Simultaneous acetabular labrum and ligamentum teres reconstruction: a case report

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.

Ligamentum Teres Lesions Are Associated With Poorer Patient Outcomes in a Large Primary Hip Arthroscopy Cohort of 1,935 Patients

Purpose

To retrospectively evaluate the prevalence and characteristics of ligamentum teres (LT) lesions identified in a single-surgeon hip arthroscopy cohort and to compare surgical outcomes of those with, and without, identified LT lesions.

Methods

Patients who underwent primary hip arthroscopy between 2005 and 2018 in one surgeon’s clinic were identified. Those with a history involving extra-articular scoping or any previous surgery on the ipsilateral hip were excluded. Patient-reported outcome measures completed before and after surgery included the Hip Disability and Osteoarthritis Outcome Score, Nonarthritic Hip Score, and 12-item International Hip Outcome Tool. Conversion to hip joint replacement was ascertained through a national register.

Results

A total of 1,935 primary hip arthroscopies (from 1,607 different patients) were included in this study. In total, 323 LT lesions were identified. Those with LT lesions were older than those without (40.3 ± 11.3 years compared with 33.9 ± 12.1 years; P < .001), and more frequently female (58.2% vs 41.8%; P = .001). Hips with lesions had a smaller lateral center-edge angle than other hips (33.0 ± 6.8° vs 34.1 ± 6.0°; P = .004). All patient-reported outcome measures improved significantly (P < .001) from pre- to post-surgery for patients with and without LT lesions. However, patients with LT lesions reported less improvement in the 12-item International Hip Outcome Tool (difference –5.60; P = .004) and in Hip Disability and Osteoarthritis Outcome Score symptoms (–4.41; P = .004), sports (–7.81; P < .001), and quality of life subscales (–8.85; P < .001) than those without lesions. Hips with LT lesions also had a 6.2% 2-year rate of subsequent hip replacement (20/323 hips) compared with those without lesions (0.9%; 14/1612 hips; P < .001).

Conclusions

In this single-surgeon hip arthroscopy cohort, identification of LT lesions was associated with poorer patient-reported outcomes and increased likelihood of conversion to arthroplasty within 2 years. These findings suggest a poorer prognosis for patients with LT injury compared with those without.

Level of Evidence

Level III, retrospective cohort study.

Ligamentum teres reconstruction with labrum and capsule repair after posterior acetabular wall fracture: a case report

The aim of this case study is to present arthroscopic treatment of recurrent hip instability after acute post-traumatic posterior hip dislocation with a fracture of the posterior acetabular wall. A male patient aged 35 suffered a dislocation of the right hip joint with a fracture of the posterior acetabular wall due to an accident. The fracture was stabilized during emergency surgery with a locking compression plate, and the patient was released home in a hip brace. Multiple dislocations of the hip joint followed with the implant being confirmed as stable. Decision was made to qualify the patient for a right hip arthroscopy. During the surgery, ligamentum teres was reconstructed using gracilis and semitendinous muscle grafts, followed by the labrum and joint capsule repair, where the surgery that stabilized the acetabular wall fracture had damaged them. There were no complications following the procedure. Short-term follow-up of 3 months demonstrates the patient has a stable hip, reduced pain and has returned to pre-injury activities.

Indications and Outcomes After Ligamentum Teres Reconstruction: A Systematic Review

Purpose

To systematically review the literature to better understand the current indications for ligamentum teres reconstruction (LTR), current graft and acetabular fixation options used, patient-reported outcomes after LTR, and incidence of complications and reoperations after LTR.

Methods

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. All literature related to LTR published prior to July 2020 was identified. The inclusion criteria consisted of investigations reporting on human patients with pathology of the ligamentum teres who underwent LTR, including mentions of the indications, graft type, acetabular fixation method, postoperative patient-reported outcome scores, and incidence of complications and reoperations.

Results

Seven studies comprising 26 patients (28 hips) were included. The most commonly reported indication for LTR was persistent pain and instability after failed prior hip arthroscopy (68%, 19 of 28 hips). The mean postoperative modified Harris Hip Score, Non-arthritic Hip Score, and visual analog scale score all showed improvement when compared with preoperative values. A total of 2 complications occurred. Complication rates ranged from 0% to 100% in included case reports and 0% to 11% in included case series. A total of 9 reoperations were performed. Reoperation rates ranged from 0% to 100% for case reports and 18% to 100% for case series. Reoperation rates ranged from 33% to 100% in studies with patients receiving acetabular fixation using anchors versus 0% to 22% in studies performing LTR with buttons. Reoperation rates in athletic patients and patients with Ehlers-Danlos syndrome ranged from 0% to 100% and 0% to 50%, respectively.

Conclusions

The main indication for LTR was persistent hip or groin pain and instability after a prior hip arthroscopy. The short-term postoperative modified Harris Hip Score, Non-arthritic Hip Score, and visual analog scale score after LTR showed favorable outcomes. However, reoperations after LTR were not uncommon.

Level of Evidence

Level V, systematic review of Level IV and V studies.

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.