Estudo anatômico da inserção dos tendões flexores do joelho

The Presence of a 'Sentinel' Vessel as an Anatomical Reference during Hamstring Tendon Harvesting-A Prospective Study

BACKGROUND

The identification of the branch of the inferior medial genicular artery (bIMGA) in anterior cruciate ligament reconstructions (ACLRs) has previously been considered a landmark by some surgeons, but its consistency remains debated. The aim of this investigation was to evaluate the variability in the appearance and location of bIMGA and to assess its validity as a reliable landmark during hamstring tendon harvesting procedures.

METHODS

This prospective, single-center study comprised 213 patients who underwent ACLR over a period of two years. The surgical procedures were conducted by the same surgical team, maintaining uniformity in the approach. The study sought correlations between patient demographics, level of activity, and the potential for successful identification of the bIMGA.

RESULTS

A statistically significant association between patient activity levels and successful identification of the bIMGA (p = 0.035) was observed. No significant correlations were found concerning patient demographic characteristics. bIMGA demonstrated a substantial degree of anatomical variability, rendering its consistent identification in the surgical field challenging.

CONCLUSIONS

Given the observed variability and the associated difficulty in its identification, the use of the bIMGA as a dependable anatomical reference during ACL graft harvesting is not recommended. This study confirms the inconsistency of bIMGA as a traditional landmark, underscoring the need for research aimed at identifying more consistent and reliable anatomical references to enhance the precision of surgical interventions in ACLR.

Ultrasound Imaging in Predicting the Autograft Size in Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis

Anterior cruciate ligament (ACL) reconstruction is widely used to restore knee stability after injury, but the risk of revision surgery increases when the autograft size is inadequate. Ultrasound (US) measurements of preoperative target tendons have been applied to predict the intraoperative autograft size, with various outcomes across different studies. This systematic review and meta-analysis aimed to summarize the evidence and investigate the usefulness of US in predicting autograft size. Electronic databases were searched for relevant studies from inception to 19 January 2022. The primary outcome was the correlation between the preoperative US measurements of donor tendons and intraoperative autograft size. The secondary outcomes encompassed the predictive performance of US for autograft size and the comparison between US and magnetic resonance imaging (MRI) for preoperative tendon measurements. Nine studies, comprising 249 patients, were enrolled. The preoperative US measurements of the donor tendons demonstrated a significant positive correlation with their intraoperative autograft diameter, with a pooled correlation coefficient of 0.443 (95% confidence interval [CI], 0.266−0.591, p < 0.001) for the gracilis and semitendinosus autograft, 0.525 (95% CI, 0.114−0.783, p = 0.015) for the semitendinosus autograft, and 0.475 (95% CI, 0.187−0.687, p = 0.002) for the gracilis autograft. The pooled sensitivity and specificity of US imaging in predicting the autograft diameter were 0.83 (95% CI 0.57−0.95) and 0.70 (95% CI, 0.36−0.91), respectively. Moreover, no significant differences were observed between US and MRI measurements in predicting the sizes of the gracilis and semitendinosus autografts. Preoperative US measurements of the target tendons were moderately correlated with the intraoperative autograft size. US imaging has a discriminative performance similar to that of MRI in predicting the autograft size. A standardized US scanning protocol is needed for future studies to minimize the variations in tendon measurements across different investigators and increase the comparability of US imaging with intraoperative findings.

Inferior Medial Geniculate Artery Branch as an Anatomical Landmark for Hamstring Harvest During Anterior Cruciate Ligament Reconstruction

Graft harvesting is often a challenging step of anterior cruciate ligament reconstructions. Accurate isolation of the hamstring tendons at the pes anserinus is crucial to successful graft harvesting. We describe a technique of using a branch of the inferior medial geniculate artery overlying the pes anserinus insertion as an anatomical landmark to localize the hamstring tendons for harvest. By using this vessel as an anatomical landmark, the incision length was decreased and the time required to harvest reduced. This is a highly reproducible technique and will be beneficial for soft tissue harvesting surgeons to ease hamstring graft harvesting.

Concepts of the Distal Medial Patellar Restraints: Medial Patellotibial Ligament and Medial Patellomeniscal Ligament

The important medial patellar ligamentous restraints to lateral dislocation are the proximal group (the medial quadriceps tendon femoral ligament and the medial patellofemoral ligament) and the distal group [medial patellotibial ligament (MPTL) and medial patellomeniscal ligament (MPML)]. The MPTL patellar insertion is at inferomedial border of patella and tibial insertion is in the anteromedial tibia. The MPML originates in the inferomedial patella, right proximal to the MPTL, inserting in the medial meniscus. On the basis of anatomy and biomechanical studies, the MPTL and MPML are more important in 2 moments during knee range of motion: terminal extension, when it directly counteracts quadriceps contraction. In a systematic review on MPTL reconstructions 19 articles were included detailing the clinical outcomes of 403 knees. All were case series. Overall, good and excellent outcomes were achieved in >75% of cohorts in most studies and redislocations were <10%, with or without the association of the medial patellofemoral ligament. The MPTL is a relevant additional tool to proximal restraint reconstruction in select patient profiles; however, more definitive clinical studies are necessary to better define surgical indications.

Reconstruction of the medial patellotibial ligament results in favorable clinical outcomes: a systematic review

PURPOSE

The medial patellotibial ligament (MPTL), the medial patellofemoral ligament (MPFL), and the medial patellomeniscal ligament (MPML) support the stability of the patellofemoral joint. The purpose of this systematic review was to report the surgical techniques and clinical outcomes of the repair or reconstruction of the MPTL in isolation or concomitant with the MPFL and/or other procedures.

METHODS

A systematic review of the literature was conducted. Inclusion criteria were articles in the English language that reported clinical outcomes of the reconstruction of the MPTL in isolation or in combination with the MPFL and/or other procedures. Included articles were then cross-referenced to find additional journal articles not found in the initial search. The methodological quality of the articles was determined using the Coleman Methodology Score.

RESULTS

Nineteen articles were included detailing the clinical outcomes of 403 knees. The surgical procedures described included hamstrings tenodesis with or without other major procedures, medial transfer of the medial patellar tendon with or without other major procedures and the reconstruction of the MPTL in association with the MPFL. Overall, good and excellent outcomes were achieved in > 75% of cohorts in most studies and redislocations were < 10%, with or without the association of the MPFL. An exception was one study that reported a high failure rate of 82%. Results were consistent across different techniques. The median CMS for the articles was 66 out of 100 (range 30-85).

CONCLUSION

Across different techniques, the outcomes are good with low rates of recurrence, with one article reporting a high rate of recurrence. Quality of the articles is variable, from low to high. Randomized control trials are needed for a better understanding of the indications, surgical techniques, and clinical outcomes. This systematic review suggests that the reconstruction of the MPTL leads to favorable clinical outcomes and supports the role of the procedure as a valid surgical patellar stabilization procedure.

LEVEL OF EVIDENCE

IV: systematic review of level I-IV studies.

Medial patellotibial ligament and medial patellomeniscal ligament: anatomy, imaging, biomechanics, and clinical review

PURPOSE

The purpose of this article is to review anatomical, biomechanical, and clinical data of the medial patellotibial ligament (MPTL) and medial patellomeniscal ligament (MPML), as well as studies focusing on the medial patellofemoral ligament (MPFL) but with relevant data about the MPTL and MPML.

METHODS

A literature search of articles specifically addressing the MPTL and/or MPML was included along with studies focusing on the MPFL but with relevant data about the MPTL and MPML.

RESULTS

The medial patellar ligaments responsible for maintaining the stability of the patellofemoral (PF) joint include the MPFL, the MPTL, and the MPML. The MPFL is considered the primary restraint to lateral patellar translation, while the latter two are considered secondary restraints. There is robust literature on the anatomical, imaging, and biomechanical characteristics of the MPFL, and also the clinical outcome of its injury and surgical reconstruction; much less is known about the MPTL and MPML. Isolated MPFL reconstruction has good clinical and functional outcomes, with a low failure rate when defined as frank re-dislocation. Complications, including continued episodes of patellar apprehension and subluxation, remain present in most series. In addition, the current literature primarily includes a homogeneous population with few excessive anatomic dysplastic factors. There is lack of knowledge on the role of MPTL and MPML in (potentially) aiding patella stabilization and improving clinical outcomes. Understanding the role of the medial-sided patellar ligaments, in particular the role of the secondary stabilizers, in PF function and injury will aid in this goal.

CONCLUSION

MPTL and MPML have consistent basic science literature, as well as favorable clinical outcomes of surgical patellar stabilization with reconstruction of the MPTL. However, there is much heterogeneity among clinical case series and lack of comparative studies to allow clear indication for the role of isolated or combined surgical reconstruction in patellar stabilization. Therefore, this comprehensive review helps understand the current knowledge and the possible applications in the orthopedic clinical practice.

LEVEL OF EVIDENCE

V.

Medial Patellofemoral Ligament, Medial Patellotibial Ligament, and Medial Patellomeniscal Ligament: Anatomic, Histologic, Radiographic, and Biomechanical Study

PURPOSE

To describe the anatomy (quantitative macroscopic and histologic), radiographic parameters of the insertions, and biomechanical characteristics of the medial ligamentous restrictors of the patella (medial patellofemoral ligament [MPFL], medial patellotibial ligament [MPTL], and medial patellomeniscal ligament [MPML]) in cadaveric knees. Because the MPTL and the MPML are not as well known as the MPFL, they were the focus of this study.

METHODS

MPFLs, MPTLs, and MPMLs from 9 knees were dissected. Histologic evaluations were conducted. Length, width, and insertion relations with anatomic references were determined. Metallic spheres were introduced into the insertion points of each ligament, and anteroposterior and lateral radiographs were taken. The distances of the insertions from the baselines were measured on radiographs. Tensile tests of the ligaments were performed.

RESULTS

All the samples showed dense connective tissue characteristic of ligaments. The MPTL was inserted into the proximal tibia (13.7 mm distal to the joint line) and in the distal end of the patella (3.6 mm proximal to the distal border). The MPTL had a length of 36.4 mm and a width of 7.1 mm. The MPML was inserted into the medial meniscus and distally in the patella (5.7 mm proximal to the distal border). Per radiography, on the anteroposterior view, the tibial insertion of the MPTL was 9.4 mm distal to the joint line and in line with the medial border of the medial spine. On the lateral view, the patellar insertions of the MPTL and MPML were 4.8 and 6.6 mm proximal to its distal border, respectively. The MPTL was stiffer than the MPFL (17.0 N/mm vs 8.0 N/mm, P = .024) and showed less deformation in the maximum tensile strength (8.6 mm vs 19.3 mm, P = .005).

CONCLUSIONS

The MPTL inserts into the proximal tibia and into the distal pole of the patella. The MPML inserts into the medial meniscus and into the distal pole of the patella. They present with identifiable anatomic and radiographic parameters. Grafts commonly used for ligament reconstructions should be adequate for reconstruction of the MPTL.

CLINICAL RELEVANCE

The study contributes to the anatomic, radiographic, and biomechanical knowledge of the MPTL to improve the outcomes of its reconstruction.

Cadaveric study of the secondary medial patellar restraints: patellotibial and patellomeniscal ligaments

PURPOSE

To detail the anatomy of the medial patella stabilizers, medial patellotibial (MPTL), and medial patellomeniscal ligaments (MPML), focusing on the points of origin and insertion, length, thickness, width, and fibres orientation to study the frequency of anatomical variations and the anatomy of these ligaments, thereby improving surgical techniques.

METHODS

Thirty dissected knees were analysed. A digital caliper was used to measure the length, thickness, and width, as well as the mid-point of the ligaments insertion and the distance from the MPTL insertion to the articular surface of the tibia. The angle of inclination of the ligaments was calculated in the coronal plane. The collected data were tabulated and statistically analysed.

RESULTS

MPTL was present in 90 % as a visible thickening of the deep medial retinaculum and exhibiting only one anatomical variation. The MPML was absent in one of the dissected knees, and one anatomical variation was found. The tilt angle of the ligaments was very similar, with an average of 22.2° ± 7.6° for the MPTL and 24.2° ± 6.6° for the MPML.

CONCLUSION

The MPTL is a long visible structure of the deep layer of the medial retinaculum, but with a distinct origin and insertion. The MPML is thicker with an angular direction similar to MPTL. The presence of these ligaments in most of the specimens studied suggests that the real anatomical and biomechanical importance of these ligaments should be further investigated because they play a role in the patellar stability.

Combined Reconstruction of the Medial Patellofemoral Ligament With Quadricipital Tendon and the Medial Patellotibial Ligament With Patellar Tendon

Although the medial patellotibial ligament (MPTL) has been neglected regarding its function in patellar stability, recently, its importance in terminal extension and during flexion has been recognized. Indications for reconstruction of the medial patellofemoral ligament combined with the MPTL are extension subluxation, flexion instability, children with anatomic risk factors for patellar instability, and knee hyperextension associated with generalized laxity. We describe a combined reconstruction of the medial patellofemoral ligament with quadricipital tendon and reconstruction of the MPTL with patellar tendon autografts.

Reconstruction of medial patellofemoral ligament using quadriceps tendon combined with reconstruction of medial patellotibial ligament using patellar tendon: initial experience

OBJECTIVE

To describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series.

METHOD

The proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC-IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM), apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from 0 to 10) and whether they would be prepared to go through this operation again.

RESULTS

Seven knees were operated, in seven patients, with a mean follow-up of 5.46 months (±2.07). Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound.

CONCLUSION

Reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon, was technically safe and presented good objective and subjective clinical results in this case series with a short follow-up.