Preoperative factors associated with 180°, 270°, and 360° labral tears

BACKGROUND

Large, circumferential glenoid labral tears are an uncommon injury affecting young, athletic patients. There are limited data describing the clinical presentation of patients with larger tears, especially 270° and 360° labral tears. Additionally, examination and imaging findings have poor reliability in diagnosing these tears. The purpose of this study was to determine the clinical presentation among patients presenting with small (less than 180°), medium (180°-270°), and large (270°-360°) labral tears.

METHODS

This is a retrospective comparative study of consecutive patients surgically managed by a single shoulder surgeon for all glenoid labral tears from 2018-2022. The primary outcome was demographic and preoperative clinical risk factors. Demographic data including age, sex, hand dominance, body mass index, as well as clinical presentation (subluxation vs. dislocation, instability history, and participation in contact sports) were recorded.

RESULTS

A total of 188 patients met the inclusion criteria: 101 of 188 (53.70%) patients with small tears, 43 of 188 (22.90%) patients with medium tears, and 44 of 188 (23.40%) patients with large tears. Individuals with large and medium-sized labral tears were more likely to have participated in contact sports compared to those with smaller labral tears (P = .003). Medium and smaller tears were more likely to present as dominant-side injury (P = .02). Furthermore, medium and large tears were more likely to present with anterior instability symptoms compared with smaller tears, which more frequently presented with posterior instability and pain (P = .003).

CONCLUSION

Males participating in contact sports were the most common demographic population presenting with large, 270°-360° labral tears. Instability was the primary complaint rather than pain, and compared with small tears, medium and large tears were more likely to present with primary anterior instability. Although arthroscopic repair of 270°-360° labral tears can yield excellent clinical outcomes similar to smaller tears, identifying factors associated with larger glenoid labral tears may help in surgical planning and patient counseling.

SSR white paper: guidelines for utilization and performance of direct MR arthrography

OBJECTIVE

Direct magnetic resonance arthrography (dMRA) is often considered the most accurate imaging modality for the evaluation of intra-articular structures, but utilization and performance vary widely without consensus. The purpose of this white paper is to develop consensus recommendations on behalf of the Society of Skeletal Radiology (SSR) based on published literature and expert opinion.

MATERIALS AND METHODS

The Standards and Guidelines Committee of the SSR identified guidelines for utilization and performance of dMRA as an important topic for study and invited all SSR members with expertise and interest to volunteer for the white paper panel. This panel was tasked with determining an outline, reviewing the relevant literature, preparing a written document summarizing the issues and controversies, and providing recommendations.

RESULTS

Twelve SSR members with expertise in dMRA formed the ad hoc white paper authorship committee. The published literature on dMRA was reviewed and summarized, focusing on clinical indications, technical considerations, safety, imaging protocols, complications, controversies, and gaps in knowledge. Recommendations for the utilization and performance of dMRA in the shoulder, elbow, wrist, hip, knee, and ankle/foot regions were developed in group consensus.

CONCLUSION

Although direct MR arthrography has been previously used for a wide variety of clinical indications, the authorship panel recommends more selective application of this minimally invasive procedure. At present, direct MR arthrography remains an important procedure in the armamentarium of the musculoskeletal radiologist and is especially valuable when conventional MRI is indeterminant or results are discrepant with clinical evaluation.

Acromioclavicular joint dislocation and concomitant labral lesions: a systematic review

Acromioclavicular (AC) joint dislocations frequently co-occur with intra-articular glenohumeral pathologies. Few comprehensive studies have focused on labral tears specifically associated with AC joint trauma. This systematic review will address this gap. A comprehensive electronic search was conducted across PubMed, Cochrane Library, and Google Scholar (pages 1-20) spanning from 1976 to May 19, 2023. Seven studies met the inclusion criteria for this systematic review, consisting of three retrospective studies and four case series. These studies collectively involved 1,044 patients, of whom 282 had concomitant labral lesions. The pooled prevalence of intra-articular labral injuries associated with acute AC joint dislocation was 27%. The prevalence of these labral lesions varied significantly between studies, ranging from 13.9% to 84.0% of patients, depending on the study and the grade of AC joint dislocation. Various types of labral tears were reported, with superior labrum anterior to posterior (SLAP) lesions being the most common. The prevalence of SLAP lesions ranged from 7.2% to 77.4%, with higher grades of AC joint dislocations often associated with a higher prevalence of SLAP tears. Moreover, grade V dislocations exhibited a complete correlation with SLAP tears. The studies yielded contradictory findings regarding older age and higher grades of AC joint dislocation as risk factors for concurrent labral lesions. This review underscores the frequent association between labral lesions and AC joint dislocations, particularly in cases of lower-grade injuries. Notably, SLAP lesions emerged as the predominant type of labral tear.

Are degenerative findings detected on traction MR arthrography of the hip associated with failure of arthroscopic femoroacetabular impingement surgery?

OBJECTIVES

To identify preoperative degenerative features on traction MR arthrography associated with failure after arthroscopic femoroacetabular impingement (FAI) surgery.

METHODS

Retrospective study including 102 patients (107 hips) undergoing traction magnetic resonance arthrography (MRA) of the hip at 1.5 T and subsequent hip arthroscopic FAI surgery performed (01/2016 to 02/2020) with complete follow-up. Clinical outcomes were assessed using the International Hip Outcome Tool (iHOT-12) score. Clinical endpoint for failure was defined as an iHOT-12 of < 60 points or conversion to total hip arthroplasty. MR images were assessed by two radiologists for presence of 9 degenerative lesions including osseous, chondrolabral/ligamentum teres lesions. Uni- and multivariate Cox regression analysis was performed to assess the association between MRI findings and failure of FAI surgery.

RESULTS

Of the 107 hips, 27 hips (25%) met at least one endpoint at a mean 3.7 ± 0.9 years follow-up. Osteophytic changes of femur or acetabulum (hazard ratio [HR] 2.5-5.0), acetabular cysts (HR 3.4) and extensive cartilage (HR 5.1) and labral damage (HR 5.5) > 2 h on the clockface were univariate risk factors (all p < 0.05) for failure. Three risk factors for failure were identified in multivariate analysis: Acetabular cartilage damage > 2 h on the clockface (HR 3.2, p = 0.01), central femoral osteophyte (HR 3.1, p = 0.02), and femoral cartilage damage with ligamentum teres damage (HR 3.0, p = 0.04).

CONCLUSION

Joint damage detected by preoperative traction MRA is associated with failure 4 years following arthroscopic FAI surgery and yields promise in preoperative risk stratification.

CLINICAL RELEVANCE STATEMENT

Evaluation of negative predictors on preoperative traction MR arthrography holds the potential to improve risk stratification based on the already present joint degeneration ahead of FAI surgery.

KEY POINTS

• Osteophytes, acetabular cysts, and extensive chondrolabral damage are risk factors for failure of FAI surgery. • Extensive acetabular cartilage damage, central femoral osteophytes, and combined femoral cartilage and ligamentum teres damage represent independent negative predictors. • Survival rates following hip arthroscopy progressively decrease with increasing prevalence of these three degenerative findings.

Trilobite hypostome as a fusion of anterior sclerite and labrum

The trilobite hypostome is a biomineralized ventral plate that covers the mouth, but its evolutionary origin remains controversial. The labrum is a lobe-like structure that can take on variety of shapes in front of the mouth in arthropods, while the anterior sclerite refers to a cuticular plate articulated to the anterior margin of the head in some Cambrian arthropods. Here I present a perspective that views the trilobite hypostome as a fusion of the anterior sclerite and the labrum based on anatomical, topological, and developmental evidence. According to this perspective, the anterior lobe of the hypostome originated from the anterior sclerite, while the posterior lobe reflects a remnant of the sclerotized cover of the labrum. The convex anterior lobe housed the root of the eye stalks, represented by the palpebral ridges and the hypostomal wing, and the posterior lobe occasionally developed a pair of posterolateral extensions, as do the labra. The position of the antennal insertion was located in front of the posterior lobe, displaying a similar topology to the Cambrian arthropods with the labrum. The hypostome was present in many artiopodans except for the Conciliterga, in which the anterior sclerite was separate from the labrum.

Anterior Shoulder Instability and Open Procedures: History, Indications, and Clinical Outcomes

The shoulder, being the most mobile joint in the human body, is often susceptible to dislocations and subluxations more so than other joints. As such, shoulder instability constitutes a common complaint among patients worldwide, especially those who are young, participate in contact sports, and have increased innate flexibility in their joints. Management options in the setting of instability vary between conservative and surgical options that aim to mitigate symptoms and allow return of function. Surgical options can be arthroscopic and open, with a general shift among surgeons towards utilizing arthroscopic surgery in the past several decades. Nevertheless, open procedures still play a role in managing shoulder instability patients, especially those with significant bone loss, recurrent instability, coexisting shoulder pathologies, and high risk of failure with arthroscopic surgery. In these clinical settings, open procedures, like the Latarjet procedure, open Bankart repair, glenoid bone augmentation using iliac crest autograft or distal tibial allograft, and salvage options like glenohumeral arthrodesis and arthroplasty may show good clinical outcomes and low recurrence rates. Each of these open procedures possesses its own set of advantages and disadvantages and entails a specific set of indications based on published literature. It is important to cater treatment options to the individual patient in order to optimize outcomes and reduce the risk of complications. Future research on open shoulder stabilization procedures should focus on the long-term outcomes of recently utilized procedures, investigate different graft options for procedures involving bone augmentation, and conduct additional comparative analyses in order to establish concrete surgical management guidelines.

Anatomic risk factors for arthroscopic Bankart repair failure: A case-control study comparing failure and non-failure groups in an Asian population

Introduction

Post-arthroscopic Bankart repair failure/re-dislocation rates are influenced by several risk factors, including anatomic defects. There is limited evidence on the role of anatomic defects, especially for Hill-Sachs size in on-track lesions. This study aimed to assess glenoid bone loss, Hill-Sachs lesion and labral tear size and evaluate their contribution to post-operative instability after a primary repair.

Material and methods

Across 169 patients with on-track Bankart lesions who underwent primary arthroscopic Bankart repair from 2010 to 2015, this study matched 14 failure with 14 non-failure cases based on age/gender. Patient demographics, pre-operative radiological parameters (including size of glenoid bone loss and Hill-Sachs lesion) and labral tear size were compared between the failure and non-failure groups.

Result

All patients were male with a mean age of 21.01 ± 4.97. Significantly greater glenoid bone loss (p = 0.024) and labral tear size (p = 0.039) were found in the failure group. However, there was no significant difference in mean volume of Hill-Sachs lesion between the two groups (p = 0.739).

Conclusion

Extensive glenoid bone loss and labral tears are risk factors for post-arthroscopic Bankart failure. However, the size of Hill-Sachs lesion is not a risk factor for failure, in a specific group of on-track Hill-Sachs lesions.

Level of evidence

Retrospective Study, Level IV.

Hip Labral Morphological Changes in Patients with Femoroacetabular Impingement Speed Up the Onset of Early Osteoarthritis

Over the last decade, evidence has mounted for a prominent etiologic role of femoroacetabular impingement (FAI) in the development of early hip osteoarthritis (OA). The aim of this study was to compare the ultrastructure and tissue composition of the hip labrum in healthy and pathological conditions, as FAI and OA, to provide understanding of structural changes which might be helpful in the future to design targeted therapies and improve treatment indications. We analyzed labral tissue samples from five healthy multi-organ donors (MCDs) (median age, 38 years), five FAI patients (median age, 37 years) and five late-stage OA patients undergoing total hip replacement (median age, 56 years). We evaluated morpho-functional by histology and transmission electron microscopy. Extracellular matrix (ECM) structure changes were similar in specimens from FAI compared to those from patients with OA (more severe in the latter) showing disorganization of collagen fibers and increased proteoglycan content. In FAI and in OA nuclei the chromatin was condensed, organelle degenerated and cytoplasm vacuolized. Areas of calcification were mainly observed in FAI and OA labrum, as well as apoptotic-like features. We showed that labral tissue of patients with FAI had similar pathological alterations of tissue obtained from OA patients, suggesting that FAI patients might have high susceptibility to develop OA.

Arthroscopic Bankart repair: how many knotless anchors do we need for anatomic reconstruction of the shoulder?-a prospective randomized controlled study

PURPOSE

The optimal strategy for surgical repair of traumatic anterior shoulder instability remains controversial. While several study groups have reported that the clinical and radiological outcomes of arthroscopic procedures performed with two anchors are not fully adequate, these conclusions are not supported by the findings published in other studies. A prospective randomized study was conducted to compare the structural and clinical outcomes of surgical procedures involving two vs. three anchors.

METHODS

Patients who underwent arthroscopic Bankart repair were randomly assigned to either Group I, which underwent procedures involving two double-loaded 3.5-mm knotless anchors, or Group II, which underwent procedures involving three single-loaded 2.9-mm knotless anchors. All patients underwent bilateral MRI assessments at a minimum of 12 months and clinical assessment at a minimum of 24 months postoperatively. To evaluate the reconstruction of the labral capsular ligamentous complex (LCLC), the labrum-glenoid height index (LGHI), restored labral height (LH), and labral slope (LS) were measured for both shoulders. For clinical assessment, the redislocation rate and functional outcome scores (Constant score (CS), American Shoulder and Elbow Surgeon score (ASES), Walch Duplay score (WDS), and Rowe score (RS)) were evaluated at follow-up visits.

RESULTS

Bankart repair with two knotless anchors showed lower values for anterior reconstruction of the LCLC compared to the uninjured contralateral shoulder. Likewise, significant differences were noted when comparing these measurements to those from patients who underwent reconstruction with three anchors. No differences were demonstrated with regard to the reconstruction of the inferior LCLC. Clinical assessment showed good to excellent results in both groups. In total, three patients experienced redislocation of the shoulder: two in group I and one in group II. No significant differences were found with respect to clinical outcomes and redislocation rates.

CONCLUSION

Bankart repair with both two and three knotless anchors results in effective anatomical reconstruction of the labral capsular ligamentous complex. Although the two-anchor technique yields significantly lower values for the anterior portion compared with the contralateral side, none of these differences reach clinical relevance as per our original definition.

MRI assessment of femoral head docking following closed reduction of developmental dysplasia of the hip

AIMS

Eccentric reductions may become concentric through femoral head 'docking' (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI.

METHODS

We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.

RESULTS

At the end of the first cast period, 73 hips (79.3%) had a FTD < 1 mm. Multiple regression analysis showed that FTD (p = 0.011) and immobilization duration (p = 0.028) were associated with complete reduction. At the end of the second cast period, all 92 hips achieved complete reduction. The LACC on initial MRI was inverted in 69 hips (75.0%), partly inverted in 16 hips (17.4%), and everted in seven hips (7.6%). The LACC became everted-congruent in 45 hips (48.9%) and 92 hips (100%) at the end of the first and second cast period, respectively. However, a residual inverted labrum was present in 50/85 hips (58.8%) with an initial inverted or partly inverted LACC.

CONCLUSION

An eccentric reduction can become concentric after complete reduction and LACC remodelling following CR for DDH. Varying immobilization durations were required for achieving complete reduction. A residual inverted labrum was present in more than half of all hips after LACC remodelling.Cite this article: Bone Joint J 2023;105-B(2):140-147.

Update on contribution of hip labral tears to hip pain: A narrative review

Hip labral tears are found in 22-55% of individuals with hip pain, but labral tears without cysts are usually not responsible for hip pain, which originates mostly from other structures than the torn labrum, like osteochondral, but also tendinous injuries (rectus femoris, gluteus minimus, iliopsoas) or capsulo-ligamentous tears (iliofemoral ligaments, ligament teres). Those lesions are mainly the consequences of underlying unrecognized functional acetabular dysplasia, and/or femoroacetabular impingements. Although the early repair of labral tears in young sportsmen induces a marked and lasting relief, and might delay the onset of osteoarthritis, the microinstability fostered by labral damages seems less important than underlying dysplasias/impingements. This narrative review details recent findings on: (i) the various mechanisms of pain associated with labral tears; (ii) few evidence for hip microinstability induced by isolated labral tears; (iii) how to best detect labral tears, both clinically (including through IROP test) and on imaging (MRI, MRA, computed tomography arthrography, ultrasound). Some authors suggested to use pull-out tests during surgery, but pulling of hips do not seem to increase much diagnostic performances of ultrasounds. Ultrasound-guided intra-articular and peri-articular injections may tell how often hip pain is exclusively induced by peri-capsular injuries secondary to the acetabular dysplasia/femoro-acetabular impingements already responsible for labral tears. Further works could tell whether labral repair, tendinous debridement, plication of capsule, and/or focal denervation, may induce lasting reliefs of pain induced by the chronic contraction of surrounding muscles (rectus femoris, gluteus minimus, psoas), whose deep aponeuroses mix with the superficial fibres of the thick hip capsule.

Effective Management Options for Treatment of Microinstability of the Hip: a Scoping Review

PURPOSE OF REVIEW

To review the recent literature identifying and summarizing the research involving management of microinstability of the hip and highlight new and evolving techniques in its treatment.

RECENT FINDINGS

Recent updates in the understanding of capsular management hip arthroscopy will likely lead to less revision surgery and a decreased incidence of persistent post-operative pain. Repair of residual capsular defects has shown good outcomes with high patient satisfaction. Capsular plication remains the gold standard for hips with increased pain that show signs of capsular laxity/deficiency on exam or imaging. Capsular reconstruction has shown equivalent results to other revision hip arthroscopy procedures with low rates of complications. Ligamentum teres pathology, although rare, should be considered a source of pain, particularly in patients with laxity on exam. In cases where CAM over-resection has occurred, remplissage using allograft is an effective option for restoring the capsular suction seal and stability. Microinstability is increasingly being recognized as a source of post-operative hip pain. Patients with collagen disorders remain a challenging clinical entity with increased rates of complications and post-operative pain. CAM resection should be performed carefully and not disrupt the suction seal but be sufficient to not cause further impingement. Improved evidence including well-designed prospective studies with large sample sizes will determine the future management of this complex problem.

Increased superior translation following multiple simulated anterior dislocations of the shoulder

PURPOSE

Recurrent shoulder dislocations can result in kinematic changes of the glenohumeral joint. The number of prior shoulder dislocations may contribute to increased severity of capsulolabral lesions. The kinematics of the glenohumeral joint following multiple dislocations remain poorly understood. The purpose of this study was to assess the kinematics of the glenohumeral joint during anterior dislocations of the shoulder, and more specifically, altered translational motion following multiple dislocations. The kinematics of the glenohumeral joint were hypothesized to change and correlate with the number of dislocations.

METHODS

Eight fresh-frozen cadaveric shoulders were dissected free of all soft tissues except the glenohumeral capsule. Each joint was mounted in a robotic testing system. At 60 degrees of glenohumeral abduction, an internal and external rotational torque (1.1 Nm) were applied to the humerus, and the resulting joint kinematics were recorded. Anterior forces were applied to the humerus to anteriorly dislocate the shoulder and the resulting kinematics were recorded during each dislocation. Following each dislocation, the same rotational torque was applied to the humerus, and the resulting joint kinematics were also recorded. A repeated-measures analysis of variance (ANOVA) was used to compare the kinematics following each dislocation.

RESULTS

During the 7th, 8th, 9th, and 10th dislocations, the humerus significantly translated superiorly compared with the shoulder during the 1st dislocation (p < 0.05). Following the 3rd, 4th, 5th, and 10th dislocations, the humeral head significantly translated superiorly compared with the shoulder following the 1st dislocation in the position of 60 degrees of abduction in response to external rotation torque (p < 0.05).

CONCLUSION

Multiple anterior shoulder dislocations lead to abnormal translational kinematics and result in increased superior translation of the humerus. This may contribute to pathologic superior extension of capsulolabral injuries. Superior translation of the humerus with overhead motion in the setting of recurrent instability may also place the shoulder at risk for extension of the capsulolabral injuries.

Intra-articular Soft Tissue Pathology of the Postpartum Hip: A Systematic Review

PURPOSE OF REVIEW

Pregnancy-related lumbopelvic and hip pain affects over half of postpartum females and has multiple aetiologies. The relative contribution of intra-articular soft tissue pathology to pregnancy-related hip pain is unknown. The current review investigates the available evidence regarding underlying intra-articular soft tissue aetiologies of hip pain in females during pregnancy and in the acute postpartum period.

RECENT FINDINGS

Three online databases (Embase, PubMed and Ovid [MEDLINE]) were searched from database inception until 11 April 2021. All titles, relevant abstracts and full-text articles were screened by two reviewers independently. The methodological quality of the included studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS) instrument. Descriptive study characteristics are presented in a narrative summary. Five level IV evidence articles were eligible for inclusion. Twenty-two females were included. Twenty patients presented with labral pathology, 15 of which necessitated hip arthroscopy with labral debridement or repair with or without acetabuloplasty and/or femoroplasty. One patient presented with an incidental labral tear in the context of osteitis condensans illi. One patient presented with posttraumatic osteoarthritis necessitating a hip arthroplasty. The contribution of intra-articular soft tissue injury is a documented, albeit sparse, aetiology contributing to pregnancy-related hip pain. Further research to better delineate the prevalence, natural history and optimal management options for females who sustained these injuries at a life-altering juncture is necessary to advance the care of these patients.

The O'Brien test demonstrates a higher diagnostic value in identifying posteroinferior labral tears than superior labral anterior to posterior (SLAP) tears

Background

The primary aim was to determine the diagnostic value of the O'Brien test in localizing labral tears of the shoulder.

Methods

A consecutive series of patients electing for labral repair between January 2005 and March 2021 were included in this retrospective study. Inclusion criteria were as follows: (1) any patient with a labral tear who was elected for arthroscopic labral repair and (2) had documentation of the O'Brien test in the preoperative evaluation. Exclusion criteria were patients that had a negative arthrographically enhanced computed tomography or magnetic resonance imaging scan. During arthroscopy, the localization and extension of the labral tear was documented in a standardized 12-o'clock configuration. Anteroinferior, posteroinferior, superior labrum anterior to posterior (SLAP), and combined labral tears were documented. The sensitivity, specificity, positive and negative predictive values, accuracy, positive and negative likelihood ratios, receiver operating characteristic curve, and area under the curve were calculated to determine the diagnostic value.

Results

The cohort consisted of 271 patients (77% male) and included 105 anteroinferior, 86 posteroinferior, 46 SLAP, and 32 combined parts of the labrum. The mean age at time of surgery was 30 (±10.2) years. The O'Brien test was positive in 142 (52%) patients and showed the highest sensitivity and specificity for the posteroinferior tears (83% and 62%) compared to the anteroinferior (16% and 25%), combined labral parts (69% and 50%), and SLAP (65% and 50%) tears. In addition, receiver operating characteristic-analysis demonstrated a significantly higher area under the curve for posteroinferior tears compared to the other tears (P < .001).

Conclusion

The O'Brien test demonstrates more diagnostic value for posteroinferior tears than other labral tears. This includes the SLAP tear, for which the O'Brien test was originally designed.

Clinical Relevance

These findings are helpful towards reinterpreting the O'Brien test as well as diagnosing, and more specifically localizing labral tears in clinics.

Diagnostic performance of MRA in abduction and external rotation position in the detection of glenoid labral lesions: a systematic review and meta-analysis

OBJECTIVE

To compare the diagnostic performance of direct magnetic resonance arthrography (MRA) for labral lesions during conventional, abduction and external rotation (ABER), conventional plus abduction, and external rotation (ABER) positioning by using a systematic review and meta-analysis.

MATERIALS AND METHODS

A comprehensive literature search was performed on the two main concepts of magnetic resonance arthrography: extremity position and labral lesions. Inclusion criteria consisted of original studies that assessed the diagnostic accuracy of MR arthrography in ABER and conventional position alone or combined for the diagnosis of labral lesions by using surgical findings as the reference standard. Meta-analyses were performed that compared MR arthrography during conventional positioning, ABER, and conventional plus ABER positioning.

RESULTS

Nine studies met the inclusion and exclusion criteria. A total of 733, 504, and 313 lesions assessed by conventional MRA, ABER MRA, and conventional plus ABER MRA, respectively, were included in our analysis. Pooled sensitivities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 81.5%, 81.6%, and 95.7%, respectively. Pooled specificities of MRA in conventional, ABER, and conventional plus ABER position for labral tear diagnosis were 88.8%, 85.6%, and 94.5%, respectively. Summary receiver operator characteristic (ROC) curve demonstrated improved accuracy of conventional plus ABER MRA compared with conventional MRA or ABER MRA with the area under the curve (AUC) of 0.99, 0.90, and 0.88, respectively.

CONCLUSION

Conventional plus ABER MRA showed increased diagnostic accuracy compared to both ABER MRA and conventional MRA alone in the diagnosis of labral lesions.

Arthroscopic acetabular labrum suture

It is essential to be aware of the anatomy and biomechanics of the acetabular labrum in order to understand why it should be conserved. Vascularization comes from the capsule and also from the bone. The joint side contains numerous nerve endings, which explains why labral lesions are painful. It is involved in joint stabilization by maintaining a negative pressure inside the joint able to resist distraction. It acts as a seal. There are two main suture techniques: trans- and peri-labral. Translabral suture is better suited to a wide and solid labrum free of degenerative lesions. Both techniques should be known, and may be associated. Results are comparable. It is essential to manage the underlying pathology responsible for the labral lesion. Joint degeneration is associated with poor prognosis. It needs to be recognized and discussed with the patient, to avoid unrealistic expectations.

Residual acetabular dysplasia in congenital hip dysplasia

Residual hip dysplasia may exist despite appropriate treatment of congenital hip dysplasia (CHD). The abnormalities chiefly affect the acetabulum and can lead to premature osteoarthritis. Although the main cause is delayed treatment of CHD, primary lesions are also possible and may be worsened by the initial treatment itself. Residual hip dysplasia must be detected during the follow-up of patients with CHD. The antero-posterior radiograph of the pelvis is the main diagnostic tool. However, the importance of non-ossified anatomical structures requires additional investigations such as arthrography and magnetic resonance imaging. The risk of premature osteoarthritis is difficult to predict based only on the imaging-study findings. Hip dysplasia is best treated before 5 years of age. The work-up at this age should allow determination of the best treatment. Surgery is required but should not be performed unnecessarily. The decision rests on the absence of improvement in the radiographic criteria and on the findings from additional imaging studies. The usual treatment is Salter's osteotomy, during which excessive anterior displacement should be avoided. At adolescence, the information provided by radiography in the coronal plane should be completed by a three-dimensional evaluation of the acetabulum and an assessment of the quality of the labrum. The shelf procedure has been proven to relieve pain and to significantly postpone the need for hip arthroplasty, when performed early, before the development of visible osteoarthritis, and on a congruent hip. Chiari's osteotomy has a role to play in complex dysplasia affecting both the acetabulum and the femur. Periacetabular osteotomy is getting more used thanks to cooperation between paediatric and adult orthopaedic surgeons. This osteotomy provides optimal correction in all three dimensions.

Variability of glenoid labral tear patterns: a study of 280 sequential surgical cases

BACKGROUND

Glenoid labrum tears are a common cause of shoulder pain and instability and tear patterns have historically been ascribed into categorical descriptions such as anterior, posterior, and superior labral tears (SLAP [superior labrum anterior and posterior]) with multiple subtypes. Although often quoted as representing no more than 10% of instabilities, posterior shoulder instability may be more common than previously recognized. The purpose of this study was to review observed labral tear patterns and compare incidence and morphologies to historical descriptions.

METHODS

All patients undergoing arthroscopic or open labral repair (Current Procedural Terminology codes 29806, 29807, 23455, 23460, 23462, 23465) by 2 fellowship-trained shoulder surgeons from July 2012 to May 2019 were retrospectively reviewed. Labral tears were categorized into 3 groups: exclusively anterior to the midline of the glenoid, exclusively posterior, and those crossing the midline of the glenoid. Chief complaint, mechanism of injury, hand dominance, preoperative MRI interpretation by surgeon, and independent radiologist were analyzed for each tear type.

RESULTS

During the 7-year period, 280 patients underwent arthroscopic or open labral repair. Sixty percent of tears were traumatic, with dislocation being the most common traumatic mechanism at 31.4%. Ten distinct tear patterns were identified: 3 types of 90° tears (anteroinferior, posteroinferior, and posterosuperior), 4 types of 180° tears (anterior, posterior, inferior, and SLAP), 2 types of 270° tears (anteroinferior and anterosuperior), and 360° labral tears. A total of 134 tears (47.9%) were classified as posterior, and 72 tears (25.7%) were anterior. Seventy-four tears (26.4%) were combined anterior-posterior tears. Labral tears involving some portion of the posterior labrum constituted 74% of tears. A significant association between tear location and primary complaint (P < .001) was noted. Patients with anterior tears complained of only instability in 62.5% of cases, and only pain in 22%. Patients with posterior labral tears complained primarily of pain in 68% of cases, and instability in 21%. There was an accurate preoperative diagnosis given by both radiologists and surgeons on 30% (n = 63) of the tears.

CONCLUSION

There is a wide variety of labral tear patterns identified at the time of surgery, and the incidence of posterior labral tears is higher than previously described. Isolated Bankart lesions are relatively rare and are often associated with more extensive labral lesions. Patients with posterior labral pathology more often complain of pain rather than instability, whereas patients with anterior labral tears more often complain of instability.

Clinical outcomes after arthroscopic treatment of calcification with surrounding inflammation in the hip labrum

PURPOSE

The purpose of this study was to investigate the surgical methods and clinical outcomes of arthroscopic treatment of a special type of calcification with surrounding inflammation in the acetabular labrum of the hip, which was temporarily named "calcifying labrumitis".

METHODS

From April 2015 to November 2019, a total of seven patients with calcifying labrumitis of the hip who underwent arthroscopic excision of calcified lesions and suture or partial resection of the labrum were included in this study. Radiographs were retrospectively evaluated for morphologic characteristics of calcifying labrumitis. Each patient was assessed by the visual analogue scale (VAS), modified Harris hip score (mHHS), nonarthritic hip score (NAHS) and satisfaction rate before surgery and at the final follow-up evaluation.

RESULTS

Seven patients, one male and six females aged 29-48 years, were included in the study; of these patients, three had calcifying labrumitis on the left side and four had calcifying labrumitis on the right side. All patients had hip pain and limited range of motion for a mean of 7.5 ± 3.1 months (range, 3-12 months). The mean follow-up period was 34.9 ± 19.5 months (range, 12-66 months). The lateral central-edge angle (LCEA) was 31.7 ± 3.9° (range, 28.8-36.4°), and the α angle was 41.4 ± 5.3° (range, 33.6-48.2°). None of the patients had cam or pincer lesions. After complete removal of calcified lesions, five patients underwent repair of the labrum with a suture anchor, and two patients underwent partial resection of the labrum. The symptoms of all patients improved significantly at the last follow-up. Mean scores improved from 5.8 ± 1.5 to 1.1 ± 0.3 (p < 0.01) for the VAS, from 57.3 ± 10.6 to 90.8 ± 13.4 for the mHHS and from 62.5 ± 10.7 to 84.3 ± 9.6 for the NAHS. The satisfaction rate was 100%.

CONCLUSION

Calcifying labrumitis of the hip is a special kind of rare disease that is different from calcifications accompanying FAI and os acetabuli. Arthroscopic treatment of calcification with suture or partial resection of the labrum is an effective, safe and minimally invasive method, significantly relieving pain and improving hip joint function.

LEVEL OF EVIDENCE

Level IV.

Proximal femoral epiphyseal spurs and their association with acetabular labral tears on MRI in symptomatic patients

OBJECTIVE

Femoral epiphyseal spurs are developmental projections that form at the edge of the physis. Although considered incidental, their association with acetabular labral tears has never been examined. Our aim was to assess the prevalence of femoral epiphyseal spurs in symptomatic patients with mechanical hip pain and explore if they are associated with labral tears on MRI.

MATERIALS AND METHODS

Hip MRI scans performed on a Siemens 3 T MRI using femoroacetabular impingement protocol were retrospectively reviewed. All patients were referred by orthopaedic surgeons for mechanical hip pain. Two musculoskeletal radiologists blinded to initial reports evaluated MRI images for the presence of an epiphyseal spur and acetabular labral changes. A consensus was achieved on all cases by the two readers. The association between epiphyseal spurs and labral changes was assessed using Fisher's exact test.

RESULTS

A total of 115 patients (178 hip MRI scans) were reviewed; the mean age was 28.8 years (SD 7.1). There were 52 females (45.2%) and 63 males (54.8%). There were 115 hips with labral tears (64.6%). Fourteen hips (7.8%) in ten patients (8.7%) demonstrated epiphyseal spurs and all of them showed labral tears (100%). There was statistically significant association between epiphyseal spurs and labral tears on MRI (p value = 0.0024).

CONCLUSION

Femoral epiphyseal spurs were observed in 8.7% of our defined patient population, and all patients with epiphyseal spurs demonstrated labral tears. Epiphyseal spurs should be documented on imaging reports due to their potential association with labral tears. Future research is needed to further delineate and guide management of these entities.

Intraneural ganglion cyst of the lumbosacral plexus mimicking L5 radiculopathy: A case report

BACKGROUND

Intraneural ganglion cysts are benign gelatinous masses that form within the epineurium of a peripheral nerve. Only few cases of intraneural ganglion cyst arising from the hip joint have been reported.

CASE SUMMARY

A previously healthy 65-year-old woman who had been experiencing left buttock pain radiating to the dorsum of the foot for 2 years visited our clinic. Prior to visiting the clinic, she underwent lumbar spine magnetic resonance imaging and received physiotherapy, pain killers, and epidural injections based on a presumptive diagnosis of spinal stenosis for 2 years in other hospitals. Repeat magnetic resonance imaging revealed joint connection of the articular branch of the hip joint and rostral extension of the cyst along the L5 spinal nerve near the L5-S1 neural foramen. The patient was diagnosed with intraneural ganglion cyst arising from the articular branch of the hip joint based on high-resolution magnetic resonance neurography. Using the arthroscopic approach, a cystic opening within the intra-articular space was detected, and cyst decompression was then performed. The pain in the left leg was significantly relieved during the 6-mo follow-up.

CONCLUSION

Although intraneural ganglion cysts arising from the hip joint are rare, they can cause typical radicular pain and mimic common L5 radiculopathy. Typical cyst ascent phenomenon starting from the termination of the articular branch on magnetic resonance imaging is a crucial finding indicative of intraneural ganglion cysts arising from the hip joint.

Prevalence of shoulder labral abnormalities on MRI in a non-athletic asymptomatic young adult population

OBJECTIVE

To determine the prevalence of shoulder (specifically labral) abnormalities on MRI in a young non-athletic asymptomatic cohort. We hypothesize that this population will have fewer labral abnormalities than an athletic population.

MATERIALS AND METHODS

In this cross-sectional study, non-athletic young adults age 18-29 with no history of shoulder pain received bilateral shoulder MRIs. A total of 58 total shoulder MRIs were completed on a 3-T MRI scanner (PRISMA-Fit Siemens Medical). MRIs were read by two board-certified fellowship-trained musculoskeletal radiologists at two time points 3 months apart to determine prevalence of labral and other shoulder anatomy abnormalities. Kappa statistics and the associated 95% confidence intervals were computed for inter/intra-reader reliability. Fisher's exact test was used to compare rates of abnormalities in our study with a similarly designed study involving ice hockey athletes.

RESULTS

Prevalence of labral abnormalities was 9% (5/58). Kappa coefficient was 1.0 for both readers for intra-reader reliability and 0.57 for inter-reader reliability of labral abnormalities. We further compared our results in asymptomatic athletes with previously published work using the same protocol at our institution. The prevalence of labral abnormalities on MRI in asymptomatic professional and collegiate ice hockey players (49 imaged shoulders) was 24%, which demonstrated a statistically significant (p value < 0.05) difference compared with our data with a p value of 0.03.

CONCLUSIONS

Non-athletic young adults with no history of shoulder pain/injury had an overall prevalence of shoulder MRI abnormalities less than asymptomatic professional and collegiate ice hockey players in a similarly designed study.

The origin and evolution of the euarthropod labrum

A widely (although not universally) accepted model of arthropod head evolution postulates that the labrum, a structure seen in almost all living euarthropods, evolved from an anterior pair of appendages homologous to the frontal appendages of onychophorans. However, the implications of this model for the interpretation of fossil arthropods have not been fully integrated into reconstructions of the euarthropod stem group, which remains in a state of some disorder. Here I review the evidence for the nature and evolution of the labrum from living taxa, and reconsider how fossils should be interpreted in the light of this. Identification of the segmental identity of head appendage in fossil arthropods remains problematic, and often rests ultimately on unproven assertions. New evidence from the Cambrian stem-group euarthropod Parapeytoia is presented to suggest that an originally protocerebral appendage persisted well up into the upper stem-group of the euarthropods, which prompts a re-evaluation of widely-accepted segmental homologies and the interpretation of fossil central nervous systems. Only a protocerebral brain was implicitly present in a large part of the euarthropod stem group, and the deutocerebrum must have been a relatively late addition.

The dimensions of the hip labrum can be reliably measured using magnetic resonance and computed tomography which can be used to develop a standardized definition of the hypoplastic labrum

PURPOSE

The purpose of this study was to examine the existing literature to determine the dimensions of the acetabular labrum, with a focus on hypotrophic labra, including the modalities and accuracy of measurement, factors associated with smaller labra, and any impacts on surgical management.

METHODS

Four databases (PubMed, Ovid [MEDLINE], Cochrane Database, and EMBASE) were searched from database inception to January 2020. Two reviewers screened the literature independently and in duplicate. Methodological quality of included papers was assessed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. Where possible, data on labral size were combined using a random effects model.

RESULTS

Twenty-one studies (5 level II, 9 level III, 7 level IV) were identified. This resulted in 6,159 patients (6,436 hips) with a mean age of 34.3 years (range 8.4-85). The patients were 67.3% female with an average follow-up of 57.3 months. There was no consistent definition of labral size quoted throughout the literature. The mean width on MRI/MRA was 7.3 mm (95% CI 6.9-7.8 mm), on computed tomography arthrography was 8.7 mm (95% CI 8.0-9.3), and during arthroscopy was 5.0 mm (95% CI 4.9-5.2). Inter-observer reliability was good to excellent in all modalities. Labral hypotrophy may be associated with increased acetabular coverage. Hypertrophic labra were highly associated with acetabular dysplasia (r = - 0.706, - 0.596, - 0.504, respectively; P < 0.001).

CONCLUSION

Labral width can reliably be measured utilizing imaging techniques including magnetic resonance and computed tomography. The pooled mean labral width was 6.2 mm, and height 4.6 mm. The establishment of a gold-standard of measurement on arthroscopy and advanced imaging would aid in clinical decision-making regarding treatment options for patients presenting with a painful hip, particularly those with hypoplastic labra, and provide radiological guidelines for standardized labrum size classifications.

LEVEL OF EVIDENCE

Level IV.

Does labral repair have a clinical benefit during arthroscopic treatment of femoro-acetabular impingement? Prospective multicentre study with 2-year follow-up

INTRODUCTION

Hip arthroscopy has emerged as an effective tool for treating labral tears associated with femoro-acetabular impingement (FAI).

OBJECTIVE

Compare the effectiveness of debridement versus labral repair on functional outcomes at 2 years after hip arthroscopy and evaluate the influence of the repair technique.

HYPOTHESIS

There is no statistical difference in short-term functional outcomes between debridement and repair. The type of repair technique has no influence on functional outcomes.

METHODS

From July 2017 to June 2018, a prospective study was done at 10 participating hospitals specialised in hip preservation surgery. Patients over 18 years of age, who underwent hip arthroscopy for a labral tear due to femoro-acetabular impingement, were enrolled. Patients underwent either labral repair or debridement. The labral repairs were performed with either the loop or mattress technique and functional outcomes were evaluated using the Non-Arthritic Hip Score (NAHS).

RESULTS

One hundred and eighty-seven patients who underwent arthroscopic treatment for FAI were enrolled; 42 (22.5%) underwent labral debridement and 145 (77.5%) underwent labral repair. In the repair group, 66 (46%) were mattress sutures and 79 (54%) were loop sutures. Mean patient age was 33.3±10.3 (18-63) and 38% of patients were women (n=71). Mean follow-up was 16.2 months (10-26.4). The mean NAHS improved from 47.3 to 72.8 (p<0.05) at final follow-up. There was no significant difference between the repair and debridement groups (p>0.05). There was no significant difference between the mattress and loop repair subgroups (p>0.05).

CONCLUSIONS

There is no statistical difference in short-term functional outcomes between debridement and repair. The type of repair technique has no influence on functional outcomes.

LEVEL OF EVIDENCE

II, prospective cohort study.

THE SUCCESS OF RETURN TO SPORT AFTER SUPERIOR LABRUM ANTERIOR TO POSTERIOR (SLAP) TEARS: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Reviews on superior labral anterior to posterior (SLAP) injuries have been reported in the literature. However, current reviews have not focused on the success of athletes return to their previous level of sport or athletic performance.

Hypothesis/Purpose

Systematically review return to sport (RTS) and return to sport at previous level (RTSP) proportions after SLAP injury while reporting any additional performance metrics and outcome measures.

Study Design

Systematic Review & Meta-Analysis.

Methods

A computer assisted literature search of MEDLINE, CINAHL, Embase and SportDiscus databases utilizing keywords related to RTS post-surgery for SLAP tear was implemented. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were utilized for study methodology. Quality assessment utilized the MINORS scale.

Results

Twenty-two studies (617 athletes) qualified for analysis. Based on limited evidence from level 3b to 4 studies, athletes RTS post intervention for SLAP injury occurred at a rate of 93% (95% CI:87 to 98%) and overall RTSP rate was 72% (95% CI:60 to 83%). The mean time to RTS post intervention was reported in 59% of studies at 6.9 ± 2.9 months. Patient reported outcome measures (PROM's) were reported in 86% of studies. There was limited reporting of performance statistics, rehabilitation guidelines, return to sport criteria, and information regarding SLAP diagnosis in the available studies. None of the included studies reported post-surgical athletic performance or career longevity.

Conclusions

Limited evidence suggests that less than three in four athletes return to their previous level of sport participation after SLAP injury intervention. Treatment success for an athlete with SLAP injury remains relatively unknown as only 59% of included studies clearly delineate RTS from RTSP and neither athletic performance nor career longevity were reported in any included studies. Future studies of higher quality are required for this determination.

Level of Evidence

Level 1a.

A comprehensive review of the normal, abnormal, and post-operative MRI appearance of the proximal biceps brachii

The biceps brachii myotendinous unit, particularly the long head of the biceps tendon and its labral attachment, is a common cause of shoulder and arm pain. Its complex anatomy and normal variations can present a challenge when interpreting MR images. The purpose of this manuscript is to review the proximal biceps anatomy, variants, pathology, and post-operative appearance as seen on MRI. Recent data regarding the accuracy of clinical examination and MRI will be summarized.

Expression profile of matrix metalloproteinases in the labrum of femoroacetabular impingement

Aims

Femoroacetabular impingement (FAI) is a potential cause of hip osteoarthritis (OA). The purpose of this study was to investigate the expression profile of matrix metalloproteinases (MMPs) in the labral tissue with FAI pathology.

Methods

In this study, labral tissues were collected from four FAI patients arthroscopically and from three normal hips of deceased donors. Proteins extracted from the FAI and normal labrums were separately applied for MMP array to screen the expression of seven MMPs and three tissue inhibitors of metalloproteinases (TIMPs). The expression of individual MMPs and TIMPs was quantified by densitometry and compared between the FAI and normal labral groups. The expression of selected MMPs and TIMPs was validated and localized in the labrum with immunohistochemistry.

Results

On MMP arrays, most of the targeted MMPs and TIMPs were detected in the FAI and normal labral proteins. After data normalization, in comparison with the normal labral proteins, expression of MMP-1 and MMP-2 in the FAI group was increased and expression of TIMP-1 reduced. The histology of the FAI labrum showed disorderly cell distribution and altered composition of thick and thin collagen fibres. The labral cells expressing MMP-1 and MMP-2 were localized and their percentages were increased in the FAI labrum. Immunohistochemistry confirmed that the percentage of TIMP-1 positive cells was reduced in the FAI labrum.

Conclusion

This study established an expression profile of MMPs and TIMPs in the FAI labrum. The increased expression of MMP-1 and MMP-2 and reduced expression of TIMP-1 in the FAI labrum are indicative of a pathogenic role of FAI in hip OA development.

Cite this article:Bone Joint Res. 2020;9(4):173–181.

Hip morphology in mucopolysaccharidosis type IVA through radiograph, magnetic resonance imaging and arthrogram assessment

PURPOSE

This study examined the hip morphology of paediatric patients with mucopolysaccharidosis (MPS) type IVA (MPS IVA).

METHODS

This was a retrospective chart review of 42 hips in 21 children with MPS IVA. Pelvic radiographs and magnetic resonance imaging (MRI) scans of 42 hips and arthrograms of 13 hips were analysed. The bony, cartilaginous and labral coverage of the acetabulum was determined by acetabular index (AI), centre edge angle (CEA) and femoral head coverage (FHC).

RESULTS

The mean age at the time of radiography was 66.3 ± 21.7 months. The bony, cartilaginous and labral AI in the MRI assessment were 36.3 ± 5.3, 18.3 ± 4.7 and 12.1 ± 4.6 degrees, respectively. The inter-class correlation coefficients (ICCs) for the bony AI, CEA and FHC measurements on radiographs and MRI were 0.936, 0.879 and 0.810, respectively. In the MRI assessment, labrum in 12 of 42 hips appeared as a regular triangle, and it was flat on 30/42 hips. The average arthrographic AI (AAI) was 11.1 ± 2.7 degrees. The ICCs value of AAI versus cartilaginous and labral AI on MRI indicates good agreement but higher in labral AI.

CONCLUSION

Hips in MPS IVA exhibited obvious cartilage and labrum compensation in response to abnormal ossification of bony acetabulum. Cartilage in MPS IVA hip increases the thickness in the longitudinal direction, while the labrum becomes flatten in the horizontal direction. The AAI may represent intraoperative labrum coverage. The femora-acetabular harmony is difficult to determine using radiography only, and pre-operative MRI and an intraoperative arthrogram are very important in a hip assessment in MPS IVA.

Thrower's Shoulder: An Approach to MR Imaging Interpretation

In this article, the authors aim to focus on the challenges of interpreting shoulder MR imaging in the throwing athlete with an approach formed by evidence-based literature and clinical experience, with a particular focus on superior labrum tears.

Posterior Shoulder Instability: What to Look for

Posterior shoulder instability is often hard to diagnose with clinical examination. Patients generally present with vague pain, weakness, and/or joint clicking but less frequently complaining of frank sensation of instability. Imaging examinations, especially MR imaging and magnetic resonance arthrography, have a pivotal role in the identification and management of this condition. This review describes the pathologic micro/macrotraumatic magnetic resonance features of posterior shoulder instability as well as the underlying joint abnormalities predisposing to this condition, including developmental anomalies of the glenoid fossa, humeral head, posterior labrum, and capsular and ligamentous structures.

[From Pathomorphology to Hip Osteoarthritis - Femoroacetabular Impingement as an Example]

From Pathomorphology to Hip Osteoarthritis - Femoroacetabular Impingement as an Example Abstract. Femoroacetabular impingement (FAI) occurs due to abnormal morphology and subsequent contact between the proximal femur and the acetabulum and can be a source of labral and chondral damage in the hip joint. While there is evidence that Cam-type FAI is correlated with hip osteoarthritis, there is yet no clear link between osteoarthritis and Pincer-FAI in which primarily the labrum gets injured. Hips with evident deformity and beginning chondral and/or labral damage should undergo surgery. Most cases (80-90 %) can be successfully treated by hip arthroscopy. At the time of surgery, the typical FAI-patient is 30 years old. With correct indication and proper surgical technique, favorable outcomes are achieved in more than 80 % of the cases at a short- to mid-term follow-up.

six3 acts upstream of foxQ2 in labrum and neural development in the spider Parasteatoda tepidariorum

Anterior patterning in animals is based on a gene regulatory network, which comprises highly conserved transcription factors like six3, pax6 and otx. More recently, foxQ2 was found to be an ancestral component of this network but its regulatory interactions showed evolutionary differences. In most animals, foxQ2 is a downstream target of six3 and knockdown leads to mild or no epidermal phenotypes. In contrast, in the red flour beetle Tribolium castaneum, foxQ2 gained a more prominent role in patterning leading to strong epidermal and brain phenotypes and being required for six3 expression. However, it has remained unclear which of these novel aspects were insect or arthropod specific. Here, we study expression and RNAi phenotype of the single foxQ2 ortholog of the spider Parasteatoda tepidariorum. We find early anterior expression similar to the one of insects. Further, we show an epidermal phenotype in the labrum similar to the insect phenotype. However, our data indicate that foxQ2 is positioned downstream of six3 like in other animals but unlike insects. Hence, the epidermal and neural pattering function of foxQ2 is ancestral for arthropods while the upstream role of foxQ2 may have evolved in the lineage leading to the insects.

Labral calcification plays a key role in hip pain and symptoms in femoroacetabular impingement

BACKGROUND

Hip osteoarthritis (HOA) is the most common hip disorder and a major cause of disability in the adult population, with an estimated prevalence of end-stage disease and total hip replacement. Thus, the diagnosis, prevention, and treatment of the early stages of the disease in young adults are crucial to reduce the incidence of end-stage HOA. The purpose of this study was to determine whether (1) a relationship among the inflammatory status of labrum and synovium collected from patients with femoroacetabular impingement (FAI) would exist; and (2) to investigate the associations among the histopathological features of joint tissues, the pre-operative symptoms and the post-operative outcomes after arthroscopic surgery.

METHODS

Joint tissues from 21 patients undergoing hip arthroscopy for FAI were collected and their histological and immunohistochemical features were correlated with clinical parameters.

RESULTS

Synovial mononuclear cell infiltration was observed in 25% of FAI patients, inversely correlated with the hip disability and osteoarthritis outcome score (HOOS) pain and function subscales and with the absolute and relative change in total HOOS. All the labral samples showed some pattern of degeneration and 67% of the samples showed calcium deposits. The total labral score was associated with increased CD68 positive cells in the synovium. The presence of labral calcifications, along with the chondral damage worsened the HOOS post-op symptoms (adjusted R-square = 0.76 p = 0.0001).

CONCLUSIONS

Our study reveals a relationship between the histologic labral features, the synovial inflammation, and the cartilage condition at the time of FAI. The presence of labral calcifications, along with the cartilage damage and the synovitis negatively affects the post-operative outcomes in patients with FAI.

There is poor accuracy in documenting the location of labral and chondral lesions observed during hip arthroscopy

Purpose

To determine and compare the accuracy and interobserver reliability of the different methods for localizing acetabular labral, acetabular chondral, and femoral head chondral lesions with hip arthroscopy .

Methods

Three cadaver hips were placed in the supine position. Three labral, three femoral chondral, and six acetabular chondral lesions were made in each cadaver using electrocautery. Six surgeons classified the lesions according to different classification systems (clock-face, geographic, Method-G) using hip arthroscopy and standardized portals. Identification of each lesion was performed after conclusion of the study through open dissection and surgical hip dislocation to be used as the “gold-standard.” Accuracy was calculated as the number of correct answers divided by total number of responses for a given system. The interobserver reliability was calculated using the kappa coefficient. The different classification methods were compared. All P values were reported with significance set at P < 0.05.

Results

The clock-face method had an accuracy of 74% (95% CI, 60%–85%) and interobserver reliability of 0.19 (95% CI, 0.11–0.26) while the geographic method had an accuracy of 50% (95% CI, 36%–64%) and interobserver reliability of 0.21 (95% CI, 0.05–0.31) for acetabular labral lesion identification (P > 0.05). The acetabular chondral lesion identification accuracy was 56% (95% CI, 46%–65%) for Method G, 66% (95% CI, 56%–75%) for Method G-simp, and 63% (95% CI, 53%–72%) for the geographic system (P > 0.05) with an interobserver reliability of 0.31 (95% CI, 0.27–0.35), 0.34 (95% CI, 0.28–0.40), and 0.40 (95% CI, 0.34–0.45), respectively (P > 0.05). Femoral chondral lesion identification accuracy was 74% (95% CI, 60%–85%) for Method G, 43% (95% CI, 29%–57%) for the geographic method, and 59% (95% CI, 45%–72%) for the geographic-simp system with interobserver reliability of 0.37 (95% CI, 0.27–0.47), 0.34 (95% CI, 0.28–0.40), and 0.40 (95% CI, 0.29–0.51), respectively (P > 0.05). Method G was significantly more accurate than the geographic system (P = 0.001).

Conclusions

There was poor to fair accuracy and interobserver reliability of the reporting systems for localization of labral, acetabular chondral, and femoral chondral lesions encountered during hip arthroscopy. The study suggests there is a need for a new method that is easy to use, reliable, reproducible and accurate.

Ultrasound of glenoid labrum with MR arthrographic correlation

Ultrasound (US) is a reliable non-invasive method to image the rotator cuff tendons. Even though glenoid labral pathology is common, it is not routinely looked at as part of the shoulder ultrasound protocol. Currently, the gold standard for labral imaging remains MR arthrography. However, given the rather long waiting list and cost implications, US may be used as a modality to quickly screen the shoulder for gross labral pathology. Whilst there is relative paucity of the literature outlining labral pathology on US, there is none correlating sonographic and corresponding MRI appearances. We present a pictorial review highlighting scanning positioning, US and corresponding MRI appearances of a normal labrum and various labral pathologies. We discuss useful scanning tips and characteristic US signs which can help the radiologist.

The anatomical properties of the indirect head of the rectus femoris tendon: a cadaveric study with clinical significance for labral reconstruction surgery

BACKGROUND

Acetabular labral tear is a common pathology. In some clinical situations, primary labral repair may not be possible and labral reconstruction is indicated.

PURPOSE AND CLINICAL RELEVANCE

Describe the anatomy of the indirect head of the rectus femoris (IHRF) tendon with clinical application in arthroscopic labral reconstruction surgery.

METHODS

Twenty-six cadaver hips were dissected. Thirteen measurements, each with clinical relevance to arthroscopic labral reconstruction using an IHRF tendon graft were taken on each hip. All measurements were taken in triplicate. Mean values, standard deviations and intra-observer reliability were calculated.

RESULTS

The mean footprint of the direct head of the rectus femoris tendon was 10.6 mm × 19.6 mm. The width and thickness at the confluence of both heads were 10.9 mm and 6.9 mm, respectively. The mean total length of the footprint and "free portion" of the IHRF was 55.3 mm, the mean cranial to caudal footprint measured at the 12 o'clock, 1 o'clock, and 2 o'clock positions were 22.3 mm. The mean length of the Indirect Head footprint alone was 38.1 mm. The mean length of IHRF tendon suitable for grafting was 46.1 mm and the mean number of clock face sectors covered by this graft was 3.3 clock face sectors. Intra-observer reliability was ≥ 0.90 for all recorded measurements. The origin of the IHRF on the acetabulum fans out posteriorly, becoming thinner and wider as the origin travels posteriorly. The tendon footprint is firmly attached on the lateral wall of the ilium and becomes a free tendon overlying the acetabular bone as it travels anteriorly and distally towards its muscular attachment.

CONCLUSION

The IHRF tendon is in an ideal location for harvesting and contains the appropriate thickness, length and triangular architecture to serve as a safe and local graft source for acetabular labral reconstruction surgery.

Altered shoulder kinematics using a new model for multiple dislocations-induced Bankart lesions

BACKGROUND

Many active individuals undergo multiple dislocations during the course of a season before surgical treatment without considering the implications of each successive injury. Therefore, the purpose of this study was to develop a multiple dislocation model for the glenohumeral joint and evaluate the resulting changes in joint function.

METHODS

Eight cadaveric shoulders were evaluated using a robotic testing system. A simulated clinical exam was performed by applying a 50 N anterior load to the humerus at 60° of glenohumeral abduction and external rotation. Each joint was then dislocated. The same loads were applied again and the resulting kinematics were recorded following each of 10 dislocations. The force required to achieve dislocation was recorded and capsulolabral status was assessed.

FINDINGS

A reproducible Bankart lesion was repeatedly created following the dislocation protocol. The force required for all dislocations significantly decreased following the 1st dislocation. In addition, even lower forces were required to achieve the 5th and subsequent dislocations (p < 0.05). Anterior translation in response to an anterior load during the simulated clinical exam increased between the intact and injured joints (p < 0.05). However, anterior translation reached a plateau following the 3rd to 10th dislocations and was increased compared with the 1st dislocation (p < 0.05).

INTERPRETATION

A repeatable Bankart lesion was not surgically made, but created by our new dislocation model. Joint function appeared to reach a constant level after the 3rd to 5th dislocations. Thus, multiple dislocations result in a deleterious dose dependent effect suggesting additional damage is not sustained after the fifth dislocation.

LEVEL OF EVIDENCE

Controlled laboratory study.

Femoroacetabular impingement: question-driven review of hip joint pathophysiology from asymptomatic skeletal deformity to end-stage osteoarthritis

Femoroacetabular impingement (FAI), together with its two main pathomechanisms, cam and pincer, has become a trending topic since the end of the 1990s. Despite massive academic research, this hip disorder still conceals obscure aspects and unanswered questions that only a question-driven approach may settle. The pathway that leads a FAI asymptomatic morphology through a FAI syndrome to a FAI-related osteoarthritis is little known. Contact mechanics provides a shareable and persuasive perspective: cam FAI is based on shear contact stress at joint level with consequent cartilage wear; pincer FAI, contrariwise, determines normal contact stress between acetabular rim and femoral neck and squeezes the labrum in between, with no cartilage wear for many years from the onset. Pincer prognosis is then far better than cam. As a matter of fact, cartilage wear releases fragments of extracellular matrix which in turn trigger joint inflammation, with consequently worsening lubrication and further enhanced wear. Inflammation pathobiology feeds pathotribology through a vicious loop, finally leading to hip osteoarthritis. The association of cam and pincer, possibly overdiagnosed, is a synergic combination that may damage the joint rapidly and severely. The expectations after FAI surgical correction depend strictly on chondral layer imaging, on time elapsed from the onset of symptoms and on clinic-functional preoperative level. However, preemptive surgical correction is not recommended yet in asymptomatic FAI morphology. LEVEL OF EVIDENCE: V.

Incidence of gadolinium or fluid signal within surgically proven glenoid labral tears at MR arthrography

OBJECTIVE

To determine how often patients with surgically proven labral tears have labral signal on shoulder MR arthrography (MRA) that is not equal to gadolinium or fluid on T1- and T2-weighted images, respectively.

MATERIALS AND METHODS

Consecutive patients with surgical repair of a SLAP or Bankart labral tear within 95 days of an MRA were included. Using cartilage signal as an internal reference, two musculoskeletal (MSK) radiologists retrospectively categorized labral signal as T1-hyperintense, T1-gadolinium, T2-hyperintense, or T2-fluid. In patients without T1-gadolinium or T2-fluid labral signal, secondary findings such as the orientation, extent, shape, and width of the abnormal signal was recorded. Statistical analyses were performed using Fisher's test and ANOVA.

RESULTS

Sixty-one labral tears (36 SLAP and 25 Bankart) in 54 patients (mean age, 30.7; F:M 8:46) met the inclusion criteria. In 67% and 76% of SLAP and Bankart labral tears, T1-gadolinium signal was present (p = 0.43). T2-fluid signal was present in 50% and 92% of these same labral tears (p = 0.001). The absence of T1-gadolinium or T2-fluid signal was more common in SLAP tears (33%) compared to Bankart tears (8%) (p = 0.02). In the SLAP cases, at least two secondary findings of a SLAP tear were present in 92% (11/12).

CONCLUSIONS

Lack of surfacing T1-gadolinium or T2-fluid labral signal is unusual in Bankart tears but relatively common in SLAP tears. However, a SLAP tear was diagnosed in 92% of these 12 cases when two secondary findings were present.

Hip Arthroscopy of a Painful Hip with Borderline Dysplasia

Purpose

Hip arthroscopy has been considered for treating hip dysplasia; however, its efficacy is still a matter of controversy. Here, we report outcomes of patients with borderline dysplasia treated with a contemporary hip arthroscopy technique.

Materials and Methods

Forty-seven hips with borderline hip dysplasia were treated using hip arthroscopy. Patients underwent procedures to correct torn labrums or ligamentum teres with additional procedure on the acetabular capsule. Patient outcomes were assessed using visual analogue scale (VAS), modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS) and patient satisfaction. Risk factors for poor prognosis were also investigated.

Results

The mean follow up period was 25.9 months. At the last follow up, mean VAS score decreased from 6.1±1.6 to 3.5±2.8 (P=0.016). The mHHS and NHAS at the last follow up improved from 61.0±7.6 to 78.6±19.5 (P=0.001) and 62.1±7.5 to 80.0±18.5 (P=0.002), respectively. While significant improvement was observed in all patient reported outcome measures tested, 19 (40.4%) hips indicated that “the operation was unsatisfactory.” The only factor shown to influence outcomes was preoperative VAS (i.e., worse scores potentially an indicator of poor outcomes).

Conclusion

The results of the current study indicate that arthroscopic management may be beneficial for a subset of patients with borderline dysplasia; however, the dissatisfaction rate associated with this treatment approach may be as high as 40%. The poor preoperative pain score appears to be the sole indicator for poor outcomes.

The Extension-Thickness-Damage (ETD) score: a pre-operative hip MR arthrography-based classification to predict type of labrum surgery

INTRODUCTION

Hip magnetic resonance arthrography (MRA) is the pre-operative imaging modality of choice in patients with labral damage, with several classifications of labral tears having been reported based on MRA findings. Nevertheless, none of the available classification systems allows the surgeon to predict before surgery how a labral tear could be treated. Our purpose was to develop a new MRA-based scoring system of labral tears to predict before surgery the treatment option more suitable for labral tears.

MATERIALS AND METHODS

Forty-seven patients (29 males and 18 females; mean age: 35.9 ± 12.4) performed hip MRA for suspicious of femoroacetabular impingement and were afterwards subjected to arthroscopic treatment. Two musculoskeletal radiologists reviewed all pre-operative examinations and provided the Extension-Thickness-Damage score for each patient, based on Extension of tear, Thickness of labrum, and type of Damage. Chondral lesions grading was based on the arthroscopic findings according to Konan classification. For statistical purposes, patients were divided into two groups, depending on the type of treatment: labral repair or debridement. Mann-Whitney U, Chi-square, receiver operator curves, and Cohen kappa statistics were used.

RESULTS

35/47 underwent repair, while 12/47 were debrided. In both groups, the median chondral damage was grade III, with no significant differences (p = 0.439). The median Extension-Thickness-Damage score in the repair group (6) was significantly lower (p < 0.001) than that in the debridement group (8). The highest diagnostic performance (area under the curve) of Extension-Thickness-Damage was 0.819. The inter-observer agreement was substantial in the evaluation of Extension (k = 0.626) and Thickness (k = 0.771), and almost perfect for Damage (k = 0.827). Higher scores of Extension and Thickness were more frequently associated with debridement (p < 0.001; p = 0.0016, respectively), with no significant differences on the basis of Damage parameter (p = 0.284).

CONCLUSIONS

The MRA-based Extension-Thickness-Damage score could represent a helpful pre-operative tool, expressing the extent of the damage and its reparability before arthroscopy.

Surgical treatment outcomes after primary vs recurrent anterior shoulder instability

INTRODUCTION

The aim of this study is to compare the outcomes of surgical management after primary anterior shoulder dislocation to the outcomes of patients who have surgical stabilization after recurrent anterior shoulder instability.

METHODS

A Medline (PubMed) search was performed in November of 2016 using the following key terms: shoulder, labrum, Bankart, instability, repair, outcome, recurrent. In May 2017 a Cochrane search was performed using similar key terms to ensure we included all studies. Only level I and II studies were included.

RESULTS

There were three studies that compared primary repair to delayed repair. In all three studies, the rate of recurrence was higher in group R than group S. When pooled, there was not a statistically significant difference between these groups, but there was a slightly higher odds of recurrence in group R (pooled OR 2.08, CI 0.69-6.26, p = 0.19). No significant differences were appreciated in functional outcomes or complications in these two groups.

CONCLUSION

Further level I and level II studies to compare surgical treatment after first time and recurrent instability are needed. This study failed to find a statistically significant difference in recurrence rates in patients who had stabilization acutely after a single episode compared to patients with recurrent instability events, although results suggest there may be a small benefit in primary stabilization.

A Treatment-Based Algorithm for the Management of Type-II SLAP Tears

Background:

The management of Type-II superior labral tears (SLAP) of the shoulder remains a controversial topic. Treatment ranges from non-operative management to surgical management including SLAP repair, biceps tenotomy, and biceps tenodesis. An optimal treatment algorithm has yet to reach universal acceptance.

Objective:

The goal of this paper was to provide a treatment algorithm for the management of Type-II SLAP tears based on current literature and expert opinion.

Method:

Current literature was reviewed and expert opinion was reported to develop a comprehensive treatment protocol for patients based on age, activity level, and pathology.

Results:

Operative management of type-II SLAP tears yields good to excellent outcomes when proper indications are followed. Biceps tenodesis may produce more reliable pain relief and functional improvement when compared to primary SLAP repair in patients over the age of 40.

Conclusion:

When non-operative management of Type-II SLAP tears fails, operative management yields good to excellent outcomes in most patients. Primary SLAP repair should be performed in patients under the age of 40 with no evidence of proximal biceps pathology, while biceps tenodesis can provide consistent pain relief and return to activity in patients over the age of 40 or with significant proximal biceps pathology. Tenotomy should be reserved for elderly or low demand individuals.

Diagnosis of glenoid labral tears using 3-tesla MRI vs. 3-tesla MRA: a systematic review and meta-analysis

BACKGROUND

Various protocols exist for magnetic resonance arthrogram (MRA) of the shoulder, including 3D isotropic scanning and positioning in neutral (2D neutral MRA), or abduction-external-rotation (ABER).

HYPOTHESIS

MRA does not improve diagnostic accuracy for labral tears when compared to magnetic resonance imaging (MRI) performed using 3-Tesla (3T) magnets.

METHOD

Systematic review of the Cochrane, MEDLINE, and PubMed databases according to PRISMA guidelines. Included studies compared 3T MRI or 3T MRA (index tests) to arthroscopic findings (reference test). Methodological appraisal performed using QUADAS-2. Pooled sensitivity and specificity were calculated.

RESULTS

Ten studies including 929 patients were included. Index test bias and applicability were a concern in the majority of studies. The use of arthroscopy as the reference test raised concern of verification bias in all studies. For anterior labral lesions, 3T MRI was less sensitive (0.83 vs. 0.87 p = 0.083) than 3T 2D neutral MRA. Compared to 3T 2D neutral MRA, both 3T 3D Isotropic MRA and 3T ABER MRA significantly improved sensitivity (0.87 vs. 0.95 vs. 0.94). For SLAP lesions, 3T 2D neutral MRA was of similar sensitivity to 3T MRI (0.84 vs. 0.83, p = 0.575), but less specific (0.99 vs. 0.92 p < 0.0001). For posterior labral lesions, 3T 2D neutral MRA had greater sensitivity than 3T 3D Isotropic MRA and 3T MRI (0.90 vs. 0.83 vs. 0.83).

CONCLUSIONS

At 3-T, MRA improved sensitivity for diagnosis of anterior and posterior labral lesions, but reduced specificity in diagnosis of SLAP tears. 3T MRA with ABER positioning further improved sensitivity in diagnosis of anterior labral tears.

LEVEL OF EVIDENCE

IV.

Diagnosis and Treatment of Injuries to the Biceps and Superior Labral Complex in Overhead Athletes

PURPOSE OF REVIEW

This review discusses the diagnostic and treatment challenges presented by injuries to the biceps and superior labral complex.

RECENT FINDINGS

A focused patient history, numerous physical examination maneuvers, and appropriate advanced imaging studies must be utilized to reach an accurate diagnosis. Nonoperative management, even in overhead athletes, has demonstrated relatively good outcomes, while operative outcomes have yielded mixed results. The surgeon must take into account a number of variables when choosing the appropriate surgical procedure: labral repair versus biceps tenodesis. Rehabilitation, either as nonoperative management or as a postoperative protocol, should focus on restoring glenohumeral and scapulothoracic strength, endurance, and full, pain-free range of motion, while correcting any deficiencies in balance or rhythm throughout the overhead motion. Despite the operative treatment challenges that SLAP tears present, with new techniques and proper patient selection, overhead athletes with injuries to the biceps and superior labrum complex can return to sport at a high level.

Hip chondrolabral mechanics during activities of daily living: Role of the labrum and interstitial fluid pressurization

Osteoarthritis of the hip can result from mechanical factors, which can be studied using finite element (FE) analysis. FE studies of the hip often assume there is no significant loss of fluid pressurization in the articular cartilage during simulated activities and approximate the material as incompressible and elastic. This study examined the conditions under which interstitial fluid load support remains sustained during physiological motions, as well as the role of the labrum in maintaining fluid load support and the effect of its presence on the solid phase of the surrounding cartilage. We found that dynamic motions of gait and squatting maintained consistent fluid load support between cycles, while static single-leg stance experienced slight fluid depressurization with significant reduction of solid phase stress and strain. Presence of the labrum did not significantly influence fluid load support within the articular cartilage, but prevented deformation at the cartilage edge, leading to lower stress and strain conditions in the cartilage. A morphologically accurate representation of collagen fibril orientation through the thickness of the articular cartilage was not necessary to predict fluid load support. However, comparison with simplified fibril reinforcement underscored the physiological importance. The results of this study demonstrate that an elastic incompressible material approximation is reasonable for modeling a limited number of cyclic motions of gait and squatting without significant loss of accuracy, but is not appropriate for static motions or numerous repeated motions. Additionally, effects seen from removal of the labrum motivate evaluation of labral reattachment strategies in the context of labral repair.

[Arthroscopic soft tissue stabilization of posttraumatic anterior shoulder instability : Techniques, limitations and long-term results]

Arthroscopic soft tissue stabilization is a well-established and broadly accepted procedure to treat posttraumatic shoulder instability. Advantages in comparison to open stabilization procedures include improved visualization of the structural damage and a less invasive approach. Technical developments in recent years have led to further improvement of the arthroscopic technique for shoulder instability. This article presents a description of principles and new developments as it contains basic techniques including patient positioning, access portals, preparation of the glenoid bone, soft tissue handling and shuttle techniques. Modern suture anchor systems to achieve arthroscopic stabilization with the corresponding advantages and disadvantages are also presented. Furthermore, the limitations and long-term results of arthroscopic soft tissue stabilization are discussed.

Microarchitecture of the tsetse fly proboscis

Background

Tsetse flies (genus Glossina) are large blood-sucking dipteran flies that are important as vectors of human and animal trypanosomiasis in sub-Saharan Africa. Tsetse anatomy has been well described, including detailed accounts of the functional anatomy of the proboscis for piercing host skin and sucking up blood. The proboscis also serves as the developmental site for the infective metacyclic stages of several species of pathogenic livestock trypanosomes that are inoculated into the host with fly saliva. To understand the physical environment in which these trypanosomes develop, we have re-examined the microarchitecture of the tsetse proboscis.

Results

We examined proboscises from male and female flies of Glossina pallidipes using light microscopy and scanning electron microscopy (SEM). Each proboscis was removed from the fly head and either examined intact or dissected into the three constituent components: Labrum, labium and hypopharynx. Our light and SEM images reaffirm earlier observations that the tsetse proboscis is a formidably armed weapon, well-adapted for piercing skin, and provide comparative data for G. pallidipes. In addition, the images reveal that the hypopharynx, the narrow tube that delivers saliva to the wound site, ends in a remarkably ornate and complex structure with around ten finger-like projections, each adorned with sucker-like protrusions, contradicting previous descriptions that show a simple, bevelled end like a hypodermic needle. The function of the finger-like projections is speculative; they appear to be flexible and may serve to protect the hypopharynx from influx of blood or microorganisms, or control the flow of saliva. Proboscises were examined after colonisation by Trypanosoma congolense savannah. Consistent with the idea that colonisation commences in the region nearest the foregut, the highest densities of trypanosomes were found in the region of the labrum proximal to the bulb, although high densities were also found in other regions of the labrum. Trypanosomes were visible through the thin wall of the hypopharynx by both light microscopy and SEM.

Conclusions

We highlight the remarkable architecture of the tsetse proboscis, in particular the intricate structure of the distal end of the hypopharynx. Further work is needed to elucidate the function of this intriguing structure.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2367-2) contains supplementary material, which is available to authorized users.