Anterior iliopsoas impingement and tendinitis after total hip arthroplasty

Accuracy of ultrasound-guided iliopsoas tendon injection after total hip arthroplasty: a retrospective observational study

PURPOSE

To describe and characterize the accuracy and benefit of a technique for performing ultrasound-guided needle placement for iliopsoas peritendon or bursa injections as an alternative method to fluoroscopic guidance.

MATERIALS AND METHODS

Patients with a history of total hip arthroplasty who were referred by their orthopedic surgeon for iliopsoas peritendon or bursa corticosteroid injection for iliopsoas impingement syndrome between June 2017 and December 2019 were eligible for inclusion. Of these patients, 19 received a total of 26 ultrasound-guided needle placement followed by confirmatory fluoroscopic guidance prior to injection. Pre-injection and post-injection VAS scores were collected to monitor pain. Additionally, the patients were followed for 6 months via chart review after their injection to assess for complications, need for repeat injections, and progression to surgical intervention. The accuracy of a longitudinal in-plane distal to proximal approach to ultrasound guided needle placement was then evaluated.

RESULTS

Ultrasound guided needle placement using a longitudinal in-plane distal to proximal approach demonstrated spread of contrast material in the intended anatomic location with fluoroscopic confirmation in patients who underwent iliopsoas peritendon or bursa injection post total hip arthroplasty.

CONCLUSION

Ultrasound guided needle placement using a longitudinal in-plane distal to proximal approach can be an effective alternative technique for diagnostic or therapeutic iliopsoas peritendon injection in patients with total hip arthroplasty.

Arthroscopic and endoscopic techniques for iliopsoas release in THA are safe and effective: a systematic review of the literature

BACKGROUND

Hip replacement surgery is highly effective in relieving pain and improving mobility in patients with various hip conditions. However, some patients develop groin pain after surgery, often due to iliopsoas impingement (IPI), which can be challenging to diagnose. Conservative treatments are initially recommended, but when these are not effective, surgical options may be considered. This study aims to evaluate the clinical outcomes, success and failure rates, revision rates, and complications associated with arthroscopic and endoscopic surgery for IPI, thereby providing a comprehensive understanding of the effectiveness and risks of these surgical interventions.

MATERIALS AND METHODS

A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including a thorough search of five main databases: PubMed, Scopus, Embase, Medline, and Cochrane. Eligible articles were meticulously evaluated according to predefined criteria for levels of evidence (LoE), with retrospective studies assessed using the Coleman Methodology Score (mCMS). This systematic review was registered in the International Prospective Registry of Systematic Reviews (PROSPERO).

RESULTS

Among the 16 included studies, 431 patients with 434 hips underwent either endoscopic or arthroscopic tenotomy. Both techniques showed favorable outcomes, with arthroscopic tenotomy demonstrating slightly higher success rates than endoscopic tenotomy. Common complications included mild pain and occasional infections, with recurrence observed in some cases. Both techniques offer direct visualization of prosthetic components and potential preservation of psoas function.

CONCLUSIONS

Arthroscopic and endoscopic iliopsoas tenotomy are effective treatments for alleviating symptoms and improving hip function in patients with IPI post-total hip arthroplasty (THA).

LEVEL OF EVIDENCE

IV.

Quantifying cup overhang after total hip arthroplasty: standardized measurement using reformatted computed tomography and association of overhang distance with iliopsoas impingement

OBJECTIVES

Currently, there is no standardized measurement method for evaluating cup overhang (CO) in patients undergoing total hip arthroplasty (THA). We propose a novel, standardized method of measuring overhang distance in patients following primary total hip arthroplasty (THA) on computed tomography (CT) images after multiplanar reformation and compare it to a previously proposed measurement method on sagittal CT images.

MATERIALS AND METHODS

This retrospective study included patients who underwent primary THA with an anterior approach. Patients with cup overhang (CO) and iliopsoas impingement (IPI) were identified by clinical and imaging data. Uncorrected overhang distance (ODu) was evaluated on orthogonal sagittal CT images while corrected overhang distance (ODc) was evaluated on reformatted sagittal CT images corrected for pelvic rotation and aligned with the plane of the cup face.

RESULTS

Out of 220 patients with THA, 23 patients (10.4%) with CO and 16 patients (7.3%) with IPI were identified. CO was significantly associated to IPI (p < 0.001). The inter- and intrareader agreement was almost perfect for ODc (κ = 0.822, κ = 0.850), whereas it was fair and moderate for ODu (κ = 0.391, κ = 0.455), respectively. The discriminative ability of ODc was excellent (area under the curve (AUC) = 0.909 (95% confidence interval (CI) 0.784-1.000)) in the receiver operating characteristic analysis. Conversely, AUC for ODu was poor, measuring 0.677 (95% CI 0.433-0.921).

CONCLUSION

We implemented a novel measurement method for CT images reformatted at the plane of the cup face to assess overhang distance in patients with CO following THA.

CLINICAL RELEVANCE STATEMENT

While further validation is necessary, the proposed method is characterized by its high reproducibility and might be used to predict the occurrence of iliopsoas impingement in patients with cup overhang following total hip arthroplasty.

KEY POINTS

• A novel, standardized method of measuring cup overhang distance in patients following primary total hip arthroplasty on CT images is proposed. • Cup overhang was associated to iliopsoas impingement. The proposed method was reproducible and showed excellent prediction of iliopsoas impingement in patients with cup overhang. • This method can be implemented in clinical practice when assessing CT images of patients with cup overhang for iliopsoas impingement.

Pelvic Roll Back Can Trigger Functional Psoas Impingement in Total Hip Arthroplasty

In most cases, impingement of the iliopsoas tendon after total hip arthroplasty is caused by acetabular component retroversion. The present case report describes a patient with functional iliopsoas impingement following total hip arthroplasty. With increasing flexibility of the hip joint after surgery, the functional adjustment to the stiff thoracolumbar spine in this patient with diffuse idiopathic skeletal hyperostosis resulted in progressive pelvic roll back. This roll back resulted in a functional iliopsoas impingement as the psoas tendon travels over the front of the pecten ossis pubis. Since excessive roll back is usually also addressed in primary total hip arthroplasty by decreasing anteversion of the acetabular component, surgeons should be aware to avoid the combination of roll back and decreased anteversion and their potential impact on iliopsoas impingement.

Endoscopic Tendon Release for Iliopsoas Impingement After Total Hip Arthroplasty-Excellent Clinical Outcomes and Low Failure Rates at Short-Term Follow-Up

PURPOSE

To investigate the clinical effectiveness of endoscopic iliopsoas tendon release (IPR) at the lesser trochanter (LT) in patients with iliopsoas impingement (IPI) after total hip arthroplasty (THA).

METHODS

Between November 2017 and March 2021, a consecutive series of 36 patients were treated with endoscopic IPR for diagnosed IPI. Patients included had acetabular cup position confirmed by functional imaging (OPS, Corin, Pymble, NSW), typical clinical symptoms of IPI, and a positive response to diagnostic injection. Clinical assessment included validated patient-reported outcome measures (PROMs) along with hip flexion strength and active range of motion at different time marks up to 2-year follow-up, as well as surgical complications.

RESULTS

Overall, 36 consecutive patients (11 males) with a mean age of 62 ± 12 years were included. All patients had failed nonoperative management. Dynamic computed tomography assessment was available in 89% of the patients, edge loading was reported in 10%, and variable cup overhang was reported in 50%. Clinically, PROMs were significantly improved at every time mark when compared with preoperative values (P < .001), showing the biggest improvement within the first 4 weeks after surgery. At the 6-month follow-up, peak isometric hip flexion strength on the operated side was 20% lower than the contralateral side (P < .001). Failure rate of the procedure was 2.8% (1 case). Linear regression showed no association between cup overhang and clinical outcomes.

CONCLUSIONS

Endoscopic IPR at the LT is a safe and reproducible technique associated with significant and immediate improvement in pain, functional outcomes, and high patient satisfaction. With minimal short-term weakness, no complications, and only a single revision, even in cases with cup malposition and/or edge loading, we believe that endoscopic IPR can be considered as one of the first-line operative options in patients with symptomatic IPI, irrespective of component position.

LEVEL OF EVIDENCE

Level IV, case series.

Arthroscopic Iliopsoas Fractional Lengthening After Total Hip Arthroplasty: Using the Iliopsoas Air Bursogram Technique to Hit the Target

Iliopsoas tendinitis following total hip arthroplasty has been linked to retroverted acetabular cup position with associated anterior overhang. For severely malpositioned components, preferred treatment is in the form of revision arthroplasty. However, for a substantial number of cases, iliopsoas tendinitis as well as associated pain and disability are observed in the presence of modest acetabular overhang. In such cases, patients may benefit substantially from arthroscopic iliopsoas fractional lengthening. Given altered postarthroplasty anatomy, we present an arthroscopic approach employing an iliopsoas air bursogram. In such a way, safe and predictable access can be provided for efficient tendon lengthening without capsular violation or inadvertent instrumentation of the nearby medial neurovascular bundle.

Ultrasound-Guided Iliopsoas Bursal Injections for Management of Iliopsoas Bursitis After Total Hip Arthroplasty

BACKGROUND

Iliopsoas tendonitis can cause persistent pain after total hip arthroplasty (THA). Nonoperative management of iliopsoas tendonitis includes anti-inflammatory drugs and image-guided corticosteroid injections. This study evaluated the efficacy of ultrasound-guided corticosteroid injections (US-CSIs) for iliopsoas tendonitis following THA.

METHODS

We retrospectively reviewed 42 patients who received an US-CSI for iliopsoas tendonitis after primary THA between 2009 and 2020 at a single institution. Outcomes including reoperation, groin pain at last follow-up, additional intrabursal injection, and Harris Hip Score (HHS) were evaluated at a minimum of 1 year. Cross-table lateral radiographs (36 patients) or computed tomography scans (6 patients) were reviewed to determine if anterior cup overhang was present, indicating a mechanical etiology of iliopsoas tendonitis. Descriptive statistics and univariate comparison of HHS preinjection and postinjection were performed, with alpha < 0.05.

RESULTS

Among the 22 patients who did not have cup overhang, four (18.2%) had persistent groin pain at mean follow-up of 40 months (range, 14-94) after US-CSI. Three patients had a second injection; none had groin pain at most recent follow-up. No patients required acetabular revision. Mean HHS improved from 74 points (range, 52-94 points) to 91 points (range, 76-100 points; P < .001) at last follow-up. Among the 20 patients who had anterior cup overhang, five underwent acetabular revision after only temporary pain relief from injection. Groin pain was resolved in all revised patients at mean follow-up of 43 months (range, 12-60) after revision. Of the remaining 15 patients, five had persistent groin pain at mean follow-up of 35 months (range, 12-83). Mean HHS improved from 69 points (range, 50-96 points) preinjection to 81 (range, 56-98 points; P = .007) at last follow-up.

CONCLUSION

Resolution of groin pain was demonstrated in 78.6% of patients in the cohort; however, those who did not have acetabular overhang had higher rates of success. The overall revision rate was 11.9%. US-CSI appears to be safe and effective in the diagnosis and treatment of iliopsoas tendonitis following primary THA.

LEVEL OF EVIDENCE

Level IV, Therapeutic Study.

Endoscopic iliopsoas lengthening for treatment of recalcitrant iliopsoas tendinitis after total hip arthroplasty

Iliopsoas (IP) tendinitis from impingement upon the acetabular component after total hip arthroplasty (THA) has been treated with open and endoscopic IP tenotomy or acetabular component revision. This study describes the results of a consecutive series of patients treated with endoscopic IP tenotomy as a less invasive alternative. Twenty-eight patients with IP impingement after THA underwent endoscopic IP lengthening from 2012 to 2021 at a single-center academic institution. The follow-up of 24 of these patients was achieved with a mean follow-up of 7.6 months (range 1-28). Outcomes included the modified Harris Hip Score (mHHS), visual analog pain scale (VAS), satisfaction, component positioning and complications. Seventy-one percent of patients were satisfied or very satisfied after their operation. The median mHHS preoperatively was 57 (Interquartile range [IQR] 43-60) and postoperatively was 75 (IQR 66-92, P < 0.001). Clinically meaningful improvements in mHHS were seen in patients with VAS pain scores <5, cup prominence >8 mm, body mass index >30, and less than 2 years from their index THA. Two patients developed a deep infection 7 and 10 months postoperatively (neither related to the release), and one patient underwent open psoas release for persistent impingement. Endoscopic IP tenotomy is a safe and effective treatment for impingement after THA. Patients with cup prominence >8 mm, body mass index >30 and less than 2 years since their index THA may have more clinically meaningful improvements in pain and function.

The role of 3-dimensional preoperative planning for primary total hip arthroplasty based on artificial intelligence technology to different surgeons: A retrospective cohort study

Preoperative planning with computed tomography (CT)-based 3-dimensiona (3D) templating has been achieved precise placement of hip components. This study investigated the role of the software (3-dimensional preoperative planning for primary total hip arthroplasty [THA] based on artificial intelligence technology, artificial intelligence hip [AIHIP]) for surgeons with different experience levels in primary THA. In this retrospective cohort study, we included patients, who had undergone THA with the help of the AIHIP, and matched to patients, who had undergone THA without the help of the AIHIP, by age and the doctor who operated on them. The subjects were divided into 4 groups, senior surgeon (Chief of Surgery) with AIHIP group, senior surgeon without AIHIP group, junior surgeon (Associate Chief of Surgery) with AIHIP group and junior surgeon without AIHIP group. The general data, imaging index, clinical outcomes and accuracy of stem size prediction and cup size prediction were retrospectively documented for all patients. There was a significant difference in discrepancy in leg length (P = .010), neck-shaft angle (P = .025) and femoral offset (P = .031) between the healthy side and the affected side, operation duration (P < .001), decrease in hemoglobin (Hb) per 24 hours (P = .046), intraoperative radiation exposure frequency (P < .050) and postoperative complications (overall P = .035) among the patients in junior surgeon group. No significant differences were found between senior surgeon groups with respect to discrepancy in leg length (P = .793), neck-shaft angle (P = .088)and femoral offset (P = .946) between the healthy side and the affected side, operation duration (P = .085), decrease in Hb per 24 hours (P = .952), intraoperative radiation exposure frequency (P = .094) and postoperative complications (overall P = .378). The stem sizes of 95% were accurately estimated to be within 1 stem size, and 97% of the cup size estimates were accurate to within 1 cup size in senior surgeon group with AIHIP. A total of 87% stem sizes were accurately estimated to be within 1 stem size, and 85% cup sizes were accurate to within 1 cup size in junior surgeon group with AIHIP. In conclusion, our study suggests that an AI-based preoperative 3D planning system for THA is a valuable adjunctive tool for junior doctor and should routinely be performed preoperatively.

Relationship between iliopsoas muscle surface pressure and implant alignment after total hip arthroplasty: a cadaveric study

Iliopsoas impingement after total hip arthroplasty is caused by the implant irritating the iliopsoas muscle, but changes in the iliopsoas muscle have not been quantitatively evaluated. This study assessed changes in the surface pressure of the iliopsoas muscle when the implant alignment was varied. Total hip arthroplasty was performed in 10 fresh-frozen cadaveric hips. We evaluated the maximum and mean surface pressure of the iliopsoas muscle with the hip in 20° and 10° extension, the neutral position, and 10° flexion when the anterior cup protrusion length (ACPL), stem version, and stem offset were varied. When the ACPL was changed to 0, 3, and 6 mm in 20° extension, the maximum surface pressure was significantly increased for ACPL of 6 mm compared with 0 mm. Decreased stem anteversion resulted in a significant reduction in both the maximum and mean surface pressure compared with native anteversion from 20° extension to the neutral position. Increased stem offset resulted in significant increases in the maximum and mean surface pressure of the iliopsoas muscle compared with decreased stem offset in 20° extension. Not only large ACPL but also changes in stem version and offset affected the maximum surface pressure of the iliopsoas muscle.

Incidence and Risk Factors of Iliopsoas Tendinopathy After Total Hip Arthroplasty: A Radiographic Analysis of 1,602 Hips

BACKGROUND

Iliopsoas tendinopathy (IPT) can cause persistent groin pain and lead to dissatisfaction after total hip arthroplasty (THA). This study aimed to report the characteristics, incidences, risk factors, and treatment outcomes of IPT after THA.

METHODS

We reviewed primary THAs performed at a single institution between January 2012 and May 2018. Clinical and radiographic analyses were performed on 1,602 THAs (1,370 patients). Patient characteristics, component sizes, inclination and anteversion angles, and antero-inferior cup prominence (≥8 millimeters (mm)), were compared between the groups with and without IPT. Changes in teardrop to lesser trochanter distance were measured to estimate changes in leg length and horizontal offset caused by THA. Logistic regression models were used to identify the risk factors for IPT. IPT was identified in 53 hips (3.3%).

RESULTS

Patients with IPT had greater leg lengthening (12.3 versus 9.3 mm; P = .001) and higher prevalence of antero-inferior cup prominence (5.7 versus 0.4%; P = .002). There was no significant difference in inclination, anteversion, and horizontal offset change between the two groups. In multivariate analyses, greater leg lengthening, prominent acetabular cup, women, and higher body mass index were associated with IPT. All patients reported improvement in groin pain after arthroscopic tenotomy, while 35.7% with nonoperative management reported improvement (P < .001).

CONCLUSIONS

Symptomatic IPT occurred in 53 (3.3%) of the 1,602 primary THAs. Our findings suggest that leg lengthening as well as prominent acetabular cup in THAs can be associated with the development of IPT. Arthroscopic tenotomy was effective in relieving groin pain caused by IPT.

Arthroscopic Peripheral Compartment Iliopsoas Release for Iliopsoas Impingement After Primary Total Hip Arthroplasty

Anterior iliopsoas (IP) impingement after total hip arthroplasty is an underrecognized and continued cause for postoperative pain. There are multiple etiologies for this impingement from cup positioning and sizing to changes in the leg length, and offset must be evaluated to confirm no need for implant revision. Additionally, tension of the IP tendon can be increased in patients with diminished spinal mobility, either from prior fusion or with increasing age. Managing this surgically after failing conservative treatment options is best done arthroscopically to prevent additional large, open procedures that place the arthroplasty at unnecessary risk of infection and potential instability. In this article, we describe an arthroscopic technique using fluoroscopy to guide the release of the iliopsoas tendon from the peripheral compartment.

Arthroscopic iliopsoas tenotomy after total hip arthroplasty: safe method for the right patient

PURPOSE

To evaluate the outcome of arthroscopic treatment for iliopsoas impingement after total hip arthroplasty (THA) 2 years after surgery using patient reported outcomes (PROM).

METHODS

In this study 12 patients (13 hips) were included from a local hip arthroscopy registry. Patients completed web-based PROMs preoperatively and at a minimum of 2 years postoperatively. The PROMs included the International Hip Outcome Tool short version (iHOT-12), the Copenhagen Hip and Groin Outcome Score (HAGOS), the European Quality of Life-5 Dimensions Questionnaire (EQ-5D), the Hip Sports Activity Scale (HSAS) for physical activity level, the Visual Analog Scale (VAS) for overall hip function and a single question regarding overall satisfaction with the surgery.

RESULTS

The mean age was 64.4 years (±15.1SD), mean body mass index (BMI) was 26.6 (±4.3SD), mean follow-up time was 49.8 months (±25SD). Comparing PROMs preoperatively with 2-year follow up showed an improvement for many of the PROMs used. The PROMs scores were iHOT-12 (24.9 vs 34.5, p = 0.13), HAGOS subscales (symptoms 38.2 vs 54.5, p = 0.05; pain 36 vs 53, p = 0.04; sport 14.1 vs 35.1, p = 0.03; daily activity 31 vs 47.5, p = 0.04; physical activity 21.8 vs 24, p = 0.76; quality of life 24 vs 35, p = 0.03), EQ-VAS (57.9 vs 58, p = 0.08), EQ-5D (0.34 vs 0.13, p = 0.07) and VAS for overall hip function (43.1 vs 46.2, p = 0.14). In total, 10 out of the 12 patients (83%) were satisfied with the intervention.

CONCLUSION

Patients undergoing surgery for iliopsoas impingement after previous THA showed improved self-reported hip function where most patients were satisfied with treatment.

Cup Overhanging in Anatomic Socket Position or High Hip Center of Rotation in Total Hip Arthroplasty for Crowe III and IV Dysplasia: A CT-Based Simulation

Cup overhanging in total hip arthroplasty is a predisposing factor to iliopsoas impingement. In dysplastic hips, cup implantation was simulated in an anatomic hip center of rotation (AHCR) and in high hip center (HHCR). We sought to assess: (1) the percentage of prominent cups; (2) quantify the cup protrusion at different sites on frontal, axial and sagittal views. In 40 Crowe III-IV hips, using a 3D CT-based planning software, cup planning in AHCR and HHCR (CR height ≥ 20 mm) was performed for every hip. Cup prominence was assessed on every plane. HHCR cups were less anteverted (p < 0.01), less medialized (p < 0.001) and less caudal (p = 0.01) than AHCR sockets. AHCR cups were more frequently prominent on at least one plane (92.5% vs. 77.5%), with minimal agreement between the two configurations (k = 0.31, p = 0.07). AHCR cups protruded more than HHCR sockets in the sagittal (p = 0.02) and axial planes (p < 0.001). Axially, at the center of the cup, prominence 6−11 mm occurred in nine (22.5%) AHCR and one (2.5%) HHCR socket. In conclusion, while a routine high hip center should not be recommended, cup placement at a center of rotation height < 20 mm is associated with higher rates and magnitudes of anterior cup protrusion in severe dysplasia.

Localization of the ilioischial line on axial computed tomography images for preoperative planning of total hip arthroplasty

BACKGROUND

If the bony region indicating the ilioischial line is established on the preoperative axial computed tomography (CT) image, the distance between the simulated cup and the ilioischial line can be measured on this image so that the surgeon can use these data to define a more accurate preoperative two-dimensional (2D) template of total hip arthroplasty (THA). This study aimed to verify the hypothesis that on the CT axial image, the cortical bone area, indicated by the superimposition of a line (line α) with a perspective projection angle to the ilioischial line on radiography and tangent to the medial acetabular wall, is the cortical bone that represents the ilioischial line on radiography.

METHODS

Study 1: If the two measured distances (distance A' and distance B) are sufficiently equal, then the hypothesis can be supported. Distance A' was calculated by multiplying the distance A, between the ilioischial line and the medial margin of the metal cup after THA measured at the level of the hip joint center on the pelvic radiograph, by 0.91 to correct for radiographic magnification. Distance B was defined as the distance between the medial margin of the metal cup and line α on the axial CT image at the level of the hip joint center. These two distances were measured for all 51 hip joints included in the study. Study 2: The difference between distance A and distance A^# (distance A on the 2D template) was compared between the group containing 59 primary THAs in which distance B' was measured (distance B in the simulation) and the control group containing 59 primary THAs.

RESULTS

Study 1: The average distance for A' was 4.5 ± 2 mm, and the average distance for B was 4.7 ± 2.1 mm. The difference between distances A and B was 0.2 ± 0.2 mm. Study 2: The mean difference between distance A and distance A^# for the measurement and control groups was 1.8 ± 1.3 mm and 3.7 ± 2.4 mm, respectively (P < 0.001).

CONCLUSIONS

The ilioischial line is located in the bony region where line α intersects the medial acetabular wall with a maximum overlap on axial CT images.

Iliopsoas impingement after total hip arthroplasty: Does the CT-scan have any role? Our Algorithm proposal

Introduction

The first surgical option considered in managing iliopsoas impingement following THA is endoscopic/arthroscopic iliopsoas tenotomy, because of its low risk and minimal invasiveness. Acetabular revision is a much more aggressive surgery, recommended only in cases of substantial cup malposition. However, there are no clear indications for this procedure. The purpose of this article is to analyse the role of CT-scan measurement of acetabular cup positioning in a therapeutic algorithm for iliopsoas impingement.

Methods

In this retrospective observational study, we reviewed 25 patients treated for iliopsoas impingement following THA between 2011 and 2019. We studied acetabular cup positioning using CT-scan. We compared radiological parameters of patients who presented with significant clinical improvement with conservative treatment and with tenotomy against those who did not. Finally, we developed a proposed therapeutic algorithm.

Results

Forty-eight percent of patients presented a significant clinical improvement following conservative treatment. Patients who did not improve were found to have greater acetabular cup axial and sagittal overhang (p-values 0.016 and 0.003). These patients were considered for tenotomy. Of this group, those who did not improve with surgery (38%) showed greater axial overhang (p-value 0.005).

Conclusions

Conservative management should be the first line of treatment. In cases of non-operative treatment failure, axial acetabular cup overhang measured by CT-scan can be a useful tool in choosing between iliopsoas tenotomy or cup-revision surgery in selected cases of very severe acetabular malposition. A cut-off point of 10 mm of axial overhang is a reliable predictor of higher failure risk with iliopsoas tenotomy.

Diagnosis and Treatment of Musculotendinous Deficiencies of the Hip

Musculotendinous deficiencies related to iliopsoas tendinitis and abductor mechanism disruption following total hip arthroplasty (THA) are frequently under diagnosed and can be frustrating to surgeons and devastating to patients with painful THAs with normal appearing radiographs. Current peer-reviewed evidence is presented for diagnosis and treatment options for these two musculotendinous deficiencies. While these musculotendinous deficiencies are treatable, prevention during the primary THA is ideal, and special attention should be taken into consideration for optimized acetabular cup size and position, optimized hip biomechanics, and preservation and protection of the abductor tendon insertion to the greater trochanter.

Arthroscopic iliopsoas tenotomies: a systematic review of surgical technique and outcomes

PURPOSE

To evaluate the technique, results and complications of arthroscopic iliopsoas tenotomies either on native hips or total hip arthroplasty (THA).

METHODS

A systematic review was performed using 3 databases: PubMed, EMBASE and the Cochrane library from January 2000 to December 2018 in accordance with the PRISMA procedure. The literature search, data extraction and quality assessment were conducted by 2 independent reviewers. Surgical technique, clinical outcomes, recurrences and complication rate were evaluated.

RESULTS

Out of 115 articles reviewed, 20 articles concerned native hips and 8 articles THA. 3 levels of release were described. For native hips, the recurrence rate was higher for central compartment than peripheral or lesser trochanter releases. Complication rates were similar for hip arthroscopy but remained low in all series. Loss of strength was evaluated mainly using the MRC muscle scale. Most studies noted strength recovery. MRI analysis of muscle atrophy was greater for lesser trochanter than for central compartment release but unrelated to loss of strength. The complication rate was low for tenotomy after THA, heterotopic ossification being the most common complication.

CONCLUSIONS

Central compartment releases lead to the highest rate of recurrence due to incomplete release. Peripheral releases have a potential risk of vascular injury. The lesser trochanteric approach has the disadvantage of not having direct access to the joint. The main difficulty with THA lies in the diagnosis of cup/iliopsoas impingement. Diagnostic tests with infiltration should be made before iliopsoas release to prevent its failure. Cup protrusion of over 8mm is a potential indication for acetabular revision.

Results after arthroscopic treatment of iliopsoas impingement after total hip arthroplasty

BACKGROUND

A cause of groin pain after total hip arthroplasty (THA) is mechanical irritation or impingement of the iliopsoas tendon. The incidence is about 4%. If conservative therapy fails, an arthroscopic release of the iliopsoas tendon can be performed. The aim of the study was to assess the mid-term clinical outcome after arthroscopic release. We hypothesize that good results can be achieved by a minimally invasive endoscopic procedure.

METHODS

Using our in-house database, all patients who received an endoscopic release of the iliopsoas tendon due to mechanical irritation after THA were identified. Inclusion criteria were mechanical irritation of the iliopsoas tendon after cementless THA with minimal acetabular component prominence. Exclusion criteria were marked prominence of the acetabular component and groin pain after THA for any other reason. In these patients, the modified Harris Hip Score (mHHS), the pain level using the numerical analogue scale and the UCLA Activity Score were measured. The mean follow-up period was 7 ± 3.8 (2.6-11.7) years.

RESULTS

25 patients were identified in whom an arthroscopic release of the iliopsoas tendon had been performed since 2007. The data of 20 patients were available at follow-up. The gender ratio was 1:1, the average age at the time of arthroscopy was 59 ± 27.7 (52-78) years. The average interval between THA and arthroscopy was 6.3 ± 4.0 (1.7-15) years. The mHHS showed a significant improvement from preoperative 31.2 ± 9.8 (17.6-47.3) to 82.0 ± 9.8 (46.2-100) points (p = 0.001). The pain level on the NAS decreased significantly from 8.5 ± 1.2 (7-10) to 2.5 ± 1.8 (0-6) points (p = 0.001). The activity level based on the UCLA Activity Score raised from 4.0 ± 2.7 (0-7) to 6.5 ± 1.8 (3-9) (p = 0.09).

CONCLUSION

Mechanical irritation and impingement of the iliopsoas tendon is an important diagnosis to be considered in persistent groin pain after total hip arthroplasty. In failure of non-operative treatment, good clinical results can be achieved with arthroscopic release and the pain level can be significantly reduced.

LEVEL OF EVIDENCE

IV.

Iliopsoas Release: A Systematic Review of Clinical Efficacy and Associated Complications

OBJECTIVE

To perform a systematic review of the findings of iliopsoas release as it relates to resolution of snapping, improvement of groin pain, and associated complications.

DESIGN

Systematic review.

DATA SOURCES

Four electronic databases PubMed/MEDLINE, EMBASE, CINAHL, and Web of Science were searched, identifying all literature pertaining to surgical treatment of a snapping hip/coxa saltans, iliopsoas impingement, or iliopsoas tendinitis. A total of 818 studies were identified. Two reviewers independently screened the titles, abstracts, and full-text articles for eligibility.

ELIGIBILITY CRITERIA

All studies published in English that reported on iliopsoas release for snapping hip/coxa saltans, iliopsoas impingement, or iliopsoas tendinitis reporting outcomes or associated complications were eligible.

RESULTS

A total of 48 articles were included in this review. Three surgical indications were identified for iliopsoas release, internal snapping hip, labral tear secondary to iliopsoas impingement, and iliopsoas tendinopathy after total hip arthroplasty. Arthroscopic techniques seemed to be superior to open techniques with regards to reoccurrence of snapping (5.1% vs 21.7%) and groin pain relief (89.1% vs 85.6%) with fewer complications (4.2% vs 21.1%) overall.

CONCLUSIONS

Both open and arthroscopic iliopsoas releases have been shown to be successful treatment options regardless of the surgical indications identified in this review. Arthroscopic release demonstrated a decreased failure rate, fewer complications, and improved outcomes when compared with open procedures.

Modern Suture Anchor Techniques for Gluteus Medius Tear Repair With Concomitant Total Hip Arthroplasty Using the Direct Anterior and Posterior Approaches

Gluteus medius (GM) tears are currently a well-established source of pain and disability. However, their role in primary total hip arthroplasty (THA) in the setting of osteoarthritis (OA) has been underexamined in the literature. The purpose of this study was to report on short-term patient-reported outcome measurements (PROMs) for patients who underwent concomitant primary THA and GM repair. Data were prospectively collected from September 2011 and June 2017. Inclusion criteria were primary THA along with concomitant GM repair and complete follow-up for the Harris Hip Score, Forgotten Joint Score 12, Veterans RAND 12-item Health Survey both Physical and Mental, 12-item Short Form Survey both Physical and Mental (SF-12 P and SF-12 M), visual analog scale for pain, and patient satisfaction. Patients were excluded if they did not have follow-up. Thirty patients (30 hips) were included. Mean follow-up was 24.2±19.3 months. Twenty-nine (96.7%) patients were female. Mean age was 65.2±7.4 years. Mean body mass index was 31.1±5.9 kg/m². The posterior approach was used for 16 (53.3%) cases and the anterior approach for the remaining 14 (46.7%). Two (6.7%) patients had a less than 25% tear, 7 (23.3%) had a 25% to 50% tear, 14 (46.7%) had a greater than 50% tear, and 7 (23.3%) had a full-thickness tear. All PROMs except SF-12 M demonstrated significant improvement at latest follow-up. Patients who underwent THA with either the anterior or the posterior approach with concomitant GM repair using modern suture anchor techniques reported favorable PROMs at short-term follow-up. [Orthopedics. 2021;44(5):e653-e660.].

Endoscopic treatment of iliopsoas impingement after total hip arthroplasty: a minimum 2-year follow-up and comparison of tenotomy performed at the acetabular rim versus lesser trochanter

Iliopsoas impingement is an underdiagnosed cause of groin pain after total hip arthroplasty (THA), being responsible for 4.4% of cases. Non-surgical treatment may be effective in ∼50% of cases. Endoscopic surgery has gained popularity as an option for non-responsive patients because of its non-invasive characteristics, faster recovery and encouraging results. This study compares two different sites of endoscopic psoas tenotomy performed following THA: at the edge of the acetabulum (AR) versus at the lesser trochanter (LT). This is a retrospective review of prospectively collected data from a single-surgeon case series. Thirty-five iliopsoas tenotomy cases which had >24-month follow-up were identified. There were 21 tenotomies at the lesser trochanter. Demographic data, preop and postop pain, mHHS and NAHS scores, strength and patient satisfaction data were collected and analysed. Average age at the time of surgery was 62. Mean follow-up for the LT group was 49.11 months and 42.42 months for the AR group. Pain decreased significantly for both groups (P < 0.001). Both mHHS and NAHS showed superiority in the LT group, but this difference did not reach significance (P = 0.06). LT patients showed better strength with 71.42% of them having normal strength at latest follow-up, compared with 41.6% in the AR group. There were no complications in either group. Endoscopic tenotomy is a safe and reliable surgical option, giving significant pain relief and good functional outcomes. Tenotomy at the level of the lesser trochanter might be preferable since it shows better outcomes. Larger studies are necessary to achieve statistically significant results.

Outside-in arthroscopic psoas release for anterior iliopsoas impingement after primary total hip arthroplasty

PURPOSE

1 of the causes of groin pain after total hip arthroplasty (THA) is impingement of the iliopsoas tendon. The purpose of this study was to present our results with outside-in arthroscopic tenotomy for iliopsoas impingement after THA.

METHODS

We retrospectively reviewed 12 patients treated between 2009 and 2016 with a minimum follow-up of 2 years. Anterior acetabular component prominence was measured on a true lateral hip radiograph. A transcapsular tenotomy was performed near the edge of the acetabular component through an outside-in arthroscopic approach. The primary clinical outcomes evaluated were groin pain, assessed with a visual analogue scale (VAS), and the Harris Hip Score (HHS). Secondary outcomes included strength of hip flexion, measured with the Medical Research Council (MRC) scale.

RESULTS

All patients had groin pain improvement, though one patient continued to have moderate pain. The mean VAS score was significantly lower postoperatively (1.08) than preoperatively (6.2) (p < 0.001). The mean HHS improved from 58.8 (range, 37-76) to 86.1 (range, 59-98) (p = 0.001). The average postoperative MRC Scale was 4.58. The mean anterior prominence was 7.25 mm (range 3-12 mm). In patients with <10 mm of component prominence, tenotomy provided groin pain resolution in all cases (n = 8). In patients with ⩾10 mm of prominence, symptoms resolved in 3 out of 4 cases.

CONCLUSIONS

Outside-in arthroscopic iliopsoas release provided a high rate of success with no complications in this study, even in patients with moderate acetabular component prominence.

Endoscopic Tenotomy for Iliopsoas Tendinopathy Following Total Hip Arthroplasty Can Relieve Pain Regardless of Acetabular Cup Overhang or Anteversion

PURPOSE

To report outcomes of endoscopic iliopsoas tenotomy (EIT) in patients with iliopsoas tendinopathy following total hip arthroplasty (THA) and determine whether improvements in clinical scores are associated with acetabular cup anteversion measured on plain radiographs or overhang measured using established and alternative computed tomography (CT)-based methods.

METHODS

We evaluated patients who underwent EIT for iliopsoas tendinopathy after THA (2014-2017), performed between the lesser trochanter and psoas valley. Indications were groin pain during active hip flexion, exclusion of other complications, and no pain relief after 6 months of conservative treatment. Pretenotomy inclination and anteversion were measured on radiographs; sagittal and axial overhang were measured on CT scans on slices passing through: (Method 1) prosthetic head center and (Method 2) anterior margin of acetabular cup. Modified Harris hip score (mHHS), Oxford Hip Score (OHS), and level of groin pain were recorded at 12 or more months. Wilcoxon signed-rank tests were used to compare pre- and post-tenotomy scores, and intraclass correlation coefficients (ICCs) to assess intermethod agreement.

RESULTS

The cohort comprised 16 men (17 hips) and 32 women (33 hips), aged 60.8 ± 10.5 years at EIT. For the 30 (60%) hips that had pretenotomy CT scans, axial and sagittal overhang were, respectively, 3.4 ± 3.7 mm and 4.6 ± 4.6 mm, using Method 1, compared with 3.9 ± 3.9 mm and 6.9 ± 5.0 mm using Method 2. Intermethod agreement was good for axial (ICC, 0.67; P < .001) and sagittal (ICC, 0.68; P < .001) overhang. At a minimum 1 year after EIT, 3 hips had cup and stem revision and 1 hip had isolated cup revision, leaving 46 hips for clinical assessment. No complications were noted. mHHS improved by 26 ± 19 (P < .001) and OHS improved by 20 ± 11 (P < .001). Twenty-six hips (57%) achieved the patient acceptable symptom state for mHHS, whereas 42 hips (91%) achieved the patient acceptable symptom state for OHS. Post-tenotomy groin pain was slight in 15%, mild in 17%, and moderate in 11%. Regression analyses revealed no associations between clinical scores and overhang/anteversion.

CONCLUSIONS

For patients with iliopsoas tendinopathy following THA, endoscopic iliopsoas tenotomy granted clinically important improvements of mHHS in 76% and OHS in 89%, despite moderate residual groin pain in 11%. Improvements in clinical scores did not seem to be associated with the extent of cup overhang or anteversion in the cases for which adequate preoperative imaging was available.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Iliopsoas Impingement After Direct Anterior Approach Total Hip Arthroplasty: Epidemiology, Risk Factors, and Treatment Options

BACKGROUND

The objective of this study is to evaluate the incidence, natural history, response to treatment, and risk factors for anterior iliopsoas impingement (AIPI) after direct anterior approach (DAA) total hip arthroplasty (THA).

METHODS

Between January 1, 2009 and January 4, 2014, 600 patients (655 hips) who underwent primary DAA THA were retrospectively reviewed. AIPI incidence was calculated. Natural history and response to a stepwise treatment approach was assessed. Radiographic anterior acetabular component overhang was measured. Asymptomatic controls were used to identify risk factors for the development of AIPI.

RESULTS

In total, 518 patients (559 hips) met the inclusion criteria. The incidence of AIPI was 32/559 (5.7%). Symptom resolution occurred in 22/32 (68.8%) patients at final follow-up. Nonoperative management was successful in 15/32 (46.9%) patients. Operative intervention resulted in symptom resolution in 5/8 (62.5%) patients. On univariate analysis, female gender (odds ratio [OR] 2.79), acetabular component to native femoral head diameter ratio above 1.1 (OR 3.85), and any measurable overhang (OR 7.07) significantly raised the risk of AIPI, while increasing native femoral head diameter was protective for AIPI (OR 0.83).

CONCLUSION

AIPI is a cause of groin pain after DAA THA, which often improves with conservative measures. Significant predisposing factors for AIPI include female gender, small native femoral head diameter, increased acetabular component to femoral head diameter ratio, and most notably, any measurable acetabular component overhang.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The Limited Reliability of Physical Examination and Imaging for Diagnosis of Iliopsoas Tendinitis

PURPOSE

To determine if any association exists between physical examination, imaging findings [ultrasound (US) and magnetic resonance imaging (MRI)], and iliopsoas tendinitis (IPT) to characterize the reliability of these diagnostic modalities.

METHODS

Patients who had undergone US-guided iliopsoas tendon sheath injection (of lidocaine and a corticosteroid agent) as well as MRI performed within 1 year of injection from 2014 to 2019 were retrospectively reviewed. Demographic data, response to physical exam maneuvers, and response to injection were queried from patient records. US and MRI were reviewed by 2 independent musculoskeletal-trained radiologists. Response to injection was considered positive if the patient improved by >2 points on a 0- to 10-point VAS score. Chi-squared and Fisher exact testing were used to assess for any associations. Sensitivities, specificities, positive predictive values, and negative predictive values were calculated.

RESULTS

Sixty-three patients, age 52.3 ± 17.3 years (mean ± standard deviation), body mass index 27.4 ± 4.3 kg/m², and follow-up 33.6 ± 20.6 months, met inclusion criteria. No physical exam maneuvers, sonographic features, or MRI findings were significantly associated with response to iliopsoas tendon injection (P > .05). Groin pain had a sensitivity of 100% but a specificity of 7%. Snapping hip had a specificity of 82% but a sensitivity of 24%. Pain with resisted straight leg raise (SLR) (sensitivity 62%, specificity 25%) and weakness with resisted SLR (sensitivity 15%, specificity 71%) both were nonreliable. Sonographic bursal distension and tendinosis had low sensitivities (67% and 63%, respectively) and specificities (35% and 32%). Bursal distension on MRI had sensitivity and specificity of 64% and 45%, respectively. Tendon thickening had sensitivity and specificity of 55% and 60%, respectively, and heterogeneity had sensitivity and specificity of 52% and 65%.

CONCLUSION

Neither physical examination nor US or MRI findings were associated with a positive response to peritendinous iliopsoas corticosteroid injections in patients with suspected IPT.

LEVEL OF EVIDENCE

III, retrospective comparative trial limited by lack of a reference standard for iliopsoas tendonitis diagnosis.

Iliopsoas pathology after total hip arthroplasty: a young person's complication

AIMS

Iliopsoas pathology is a relatively uncommon cause of pain following total hip arthroplasty (THA), typically presenting with symptoms of groin pain on active flexion and/or extension of the hip. A variety of conservative and surgical treatment options have been reported. In this retrospective cohort study, we report the incidence of iliopsoas pathology and treatment outcomes.

METHODS

A retrospective review of 1,000 patients who underwent THA over a five-year period was conducted, to determine the incidence of patients diagnosed with iliopsoas pathology. Outcome following non-surgical and surgical management was assessed.

RESULTS

In all, 24 patients were diagnosed as having developed symptomatic iliopsoas pathology giving an incidence of 2.4%. While the mean age for receiving a THA was 65 years, the mean age for developing iliopsoas pathology was 54 years (28 to 67). Younger patients and those receiving THA for conditions other than primary osteoarthritis were at a higher risk of developing this complication. Ultrasound-guided steroid injection/physiotherapy resulted in complete resolution of symptoms in 61% of cases, partial resolution in 13%, and no benefit in 26%. Eight out of 24 patients (who initially responded to injection) subsequently underwent surgical intervention including tenotomy (n = 7) and revision of the acetabular component (n = 1).

CONCLUSION

This is the largest case series to estimate the incidence of iliopsoas pathology to date. There is a higher incidence of this condition in younger patients, possibly due to the differing surgical indications. Arthoplasty for Perthes' disease or developmental dysplasia of the hip (DDH) often results in leg length and horizontal offset being increased. This, in turn, may increase tension on the iliopsoas tendon, possibly resulting in a higher risk of psoas irritation. Image-guided steroid injection is a low-risk, relatively effective treatment. In refractory cases, tendon release may be considered. Patients should be counselled of the risk of persisting groin pain when undergoing THA. Cite this article: Bone Joint J 2021;103-B(2):305-308.

Surgical Management of Iliopsoas Impingement With Combined Acetabular Revision and Partial Psoas Tenotomy

Background

Persistent groin pain after total hip arthroplasty (THA) can result from iliopsoas impingement (IPI) on the acetabular rim. Controversy exists over the risks and benefits of tenotomy versus revision as a surgical solution. We report our limited experience with combined acetabular revision and partial iliopsoas tenotomy when other conservative treatments have failed.

Methodology

A total of eight patients revised for IPI by a single surgeon at a single institution were retrospectively reviewed after a minimum one-year follow-up. Preoperatively, all patients had prolonged groin pain for a mean of two years (range: 1-4 years) and had failed conservative treatment for at least six months. All patients underwent acetabular revision through a direct anterior approach (DAA) with partial psoas tendon release. No stems were revised. Dislocations, complications, and clinical outcomes are reported in this study.

Results

Of the eight patients, seven had a positive diagnostic challenge with an image-guided injection. All revised cups showed radiographic evidence of IPI with relative acetabular retroversion by either a cross-table lateral film or computed tomography scan. Preoperatively, the mean cup anteversion was 4 degrees (range: 0-9 degrees). Postoperatively, the mean cup anteversion was 19 degrees (range: 16-21 degrees). All cups were within the so-called safe zone. To avoid overstuffing, the mean cup size remained unchanged. There were no major postoperative complications. At a mean time to follow-up of 3.3 years, the mean Hip disability and Osteoarthritis Outcome Score for Joint Replacement was 75 points (range: 32-100 points).

Conclusion

IPI may be effectively managed with combined acetabular revision and tenotomy. The challenges of implant placement and positioning may be aided with intraoperative imaging through a DAA THA.

Repair of Symptomatic Partial Gluteus Medius Tear During Total Hip Arthroplasty Through the Direct Anterior Approach

Gluteus medius (GM) tears are a well-established source of pain and disability. Considering previous studies, which have reported rates of incidental GM tears in 20% of patients undergoing primary total hip arthroplasty (THA) and a 3-fold greater rate in elderly female patients, additional focus should be placed on identifying treatment options. The direct anterior approach (DAA) for primary THA has gained popularity within the past few years. However, there has been a paucity in the literature on how to address symptomatic and partial GM tears through this approach. The purpose of this Technical Note is to describe a method to repair partial GM tears during primary THA using the DAA.

Arthroscopic tendon release for iliopsoas impingement after primary total hip arthroplasty: a retrospective, consecutive series

INTRODUCTION

Aim of this study was to describe the clinical outcomes of 16 patients with iliopsoas (IP) impingement after primary total hip arthroplasty (THA), treated with an arthroscopic tendon release.

METHODS

16 patients (11 females/5 males), with a mean age of 57.8 ± 11.1 years (age at THA: 54.4 ± 11 years) and a diagnosis of IP impingement after primary THA, were treated with the Wettstein tenotomy. Preoperatively, every patient underwent a diagnostic ultrasonography guided peritendinous injection and a computed tomography (CT) scan. Every patient was clinically evaluated using WOMAC score. Subjective pain relief and active hip flexion strength were measured.

RESULTS

No complications related to arthroscopy were detected. Every cup was prominent with a mean axial overhang of 13 ± 4.8 mm (range 5-20 mm). At a mean follow-up of 27 ± 20.1 months (range 6-48 months), the WOMAC score was 83.7 ± 10.1 points. 13 patients out of 16 (81.3%) had a complete pain relief. 14 patients out of 16 (88%) regained full active hip flexion strength at the final follow-up. 1 patient was scheduled for cup revision after 6 months, due to persistent symptomatology. No demographic data or CT measurements about cup position statistically influenced the outcome.

CONCLUSIONS

When preceded by an appropriate diagnosis, arthroscopic tenotomy proved safe and effective for IP impingement, regardless the magnitude of cup protrusion.

Low Back Pain Caused by Iliopsoas Tendinopathy Treated with Ultrasound-Guided Local Injection of Anesthetic and Steroid: A Retrospective Study

Background

Low back pain is a prevalent symptom that occurs in all age of people, whereas the pathogenesis is unknown. Iliopsoas tendinopathy is an increasingly recognized hip disorder that may contribute to low back pain. Our purpose is to evaluate the effect of ultrasound-guided local injection of anesthetic and steroid into the trigger point of iliopsoas tendon in treating low back pain caused by iliopsoas tendinopathy.

Materials and Methods

This retrospective study reviewed 45 patients diagnosed with iliopsoas tendinopathy treated by B-ultrasound guided injection of 2 mL 2% lidocaine and 1 mL (5 mg) triamcinolone acetonide into the trigger point of iliopsoas tendon from March 2016 to June 2016. Medical records were collected to analyze the clinical presentation. Numerical Rating Scale (NRS) measuring low back pain and Harris Hip score (HHS) measuring hip pain and function were administered to determine patient outcomes. Telephone follow-up was conducted, and the mean follow-up was 11 months.

Results

We observed that most patients with iliopsoas tendinopathy also complain about chronic low back pain except for groin pain. After injection of anesthetic and corticosteroid into the iliopsoas tendon, the NRS of patients with low back pain fell from 7.68±1.31 to 2.58±1.16 immediately after the injection and 0.75±0.73 at follow-up. The HHS improved from 43.02±16.81 to 98.15±2.56 at follow-up. Statistically significant difference (P<0.001) was observed. All patients returned to their original level of function, and only five patients presented with mild low back pain at the follow-up.

Conclusion

Low back pain is a prevalent presentation for iliopsoas tendinopathy. Diagnosis of iliopsoas tendinopathy should be considered in patients with low back pain with tenderness over the iliopsoas tendon. Ultrasound-guided local injection of anesthetic and steroid lead to satisfactory effect in relieving low back and groin pain and improving joint function.

Arthroscopic treatment of iliopsoas tendinitis after total hip arthroplasty with acetabular cup malposition: Two case reports

BACKGROUND

Optimal treatment for iliopsoas tendinitis after total hip arthroplasty (THA) with cup malposition, iliopsoas release alone or with cup revision, is controversial, particularly in young, active patients. Moreover, arthroscopic iliopsoas tendon (IPT) release in these patients has been rarely described, and midterm effects of this procedure on THA longevity and groin pain recurrence remain unclear. We performed arthroscopic IPT release after THA and report midterm outcomes in two young patients with acetabular cup malposition.

CASE SUMMARY

In the two patients, groin pain started early after THA. Physical examination revealed nonspecific findings, and laboratory tests showed no evidence of infection. Radiography and computed tomography showed reduced acetabular component anteversion angle and anterior cup prominence of more than 16 mm. For therapeutic diagnosis, ultrasonography-guided lidocaine with steroid was injected into the IPT sheath. In both patients, groin pain improved initially but worsened after a few months. Therefore, the patients underwent arthroscopic IPT release under spinal anesthesia. Arthroscopy revealed synovitis with fibrous tissues around the IPT and various lesions related to the implants after THA. IPT tenotomy and debridement with biopsy were performed; histopathologic studies showed chronic inflammation with synovial hyperplasia. Both patients were encouraged to start walking immediately after surgery, and they returned to complete daily function early after surgery. They experienced no recurrence of groin pain or any implant-related problems 5 years postoperatively.

CONCLUSION

Arthroscopic IPT release for cup malposition produced excellent midterm outcomes without recurrence of groin pain and implant-related problems.

Outcome of Ceramic-on-Ceramic Total Hip Arthroplasty with 4th Generation 36 mm Head Compared to that with 3rd Generation 28 mm Head by Propensity Score Matching

BACKGROUND

With the development of 4th generation ceramic bearing, the large ceramic head is available for ceramic-on-ceramic total hip arthroplasty (THA). This retrospective study aimed to compare the outcomes of ceramic-on-ceramic THA with 4th generation 36 mm head to those with 3rd generation 28 mm head using propensity score matching.

METHODS

We retrospectively reviewed the results of 133 ceramic-on-ceramic THAs with 4th generation 36 mm ceramic head in 129 patients and 133 ceramic-on-ceramic THAs identified from 405 ceramic-on-ceramic THAs with 3rd generation 28 mm head by propensity score matching. There were 83 males and 50 females in both groups with a mean age of 55 years. There was no significant difference in other demographic features except for follow-up period (4.2 years in the 36 mm group and 6.4 years in the 28 mm group, p < 0.001). Clinical and radiological results and occurrence of complication were compared between the two groups.

RESULTS

Harris Hip Score was increased significantly from 46.4 to 92.1 in the 36 mm group and from 46.7 to 93.6 in the 28 mm group. No loosening or osteolysis was observed in the 36 mm group. However, one hip showed radiologic sign of loosening in the 28 mm group. As for complication, postoperative dislocation was more frequent in the 28 mm group (6 in the 28 mm group vs. 0 in the 36 mm group, p = 0.03). Otherwise, there was no significant difference in other results including inguinal pain, squeaking or ceramic fracture.

CONCLUSION

Ceramic-on-ceramic THA with 4th generation 36 mm head significantly reduced postoperative dislocation rate without increasing the rate of inguinal pain, squeaking, or ceramic fracture compared to that with 3rd generation 28 mm head.

Risk factors for iliopsoas impingement after total hip arthroplasty using a collared femoral prosthesis

Background

The relationship between collar design of a femoral component and iliopsoas impingement (IPI) after total hip arthroplasty (THA) is still underrecognized. The purpose of our study was to determine the possible risk factors for IPI related to the femoral component, when using a collared femoral prosthesis.

Methods

A total of 196 consecutive THA patients (206 hips) using a collared femoral prosthesis were reviewed retrospectively after exclusion of the factors related to acetabular component and femoral head. The patients were divided into +IPI and −IPI group according to the presence of IPI. Radiological evaluations were performed including femoral morphology, stem positioning, and collar protrusion length (CPL). Multivariate regression analysis was performed to assess the risk factors for IPI.

Results

At a minimum follow-up of 1 year, IPI was observed in 15 hips (7.3%). Dorr type C proximal femur was found in nine hips (60%) in the +IPI group and in 28 hips in the −IPI group (14.7%, p < 0.001). The mean stem anteversion in the +IPI group was significantly greater than that in the −IPI group (19.1° vs. 15.2°, p < 0.001), as well as the mean CPL (2.6 mm vs. − 0.5 mm, p < 0.001). The increased stem anteversion (OR = 1.745, p = 0.001) and CPL (OR = 13.889, p = 0.001) were potential risk factors for IPI.

Conclusions

The incidence of IPI after THA is higher than expected when using a collared femoral prosthesis. Among the factors related to collared femoral prosthesis, excessively increased stem anteversion and prominent collar protrusion are independent predictors for IPI. In addition, high risk of IPI should be carefully considered in Dorr type C bone, despite that femoral morphology is not a predictive factor.

Level of evidence

Level IV, clinical cohort study

Achievement of optimal implant alignment using taper wedge stems with cup-first THA through the MIS antero-lateral approach

PURPOSE

Combined anteversion (CA) technique (stem-first procedure) has become generally accepted as an ideal means to achieve optimal CA value in THA. However, we hypothesized that CA technique for patients with various native femoral anteversions could pose a risk of anterior or posterior cup protrusion. In the present study, we examined whether it is possible to use the taper wedge stem to change the stem version to achieve optimal CA while avoiding cup protrusions with the cup-first procedure through minimally invasive (MIS) antero-lateral approach.

METHODS

Eighty-one patients underwent cup-first THA with a taper wedge stem. The acetabular cup was placed following the preoperative planning of the cup alignment to avoid anterior cup protrusions using CT-based navigation. Following the CA theory, anteversion of the taper wedge stem was changed to the target anteversion from the patient's native femoral anteversion. The native femoral anteversion, the change in version angle of the stem, postoperative CA and the length of anterior cup protrusions were evaluated in postoperative CT measurements.

RESULTS

The native femoral anteversion averaged 25.7° ± 8.9° (range 8°-45°). Cases with increased and decreased stem anteversion were observed in 42 hips (51.8%) and 33 hips (40.7%), respectively. The amount of increased and decreased version angles averaged 7.7° ± 4.8° (range 2°-21°) and 7.8° ± 5.1° (range 2°-20°), respectively. Postoperative CA values averaged 36.7° ± 3.4° (range 29.4°-44.2°) and anterior cup protrusion length averaged 2.0 mm ± 2.6 mm (0 ~ 8.8 mm) in axial view and 0.4 mm ± 1.0 mm (0 ~ 3.6 mm) in sagittal view. Anterior cup protrusion of more than 10 mm was not observed in any hips.

CONCLUSION

This procedure can be considered as an option to achieve optimal CA anteversion while avoiding anterior cup protrusion in THA.

Physical therapy management of a patient with persistent groin pain after total hip arthroplasty and iliopsoas tenotomy: a case report

BACKGROUND

Hip impingement syndrome can occur after total hip arthroplasty (THA). Nonoperative treatment is inconsistently recommended, and surgical options include iliopsoas tenotomy. The current case report describes the unique case of a patient with persistent groin pain after THA and iliopsoas tenotomy.

CASE DESCRIPTION

The 72-year-old male had persistent groin pain after right THA and an unsuccessful iliopsoas tenotomy. He had pain and limited right hip range of motion during active and passive hip flexion, abduction, and external rotation. Treatment consisted of high-grade joint mobilization to improve the range of motion of the right hip and an exercise program.

OUTCOMES

The patient was treated for six visits over 3 weeks. Clinically important improvements were noted in pain, function, and perceived level of improvement. Pain during hip flexion improved on the Numeric Pain Rating Scale, and function improved on the Lower Extremity Functional Scale. Improvements in the range of motion and strength were also observed. At 6-month follow-up, he reported maintenance of improvements.

DISCUSSION

Joint mobilization and exercise were effective for improving range of motion, groin pain, and function in a patient with a 4-year history of persistent groin pain after THA and subsequent iliopsoas tenotomy.

Improved accuracy of CT based measurements for anterior prominence of acetabular prosthesis using a novel protocol based on anatomical landmarks

BACKGROUND

Anterior hip pain after total hip replacement (THR) can be caused by iliopsoas impingement (IPI). Validation of CT measured cup version is well published; however quantification of the anterior cup prominence has not been validated. Therefore, we did an in vitro study aiming to: (1) assess the accuracy of the current method of measuring the prominence of the acetabular component using a dry bone model; (2) develop a CT protocol based on bony anatomical landmarks that improves the accuracy of these measurements.

HYPOTHESIS

We hypothesise that utilising reproducible anatomical landmarks on the acetabulum will improve the accuracy of measurement of anterior prominence at the psoas valley.

METHODS

A dry bone pelvic model was implanted with bilateral acetabular cups. The cup was manipulated into ten different combinations of inclination and version, and anterior prominence directly measured in relation to the acetabular rim. A CT scan was performed for each position. Anterior prominence was then measured by two radiologists, first using standard methods (axial slice at level of centre of femoral head) and then again using a novel protocol (based on the position of the psoas valley in relation to the inferior medial acetabular notch).

RESULTS

Mean errors between direct measurement of anterior prominence and radiologist reported measurements using standard protocol were 6.94mm±5.24 (SD) (95%Confidence Interval: 3.25-4.27) and 5.14mm±3.07 (95%CI: 1.9-2.5) with a tendency towards overestimation of prominence. Using an anatomical landmark based protocol; mean error was reduced to 3.0mm±1.9 (95%CI: 1.16-1.53) and 4.3mm±4.3 (95%CI: 2.67-351) on the first attempt, and to 1.7mm±1.9 (95%CI: 1.15-1.52) and 2.1mm±1.4 (95%CI: 0.87-1.15) on the second attempt. Concordance correlation improved from 0.43 (95% CI: 0.19-0.68) and 0.59 (95% CI: 0.44-0.79) using the standard protocol, to 0.88 (95%CI: 0.61-0.91) and 0.9 (95%CI: 0.56-0.92) using the novel protocol.

CONCLUSIONS

There is a difference in mean error and reliability between radiologically measured values for anterior prominence and values measured directly with present methods. The use of our novel protocol based on bony acetabular landmarks, significantly improves the accuracy of measurement. This protocol may improve reproducibility and the accuracy of this measurement and aid in the decision between tenotomy or revision of the acetabular component.

LEVEL OF EVIDENCE

III, in vitro study comparing diagnostic tools.

New combined anteversion technique in hybrid THA: cup-first procedure with CT-based navigation

PURPOSE

Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA value in total hip arthroplasty (THA). However, cup anteversion is strongly influenced by the native femoral anteversion. Accordingly, anterior protrusion of the cup in the acetabulum might occur. The purpose of the present study is to investigate the achievement of the optimal CA while avoiding anterior cup protrusion and examine the significance of our new CA technique with cup-first procedure in hybrid THA.

METHODS

Seventy-nine hybrid THAs with the cup-first procedure used a CT-based navigation system for cup positioning. In the preoperative planning, cup anteversion was aimed at approximately 20°. However, in actuality, sufficient cup coverage in the original acetabulum based on individual anatomy is given priority over cup placement based on CT-based planning to ensure adequate cup coverage. The target stem anteversion was determined following Widmer's mathematical formula (37.3 = femoral stem anteversion × 0.7 + cup anteversion). Cemented stem was inserted according to the target stem anteversion angle.

RESULTS

Regarding the assessment of overall alignment, the calculated Widmer's CA values during surgery and postoperative CT evaluation were 34.1° ± 6.0° (range 20.7°-51.2°) and 35.1° ± 6.7° (range 21.6°-50.7°). There were 72 hips (91.1%) within 25°-50° of CA. Cup protrusion length averaged 2.0 mm ± 2.6 mm (0-8.8 mm) in the axial view and 0.4 mm ± 1.0 mm (0-3.6 mm) in the sagittal view. Cup protrusion length of more than 5 mm was indicated in 10 hips, and no hips observed more than 10 mm.

CONCLUSION

Our new CA technique (cup-first procedure) with hybrid THA was able to achieve optimal CA value while avoiding anterior cup protrusion.

The Accuracy of the Computed Tomography-Based Navigation System in Total Hip Arthroplasty Is Comparable With Crowe Type IV and Crowe Type I Dysplasia: A Case-Control Study

BACKGROUND

Clinical outcomes of total hip arthroplasty (THA) for Crowe type IV are poorer than for Crowe type I, because it is more difficult to accurately position the acetabular components. This study aimed to examine the accuracy of the computed tomography (CT)-based navigation system for acetabular component positioning in primary THA for Crowe type IV.

METHODS

From 2006 to 2018, 29 patients who underwent 34 primary THAs for Crowe type IV were enrolled in the "Type IV" group and 32 patients who underwent 34 THAs for Crowe type I were enrolled in the "Type I" group, formed by matching patients in the Type IV group on age, gender, body mass index, and surgical approach. We investigated (1) the accuracy of the cup size between that at preoperative planning and that actually implanted and (2) the mean deviation of the cup angle and 3-dimensional position of acetabular components between preoperative plan and postoperative records.

RESULTS

The accuracy of the cup size was 79.4% and 94.1% in the Type IV and Type I groups, respectively, without a statistically significant change detected (P = .075). The mean deviations of the cup angle and 3-dimensional position were comparable in both groups.

CONCLUSION

Using the CT-based navigation system, it was possible to accurately implant the acetabular component for Crowe type IV, and the accuracy was comparable to that for Crowe type I. The CT-based navigation system is a useful intraoperative tool to accurately implant the acetabular component, especially with severe pelvic deformities such as Crowe type IV.

What is the Diagnostic Accuracy of MRI for Component Loosening in THA?

BACKGROUND

Implant loosening is a common cause of reoperation after THA. Plain radiographs have been the default modality to evaluate loosening, although radiographs provide a relatively insensitive assessment of integration; cross-sectional modalities may provide a more detailed evaluation but traditionally have suffered from metal-related artifacts. We sought to determine whether MRI is capable of reliably detecting operatively confirmed component loosening in patients after hip arthroplasty.

QUESTIONS/PURPOSES

(1) Is assessing implant integration using MRI (with multiacquisition variable resonance image combination, [MAVRIC]) repeatable between readers? (2) What is the sensitivity and specificity of MRI with MAVRIC to evaluate component loosening, using intraoperative assessment as a gold standard? (3) How does the sensitivity and specificity of MRI with MAVRIC for surgically confirmed component loosening compare with those of radiographs?

METHODS

Between 2012 and 2017, 2582 THAs underwent revision at one institution. Of those, 219 had a preoperative MRI with MAVRIC. During that period, the most common indication for obtaining an MRI was evaluation of potential adverse local tissue reaction. The surgeons' decision to proceed with revision was based on their overall assessment of clinical, imaging, and laboratory findings, with MRI findings cited as contributing to the decision to revise commonly occurring in the setting of recalled implants. Of the THAs that underwent MRI, 212 were included in this study, while seven were excluded due to equivocal operative notes (5) and excessively poor quality MRI (2). MRI was performed at 1.5T using a standardized arthroplasty imaging protocol, including MARS (metal artifact reduction sequencing) and MAVRIC techniques. Two independent musculoskeletal fellowship-trained readers (one with 26 and one with 5 years of experience) blinded to operative findings scored a subset of 57 hips for implant integration based on Gruen zone and component loosening (defined as complete circumferential loss of integration around a component) to evaluate interobserver reliability. A third investigator blinded to imaging findings reviewed operative notes for details on the surgeon's assessment of intraoperative loosening.

RESULTS

Gwet's agreement coefficients (AC) were used to describe interobserver agreement; these are similar to Cohen's kappa but are more resistant to certain paradoxes, such as unexpectedly low values in the setting of very high or low trait prevalence, or good agreement between readers on marginal counts. Almost perfect interobserver agreement (AC2 = 0.81-1.0) was demonstrated for all acetabular zones and all femoral Gruen zones on MRI, while perfect (AC1 = 1.0) agreement was demonstrated for the overall assessment of acetabular component loosening and near perfect agreement was shown for the assessment of femoral component loosening (AC1 = 0.98). MRI demonstrated a sensitivity and specificity of 83% (95% CI, 65-96) and 98% (95% CI, 97-100), respectively, for acetabular component loosening and 75% (95% CI, 55-94) and 100% (95% CI, 100-100), respectively, for femoral component loosening. Radiographs demonstrated a sensitivity and specificity of 26% (95% CI, 12-47) and 100% (95% CI, 96-100), respectively, for acetabular component loosening and 20% (95% CI, 9-47) and 100% (95% CI, 100-100), respectively, for femoral component loosening.

CONCLUSION

MRI may provide a repeatable assessment of implant integration and demonstrated greater sensitivity than radiographs for surgically confirmed implant loosening in patients undergoing revision THA at a single institution. Additional multi-institutional studies may provide more insight into the generalizability of these findings.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Outcomes of Nonoperative Management, Iliopsoas Tenotomy, and Revision Arthroplasty for Iliopsoas Impingement after Total Hip Arthroplasty: A Systematic Review

BACKGROUND

Nonoperative and operative management of iliopsoas impingement (IPI) is commonly performed following total hip arthroplasty (THA). The purpose of this systematic review is to compare patient-reported outcomes (PROs) following conservative treatment, iliopsoas (IP) tenotomy, and revision arthroplasty in patients presenting with IPI after THA.

METHODS

The PubMed and Embase databases were searched for articles regarding IPI following THA. Studies were included if (1) IPI after THA was treated with conservative management, an IP tenotomy, or acetabular component revision and (2) included PROs.

RESULTS

Eleven articles were selected for review and there were 280 hips treated for IPI following THA. Harris Hip Scores reported for the conservative group, the IP tenotomy group, and the cup revision group were 59.0 preoperatively to 77.8, 58.0 preoperatively to 85.4, and 58.1 preoperatively to 82.4 at latest follow-up, respectively. The IP tenotomy cohort also demonstrated superior postoperative functional outcomes using the Western Ontario and McMaster Universities Index, Medical Research Council score, Oxford Hip Score, and Merle d'Aubigné-Postel Pain Score. Patients who had a revision exhibited higher Oxford Hip Scores, higher Medical Research Council scores, and lower Visual Analog Scale Pain scores postoperatively.

CONCLUSION

Management of IPI following THA includes nonoperative measures, IP tenotomy, or acetabular component revision. Patients have been shown to experience favorable PROs at latest follow-up, with an apparent advantage for surgical treatment. Compared to revision arthroplasty, IP tenotomy resulted in a lower overall rate of complications with less severe complication types. Therefore, IP tenotomy should be considered as a second line of treatment for patients who failed conservative measures. Revision arthroplasty should be reserved for recalcitrant cases.

LEVEL OF EVIDENCE

IV.

Evaluation of Endoscopic Iliopsoas Tenotomy for Treatment of Iliopsoas Impingement After Total Hip Arthroplasty

BACKGROUND

Iliopsoas impingement after total hip arthroplasty (THA) occurs in up to 4.3% of patients resulting in functional groin pain. Operative treatment historically has included open iliopsoas tenotomy or acetabulum revision. We present a large single surgeon series of patients treated with endoscopic iliopsoas tenotomy for iliopsoas impingement after THA to evaluate the effectiveness and risks.

METHODS

A consecutive series of 60 patients with iliopsoas impingement after THA treated with endoscopic iliopsoas tenotomy was retrospectively evaluated. Outcomes assessed were resolution of pain, change in Hip Outcome Score (HOS), and complications. Radiographs were reviewed by a musculoskeletal radiologist to evaluate component positioning and to compare with a control cohort.

RESULTS

At last follow-up (mean 5.5 months), 93.3% of patients had resolution of pain. The HOS activities of daily living (ADL) subscale mean was 57.5 (range 10.9-89.3, standard deviation [SD] 18.8) preoperatively and 71.6 (range 14.1-100, SD 26.1) postoperatively (P = .005). The HOS sports subscale mean was 37.3 (range 0-83.3, SD 24.0) preoperatively and 58.1 (range 0-100, SD 33.2) postoperatively (P = .002). One complication was reported, a postoperative hematoma managed conservatively. Body mass index and increased offset were associated with iliopsoas symptoms after THA in this series.

CONCLUSION

Endoscopic iliopsoas tenotomy after THA had a 93.3% resolution of pain, clinically important improvements in HOS, and low rate of complications. Endoscopic tenotomy should be considered as a treatment option in patients with iliopsoas impingement after THA.

Arthroscopic Diagnosis and Treatment of Chronic Hip Pain After Total Hip Arthroplasty and the Role of Anterior Capsule Disruption in Iliopsoas Tendinopathy

Background:

The use of hip arthroscopic surgery in patients suffering from chronic hip pain after total hip arthroplasty (THA) has a limited presence in the literature, with most studies having limited follow-up.

Purpose:

The first goal of this study was to evaluate hip arthroscopic surgery in the diagnosis and management of patients with chronic hip pain after THA. The second goal was to describe a new cause of iliopsoas tendinopathy (IPT) involving disruption of the anterior capsule.

Study Design:

Case series; Level of evidence, 4.

Methods:

We conducted a retrospective analysis with prospectively collected clinical outcomes of patients after THA who underwent hip arthroscopic surgery for chronic hip pain without an identifiable cause. The patients were at least 18 years old and had a minimum follow-up of 24 months.

Results:

The retrospective analysis found that hip arthroscopic surgery led to new diagnostic information in 8 patients (80%). Of the 10 patients diagnosed with IPT, 4 (40%) lacked an anatomic cause; however, these patients had a history of difficult exposure of the anterior capsule and/or a lack of capsular repair during index THA. The mean modified Harris Hip Score (mHHS) was 71.9 ± 15.6, and the mean 6-month postoperative visual analog scale (VAS) pain score was 0.8 ± 2.2, which was significantly lower than preoperatively (P = .0055). There was also significantly improved forward flexion range of motion (P = .0183) and straight leg raise (SLR) strength test results (P = .0263). Hip arthroscopic surgery resulted in 8 patients (80%) continuing to be pain-free at a mean follow-up of 6.8 ± 1.4 years, while 2 patients (20%) progressed to revision arthroplasty. There were no major or minor complications.

Conclusion:

Hip arthroscopic surgery was found to have an important role in the diagnostic and therapeutic management of patients with chronic hip pain after THA, with good clinical outcomes at a mean follow-up of 6.8 years and no complications. We believe that disruption of the anterosuperior acetabular capsule, including the reflected head of the rectus femoris, can allow the iliopsoas tendon to move intra-articularly and precipitate IPT. This disruption may be appreciated on the SLR strength test. Although this study presents a small sample size that cannot substantiate a cause-effect relationship, orthopaedic surgeons performing THA should consider minimizing disruption and/or ensuring repair of the anterior capsule to decrease this potential cause of IPT.

Iliopsoas tendonitis following total hip replacement in highly dysplastic hips: a retrospective study

BACKGROUND

As a recognized cause of groin pain following total hip arthroplasty, iliopsoas tendonitis probably results from different factors. Given the anatomic disadvantage, dysplastic hips theoretically make acetabular component relatively retroverted or oversized, screws implanted frequently, and iliopsoas tendonitis more likely. However, the prevalence and mechanism of iliopsoas tendonitis following total hip replacement in dysplastic hips are not fully understood.

METHODS

One hundred and thirty-three total hip arthroplasties for Crowe type 2 to 4 dysplastic hips were compared with 126 total hip arthroplasties for hips without dysplasia in this study. Preoperative patient demographic data were well matched between the groups. Clinical and radiographic evaluations were performed.

RESULTS

A significantly higher frequency of protruded screws (24.8% vs 0), anterior overhang of acetabular components (30.8% vs 4.0%), and increased leg lengthening (3.6 [2.0-6.8] vs 0.5 [0-1.8]) was found in the dysplastic group (all p values < 0.05). However, the femoral offset and inclination and anteversion of acetabular components between the groups did not differ significantly. No difference in the prevalence of iliopsoas tendonitis was found between the groups. A new cause of iliopsoas tendonitis following total hip arthroplasty was detected in the dysplastic group. The iliopsoas tendonitis was irritated by an instable artificial femoral head.

CONCLUSIONS

The dysplastic hips did not present a higher incidence of postoperative iliopsoas tendonitis in this study. Iliopsoas tendonitis could be somewhat prevented by smaller size of acetabular components and soft tissue release in dysplastic hips, but irritated by an instable artificial femoral head.

An operative technique for psoas impingement following total hip arthroplasty: a case series of day case, extra articular, arthroscopic psoas tenotomy

PURPOSE

We present a prospective case series of patients undergoing an arthroscopic, extra-articular psoas tenotomy.

METHODS

From February 2009 to February 2017, 13 consecutive patients underwent day case, arthroscopic tenotomy. Patients were selected following clinical evidence of impingement and a diagnostic ultra-sound-guided steroid injection of the psoas bursa. The patient's mean age was 52.8 years ± 13.7 (29.1-82.7), mean ASA 1.8 and mean BMI 30.6 ± 8.5 kg/m². We detail the technique employed and patient outcomes to include FABER testing, manual hip flexion strength assessment and pain improvements.

RESULTS

The typical onset of impingement symptoms following THA was 4 months (2-24 months). 9 patients tested FABER negative and 62% (n = 8) were pain-free within 6-12 weeks. An average 20% (5-30%) reduction in hip flexion strength was seen post-arthroscopy. The mean follow-up was 2 years, (0.5-7 years). Regarding complications, one patient required revision surgery due to recurrence prompting a technique adaptation.

CONCLUSION

For psoas impingement following THA where non-operative measures are ineffective, we recommend extra-articular arthroscopic psoas tenotomy as a feasible operative strategy. This minimally invasive, day case, low-risk treatment option is beneficial in relieving impingement symptoms.

Total hip arthroplasty using stem-first technique with navigation: the potential of achievement of the optimal combined anteversion being a risk factor for anterior cup protrusion

PURPOSE

In the combined anteversion (CA) technique for total hip arthroplasty (THA) with a cementless stem, cup anteversion is strongly influenced by the native femoral anteversion. It is hypothesized that in cases with large native femoral anteversion, cup anteversion can be decreased, and anterior cup protrusion from the anterior edge of the acetabulum could occur due to the achievement of optimal CA. In this study, the accuracy of CA in THA with the CA technique using imageless navigation and the relationship between the protrusion of the anterior edge of cup and optimum CA was retrospectively evaluated.

METHODS

Ninety-seven patients (104 hips) who underwent primary THA by the CA technique using image-free navigation were enrolled in the study. The femoral stem was placed following the individual femoral anteversion so that the target cup anteversion could be determined following a mathematical formula (37 = femoral stem anteversion × 0.7 + cup anteversion). Results The resulting CA values effectively achieved accurate CA with 39.49 ± 5.03° postoperatively. On the other hand, anterior cup protrusion was measured by computed tomography image. A cup protrusion length of more than 3 mm was indicated for 60 cases (57.7%). All included patients were divided into two groups: Group 1 as protrusion positive and Group 2 as protrusion negative. In Group 1, preoperative femoral anteversion and postoperative stem anteversion were significantly higher, while postoperative cup anteversion was significantly lower. However, the postoperative CA value indicated no significant difference between the groups.

CONCLUSIONS

The CA (stem-first) technique with image-free navigated THA could effectively achieve accurate CA. On the other hand, a large number of cases revealed anterior cup protrusion due to the low cup anteversion.

Arthroscopic treatment of iliopsoas impingement syndrome after hip arthroplasty

BACKGROUND AND AIM OF THE WORK

Groin pain after hip arthroplasty (HA) ranges from 0.4% to 18.3%. Defining the cause of groin pain after HA can be difficult. Iliopsoas impingement (IPI) has been reported to be the underlying cause of groin pain in up to 4.4% of cases. The purpose of this study is to present arthroscopic surgical outcomes in the treatment of IPI after HA.

METHODS

Between September 2013 and March 2018, 13 patients, 11 total hip arthroplasty (THA), 1 hip endoprosthesis and 1 total hip resurfacing affected by groin pain due to unceasing iliopsoas tendinopathy for impingement after HA were treated arthroscopically. The patients underwent to physical examination, blood analysis, hip X-rays, bone scintigraphy and CT assessment. We performed the arthroscopic OUT-IN access to hip joint in all patients. VAS scale, Harris Hip Score (HHS) and Medical Research Council (MRC) scale were performed before surgery and during follow up at 1-3-6-12 months.

RESULTS

After 10 months of mean follow-up, average HHS and MRC scale improved significantly from preoperatively to postoperatively. No complications arose in our case series.

CONCLUSIONS

Hip arthroscopy after hip arthroplasty is supported in the literature for a variety of indications. Hip arthroscopy is a viable and reproducible technique in treatment of IPI, being less invasive than the classic open technique. This simple arthroscopic release provides satisfactory results and preserves HA function. Moreover an arthroscopic OUT-IN access proves good clinical outcomes, few complications and iatrogenic lesions.