The ligamentum teres-its increasing importance

The Effects of Arthroscopic Labral Repair on Patient-Reported Outcomes in the Setting of Periacetabular Osteotomy

BACKGROUND

It is currently unknown whether the addition of arthroscopic labral repair in the setting of periacetabular osteotomy (PAO) provides any clinical benefit.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare outcomes of patients who underwent arthroscopic labral repair concomitantly with PAO versus patients who underwent PAO alone. We hypothesized that there would be no difference in patient-reported outcome measures (PROMs) between the cohorts.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing PAO from a single-center prospective hip preservation registry were eligible for this study if they completed pre- and postoperative PROMs (minimum, 1 year). PROMs were collected at 1 year, 2 years, and latest follow-up at 6.05 years for PAO group and 4.2 years for scope/PAO group. The study group consisted of 53 patients who underwent arthroscopic labral repair at the time of their PAO, and the comparison group consisted of 170 patients who underwent PAO alone. A subset of the PAO group who had radiologic evidence of a detached labral tear (n = 33) was also compared with the rest of the PAO-alone group. PROMs were compared at every time point for both groups as well as the subset of patients who underwent PAO alone despite a labral tear.

RESULTS

The mean follow-up of all patients was 2 years (range, 1-6 years). Overall, 85.2% of the PAO group and 85.7% of the scope/PAO group met the minimal clinically important difference for either the modified Harris Hip Score (mHHS) or the International Hip Outcome Tool (iHOT-33) at the most recent follow-up. There was no difference in improvement between groups (mHHS, P = .670; iHOT-33, P = .944). Patients who had a radiologically diagnosed detached labral tear and underwent PAO alone had no difference in outcomes when compared with the rest of the PAO cohort (mHHS, P = .981; iHOT-33, P = .909).

CONCLUSION

There was no significant benefit measured by PROMs at follow-up for concomitant arthroscopic labral repair in the setting of PAO.

Combined 3-Dimensional CT and Multidirectional CT Arthrography for Femoroacetabular Impingement and Hip Lesions: A Cross-sectional Study Comparing Imaging and Hip Arthroscopic Surgery Findings

Background

There is limited research investigating the diagnostic strength of 3-dimensional computed tomography (3D-CT) and multidirectional CT arthrography (CTA) for femoroacetabular impingement (FAI) and related hip lesions.

Purpose

To evaluate the diagnostic strength of combined 3D-CT and CTA in patients with FAI and related hip lesions by comparing it with hip arthroscopic surgery findings.

Study Design

Cohort study (diagnosis); Level of evidence, 2.

Methods

This study included patients who were suspected of having FAI and related hip lesions and who underwent a combination of 3D-CT and CTA and subsequent hip arthroscopic surgery between December 2013 and December 2017. The CT and intraoperative arthroscopic findings were recorded and compared. The sensitivity, specificity, and accuracy of 3D-CT for FAI and those of CTA for related hip lesions were calculated.

Results

A total of 114 patients with 114 hips were included in our study. There were 101 patients with positive findings and 13 patients with negative findings for FAI (including cam, pincer, and combined morphology) according to 3D-CT. The sensitivity, specificity, and accuracy of 3D-CT for FAI were 91.58%, 57.14%, and 89.47%, respectively. The sensitivity, specificity, and accuracy of CTA for labral tears were 94.64%, 100.00%, and 94.73%, respectively. For acetabular cartilage defects, the sensitivity, specificity, and accuracy of CTA were 60.71%, 91.37%, and 76.31%, respectively. For femoral cartilage defects, the sensitivity, specificity, and accuracy of CTA were 82.22%, 76.81%, and 78.94%, respectively.

Conclusion

The study results indicated that 3D-CT was able to provide excellent accuracy for FAI compared with hip arthroscopic surgery findings. In addition, multidirectional CTA demonstrated promising diagnostic strength for hip lesions such as labral tears and chondral defects.

Ligamentum teres reconstruction using autogenous semitendinosus tendon with toggle technique in rabbits

Background

Ligamentum teres (LT) has traditionally been considered a vestigial or redundant structure in humans; however, based on new studies and the evolution of hip arthroscopy, the LT injury has been viewed as a source of hip pain. Therefore, LT reconstruction can be beneficial in some cases. Rabbits have been frequently used as a model for cranial cruciate ligament reconstruction but few studies are available for ligamentum teres reconstruction.

Objective

To evaluate the semitendinosus tendon to replace ligamentum teres with the toggle technique, using rabbits as an experimental model.

Methods

Twenty-six female Norfolk rabbits with approximately 3 months of age were divided into two equal groups after excision of ligamentum teres (LT) from the right hip joint: G1-no reconstruction of LT and capsulorrhaphy; G2-double-bundle reconstruction of the LT using semitendinosus tendon autograft. In both groups, the LT was removed from the right hip joint. In G2 the autograft was harvested from the left hind limb of the same rabbit. The rabbits were evaluated clinically at different time intervals; before surgery (M1), 48 h (M2), 15 days (M3), 30 days (M4) and 90 days (M5) after surgery.

Results

The rabbits supported their limbs on the ground in both the groups. As complications of the procedure, four hip joints showed subluxations in the radiographic evaluation of G1; three at M4 and one at M5. In G2; two luxations of hip joints at M3 and one subluxation at M4 were seen. On ultrasound, irregular articular surface was seen in 30.8% of the rabbits that had subluxation of hip joints. Gross evaluation identified tendon graft integrity in 76.92% of the rabbits. Histological analysis revealed graft adhesion to the bone in the early phase comprised of sharpey-like collagen fibers.

Conclusion

The double-bundle reconstruction of the LT using autologous semitendinosus tendon associated with the toggle rod shows an early phase of tendon graft ligamentization at 90 days post-operatively in young rabbits, but biomechanical bias suffered by the tendon during gait must be considered.

Reliability and Reproducibility of a Novel Grading System for Lesions of the Ligamentous-Fossa-Foveolar Complex in Young Patients Undergoing Open Hip Preservation Surgery

Background:

Several classification systems based on arthroscopy have been used to describe lesions of the ligamentum teres (LT) in young active patients undergoing hip-preserving surgery. Inspection of the LT and associated lesions of the adjuvant fovea capitis and acetabular fossa is limited when done arthroscopically but is much more thorough during open surgical hip dislocation. Therefore, we propose a novel grading system based on our findings during surgical dislocation comprising the full spectrum of ligamentous-fossa-foveolar complex (LFFC) lesions.

Purpose:

To determine (1) intraobserver reliability and (2) interobserver reproducibility of our new grading system.

Study Design:

Cohort study (diagnosis); Level of evidence, 3.

Methods:

We performed this validation study on 211 hips (633 images in total) with surgical hip dislocation (2013-2021). We randomly selected 5 images per grade for each LFFC item to achieve an equal representation of all grades (resulting in 75 images). The ligament, fossa, and fovea were subcategorized into normal, inflammation, degeneration, partial, and complete defects. All surgeries were performed in a standardized way by a single surgeon. The femur was disarticulated using a bone hook, the LT was inspected, documented and resected, then the fossa and fovea were documented with the femoral head in full dislocation using a 70° arthroscope. Six observers with different levels of expertise in hip-preserving surgery independently conducted the measurements twice, and intraclass correlation coefficients (ICC) were calculated to determine (1) intraobserver reliability and (2) interobserver reproducibility of the novel grading system.

Results:

For intraobserver reliability, excellent ICCs were found in both the junior and the experienced raters for grading the ligament, fossa, fovea, and total LFFC (ICCs ranged from 0.91 to 0.99 for the LFFC score). We found excellent interobserver reproducibility between raters for all items of the LFFC (all interobserver ICCs ≥ 0.76).

Conclusion:

Our new grading system for lesions of the LFFC is highly reliable and reproducible. It covers the full spectrum of damage more precisely than arthroscopic classifications do and offers a scientific basis for standardized intraoperative evaluation.

THE ROUND LIGAMENT IN DEVELOPMENTAL HIP DYSPLASIA: ARE ITS MECHANICAL AND HISTOLOGICAL PROPERTIES PRESERVED?

Introduction

During open surgical dislocated hip reduction, several anatomical structures, such as the round ligament, are approached. However, there is controversy over both the possibility of preserving the ligament and its functional importance.

Materials and Methods

This experimental study used skeletally immature rabbits as a model for congenital hip dislocation. Thirty-six rabbits comprised the sample that was submitted to the round ligament analysis. The sample was stratified for analysis (biomechanics, zymography, histology, and immunohistochemistry). Statistical analysis compared the unstable side to the control side of each rabbit.

Results

Biomechanical assays showed that the mean maximal strength of the round ligament on the unstable side was similar to that of the control side (p = 0.594), which was also the case with maximum deformation (p = 0.328). Histologically, there was a statistically significant increase in cellularity on the unstable side (p <0.001). Additionally, there was significantly greater collagen occupancy on the control side (p <0.001). Zymography revealed no significant difference in the amount of active metalloproteinase 2 (MMP-2) (p = 0.068).

Conclusions

Although histological analysis found evidence of significant changes in the RL in unstable hips, there were no significant differences in zymography, and no changes were observed in biomechanical tests. Evidence Level V; Experimental study.

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.

The role and clinical relevance of the ligamentum teres: long-term outcomes after hip arthroscopic surgery of cam-type femoroacetabular impingement

We aimed to compare clinical and radiologic outcomes in patients with cam-type femoroacetabular impingement (FAI), with and without a partial ligamentum teres (LT) tear, who underwent hip arthroscopy (HA) with ≥10 years of follow-up. Among the patients who underwent HA for a cam-type FAI diagnosis with a labral tear, 28 patients (28 hips) with a partial LT tear and 87 patients (99 hips) with an intact LT were assigned to Groups A and B, respectively. All patients underwent partial labral debridement and femoroplasty. Debridement and thermal shrinkage were performed for LT tears. The grade of chondral damage was measured intraoperatively. Clinical items were assessed preoperatively and at the last follow-up. Patients’ satisfaction with the surgery and changes in postoperative sports ability in those who had previously been active in sports were assessed at the last follow-up. The Tönnis grade was assessed preoperatively and at the last follow-up for radiologic evaluation. Chondral damage to the acetabular and femoral head detected intraoperatively was significantly different between the groups (P = 0.005 and P &lt; 0.001). At the last follow-up, Group A patients experienced more difficulty performing sports activities than Group B patients (P = 0.056), and significantly, more Group A patients had stopped exercising despite their active participation in sports preoperatively (P = 0.002). Regarding the Tönnis grade, significant differences were found only at the final follow-up (P = 0.020). Patients with partial LT tear showed a higher grade of chondral damage, experienced decreased exercise capacity and had significantly worsened Tönnis grades, suggesting hip osteoarthritis progression compared to those with an intact LT.

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

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

All About the Ligamentum Teres: From Biomechanical Role to Surgical Reconstruction

Intriguing anatomists and surgeons for centuries, the exact function and biomechanical significance of the ligamentum teres (LT) remains incompletely understood. The LT, also described as the ligamentum femoris capitis, is an intra-articular extrasynovial ligament extending from the cotyloid fossa of the acetabulum to the fovea on the femoral head. Some studies have described it as a vestigial structure in the adult hip. More recent biomechanical studies, however, along with histological and anatomical studies, have suggested the LT to have an important function in proprioception, nociception, and as a secondary stabilizer of the hip joint. The advent and increased utilization of hip arthroscopy to treat hip pathology over the past two decades has ignited a renewed interest in the role of the LT, as well as techniques and indications for management of pathology. In the constellation of intra-articular pain generators of the hip, LT injuries have historically been difficult to diagnose through physical examination or advanced imaging. Numerous classification systems have been proposed based on arthroscopic appearance, and for most cases, conservative management is adequate. In patients undergoing hip arthroscopy, LT débridement usually suffices, although in cases of persistent pain and severe instability, reconstruction of the ligament may be indicated. Multiple methods for reconstruction have been described, with the greatest variation in the method of acetabular fixation of the graft. Future research should focus on clarifying the role of the LT, appropriate surgical indications for reconstruction, and optimization of graft fixation within the acetabulum.

An Intact Ligamentum Teres Predicts a Superior Prognosis in Patients With Borderline Dysplasia: A Matched-Pair Controlled Study With Minimum 5-Year Outcomes After Hip Arthroscopic Surgery

BACKGROUND

Hip arthroscopic surgery in patients with borderline dysplasia continues to be controversial. In addition, it has been suggested that ligamentum teres (LT) tears may lead to inferior short-term patient-reported outcomes (PROs) when compared with a match-controlled group.

PURPOSES

(1) To report minimum 5-year PROs in patients with borderline dysplasia and LT tears who underwent hip arthroscopic surgery and (2) to compare these PROs to those of a matched-pair control group of patients with borderline dysplastic hips without LT tears.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected for patients who underwent hip arthroscopic surgery between September 2008 and August 2013. Patients were included if they had a preoperative diagnosis of borderline dysplasia (lateral center-edge angle [LCEA], 18°-25°) and had preoperative and minimum 5-year postoperative modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), and visual analog scale (VAS) for pain scores. Exclusion criteria were osteoarthritis of Tönnis grade >1, previous hip conditions, any previous ipsilateral hip surgery, or workers' compensation status. There were 2 borderline dysplastic groups created. An LT tear group was matched 1:1 to a control group (no LT tear) with similar age, sex, body mass index (BMI), and laterality via propensity score matching. Significance was set at P < .05.

RESULTS

A total of 24 patients with an LT tear (24 hips) were matched to 24 patients without an LT tear (24 hips). There was no significant difference in age, sex, BMI, or laterality between groups. The mean age was 36.2 ± 17.2 and 34.9 ± 15.9 years for the control and LT tear groups, respectively (P = .783). There were 17 (70.8%) and 16 (66.7%) female patients in the control and LT tear groups, respectively, and the mean preoperative LCEA was 23.3° and 22.2° in the control and LT tear groups, respectively. No differences were observed between groups in baseline PROs, intraoperative findings, or surgical procedures. LT debridement was performed in 17 (70.8%) patients in the LT tear group compared with 0 (0.0%) in the control group. Also, 5-year postoperative PROs were comparable in both groups, with the control group exhibiting superior Veterans RAND 12-Item Health Survey (VR-12) mental (P = .041) and Short Form-12 (SF-12) mental (P = .042) scores. Finally, hips with an intact LT were significantly more likely (P = .022) to achieve the patient acceptable symptomatic state (PASS) for the mHHS (100.0% and 75.0%, respectively). No significant differences were present between the groups for the minimal clinically important difference (MCID) of the mHHS (P = .140), MCID of the Hip Outcome Score-Sport-Specific Subscale (HOS-SSS) (P = .550), or PASS of the HOS-SSS (P = .390).

CONCLUSION

After hip arthroscopic surgery, patients with borderline dysplasia and LT tears demonstrated favorable PROs at a minimum 5-year follow-up. Outcomes were similar to a matched-pair control group without LT tears, with the group with intact LTs showing higher VR-12 mental and SF-12 mental scores. Furthermore, patients with borderline dysplasia and intact LTs were significantly more likely to achieve the PASS for the mHHS.

Ligamentum teres reconstruction: indications, technique and minimum 1-year results in nine patients

Ligamentum teres (LT) tear is a recognized cause of hip pain. Debridement of tears and capsule plication has shown satisfactory results. However, a group of patients with complete tears do not improve after debridement and physiotherapy. The purpose of this work was to describe the senior author's technique and clinical results for the early series of LT reconstructions. Retrospective analysis of prospectively collected data. Patients who underwent isolated LT reconstruction between 2013 and 2018. All the patients had previous debridement of a completely torn LT, capsule plication and rehabilitation. Patients who had any other associated procedure during LT reconstruction surgery and dysplastic acetabular features were excluded. Demographic and clinical data was reviewed. Complications, type of graft and modified Harris hip scores (mHHSs) were recorded preoperatively and at 1-year follow-up. Fifteen LT reconstructions were performed during the study period. Six were excluded (as they had additional procedures performed during surgery) and nine patients aged a mean 30 (range: 22-48) years old were included. The patients had a mean of 2 (range: 1-4) prior surgeries. At minimum 12 months (range: 12-24) 9/9 patients reported reduction of pain and instability symptoms with mHHSs of 84.2 (73.7-100) versus 51.7 (36.3-70.4) preoperatively (P = 0.00094). Three patients (of the total cohort of 15) underwent second-look arthroscopy (11-22 months after reconstruction). None of these patients underwent total hip replacement at a mean of 4 (range: 1-6) years. Arthroscopic LT reconstruction improved function and pain in patients with persistent pain and instability after resection of the LT.

Do Larger Acetabular Chondral Defects Portend Inferior Outcomes in Patients Undergoing Arthroscopic Acetabular Microfracture? A Matched-Controlled Study

PURPOSE

To elucidate the effect, if any, of acetabular chondral defect size on surgical outcomes after arthroscopic microfracture was performed with concomitant treatment for labral tears and femoroacetabular impingement (FAI) syndrome.

METHODS

The study period was between February 2008 and November 2014. Data were collected on patients who underwent hip arthroscopy. The inclusion criteria were acetabular microfracture; concomitant treatment for labral tears and FAI syndrome; and preoperative modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, and visual analog scale. Exclusion criteria were Workers' Compensation, preoperative Tönnis grade >1, or previous ipsilateral hip surgeries or conditions. Patients were grouped based on smaller chondral defects (SCDs) or larger chondral defects (LCDs), then matched 1:1 by age at surgery ±10 years, sex, body mass index ±5, labral treatment, capsular treatment, acetabuloplasty, and femoroplasty. Outcomes, secondary arthroscopies, and conversions to total hip arthroplasty (THA) were documented.

RESULTS

Of 131 eligible cases, 107 (81.7%) had minimum 2-year follow-up. Before matching, the conversion rate to THA was higher for LCDs (24.6%) than for SCDs (12.0%). Thirty-five patients were matched for each group. Mean follow-up time was 47.9 months (range, 24.0, 84.1) for the matched LCD group and 46.1 months (range, 24.0, 88.1) for the matched SCD group. Ligamentum teres debridement (P = .03) was performed more frequently in the LCD group. No other differences were found regarding demographics, intraoperative findings, procedures, traction time, preoperative scores, or follow-up scores. Both groups demonstrated significant improvements in all scores. Rates of revision or conversion to THA were similar between groups. The relative risk for conversion to THA was 2.33 for patients with defects ≥300 mm² compared with patients with defects ≤250 mm² (P = .13). Deep vein thrombosis occurred in 3 (5.3%) patients with LCDs.

CONCLUSIONS

Matched patients with either SCDs or LCDs undergoing arthroscopic acetabular microfracture with concomitant treatment for labral tears and FAI syndrome demonstrated similar improvements at minimum 2-year follow-up. Patients with chondral defects approaching 300 mm² or greater may have a higher propensity toward conversion to THA.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Non-traumatic ligamentum teres tears: association with MRI morphometry of the hip

BACKGROUND

The ligamentum teres has been recognized as an important stabilizer of the hip.

PURPOSE

We aimed to examine the relationship between non-traumatic ligamentum teres (LT) tear and hip morphometry on magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Fifty patients who had undergone hip MRI were included (27 men, 23 women; average age = 54.0 years). The status of the LT and the morphometric hip parameters were assessed, including acetabular anteversion angle (AAA), acetabular depth (AD), acetabular index (AI), lateral center edge angle (LCEA), and extrusion index (EI). The morphometric hip parameters were compared between groups with one-way ANOVA, Student's t-test, and Mann-Whitney U test.

RESULTS

A decreased acetabular coverage was noted in the severe tear group compared to the normal group, indicated by a significantly larger AD ( P = 0.001) and smaller LCEA ( P = 0.016). There was a statistically significant difference in the AAA, AD, and LCEA between the normal group and the complete tear group; the AAA was significantly larger ( P = 0.031), the AD was significantly larger ( P = 0.01), and the LCEA was significantly smaller ( P = 0.043) in the complete tear group compared to the normal group.

CONCLUSION

There is an association between LT tears and acetabular bony morphology; an insufficient acetabular coverage is associated with complete tear of the LT. As the insufficient acetabular coverage may predispose to ligamentum teres tear, the ligamentum teres should be thoroughly evaluated in those with insufficient acetabular coverage, as a potential cause of hip pain.

Neurovascular structures of the ligament of the head of femur

The ligament of the head of femur (LHF), or ligamentum teres, is believed to provide blood supply to the head of femur and mechanical stability to the hip joint. But these functions in the adult are often debated. The existence and distribution of neurovascular structures within the ligament are not widely documented. This study examined the blood vessels and nervous tissue within the LHF to determine whether the ligament may have a vascular and proprioceptive function at the hip joint. Histological sections from the LHF from 10 embalmed hips (six female, four male; mean age 80.4 ± 8.7 years) were cut at three levels: the foveal attachment, mid-length and its base where it attaches to the transverse acetabular ligament. Sections were stained with haematoxylin and eosin to study general tissue architecture or with von Willebrand factor and neurofilament to identify blood vessels and nervous tissue, respectively. The proportion of the ligament's cross-sectional area occupied by blood vessels was expressed as a vascularity index (VI). Nerve endings within the ligament were identified and morphologically classified. Comparisons between the VI at the three levels, or between the tissue layers of the ligament, were made using 95% confidence intervals; statistical significance was set P < 0.05. The ligament tissue comprised three distinct layers: a synovial lining with cuboidal cells, a sub-synovial zone formed of loose connective tissue and the ligament proper composed of dense collagen bundles. Patent blood vessels and nerve fibres were present both in the sub-synovial zone and the ligament proper; Pacinian corpuscles and free nerve endings were found scattered only in the sub-synovial zone. The VI of the ligament proper at the fovea was significantly higher than its middle (P = 0.01) and basal levels (P = 0.04); it was also higher than that of the sub-synovial layer (P = 0.04). The LHF has three histologically distinct zones, and blood vessels and nerves are distributed both in the sub-synovial layer and ligament proper. Higher vascularity within the ligament proper at its foveal insertion suggests a possible nutritive role of the LHF to the adult head of femur. The presence of nerves and nerve receptors indicates the ligament is involved in the perception of pain and proprioception, thereby contributing to mechanical stability of the joint.

The Effect of Complete Tearing of the Ligamentum Teres in Patients Undergoing Primary Hip Arthroscopy for Femoroacetabular Impingement and Labral Tears: A Match-Controlled Study

PURPOSE

To compare the patient-reported outcomes scores (PROs) of patients with femoroacetabular impingement (FAI), labral tears, and complete ligamentum teres (LT) tears to a matched-pair control group with intact LTs, as well as to report the relative risk of total hip arthroplasty (THA) conversion.

METHODS

Data between February 2008 and April 2015 were retrospectively reviewed. Patients undergoing hip arthroscopy included those who had complete LT tear, labral tears, FAI, and minimum 2-year follow-up with modified Harris Hip Score (mHHS), Non-arthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scale (VAS). Patients were excluded for Tönnis osteoarthritis grade >1, previous hip conditions or surgeries, and Worker's Compensation claims. Patients with full LT tears were matched in a 1:3 ratio with patients without LT tears based on age at surgery ± 5 years, sex, body mass index ± 5, capsular treatment, and acetabular Outerbridge grade. Revision surgeries and conversions to THA were documented. Relative risk for conversion to THA was determined (P = .05).

RESULTS

Eighteen patients (18 hips) had minimum 2-year follow-up and were eligible for matching; as described, each study group patient was matched to 3 control patients, resulting in a size of 18 to 54 patients. PROs showed significant improvement in the complete LT tear group with the exception of the HOS-SSS measure. In the intact LT control group, all PROs significantly improved, with no exception. Based on relative risk, patients with complete LT tears were 3 times more likely to require THA than a matched control group.

CONCLUSIONS

After hip arthroscopy, patients with FAI and complete LT tears reported significant improvement in PROs. Among hips that did not require THA, functional scores were comparable to a matched control group. However, patients with complete LT tears were 3 times more likely to require an eventual THA than the matched control group. We conclude that patients with complete LT tears should be considered an at-risk population, and that indications and treatment may be refined to incorporate the clinical significance of complete LT tears.

LEVEL OF EVIDENCE

Level III, comparative trial, case-control.

Editorial Commentary: Chicken or the Egg? The Ligamentum Teres and Degenerative Hip Disease

The ligamentum teres has traditionally been described as a vestigial remnant or redundant structure with little contribution to hip biomechanics or function. However, interest in the ligamentum teres has been renewed as evidence has emerged that it not only plays a role as a pain generator in the hip but also acts as a secondary stabilizer to supplement the work of the capsular ligaments. Furthermore, an association has been proposed between tearing of the ligamentum teres and the development of degenerative hip disease. However, the question remains, is it a cause-and-effect relationship?

The position and morphometry of the fovea capitis femoris in computed tomography of the hip

Purpose

The position of the fovea of the femoral head is usually considered to be inferior or inferoposterior, despite the fact that few detailed anatomical studies have been performed. This study was performed to assess the position of the fovea in computed tomography and its correlation with standard radiographic measures of the proximal femur.

Methods

Computed tomography scans of the hip of 107 patients (54 women and 53 men) were evaluated. The semi-coronal and transverse views were used to assess the femoral neck–shaft angle and the neck version, as well as the size and position of the fovea in relation with the femoral neck axis and the size of the head.

Results

The fovea was always located inferior to the neck axis in the semi-coronal plane. In the transverse plane, the fovea was always slightly posterior to the femoral neck axis, as approximately ¾ of its diameter was posterior to the axis. The position was unrelated to the neck–shaft axis and the neck–trochanter minor angle. There were no differences in the position between men and women; however, in women, the fovea is slightly larger than in men when related to the femoral head size.

Conclusion

The femoral neck axis in the transverse plane always crosses the anterior aspect of the fovea. Its position is unrelated to the angular geometry of the proximal femur, but related to the femoral head size. It is found to be relatively larger in women.

Posterior Bony Impingement-Potential Mechanism of Ligamentum Teres Tears

PURPOSE

To describe a potential causal mechanism of ligamentum teres (LT) tears, a specific treatment for posterior impingement of the LT, and to report the minimum 2-year outcome of this treatment.

METHODS

We retrospectively reviewed data collected from 1,251 hip arthroscopies performed by the senior surgeon over a 26-month period. During this time, 424 LT tears were identified including 9 patients with isolated partial LT tears caused by impingement of the LT against a prominent acetabular fossa posterior wall and no other intra-articular pathology. All 9 patients were treated with LT tear debridement and excision of the impinging bony prominence using an arthroscopic burr. Patients were followed with a modified Harris hip score and nonarthritic hip score for a minimum of 24 months (mean, 29 months; range, 24-38 months).

RESULTS

After surgery, all patients returned to their preinjury level of activity. The modified Harris hip score increased from a mean of 58.9 preoperatively (range, 41.8-84.7) to 89.2 (range, 70.3.5-96.7) (P = .02) at a minimum of 2-year follow-up. Similarly, the nonarthritic hip score increased from a mean of 56.2 (range, 35-90) to 91.9 (range, 81.5-98.5) (P = .01) at a minimum of 2 years after surgery. There were no complications associated with the procedure and no revision surgeries performed over the 2-year follow-up.

CONCLUSIONS

LT tears may, very uncommonly, be caused by impingement of the mid-part of the ligament against a prominent posterior acetabular fossa edge. In this group of 9 cases, debridement of the torn ligament segment, in combination with resection of the impinging bone, was associated with marked symptomatic improvement and full return to activities for a minimum of 2 years.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Contribution of the Ligamentum Teres to Hip Stability in the Presence of an Intact Capsule: A Cadaveric Study

PURPOSE

To determine the contribution of the ligamentum teres (LT) to hip stability in the presence of an intact capsule with special attention to the change in range of motion and femoral head translation.

METHODS

Seven fresh-frozen cadaveric pelvises were used. Following visual inspection of the LT at different hip positions, internal rotation angles were measured at 10° of extension and at 0° of flexion, while external rotation was measured at 60°, 90°, and 110° of flexion with different hip abduction angles using electromagnetic motion tracking sensor. Femoral head translations were measured simultaneously. The tests were repeated after resection of the LT. The capsule was left intact for all test conditions. The results were compared between intact and LT resected conditions when torque of 2 and 4 Nm was applied.

RESULTS

Compared with the intact hip, the LT resected hip showed no significant difference when 2 Nm torque was applied in all scenarios. With 4 Nm torque application, significant increase in external rotation was found at 60° and at 90° of flexion (1.7° ± 0.8° and 2.1° ± 1.0°, respectively). Significant difference was also noted at 60°, 90°, and 110° of flexion when the hip was in the adducted position while at 90° in the abducted hip. However, LT resection did not show significant change in internal rotation. There was no significant difference in the translation distance of the femoral head in the intact hip compared with the LT resected hip (0.77-1.11 mm vs 0.79-1.29 mm).

CONCLUSIONS

Our results indicate that within the physiologic range of motion, LT can minimally limit external rotation when the hip is in the flexed position but does not contribute to translation stability.

CLINICAL RELEVANCE

In the hip with intact capsule, LT deficiency can result in a slight increase in range of motion, but its contribution to stability is questionable.

Medial approach open reduction with ligamentum teres partial excision and plication for the management of congenital hip dislocation

Because of the known tendency for early redislocation following open reduction, we developed surgical methods for shortening the ligamentum teres to improve immediate postoperative stability when performing medial approach open reduction (MAOR) for the management of developmental dysplasia of the hip. Between 2004 and 2014, 32 patients with dysplasia of the hip were managed by MAOR with partial excision and plication of ligamentum teres. The patients were followed up for an average of 6.9 years. At the final follow-up, clinical outcomes achieved were categorized as excellent and good in 39 (39/40; 97.5%) hips. At the latest follow-up, 97.5% (39 hips) were classified as good or excellent on the basis of the Severin classification (Severin grade 1 or 2). In conclusion, this series of MAOR, in which ligamentum teres partial excision and plication was utilized, we found stable reduction in all hips. On the basis of these positive results, we recommend this method for children treated with MAOR.

LEVEL OF EVIDENCE

Level IV: case series.

Simultaneous acetabular labrum and ligamentum teres reconstruction: a case report

This study aims to present the surgical technique for reconstructing both the acetabular labrum and the ligamentum teres and to describe the early outcomes of this procedure in a 15-year-old male with recurrent hip instability. A 15-year-old patient with recurrent left hip dislocation, hip joint instability and failed non-operative intervention presented following two left hip dislocations. A labral reconstruction was performed utilizing an iliotibial band allograft tissue with a concomitant ligamentum teres reconstruction using a tibialis anterior allograft. The patient was assessed pre- and postoperatively using modified Harris Hip Score, Lower Extremity Functional Scale and Visual Analogue Scale for pain and satisfaction. The patient reported improvement on all measures, including hip stability 14 months following surgery. The patient has not reported any episodes or subjective feelings of instability, has not required further surgical procedures in the hip and has returned to full sports participation. This case report demonstrates a technique for and early outcomes of simultaneous arthroscopic ligamentum teres and acetabular labrum reconstruction in a patient with recurrent hip instability. Short-term outcomes suggest improved hip stability, reduced pain, high patient satisfaction and return to pre-injury activities at 14 months postoperative in this single case report.

Editorial Commentary: Arthroscopic Hip Ligamentum Teres Reconstruction-Reality or Mythology?

The ligamentum teres (LT) is perceived to contribute to hip stability and proprioception. LT incompetence can lead to pain and instability, which may play a role in chondral damage. Hip arthroscopy plays a role in diagnosing and treating LT tears. Reconstruction of the LT is feasible, but careful attention needs to be paid to tunnel positioning, graft material, graft length, and fixation methods. An anatomic femoral tunnel should exit at the fovea capitis on the femoral side, whereas the location for safe placement of the acetabular attachment is thought to be in the posteroinferior part of the cotyloid fossa. On the basis of a recent study, optimization of the acetabular tunnel can potentially be achieved by drilling from the femoral tunnel aided by 15° of abduction and 15° of internal rotation. The femoral neck-shaft angle and femoral anteversion must be factored in while planning the entry point of the femoral tunnel, and this may vary based on the amount of femoral head distraction during hip arthroscopy.

The role of the ligamentum teres in the adult hip: redundant or relevant? A review

The ligamentum teres (LT) has traditionally been described as a redundant structure with no contribution to hip biomechanics or function. There has been renewed interest in the LT as a source of hip pathology due to the high prevalence of LT pathology observed at the time of hip arthroscopy. The LT acts a secondary stabilizer to supplement the work of the capsular ligaments and works in a sling-like manner to prevent subluxation of the hip at the extremes of motion. The presence of free nerve endings within the LT indicates a definite role in pain generation, with the LT undergoing various mechanical and histological adaptations to hip pathology.

A Technique for Arthroscopic-Assisted Ligamentum Teres Augmentation Using a Suture Tape Augmentation

Ligamentum teres (LT) tears are a pathologic condition being identified at increasing frequency because of growing use of hip arthroscopy. The exact role of the LT is not well understood, but it has been shown in recent biomechanical studies to contribute to hip stability. Patients with hip pain, instability, and/or mechanical symptoms with advanced imaging findings showing LT pathology may benefit from an LT augmentation. We present an arthroscopic-assisted LT augmentation technique, which can be performed as an isolated procedure or in conjunction with an arthroscopic labral repair and/or debridement, chondroplasty, and femoroplasty.

A novel and simple classification for ligamentum teres pathology based on joint hypermobility

Ligamentum teres (LT) pathology (including synovitis, partial and complete tears) is common at the time of hip arthroscopy with a reported prevalence of 51–90%. Currently, there are four published classifications of LT injuries and tears. The majority focuses on differentiating partial from full thickness tears, whereas a more recently published classification also incorporates the presumed underlying mechanism of pathology. A recent review of the current classification systems found that all are deficient for lack of inclusion of what constitutes a normal ligament, lack of inclusion of synovitis as a source of pathology and lack of inclusion of hypermobility as part of the treatment algorithm. Also, the two most commonly used classification systems have only fair inter-observer reliability. Recent work has found that underlying joint hypermobility plays an important role in LT pathology and that the addition of capsular plication/suture at the time of surgery for LT pathology improves outcomes and reduces re-tear rates. In order to address these problems which have been identified with the currently available classification systems, we propose a novel and simple classification for LT pathology based on underlying joint hypermobility [as assessed by the Beighton test score (BTS)]. LT pathology is used to divide all patients into four types: 0 normal (which includes minor fraying), 1 synovitis (which would also include minor fraying), 2 partial tear and 3 complete tear. Further, all types are subdivided into two groups: Group A patients have no clinical evidence of joint hypermobility (BTS < 3), whereas Group B patients do have clinical evidence of joint hypermobility (BTS ≥ 4). On the basis of this classification system and the available literature, we have also developed a treatment algorithm for LT pathology.

Do Ligamentum Teres Tears Portend Inferior Outcomes in Patients With Borderline Dysplasia Undergoing Hip Arthroscopic Surgery? A Match-Controlled Study With a Minimum 2-Year Follow-up

BACKGROUND

Arthroscopic surgery in borderline dysplastic hips remains controversial, but the role of the ligamentum teres (LT) has not been studied in this setting.

HYPOTHESIS

Borderline dysplastic patients with LT tears have worse short-term outcomes than those without LT tears.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected on patients who underwent arthroscopic surgery between February 2008 and April 2014. The inclusion criteria were borderline dysplasia (lateral center-edge angle [LCEA], 18°-25°) and labral tears; arthroscopic treatments including labral preservation and capsular plication; and preoperative patient-reported outcome scores including the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score-Sport-Specific Subscale, and visual analog scale for pain. Patients were excluded for preoperative Tönnis osteoarthritis grade >0, workers' compensation claims, previous ipsilateral hip surgery and conditions, or frank dysplasia (LCEA <18°). Patients with LT tears were pair-matched to patients without tears for sex, age at surgery ±10 years, body mass index (<30 kg/m² vs ≥30 kg/m²), labral treatment type, and microfracture.

RESULTS

Of 68 eligible patients, 63 (93%) had a minimum 2-year follow-up, and 30 (48%) had LT tears. Twenty patients in each group were pair-matched. The mean follow-up time was 54.3 months (range, 24.2-83.8 months) for the LT tear group and 38.6 months (range, 24.6-70.6 months) for the control group ( P = .002). Ninety percent were female. There were no significant differences regarding demographics or intra-operative procedures. The LT tear group trended toward lower postoperative mHHS ( P = .09) and NAHS ( P = .09) values. Mean satisfaction was 8.1 for the LT tear group and 7.9 for the control group. Preoperative and follow-up scores were not significantly different between the groups. The LT tear group had 5 revisions, with 1 revision in the control group. Three patients (15%) in the LT tear group underwent total hip arthroplasty (THA); no patients in the control group required THA.

CONCLUSION

In borderline dysplastic patients undergoing hip arthroscopic surgery with labral treatment and capsular plication, LT tears may indicate advanced instability and portend slightly inferior outcomes when compared with a match-controlled group. Borderline dysplastic patients with LT tears may have increased propensities toward revision arthroscopic surgery and conversion to THA. LT tears in these patients may warrant consideration for additional procedures including periacetabular osteotomy and LT reconstruction.

The reliability of commonly used arthroscopic classifications of ligamentum teres pathology

The importance of the ligamentum teres (LT) in the hip is increasingly being recognized. However, the incidence of LT tears in the literature is extremely variable. Although classification systems exist their reliability in classifying LT pathology arthroscopically has not been well defined. To determine the inter- and intra-observer reliability of two existing classifications systems for the diagnosis of LT pathology at hip arthroscopy. Second, to identify key pathological findings currently not included. Four experienced hip-arthroscopists reviewed 40 standardized arthroscopic videos. Arthroscopic findings of the LT were classified using the Gray and Villar (G&V) and descriptive classification (DC). Reviewers were asked to record other relevant pathology encountered. Inter- and intra-observer reliability was defined using Fleiss-Kappa and Cohen-Kappa statistics. Both classifications demonstrated fair inter-observer reliability. The intra-observer reliability for G&V was moderate-to-substantial and for DC was slight-to-moderate. An absolute agreement rate of 10% (G&V) and 37.5% (DC) was found. Differentiation between normal, and partial or low-grade tears was a common source of disagreement. The prevalence of LT pathology was 90%. Synovitis was the most common diagnostic finding that was not included in either classification system used in this study. Arthroscopic classification of LT pathology using the G&V and the DC demonstrated only fair inter-observer reliability. The major discrepancy in interpretation was between normal, and partial or low-grade tears. The presence of synovitis was not in either classification but was considered an important arthroscopic finding. Thorough arthroscopic scrutiny reveals the prevalence of LT pathology is higher than previously reported.

Ligamentum teres tendinopathy and tears

BACKGROUND

The ligamentum teres (LT) consists of two bands that originate on the ischial and pubic sides of the acetabular notch and insert on the fovea capitis of the femoral head. Recent studies have established the LT as an important hip stabilizer in a squatting position, particularly in patients with osseous instability.

PURPOSE

This review aims to concisely present the literature on LT tendinopathy and tears in order to guide health care professionals in the appropriate diagnosis and treatment of these disorders.

METHODS

We reviewed the literature on the diagnosis and surgical management of ligamentum teres tendinopathy and tears.

CONCLUSIONS

The ligamentum teres is an important stabilizer to the hip joint, particularly with hip flexion and external rotation. Older age and acetabular bony pathomorphology are two of the known risk factors for LT tears. Symptoms of LT tendinopathy are largely non-specific, mimicking a wide range of other hip disorders including impingement and instability. Debridement of LT tears or reactive tissue has been reported with good outcomes, with more recent studies describing reconstruction of a completely torn, nonfunctional, or absent LT using various graft sources including synthetic grafts, autografts, and allografts.

LEVEL OF EVIDENCE

II.

The role of arthroscopy in the dysplastic hip-a systematic review of the intra-articular findings, and the outcomes utilizing hip arthroscopic surgery

Acetabular dysplasia is one of the most common sources of hip arthritis. With the recent innovation in hip arthroscopy, the question has been raised whether arthroscopy can be used to treat dysplastic hip conditions. The purposes of this systematic review are (i) describe the prevalence of intra-articular pathologies and (ii) report the outcomes of dysplastic hip treatment with hip arthroscopy as a sole treatment. Medical databases were searched for articles including arthroscopic findings and treatment of dysplastic hip with predetermined criteria. PubMed, Ovid database and CINAHL (Cumulative Index to Nursing and Allied Health Literature) were searched up until 7 January 2015. Two reviewers independently assess the eligibility of retrieved studies using titles, abstracts and full-text articles. Thirteen studies were eligible to be included for the systematic review. Overall, labral tear was the most common pathology with a prevalence rate of 77.3%. All of the four studies describing arthroscopic treatment for only borderline dysplasia reported favorable outcome. With regard to more severely dysplastic hips, two out of three studies reported acceptable outcomes while one study reported negative results. This review indicates that intra-articular pathology is commonly observed in symptomatic dysplastic hips with a labral tear being the most common pathology. Arthroscopic treatment of borderline dysplasia could provide benefits whereas treatment of more dysplastic hips is controversial. Nevertheless, there is a lack of evidence for using arthroscopy alone in hips with a center edge angle <20°. Level IV, systematic review of Level IV studies.

Arthroscopic reconstruction of the Ligamentum Teres: a case series in four patients with connective tissue disorders and generalized ligamentous laxity

This study presents the results of four Ligamentum Teres (LT) reconstruction procedures for hip instability with an average of 21.4 months follow-up (range 16.4–27.8). The indication for reconstruction was patients who complained of hip instability (hip giving way on gait or activities of daily living) on a background of a connective tissue disorder and generalized ligamentous laxity. The following data were recorded: age, sex, body mass index, hip range of motion, impingement signs, acetabular coverage (lateral center edge angle and acetabular inclination), acetabular retroversion (ischial spine sign and a crossover sign), femoral alpha angles and femoral neck shaft angles. Four patient recorded outcomes (PROs) were collected at 3 months, 12 months and 24 months. Three patients were female. Three out of four procedures had an improvement in PROs. One patient with bilateral procedures had an improvement in PROs on one side at 1 year but a failure of the graft on the contralateral side. There were no complications reported with the technique. LT reconstruction and concomitant capsular plication in this case series is associated with an improvement in outcomes in three out of four of the patients with hip instability associated with a full thickness tear of the LT and who presented with hip instability on a background of generalized ligamentous laxity and a connective tissue disorder. However, the physical examination, radiographic and intra-operative findings which may help predict who would benefit from LT reconstruction require further investigation.

Ligamentum teres injuries - an observational study of a proposed new arthroscopic classification

Ligamentum teres (LT) Injuries or tears have been said to be a common cause of groin discomfort and pain, and they have been identified in 8–51% of patients undergoing hip arthroscopy. Currently, in the literature there exist three arthroscopic classifications for LT injuries and tears: the first classification was established by Gray and Villar, Botser and Domb proposed the second one which they called a descriptive classification according to the degree of partial thickness LT tears and more recently the last classification by Cerezal et al. (RadioGraphics 2010; 30:1637–51), where they take into account the one by Gray and Villar but adding an avulsion fracture and absence of the LT. We propose a new classification, which also takes into account, observed LT pathologies, as well as the possible pathological mechanism of LT tears, and offer a guide to treatment. This classification is based on direct arthroscopic observation and dynamic rotational maneuvers of the hip under distraction. This classification incorporates those pathologies, which have been observed as a result of this more focused examination of the LT.