Arthroscopic loose body removal and cyst decompression using a posterior trans-septal portal in the blind spot during knee arthroscopy--technical report

Effectiveness of arthroscopic excision based on the distribution of the tenosynovial giant cell tumor around knee joint

BACKGROUND

The mainstay treatment for tenosynovial giant cell tumor (TGCT) is open excision. However, open excision is associated with the risk of stiffness, infection, neurovascular injury, and prolonged hospital stay and rehabilitation. The purpose of this study was to evaluate the efficacy of arthroscopic excision of tenosynovial giant cell tumor (TGCT) of the knee joint, including the diffuse type of TGCT.

METHODS

Patients who underwent arthroscopic excision of TGCT between April 2014 and November 2020 were retrospectively analyzed. TGCT lesions were divided into 12 distributions (nine intra- and three extra-articular lesions). The distribution of TGCT lesions, portals used, degree of excision, recurrence, and magnetic resonance imaging (MRI) scans were evaluated. The prevalence of intra-articular lesions in diffuse TGCT was also analyzed to validate the existence of a connection between intra- and extra-articular lesions.

RESULTS

Twenty-nine patients were included in the study. Fifteen patients (52%) had localized TGCT, and 14 patients (48%) had diffuse TGCT. The recurrence rates for localized, and diffuse TGCT were 0%, and 7%, respectively. Intra-articular posteromedial (i-PM), intra-articular posterolateral (i-PL), and extra-articular posterolateral (e-PL) lesions were found in all patients with diffuse TGCT. The prevalence rates of i-PM and i-PL lesions among e-PL lesions were both 100% (p = 0.026 and p < 0.001, respectively). Diffuse TGCT lesions were managed with posterolateral capsulotomy and viewed from the trans-septal portal.

CONCLUSIONS

Arthroscopic excision of TGCT was effective in both localized and diffuse TGCT. However, diffuse TGCT was associated with posterior and extra-articular lesions. Therefore, technical modification such as posterior, trans-septal portal, and capsulotomy were required.

STUDY DESIGN

Retrospective case series; level Ⅳ.

Arthroscopic Identification of the Knee Posterolateral Corner Structures and Anatomic Arthroscopic Posterolateral Corner Reconstruction: Technical Note - Part 1

Arthroscopic assessment of posterior compartments of the knee and the posterior aspect of the proximal tibial and fibula is challenging because of the relative proximity of the neurovascular bundle. This Technical Note describes a reproducible arthroscopic surgical approach in a cadaveric model that aims to identify and expose the popliteus tendon, posterior fibular head, fibular collateral ligament popliteal fibular ligament, biceps femoris tendon, and peroneal nerve.

Arthroscopic removal of loose bodies using the accessory portals in the difficult locations of the knee: a case series and technical note

Background

It is often technically demanding to find and remove loose bodies in several difficult locations like the popliteus hiatus and posterior compartment arthroscopically. We aim to present the technical aspects of establishing some special accessory portals to achieve arthroscopic removal of the loose bodies in these locations.

Methods

From September 2010 to July 2017, 76 patients underwent removal of loose bodies in the popliteus hiatus and posterior compartment arthroscopically using some special accessory portal techniques. An auxiliary extreme lateral approach was established to remove loose bodies in the popliteus hiatus; a double-posteromedial portal was applied to handle loose body removal in the posteromedial compartment, and the posterior trans-septal portal was needed for loose body removal in the posterolateral compartment. Functional outcomes were evaluated using Lysholm score, Tegner score, and International Knee Documentation Committee (IKDC) score, respectively.

Results

Seventy-six patients (24 males and 52 females, average age 54.9 ± 11.4) finished the follow-up visit at 3 weeks after surgery. There was no statistically significant difference among the three groups in demographics. All the patients were performed following the special technique. According to a comparison of knee joint scores before and after surgery, all the patients obtained good prognosis using some special accessory portals in loose body removal.

Conclusions

With the help of the above accessory portals under endoscopic visualization, loose bodies in the popliteus hiatus and posterior compartment of the knee can be safely and effectively removed.

Posterior Knee Loose Bodies: Treated by Posterior Knee Arthroscopy

Introduction:

The posterior portion of the knee joint, which includes the tibial attachment of the posterior cruciate ligament and the posterior horn of the menisci, has been called a “blind spot” because it is difficult to observe this area under arthroscopy through standard anterior portals. Posteromedial, posterolateral, and posterior transseptal portals have been developed for visualization and instrumentation of the posteromedial and posterolateral compartments of the knee joint.

Case Report:

A 57-year-old man presented of persistent left posterior knee pain for 1 year. Radiographs and magnetic resonance imaging showed posterior knee encapsulated loose bodies. The symptoms did not respond to physiotherapy and analgesics. The loose bodies were removed via posterior knee arthroscopy. The symptoms subsided afterward.

Conclusion:

Lateral portal of the knee allows establishment of the posterolateral portal under endoscopic visualization, and the loose bodies of the posterior compartment of the knee can be effectively removed via the posterior knee arthroscopy.

Complete Arthroscopic Synovectomy in Management of Recalcitrant Septic Arthritis of the Knee Joint

Septic arthritis of the knee is a potentially life-threatening condition and can be associated with many late complications. The key of success of management of septic arthritis of the knee joint is early aggressive treatment of surgical debridement and decompression and antibiotic therapy. In adults, arthroscopic drainage with synovectomy is the treatment of choice in septic arthritis of the knee, with lower rates of infectious recurrence than needle aspiration and better functional results than open surgery. Repeated arthroscopic debridement and drainage is needed in case of delayed treatment with an advanced arthroscopic stage of the infection, early unfavorable course, or multiresistant germ. In these situations, synovectomy should be as complete as possible to maximize the reduction of the bacterial burden and avoid the need of further debridement. The purpose of this Technical Note is to describe the details of complete arthroscopic synovectomy of the knee joint. This includes 2 circles of circumferential synovectomy. One circle is in the axial plane and includes the intercondylar notch, anterior, posterior, medial, and lateral compartments. The other circle is in the coronal plane and includes the supra-patellar pouch, medial and lateral recesses, and the anterior compartment.

Accuracy and Reproducibility of the Femoral Tunnel With Different Viewing Techniques in the ACL Reconstruction

The purpose of this study was to compare the accuracy and reproducibility of the femoral tunnel location among 3 different viewing techniques used during outside-in anterior cruciate ligament (ACL) reconstruction with 3- dimensional (3-D) computed tomography (CT): (1) an anterolateral (AL) or anteromedial (AM) portal with a 30° arthroscope (A group) vs (2) a posterolateral (PL) portal with a 70° arthroscope (PL group) vs (3) a trans-septal (TS) portal with a 30° arthroscope (TS group). A total of 106 patients undergoing outside-in ACL reconstruction were recruited. Patients were divided into 3 groups according to viewing technique (A group=36 patients; PL group=35 patients; TS group=35 patients). Femoral tunnel locations were evaluated with the quadrant method and the anatomic coordinate axes measurement (ACAM) method in the medial wall of the lateral femoral condyle using 3-D reconstructed CT. The accuracy and reproducibility of the femoral tunnel locations were compared among the 3 techniques. The accuracy of the tunnel location was higher in the TS group by the quadrant method as well as the ACAM method. The reproducibility of the femoral tunnel position in the TS group was the highest, and the femoral tunnel locations of the TS group were more compactly distributed compared with those of the A and PL groups. The accuracy and reproducibility of the femoral tunnel location could be improved with a TS portal viewed using a 30° arthroscope. Anteromedial/anterolateral and PL portals viewed using a 70° arthroscope showed no difference. [Orthopedics. 2016; 39(6):e1085-e1091.].

Femoral Footprint Reconstruction With a Direct Viewing of the Posterior Insertion Using a Trans-Septal Portal in the Outside-In Anterior Cruciate Ligament Reconstruction

We established a technique for femoral tunnel preparation through direct vision of the femoral footprint with maximum preservation to the native anterior cruciate ligament (ACL) remnant using a posterior trans-septal portal. Anterior arthroscopy is difficult for the proper tunnel placement without sacrificing the ACL remnant. Posterior arthroscopy could be helpful for viewing the posterior insertion of the ACL remnant that provides excellent femoral footprint exposure without sacrificing the native ACL remnant. Therefore, a posterolateral portal technique using a 70° arthroscope through a posterolateral portal is introduced. However, using the 70° arthroscope, an oblique view is displayed and distorted view could be seen. Therefore, to achieve the goal of posterior arthroscopy and avoid obstacles of the posterolateral view with the 70° arthroscope, we introduce this technique that uses the posterior trans-septal portal with a 30° arthroscope that provides an excellent viewing to the femoral footprint through a hole of the posterior septum.

Arthroscopic approach to the posterior compartment of the knee using a posterior transseptal portal

Arthroscopic surgery of the posterior compartment of the knee is difficult when only two anterior portals are used for access because of the inaccessibility of the back of the knee. Since its introduction, the posterior transseptal portal has been widely employed to access lesions in the posterior compartment. However, special care should be taken to avoid neurovascular injuries around the posteromedial, posterolateral, and transseptal portals. Most importantly, popliteal vessel injury should be avoided when creating and using the transseptal portal during surgery. Purpose of the present study is to describe how to avoid the neurovascular injuries during establishing the posterior three portals and to introduce our safer technique to create the transseptal portal. To date, we have performed arthroscopic surgeries via the transseptal portal in the posterior compartments of 161 knees and have not encountered nerve or vascular injury. In our procedure, the posterior septum is perforated with a 1.5-3.0-mm Kirschner wire that is protected by a sheath inserted from the posterolateral portal and monitored from the posteromedial portal to avoid popliteal vessel injury.

Creation of an anatomic femoral tunnel with minimal damage to the remnant bundle in remnant-preserving anterior cruciate ligament reconstruction using an outside-in technique

We established a method for creation of an anatomic femoral tunnel with minimal damage to the remnant bundle in remnant-preserving anterior cruciate ligament (ACL) reconstruction. The goals of this surgical technique were to preserve the remnant bundle as much as possible, especially at the femoral insertion, and to make the tunnel at the anatomic position. The critical points are that the posterior side of the femoral footprint of the ACL is observed through the posterolateral portal using a 70° arthroscope and a femoral tunnel is made by use of an outside-in technique with remnant preservation. This technique allows for easy viewing of the posterior side of the ACL and enables performance of an anatomic ACL reconstruction.

Neurovascular anatomic relationships to arthroscopic posterior and transseptal portals in different knee positions

BACKGROUND

No study exists that directly measures the distances between posterior portals and the popliteal artery under arthroscopic conditions.

PURPOSE

To define the anatomic relationship between the neural structures and standard posterior arthroscopic portals and between the popliteal artery and posterior as well as transseptal portals in different knee positions.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Seventeen fresh-frozen cadaveric knees were used. The posterolateral, posteromedial, and transseptal portals were established at 90° of knee flexion. The popliteal artery was revealed using a shaver placed through the posteromedial portal. The distance from those portals to the popliteal artery was measured using a precision caliper. After the measurements were made, each specimen was dissected. The distance from a needle, blade, and cannula in each portal site to the adjacent neural structures was successively measured at 30°, 90°, and 120° of knee flexion.

RESULTS

The mean distance (in millimeters) from the posterolateral, posteromedial, and transseptal portals to the popliteal artery was significantly smaller at 30° (32.1 ± 4.6, 36.5 ± 4.9, and 9.0 ± 3.9, respectively) than at 90° (40.7 ± 5.1, 41.0 ± 3.8, and 18.0 ± 3.8, respectively) and 120° (38.4 ± 4.8, 38.7 ± 6.0, and 21.0 ± 4.0, respectively) of knee flexion. The mean distance from the posterolateral portal to the common peroneal nerve at 90° of flexion (needle, 26.6 ± 9.5; blade, 24.7 ± 6.9; cannula, 22.1 ± 6.9) was significantly greater than the distance at 30° (needle, 23.4 ± 6.5; blade, 21.4 ± 6.4; cannula, 18.4 ± 6.3) and 120° (needle, 21.8 ± 6.6; blade, 19.1 ± 6.3; cannula, 17.4 ± 6.7) of knee flexion. The mean distance between the posteromedial portal and the inferior infrapatellar branch of the saphenous nerve at 30° (needle, 18.6 ± 4.3; blade, 15.5 ± 3.3; cannula, 13.7 ± 5.8) of flexion was smaller than at 90° (needle, 20.1 ± 6.1; blade, 16.5 ± 5.3; cannula, 14.3 ± 4.4) and 120° (needle, 21.1 ± 3.6; blade, 17.7 ± 4.9; cannula, 15.1 ± 5.9) of flexion, but there was no statistical significance. The mean distance from the posteromedial portal to the sartorial branch of the saphenous nerve at 30° (needle, 22.8 ± 6.1; blade, 19.8 ± 5.3; cannula, 17.7 ± 6.2) of flexion was significantly smaller than that at 90° (needle, 29.7 ± 3.6; blade, 26.3 ± 6.3; cannula, 23.1 ± 4.7) and 120° (needle, 31.5 ± 3.9; blade, 28.9 ± 4.1; cannula, 25.4 ± 5.1) of flexion. Conclusion/

CLINICAL RELEVANCE

The position of 90° of knee flexion is safe to establish posterior and transseptal arthroscopic portals. The position of 120° of knee flexion is practically safe to establish posteromedial and transseptal portals, but it is unsafe to create a posterolateral portal because the risk of damaging the common peroneal nerve is high. The position of 30° of knee flexion is not recommended to establish posterior arthroscopic portals.

Arthroscopic partial meniscectomy of a posteriorly flipped superior leaflet in a horizontal medial meniscus tear using a posterior transseptal portal

This article describes a case of an arthroscopic partial meniscectomy of a posteriorly flipped superior leaflet in a horizontal medial meniscus tear using the posterior transseptal portal. An arthroscopic partial meniscectomy for bucket handle or flap tears in medial or lateral compartments using ordinary portals is a relatively common procedure in irreparable cases. However, the posterior compartment of the knee is not readily accessible through ordinary arthroscopic portals. Therefore, it has been considered a blind spot. Through the posterior transseptal portal, surgeons can achieve excellent arthroscopic visualization of the posterior compartment and easily perform arthroscopic procedures of the posterior compartment of the knee. A 48-year-old woman presented with a 1-year history of pain in the medial aspect of the right knee joint. Preoperative magnetic resonance imaging revealed a thinning of the medial meniscus posterior horn in coronal images and a sharp-edged triangle arising from the medial meniscus posterior horn between the medial femoral condyle and medial meniscus posterior horn on sagittal images (flipped-over sign). During the arthroscopic procedure, we found that the flipped leaflet was displaced posteriorly and was not mobile between the medial femoral condyle and medial meniscus posterior horn. Partial meniscectomy for a posteriorly displaced fragment can be performed successfully using the posterior transseptal portal. The posterior transseptal portal is useful for an arthroscopic partial meniscectomy of a posteriorly flipped leaflet in the posterior compartment of the knee.