Current concepts in the diagnosis and management of extra-articular hip impingement syndromes

Groin Pain Syndrome Italian Consensus Conference update 2023

Groin pain syndrome (GPS) is a controversial topic in Sports Medicine. The GPS Italian Consensus Conference on terminology, clinical evaluation and imaging assessment of groin pain in athletes was organized by the Italian Society of Arthroscopy in Milan, on 5 February 2016. In this Consensus Conference (CC) GPS etiology was divided into 11 different categories for a total of 63 pathologies. The GPS Italian Consensus Conference update 2023 is an update of the 2016 CC. The CC was based on a sequential, two-round online Delphi survey, followed by a final CC in the presence of all panelists. The panel was composed of 55 experts from different scientific and clinical backgrounds. Each expert discussed 6 different documents, one of which regarded the clinical and imaging definition of sports hernias, and the other 5 dealt with 5 new clinical situations thought to result in GPS. The panelists came to an agreement on the definition of a sports hernia. Furthermore, an agreement was reached, recognizing 4 of the 5 possible proposed pathologies as causes to GPS. On the contrary, the sixth pathology discussed did not find consensus given the insufficient evidence in the available scientific literature. The final document includes a new clinical and imaging definition of sports hernia. Furthermore, the etiology of GPS was updated compared to the previous CC of 2016. The new taxonomic classification includes 12 categories (versus 11 in the previous CC) and 67 pathologies (versus 63 in the previous CC).

Sex-specific bone and muscular morphological features in ischiofemoral impingement: A three-dimensional study

The study aimed to investigate how hip bone and muscular morphology features differ between ischiofemoral impingement (IFI) patients and healthy subjects among males and females. Three-dimensional models were reconstructed based on magnetic resonance imaging images from IFI patients and healthy subjects of different sexes. Bone morphological parameters and the cross-sectional area of the hip abductors were measured. The diameter and angle of the pelvis were compared between patients and healthy subjects. Bone parameters of the hip and cross-sectional area of the hip abductors were compared between affected and healthy hips. The comparison results of some parameters were significant for females but not males. For females, the comparison results of pelvis parameters showed that the anteroposterior diameter of the pelvic inlet (p = 0.001) and intertuberous distance (p < 0.001) were both larger in IFI patients than in healthy subjects. Additionally, the comparison results of hip parameters showed that the neck shaft angle (p < 0.001) and the cross-sectional area of the gluteus medius (p < 0.001) and gluteus minimus (p = 0.005) were smaller, while the cross-sectional area of the tensor fasciae latae (p < 0.001) was significantly larger in affected hips. Morphological changes in IFI patients demonstrated sexual dimorphism, including bone and muscular morphology. Differences in the anteroposterior diameter of the pelvic inlet, intertuberous distance, neck shaft angle, gluteus medius, and gluteus minimus may explain why females are more susceptible to IFI.

Ultrasound Assessment of Hip Subspine Bone Morphology Soft-tissue Correlates with Clinical Diagnosis of Impingement

PURPOSE

To determine the ultrasound imaging manifestations associated with subspine impingement (SSI), including the osseous and soft-tissue injuries adjacent to anterior inferior iliac spine (AIIS) and to investigate the diagnostic value of ultrasound for SSI.

METHODS

We retrospectively evaluated patients who attended the sports medicine department of our hospital and underwent arthroscopic treatment for femoroacetabular impingement (FAI) between September 2019 and October 2020, with preoperative hip joint ultrasound and computed tomography (CT) examination within 1 month before surgery. All of the FAI patients were divided into the SSI group and non-SSI group, according to the clinical and intraoperative findings. The preoperative ultrasound and CT findings were assessed. The sensitivity, specificity, and positive predictive value (PPV) of some indicators were calculated and compared. Multivariable logistic regression and receiver operating characteristic curve (ROC) were also used.

RESULTS

A total of 71 hips were included, with a mean age of 35.4 ± 10.4 years, 56.3% were women. Of these, 40 hips had clinically confirmed SSI. The bone morphology type III, heterogeneous hypoecho in anterosuperior joint capsule and the direct head of rectus femoris (dRF) tendon adjacent to AIIS on the Standard Section of the dRF in ultrasound were associated with SSI. Among them, the heterogeneous hypoecho in the anterosuperior joint capsule had the best diagnostic value for the SSI (85.0% sensitivity, 58.1% specificity, AUC = 0.681). The AUC of the ultrasound composite indicators was 0.750. The AUC and PPV of CT low-lying AIIS for the SSI diagnosis was 0.733 and 71.7%, which could be improved when CT was combined with the ultrasound composite indicators with AUC = 0.831 and PPV = 85.7%.

CONCLUSIONS

Bone morphology abnormalities and soft-tissue injuries adjacent to the AIIS through sonographic evaluation were associated with SSI. Ultrasound could be used as a feasible method to predict SSI. The diagnostic value for SSI could be improved when ultrasound is combined with CT.

LEVEL OF EVIDENCE

Level IV, case series.

Subspine femoroacetabular impingement: retrospective study of a series of patients treated by hip arthroscopic resection

BACKGROUND

Femoroacetabular impingement syndrome (FAIS) is a common hip pathology that causes pain and functional limitation in young patients. subspine femoroacetabular impingement (SFAI) is an increasingly diagnosed extra-articular subtype that occurs from mechanical conflict of the anteroinferior iliac spine (AIIS) with the cervico-diaphyseal junction during hip flexion, which is poorly described in the literature.

QUESTIONS/PURPOSES

We aimed to describe the clinical, functional, and radiological results of the arthroscopic treatment of a group of patients with SFAI treated in our Hip Unit.

STUDY DESIGN

Case series.

METHODS

We present a retrospective study of ten patients with SFAI treated between 2013 and 2020 with arthroscopic resection. Clinical results were assessed with scales such as visual analog scale (VAS); modified Harris Hip Score (mHHS), and Hip disability and Osteoarthritis Outcome Score (HOOS). Radiological results were assessed with radiological measurements, magnetic resonance imaging (MRI), and computed tomography (CT) reconstructions.

RESULTS

Six patients had a Type III AIIS and four of them had Type II. Two patients had previously been surgically treated for FAIS. The range of motion improved in flexion from 107 ± 11 degrees before surgery to 127.5 ± 6 degrees (p = 0.005). MHHS improved from 48.1 (38-75.3) before surgery to 83.1 (57-91) (p = 0.007) and HOOS improved from 65.2 (58-75) to 89 (68.1-100) (p = 0.007). VAS improved from 7.3 (5-9) pre-surgical to 2.5 (0-8) post-surgical (p = 0.005). We did not have significant complications except for an asymptomatic case of heterotopic ossification (Brooker I).

CONCLUSION

Arthroscopic decompression of AIIS in SFAI patients is a safe procedure that provides satisfactory short-term functional results, improving clinical symptoms, function, sports performance, and range of motion in our study.

Iliopsoas tendonitis after total hip arthroplasty : an improved detection method with applications to preoperative planning

AIMS

Iliopsoas impingement occurs in 4% to 30% of patients after undergoing total hip arthroplasty (THA). Despite a relatively high incidence, there are few attempts at modelling impingement between the iliopsoas and acetabular component, and no attempts at modelling this in a representative cohort of subjects. The purpose of this study was to develop a novel computational model for quantifying the impingement between the iliopsoas and acetabular component and validate its utility in a case-controlled investigation.

METHODS

This was a retrospective cohort study of patients who underwent THA surgery that included 23 symptomatic patients diagnosed with iliopsoas tendonitis, and 23 patients not diagnosed with iliopsoas tendonitis. All patients received postoperative CT imaging, postoperative standing radiography, and had minimum six months' follow-up. 3D models of each patient's prosthetic and bony anatomy were generated, landmarked, and simulated in a novel iliopsoas impingement detection model in supine and standing pelvic positions. Logistic regression models were implemented to determine if the probability of pain could be significantly predicted. Receiver operating characteristic curves were generated to determine the model's sensitivity, specificity, and area under the curve (AUC).

RESULTS

Highly significant differences between the symptomatic and asymptomatic cohorts were observed for iliopsoas impingement. Logistic regression models determined that the impingement values significantly predicted the probability of groin pain. The simulation had a sensitivity of 74%, specificity of 100%, and an AUC of 0.86.

CONCLUSION

We developed a computational model that can quantify iliopsoas impingement and verified its accuracy in a case-controlled investigation. This tool has the potential to be used preoperatively, to guide decisions about optimal cup placement, and postoperatively, to assist in the diagnosis of iliopsoas tendonitis.Cite this article: Bone Jt Open 2023;4(1):3-12.

No evidence exists on outcomes of non-operative management in patients with femoroacetabular impingement and concomitant Tönnis Grade 2 or more hip osteoarthritis: a scoping review

PURPOSE

The purpose of this scoping review was to assess the outcomes of all the non-operative modalities of management for femoroacetabular impingement (FAI) and concomitant osteoarthritis (OA) Tönnis Grade 2 or more.

METHODS

A systematic search of PubMed was performed from inception to December 1st 2021 for literature on outcomes of non-operative management strategies for young adults with symptomatic FAI using the PRISMA Extension for Scoping Reviews guidelines. Cohorts investigating FAI and concomitant hip OA Tönnis Grade 2 or more were considered eligible. Studies not written in English or German, below level 4 evidence, and reviews were excluded. A secondary analysis for FAI without OA stratification was conducted after the initial screening to allow identification of available non-operative interventions.

RESULTS

No study reported outcomes separately for non-operative management of FAI with Tönnis Grade 2 OA or more and as such, did not fulfil the inclusion criteria. A secondary analysis included 24 studies that reported on outcomes for non-operative interventions for FAI irrespective of the degree of degeneration. Three studies investigated the efficacy of hyaluronic acid injection, 5 reports investigated corticosteroid injections, 2 studies evaluated the outcomes of hip bracing and 16 studies included a physiotherapy programme. Associations between the aforementioned interventions were analysed. There is level I evidence supporting the efficacy of activity modification and hip-specific physiotherapy for FAI and mild OA. Core-strengthening exercises are prevalent amongst successful regimens in the literature. Contradictory evidence questions the efficacy of hip bracing even for short-term outcomes. Corticosteroid injections have mostly failed in intention-to treat analyses but may be valuable in delaying the need for surgery; further studies are warranted. Reports on outcomes following hyaluronic acid injections are contradictory.

CONCLUSION

No evidence exists on outcomes following non-operative management of FAI with concomitant Tönnis Grade 2 or more OA of the hip. Further studies are required and should explore the non-operative interventions that were employed for FAI and milder OA. There is strong evidence for a hip-specific physiotherapy program including activity modification and core strengthening exercises. Adjunct interventions such as corticosteroid injections and NSAID consumption may be valuable in delaying the need for surgery.

LEVEL OF EVIDENCE

Level IV.

The narrow subspine space and relatively large labrum are radiographic features of subspine impingement: a case-control study

Background

Subspine impingement is considered a source of residual hip symptoms after primary hip arthroscopy, and the role of the subspine space and soft tissue is not clear. The purpose of this study was to analyze the relationship between the subspine space and labrum size in subspine impingement patients.

Methods

We performed a retrospective study of patients with femoroacetabular impingement between July 2016 and July 2020. Sixteen patients without hip symptom relief after primary hip arthroscopic treatment of femoroacetabular impingement and undergoing revision surgery for anterior inferior iliac spine compression were included as the study group. Forty-eight matched patients who underwent only primary surgery and whose hip discomfort was relieved without a diagnosis of subspine impingement were included as the control group. The patients’ preoperative computerized tomography data were reviewed, and the anterior inferior iliac spine dimensions and the size of the subspine space were measured. The size of the labrum at the 11:30, 1:30, and 3 o’clock positions was measured with the use of magnetic resonance imaging. The ratio of the subspine space to the labrum was also calculated.

Results

There was no significant difference in anterior inferior iliac spine dimensions between these two groups (p > 0.05). A relatively narrow subspine space was found in the study group, especially in the direction of the anterior inferior iliac spine. Compared with the control group, subspine impingement patients were identified with larger labrums at 11:30 (8.20 ± 1.95 mm vs. 6.81 ± 0.50 mm, p = 0.016), 1:30 (7.83 ± 1.61 mm and 6.25 ± 0.78 mm, p = 0.001) and 3:00 (9.50 ± 1.73 mm vs. 7.48 ± 0.99 mm, p = 0.001). A relative mismatch between the subspine space and the labrum was also identified in the study group. The ratios of the labrum width to the subspine area were significantly larger in the study group than in the control group.

Conclusion

This study reported potential additional criteria for subspine impingement—a large labrum and a relatively narrow subspine space—instead of abnormal anterior inferior iliac spine dimensions. For those with a large labrum and narrow subspine space, the diagnosis of subspine impingement should be carefully made, and arthroscopic anterior inferior iliac spine decompression may be important.

Endoscopic Ischial Tuberosity Osteophyte Resection for Treatment of Ischiofemoral Impingement: A Case Report

Ischiofemoral impingement is a distinct pathologic finding with abnormal osseous contact between the ischium and the lesser trochanter of the femur. Lesser trochanter excision has been recommended for recalcitrant ischiofemoral impingement through an open or endoscopic approach; however, no study has included ischial tuberosity osteophyte resection and refixation of the hamstring tendon. We report an endoscopic procedure involving ischial tuberosity osteophyte resection with refixation of the partially detached hamstring insertion through a posterior approach in the prone position. Using this technique, it is easier to reach the lesion and less likely to injure the sciatic nerve. The postoperative pain score (visual analogy score) was significantly decreased, the modified Harris hip score increased from 39 preoperatively to 86 postoperatively, and there was no adverse effect on the hamstring tendon.

MRI findings of ischiofemoral impingement after total hip arthroplasty are associated with increased femoral antetorsion

BACKGROUND

Ischiofemoral impingement (IFI) is a known complication after total hip arthroplasty (THA).

PURPOSE

To assess if increased postoperative (FA) is associated with magnetic resonance imaging (MRI) findings of IFI.

MATERIAL AND METHODS

In 221 patients with THA, two independent readers measured FA, ischiofemoral space (IFS), quadratus femoris space (QFS), edema, and fatty infiltration of quadratus femoris muscle. Three sets of IFI-imaging features were defined: acute IFI (set 1): IFS ≤15 mm or QFS ≤10 mm and edema in the quadratus femoris muscle; chronic IFI (set 2): IFS ≤15 mm or QFS ≤10 mm and fatty infiltration of quadratus femoris muscle Goutallier grade ≥2; acute and chronic IFI (set 3) with both criteria applicable. For each set, FA angles were compared between positive findings of IFI and negative findings of IFI. The t-test for independent samples tested statistical significance.

RESULTS

In 7.2% (16/221) of patients, findings of IFI (IFS ≤15 mm or QFS ≤10 mm and edema, n = 1; fatty infiltration, n = 9; or both, n = 6) were observed. In women, 11.4% (14/123) exhibited findings of IFI compared to 2.0% (2/98) in men. Comparison in set 1 (n = 7): mean antetorsion of 23.9° ± 9.8° (findings of acute IFI) compared to 14.4° ± 9.7° (P = 0.01). Comparison in set 2 (n = 15): mean antetorsion of 16.2° ± 6.3° (findings of chronic IFI) compared to 14.5° ± 9.9° (P = 0.49). Comparison in set 3 (n = 6): mean antetorsion of 20.4° ± 3.8° (findings of acute and chronic IFI) compared to 14.5° ± 9.9° (P = 0.01).

CONCLUSION

After THA, high postoperative FA is associated with MRI findings of acute as well as acute and chronic IFI. Findings of IFI were commonly seen in women.

Incidence of heterotopic ossification following hip arthroscopy is low: considerations for routine prophylaxis

PURPOSE

This scoping review aims to map and summarise the available literature on heterotopic ossification (HO) following hip arthroscopy, with particular focus on incidence, distribution as per Brooker classification, efficacy of prophylactic measures and factors that may influence the likelihood of production of HO.

METHODS

A computer-based search was performed on PubMed, Embase, Emcare, Cinahl, ISI web of science and Scopus using the terms 'heterotopic ossification' and 'hip arthroscopy'. Articles reporting heterotopic ossification following hip arthroscopy for any condition were included after two-stage title/abstract and full-text screening.

RESULTS

Of the 663 articles retrieved, 45 studies were included. The proportion of patients with HO ranged from 0 to 44%. The majority of the cases were either Brooker grade I or II. Of the six studies investigating the effect of NSAID prophylaxis, five reported a significantly lower incidence of heterotopic ossification associated with its use. Weak evidence suggests that an outside-in arthroscopic approach, no capsular closure, male sex and mixed cam and pincer resection may be associated with an increased risk of HO.

CONCLUSION

Although there is a large variation in rates of HO following hip arthroscopy in the current literature, the majority of studies report a low incidence. Evidence exists advocating the administration of post-operative NSAIDs to reduce the incidence of HO following hip arthroscopy. This, combined with the low risk of complications, means there is a favourable risk-benefit ratio for prophylactic NSAID used in HA. Future research should work to identify patient clinical and demographic factors which may increase the risk of development of HO, allowing clinicians to risk stratify and select only specific patients who would benefit from receiving NSAID prophylaxis.

Ischiofemoral space dimensions for ischiofemoral impingement: is it different in children?

OBJECTIVE

This study intended to analyze alterations in ischiofemoral space (IFS) dimensions in normal children between the ages of 1 and 18 years for the ischiofemoral impingement.

MATERIALS AND METHODS

This study retrospectively focused on computed tomography images of 360 hips of 180 (90 boys and 90 girls) pediatric subjects (mean age: 9.50 ± 5.20 years, range: 1-18 years) without any hip disorders to measure IFS, femoral neck angle (FNA), and ischial angle (IA).

RESULTS

Mean IFS, FNA, and IA were measured as 14.64 ± 7.24 mm, 34.61 ± 11.47°, and 131.52 ± 4.22°, respectively. IFS increased in children aged between 1 and 18 years, whereas FNA and IA decreased. IFS was similar in infancy and early childhood periods but then increased up to postpubescent period. FNA decreased proportionally from birth, whereas IA decreased in an irregular pattern. Linear functions were detected as y = 3.451 + 1.178 × years for IFS, as y = 48.555 - 1.468 × years for FNA, and as y = 132.535 - 0.107 × years for IA.

CONCLUSION

Our findings indicate that IFS tends to increase in size with age during childhood but decreases with further aging. Therefore, age-specific values for IFS, FNA, and IA may be beneficial for clinicians and radiologists for the diagnosis of ischiofemoral impingement.

Ischiofemoral impingement: the evolutionary cost of pelvic obstetric adaptation

The risk for ischiofemoral impingement has been mainly related to a reduced ischiofemoral distance and morphological variance of the femur. From an evolutionary perspective, however, there are strong arguments that the condition may also be related to sexual dimorphism of the pelvis. We, therefore, investigated the impact of gender-specific differences in anatomy of the ischiofemoral space on the ischiofemoral clearance, during static and dynamic conditions. A random sampling Monte-Carlo experiment was performed to investigate ischiofemoral clearance during stance and gait in a large (n = 40 000) virtual study population, while using gender-specific kinematics. Subsequently, a validated gender-specific geometric morphometric analysis of the hip was performed and correlations between overall hip morphology (statistical shape analysis) and standard discrete measures (conventional metric approach) with the ischiofemoral distance were evaluated. The available ischiofemoral space is indeed highly sexually dimorphic and related primarily to differences in the pelvic anatomy. The mean ischiofemoral distance was 22.2 ± 4.3 mm in the females and 29.1 ± 4.1 mm in the males and this difference was statistically significant (P < 0.001). Additionally, the ischiofemoral distance was observed to be a dynamic measure, and smallest during femoral extension, and this in turn explains the clinical sign of pain in extension during long stride walking. In conclusion, the presence of a reduced ischiofemroal distance and related risk to develop a clinical syndrome of ischiofemoral impingement is strongly dominated by evolutionary effects in sexual dimorphism of the pelvis. This should be considered when female patients present with posterior thigh/buttock pain, particularly if worsened by extension. Controlled laboratory study.

3D MRI of the Hip Joint: Technical Considerations, Advantages, Applications, and Current Perspectives

Magnetic resonance imaging (MRI) is a common choice among various imaging modalities for the evaluation of hip conditions. Conventional MRI with two-dimensional acquisitions requires a significant amount of time and is limited by partial-volume artifacts and suboptimal fluid-to-cartilage contrast. Recent hardware and software advances have resulted in development of novel isotropic three-dimensional (3D) single-acquisition protocols that cover the volume of the entire hip and can be reconstructed in arbitrary planes for submillimeter assessment of bony and labro-cartilaginous structures in their planes of orientation. This technique facilitates superior identification of small labral tears and other hip lesions with better correlations with arthroscopy. In this review, we discuss technical details related to 3D MRI of the hip, its advantages, and its role in commonly encountered painful conditions that can be evaluated with great precision using this technology. The entities described are femoroacetabular impingement with acetabular labral tears, acetabular dysplasia, avascular necrosis, regional tendinopathies and tendon tears, bursitis, and other conditions.

Deep Gluteal Syndrome: A Pain in the Buttock

ABSTRACT

While buttock pain is a common complaint in sports medicine, deep gluteal syndrome (DGS) is a rare entity. DGS has been proposed as a unifying term referring to symptoms attributed to the various pain generators located in this region. While not all-inclusive, the diagnosis of DGS allows for focus on pathology of regionally associated muscles, tendons, and nerves in the clinical evaluation and management of posterior hip and buttock complaints. An understanding of the anatomic structures and their kinematic and topographic relationships in the deep gluteal space is pivotal in making accurate diagnoses and providing effective treatment. Because presenting clinical features may be unrevealing while imaging studies and diagnostic procedures lack supportive evidence, precise physical examination is essential in obtaining accurate diagnoses. Management of DGS involves focused rehabilitation with consideration of still clinically unproven adjunctive therapies, image-guided injections, and surgical intervention in refractory cases.

Pain relief and good functional outcomes after hip endoscopy via posterior approach in patients with ischiofemoral impingement

PURPOSE

Ischiofemoral impingement is considered to be an uncommon and difficult pathology to diagnose with respect to hip pain etiology. The objective was to describe the clinical results of endoscopic lesser trochanter resection via a posterior approach in patients with Ischiofemoral impingement.

METHODS

This was a retrospective observational study of consecutive patients with Ischiofemoral impingement, who underwent endoscopic resection of the lesser trochanter via a posterior approach, between 2015 and 2018. Clinical results were evaluated using the ischiofemoral impingement test, long-stride walking test, modified Harris Hip Score (mHHS) and the Oxford scale to assess the strength of the iliopsoas muscle as well as the presence of complications. Preoperative and postoperative ischiofemoral space was measured to assess whether the resection of the lesser trochanter was adequate.

RESULTS

16 hips in 13 patients (mean age: 34.4 ± 12.1 years, 11 women) with a follow-up period between 24 and 59 months were included. Preoperative ischiofemoral space ranged from 6.4 to 22.4 mm, a measure > 17.0 mm was achieved in 15 hips without the presence of pain in IFI test and long-strides walking test. Function improved postoperatively, as reflected by a higher mean mHHS (preoperative: 44.6 ± 21.5, postoperative: 81.2 ± 15.1, p < 0.05). After surgery, the strength of the iliopsoas muscle was not decreased compared to the preoperative measure. Three complications were reported, including two cases that required revision surgery.

CONCLUSIONS

Endoscopic resection of the lesser trochanter via posterior approach provides satisfactory outcomes with symptom relief and good functional results in patients with Ischiofemoral impingement. It is important to discuss the benefits and risks when offering this treatment choice.

LEVEL OF EVIDENCE

Level IV.

Complications of Hip Endoscopy in the Treatment of Subgluteal Space Pathologies

PURPOSE

To assess complications of hip endoscopy in patients with subgluteal space pathologies.

METHODS

This was a retrospective study of patients diagnosed with sciatic nerve entrapment (SNE), ischiofemoral impingement (IFI), and rupture of the proximal origin of the hamstring muscles (RHM) who underwent a hip endoscopy from January 2012 to December 2018, after a minimum of 3 months of conservative management without satisfactory results. Complications were documented and graded using the adapted system of Clavien-Dindo. Revision surgeries were classified as treatment failures. Function was evaluated by the Western Ontario McMaster Universities Osteoarthritis Index before and 12 months after the surgical procedure.

RESULTS

A total of 97 hips with subgluteal space pathologies were treated with hip endoscopy. This total consisted of 77 hips with SNE, 5 with IFI, 12 with SNE + IFI, and 3 hips with RHM. Minor (Clavien-Dindo I-II) and major (Clavien-Dindo III-V) complications occurred in 7.22% (7) (95% confidence interval 3.54%-14.15%) and 12.37% (12) (95% confidence interval 7.22%-20.39%). Grade II, III, and IV complications were reported in 7.22% (7), 7.22%, and 5.15% (5) hips, respectively. Temporary nerve injury of the sciatic nerve, hematoma, and permanent nerve injury of the posterior femoral cutaneous nerve were the most common grade II, grade III, and grade IV complications, respectively. The revision rate was 6.19% (6) and entrapment of the sciatic nerve was the main cause of reoperation. No statistically significant differences were found between cases with and without complications in the Western Ontario McMaster Universities Osteoarthritis Index scores evaluated before and after surgery (P > .05).

CONCLUSIONS

A high rate of complications associated with hip endoscopy were observed in patients with SNE, IFI, and RHM. Sciatic nerve and posterior femoral cutaneous nerve injury were the most frequent events.

LEVEL OF EVIDENCE

IV, case series type.

The case of 'A Rhino Horn': case report and proposal for modification to the Hetsroni and Kelly classification

Subspine impingement syndrome by definition involves a prominent antero-inferior iliac spine (AIIS) which can lead to impingement on the femoral neck thereby causing symptoms. We present the case of a 22-year-old semi-professional athlete who presented with a Type III AIIS morphology leading to subspine impingement syndrome and was managed via a mini open anterior approach. Radiological examination revealed a fairly prominent left AIIS resembling the 'horn of a rhino' extending to the trochanteric region anteriorly. A mini-anterior surgical approach was utilized for the resection of the 'rhino horn' and the rectus femoris was reattached. The patient remained asymptomatic at the one-year follow-up and had resumed weightlifting. Following this case, we propose a new classification of the type III AIIS morphology in view of the clinical presentation. The AIIS type III-Standard represents an extension from the acetabular rim to less than 1 cm (type III-S) and type III-Large, with an extension from the acetabular rim beyond 1 cm (type III-L). The type III-L will further be divided into two groups based on its relation to the ilium, type III-Lr ('rib shape') and type III-Lrh ('rhino horn').

Outcomes of Hip Arthroscopy in Patients with Femoroacetabular Impingement and Concomitant Tönnis Grade II Osteoarthritis or Greater: Protocol for a Systematic Review

Introduction

Outcomes of hip arthroscopy for femoroacetabular impingement and concomitant moderate- to advanced hip osteoarthritis (Tönnis Grade II or greater) is still a matter of debate as findings in the literature are controversial. This study aims to investigate whether hip arthroscopy is effective in treating patients with femoroacetabular impingement and Tönnis hip osteoarthritis Grade II or greater.

Methods and Analysis

The protocol follows the PRISMA-P guidelines. The systematic review is registered in the International Prospective Register for Systematic Reviews and Meta-analysis (PROSPERO) under the registration number: CRD42020210936. The search will include multiple databases: MEDLINE, EMBASE, Web of Science Core Collection and Cochrane library. The screening and selection process will be performed by two independent researchers based on predefined criteria. All studies published in English or German from inception to 1^st of December 2020 that investigated outcomes of hip arthroscopy in patients with Tönnis grade II or greater of hip osteoarthritis will be considered eligible. The risk of bias and quality of articles will be assessed using the MINORS tool. Methodological inconsistency and heterogeneity will be explored using the I² test. This assessment will be used to provide recommendations using the GRADE system.

Ethics and Dissemination

Separate ethical approval is not required. This study will be a comprehensive and rigorous systematic review on all published articles reporting on outcomes of hip arthroscopy for femoroacetabular impingement and concomitant hip osteoarthritis Tönnis Grade II or greater. It will explore patient reported outcomes as well as radiological outcomes, complications, rates of revision surgery and rates of conversion to total hip replacement (THR). Results of the current review will be published in a peer-reviewed scientific journal and disseminated on research platforms according to copyright rules and rights.

Highlights

Hip arthroscopy is used to treat femoroacetabular impingement and is effective in patients that have concomitant hip osteoarthritis Tönnis Grade 0 or 1.Outcomes of hip arthroscopy in patients with femoroacetabular impingement and in moderate to advanced osteoarthritis - Tönnis Grade 2 or greater, is a matter of debate.The purpose of the current systematic review is to elucidate, stratify and critical appraise the current evidence on outcomes in this patient subpopulation.

[Ischiofemoral impingement syndrome: Report of an unusual case]

Ischiofemoral impingement syndrome is usually underdiagnosed; this syndrome forms part of the differential diagnoses to be included in hip pain. It was initially described with surgical procedures but, with the passage of time, various medical entities have been described, as well as techniques and postures that can aggravate this syndrome, which can even be associated with neurological involvement. Current treatment is initially conservative, consisting of rest, analgesia, cold and progressive exercises aimed at the lumber and gluteal muscles and lower extremities but there is no established standard of care.

The Role of Hip Joint Clearance Discrepancy as Other Clinical Predictor of Reinjury and Injury Severity in Hamstring Tears in Elite Athletes

Hamstring tear injuries (HTI) are the most prevalent injuries in athletes, with high reinjury rates. To prevent reinjury and reduce the severity of injuries, it is essential to identify potential risk factors. Hip characteristics are fundamental to optimal hamstring function. We sought to investigate the role of hip joint clearance discrepancy (JCD) as a risk factor for HTI and a clinical predictor of risk of reinjury and injury severity. A cross-sectional, retrospective study was performed with elite athletes (n = 100) who did (n = 50) and did not (n = 50) have a history of injury. X-rays were taken to assess JCD. We reviewed muscular lesions historial, and health records for the previous 5 years. Significant differences were found in injury severity (p = 0.026; ŋ²p = 0.105) and a number of injuries (p = 0.003; ŋ²p = 0.172). The multivariate analysis data indicated that JCD was significantly associated with the number of injuries and their severity (p < 0.05). In the stepwise regression model, JCD variability explained 60.1% of the number of injuries (R² 0.601) and 10.5% of injury severity (R² 0.0105). These results suggest that JCD could play an important role as a risk factor for HTI and also as a clinical predictor of reinjury and injury severity.

Knee Flexion Angle Following Total Knee Arthroplasty Relates to a Preoperative Range of Motion of the Hip

BACKGROUND

Many factors have been reported to affect postoperative range of knee flexion after total knee arthroplasty (TKA); however, no study has reported the impact of preoperative range of motion of the hip to the postoperative flexion angle of the knee thus far.

METHODS

Of 38 consecutive patients who underwent posterior-stabilized TKA, we assessed 21 patients after excluding 17 patients who met exclusion criteria. The range of motion of the knee and the hip, age, body-mass index, serum albumin level, HbA1c, Kellgren-Lawrence grade, knee extension strength and radiological femorotibial angle as well as postoperative knee flexion angle at three months were evaluated. The preoperative data and the knee flexion angle at three months after TKA were compared using Spearman's rank correlation coefficient.

RESULTS

Knee flexion angle at three months after TKA was positively correlated with preoperative flexion (ρ = 0.616, p = 0.007) and external rotation angle (ρ = 0.576, p = 0.012) of the hip as well as preoperative knee flexion angle (ρ = 0.797, p = 0.001). There were no correlations between postoperative knee flexion angle and other preoperative data.

CONCLUSIONS

Patients with restricted flexion and/or external rotation of the hip may have contractures of Gluteus maximus, Gluteus medius and Tensor fasciae latae, which can cause hypertension of iliotibial tract. It may cause decreased internal rotation of the tibia when the knee is flexed, which affects postoperative knee flexion angle, thus limited flexion and/or external rotation of the hip might restrict knee flexion angle following TKA.

Assessment of the duration and effectiveness of intra-articular lidocaine injections for groin pain in patients with labral tears involving early osteoarthritis

Introduction: Intra-articular lidocaine injections have been used to confirm the hip pathology and may predict the efficacy of arthroscopic surgery. We have routinely performed the injections as a surgical indicator. The aim of this study was to assess the duration and effectiveness of these diagnostic intra-articular lidocaine injections on groin pain in patients with labral tears involving early osteoarthritis. Methods: A total of 113 patients were included in this study. All patients received one injection of 10 ml of 1% lidocaine into the hip joint under fluoroscopy. The duration and effectiveness of the injection were assessed 2 weeks after the injection and at a minimum of 1 year of follow-up. The effect of the injection was graded as 0: unchanged or worse; 1: an effect only on the day of injection; 2: the effect lasted a few days; 3: the effect lasted about a week; and 4: symptom remission. In addition, we recorded whether hip arthroscopic surgery was eventually performed. Results: The effect was rated as 0 in 19 patients (16.8%), as 1 in 30 patients (26.5%), as 2 in 38 patients (33.6%), as 3 in 13 patients (11.5%), and as 4 in 13 patients (11.5%). Seventy-two patients (63.7%) underwent hip arthroscopic surgery. No relationship with patients’ characteristics was found. Conclusion: In total, 83% of patients experienced some effect of the lidocaine injection. Furthermore, 11.5% of patients experienced complete remission of their symptoms.

Pathogenesis and contemporary diagnoses for lateral hip pain: a scoping review

PURPOSE

Recent advances in diagnostic imaging techniques and soft tissue endoscopy now allow for precise diagnosis and management of extra-articular hip pathology. The aim of this scoping review is to present an evidence-based update of the relevant literature focussing only on the pathoanatomy, clinical assessment and the diagnosis of pathology in the peritrochanteric space.

METHODS

A literature search was performed on PubMed to include articles which reported on the anatomy and diagnosis of greater trochanteric pain syndrome, trochanteric bursitis, gluteus medius tears and external snapping hip syndrome.

RESULTS

A total of 542 studies were identified, of which 49 articles were included for full text analysis for the scoping review. Peritrochanteric space pathology can be broadly classified into (1) greater trochanteric pain syndrome (GTPS), (2) abductor tears and (3) external snapping hip syndrome. Anatomically, gluteus medius, gluteus minimus and tensor fascia lata work in conjunction to abduct and internally rotate the hip. The anterolateral part of the gluteus medius tendon is more prone to tears due to a thin tendinous portion. Increased acetabular anteversion has also been shown to be associated with gluteal and trochanteric bursitis. In terms of clinical examination, tests which were found to be most useful for assisting in the diagnoses of lateral hip pain were the single-leg stance, resisted external derotation of the hip, hip lag sign and the Trendelenburg's test. Dynamic ultrasound along with guided injections and MRI scan do assist in differentiating the pathology and confirming the diagnosis in patients presenting with lateral hip pain. Finally, the assessment of baseline psychological impairment is essential in this group of patients to ensure outcomes are optimised.

CONCLUSION

Lateral hip pain used to be a poorly defined entity, but advances in imaging and interest in sports medicine have led to a better understanding of the pathology, presentation and management of this cohort of patients. A thorough appreciation of the anatomy of the abductor musculature, specific clinical signs and imaging findings will lead to an appropriate diagnosis being made and management plan instituted.

LEVEL OF EVIDENCE

IV.

Clinico-radiological review of peripheral entrapment neuropathies - Part 2 Lower limb

PURPOSE

This review discusses the relevant anatomy, etiopathogenesis, current notions in clinical and imaging features as well as management outline of lower limb entrapment neuropathies.

METHODS

The review is based on critical analysis of the current literature as well as our experience in dealing with entrapment neuropathies of the lower limb.

RESULTS

The complex anatomical network of nerves supplying the lower extremities are prone to entrapment by a heterogenous group of etiologies. This leads to diverse clinical manifestations making them difficult to diagnose with traditional methods such as clinical examination and electrodiagnostic studies. Moreover, some of these may mimic other common conditions such as disc pain or fibromyalgia leading to delay in diagnosis and increasing morbidity. Addition of imaging improves the diagnostic accuracy and also help in correct treatment of these entities. Magnetic resonance imaging is very useful for deeply situated nerves in pelvis and thigh while ultrasound is well validated for superficial entrapment neuropathies.

CONCLUSION

The rapidly changing concepts in these conditions accompanied by the advances in imaging has made it essential for a clinical radiologist to be well-informed with the current best practices.

Extra-Articular Impingement at the Anterior Inferior Iliac Spine: A Cause of Refractory Periarticular Pain After Total Hip Arthroplasty

Background

Periarticular pain after total hip arthroplasty (THA) can significantly impair the postoperative functionality. Extra-articular impingement between the greater trochanter and the anterior inferior iliac spine is presented as a cause of refractive pain after THA.

Methods

Twenty patients were treated for refractive periarticular pain and limited internal rotation between January 2014 and April 2016. All patients underwent a positive chair rise test, pelvic inclination test, and Marcainisation test. Patients were treated with bone resection of the anterior part of the greater trochanter with or without component revision.

Results

At a mean follow-up of 20 months, all functional outcomes had improved significantly. All patients were willing to undergo the surgery again. Sixteen (80%) indicated the result as very good, 3 (15%) as good, and one (5%) as poor. Two patients developed a postoperative heterotopic ossification that required resection.

Conclusions

Extra-articular impingement should be considered as a possible cause of refractive groin pain after THA. Bony resection through the Hueter interval provides immediate pain relief with improved functional outcomes 1 year after surgery.

Deep gluteal syndrome as a cause of posterior hip pain and sciatica-like pain

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis. After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy. Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve. Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment. Cite this article: Bone Joint J 2020;102-B(5):556-567.

Anatomical variation of the Psoas Valley: a scoping review

Background

This scoping review aimed to investigate the literature on the anatomy of the psoas valley, an anterior depression on the acetabular rim, and propose a unified definition of the anatomical structure, describe its dimensions, anatomical variations and clinical implications.

Methods

A systematic computer search of EMBASE, PubMed and Cochrane for literature related to the psoas valley was undertaken using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Clinical outcome studies, prospective/retrospective case series, case reports and review articles that described the psoas valley and its synonyms were included. Studies on animals as well as book chapters were excluded.

Results

Of the 313 articles, the filtered literature search identified 14 papers describing the psoas valley and its synonyms such as iliopsoas notch, a notch between anterior inferior iliac spine and the iliopubic eminence, Psoas-U and anterior wall depression. Most of these were cross-sectional studies that mainly analyzed normal skeletal hips. In terms of anatomical variation, 4 different configurations of the anterior acetabular rim have been identified and it was found that the curved type was the most frequent while the straight type may be nonexistent. Additionally, the psoas valley tended to be deeper in males as compared with females. Several papers established the psoas valley, or Psoas-U in a consistent location at approximately 3 o’clock on the acetabular rim which may have implications with labral pathology.

Conclusion

This review highlights the importance of the anatomy of the psoas valley which is a consistent bony landmark. The anatomy and the anatomical variations of the psoas valley need to be well-appreciated by surgeons involved in the management of young adults with hip pathology and also joint replacement surgeons to ensure appropriate seating of the acetabular component.

Prediction of intra-articular pathology and arthroscopic outcomes for femoroacetabular impingement and labral tear based on the response to preoperative anaesthetic hip joint injections

OBJECTIVE

This study investigated whether the preoperative response to intra-articular injections is associated with intra-articular pathological findings and arthroscopy outcomes.

METHODS

This study included 49 patients who underwent arthroscopic hip surgery for femoroacetabular impingement and labral tear after receiving preoperative hip joint injections. The response to anaesthetic injections was categorized as poor (0-50%) or good (51-100%). With respect to anatomical indices, we evaluated the lateral centre-edge angle (LCEA), acetabular roof obliquity (ARO), vertical-centre-anterior angle (VCA), and the alpha angle (on a lateral view). We evaluated the association between these indices (including the types of hip labral tears and cartilage damage) and the effectiveness of intra-articular injections.

RESULTS

The study included 22 men and 27 women, and the mean age of patients was 36.4 years. No statistically significant association was observed between the response to preoperative anaesthetic hip joint injections and patient demographics (age, sex) and anatomical indices (LCEA, ARO, VCA, and alpha angle) (p > 0.05). All patients showed labral damage; however, labral tear classification or cartilage damage was not significantly associated with the effectiveness of joint injections. At the 1-year post-operative follow-up, patients with a good response to anaesthetic hip joint injections showed a significantly better outcome than patients with a poor response to these injections (p < 0.01).

CONCLUSION

The response to preoperative anaesthetic hip joint injections may indicate the presence of intra-articular pathology. Furthermore, this association may have predictive value in determining post-operative outcomes following hip arthroscopy.

Treatment strategies for ischiofemoral impingement: a systematic review

PURPOSE

There has been relatively little information about the treatment for ischiofemoral impingement (IFI) because of its rarity as well as the uncertainty of diagnosis. The aim of this study was to provide the reader with the available treatment strategies and their related outcomes for IFI based on the best available evidence, whilst highlighting classically accepted ways of treatment as well as relatively new surgical and non-surgical techniques.

METHODS

A systematic review of the literature from Medline, Embase, AMED, Cochrane and Google Scholar was undertaken since inception to December 2017 following the PRISMA guidelines. Clinical outcome studies, prospective/retrospective case series and case reports that described the treatment outcome for IFI were included. Animal or cadaveric studies, trial protocols, diagnostic studies without any description of treatments, technical notes without any results, and review articles were excluded.

RESULTS

This systematic review found 17 relevant papers. No comparative studies were included in the final records for qualitative assessment, which means all the studies were case series and case reports. Eight studies (47.1%) utilised non-surgical treatment including injection and prolotherapy, followed by endoscopic surgery (5 studies, 29.4%) then open surgery (4 studies, 23.5%). Mean age of the participants was 41 years (11-72 years). The mean follow-up was 8.4 months distributed from 2 weeks to 2.3 years. No complications or adverse effects were found from the systematic review.

CONCLUSION

Several treatment strategies have been reported for IFI, and most of them have good short- to medium-term outcomes with a low rate of complications. However, there are no comparative studies to assess the superiority of one technique over another, thus further research with randomised controlled trials is required in this arena. This study explores the wide variety and categories of different treatments used for IFI to guide physicians and shed light on what can be done for this challenging cohort of patients.

LEVEL OF EVIDENCE

III.

non-arthroplasty iliopsoas impingement in athletes: a narrative literature review

INTRODUCTION

Iliopsoas impingement occurs secondary to a tight iliopsoas tendon that causes impingement during movement. This review presents current aspects regarding the diagnosis of iliopsoas impingement and also exposes the readers to the possible anatomic and clinical variations together with the available treatment options.

METHODS

We conducted a narrative literature review with regard to non-arthroplasty iliopsoas impingement.

RESULTS

Iliopsoas impingement is characterised by a distinct pattern of labral pathology, with anteriorly localised labral damage, that does not extend to the anterosuperior portion of the acetabulum. Anterior groin pain and intermittent catching, snapping or popping of the hip are common symptoms. Non-specific focal tenderness is often found over the iliopsoas tendon at the level of the anterior aspect of the joint. The 'C-sign' and Impingment test are usually positive. Dynamic ultrasonography is also useful for confirming the diagnosis. Initial management of painful iliopsoas impingement should be conservative. When patients continue to have pain, an ultrasound-guided injection can provide relief and predict the response to the surgical release. For patients who have recurrent pain after local injection of steroids, arthroscopic release has shown to achieve effective results.

CONCLUSIONS

Although different treatment options for iliopsoas impingement are emerging, the current standard of therapy is conservative followed by an arthroscopic tenotomy if necessary. Young adult hip surgeons should always keep this differential in mind in a patient presenting with groin pain and mechanical symptoms.

Evaluation of the ischiofemoral space: a case-control study

Objective

To determine the size of the ischiofemoral space (IFS) and quadratus femoris space (QFS) in patients with and without ischiofemoral impingement (IFI).

Materials and Methods

Case-control study including consecutive patients submitted to magnetic resonance imaging (MRI) of the hip joint during a three-month period. Patients with deep gluteal pain who tested positive for IFI on at least one clinical test and showed signal changes in the quadratus femoris muscle on MRI were categorized as having a confirmed diagnosis of IFI.

Results

Final sample comprised 50 patients submitted to unilateral MRI of the hip joint. The mean age was 47.3 ± 14.0 years (range, 22-76 years), and 33 (66%) of the patients were women. A diagnosis of IFI was made in 6 patients (12%), all of whom were female. On average, IFS and QFS were significantly smaller in IFI group than in control group (11.1 ± 2.7 mm versus 27.5 ± 6.5 mm and 5.3 ± 1.8 mm versus 18.8 ± 4.8 mm, respectively; p < 0.001 for both).

Conclusion

Results of specific clinical tests and MRI findings indicate that the IFS and QFS are significantly reduced in patients with IFI.

ISHA-Richard Villar Best Clinical Paper Award: Acetabular labral tears in sexually active women: an evaluation of patient satisfaction following hip arthroscopy

The aim of this study was to evaluate the effect of symptomatic labral tears on the sex lives of women and the effect of surgical intervention on hip symptoms during sexual intercourse. One hundred and twenty consecutive women who had undergone hip arthroscopy under a single surgeon at a tertiary referral centre were identified. A specific questionnaire was designed and sent to each of the patients. Data were collected on the nature of symptoms, if they experienced any hip pain during sexual intercourse and if this had impacted on their sex lives and the degree of resolution of hip symptoms after the procedure, on a scale of 1-10. One hundred and four responses were available. Ninety-two women reported that they were sexually active. Of these, 87 (94%) reported pain during intercourse affecting their sex life. Eight women reported hip pain for a few days following intercourse and four stated that they are often not able to continue on account of the pain. Mean patient satisfaction with a resolution of symptoms during intercourse was 7.8 out of the 10. Seventy-seven women reported a post-operative improvement in the hip symptoms experienced during sex. Labral tears do have a significant effect on the sex life of women. Hip arthroscopy to address the labral tear as well as any underlying pathology relieves the pain experienced by women during intercourse with, a resultant improvement in their sex lives.

The accuracy assessment of ultrasound for the diagnosis of ischiofemoral space - A Validation Study

OBJECTIVE

To investigate and evaluate the accuracy of ultrasound (US) imaging for measurement of ischiofemoral space (IFS) compared with magnetic resonance imaging (MRI).

METHODS

Twenty-five hips of 16 patients with hip pain and ipsilateral quadratus femoris muscle (QFM) edema were recruited to the IFI group, and 19 hips of 19 patients without hip pain and QFM edema were recruited as the control group. IFS of both groups was measured by US and MRI. The correlations and differences between US and MRI measurements were then assessed. Last, the receiver operating characteristic (ROC) data analysis was performed.

RESULTS

The US results revealed a decreased IFS in IFI hips compared with controls (P < 0.001), suggesting that US were valuable in identifying IFI. IFS measured by US and MRI showed positive correlations in both the IFI group (r = 0.409, P = 0.042) and control group (r = 0.575, P = 0.01). There were no statistically significant differences between IFS measured by US and MRI in the control group (P = 0.657), while IFS measurements in the IFI group performed with US were significantly greater than those with MRI (P < 0.001). ROC curve analysis revealed that the cutoff value of IFS measured with US was 2.14 cm, with a sensitivity of 92.0% and specificity of 68.4%, while measured by MRI was 1.87 cm, with a sensitivity of 96.0% and specificity of 84.2%.

CONCLUSIONS

IFS measurements obtained with US are very similar to those obtained with MRI. Therefore, US provides a low-cost and easy-to-operate alternative imaging modality to measure IFS.

Arthroscopic excision of heterotopic ossification in the rectus femoris muscle causing extra-articular anterior hip impingement

Subspine impingement is an extra-articular hip impingement syndrome that usually occurs when there is abnormal contact between an enlarged or malorientated anterior inferior iliac spine (AIIS) and the distal anterior femoral neck in straight flexion of the hip. We present the case of a 13-year-old boy with a history of left groin pain and loss of range of movement of the hip for over six months following an avulsion fracture of the AIIS during a game of rugby. He was diagnosed with subspine impingement secondary to a large lesion of heterotopic ossification in the rectus femoris; this was dissected and extracted from the muscle in toto arthroscopically. This case highlights the importance of heterotopic ossification after injury as an important cause for subspine impingement in the young adult hip. This is the first report and describes subspine impingement secondary to a large lesion of heterotopic ossification.

[Arthroscopic decompression of extra-articular subspinal hip impingement]

OBJECTIVE

Complete arthroscopic decompression of the impinging subspinal soft tissues and resection of the hypertrophic bone formation between the anterior hip capsule and the anterior inferior iliac spine (AIIS) or decompression of a hypertrophic AIIS.

INDICATIONS

Painful anterior hip impingement and decreased hip flexion following a hypertrophic osseous subspinal deformation.

CONTRAINDICATIONS

No clinical symptoms or decreased anterior hip function despite radiological osseous subspinal hip impingement.

SURGICAL TECHNIQUE

Hip arthroscopy in supine position on an extension table. Treatment of possible intraarticular hip pathologies in the central or peripheral compartment. Arthroscopic visualization of the hypertrophic impinging soft tissues below the AIIS and decompression using a shaver or radiofrequency device. Complete arthroscopic resection of the hypertrophic AIIS parts and the osseous subspinal deformation using a high speed burr under fluoroscopic control.

POSTOPERATIVE MANAGEMENT

Early functional rehabilitation with full weight-bearing and unlimited hip motion; 3 weeks ossification prophylaxis and 8 weeks of limitation for jumping and running sports activities.

RESULTS

There are no comparative studies or medium- and long-term study results in the literature for arthroscopic AIIS decompression. However, currently published case series show an improvement of the determined scores.

Complications following arthroscopic surgery of the hip: a systematic review of 36 761 cases

AIMS

The number of patients undergoing arthroscopic surgery of the hip has increased significantly during the past decade. It has now become an established technique for the treatment of many intra- and extra-articular conditions affecting the hip. However, it has a steep learning curve and is not without the risk of complications. The purpose of this systematic review was to determine the prevalence of complications during and following this procedure.

MATERIALS AND METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in designing this study. Two reviewers systematically searched the literature for complications related to arthroscopy of the hip. The research question and eligibility criteria were established a priori. Pertinent data were abstracted and analysed.

RESULTS

We found 276 relevant studies with a total of 36 761 arthroscopies that met the inclusion criteria. The mean age of the patients was 36.7 years (1.7 to 70) and the mean body mass index was 25.7 kg/m² (20.2 to 29.2). Femoroacetabular impingement and labral tears were the most common indications for the procedure. The total number of complications was 1222 (3.3%). Nerve injury (0.9%), mainly involving the pudendal and lateral femoral cutaneous nerves, and iatrogenic chondral and labral injury (0.7%), were the two most common complications. There were 58 major complications (0.2%), the most common being intra-abdominal extravasation of fluid, which was found in 13 cases (0.04%). There were three deaths (0.008%).

CONCLUSION

Arthroscopic surgery of the hip is a procedure with a relatively low rate of complications, although some may be significant in this young cohort of patients. This study relied on the reported complications only and the results should be interpreted with caution. Cite this article: Bone Joint J 2017;99-B:1577-83.

Arthroscopic Decompression of Greater Trochanteric Sciatic Nerve Impingement

Therapeutic extra-articular hip endoscopy is an effective treatment of greater trochanteric sciatic nerve impingement. We describe in detail technical pearls of the procedure including positioning, portal placement, and steps to obtaining adequate decompression while avoiding iatrogenic nerve injury.