and P = .967, respectively) CONCLUSION: DAA THA patients trended toward better PRO scores than their PA counterparts. However, when controlling for surgeon case volume, no differences were observed, which suggests that surgeon case volume and experience have an important effect on patient satisfaction and FJS-12 scores.

Does Surgeon Fellowship Training Influence Outcomes in Hemiarthroplasty for Femoral Neck Fracture?

BACKGROUND

The aim of this study is to compare the outcomes (90 days and 1 year) of patients with femoral neck fracture undergoing hemiarthroplasty by surgeons with different fellowship training: trauma, arthroplasty, and general orthopedics.

METHODS

This study is a retrospective review of consecutive patients undergoing hip hemiarthroplasty for femoral neck fracture from 2010 to 2018. Comorbidities, perioperative details, demographics, injury variables, and time-to-surgery were compared between the fellowship training cohorts, in addition to outcomes including dislocation, periprosthetic joint infection, and mortality at 90 days and 1 year.

RESULTS

A total of 298 hips with an average age of 77.8 years underwent hemiarthroplasty for femoral neck fracture. Arthroplasty surgeons had a significantly shorter operative duration (82 minutes, P = .0014) and utilized the anterior approach more frequently (P < .0001). The general orthopedists had a significantly increased total surgical complication risk compared to both the arthroplasty and trauma fellowship-trained cohorts at both 90 days (11.8% vs 1.6% vs 3.9%, P = .015) and 1 year (18.2% vs 4.9% vs 7.1%, P = .008). The overall mortality risk was 11.7% at 90 days and 22.8% at 1 year. When adjusted for covariates, including comorbidities, gender, age, and preoperative walking capacity, both the arthroplasty fellowship-trained cohort (odds ratio 0.381, 95% confidence interval 0.159-0.912, P = .030) and the general orthopedist cohort (odds ratio 0.495; 95% confidence interval 0.258-0.952, P = .035) had reduced risk of 1-year mortality compared to the trauma fellowship-trained cohort.

CONCLUSION

Hemiarthroplasty performed for femoral neck fractures may result in fewer complications when performed by arthroplasty fellowship-trained surgeons. An arthroplasty weekly on-call schedule and adjusted institutional protocols may be utilized to improve outcomes and reduce complications.

LEVEL OF EVIDENCE

Level II, retrospective cohort.

Preservation technique of the piriformis tendon is superior to reattachment technique in terms of contiguity and muscle atrophy: using magnetic resonance imaging

PURPOSE

The preservation technique of the piriformis tendon during the posterolateral approach in total hip arthroplasty (THA) is reportedly superior to the reattachment technique in terms of dislocation. However, the long-term effects of preservation of the piriformis tendon during THA remain unknown. In this study, we evaluated the contiguity of the piriformis/conjoined tendon and atrophy of the piriformis/internal obturator muscle during a long-term postoperative follow-up using magnetic resonance imaging (MRI).

METHODS

We retrospectively evaluated 48 patients with available MRI. The 48 patients were classified into a P group ( n = 29), in which the piriformis tendon was preserved, and an R group ( n = 19), in which the piriformis was reattached after sectioning. The mean follow-up duration was 45.9 months. The contiguity of the piriformis/conjoined tendon and atrophy of the piriformis/internal obturator muscle were evaluated in all patients.

RESULTS

The piriformis tendon remained attached to the greater trochanter in all P-group patients and 68.4% of R-group patients. The mean piriformis muscle atrophy ratios were 15.9% ± 21.1% in the P group and 41.6% ± 19.1% in the R group ( p < 0.001). The conjoined tendon repair remained intact in 72.4% of P-group patients and 36.8% of R-group patients ( p < 0.05). The mean internal obturator muscle atrophy ratio was 31.4% ± 26.2% in the P group and 50.4% ± 19.1% in the R group ( p < 0.05). No postoperative pulmonary embolism, wound infection, deep infection, or hip dislocation occurred.

CONCLUSIONS

In our study, we suggest that the preservation technique of the piriformis tendon is superior to the reattachment technique in terms of contiguity and muscle atrophy.

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

PURPOSE

Although the posterolateral approach for hip arthroplasty is popular and has numerous advantages, it has been known to have a propensity for dislocation. The repair of short external rotator muscles with capsule is important for reducing dislocation. The purpose of this study is to investigate the incidence of suture failure, dislocation, and time to failure for two repair techniques for posterior soft tissue repair during total hip arthroplasty.

METHODS

In this study of 167 total hip arthroplasties in 159 patients, we reattached the short external rotator tendon with posterior capsule to the greater trochanter transosseously (tendon-to-bone, 87 hips) or the gluteus medius tendon (tendon-to-tendon, 80 hips). Radiopaque markers were attached to each suture side < 1.2 cm apart. The distance between the markers was radiographically measured at variable time points postoperatively. Failure was defined by a distance between markers of ≥ 2.5 cm or marker invisibility. The mean follow-up period was 28.8 (12-45) months.

RESULTS

Suture failure was observed less frequently in the tendon-to-bone group (18.4%) than in the tendon-to-tendon group (65%; p < 0.001). Failure mostly occurred within two weeks post-operatively: 93.8% for tendon-to-bone repair (p < 0.001) and 90.4% for tendon-to-tendon repair (p = 0.025). The dislocation rate was significantly higher in the tendon-to-tendon group (7. vs 1.1%; p = 0.041). A significant correlation was observed between suture failure and dislocation (p = 0.013).

CONCLUSIONS

Tendon-to-bone repair is superior to tendon-to-tendon repair based on lower suture failure and dislocation rates.

Posterior versus direct anterior approach in total hip arthroplasty: difference in patient-reported outcomes measured with the Forgotten Joint Score-12

INTRODUCTION

When the postoperative outcome of primary total hip arthroplasty (THA) was compared with the direct anterior approach (DAA) and the posterior approach (PA), there was no significant difference of the clinical outcome at 6 months to 1 year after surgery in many studies. This study was performed to compare the medium-term outcome of THA via the DAA or PA and clarify which approach achieves better quality of life (QOL).

METHODS

We investigated 61 hips receiving primary THA (30 via DAA and 31 via PA), using hip function scores such as the Harris Hip Score (HHS) and patient-reported outcomes such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS).

RESULTS

The mean duration of postoperative follow-up was 36.8 months in the DAA group and 40.5 months in the PA group. There was no difference in preoperative or postoperative HHS between the two groups. Although there was no difference of postoperative WOMAC and JHEQ, the postoperative FJS-12 score was significantly higher in the DAA group than in the PA group (75.2 ± 15.9 versus 60.1 ± 24.4, p = 0.01).

CONCLUSION

When forgetting the artificial joint in daily life is the target, better QOL can be achieved by performing THA via the DAA.

Posterior Soft Tissue Repair After Primary THA is Durable at Mid-term Followup: A Prospective MRI Study

BACKGROUND

The enhanced posterior soft tissue repair has reduced the frequency of dislocation after primary THA performed through the posterolateral approach. However, the long-term integrity of the repair is unknown and could influence surgeon choice regarding surgical technique and THA approach.

QUESTIONS/PURPOSES

We asked: (1) What is the durability of the enhanced posterior soft tissue repair at a minimum of 49 months using MRI to evaluate soft tissue to bone integrity? (2) How does the appearance of the posterior soft tissues change during this time? (3) Are there patient characteristics associated with the long-term imaging appearance of the posterior repair?

METHODS

All patients without a contraindication for MRI who were undergoing unilateral primary uncemented THA through a posterior approach between February and May 2005 were eligible for inclusion. Ninety percent consented to participate (36 of 40 patients), and 30 patients were followed prospectively with MRI postoperatively and again at 3 months; of those, 22 (73%; 12 men, 10 women) completed the study by having another MRI study at a minimum of 49 months (mean, 51 months; range, 49-59 months). Each patient underwent metal-artifact-reduction sequence MRI to evaluate the integrity of the posterior soft tissues, which had been repaired anatomically during primary THA at a minimum of 4 years earlier. The results were compared with those of prior MR images obtained immediately after surgery and at 3 months postoperatively. All patients were given a self-reported modified Harris hip score at the time of the most recent MRI study (maximum score = 81).

RESULTS

At latest followup, 21 of 22 (96%) patients had a posterior capsule in contact with bone, and 21 of 22 (96%) had an intact quadratus femoris. Twenty-one patients (96%) had soft tissue or a scar from the piriformis and conjoined tendons in continuity with bone. In these cases, the interface between the piriformis and conjoined tendons and the greater trochanter observed immediately postoperatively and at 3 months postoperatively became filled with hypointense tissue, with signal characteristics similar to tendon. Time from surgery was most associated with changes in native tendon-to-bone distances (p < 0.001) and MRI signal intensity of the repair (p < 0.001).

CONCLUSIONS

At followup of just more than 4 years, the posterior capsule and quadratus femoris most often were healed to bone. In the majority of patients, scar tissue between the piriformis and conjoined tendons and bone matured to achieve orientation and signal intensity resembling native tendon. We believe the enhanced posterior soft tissue repair facilitates this process. Our results provide a plausible explanation for improved postoperative stability observed in patients receiving an enhanced soft tissue repair compared with those in whom a repair is not performed.

LEVEL OF EVIDENCE

Level IV, therapeutic study.