The popliteus tendon provides a safe and reliable location for all-inside meniscal repair device placement

Evaluation of healing after arthroscopic repair of lateral meniscal tears around the popliteal hiatus

BACKGROUND

The popliteal hiatus stabilizes the lateral meniscus (LM). Variable failure rates for LM repairs have been reported in knees with lateral meniscal tears (LMTs), which may be attributable to low vascularity around the popliteal hiatus. An effective repair method is essential to enhance the biological healing and stability of LMTs around the popliteal hiatus.

HYPOTHESIS

Arthroscopic repair of LMTs, including the popliteus tendon around the popliteal hiatus, is expected to produce a low reoperation rate and effective treatment, both clinically and radiographically.

MATERIAL AND METHODS

From June 2011 to August 2020, 93 patients (mean age 27.9 ± 13.5 years) who underwent arthroscopic repair of LMTs including the popliteus tendon around the popliteal hiatus were enrolled. Patients with LMTs were divided into three groups: isolated LMTs, discoid LMTs, and LMTs with ACL injury. Patients had a minimum clinical follow-up of 2 years (mean 37.9 ± 19.3 months) and Tegner activity, Lysholm knee, and Hospital for Special Surgery (HSS) scores were evaluated for all patients. The widths of the popliteal hiatus and LM extrusion were measured on the sagittal and coronal planes using preoperative and postoperative magnetic resonance imaging (MRI).

RESULTS

The Tegner activity (2.6 ± 1.2-4.5 ± 1.3), Lysholm (67.9 ± 14.2-88.1 ± 6.4), and HSS scores (79.8 ± 11.5-93.7 ± 5.1) were significantly improved in all knees (p < 0.001). The width of the popliteal hiatus measured on MRI was significantly decreased, when comparing the preoperative and postoperative MRI for all knees (sagittal plane, 2.9 ± 1.4-1.5 ± 0.5 mm; coronal plane, 3.8 ± 2.5 to 1.9 ± 1.0 mm) (p < 0.05). The LM extrusion measured on the sagittal plane of postoperative MRI was also significantly reduced after arthroscopic repair (24.8 ± 3.1-23.7 ± 2.8 mm) (p = 0.001). Five reoperations (5/93, 5.3%) were performed, suggesting a clinical failure.

CONCLUSION

Arthroscopic repair of isolated, discoid and post-traumatic LMTs including the popliteus tendon around the popliteal hiatus, is an effective surgical treatment for LM stabilization.

LEVEL OF EVIDENCE

Level IV, retrospective series.

Tears of Popliteomeniscal Fascicles and Meniscofibular Ligament in Popliteal Hiatus Area: An Arthroscopic Repair Technique With Suture

In the popliteal hiatus area, instead of directly connecting to the capsule, the lateral meniscus attaches to the popliteal and fibular head through the popliteomeniscal fascicles and meniscofibular ligament. These connection tissues are vital to the stability of the lateral meniscus. However, reporting on injuries to these connection tissues is limited, and consensus on the treatment of such injuries is lacking. This article introduces an arthroscopic all-inside repair technique for meniscal tears involving popliteomeniscal fascicle and meniscofibular ligament injuries.

Influence and Clinical Significance of Knee Flexion Angle on the Anatomic Course of the Common Peroneal Nerve in the Posterolateral Corner of the Knee Joint

Background

Detailed knowledge of the anatomic course of the common peroneal nerve (CPN) is crucial for the surgical treatment of the posterolateral corner (PLC) of the knee.

Purpose

To investigate the relationship of the CPN to the PLC of the knee at different flexion angles.

Study Design

Descriptive laboratory study.

Methods

Ten healthy volunteers were recruited to undergo magnetic resonance imaging (MRI) of the knee joint at knee flexion angles of 0°, 30°, 60°, 90°, and 120°. MRI scans at 3 levels (joint line, tibial cut, and fibular tip) were evaluated to determine (1) the distance from the CPN to the PLC and (2) the distances between the CPN and the anterior-posterior and medial-lateral tibial axes. A 3-dimensional model of the knee joint created from MRI scans of a single participant was used to simulate the creation of a fibular tunnel for PLC reconstruction and investigate the relationship between the CPN, fibular tunnel, and guide pin.

Results

The CPN moved posteromedially with increased knee flexion angles. As the flexion angle increased, the distances from the CPN to the anterior-posterior axis and the PLC increased significantly, while the distance to the medial-lateral axis decreased significantly at all 3 measurement levels. The distances between the CPN and anterior-posterior and medial-lateral axes were significantly different among the different knee flexion angles at the different measurement levels. There were no significant differences in the mean distance from the CPN to the posterolateral border of the tibial plateau between 0° and 30° of flexion at the fibular tip level (P = .953). There were statistically significant differences in the distance from the CPN to the PLC of the tibial plateau at the different measurement levels. The 3-dimensional model demonstrated that the position of the CPN relative to the guide pin and the bone tunnel undergoes changes during knee flexion.

Conclusion

Changes in the knee flexion angle produced corresponding changes in the course of the CPN on the posterolateral aspect of the knee joint. The CPN moved posteromedially with increased knee flexion angles.

Clinical Relevance

Increasing the knee flexion angle during PLC reconstruction can effectively avoid direct injury of the CPN.

Meniscal Repair Outcome in 3829 Patients With a Minimum Follow-up From 2 Years Up to 5 Years: A Meta-analysis on the Overall Failure Rate and Factors Influencing Failure

BACKGROUND

The importance of meniscal repair is widely accepted because of the association of loss of meniscal tissue with the development of early-onset knee arthritis. Many factors influencing the results of meniscal repair have been reported, but results remain controversial.

PURPOSE

This meta-analysis determines the pooled meniscal repair failure rate of studies with a minimum follow-up of 2 years up to 5 years, with a mean follow-up of 43 months. Moreover, selected failure-influencing factors are analyzed.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed and Scopus were searched for studies published between January 2000 and November 2021 reporting on meniscal repair outcome with a minimum follow-up of 24 months. The overall pooled failure rate and pooled failure rates for possible predictors were calculated. Random-effect models were used to pool failure rates, and effect estimates in the form of odds ratios with 95% CIs were established.

RESULTS

The initial literature search identified 6519 studies. A total of 51 studies met the inclusion criteria. In total, 3931 menisci were included with an overall failure rate of 14.8%. Subgroup analysis revealed a significantly lower failure rate for meniscal repair with concomitant anterior cruciate ligament (ACL) reconstruction compared with knees without any reported injury to the ACL (8.5% vs 14%; P = .043). The pooled failure rate for lateral meniscal repair was significantly lower than that for medial meniscal repair (6.1% vs 10.8%; P = .031). Pooled failure rates of all-inside and inside-out repair were not significantly different (11.9% vs 10.6%; P > .05).

CONCLUSION

This meta-analysis on close to 4000 patients demonstrates an overall meniscal repair failure rate of 14.8% at a minimum follow-up from 2 years up to 5 years. Meniscal repair remains a procedure with a high failure rate, especially within the first 2 postoperative years. This review and meta-analysis also identified clinically relevant factors associated with favorable outcomes such as concomitant ACL reconstruction or repair of the lateral meniscus. All-inside meniscal repair with the latest-generation devices yields failure rates of <10%. The failure mechanism and the time of failure is poorly documented; further studies are needed for a better understanding of the retear mechanism.

Mid-Term Clinical and Radiological Outcomes of Lateral Meniscal Allograft Transplantation with Suture-Only Fixation Plus Capsulodesis

Meniscal allograft transplantation (MAT) is an effective reconstructive procedure for treating a symptomatic postmeniscectomy syndrome. It consists of replacing the lost meniscal tissue aiming to improve the clinical outcomes and prevent progressive deterioration of the joint. The aim of this study was to evaluate meniscal graft survivorship and report on the radiographic (in terms of graft extrusion and joint space width and alignment) and the functional results through a midterm follow-up of lateral MAT performed with a soft tissue fixation technique after capsulodesis. In total, 23 patients who underwent lateral MAT as a single procedure were included. The Knee injury and Osteoarthritis Outcome Score, Lysholm, Tegner, and visual analog scale scales were used for patient assessment. Magnetic resonance imaging and a complete radiographic protocol were conducted to determine the degree of meniscal extrusion and the changes in the degree of osteoarthritis and coronal alignment. Assessments were performed after 2 and 7 years of follow-up. A significant improvement in all the scores, relative to preoperative values, was found after 7 years of follow-up. This improvement remained consistent throughout the first and second follow-up periods. A mean absolute extrusion of 2.2 mm ± 1.6 and an extrusion percentage of 28.0% ± 11.43 were found, with no significant differences throughout the follow-up periods. There was no statistically significant difference in terms of the frontal mechanical axis and joint space narrowing between the preoperative value and at the first and second follow-up periods. A survival rate of 85.7% was found after 7 years of follow-up. Capsulodesis results in a low degree of meniscal extrusion in isolated lateral MAT fixed with a suture-only technique, which is maintained after 7 years of follow-up, with a high graft survival index (>85%) and satisfactory results on the functional scales.

Is the popliteal tendon sufficient for all-inside suture in lateral meniscus repair? A 22-case cadaver study

INTRODUCTION

Arthroscopic lateral meniscus repair is performed in the "figure-of-4 position" (supine, with the affected knee flexed and the lower leg crossed over the extended contralateral leg), and anchorage is often on the popliteal tendon. Extending the limb at the end of the procedure alters the relations between the popliteal tendon and the repaired meniscus. The present study aimed to assess lateral meniscal suture fixation on the popliteal tendon after a cycle of flexion-extension.

HYPOTHESIS

Extending the knee can induce suture release.

TYPE OF STUDY

Cadaver study.

MATERIALS AND METHODS

Twenty-two fresh adult human cadaver knee specimens were used. Under arthroscopy with all-inside implants, a vertical suture onto the popliteal tendon was performed through the lateral meniscus. Suture status was assessed under arthroscopy after a cycle of flexion-extension, and deemed defective if the suture was sufficiently loose for the arthroscope to be able to be passed through the popliteal hiatus, if the stitch had passed through the meniscus, or if the suture was broken.

RESULTS

Thirteen sutures (59.1%) remained well fixed, and 9 (40.1%) were defective: 4 (18.2%) were loose, in 4 (18.2%) the stitch had passed through the meniscus, and in 1 (4.5%) the suture had broken.

CONCLUSION

In a population of elderly cadaver knee specimens, arthroscopic suture of the lateral meniscus to the popliteal tendon was defective after flexion-extension in 40% of cases. Stress seems to be exerted on the suture when extension is resumed. Thus, a single stitch seems insufficient for stable lateral meniscus repair.

CLINICAL IMPLICATIONS

Suture of the lateral meniscus to the popliteal tendon undergoes stress when extension is resumed, potentially causing failure of lateral meniscus repair.

LEVEL OF EVIDENCE

IV.

LARAI portal provides a safe method for lateral meniscus repair: three-dimensional computed tomography and cadaveric assessment

BACKGROUND

Lateral, All-Round and All-Inside (LARAI) portal is a viewing or working portal for observing and repairing the lesions of the lateral meniscus. However, there are safety concerns about popliteal artery (PA) injuries during the procedure. This study aimed to assess the safe distance between the trajectory of the LARAI portal and PA.

MATERIALS AND METHODS

Both three-dimensional computed tomography (3D-CT) and cadavers were used to simulate the LARAI portal trajectory. In the 3D-CT study, between January 2020 and September 2020, 45 participants who underwent computed tomography angiography were included in the study. The shortest distance from the PA to the simulated trajectory needle (PS) was measured using 3D-CT. Mean -3SD -2 was calculated to assess the safety of the LARAI portal trajectory. If this value was more than zero, the trajectory was considered "safe." In the cadaveric study, lower limbs from seven fresh-frozen cadavers were used to establish the "safe" trajectories of the LARAI portal, and the PS was measured.

RESULTS

In the 3D-CT study, the longest PS (P < 0.001) was found 20 mm lateral to the edge of the patellar tendon trajectory at 0 mm from the posterior cruciate ligament (PCL). Safe trajectories were also found 10 mm, 15 mm, and 20 mm lateral to the edge of the patellar tendon at 0 mm from the PCL, as well as the 20 mm lateral to the edge of the patellar tendon at 3 mm from the PCL. The cadaveric study showed that the average PS of all safe trajectories closely adjoined to PCL was greater than 14 mm.

CONCLUSIONS

The LARAI portal trajectory in the "figure of four" is safe, and the optimal insertion point is 10-20 mm lateral to the edge of the patellar tendon and closely adjoined to the posterolateral margin of the PCL at knee joint line level.

LEVEL OF EVIDENCE

Level IV.

Clinical presentation and arthroscopic treatment of hypermobile Type III Wrisberg variant of lateral discoid meniscus: Report of nine cases

BACKGROUND

The aim of the present study was to document a series of patients with meniscal hypermobility due to a Type III Wrisberg variant lateral discoid meniscus, describing their clinical presentation, analyzing their magnetic resonance imaging (MRI) and arthroscopic characteristics, and reporting the outcomes of an all-inside stabilization.

METHOD

Nine cases of Wrisberg variant Type III discoid lateral menisci were identified based on patient's history and clinical examination. Knee MRIs were reviewed to exclude the presence of Type I-II discoid meniscus (complete or incomplete) or bucket handle tears and general arthroscopic criteria. For the Wrisberg variant discoid lateral meniscus were applied for the final diagnosis.

RESULTS

All nine cases presented similar peculiar clinical, radiological, and arthroscopic features, which led to the diagnosis of hypermobile Wrisberg variant of lateral discoid meniscus. This rareclinical entity is responsible for suggestive symptoms such as pain, popping and knee locking; moreover, subtle but peculiar MRI and arthroscopic characteristics can be observed.

CONCLUSION

Considering the possibility of repeated dislocation and relocation, diagnosis can be challenging, and a high degree of suspicion should be used, especially in young patients, bilateral symptoms, and absence of trauma.

No risk of iatrogenic peroneal nerve injury in all-inside lateral meniscal repair with either 14- or 18-mm needles through the popliteus tendon in the standard arthroscopic knee conditions

PURPOSE

The objectives of this prospective study were to evaluate the risk of peroneal nerve (PN) injury in simulated all-inside lateral meniscal repair with sutures placed through the popliteus tendon (PT) and to determine the optimal needle length.

METHODS

Twenty-nine axial magnetic resonance images (MRI) of postoperative knees with infused intra-articular fluid and in a figure-of-four position were used. The cross-sectional length of the PT was divided into four equal parts with measurements performed at the 25%, 50% and 75% points according to their anteroposterior arrangement. Simulated repairs were performed with 14-mm and 18-mm straight needles via the anteromedial (AM) and anterolateral (AL) portals. Distances from the needle tip following full insertion through the PT to the PN and from the anterior PT border to the posterior knee capsule were measured to determine PN injury risk and ideal needle insertion depths at the different landmarks.

RESULTS

Simulated repairs on the 29 knee MRI images resulted in no incidences of PN injury. The average distances from the needle tip to the PN of the 14-mm needle were significantly greater than the 18-mm needle in all the simulated repairs (P < 0.02), except at the 25% point in the AM approach. When using the 14-mm needle, capsule underpenetration was found in three knees (10.3%) at the 25% point during the AM approach, in one knee (3.4%) at the 50% and 75% points in the AM approach, and in all repairs from the AL portal. The average distances from the anterior PT border to the capsule at the 25%, 50%, and 75% division points on the PT in the AM approach were 7.7 ± 2.7 mm, 7.9 ± 2.5 mm and 7.6 ± 2.8 mm, respectively, whilst in the AL approach were 8.4 ± 2.9 mm, 8.1 ± 2.8 mm and 7.6 ± 2.7 mm.

CONCLUSION

Simulated all-inside lateral meniscal repair with suture placement through the PT with 14-mm and 18-mm needles was safe. The measurements in this study can be used to determine potential PN injury risk in relation to the PT and the appropriate needle length for safe lateral meniscal repairs.

True all inside meniscus repair using the popliteus tendon

The popliteus tendon is a useful anchor point to repair the posterior horn of the lateral meniscus. We describe a new, economical technique that does not violate the neurovascular structures, using an antegrade suture passer and a 2-0 fiberwire to repair the posterior segment including posterior horn of the lateral meniscus taking bites through the capsule and meniscus or the popliteus tendon and meniscus with no anchors in the capsule or popliteus. 9 patients were operated upon using this technique and the mean IKDC score improved from 24.2 to 84, p < 0.01, mean pre op Tegner improved from 1.88 to 6.63 p < 0.01, median hop test from 0 to 4, p = 0 at a mean 15.2 months post surgery. 8 patients had a negative Lachman and 1 grade 2 Lachman at 12 months follow up but was asymptomatic. The Barret's criteria was negative for all 9 patients at latest follow up.

Tears of the Popliteomeniscal Fascicles of the Lateral Meniscus: An Arthroscopic Classification

OBJECTIVE

To bring forward an arthroscopic classification of the popliteomeniscal fascicles of the lateral meniscus (PFLM) tears.

DESIGN

Six fresh frozen knee joint samples of adult males were chosen, and the lateral meniscus at the popliteal hiatus region were measured to analyze their anatomic relationship. Patients who had received magnetic resonance imaging scan at knee joint before the surgery and diagnosed as PFLM tears by arthroscopy from April 2014 to October 2017 were selected. Data regarding the integrity of PFLM were prospectively recorded in a data registry. Tear morphology and treatment received were subsequently extracted by 2 independent reviewers from operative notes and arthroscopic surgical photos.

RESULTS

The average length and thickness of the popliteal hiatus of the lateral meniscus were 2.09 ± 0.21 cm and 0.43 ± 0.08 cm, respectively. The average length of anterosuperior popliteomeniscal fascicle (APF) was 0.87 ± 0.18 cm, and the posterosuperior popliteomeniscal fascicle (PPF) was 0.72 ± 0.15 cm. A total of 36 PFLM tears in 36 patients were divided as type I (APF tear; n = 5, 13.9%), type II (PPF tear; n = 20, 55.6%), and type III (both APF and PPF tears; n = 11, 30.6%). All patients were treated with arthroscopic all-inside repair using a suture hook for the PFLM tears and follow-up for 21.1 months. All patients have done well with significantly improved Lysholm and International Knee Documentation Committee scores at the last follow-up relative to preoperative scores (P < 0.01).

CONCLUSION

This study suggests to possibly classify the PFLM tears for clinical practice.

[Arthroscopic classification and management for the popliteal hiatus of the lateral meniscus tears]

OBJECTIVE

To bring forward an arthroscopic classification of the popliteal hiatus of the lateral meniscus (PHLM) tears and to assess the effects of arthroscopic all-inside repair with suture hook in management of such injuries.

METHODS

This study involved 146 patients who underwent arthroscopic operation because of PHLM tears from April 2014 to October 2017, eliminating the patients who had discoid lateral meniscus. There were 81 males and 65 females, with 54 left knees and 92 right knees. The average ages were (34.7±3.7) years. Among the selected participants, there were 107 patients with anterior cruciate ligament (ACL) injuries, 39 patients with medial collateral ligament (MCL) injuries, and 48 patients with medial meniscus tears. The average preoperative Lysholm and International Knee Documentation Committee (IKDC) scores were 57.7±9.2 and 54.1±8.9, respectively. The arthroscopic classification was based on the extent and degree of PHLM tears and using the arthroscopic all-inside repair with suture hook for such injuries. For the patients associated with ACL injuries, the ipsilateral autograft hamstring tendons use as the reconstruction graft for single bundle ACL reconstructions. The suture anchors were used for treatment of MCL Ⅲ injuries, and the arthroscopic all-inside repair for medial meniscus tears.

RESULTS

A total of 146 PHLM tears in 146 patients were divided into type Ⅰ (tears not involved in popliteus tendon incisura; n=86, 58.9%), type Ⅱ (tears involved in popliteomeniscal fascicles; n=36, 24.7%), and type Ⅲ (tears involved in popliteus tendon incisura; n=24, 16.4%). For type Ⅰ, there were three subtypes, including type Ⅰa: longitudinal tear (n=53, 61.6%), type Ⅰb: horizontal tear (n=27, 31.4%), and type Ⅰc: radial tear (n=6, 7.0%). For type Ⅱ, there were also three subtypes, including type Ⅱa: anterosuperior popliteomeniscal fascicle tear (n=5, 13.9%), type Ⅱb: posterosuperior popliteomeniscal fascicle tear (n=20, 55.6%), and type Ⅱc: both tears (n=11, 30.6%). For type Ⅲ, there were two subtypes, including type Ⅲa: horizontal tear (n=9, 37.5%), type Ⅲb: radial tear (n=15, 62.5%). In the follow-up for an average of 15.3±2.6 months, all the patients had done well with significantly improved Lysholm (84.6±14.3) and IKDC (83.2±12.8) scores at the end of the last follow-up relative to preoperative scores (P > 0.01).

CONCLUSION

We propose that it is possible to classify lateral meniscus tears at the popliteal hiatus region for three types, which can summarize the injury characteristics of this area. The arthroscopic all-inside repair with suture hook for the PHLM tears can avoid stitching to popliteal tendon or narrowing popliteal hiatus and have satisfactory clinical results.

All-Inside Double-Sided Suture Repair for Longitudinal Meniscal Tears

The current consensus in the literature is that the meniscus must be saved. Even though inside-out sutures are still considered as the gold standard, the need to alternate between intra- and extra-articular structures for every stitch makes it laborious. New generations of all-inside systems are now routinely used in operating rooms and enable easier, quicker, and safer techniques. However traditional all-inside repair with limited upper fixation does not provide uniform compression from top to down, essential precondition for satisfactory meniscal healing. This Technical Note describes a simple and accessible alternative technique that provides stable fixation and overall compression of vertical meniscal tears from top to down with standard all-inside instrumentation.

Return-to-Sport Rate and Activity Level Are High Following Arthroscopic All-Inside Meniscal Repair With and Without Concomitant Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the literature of return-to-sport outcomes following all-inside meniscus repair and evaluate whether concomitant anterior cruciate ligament reconstruction (ACLR) influenced these outcomes.

METHODS

A systematic review of the MEDLINE, PubMed, Embase, and Cochrane Registry of Systematic Reviews databases was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two reviewers examined all literature pertaining to sport outcomes following all-inside meniscal repair. Studies were included if they had a 12-month minimum follow-up and reported return to sport rate, Tegner, or Knee injury and Osteoarthritis Outcome Score (KOOS) Sport outcomes. Studies with meniscal repair techniques other than the all-inside technique were excluded. Studies were not excluded if they contained patients receiving concomitant ACLR. Study quality was evaluated with the Methodological Index for Nonrandomized Studies.

RESULTS

Nineteen studies comprising 872 patients were included in this investigation. The weighted average patient age was 28.7 (range 14.1-42.1) years, and the weighted average follow-up was 56.0 (range 18.0-155.0) months. The mean Methodological Index for Nonrandomized Studies score was 14.4 ± 3.7. Ten investigations reported both preoperative (range 2.3-3.5) and postoperative (range 4.0-7.3) Tegner outcomes, with scores at final follow-up greater in each of the 10 reporting investigations. KOOS Sport outcomes were examined in 5 investigations, with scores at follow-up ranging from 63.6 to 91. Three studies reported a return to sport rate ranging from 89.6 to 90% at follow-up. Four investigations compared sport-related outcomes between isolated meniscal repair and meniscal repair with concomitant ACLR. Two such studies reported no difference between the 2 cohorts, 1 favored the isolated cohort, and 1 favored the combined cohort.

CONCLUSIONS

This systematic review found a 90% return-to-sport rate and high postoperative activity level following all-inside meniscal repair, as assessed by KOOS Sport and Tegner activity scales. Further, concurrent ACLR did not significantly affect these outcomes.

LEVEL OF EVIDENCE

IV, systematic review of level I-IV studies.

Quantitative and Qualitative Assessment of Posterolateral Meniscal Anatomy: Defining the Popliteal Hiatus, Popliteomeniscal Fascicles, and the Lateral Meniscotibial Ligament

BACKGROUND

Surgical treatment of lateral meniscal tears can be challenging due to the greater mobility of the lateral meniscus, thin capsule, and management of the popliteal hiatus. There has been a lack of quantitative assessments of the structural attachments to the posterior horn of the lateral meniscus (PHLM) to guide repairs.

PURPOSE

To qualitatively and quantitatively describe the anatomy of the PHLM, popliteomeniscal fascicles, and the posterolateral capsule.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Fourteen male, nonpaired, fresh-frozen cadaveric knees were used. The attachments of the posterolateral capsule, popliteomeniscal fascicles, and meniscofemoral ligaments to the lateral meniscus and the attachment of the meniscotibial ligament to the tibia were identified. A 3-dimensional coordinate measuring system was used to measure the relationships of these attachments to surgically relevant landmarks and their structural relationship with the lateral meniscus.

RESULTS

The posterolateral capsule attachment had a confluent attachment at the superior margin of the PHLM, quantitatively attaching to the proximal 11% of the total height of the PHLM. On average, the length of the posterolateral capsule attachment to the superior surface of the PHLM was 16.7 ± 2.7 mm. The average length of the meniscotibial attachment to the posteroinferior aspect of the meniscus was 12.8 ± 3.9 mm. There was a lack of ligamentous attachments to the lateral meniscus between the lateral aspect of the meniscotibial ligament and the anterior aspect of the anterosuperior popliteomeniscal fascicle, where only popliteomeniscal fascicle and capsular attachments to the posterior meniscus were present.

CONCLUSION

This anatomic study provides quantitative guidelines for the complex attachments to the PHLM. Knowledge of the quantitative descriptions of these attachments may aid in an improved intraoperative diagnosis of PHLM tears that extend to the popliteal hiatus, and further studies related to the surgical repair of the intricate attachments to the PHLM are recommended.

CLINICAL RELEVANCE

The findings of this study provide the anatomic foundation for an improved understanding of the role of the meniscocapsular, meniscotibial, and popliteomeniscal fascicle attachments of the posterolateral meniscus. Understanding the differences between the lengths of the superior and inferior aspects of the popliteal hiatus will help to further refine characterization of tears extending into the popliteal hiatus and to avoid potential overconstraint of the more mobile lateral meniscus during a repair by anatomically reproducing its native structural attachments.