How to avoid collision between PCL and MCL femoral tunnels during a simultaneous reconstruction

Maximum outcome with minimal resources: report of a multiligamentous knee injury managed with 'modified confluent tunnel technique'

Multiligamentous knee injuries (MLKIs) are rare and challenging to manage in many aspects. The injury requires prompt diagnosis, reconstruction of multiple ligaments, and management of associated neurovascular injuries. Another important aspect that surgeons should consider is resource availability. Successful management of a case of MLKI using the cost-effective 'modified confluent tunnel technique' is described in this case report. We used confluent tunnels for intra- and extra-articular ligament reconstructions at the femoral side. We incorporated the weave technique for medial collateral ligament (MCL) reconstruction, and Larson's technique for posterolateral corner (PLC) reconstruction in this construct, and augmented the anterior cruciate ligament (ACL) and posterior cruciate ligament reconstruction with the remaining PLC and MCL grafts, respectively. This was cost-effective and resulted in good functional outcomes. The technique also helped us to avoid tunnel convergence which is an expected complication in MLKI surgeries.

Reduction of Collision Risk in Multi-ligament Knee Injury KD-III-M and KD-IV Surgery-Superficial Medial Collateral Ligament Reconstruction with Suture Anchors

Surgical reconstruction of the medial collateral ligament (MCL) can be challenging during multi-ligament knee injury surgery due to the limited working space. There is risk of collision between the guide pin, pulling sutures, reamer, tunnel, implant, and graft of the different ligament reconstructions. In this Technical Note, we detail our senior author's technique for superficial MCL reconstruction using suture anchors and cruciate ligament reconstruction with all-inside techniques. The technique mitigates the risk of collision by confining the reconstruction process and implants for MCL fixation on the medial femoral condyle and medial proximal tibia.

Three-dimensional-printed patient-specific instrumentation is an accurate tool to reproduce femoral bone tunnels in multiple-ligament knee injuries

PURPOSE

Multiple-ligament knee reconstruction techniques often involve the creation of several bone tunnels for various reconstruction grafts. A critical step in this procedure is to avoid short tunnels or convergences among them. Currently, no specific template guide to reproduce these angulations has been reported in the literature, and the success of the technique still depends on the experience of the surgeon. The aim of this study is to analyze the accuracy and reliability of 3D-printed patient-specific instrumentation (PSI) for lateral and medial anatomical knee reconstructions.

METHODS

Ten cadaveric knees were scanned by computed tomography (CT). Using specific computer software, anatomical femoral attachments were identified: (1) on the lateral side the lateral collateral ligament (LCL) and the popliteal tendon (PT) and (2) on the medial side the medial collateral ligament (MCL) and the posterior oblique ligament (POL). Four bone tunnels were planned for each knee, and PSI with different directions were designed as templates to reproduce the planned tunnels during surgery. Twenty 3D-printed PSI were used: ten were tailored to the medial side for reconstructing MCL and POL tunnels, and the other ten were tailored to the lateral side for reconstructing LCL and PT tunnels. Postoperative CT scans were made for each cadaveric knee. The accuracy of the use of 3D-printed PSI was assessed by superimposing post-operative CT images onto pre-operative images and analyzing the deviation of tunnels performed based on the planning, specifically the entry point and the angular deviations.

RESULTS

The median entry point deviations for the tunnels were as follows: LCL tunnel, 1.88 mm (interquartile range (IQR) 2.2 mm); PT tunnel, 2.93 mm (IQR 1.17 mm); MCL tunnel, 1.93 mm (IQR 4.26 mm); and POL tunnel, 2.16 mm (IQR 2.39). The median angular deviations for the tunnels were as follows: LCL tunnel, 2.42° (IQR 6.49°); PT tunnel, 4.15° (IQR 6.68); MCL tunnel, 4.50° (IQR 6.34°); and POL tunnel, 4.69° (IQR 3.1°). No statistically significant differences were found in either the entry point or the angular deviation among the different bone tunnels.

CONCLUSION

The use of 3D-printed PSI for lateral and medial anatomical knee reconstructions provides accurate and reproducible results and may be a promising tool for use in clinical practice.

Modified Bosworth Technique for Medial Collateral Ligament Reconstruction of the Knee Using Semitendinosus Tendon Autograft

The medial collateral ligament (MCL) is a major contributor to knee joint stability and is the most common ligament involved in knee injuries. When conservative management for high-grade MCL injuries fails, operative treatment is indicated. Various reconstruction techniques are described in the literature. The following report describes a reconstruction technique based on the modified Bosworth. We present a step-by-step technique for using autograft semitendinosus tendon as a double limb to reconstruct the MCL and if necessary, the posterior oblique ligament. The technique is versatile with respect to a spectrum of MCL injury patterns, isometric, incorporates techniques that are common to other knee reconstructions, and uses readily available autograft. It has been used extensively by the senior authors as an adjunct/augmentation to the repair of acute MCL injuries as well as in the reconstruction of chronic MCL laxity. The technique restores stability to rotation and valgus stress while maintaining the distal insertion of the semitendinosus intact.

Bone Staples Provide Favorable Primary Stability in Cortical Fixation of Tendon Grafts for Medial Collateral Ligament Reconstruction: A Biomechanical Study

Background:

The use of the interference screw (IFS) for the cortical fixation of tendon grafts in knee ligament reconstruction may lead to converging tunnels in the multiligament reconstruction setting. It is unknown whether alternative techniques using modern suture anchor (SA) or bone staple (BS) fixation provide sufficient primary stability.

Purpose:

To assess the primary stability of cortical fixation of tendon grafts for medial collateral ligament (MCL) reconstruction using modern SA and BS methods in comparison with IFS fixation.

Study Design:

Controlled laboratory study.

Methods:

Cortical tendon graft fixation was performed in a porcine knee model at the tibial insertion area of the MCL using 3 different techniques: IFS (n = 10), SA (n = 10), and BS (n = 10). Specimens were mounted in a materials testing machine, and cyclic loading for 1000 cycles at up to 100 N was applied to the tendon graft, followed by load-to-failure testing. Statistical analysis was performed using 1-way analysis of variance.

Results:

There were no statistical differences in elongation during cyclic loading or peak failure load during load-to-failure testing between BS (mean ± standard deviation: 3.4 ± 1.0 mm and 376 ± 120 N, respectively) and IFS fixation (3.9 ± 1.2 mm and 313 ± 99.5 N, respectively). SA fixation was found to have significantly more elongation during cyclic loading (6.4 ± 0.9 mm; P < .0001) compared with BS and IFS fixation and lower peak failure load during ultimate failure testing (228 ± 49.0 N; P < .01) compared with BS fixation.

Conclusion:

BS and IFS fixation provided comparable primary stability in the cortical fixation of tendon grafts in MCL reconstruction, whereas a single SA fixation led to increased elongation with physiologic loads. However, load to failure of all 3 fixation techniques exceeded the loads expected to occur in the native MCL.

Clinical Relevance:

The use of BS as a reliable alternative to IFS fixation for peripheral ligament reconstruction in knee surgery can help to avoid the conflict of converging tunnels.

Surgical Treatment of Combined ACL PCL Medial Side Injuries

The multiple ligament knee injury involving the medial collateral ligament, anterior cruciate ligament, and posterior cruciate ligament is typically the result of a high-energy trauma or knee dislocation event. Optimal treatment strategies are debated, specifically in regard to timing of surgery, reconstruction/repair techniques, and postoperative protocols. This review details the stepwise treatment of these complex patients from diagnosis to postoperative rehabilitation and summarizes the current literature.

Safe drilling angles avoid femoral tunnel complications during combined anterolateral ligament and anterior cruciate ligament reconstruction

PURPOSE

To determine the best angle to drill the femoral tunnels of an anterolateral ligament (ALL) anatomic reconstruction combined with a single-bundle anterior cruciate ligament (ACL) reconstruction to avoid tunnel collisions and cortical disruption.

METHODS

Ten cadaveric knees were studied. Single-bundle anatomic ACL femoral tunnels were arthroscopically drilled. The starting point of the ALL femoral tunnel was located posterior and superior to the lateral epicondyle. ALL tunnels were drilled at four different angulations: (1) 0° axial/0° coronal, (2) 0° axial/30° coronal superior, (3) 30° axial anterior/0° coronal, and (4) 30° axial anterior 30° coronal superior. Specimens were scanned by computed tomography to measure the relations of each trajectory with the ACL socket and the nearest cortical bone.

RESULTS

None of the four trajectories studied presented risk of collision with the ACL. The tunnel at 30° anterior/30° proximal presented the safest distance to the ACL socket (P = 0.01) [mean distance 18.6 mm (SD ± 6.7)]. However, both tunnels angled at 0° in the axial plane presented a high risk of posterior femoral cortex disruption (P = 0.01), either by close proximity or direct contact in some specimens (mean distance 3.1 mm (SD ± 2.8) at 0° axial/0° coronal and 3.7 mm (SD ± 2.2) at 0° axial/30° coronal).

CONCLUSIONS

When performing simultaneous ACL and ALL ligament reconstruction, the ALL femoral tunnel should be drilled with an angle of 30° anterior in the axial plane and 30° proximal in the coronal plane. Tunnels with an angle of 0° in the axial plane showed high risk of contact and disruption of the posterior femoral cortex; thus, these angles should be avoided. The clinical relevance of this work is that an ALL anatomical reconstruction does not represent a risk when performing a simultaneous ACL reconstruction as long as the ALL tunnel is reamed with a proximal and anterior angulation.

Combined Posterior Cruciate Ligament and Superficial Medial Collateral Ligament Knee Reconstruction: Avoiding Tunnel Convergence

Combined posterior cruciate ligament (PCL) and medial collateral ligament (MCL) injuries represent a complex pathology that requires a thorough clinical and radiographic examination to diagnose and identify all injured structures. Anatomic reconstruction of the injured ligaments is recommended, including double-bundle PCL reconstruction and superficial MCL augmentation. In the setting of this complex reconstruction, several technical aspects require consideration and preoperative planning, including the risk of femoral tunnel convergence on the medial aspect of the femoral condyle. This article details our technique for combined anatomic double-bundle PCL reconstruction and superficial MCL augmentation to avoid tunnel convergence. Level I (knee); level II (PCL).

Combined reconstruction of the posterior cruciate ligament and medial collateral ligament using a single femoral tunnel

PURPOSE

Lesions of the medial collateral ligament (MCL) are the most common knee ligament injuries, and lesions associated with the anterior cruciate ligament or the posterior cruciate ligament (PCL) in knee dislocations should be reconstructed to prevent failure of the central pivot reconstruction. The purpose of this study was to evaluate the outcomes of combined PCL/MCL reconstruction using a single femoral tunnel with a minimum 2-year follow-up.

METHOD

A retrospective study of thirteen patients with combined PCL/MCL injuries was conducted. The patients underwent PCL and MCL reconstruction using an Achilles tendon allograft with a single tunnel in the medial femoral condyle, thereby avoiding tunnel conversion.

RESULTS

All patients achieved a range of motion of at least 100°. The mean loss of extension and flexion values compared to the contralateral side was 1° ± 2° and 9° ± 10°, respectively. Our results included 26 reconstructions with three (11.5 %) failures, two in the PCL (15.3 %) and one in the MCL (7.6 %), in three different patients. In the final evaluation, the mean IKDC subjective score was 71.63 ± 16.23, the mean Lysholm score was 80.08 ± 13.87, and the median Tegner score was 6 (range = 2-7).

CONCLUSION

The PCL/MCL reconstruction technique using a single femoral tunnel and an Achilles tendon allograft is safe, avoids the convergence of tunnels in the medial femoral condyle, has excellent results, and is reproducible.

LEVEL OF EVIDENCE

IV.

Multiligament Reconstruction of the Knee in the Setting of Knee Dislocation With a Medial-Sided Injury

Multiple ligament knee injuries are complex pathologies that often result from traumatic knee dislocations. Both a high level of suspicion and a thorough clinical and radiographic examination are mandatory to diagnose and identify all injured structures. Reconstruction of all injured ligaments is recommended to aid in early mobilization and to avoid joint stiffness or graft failure. For knee dislocations involving injury to the anterior cruciate ligament, posterior cruciate ligament, and medial-sided structures, a repair and augmentation of the medial collateral ligament, together with an anatomic reconstruction of the anterior cruciate ligament and double-bundle posterior cruciate ligament, is recommended. In the setting of these complex reconstructions, there are several technical aspects that require consideration to ensure concise and efficient treatment of these injuries. Graft choice, sequence of reconstruction, tunnel position and orientation, and graft tensioning all pose surgical challenges, and require dedicated preoperative preparation and planning. The purpose of this Technical Note is to report a safe, effective, and reproducible surgical technique for treatment of multiligament injuries in the setting of a knee dislocation with a medial-sided component (classified as KD-III-M in the Schenck classification system).

Multiple Ligament Reconstruction Femoral Tunnels: Intertunnel Relationships and Guidelines to Avoid Convergence

BACKGROUND

Knee dislocations often require multiple concurrent ligament reconstructions, which involve creating several tunnels in the distal femur. Therefore, the risk of tunnel convergence is increased because of the limited bone volume within the distal aspect of the femur.

PURPOSE

To assess the risk of tunnel convergence and determine the optimal reconstruction tunnel orientations for multiple ligament reconstructions in the femur.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Three-dimensional knee models were developed from computed tomography scans of 21 patients. Medical image processing software was used to create tunnels for each of the primary ligamentous structures, replicating a surgical approach that would be used in multiple ligament reconstructions. Thereafter, the tunnel orientation was varied in surgically relevant directions to determine orientations that minimized the risk of tunnel convergence. The orientation of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tunnels was held constant throughout the study, while the orientation of the fibular collateral ligament (FCL), popliteus tendon (PLT), superficial medial collateral ligament (sMCL), and posterior oblique ligament (POL) tunnels was varied to avoid convergence.

RESULTS

A high risk of tunnel convergence was observed between the FCL and ACL tunnels when the FCL tunnel was aimed at 0° in the axial and coronal planes. Aiming the FCL tunnel 35° anteriorly minimized convergence with the ACL tunnel. No tunnel convergence was observed for the PLT tunnel aimed 35° anteriorly and parallel to the FCL tunnel. To avoid convergence between the sMCL and PCL tunnels, the sMCL tunnels should be aimed 40° proximally in the coronal plane and 20° to 40° anteriorly. During concomitant POL reconstruction, the sMCL should be aimed 40° proximally and anteriorly and the POL 20° proximally and anteriorly. The PLT and POL tunnels aimed at 0° in both the coronal and axial planes had an increased risk of violating the intercondylar notch.

CONCLUSION

Femoral tunnel orientations during multiple ligament reconstructions need to be adjusted to avoid tunnel convergence. On the lateral side, aiming the FCL and PLT tunnels 35° anteriorly eliminated convergence with the ACL tunnel. On the medial side, tunnel convergence was avoided by orienting the sMCL tunnel 40° proximally and anteriorly and the POL tunnel 20° proximally and anteriorly. The POL and PLT tunnels aimed at 0° in the axial plane had an increased risk of violating the intercondylar notch.

CLINICAL RELEVANCE

The risk of tunnel convergence with the ACL and PCL femoral tunnels can be reduced by adjusting the orientation of the FCL and PLT tunnels and the sMCL and POL tunnels, respectively.

Medial collateral ligament reconstruction using bone-patellar tendon-bone allograft for chronic medial knee instability combined with multi-ligament injuries: a new technique

BACKGROUND

The medial collateral ligament (MCL) is the main static stabilizer of the medial knee. The surgical treatment was recommended in cases with serious medial collateral ligament insufficiency combined with multi-ligament injuries and chronic symptomatic medial instability. Several surgical techniques have been described for the MCL reconstruction, while potential problems including donor site morbidity, complicated procedure, and high risk of femoral tunnel collision were reported. In order to minimize such potential limitations, we describe a new medial reconstruction technique for MCL injury using bone-patellar tendon-bone (BPTB) allograft.

METHODS

A longitudinal incision at the medial knee was made. The centers of femoral and tibial attachments were gained through repeated isometricity test. Then, the bone grooves were made around the femoral and tibial centers. The appropriate BPTB allograft was selected, and both ends were trimmed. The prepared bone blocks were embedded into the grooves and fixed with cancellous screws. The programmed rehabilitation exercises were performed after the operation.

RESULTS

A strong graft and bone-to-bone healing on both femoral and tibial attachment sites were obtained, and femoral tunnel collision during multi-ligament reconstruction was avoided. Satisfactory valgus and rotatory stability were gained.

CONCLUSIONS

This novel MCL reconstruction technique using BPTB allograft can be safely performed, and the clinical outcome was favorable with satisfactory valgus and rotatory stability. More cases and additional follow-up results are needed to verify the overall effect of this technique.