The acetabular labrum seal: a poroelastic finite element model

Mid-term results of autologous matrix-induced chondrogenesis for large chondral defects in hips with femoroacetabular impingement syndrome

Aims

The purpose of this study was to evaluate the mid-term outcomes of autologous matrix-induced chondrogenesis (AMIC) for the treatment of larger cartilage lesions and deformity correction in hips suffering from symptomatic femoroacetabular impingement (FAI).

Methods

This single-centre study focused on a cohort of 24 patients with cam- or pincer-type FAI, full-thickness femoral or acetabular chondral lesions, or osteochondral lesions ≥ 2 cm2, who underwent surgical hip dislocation for FAI correction in combination with AMIC between March 2009 and February 2016. Baseline data were retrospectively obtained from patient files. Mid-term outcomes were prospectively collected at a follow-up in 2020: cartilage repair tissue quality was evaluated by MRI using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Patient-reported outcome measures (PROMs) included the Oxford Hip Score (OHS) and Core Outcome Measure Index (COMI). Clinical examination included range of motion, impingement tests, and pain.

Results

A total of 12 hips from 11 patients were included (ten males, one female, mean age 26.8 years (SD 5.0), mean follow-up 6.2 years (SD 5.2 months)). The mean postoperative MOCART score was 66.3 (SD 16.3). None of the patients required conversion to total hip arthroplasty. Two patients had anterior impingement. External hip rotation was moderately limited in four patients. There was a correlation between MOCART and follow-up time (rs = -0.61; p = 0.035), but not with initial cartilage damage, age, BMI, or imaging time delay before surgery. PROMs improved significantly: OHS from 37.4 to 42.7 (p = 0.014) and COMI from 4.1 to 1.6 (p = 0.025). There was no correlation between MOCART and PROMs.

Conclusion

Based on the reported mid-term results, we consider AMIC as an encouraging treatment option for large cartilage lesions of the hip. Nonetheless, the clinical evidence of AMIC in FAI patients remains to be determined, ideally in the context of randomized controlled trials.

The Windshield Wiper Sign Is an Instability-Related Osteochondral Defect of the Anterolateral Femoral Head

PURPOSE

To investigate a radiographic sign believed to be indicative of hip instability and acetabular suction seal disruption in the native hip, coined the "windshield wiper" (WSW) sign.

METHODS

A retrospective review was performed for patients who underwent periacetabular osteotomy (PAO) with the senior author between March 2021 and September 2023. A WSW sign was identified on plain films as a concave or flat osteochondral defect on the anterolateral femoral head extending medial to the head-neck junction with resultant loss of femoral head sphericity in the native hip. Every patient underwent a standardized series of radiographs, as well as computed tomography and magnetic resonance imaging. All patients underwent arthroscopy before PAO to address intra-articular pathology and other indicated procedures. The osteochondral defect and resultant suction seal disruption were verified during arthroscopy. These patients were then compared with a control group of arthroscopically treated hips without hip instability.

RESULTS

Of 250 patients reviewed, a total of 19 hips in 17 patients (prevalence of 7.6%) demonstrated radiographic evidence of the WSW sign. All patients with a WSW sign presented with symptomatic clinical hip instability requiring a PAO. The mean patient age was 31.2 years, with a mean lateral center-edge angle (LCEA) of 14.3°. There were 13 hips (68.4%) with dysplasia, 4 (21.1%) with borderline dysplasia, and 2 (10.5%) with a normal LCEA. All patients with a WSW sign and LCEA ≥ 20° displayed significant femoral antetorsion abnormalities. All arthroscopic videos and images demonstrated a compromised suction seal. Of the 50 control group hips reviewed, the WSW sign was not identified.

CONCLUSIONS

The WSW sign is an uncommon radiographic finding in patients with hip instability. When identified, it can be predictive of substantial instability, especially in cases which are otherwise considered borderline dysplasia or normal based on LCEA.

LEVEL OF EVIDENCE

Level III, retrospective comparative case control study.

Structure, composition and anisotropic swelling of the bovine acetabular labrum

The fibro-cartilaginous labrum surrounds the acetabular rim and is important for hip joint stability and sealing. Sealing may be enhanced by swelling pressure within the normal labrum. Swelling of the degenerated or torn labrum might occur and potentially contribute to the development of osteoarthritis, through altered load transmission. This study aimed to characterize the three-dimensional swelling behaviour, the collagen fiber orientation and spatial proteoglycan distribution of the bovine acetabular labrum. Specimens were harvested from bovine donors (192-652 days, male, n = 6 donors). Structure was analyzed by scanning electron microscopy, histology, and dimethylmethylene blue assay. Specimen dimensions were measured before and after incubation in phosphate buffered saline to assess the swelling. Results showed that the articulating surface is composed of a collagen mesh network. Collagen fiber bundles showed a low degree of alignment close to the surface and were circumferentially aligned in the deep tissue. Proteoglycans were identified clustered between the collagen bundles. Glycosaminoglycan content was 10 x lower than that of cartilage (23.1 ± 6.4 compared to 299.5 ± 19.1 μg/mg dry weight) with minor regional differences. Specimens swelled significantly more in the orthogonal direction (swelling ratio 124.7 ± 10.2%) compared to the swelling parallel to the articulating surface (108.8 ± 6.1% and 102.8 ± 4.1%). In the deep tissue, swelling was also restricted in the main collagen fiber bundle direction (circumferentially), with a swelling ratio of 109.5 ± 4.0% in the main fiber bundle direction compared to 126.8 ± 7.3 % and 122.3 ± 5.8% radially. The findings demonstrate that the labrum shows anisotropic swelling properties, which reflect the anisotropy in the tissue structure and inter-fiber localisation of proteoglycans.

Labral Reconstruction via Capsular Augmentation Maintains Perfusion to the Acetabular Labrum and Locally Transferred Autograft: An in Vivo Laser Doppler Flowmetry Analysis

Background

The purpose of the present study was to examine the effects of arthroscopic labral repair with capsular augmentation on blood flow in vivo with use of laser Doppler flowmetry (LDF) to measure microvascular perfusion of the labrum and autograft tissue.

Methods

The present prospective case series included patients ≥18 years old who underwent arthroscopic acetabular labral repair with capsular augmentation; all procedures were performed by a single surgeon between 2018 and 2022. The LDF probe measured microvascular blood flow flux within 1 mm3 of the surrounding labral and capsular tissue of interest. Mean baseline measurements of flux were compared with readings immediately following capsular elevation and after completing labral augmentation. Blood flux changes were expressed as the percent change from the baseline measurements.

Results

The present study included 41 patients (24 men [58.5%] and 17 women [41.5%]) with a mean age (and standard deviation) of 31.3 ± 8.4 years, a mean BMI of 24.6 ± 3.4 kg/m2, a mean lateral center-edge of angle 35.3° ± 4.9°, a mean Tönnis angle of 5.8° ± 5.8°, and a mean arterial pressure of 93.7 ± 10.9 mm Hg. Following capsular elevation, the mean percent change in capsular blood flow flux was significantly different from baseline (-9.24% [95% confidence interval (CI), -18.1% to -0.04%]; p < 0.001). Following labral augmentation, the mean percent change in labral blood flow flux was significantly different from baseline both medially (-22.3% [95% CI, -32.7% to -11.9%]; p < 0.001) and laterally (-32.5% [95% CI, -41.5% to -23.6%]; p = 0.041). There was no significant difference between the changes in medial and lateral perfusion following repair (p = 0.136).

Conclusions

Labral repair with capsular augmentation sustains a reduced blood flow to the native labrum and capsular tissue at the time of fixation. The biological importance of this reduction is unknown, but these findings may serve as a benchmark for other labral preservation techniques and support future correlations with clinical outcomes.

Level of Evidence

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

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.

The acetabular labrum tissue shows unique transcriptome signatures compared to cartilage and responds to combined cyclic compression and surface shearing

The labrum is a fibrocartilaginous ring surrounding the acetabulum. Loss of labrum function contributes to the degeneration of the hip joint, leading to osteoarthritis. Successful labrum restoration requires profound knowledge about the tissue being replaced. The aim of this study was to characterize the transcriptome and the mechanobiological function of the labrum. RNA-seq was performed to compare the transcriptome of bovine labrum against articular cartilage tissue. Differential expression and gene ontology (GO) term pathway analysis were applied using the SUSHI framework. Bovine labrum explants were cultured for 5 days with / without mechanical loading and targeted gene expression was analyzed by real time quantitative polymerase chain reaction. More than 6'000 genes were significantly differentially expressed in the labrum compared to cartilage. Up- and downregulated genes were associated with the GO term extracellular matrix organization. The study established an extracellular matrix gene expression profile of healthy labrum tissue and identified significantly upregulated extracellular matrix related genes compared to cartilage tissue. Mechanical loading significantly upregulated aggrecan (ACAN), cartilage oligomeric matrix protein (COMP), fibronectin (FN1) and proteoglycan 4 (PRG4). MMP1/3/9 and IL6, which were upregulated by an inflammatory stimulus (IL-1b), were statistically unaffected by the loading, although IL6 was upregulated in each donor immediately after the loading. Unique ECM related features may guide the development of labrum tissue-engineering solutions. Despite the transcriptome differences between labrum and cartilage tissue, gene expression response to mechanical loading showed similarities with previously reported responses in cartilage, indicating a preserved tissue adaptation mechanism to mechanical loading. Running title: Acetabular Labrum Mechanobiology.

Diagnostic value of magnetic resonance imaging and magnetic resonance arthrography for assessing acetabular labral tears: A systematic review and meta-analysis

BACKGROUND

This study aimed to systematically evaluate the value of magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) in the diagnosis of acetabular labral tears.

METHODS

Databases including PubMed, Embase, Cochrane Library, Web of Science, CBM, CNKI, WanFang Data, and VIP were electronically searched to collect relevant studies on magnetic resonance in the diagnosis of acetabular labral tears from inception to September 1, 2021. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias in the included studies by using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. RevMan 5.3, Meta Disc 1.4, and Stata SE 15.0 were used to investigate the diagnostic value of magnetic resonance in patients with acetabular labral tears.

RESULTS

A total of 29 articles were included, involving 1385 participants and 1367 hips. The results of the meta-analysis showed that the pooled sensitivity, pooled specificity, pooled positive likelihood ratio, pooled negative likelihood ratio, pooled diagnostic odds ratio, area under the curve of the summary receiver operating characteristic, and Q* of MRI for diagnosing acetabular labral tears were 0.77 (95% confidence interval [CI], 0.75-0.80), 0.74 (95% CI, 0.68-0.80), 2.19 (95% CI, 1.76-2.73), 0.48 (95% CI, 0.36-0.65), 4.86 (95% CI, 3.44-6.86), 0.75, and 0.69, respectively. The pooled sensitivity, pooled specificity, pooled positive likelihood ratio, pooled negative likelihood ratio, pooled diagnostic odds ratio, area under the curve of the summary receiver operating characteristic, and Q* of MRA for diagnosing acetabular labral tears were 0.87 (95% CI, 0.84-0.89), 0.64 (95% CI, 0.57-0.71), 2.23 (95% CI, 1.57-3.16), 0.21 (95% CI, 0.16-0.27), 10.47 (95% CI, 7.09-15.48), 0.89, and 0.82, respectively.

CONCLUSION

MRI has high diagnostic efficacy for acetabular labral tears, and MRA has even higher diagnostic efficacy. Due to the limited quality and quantity of the included studies, the above results should be further validated.

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 Vascularization Course of Labral Autograft and Its Effect on Tissue Healing: Acetabular Labral Augmentation Versus Labral Reconstruction in a Porcine Model

BACKGROUND

The preservation of the native labral vascularization is assumed to be the potential advantage of acetabular labral augmentation, the effect of which remains unknown.

PURPOSE

To identify the vascular distribution within the labral autograft and its effect on the healing process between labral augmentation (AUG) and reconstruction (RECON) in a porcine model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 36 pigs randomly underwent unilateral labral augmentation or reconstruction (AUG group, n = 18; RECON group, n = 18). The pigs were randomly sacrificed at 6, 12, and 24 weeks postoperatively. The labral autografts were harvested for macroscopic evaluation and histologic assessment. The labral autograft was zoned into 2 halves to observe the vascular distribution: the capsular half (zone I) and the articular half (zone II). Each zone was divided into 2 parts: the peripheral part (IA and IIA) and the part attached to the acetabulum (IB and IIB).

RESULTS

At 6 weeks, there existed more vascular ingrowth in zone I, whereas zone IIB appeared nearly avascular in both groups. At 12 weeks, the area with the greatest vascularity was zone II in the RECON group and zone IA in the AUG group. The vascularity was concentrated at zones IA and IIA in both groups at 24 weeks. The labral autografts were hypertrophic with sufficient filling of the labral defect in both groups at 6 weeks. At 12 weeks, an insufficient volume of the articular half was observed in 3 of 6 labral autografts in the RECON group, while all autografts remained well integrated with the chondrolabral junction in the AUG group. At 24 weeks, unsatisfactory merging of the labral autograft with the cartilage at the articular side was found in 2 of 6 labral autografts in the RECON group, which was not observed in the AUG group despite the sufficient volume of autografts labrum in both groups.

CONCLUSION

Slow vascular ingrowth within the articular half might account for the poor healing of the reconstructed labral autograft. Labral augmentation provides the possibility of better tissue healing because of the preservation of the original chondrolabral junction compared with labral reconstruction.

CLINICAL RELEVANCE

Labral augmentation might be a feasible alternative to labral reconstruction under the condition of viable labral remnants.

Arthroscopic Acetabular Labral Repair Versus Labral Debridement: Long-term Survivorship and Functional Outcomes

Background:

Arthroscopic treatment for labral tears includes debridement and repair. Long-term studies have failed to demonstrate a difference between these treatments in terms of conversion to total hip arthroplasty (THA).

Purpose:

To investigate 2 different labral treatments, debridement and repair, using an adjusted analysis to evaluate long-term conversion to THA.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

This was a retrospective cohort study of patients who underwent hip arthroscopy by a single surgeon between April 2007 and October 2014. Postoperative follow-up information included conversion to THA, patient satisfaction, and patient-reported outcome measures (modified Harris Hip Score; Hip Outcome Score, Activities of Daily Living and Sports Specific subscales; International Hip Outcome Tool; Nonarthritic Hip Score; and Lower Extremity Functional Scale).

Results:

Of the 204 hips included in the study, 99 (48.5%) underwent labral repair, and 105 (51.5%) underwent debridement. In total, 28 (13.7%) of the 204 patients underwent conversion to THA within 10 years after hip arthroscopy (labral repair: 5 [5.0%] vs labral debridement: 23 [21.9%]). Labral repair was associated with a significantly lower risk of conversion to THA compared with debridement (hazard ratio [HR] = 0.24; 95% CI, 0.07-0.74; P = .014). Additional factors associated with risk of conversion to THA included older age at the time of arthroscopy (HR = 1.06 per year; 95% CI, 1.02-1.11; P = .002) and Tönnis grade (HR = 2.39; CI, 1.14-5.41; P = .026). Abrasion chondroplasty, acetabuloplasty, body mass index, Outerbridge grade, and radiographic femoroacetabular impingement were not found to be significantly associated with risk of THA. No significant difference in patient satisfaction was found between treatment groups, and for patients who did not convert to THA, there was no difference in mean patient-reported outcome scores at final follow-up.

Conclusion:

Patients who underwent labral repair were less likely to convert to THA compared with patients who underwent labral debridement, despite adjustment for differences in baseline patient characteristics and preexisting pathology. Additional factors associated with a lower rate of hip survival were older age and osteoarthritis at the time of hip arthroscopy.

Comparison of early outcomes of arthroscopic labral repair or debridement

Aims

This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum.

Methods

Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement.

Results

A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months.

Conclusion

Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III Cite this article: Bone Jt Open 2022;3(4):291–301.

Workers' Compensation Patients Improved After Hip Arthroscopy for Labral Tears: A 5-Year Outcome Propensity Score-Matched Study

BACKGROUND

The workers' compensation (WC) status has been associated with inferior outcomes in orthopaedic procedures and is usually excluded from clinical outcome studies. Therefore, comparative studies based on WC status are scarce.

PURPOSE

(1) To determine outcomes of patients with WC claims treated with hip arthroscopy for labral tears at a minimum 5-year follow-up and (2) to compare these findings with a propensity score-matched control group without WC claims.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients were propensity score matched to a control group without WC claims. Data were prospectively collected for all patients undergoing hip arthroscopy. Patients were included if they received primary hip arthroscopy for labral tears in the setting of femoroacetabular impingement, had a WC claim, and had preoperative and minimum 5-year follow-up patient-reported outcomes ([PROs]; modified Harris Hip Score [mHHS], Non-Arthritic Hip Score [NAHS], Hip Outcome Score-Sports Specific Subscale [HOS-SSS], and visual analog scale [VAS] for pain). Clinical outcomes were measured using the Patient Acceptable Symptom State (PASS), minimal clinically important difference (MCID), and maximum outcome improvement satisfaction threshold (MOI).

RESULTS

A total of 111 from 132 (84.1%) eligible WC patients met the inclusion criteria with an average follow-up time of 80.3 ± 37.3 months. WC cases demonstrated significant improvement from preoperatively to a minimum 5-year follow-up for mHHS, NAHS, HOS-SSS, and VAS for pain (P < .05). WC patients returned to work at a 66% rate, with an average clearance time of 4.7 months to light duty and 9.5 months to heavy duty. When compared with the control group, the WC group demonstrated lower pre- and postoperative PROs (P < .05); however, WC cases had a greater magnitude of improvement (ΔmHHS [P = .0012], ΔNAHS [P < .001], and ΔHOS-SSS [P = .012]). Rates of achieving MCID and MOI were similar in both groups (P > .05). The WC group went on to receive a future arthroscopy in 19 cases (17.1%), while 10 cases (4.5%) in the control group required revision arthroscopy (P < .001). Patients in both the WC and the control groups converted to total hip arthroplasty at similar rates (13.3% and 15.4%, respectively; P > .05).

CONCLUSION

Patients with WC claims treated with hip arthroscopic surgery showed significant improvement and high rates of returning to work at a minimum 5-year follow-up. Although having lower scores in PROs and achieving PASS rates, no differences were found in MCID and MOI rates. Furthermore, WC patients had a greater magnitude of improvement from preoperatively to a minimum 5-year follow-up after hip arthroscopy. Therefore, even though more studies are needed to determine the causes of inconsistent outcomes in the WC population, hip arthroscopy can effectively treat labral tears in the setting of femoroacetabular impingement, regardless of the WC status.

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.

Multicenter Outcomes After Primary Hip Arthroscopy: A Comparative Analysis of Two-Year Outcomes After Labral Repair, Segmental Labral Reconstruction, or Circumferential Labral Reconstruction

PURPOSE

(1) To report minimum 2-year follow-up patient-reported outcome measures in patients undergoing labral repair (LR), segmental labral reconstruction (SLR), or circumferential labral reconstruction (CLR) in the primary setting; and (2) to compare minimum 2-year follow-up patient-reported outcome measures among these groups.

METHODS

A retrospective review of a prospectively maintained multicenter database of patients undergoing hip arthroscopy was performed. Inclusion criteria were patients undergoing hip arthroscopy for treatment of labral tear and femoroacetabular impingement syndrome between January 2014 and October 2017, and completion of minimum 2-year postoperative outcome scores. Exclusion criteria were patients undergoing revision hip surgery, labral treatment limited to debridement, lateral center-edge angle <20°, osteoarthritis (Tönnis grade > 1), slipped capital femoral epiphysis, workers compensation status, and patients undergoing concomitant gluteus medius and/or minimus repair. Labral reconstruction patients were matched (1:3) with labral repair patients on age, sex, and body mass index. The labral reconstruction group was further stratified into SLR, and CLR groups. Patient demographic characteristics and clinical outcomes including Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sport Subscale, modified Harris Hip Score, international Hip Outcome Tool, and visual analog scale for pain were analyzed, as well as achievement of the minimal clinical improvement difference (MCID). A P-value less than .05 indicated statistical significance.

RESULTS

A total of 416 patients were included (LR, n = 312; SLR, n = 53; CLR, n = 51). The age, body mass index, and sex of the matched cohort were 42.3 ± 11.2 years, 24.7 ± 3.7, and 55.0% female. At a minimum of 2-year after hip arthroscopic surgery, no differences were found in preoperative, postoperative, or the delta visual analog scale for pain, modified Harris Hip Score, Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sport Subscale, or international Hip Outcome Tool. Subsequently, the proportion of patients achieving the MCID and the PASS at latest follow-up were analyzed. This analysis revealed that no significant differences in the rate of MCID or PASS achievement for any outcome measure existed based on labral treatment.

CONCLUSIONS

In this multicenter study on labral treatment in the primary setting, patients undergoing LR, SLR, and CLR demonstrated no difference in preoperative or postoperative scores, nor the proportion of patients achieving clinically significant outcome improvement.

LEVEL OF EVIDENCE

III; therapeutic outcome study with controls.

Female Athlete Hip Injuries: A Narrative Review

OBJECTIVE

In this narrative review, we highlight sex-specific anatomic and biomechanical features of the hip region in female athletes, as well as the potential impact of these characteristics on observed disparities in both intra-articular and extra-articular injury patterns between female and male athletes. It is our goal to broaden the scope of knowledge related to hip pathology in active female athletes among sports medicine providers with the hope of better optimizing sport participation and performance in female athletes.

DATA SOURCES

A literature review was conducted using PubMed database and Google Scholar search engine. Search terms included sport, female, athlete, sex differences, injury, hip, and all diagnoses discussed in this review. Cross-reference of these articles identified additional resources.

MAIN RESULTS

Sex-specific differences in both static design and dynamic function contribute to disparities in hip injury patterns between female and male athletes. Intra-articular injuries, including labral and ligamentum teres pathology, as well as extra-articular injuries, including iliopsoas tendon dysfunction, gluteal and proximal hamstring tendinopathy, ischiofemoral impingement, bone stress injuries, and certain nerve entrapment syndromes, seem to affect female athletes more commonly than male counterparts.

CONCLUSIONS

Given unique anatomic and functional considerations, the growing population of female athletes worldwide warrants specialized care and consideration. Potential predisposition to specific hip injuries should be taken into consideration during diagnostic evaluation of hip pain in the female athlete.

Autograft Versus Allograft: The Evidence in Hip Labral Reconstruction and Augmentation

BACKGROUND

Labral augmentation and labral reconstruction have emerged as essential procedures for restoring the anatomic and functional characteristics of the hip joint in patients with a deficient hip labrum or irreparable labral tear.

HYPOTHESIS/PURPOSE

The purpose of this study was to compare allograft and autograft hip labral reconstruction and augmentation. We hypothesized that autografts would entail fewer revision arthroscopic procedures.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients were identified who underwent labral reconstruction or labral augmentation using iliotibial band (ITB) allograft or ITB autograft performed by a single surgeon between 2011 and 2017. Patient-reported outcome measures collected before surgery and at minimum 2-year follow-up included the following: Hip Outcome Score Activities of Daily Living and Hip Outcome Score Sports-Specific Subscale and, at follow-up, patient satisfaction (range, 1-10, with 10 being very satisfied). Patients followed a standardized rehabilitation protocol after surgery with relative individualization to address each patient's needs. For continuous variables, comparisons between allografts and autografts were made using Student t tests or Mann-Whitney tests. Categorical comparisons were assessed using chi-square or Fisher exact test. Multiple logistic regression was performed to determine the influence of graft choice on risk of revision or THA.

RESULTS

A total of 205 hips met 2-year inclusion criteria. ITB allografts were used for 55 patients (37 augmentations, 18 reconstructions) and ITB autografts for 150 patients (34 augmentations, 116 reconstructions). Females represented a greater proportion of allograft versus autograft patients (71% vs 46%, respectively; P = .001). Overall, autograft patients had larger alpha angles (66.6° vs 59.1°; P = .001) and longer grafts (46 vs 41 mm; P = .03) compared with allograft patients. A total of 13 (23.6%) patients required revision surgery in the allograft group compared with 11 (7.3%) in the autograft group (P < .001). After controlling for sex, procedure (reconstruction vs augmentation), and previous surgery, the odds of revision were higher for allograft patients (OR, 4.1; 95% CI, 1.5-11.6). No significant differences in conversion to THA were observed between groups (allograft = 9%; autograft = 6%; P = .50), even after adjustment for the above covariates (OR, 2.3; 95% CI, 0.6-7.9). No differences in postoperative patient-reported outcome measures or patient satisfaction were observed between groups.

CONCLUSION

Labral augmentation or reconstruction with autograft has a significantly lower revision rate than labral augmentation or reconstruction with allograft.

Magnetic Resonance Arthrographic Findings After Hip Labrum Resection Versus Refixation

The aim of this study was to evaluate whether new tissue formation occurs after labral debridement/excision, and, if so, which morphological features are typical for a neo-labrum. The authors further compared the findings after labrum resection with those seen after labrum refixation. Patients with femoroacetabular impingement who underwent hip arthroscopy or surgical hip dislocation to address a labrum pathology were retrospectively included, and postoperative magnetic resonance arthrography studies were assessed. Forty-two patients had undergone either labrum resection (n=25) or refixation (n=17), performed arthroscopically (47.6%) or via surgical hip dislocation (52.4%). In the subgroup of patients after debridement/resection, there was anterosuperior/superior scar tissue in 83.5%, with amorphous configuration in 92%, irregular surface in approximately two-thirds of the cases, and a mean±SD thickness of 7.0±2.7 mm. A labrum-like shape of the scar plate was seen in 7.7%. Regarding the subgroup of patients who had undergone labral refixation, an irregular or rounded labrum shape was noted in 26.5% and 51.3% of cases, respectively, with a triangular shape in less than one-fourth of cases. Labrum re-tears (35.7%) were mainly observed at the base (71.7%), rather than within the labral substance (28.4%). New tissue formation can be observed in the majority of cases after excision of the hip labrum, with amorphous and irregular surface configuration compared with a native labrum. This new tissue should therefore be referred to as scar tissue rather than as neo-labrum. Whether scar tissue is inferior to a refixed labrum needs to be further elucidated in follow-up studies. [Orthopedics. 2021;44(4):e607-e613.].

Circumferential and Segmental Arthroscopic Labral Reconstruction of the Hip Utilizing the Knotless Pull-Through Technique with All-Suture Anchors

Appropriate labral tear management is one of the principal priorities of hip-preservation surgery. The labrum's role in the stability and biomechanics of the hip and preservation of the suction seal has been thoroughly demonstrated. Favorable patient-reported outcomes with labral reconstruction and, more recently, labral augmentation have shown that these are viable reconstructive procedures in the setting of irreparable labra. A wide variety of grafts have been used for these advanced labral restoration techniques. The present Technical Note will describe a detailed arthroscopic circumferential labral reconstruction using the pull-through technique with knotless all-suture anchors. The benefits of such can be applied to both segmental and circumferential labral reconstruction procedures, as well as labral augmentation, based on the intraoperative findings and preference of the surgeon.

Multicenter Outcomes After Revision Hip Arthroscopy: Comparative Analysis of 2-Year Outcomes After Labral Repair Versus Labral Reconstruction

BACKGROUND

There is a paucity of literature evaluating patient outcomes in patients undergoing revision labral repair and labral reconstruction.

PURPOSE

To compare outcomes in patients undergoing revision hip arthroscopy for treatment of labral tears by labral repair or labral reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective review of a prospectively maintained multicenter database of patients undergoing hip arthroscopy was performed. An a priori power analysis determined that a total of 62 patients were required. Patients undergoing revision hip arthroscopy for labral tears with completed 2-year outcome scores were included. Patients undergoing primary hip arthroscopy, labral debridement, concomitant gluteal repair, and patients with hip dysplasia (lateral center-edge angle <20°) were excluded. Patients were grouped into revision labral repair and labral reconstruction groups. Patient demographics and patient-reported outcomes (PROs) including Hip Outcome Score - Activities of Daily Living, Hip Outcome Score - Sport Subscale, modified Harris Hip Score, international Hip Outcome Tool-12, visual analog scale for pain and satisfaction, and achievement of minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) were analyzed.

RESULTS

A total of 40 patients underwent revision labral repair and 55 patients underwent labral reconstruction. Patients undergoing revision labral repair were younger (mean age, 30.0 ± 10.7 years vs 34.4 ± 9.7 years; P = .048), had lower rates of labral degeneration (25.0% vs 62.7%; P = .004), and had lower rates of severe complexity of tears (21.1% vs 66.0%; P = .003). However, the labral repair group had higher rates of articular cartilage damage (62.5% vs 33.3%; P = .009). There were no differences in any preoperative or 2-year postoperative PROs. Furthermore, no differences were seen in achievement of MCID or PASS in any PRO.

CONCLUSION

In this multicenter study on revision hip arthroscopy, patients undergoing revision labral repair were younger and had better labral characteristics but greater cartilage damage compared with patients undergoing labral reconstructions. Despite these differences, patients who underwent labral repair reported similar outcomes to those undergoing labral reconstruction.

Proximal Overresection During Femoral Osteochondroplasty Negatively Affects the Distractive Stability of the Hip Joint: A Cadaver Study

BACKGROUND

Contact between the acetabular labrum and articular cartilage of the femoral head creates a suction seal that helps maintain stability of the femoral head in the acetabulum. A femoral osteochodroplasty may occasionally extend proximally into the femoral head, diminishing the articular surface area available for sealing contact.

PURPOSE

To determine whether proximal overresection decreases the rotational and distractive stability of the hip joint.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six hemipelvises in the following conditions were tested: intact, T-capsulotomy, osteochondroplasty to the physeal scar, and 5- and 10-mm proximal extension. The pelvis was secured to a metal plate, and the femur was potted and attached to a multiaxial hip jig. Specimens were axially distracted using a load from 0 to 150 N. For rotational stability testing, 5 N·m of internal and external torque was applied. Both tests were performed at different angles of flexion (0°, 15°, 30°, 60°, 90°). Displacement and rotation were recorded using a 3-dimensional motion tracking system.

RESULTS

The T-capsulotomy decreased the distractive stability of the hip joint. A femoral osteochondroplasty up to the physeal scar did not seem to affect the distractive stability. However, a proximal extension of the resection by 5 and 10 mm increased axial instability at every angle of flexion tested, with the greatest increase observed at larger angles of flexion (P < .01). External rotation increased significantly after T-capsulotomy in smaller angles of flexion (0°, P = .01; 15°, P = .01; 30°, P = .03). Femoral osteochondroplasty did not create further external rotational instability, except when the resection was extended 10 mm proximally and the hip was in 90° of flexion (P = .04).

CONCLUSION

This cadaveric study demonstrated that proximal extension of osteochondroplasty into the femoral head compromises the distractive stability of the hip joint but does not affect hip rotational stability.

CLINICAL RELEVANCE

Clinically, this study highlights the importance of accuracy when performing femoral osteochondroplasty to minimize proximal extension that may increase iatrogenic instability of the hip joint.

Perpendicular drill bit alignment provides a practical guidance to determine the appropriate suture anchor insertion angle during acetabular labral repair

The safe acetabular rim angle is an anatomical measurement used to determine the safety margin when inserting suture anchors. The purpose of the present study was to find out whether aligning the drill bit perpendicularly during arthroscopic surgery can provide a reference point for determining an appropriate angle to facilitate the suture anchor insertion and to prevent extra- and intra-articular perforations. One hundred computed tomographic hips were used to reconstruct three-dimensional acetabular hip models. Each model was radially sectioned at the 4 o’clock, 3 o’clock and anterior inferior iliac spine (AIIS) positions (that corresponded mainly to the 2:20 clock position). A perpendicular reference line, representing a perpendicular drill bit alignment, was drawn for each position within the acetabular model, and its relation to the safe acetabular rim angle was measured. The length of the perpendicular reference line and the effect of gender on measurements were also evaluated. The mean safe acetabular rim angle at the 3 o’clock position was significantly smaller compared to other clock positions (P < 0.001). The perpendicular reference line was located out of the safe acetabular rim angle in 28 cases (%28), mostly in female acetabula at the 3 o’clock position, and relative to the perpendicular reference line the required minimal angle was 4° ± 2.3° to place the anchor in the safe acetabular rim angle to avoid extra-articular perforation. The perpendicular reference line was shortest at the 3 o’clock position, and its mean length was shorter in female acetabula at all clock positions (P < 0.001). Aligning the drill bit perpendicular to the acetabular opening plane during an arthroscopic anchor placement is a practical way to estimate and target the position of the safe acetabular rim angle to avoid anchor perforations. Based on measurements from a perpendicularly aligned drill bit, the drill bit should be directed towards the joint minimally by 4° to avoid extra-articular perforations and maximally by 30° to avoid intra-articular perforations.

Minimum 2-Year Functional Outcomes of Patients Undergoing Capsular Autograft Hip Labral Reconstruction

BACKGROUND

There is a paucity of literature on arthroscopic capsular autograft labral reconstruction.

PURPOSE

To report midterm functional outcomes for patients undergoing acetabular labral repair with capsular autograft labral reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This is a retrospective case series of prospectively collected data on patients who underwent arthroscopic acetabular labral repair by the senior surgeon between March 2013 and August 2018. The inclusion criteria for this study were adult patients aged 18 years or older who underwent primary hip arthroscopy for arthroscopic capsular autograft labral reconstruction. Exclusion criteria were <2 years of postoperative follow-up, elective disenrollment from study before 2-year follow-up, or repeat ipsilateral hip surgery before 2-year follow-up. Intraoperatively, patients underwent capsular autograft hip labral reconstruction if they were found to have a labrum with hypoplastic tissue (width <5 mm), complex tearing, or frank degeneration of native tissue. Clinical outcome data consisted of patient-reported outcome measures.

RESULTS

A total of 97 hips (94 patients) met the inclusion criteria with a mean final follow-up of 28.2 months (95% CI, 26.0-30.4). Patients had a mean age of 39.0 years (95% CI, 36.8-41.2) with a mean body mass index of 25.8 (95% CI, 24.9-26.7). When compared with baseline (40.4 [95% CI, 36.7-44.2]), the mean international Hip-Outcome Tool-33 (iHOT-33) scores were significantly greater at 3-month (60.9 [95% CI, 56.8-64.9]; P < .001), 6-month (68.8 [95% CI, 64.7-72.9]; P < .001), 12-month (73.2 [95% CI, 68.9-77.5]; P < .001), and final (76.6 [95% CI, 72.4-80.8]; P < .001) follow-up. At 2-year follow-up, 76.3%, 65.5%, and 60.8% of patients' iHOT-33 scores exceeded clinically meaningful outcome thresholds for minimally clinically important difference (MCID), patient-acceptable symptomatic state, and substantial clinical benefit, respectively.

CONCLUSIONS

In this study of 97 hips undergoing arthroscopic labral repair with capsular autograft labral reconstruction, we found favorable outcomes that exceeded the MCID thresholds in the majority of patients at a mean 28.2 months' follow-up. Future studies should compare outcomes between this technique and other methods of autograft and allograft reconstruction to determine differences in patient-reported outcomes, donor-site morbidity, and complications.

Is Arthroscopic Hip Labral Repair/Reconstruction Surgery Effective for Treating Femoroacetabular Impingement in the Presence of Osteoarthritis?

OBJECTIVE

To investigate clinical outcomes after arthroscopic labral preservation surgery for femoroacetabular impingement (FAI) in the presence of osteoarthritis (OA) compared with FAI without significant OA.

DESIGN

Retrospective case-control study.

SETTING

Department of Orthopaedic Surgery and Sports Medicine, Hospital of Academic Institute.

PATIENTS

Femoroacetabular impingement patients (n = 97; ≥35 years) undergoing arthroscopic FAI correction with labral preservation surgery from March 2009 to April 2014 were enrolled in this study.

INTERVENTIONS

Patients were divided into 2 groups: FAI group (79 patients), with Tonnis grade 0 or 1, and FAI + OA group (18 patients), with Tonnis grade 2 or 3.

MAIN OUTCOME MEASURES

We examined the clinical outcomes using the Modified Harris Hip Score (MHHS), Nonarthritic Hip Score (NAHS), and the conversion rate to total hip arthroplasty (THA).

RESULTS

No significant differences existed between the 2 groups with respect to age, sex, follow-up period, or preoperative MHHS or NAHS. The mean MHHS and NAHS at the final follow-up were significantly lower in the FAI + OA group than in the FAI group. There was a significant difference in the rate of conversion to THA and failure between the 2 groups (THA 5% vs 50%) (failure 15% vs 67%).

CONCLUSION

Patients with FAI in the presence of OA did not improve after arthroscopic labral preservation surgery and had a high conversion rate to THA.

LEVEL OF EVIDENCE

Level III.

Acetabular labral reconstruction with medial meniscal allograft: preliminary results of a new surgical technique

PURPOSE

Reconstruction of the acetabular labrum during femoroacetabular impingement (FAI) surgery is accepted when the labrum is deficient and irreparable. Here we describe a novel technique using fresh-frozen medial meniscal allograft for labral reconstruction during surgical hip dislocation for correction of pincer FAI due to acetabular overcoverage.

METHODS

The results from seven hips (six patients) that underwent this procedure with 1 year minimum follow-up, and radiographs are presented.

RESULTS

Six of the seven hips had improvements in pain, hip flexion, hip abduction, and Merle d'Aubigné-Postel scores. Only one patient with pre-existing osteoarthritis underwent reoperation with conversion to total hip arthroplasty. All digastric trochanteric osteotomies healed, and there were no cases of femoral head osteonecrosis or progression of Tönnis grades.

CONCLUSIONS

The medial meniscus is a morphologically and clinically suitable option for labral reconstruction and effectively restores the hip fluid seal.

Consensus-based classification system for intra-operative management of labral tears during hip arthroscopy-aggregate recommendations from high-volume hip preservation surgeons

The purpose of this study was to survey high-volume hip preservation surgeons regarding their perspectives on intra-operative management of labral tears to improve decision-making and produce an effective classification system. A cross-sectional survey of high-volume hip preservation surgeons was conducted in person and anonymously, using a questionnaire that is repeated for indications of labral debridement, repair and reconstruction given the torn labra are stable, unstable, viable or non-viable. Twenty-six high-volume arthroscopic hip surgeons participated in this survey. Provided the labrum was viable (torn tissue that is likely to heal) and stable, labral debridement would be performed by 76.92% of respondents for patients >40 years of age and by >84% of respondents for stable intra-substance labral tears in patients without dysplasia. If the labrum was viable but unstable, labral repair would be performed by >80% of respondents for patients ≤40 years of age and > 80% of respondents if the labral size was >3 mm and located anteriorly. Presence of calcified labra or the Os acetabuli mattered while deciding whether to repair a labrum. In non-viable (torn tissue that is unlikely to heal) and unstable labra, labral reconstruction would be performed by 84.62% of respondents if labral size was <3 mm. The majority of respondents would reconstruct calcified and non-viable, unstable labra that no longer maintained a suction seal. Surgeons performing arthroscopic hip labral treatment may utilize this comprehensive classification system, which takes into consideration patient age, labral characteristics (viability and stability) and bony morphology of the hip joint. When choosing between labral debridement, repair or reconstruction, consensus recommendations from high-volume hip preservation surgeons can enhance decision-making.

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.

Generalized Joint Hypermobility Is Associated With Decreased Hip Labrum Width: A Magnetic Resonance Imaging-Based Study

Purpose

To explore the relationship between generalized joint hypermobility and hip labrum width.

Methods

A retrospective review was performed of a single-surgeon database containing patients who underwent hip arthroscopy between 2014 and 2017. Patients were assessed for generalized laxity via Beighton Test Scoring (BTS), which tests for hyperextension of the fifth metacarpophalangeal joint, thumb apposition, elbow hyperextension, knee hyperextension, and trunk flexion on a 9-point scale. Patients were stratified into a "high BTS cohort" with a BTS ≥4, and a control cohort with BTS <4. Magnetic resonance imaging measurements of labral width for each patient were conducted by 2 blinded, musculoskeletal fellowship-trained radiologists at standardized "clockface" locations using a previously validated technique. Statistical analyses used to determine associations between BTS and labral width included Mann-Whitney U and Fisher exact testing as well as linear regression.

Results

Thirty-four patients met inclusion criteria (17 cases, 17 controls). Both groups were composed exclusively of female patients. There was no significant difference between cases or controls in terms of age (33.3 ± 10.4 years vs 35.2 ± 8.3 years, P = .57) or body mass index (26.1 ± 9.3 vs 23.6 ± 3.4, P = .36). The high Beighton score cohort had significantly thinner labrae at the indirect rectus (5.35 ± 1.2 mm vs 7.1 ± 1.1 mm, P < .001) and anterosuperior position (5.53 ± 1.4 mm vs 7.27 ± 1.6 mm, P = .003). There was no statistical difference between the high Beighton score cohort and controls at the psoas U position (6.47 ± 1.6 mm vs 7.43 ± 1.7 mm, P = .112). Linear regression analysis demonstrated Beighton score was significantly negatively associated with labrum width at the indirect rectus position (R² = 0.33, P < .001) and the anterosuperior position (R² = 0.25, P = .004).

Conclusions

Patients with a BTS ≥4 were found to have significantly thinner labra than those with a BTS of <4.

Level of Evidence

III, retrospective comparative trial.

The Efficacy of Labral Reconstruction: A Systematic Review

Background:

With a greater understanding of the importance of the acetabular labrum in the function of the hip, labral repair is preferred over debridement. However, in some scenarios, preservation or repair of the labrum is not possible, and labral reconstruction procedures have been growing in popularity as an alternative to labral resection.

Purpose:

To provide an up-to-date analysis of the literature to determine the overall efficacy of labral reconstruction when compared with labral repair or resection.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

PubMed, Embase, and MEDLINE databases were searched for literature regarding labral reconstruction in the hip before July 21, 2020. The results were screened and evaluated by 2 reviewers, and a third reviewer resolved any discrepancies. The final studies were evaluated using the MINORS (Methodological Index for Non-randomized Studies) score.

Results:

There were 7 comparative studies that fit the inclusion criteria, with 228 hips from 197 patients. The mean follow-up was 34.6 months, and the mean age of all patients was 38.34 years. There were slightly more female patients than male patients (105 vs 92). Arthroscopic reconstruction was performed in 86% of studies (6/7); open surgical techniques, in 14% (1/7). A variety of grafts was used in the reconstructions. The indications for labral reconstruction and outcome measures varied in these publications. Nine patients were lost follow-up, and 6 patients converted to total hip replacement postlabral reconstruction. The assessment of these comparative studies illustrated statistically equivalent results between labral reconstruction and labral repair. Comparisons of labral reconstruction with labral resection also showed statistically equivalent postoperative patient-reported outcome scores; however, the rates of conversion to total hip arthroplasty were significantly higher in the population undergoing resection.

Conclusion:

The review of current available comparative literature, which consists entirely of level 3 studies, suggests that labral reconstruction does improve postoperative outcomes but does not demonstrate superiority over repair. There may, however, be benefit to performing labral reconstruction over resection owing to the higher rate of conversion to total hip arthroplasty in the labral resection group.

Decreased Hip Labral Width Measured via Preoperative Magnetic Resonance Imaging Is Associated With Inferior Outcomes for Arthroscopic Labral Repair for Femoroacetabular Impingement

PURPOSE

To determine the association between labral width as measured on preoperative magnetic resonance imaging (MRI) and hip-specific validated patient self-reported outcomes at a minimum of 2 years' follow-up.

METHODS

We performed an institutional review board-approved retrospective review of prospectively gathered hip arthroscopy patients from 2010 to 2017. The inclusion criteria were defined as patients aged 18 to 65 years with radiographic evidence of femoroacetabular impingement who underwent a primary labral repair and had a minimum of 2 years' clinical follow-up. The exclusion criteria were defined as inadequate preoperative imaging, prior hip surgery, Tönnis grade 1 or higher, or lateral center-edge angle lower than 25°. An a priori power analysis was performed. MRI measurements of labral width were conducted by 2 blinded, musculoskeletal fellowship-trained radiologists at standardized "clock-face" locations using a previously validated technique. Outcomes were assessed using the Harris Hip Score (HHS), modified Harris Hip Score (mHHS), and Non-arthritic Hip Score (NAHS). For the mHHS, scores of 8 and 74 were used to define the minimal clinically important difference and patient acceptable symptomatic state, respectively. Patients were divided into groups by a labral width less than 1 SD below the mean (hypoplastic) or widths above 1 SD below the mean. Statistical analysis was performed using linear and polynomial regression; the Mann-Whitney U, χ², and Fisher exact tests; and intraclass correlation coefficient testing.

RESULTS

A total of 103 patients (107 hips) met the inclusion criteria (mean age, 39.4 ± 17 years; body mass index, 25.0 ± 4; 51% right sided; 68% female patients; mean follow-up, 76.5 ± 19.1 months [range, 30.0-113.0 months]). Mean labral width at the 11:30 clock-face position (indirect rectus), 3-o'clock position (psoas U), and 1:30 clock-face position (point halfway between the 2 aforementioned positions) was 7.1 ± 2.2 mm, 7.0 ± 2.0 mm, and 5.5 ± 1.9 mm, respectively. Intraclass correlation coefficient agreements were good to excellent between readers at all positions (0.83-0.91, P < .001). The preoperative HHS, mHHS, and NAHS were not statistically significantly different (P > .05) between the 2 groups. Sex, laterality, and body mass index were not predictive of outcomes (P > .05). The postoperative HHS, mHHS, and NAHS were found to be significantly lower in the hypoplastic group at each location tested (P < .01), including the mHHS at the 11:30 clock-face position (69 vs 87), 3-o'clock position (70 vs 87), and 1:30 clock-face position (71 vs 87). The proportion of patients with hypoplastic labra who reached the minimal clinically important difference was significantly lower (P < .001) at the 11:30 clock-face position (50% vs 91%), 3-o'clock position (56% vs 90%), and 1:30 clock-face position (58% vs 91%) in comparison to the non-hypoplastic labrum group. The proportion of patients with hypoplastic labra above the patient acceptable symptomatic state was significantly lower (P < .001) at the 11:30 clock-face position (44% vs 83%), 3-o'clock position (37.5% vs 84%), and 1:30 clock-face position (42% vs 85%) in comparison to the non-hypoplastic labrum group. Linear regression modeling was not significant at any position (P > .05). Polynomial regression was significant at the 11:30 clock-face position (R² = 0.23, P < .001), 3-o'clock position (R² = 0.17, P < .001), and 1:30 clock-face position (R² = 0.26, P < .004).

CONCLUSIONS

Hip labral width less than 1 SD below the mean measured via preoperative MRI was associated with significantly worse functional outcomes after arthroscopic labral repair and treatment of femoroacetabular impingement. The negative relation between labral width and outcomes may be nonlinear.

LEVEL OF EVIDENCE

Level IV, case series with subgroup analysis.

[Research progress in arthroscopic treatment of acetabular labrum injury]

Objective

To review the surgical methods of arthroscopy in the treatment of acetabular labrum injury, and to provide reference for clinical treatment.

Methods

The literature about the surgical methods and clinical results of hip arthroscopy in the treatment of acetabular labrum injury was reviewed and analyzed.

Results

In the early stages of hip arthroscopy, the removal of the torn labrum is the primary treatment option. The current principles of treatment are based on the specific circumstances of a torn labrum, including acetabular labrum debridement, acetabular labrum repair, acetabular labrum reconstruction, and acetabular labrum augmentation.

Conclusion

Hip arthroscopy has become the preferred technique for the treatment of acetabular labrum injury. Labral repair is still the first choice, and labral reconstruction is used when acetabular labrum injury cannot be repaired.

Hip preservation surgery and the acetabular fossa

As our understanding of hip function and disease improves, it is evident that the acetabular fossa has received little attention, despite it comprising over half of the acetabulum’s surface area and showing the first signs of degeneration. The fossa’s function is expected to be more than augmenting static stability with the ligamentum teres and being a templating landmark in arthroplasty. Indeed, the fossa, which is almost mature at 16 weeks of intrauterine development, plays a key role in hip development, enabling its nutrition through vascularization and synovial fluid, as well as the influx of chondrogenic stem/progenitor cells that build articular cartilage. The pulvinar, a fibrofatty tissue in the fossa, has the same developmental origin as the synovium and articular cartilage and is a biologically active area. Its unique anatomy allows for homogeneous distribution of the axial loads into the joint. It is composed of intra-articular adipose tissue (IAAT), which has adipocytes, fibroblasts, leucocytes, and abundant mast cells, which participate in the inflammatory cascade after an insult to the joint. Hence, the fossa and pulvinar should be considered in decision-making and surgical outcomes in hip preservation surgery, not only for their size, shape, and extent, but also for their biological capacity as a source of cytokines, immune cells, and chondrogenic stem cells.

Cite this article: Bone Joint Res 2020;9(12):857–869.

Use of a 3D Virtually Reconstructed Patient-Specific Model to Examine the Effect of Acetabular Labral Interference on Hip Range of Motion

Background:

The labrum is likely to influence impingement, which may also depend on acetabular coverage. Simulating impingement using 3-dimensional (3D) computed tomography (CT) is a potential solution to evaluating range of motion (ROM); however, it is based on bony structures rather than on soft tissue.

Purpose:

To examine ROM when the labrum is considered in a 3D dynamic simulation. A particular focus was evaluation of maximum flexion and internal rotation angles before occurrence of impingement, comparing them in cases of cam-type femoroacetabular impingement (FAI) and borderline developmental dysplasia of the hip (BDDH).

Study Design:

Descriptive laboratory study.

Methods:

Magnetic resonance imaging (MRI) and CT scans of 40 hips (20 with cam-type FAI and 20 with BDDH) were reviewed retrospectively. The thickness and width of the labrum were measured on MRI scans. A virtual labrum was reconstructed based on patient-specific sizes measured on MRI scans. The impingement point was identified using 3D dynamic simulation and was compared with the internal rotation angle before and after labral reconstruction.

Results:

The thickness and width of the labrum were significantly larger in BDDH than in FAI (P < .001). In FAI, the maximum internal rotation angles without the labrum were 30.3° at 90° of flexion and 56.9° at 45° of flexion, with these values decreasing to 18.7° and 41.4°, respectively, after labral reconstruction (P < .001). In BDDH, the maximum internal rotation angles were 48.0° at 90° of flexion and 76.7° at 45° of flexion without the labrum, decreasing to 31.1° and 55.3°, respectively, after labral reconstruction (P < .001). The differences in the angles before and after labral reconstruction were larger in BDDH than in FAI (90° of flexion, P = .03; 45° of flexion, P = .01).

Conclusion:

As the labrum was significantly more hypertrophic in BDDH than in FAI, the virtual labral model revealed that the labrum’s interference with the maximum internal rotation angle was also significantly larger in BDDH.

Clinical Relevance:

The labrum has a significant effect on impingement; this is more significant for BDDH than for FAI.

Femoroacetabular Impingement and Acetabular Labral Tears - Part 1: Pathophysiology and Biomechanics

Femoroacetabular impingement (FAI) is an important cause of hip pain, and the main etiology of hip osteoarthritis in the young population. Femoroacetabular impingement is characterized by subtle alterations in the anatomy of the acetabulum and proximal femur, which can lead to labrum tearing. The acetabular labrum is essential to the stability of the hip joint. Three types of FAI were described: cam (anespherical femoral head), pincer (acetabular overcoverage) and mixed (characteristics of both cam and pincer). The etiology of FAI is related to genetic and environmental characteristics. Knowledge of this condition is essential to adequately treat patients presenting with hip pain.

Comparison of Suction Seal and Contact Pressures Between 270° Labral Reconstruction, Labral Repair, and the Intact Labrum

PURPOSE

To biomechanically compare the suction seal, contact area, contact pressures, and peak forces of the intact native labrum, torn labrum, 12- to 3-o'clock labral repair, and 270° labral reconstruction in the hip.

METHODS

A cadaveric study was performed using 8 fresh-frozen hemipelvises with intact labra and without osteoarthritis. Intra-articular pressure maps were produced for each specimen using an electromechanical testing system under the following conditions: (1) intact labrum, (2) labral tear, (3) labral repair between the 12- and 3-o'clock positions, and (4) 270° labral reconstruction using iliotibial band allograft. Specimens were examined in neutral position, 20° of extension, and 60° of flexion. In each condition, contact pressure, contact area, and peak force were obtained. Repeated-measures analysis of variance was used to identify differences in biomechanical parameters among the 3 conditions. Qualitative differences in suction seal were compared between labral repair and labral reconstruction using the Fisher exact test.

RESULTS

Repeated-measures analysis of variance for contact area in neutral position, extension, and flexion showed statistically significant differences between the normalized study states (P < .05). Post hoc analysis showed significantly larger contact areas measured in labral repair specimens than in labral reconstruction specimens in the extension and flexion positions. Region-of-interest analysis for the normalized contact area in the extension and flexion positions, as well as normalized contact pressures in neutral position, showed statistically significant differences between the labral states (P < .05). Finally, 8 labral repairs (100%) versus only 1 labral reconstruction (12.5%) retained the manually tested suction seal (P < .001).

CONCLUSIONS

In this in vitro biomechanical model, 270° labral reconstruction resulted in decreased intra-articular contact area and loss of suction seal when compared with labral repair. Clinically, labral reconstruction may not restore the biomechanical characteristics of the native labrum as compared with labral repair.

CLINICAL RELEVANCE

Labral reconstruction may result in lower intra-articular hip contact area and loss of suction seal, affecting the native biomechanical function of the acetabular labrum. Further biomechanical studies and clinical studies are necessary to determine whether there are any long-term consequences of 270° labral reconstruction.

All-suture anchors in arthroscopic acetabular labral repair: our experience

Background:

Over the past years, the role of the acetabular labrum in hip joint biomechanics and its relations with joint health has been of particular interest. There is a good clinical improvement of patients in whom the acetabular labrum is preserved during arthroscopic hip surgery. The purpose of this study is to report the results of arthroscopic repair of labral tears at a medium term follow up.

Materials and methods:

We performed a retrospective review of all cases that underwent hip arthroscopy at our Institution from January 2013 until December 2018. There were 24 patients, 13 males and 11 females, and their mean age at the time of surgery was 29, 42 years (range, 19 to 43 years). All patients were treated by the same surgeon with an extracapsular OUT-IN approach. Suture was performed using a non-absorbable suture anchor all-suture. Clinical assessment was performed at December 2019 using a modified Harris hip score (mHHS), hip outcomes score activities of daily living (HOS ADL), hip outcomes score activities of sport scale (HOS SS). All patients with acetabular labrum injury had femoro-acetabular impingement.

Results:

The mean overall values in the preoperative period were 67.21 ± 10.31 for mHHS, 70.04 ± 12.11 for HOS-ADL and 60.06 ± 14.58 for HOS –SS. The results obtained in the re-evaluations of patients in December 2019 with a mean follow-up of 38, 3 months (minimum 1 year) are on average 82.17 ± 11.36 for mHHS, 83.00 ± 12.80 for HOS-ADL and 76.09 ± 18.52 for HOS-SS.

Conclusions:

The progress of knowledge and the advancement of diagnostic and therapeutic skills has led to a greater awareness of the importance of treating acetabular labrum tears. Arthroscopic treatment with suture appear to be a good option for these patients and we had encouraging results in our center. (www.actabiomedica.it)

Validity of Magnetic Resonance Imaging Measurement of Hip Labral Width Compared With Intraoperative Assessment

PURPOSE

To determine if magnetic resonance angiography (MRA) and/or magnetic resonance imaging (MRI) could accurately determine the width of the labrum.

METHODS

Consecutively enrolled patients between the ages of 18 and 65 indicated for hip arthroscopy for femoroacetabular impingement were included between December 2017 and June 2018. Inclusion criteria for preoperative MRIs included: MRI availability in picture archiving and communication system; performance on a 1.5T or 3T MRI or 3T MRA; and adequate quality and lack of labrum ossification. Intraoperative labral width measurements were taken at standardized locations using an established acetabular "clockface" paradigm. Measurement was performed using a calibrated probe. The labral width was defined as the distance from the labrum extended laterally from the acetabular rim. MRI measurements were taken by 2 blinded musculoskeletal fellowship-trained radiologists at the same positions. Measurements were made at the 11:30 o'clock position (indirect rectus) on coronal proton density (PD) sequence, at 3 o'clock position (psoas-U) on axial oblique PD sequence, and at 1:30 (a point halfway between the 2) on sagittal fat-suppressed PD. The surgeons were blinded to the radiologists' measurements and vice versa. Intraoperative and radiographic labral width measurements were compared using an intraclass correlation coefficients (ICC), absolute agreement, and 2-way random effects model. The 2 radiologists' measurements were compared for interrater reliability using the same ICC model.

RESULTS

Fifty-one patients were included (30 females, 26 right hips). Average labrum width at the 3:00, 11:30, and 1:30 o'clock positions by arthroscopic measurement were 5.8 mm (range; standard deviation, 2-8; ±1.4), 6.3 mm (2-10; ±1.5) and 6.0 mm (2-9; ±1.5), and by MRI were 6.3 mm (2-10; ±1.5), 6.7 mm (3-10; ±1.4), and 6.1 mm (2-9; ±1.6), respectively. When including all MRI modalities, ICC agreement between intraoperative assessment, and radiologist assessment at the 3:00 o'clock, 11:30, and point halfway between was 0.82 (P < .001), 0.78 (P < .001), 0.84 (P < .001), respectively. Radiologist interrater ICC agreement at the same points was 0.88 (P < .001), 0.93 (P < .001), and 0.88 (P < .001).

CONCLUSIONS

Strong agreement was found between radiologic and arthroscopic measurement of labrum width when using MRI, suggesting MRI is an accurate way to measure labral width. There was not a significant difference between different MRI modalities. Accurately measuring labral width preoperatively with MRI may aid in surgical decision making.

LEVEL OF EVIDENCE

Level II, diagnostic study.

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.

Can preoperative magnetic resonance arthrography accurately predict intraoperative hip labral thickness?

Objective

There is limited literature investigating the reliability of magnetic resonance-based assessments of labral size. The goal of this study was to validate the reliability of magnetic resonance arthrography-based labral size measurements with intra-operative arthroscopic measurements.

Methods

Patients undergoing hip arthroscopy for femoroacetabular impingement and labral tears were prospectively enrolled. Preoperative magnetic resonance arthrograms were used to determine labral size at the anterior-superior portion (zone 2), mid-superior portion (zone 3), and posterior-superior portion (zone 4). Intra-operative labral widths were measured at the same anatomical zones of the acetabulum using an arthroscopic probe. Mean labral size was determined for each location and a Pearson correlation was used to determine the correlation between imaging-based measurements and intra-operative measurements.

Results

117 patients were enrolled with 70% being female, an average age of 39.1 ± 13.3, and an average body mass index was 26.5 ± 5.4. The average labral sizes based on intraoperative measurements were 6.85 mm in zone 2, 7.45 mm in zone 3, and 7.29 mm in zone 4. The average labral sizes based on MRA were 6.95 mm in zone 2, 7.24 mm in zone 3, and 6.71 mm in zone 4. There was a poor correlation between MRA and intraoperative measurements in zones 2 and 3 (zone 2: R = 0.171, p = 0.065; zone 3: R = 0.335, p = 0.00022) and no correlation in zone 4 (R = -0.22, p = 0.82).

Conclusion

This study demonstrates a poor correlation in labral measurements between magnetic resonance arthrogram imaging and intraoperative measurements, suggesting that this imaging modality may be insufficient in providing accurate measurements of labral size.

Hip Labral Augmentation With Tibialis Anterior Tendon Allograft Using the Knotless Pull-Through Technique

The importance of the labrum in the biomechanics of the hip joint is well documented. Labral tears are the most common pathology in patients undergoing hip arthroscopy and therefore appropriate labral management is vital. Labral preservation has been advocated as a superior alternative to labral excision in terms of clinical outcomes. While reconstruction of the labrum is recommended for irreparable tears, labral augmentation is a viable alternative for labral function restoration under certain indications. This Technical Note will describe a method for arthroscopic hip labral augmentation using an anterior tibialis tendon allograft and the pull-through technique.

Primary labral reconstruction in patients with femoroacetabular impingement, irreparable labral tears and severe acetabular chondral defects decreases the risk of conversion to total hip arthroplasty: a pair-matched study

In the presence of severe acetabular cartilage defects, the benefits of labral reconstruction (RECON) versus labral resection (RESEC) have not been determined. Prospectively collected data between October 2008 and December 2016 were retrospectively reviewed. Inclusion criteria were hip arthroscopy, acetabular Outerbridge grade III/IV, irreparable labral tears that underwent RECON or RESEC, and minimum 2-year postoperative measures for the modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, International Hip Outcome Tool, Patient Satisfaction and Visual Analogue Scale for pain. Exclusion criteria included Tönnis grade >1, previous hip conditions or previous ipsilateral hip surgeries. A 1:1 matched-pair analysis was performed based on age ±5 years, sex, body mass index ±5 kg/m², Tönnis grade, acetabular microfracture, femoral Outerbridge grade (0 or I compared with II, III or IV). Relative risk (RR) and conversion rate to total hip arthroplasty (THA) were calculated. A total of 38 RECON hips were successfully matched. Both groups demonstrated significant improvements in patient-reported outcomes (PROs). THA conversion was 5.3% and 21.1% for the RECON and RESEC groups, respectively (P = 0.04). RECON was four times less likely to require THA conversion than the RESEC group (RR=4.0; 95% CI 0.91-17.63). In the setting of primary arthroscopic management of femoroacetabular impingement, irreparable labral tears and acetabular chondral lesions of Outerbridge III/IV, patients that underwent RECON and RESEC experienced significant improvement in PROs at minimum 2-year follow-up, and these functional scores were comparable when groups were matched. However, RR and rate to THA conversion were significantly higher in the RESEC group.

The outcome of arthroscopic repair of acetabular labral tears using the iHOT-33

Background

The purpose of this study was to determine patient reported outcome measures (PROMS) after arthroscopic repair of an isolated labral tear using the validated International Hip Outcome Tool (iHOT-33). The iHOT-33 specifically measures (1) symptoms and functional limitations, (2) sport and recreation limitations, (3) job related concerns and social and (4) emotional and lifestyle concerns.

Methods

A retrospective review was performed on 45 procedures in 43 patients between September 2012 and September 2015. Two patients had bilateral isolated labral tears. Patients were excluded if they were younger than 18 years, had prior ipsilateral hip surgery and had radiological or arthroscopic evidence of femoroacetabular impingement (FAI), hip dysplasia or other bony dysmorphism.

Results

Of the 43 patients undergoing arthroscopy there were 29 right and 16 left hips repaired. There were 34 females and 9 males. The mean age at surgery was 37.4 years (range 19–63 years) with a mean follow up of 1.7 years (range 1.0–2.6 years). At follow up the mean total iHOT-33 score improved from 34.1 to 67.3 (p < 0.02). The mean improvement was 33.2 (p = < 0.02). Significant improvements were described in all 4 iHOT-33 sub sections.

Conclusion

The study showed statistically significant favourable outcomes in selected patients with short follow-up for patients that underwent hip arthroscopy for an isolated labral tear using the validated iHOT-33.

Level of Evidence

IV, retrospective non-randomised study.

Preserving the chondrolabral junction reduces the rate of capsular adhesions

The operative treatment of pincer-type femoroacetabular impingement (FAI) has become an increasingly more common procedure. Classically, the labrum is incised at the chondrolabral junction (CLJ), or a concurrent tear is extended to allow access to the acetabular rim facilitating acetabuloplasty. The labrum is subsequently repaired using suture anchors. More recently, acetabuloplasty has been performed without incising the labrum and negating the need to use suture anchors. The aim of this study is to determine whether preserving the CLJ reduces the incidence of revision hip arthroscopy for the treatment of capsulolabral adhesions. This retrospective study compared two cohorts of patients undergoing hip arthroscopy for pincer-type FAI from August 2002 to April 2015. The groups analysed were patients undergoing acetabuloplasty with labral repair (LR) and those with no labral repair (NLR). The revision rates and causes for revision were compared using the χ² analysis. There were 1010 cases in total. Acetabuloplasty with LR was performed in 546 hips (519 patients), while acetabuloplasty with NLR was performed in 464 hips (431 patients). In the LR group, there were 54 (9.9%) revisions, 25 (46%) of which were due to capsulolabral adhesions. The NLR group had 36 (7.8%) revisions with six (17%) due to capsulolabral adhesions. Preserving the CLJ, thereby avoiding the need for drilling and the insertion of suture anchors, when performing an acetabuloplasty for pincer-type FAI, significantly reduces the rate of symptomatic adhesions requiring revision arthroscopy.

Influence of Acetabular Labral Tear Length on Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome With Capsular Plication

BACKGROUND

The literature on the effects of labral tear on patient-reported outcomes, midterm pain, and overall patient satisfaction is limited.

PURPOSE

To determine the effect of labral tear length on postoperative outcomes after hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Consecutive patients undergoing primary hip arthroscopy for FAIS from January 2012 to January 2016 were identified in a prospectively collected database. All patients completed the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), and visual analog scale for pain and satisfaction. Patients were stratified by labral tear length into small (<2.5 cm) or large (≥2.5 cm) based on the receiver operating characteristic curve analysis. Patient characteristics and outcomes were analyzed with multivariate linear regression analyses to identify predictors of labral tear length. Binary logistic regression analysis was performed to determine whether labral tear length predicted the likelihood of achieving the minimal clinically important difference.

RESULTS

Of the 747 eligible patients, 600 (80.3%) had 2-year reported outcomes and were included in the final analysis. Mean age, body mass index, and tear length were 33.5 ± 12.3 years, 25.4 ± 9.2 kg/m², and 2.7 ± 0.7 cm, respectively. Men had higher frequency of large tears when compared with women (77% vs 43.7%, P < .001). Independent t test demonstrated significant differences in 2-year outcomes between patients with tears <2.5 and ≥2.5 cm, respectively: HOS-ADL (87.3 ± 16.3 vs 84.3 ± 18.1, P = .033), HOS-SS (76.6 ± 23.5 vs 70.5 ± 27.7, P = .005), mHHS (82.5 ± 18.0 vs 78.5 ± 18.2, P = .009), and satisfaction (83.5 ± 23.4 vs 77.8 ± 34.9, P = .026). Binary logistic regression analysis demonstrated that labral tear length is an independent predictor of visual analog scale for satisfaction, HOS-ADL, HOS-SS, and mHHS. Binary logistic regression analysis demonstrated that patients with small labral tears had a higher likelihood of achieving the minimal clinically important difference for the HOS-SS (odds ratio, 1.61; 95% CI, 1.39-1.92; P < .02) and the patient acceptable symptomatic state for the mHHS (odds ratio, 1.56; 95% CI, 1.11-2.2; P = .038) than those with larger tears.

CONCLUSION

Labral tear length is independently predictive of patient-reported outcomes after hip arthroscopy for FAIS. Furthermore, patients with smaller tears (<2.5 cm) had better outcomes and a higher likelihood of achieving a minimal clinically important difference at 2-year follow-up. However, the mean differences between changes in pre- and postoperative outcomes were relatively small and may not be clinically meaningful.

Mechanical and Cytocompatibility Evaluation of UHMWPE/PCL/Bioglass® Fibrous Composite for Acetabular Labrum Implant

In this study, a fibrous composite was developed as synthetic graft for labral reconstruction treatment, comprised of ultra-high molecular weight polyethylene (UHMWPE) fabric, ultrafine fibre of polycaprolactone (PCL), and 45S5 Bioglass®. This experiment aimed to examine the mechanical performance and cytocompatibility of the composite. Electrospinning and a slurry dipping technique were applied for composite fabrication. To assess the mechanical performance of UHMWPE, tensile cyclic loading test was carried out. Meanwhile, cytocompatibility of the composite on fibroblastic cells was examined through a viability assay, as well as SEM images to observe cell attachment and proliferation. The mechanical test showed that the UHMWPE fabric had a mean displacement of 1.038 mm after 600 cycles, approximately 4.5 times greater resistance compared to that of natural labrum, based on data obtained from literature. A viability assay demonstrated the predominant occupation of live cells on the material surface, suggesting that the composite was able to provide a viable environment for cell growth. Meanwhile, SEM images exhibited cell adhesion and the formation of cell colonies on the material surface. These results indicated that the UHMWPE/PCL/Bioglass® composite could be a promising material for labrum implants.

Hip labral reconstruction: consensus study on indications, graft type and technique among high-volume surgeons

To survey high-volume hip arthroscopists regarding their current indications for labral reconstruction, graft preference and technique. In May 2018, a cross-sectional based survey was conducted on high-volume hip arthroscopists. A high-volume surgeon was defined as an orthopaedist who had case experience ranging from 50 to 5000 hip arthroscopies performed annually. The survey included their current indications for labral reconstruction, graft preference and technique. Twelve high-volume surgeons successfully completed the questionnaire. The mean arthroscopic procedures performed by the surgeons annually was 188.7 (range 60–350). Four surgeons (33.3%) performed <5 labral reconstruction cases per year, three (25.0%) 5–10 cases per year, two (16.7%) 11–15 cases per year and three (25.0%) over 20 cases per year. Of the 12 surgeons, 11 (91.6%) would reconstruct in certain primary settings and 100% would reconstruct in revision settings. In the primary setting, the main indications for reconstruction were poor quality labral tissue, calcified labrum and hypoplastic labrum. None of the surgeons recommended labral reconstruction for reparable labral tears in primary cases. In primary cases of irreparable labra, 58.3% of the surgeons favoured reconstruction over debridement. In revisions, 100% of the surgeon favoured reconstruction over debridement; 91.7% chose an allograft option versus an autograft alternative. Amongst high-volume arthroscopists, labral reconstruction was considered a valuable technique to restore labral function. Labral reconstruction was more often advocated in revision than in primary settings. Allograft was the preferred choice for reconstruction. Excision of the labral tissue prior to reconstruction was favoured over augmentation. Fewer surgeons performed circumferential reconstruction than segmental reconstruction.