Ultrasound-Guided Hip Procedures

The Anatomic Position of the Sciatic Nerve During Percutaneous Retrograde Posterior Column Fixation Is Determined by Hip Position

OBJECTIVES

There are multiple established patient positions for placement of a percutaneous retrograde posterior column screw for fixation of acetabulum fractures. The sciatic nerve is at risk of injury during this procedure because it lies adjacent to the start point at the ischial tuberosity. The purpose of this study was to define how the position of the sciatic nerve, relative to the ischial tuberosity, changes regarding the patient's hip position.

METHODS

In a cohort of 11 healthy volunteers, ultrasound was used to measure the absolute distance between the ischial tuberosity and the sciatic nerve. Measurements were made with the hip and knee flexed to 90 degrees to simulate supine and lateral positioning and with the hip extended to simulate prone positioning. In both positions, the hip was kept in neutral abduction and neutral rotation.

RESULTS

The distance from the lateral border of the ischial tuberosity to the medial border of the sciatic nerve was greater in all subjects in the hip-flexed position versus the extended position. The mean distance was 17 mm (range, 14-27 mm) in the hip-extended position and 39 mm (range, 26-56 mm) in the hip-flexed position ( P < 0.001).

CONCLUSIONS

The sciatic nerve demonstrates marked excursion away from the ischial tuberosity when the hip is flexed compared with when it is extended. The safest patient position for percutaneous placement of a retrograde posterior column screw is lateral or supine with the hip flexed to 90 degrees.

Ultrasound-guided injection of the hip: Cadaveric description for the lateral approach

BACKGROUND

Ultrasound (US)-guided intraarticular hip joint injections are commonly performed using an in-plane anterior approach, which has several limitations.

OBJECTIVE

To describe and report a "lateral" (lateral to medial) approach for US-guided intraarticular hip injection.

DESIGN

Cadaveric investigation.

SETTING

Academic institution, department of anatomy.

PARTICIPANTS

One cadaveric specimen.

METHODS

Both hips of a single cadaver were injected using the US-guided lateral approach. In the left hip, the needle was inserted and kept in situ. The right hip was injected with white-colored water-diluted latex dye. Subsequently, a layer-by-layer anatomical dissection was performed.

MAIN OUTCOME MEASURES

Presence and distribution of latex dye and location of needle tip within the joint capsule of the hip.

RESULTS

Anatomical dissection of the left and right hips confirmed the correct intraarticular position of the needle tip and the placement of the latex dye, respectively. During layer-by-layer dissection of the left hip, positions of the lateral cutaneous nerve and the lateral circumflex femoral artery were observed anterior to the needle, 30 mm for the nerve and 8 mm for the artery.

CONCLUSIONS

This preliminary study demonstrated that the US-guided lateral approach is a convenient technique to access the hip joint in a cadaveric specimen. Compared with the "classical" anterior technique, the lateral approach may provide several advantages, including improved needle visibility, theoretically decreased risk of vascular injury, and less risk of needle contamination. Because injury to the lateral epiphyseal arteries is possible when lateral approach is used, caution is required, especially in children. These preliminary conclusions will need to be validated in future/larger clinical studies.

Imaging-Guided Musculoskeletal Interventions in the Lower Limb

Imaging guidance is essential for musculoskeletal interventional procedures performed in the lower limb. A strong evidence supports the use of imaging guidance to improve safety, accuracy, and effectiveness of these interventions. Joints, tendons, bursae, and nerves can be effectively approached especially with ultrasound-guided injections. Here, we discuss evidence and technique of the most common image-guided musculoskeletal interventional procedures in the lower limb.

Postoperative Musculoskeletal Imaging and Interventions Following Hip Preservation Surgery, Deformity Correction, and Hip Arthroplasty

Total hip arthroplasty and hip preservation surgeries have substantially increased over the past few decades. Musculoskeletal imaging and interventions are cornerstones of comprehensive postoperative care and surveillance in patients undergoing established and more recently introduced hip surgeries. Hence the radiologist's role continues to evolve and expand. A strong understanding of hip joint anatomy and biomechanics, surgical procedures, expected normal postoperative imaging appearances, and postoperative complications ensures accurate imaging interpretation, intervention, and optimal patient care. This article presents surgical principles and procedural details pertinent to postoperative imaging evaluation strategies after common hip surgeries, such as radiography, ultrasonography, computed tomography, and magnetic resonance imaging. We review and illustrate the expected postoperative imaging appearances and complications following chondrolabral repair, acetabuloplasty, osteochondroplasty, periacetabular osteotomy, realigning and derotational femoral osteotomies, and hip arthroplasty.

Ultrasound-Guided Musculoskeletal Injections

Musculoskeletal injections serve a variety of diagnostic and therapeutic purposes, with ultrasonography (US) guidance having many advantages: no ionizing radiation, real-time guidance, high spatial resolution, excellent soft tissue contrast, and the ability to identify and avoid critical structures. Sonography can be cost effective and afford flexibility in resource-constrained settings. This article describes US-guided musculoskeletal injections relevant to many radiology practices and provides experience-based suggestions. Structures covered include multiple joints (shoulder, hip), bursae (iliopsoas, subacromial-subdeltoid, greater trochanteric), peripheral nerves (sciatic, radial), and tendon sheaths (posterior tibial, peroneal, flexor hallucis longus, Achilles, long head of the biceps). Trigger point and similar targeted steroid injections, as well as calcific tendinopathy barbotage, are also described.

How to Approach a Hip PARTI With Confidence: Ultrasound-Guided Parallel Transverse in-Plane Technique for Intra-articular Hip Interventions

The "parallel transverse in-plane" technique for ultrasound-guided intra-articular hip interventions ensures needle visualization for the entire procedure, with the needle clearly shown entering the joint. With the widely described longitudinal in-plane approach, needle visualization can be poor, necessitating reliance on tissue distortion, which can reduce user confidence and safety. The parallel transverse in-plane approach is invaluable in those with anterior thigh skin breakdown and where anterior access is contraindicated. The approach also allows a broad width of the synovium to be traversed and is therefore well suited to synovial biopsy. This short Technical Innovation highlights this alternative approach to hip joint intervention.

Selective periarticular blocks for postoperative pain after hip and knee arthroplasty

PURPOSE OF REVIEW

This review aims to provide an overview of selective periarticular blocks for postoperative pain after hip and knee arthroplasty and the current evidence for their use.

RECENT FINDINGS

Most interventional analgesia techniques for hip and knee arthroplasty result in a motor block and muscle weakness. Therefore, these are not well suited for fast-track protocols. In contrast, selective pericapsular infiltration techniques provide selective joint sensory block without an associated motor block. This facilitates postoperative pain management and avoids impairing ambulation and early rehabilitation.

SUMMARY

The pericapsular blocks of the hip (pericapsular nerve group block, iliopsoas plane block, hip block), genicular nerves block, and infiltration between the popliteal artery and the capsule of the knee play an increasingly important role in providing postoperative analgesia after hip and knee arthroplasty without impeding fast-track protocols.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part IV, hip

Objectives

Image-guided musculoskeletal interventional procedures around the hip are widely used in daily clinical practice. The need for clarity concerning the actual added value of imaging guidance and types of medications to be offered led the Ultrasound and the Interventional Subcommittees of the European Society of Musculoskeletal Radiology (ESSR) to promote, with the support of its Research Committee, a collaborative project to review the published literature on image-guided musculoskeletal interventional procedures in the lower limb in order to derive a list of clinical indications.

Methods

In this article, we report the results of a Delphi-based consensus of 53 experts who reviewed the published literature for evidence on image-guided interventional procedures offered in the joint and soft tissues around the hip in order of their clinical indications.

Results

Ten statements concerning image-guided treatment procedures around the hip have been collected by the panel of ESSR experts.

Conclusions

This work highlighted that there is still low evidence in the existing literature on some of these interventional procedures. Further large prospective randomized trials are essential to better confirm the benefits and objectively clarify the role of imaging to guide musculoskeletal interventional procedures around the hip.

Key Points

• Expert consensus produced a list of 10 evidence-based statements on clinical indications of image-guided interventional procedures around the hip.

• The highest level of evidence was only reached for one statement.

• Strong consensus was obtained for all statements.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-07997-5.

Surgical and Non-surgical Treatment Options for Piriformis Syndrome: A Literature Review

Context

Piriformis syndrome is a solely clinical diagnosis that often eludes the practitioner and goes underdiagnosed. PS is a pain syndrome and for those it affects, causes persistent pain and limits daily activity and work capacity. It is a form of deep gluteal syndrome that needs to be considered on the differential of low back pain as it comprises between 0.3% - 6% of all low back pain cases and is frequently underdiagnosed. Piriformis syndrome may be primary due anatomic anomalies or secondary, though the majority of cases are secondary to some insult. The objective of this manuscript is to provide a description of the epidemiology and presentation of piriformis as well as both non-operative and operative treatment options. We review all of the recent clinical evidence regarding the aforementioned therapies.

Evidence Acquisition

Literature searches were performed using the below MeSH Terms using Mendeley version 1.19.4. Search fields were varied until further searches revealed no new articles. All articles were screened by title and abstract. Decision was made to include an article based on its relevance and the list of final articles was approved three of the authors. This included reading the entirety of the article. Any question regarding the inclusion of an article was discussed by all authors until an agreement was reached.

Results

Medical management and physical therapy show some promise; however, when conservative treatment fails minimally invasive methods such as steroid injections, botulinum toxin injections, dry needling are all efficacious and there is substantial clinical evidence regarding these therapies. In those patients in which minimally invasive techniques do not result in an adequate relief of pain and return of function, endoscopic release can be considered. Endoscopic release is far superior to open release of the piriformis syndrome given the higher success and lower rate of complications.

Conclusions

Piriformis syndrome is an important differential diagnosis in the work up of lower back pain and should not be ruled out with proper examination and testing. Clinicians should consider medical management and conservative management in the initial treatment plan for piriformis syndrome. There are many options within the conservative management and the literature shows much promise regarding these. Physical therapy, steroid injections, botulinum toxin injections, and dry needling are all potentially effective therapies with few adverse effects. Surgical options remain as gold standard, but only when conservative management has failed and the symptoms are significant to affect daily living activities. Endoscopic decompression of the sciatic nerve with or without release of the piriformis muscle has a reported high likelihood of success and a low complication rate. Current literature supports the preference of the endoscopic approach over the open approach due to improved outcomes and decreased complications. Further research is to well define the metrics for the diagnosis of piriformis syndrome and may include a need to develop diagnostic criteria.

[Diagnostic algorithm "FAI and sports hernia" : Results of the consensus meeting for groin pain in athletes]

As a result of the complexity and diversity of diseases in the region of the groin, differentiation of the various soft-tissue and bone pathologies remains a challenge for differential diagnosis in routine clinical practice. In the case of athletes with pain localized in the area of the groin, femoroacetabular impingement (FAI) and athlete's groin must be considered as important causes of the groin pain, whereby the common occurrence of double pathologies further complicates diagnosis. Despite the importance of groin pain and its differential diagnoses in everyday clinical practice, there has been a lack of recognized recommendations for diagnostic procedure to date. To this end, a consensus meeting was held in February 2017, in which a group composed equally of groin and hip surgeons took part. With the formulation of recommendations and the establishment of a practicable diagnostic path, colleagues that are involved in treating such patients should be sensitized to this issue and the quality of the diagnosis of groin pain improved in routine clinical practice.

Ultrasound-Guided Hip Injections

The diagnosis of hip pain can be difficult to isolate because the discomfort can originate from several locations and compensatory pain patterns. Pain generators can include the intra- and extra-articular hip structures, the lumbar spine, the pelvic floor, or a combination of these. It can also be referred as pain from the bowel, bladder, or reproductive organs. Injections into and around the hip have become an important part of both diagnostic and nonsurgical treatment algorithm for hip pain. The proximity of the hip to important neurovascular structures, lack of palpable anatomic landmarks, and deep location of targets can make use of ultrasonography-guided injections ideal. These injections have been growing in popularity in the orthopedic community because ultrasonography allows for a real-time visualization of dynamic anatomy without any radiation exposure to the patient and physician. The use of ultrasonography has allowed for in-office image guidance with improved accuracy for more targeted and advanced procedures. The patient's response to these injections can help guide patient selection for surgery and allow for better pain control of the soft-tissue pathology that often accompanies intra-articular pathology. This article highlights the diagnostic and therapeutic value of ultrasonography-guided hip injections for an orthopedic practice. The focus is on sonographic anatomy, introduction to technique, common indications, and pearls and pitfalls of these procedures.

Arthroscopic techniques for treating ilio-psoas tendinopathy after hip arthroplasty

Impingement of hip arthroplasty components on soft tissues may adversely affect outcomes. An example is impingement of the cup on the ilio-psoas tendon, which has been reported in 0.4% to 8.3% of patients. Contributors to ilio-psoas tendon impingement (IPTI) can be categorised as anatomic (hypoplastic anterior wall), technical (inadequate anteversion and/or lower inclination, oversized cup, cement in contact with the tendon, and intra-muscular screw), and prosthetic (e.g., aggressive cup design, large-diameter head, resurfacing, and collared femoral prosthesis). IPTI manifests as groin pain, raising diagnostic challenges since this symptom lacks specificity. Physical findings of value for the diagnosis include pain exacerbation during active hip flexion, groin pain upon straight-leg raise to 30°, and/or snapping hip syndrome. Confirmation is then provided by ultrasonography and, most importantly, computed tomography. Once the diagnosis is confirmed, non-operative treatment combining physical therapy and local corticosteroid injections is prescribed. When these measures fail, endoscopic or arthroscopic surgery is generally effective. In patients with major cup malposition, revision of the cup is the preferred option, despite the higher complication rate. When cup position is adequate, ilio-psoas tenotomy can be performed either extra-articularly at the lesser trochanter (by endoscopy) or intra-articularly (by arthroscopy). The arthroscopic technique is more demanding but useful when the diagnosis is in doubt, as it allows examination of the prosthetic bearing surfaces. Both techniques and the risks inherent in each are discussed in detail. Tenotomy, whether performed endoscopically or arthroscopically, promptly provides good outcomes in over 85% of patients, usually with full recovery of hip flexor strength over time. These minimally invasive techniques, while as effective as conventional surgery, are associated with lower morbidity rates.

Ultrasound elastography findings in piriformis muscle syndrome

Background:

Piriformis muscle syndrome (PMS) is relatively less known and underestimated because it is confused with other clinical pathological conditions. Delays in its diagnosis may lead to chronic somatic dysfunction and muscle weakness.

Objective:

Here, we aimed to evaluate the diagnostic performance of the ultrasound elastography (UE) as an easy, less-invasive, and cost-effective method for early diagnosis of PMS.

Materials and Methods:

Twenty-eight cases clinically diagnosed as PMS at the outpatient clinic were evaluated by UE. The elastographic strain ratio was calculated by dividing the strain value of the subcutaneous fat tissue by the mean stress value of the muscle beneath. The diagnostic performances of the strain rate measures were compared using the receiver operating characteristic curve analysis.

Results:

Twenty-one (N = 21) cases were female, and seven (N = 7) of the cases were male. The mean age was 45 years (ranged 24–62 years). The strain rates of piriformis muscle (PM) and gluteus maximus (GM) muscles were significantly higher on the PMS-diagnosed side (P < 0.001). The cutoff value of UE strain ratio for the PM and GM were 0.878 [95% confidence interval (CI) 0.774–0.981] and 0.768 (95% CI 0.622–0.913), respectively, and the sensitivity and specificity values were, respectively, 80.95% and 85.71% for the PM, and they were, respectively, 85.71% and 66.67% for the GM.

Conclusion:

We showed that the muscle elasticity and tissue hardening increased on the problematic side both on PM and GM. UE may provide early diagnosis of PMS, thereby increasing the possibility of treatment with less invasive methods.

Arthroscopic Iliopsoas Fractional Lengthening

Background

Iliopsoas fractional lengthening (IFL) is performed on patients with symptomatic internal snapping. This condition is defined as painful and sometimes audible snapping of the iliopsoas (IP) tendon over the femoral head or iliopectineal line. Arthroscopic IFL is performed if the snapping is unresponsive to conservative treatment^1,2.

Description

Hip arthroscopy is performed with the patient in the supine position on a traction table. The portals used to access the joint capsule include standard anterolateral, mid-anterior, and distal anterolateral accessory (DALA) portals³. With a 70° arthroscope, diagnostic arthroscopy is conducted to assess the quality of labral tissue, acetabular and femoral cartilage surfaces, and the ligamentum teres. When indicated, supplementary procedures, such as acetabuloplasty, labral repair, or labral reconstruction⁴, are performed prior to IFL. With traction still applied, IFL is then performed from the central compartment at the level of the joint line. Exposure of the IP tendon is achieved with the use of a curved blade to extend the capsulotomy medially over the 3 o'clock position (right hip). Once the tendon can be appropriately visualized, a progressive and complete transverse cut is made in the tendinous portion, taking care to avoid the muscular portion. During this process, the anterolateral and mid-anterior portals serve as visualization and working portals, respectively⁵.

Alternatives

Prior to arthroscopic IFL for painful internal snapping, nonsurgical options^6,7 may include (1) physical therapy programs, (2) activity modification, (3) nonsteroidal anti-inflammatory drugs (NSAIDs), or (4) ultrasound-guided cortisone injections.

Does Iliopsoas Lengthening Adversely Affect Clinical Outcomes After Hip Arthroscopy? A Multicenter Comparative Study

BACKGROUND

Iliopsoas fractional lengthening (IFL) continues to be a controversial procedure in hip arthroscopy.

HYPOTHESIS

Patients who underwent arthroscopic surgery for femoroacetabular impingement (FAI) and a labral tear either with or without IFL would experience favorable outcomes, and there would be no difference in postoperative patient-reported outcomes (PROs) between the 2 groups at minimum 2-year follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data from July 2009 and April 2015 were retrospectively reviewed. Patients were eligible if they had hip arthroscopy for both FAI and labral tear treatment with IFL and without IFL. IFL was indicated for painful internal snapping. Minimum postoperative follow-up was set to 2 years. The authors calculated the modified Harris Hip Score, International Hip Outcome Tool-12, Hip Outcome Score-Activity of Daily Living Score, Hip Outcome Score-Sports Specific Subscale, Non-Arthritic Hip Score, visual analog scale for pain, patient satisfaction, minimal clinically important difference (MCID), and the percentage of patients who achieved patient acceptable symptomatic state (PASS). Revision surgeries and conversions to total hip arthroplasty (THA) were documented.

RESULTS

351 hips (307 patients) met the necessary inclusion criteria in the IFL cohort, with a mean ± SD follow-up time of 42.5 ± 18.1 months. For the control cohort, 392 hips (354 patients) were included, with a mean ± SD follow-up time of 43.9 ± 19.6 months. Both groups showed significant postoperative improvement in 2-year follow-up PROs. The group with iliopsoas lengthening showed comparable results to the control group with respect to PRO improvement, MCID, PASS, and rates of revision or THA conversion.

CONCLUSION

This comparative cohort study demonstrated that treatment of painful internal snapping syndrome with arthroscopic IFL, in the setting of FAI and a labral tear, is a safe procedure with good short- to mid-term follow-up results and associated improvement in PROs. Patients who underwent IFL showed similar outcomes compared with a control group treated for FAI and labral tear without IFL. In appropriately selected patients, arthroscopic IFL did not adversely affect clinical outcomes compared with patients who did not need IFL.

Ultrasound Diagnostic and Therapeutic Injections of the Hip and Groin

Hip and groin pain often presents a diagnostic and therapeutic challenge. The differential diagnosis is extensive, comprising intra-articular and extra-articular pathology and referred pain from lumbar spine, knee and elsewhere in the pelvis. Various ultrasound-guided techniques have been described in the hip and groin region for diagnostic and therapeutic purposes. Ultrasound has many advantages over other imaging modalities, including portability, lack of ionising radiation and real-time visualisation of soft tissues and neurovascular structures. Many studies have demonstrated the safety, accuracy and efficacy of ultrasound-guided techniques, although there is lack of standardisation regarding the injectates used and long-term benefit remains uncertain.

Endoscopic or arthroscopic iliopsoas tenotomy for iliopsoas impingement following total hip replacement. A prospective multicenter 64-case series

INTRODUCTION

Impingement between the acetabular component and the iliopsoas tendon is a cause of anterior pain after total hip replacement (THR). Treatment can be non-operative, endoscopic or arthroscopic, or by open revision of the acetabular component. Few studies have assessed these options. The present study hypothesis was that endo/arthroscopic treatment provides rapid pain relief with a low rate of complications.

METHODS

A prospective multicenter study included 64 endoscopic or arthroscopic tenotomies for impingement between the acetabular component and the iliopsoas tendon, performed in 8 centers. Mean follow-up was 8months, with a minimum of 6months and no loss to follow-up. Oxford score, patient satisfaction, anterior pain and iliopsoas strength were assessed at last follow-up. Complications and revision procedures were collated. Forty-four percent of patients underwent rehabilitation.

RESULTS

At last follow-up, 92% of patients reported pain alleviation. Oxford score, muscle strength and pain in hip flexion showed significant improvement. The complications rate was 3.2%, with complete resolution. Mean hospital stay was 0.8 nights. In 2 cases, arthroscopy revealed metallosis, indicating revision of the acetabular component. The only predictive factor was acetabular projection on oblique view. Rehabilitation significantly improved muscle strength.

CONCLUSION

Endoscopic or arthroscopic tenotomy for impingement between the acetabular component and the iliopsoas tendon following THR significantly alleviated anterior pain in more than 92% of cases. The low complications rate makes this the treatment of choice in case of failure of non-operative management. Arthroscopy also reorients diagnosis in case of associated joint pathology. Projection of the acetabular component on preoperative oblique view is the most predictive criterion, guiding treatment.

Efficacy of a single intra-articular injection of ultra-high molecular weight hyaluronic acid for hip osteoarthritis: a randomized controlled study

BACKGROUND

Viscosupplementation with hyaluronic acid (HA) is increasingly used for the treatment of hip osteoarthritis (OA). The purpose of this study was to compare the efficacy of intra-articular injections of an ultra-high molecular weight viscosupplement (UHMW-HA, Fermathron S) with a medium molecular weight hyaluronan (MMW-HA, Hyalubrix 60) in hip OA.

METHODS

Fifty-four patients with hip OA grade 3 on the Kellgren/Lawrence scale were randomized. All infiltrations were performed under ultrasound guidance. Evaluation was performed preoperatively and at 1, 3, 6 and 12 months after infiltration. Patients were clinically evaluated using Lequesne index, VAS and WOMAC score.

RESULTS

Fifty patients, including 27 in the MMW-HA group and 23 in the UHMW-HA group, completed the follow-up. No significant difference was found between the two groups in terms of VAS, WOMAC or Lequesne index preoperatively or at 1, 3, 6 and 12 months after viscosupplementation. A stratified analysis was performed to study the development over time of Lequesne index of patients aged ≤ 55 years, > 55 and, ≤ 70 years and > 70 years and Lequesne index was different between the three age-stratified subgroups only in the MMW-HA group. The subgroup of older patients showed a higher Lequesne index than the subgroups of younger patients (p < 0.05).

CONCLUSIONS

UHMW-HA is a safe and effective treatment for hip osteoarthritis. A single dose of UHMW-HA was as effective as two doses of MMW-HA resulting in similar reductions of pain and disability.

STUDY DESIGN

Multicenter, independent, prospective, randomized controlled trial with level of evidence 1.

A Case of Trigger-Point Injection-Induced Hypokalemic Paralysis

Patient: Male, 39

Final Diagnosis: Trigger-point induced hypokalemia

Symptoms: Bilateral lower extremity weakness

Medication: Epinephrine • Bupivacaine • Methylprednisolone

Clinical Procedure: Trigger-point Injection

Specialty: Nephrology and Radiology