The Function of the Short Medial Collateral Ligaments of the Canine Tarsus: A Cadaveric Study

ABSTRACT Information on the clinical behavior of cases with an isolated rupture of the short collateral ligaments of the canine tarsus is sparse. Our objective was to evaluate the function of the short medial collateral ligaments (SMCLs) in 90° flexion. Eight cadaveric limbs were tested for internal/external rotation and valgus/varus before and after transection of one or both SMCLs. In one group, the tibiocentral ligament was transected first, followed by the tibiotalar. In the second group, the order of transection was reversed. Angular changes between two k-wires were measured and compared. Internal rotation increased significantly after transection of one or both SMCLs (P = .015 and P = .004), with higher angular changes in the group in which the tibiotalar ligament was transected first (P = .003). Transection of this ligament alone was sufficient to cause caudomedial subluxation upon internal rotation. Valgus angulation increased after transection of one ligament (P = .022), but there was also an increase in varus angulation after transection of both ligaments (P = .027). Unlike the long medial collateral ligament, which stabilizes against deviation toward lateral, the SMCL stabilizes against subluxation toward medial, with the tibiotalar ligament being the major stabilizer in flexion. Findings can be used as diagnostic guidance for isolated tarsal short collateral ligament injuries.

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The Function of the Short Lateral Collateral Ligaments of the Canine Tarsus: A Cadaveric Study

Journal of the American Animal Hospital Association ◽

10.5326/jaaha-ms-6819 ◽

2019 ◽

Vol 55 (5) ◽

pp. 220-225

Author(s):

Riccarda Schuenemann ◽

Sandra Bogisch

Keyword(s):

External Rotation ◽

Lateral Collateral Ligament ◽

Cadaveric Study ◽

Collateral Ligaments ◽

Collateral Ligament ◽

Clinical Behavior ◽

Before And After ◽

Lateral Subluxation ◽

Lateral Collateral Ligaments ◽

K Wires

ABSTRACT Information on the clinical behavior and treatment of cases with an isolated rupture of the short collateral ligaments of the canine tarsus is sparse and contradictory in the veterinary literature. Our objective was to evaluate the function of the short lateral collateral ligaments (SLCLs) of the tarsocrural joint in 90° flexion. Eight canine cadaveric limbs were tested for internal/external rotation and valgus/varus before and after transection of one or both SLCLs. In one group, the fibulocalcaneal ligament was transected first, followed by the fibulotalar. In the second group, the order of ligament transection was reversed. Angular changes between two k-wires were measured and compared. External rotation increased significantly after transection of one or both SLCLs (P = .009 and P < .0005), as did varus (P = .021 and P = .001). Lateral subluxation was only possible when both SLCLs were cut. Unlike the long lateral collateral ligament, which stabilizes against deviation toward medial, both SLCLs are major stabilizers against subluxation toward lateral. This important difference must be considered in clinical patients with isolated rupture of the SLCLs.

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Length-change patterns of the medial collateral ligament and posterior oblique ligament in relation to their function and surgery

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-020-06050-0 ◽

2020 ◽

Vol 28 (12) ◽

pp. 3720-3732 ◽

Cited By ~ 3

Author(s):

Lukas Willinger ◽

Shun Shinohara ◽

Kiron K. Athwal ◽

Simon Ball ◽

Andy Williams ◽

...

Keyword(s):

Internal Rotation ◽

Medial Collateral Ligament ◽

Knee Flexion ◽

External Rotation ◽

Length Change ◽

Linear Displacement ◽

Collateral Ligament ◽

Posterior Oblique Ligament ◽

Draw Force ◽

Length Changes

Abstract Purpose To define the length-change patterns of the superficial medial collateral ligament (sMCL), deep MCL (dMCL), and posterior oblique ligament (POL) across knee flexion and with applied anterior and rotational loads, and to relate these findings to their functions in knee stability and to surgical repair or reconstruction. Methods Ten cadaveric knees were mounted in a kinematics rig with loaded quadriceps, ITB, and hamstrings. Length changes of the anterior and posterior fibres of the sMCL, dMCL, and POL were recorded from 0° to 100° flexion by use of a linear displacement transducer and normalised to lengths at 0° flexion. Measurements were repeated with no external load, 90 N anterior draw force, and 5 Nm internal and 5 Nm external rotation torque applied. Results The anterior sMCL lengthened with flexion (p < 0.01) and further lengthened by external rotation (p < 0.001). The posterior sMCL slackened with flexion (p < 0.001), but was lengthened by internal rotation (p < 0.05). External rotation lengthened the anterior dMCL fibres by 10% throughout flexion (p < 0.001). sMCL release allowed the dMCL to become taut with valgus rotation (p < 0.001). The anterior and posterior POL fibres slackened with flexion (p < 0.001), but were elongated by internal rotation (p < 0.001). Conclusion The structures of the medial ligament complex react differently to knee flexion and applied loads. Structures attaching posterior to the medial epicondyle are taut in extension, whereas the anterior sMCL, attaching anterior to the epicondyle, is tensioned during flexion. The anterior dMCL is elongated by external rotation. These data offer the basis for MCL repair and reconstruction techniques regarding graft positioning and tensioning.

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Dynamic Restraints of the Medial Side of the Knee: The Semimembranosus Corner Revisited

The American Journal of Sports Medicine ◽

10.1177/0363546519829384 ◽

2019 ◽

Vol 47 (4) ◽

pp. 863-869 ◽

Cited By ~ 7

Author(s):

Christoph Kittl ◽

Deborah K. Becker ◽

Michael J. Raschke ◽

Marcus Müller ◽

Guido Wierer ◽

...

Keyword(s):

Internal Rotation ◽

Medial Collateral Ligament ◽

External Rotation ◽

Optical Tracking ◽

Anterior Tibial Translation ◽

Collateral Ligament ◽

Posterior Oblique Ligament ◽

Medial Knee ◽

Medial Side ◽

Tibial Translation

Background: Little is known about the dynamic restraints of the semimembranosus muscle (SM). Purpose and Hypothesis: The goal of the present study was to elucidate the role of (1) passive and (2) active restraints to medial-side instability and to analyze (3) the corresponding tightening of the posteromedial structures by loading the SM. It was hypothesized that points 1 to 3 will significantly restrain medial knee instability. This will aid in understanding the synergistic effect of the semimembranosus corner. Study Design: Controlled laboratory study. Methods: Nine knees were tested in a 6 degrees of freedom robotic setup and an optical tracking system. External rotation (ER; 4 N·m), internal rotation (4 N·m), anteromedial rotation (4-N·m ER and 89-N anterior tibial translation), and valgus rotation (8 N·m) were applied at 0°, 30°, 60°, and 90°, with and without an SM load of 75 N. Sequential cutting of the medial collateral ligament and posterior oblique ligament was then performed. At the intact state of the knee and after each cut, the aforementioned simulated laxity tests were performed. Results: The medial collateral ligament was found to be the main passive stabilizer to ER and anteromedial rotation, resulting in 9.3° ± 6.8° ( P < .05), 8.1° ± 3.6° ( P < .05), and 7.6° ± 4.2° ( P < .05) at 30°, 60°, and 90°, respectively. Conversely, after the posterior oblique ligament was cut, internal rotation instability increased significantly at early flexion angles (9.3° ± 3.2° at 0° and 5.2° ± 1.1 at 30°). Loading the SM had an overall effect on restraining ER ( P < .001) and anteromedial rotation ( P < .001). This increased with flexion angle and sectioning of the medial structures and resulted in a pooled 2.8° ± 1.7° (not significant), 5.4° ± 2° ( P < .01), 7.5° ± 2.8° ( P < .001), and 8.3° ± 4.4° ( P < .001) at 0°, 30°, 60°, and 90° when compared with the unloaded state. Conclusion: The SM was found to be a main active restraint to ER and anteromedial rotation, especially at higher flexion angles and in absence of the main passive medial restraints. The calculated tensioning effect was small in all flexion angles for all simulated laxity tests. Clinical Relevance: A complete semimembranosus avulsion may indicate severe medial knee injury, and refixation should be considered in multiligament injury.

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Biomechanical Analysis of an Isolated Fibular (Lateral) Collateral Ligament Reconstruction Using an Autogenous Semitendinosus Graft

The American Journal of Sports Medicine ◽

10.1177/0363546507302217 ◽

2007 ◽

Vol 35 (9) ◽

pp. 1521-1527 ◽

Cited By ~ 74

Author(s):

Benjamin R. Coobs ◽

Robert F. LaPrade ◽

Chad J. Griffith ◽

Bradley J. Nelson

Keyword(s):

Internal Rotation ◽

Knee Flexion ◽

Ligament Reconstruction ◽

External Rotation ◽

Anatomic Reconstruction ◽

Ligament Injury ◽

Collateral Ligament ◽

Fibular Collateral Ligament ◽

Normal Stability ◽

Semitendinosus Graft

Background The fibular collateral ligament is the primary stabilizer to varus instability of the knee. Untreated fibular collateral ligament injuries can lead to residual knee instability and can increase the risk of concurrent cruciate ligament reconstruction graft failures. Anatomic reconstructions of the fibular collateral ligament have not been biomechanically validated. Purpose To describe an anatomic fibular collateral ligament reconstruction using an autogenous semitendinosus graft and to test the hypothesis that using this reconstruction technique to treat an isolated fibular collateral ligament injury will restore the knee to near normal stability. Study Design Controlled laboratory study. Methods Ten nonpaired, fresh-frozen cadaveric knees were biomechanically subjected to a 10 N·m varus moment and 5 N·m external and internal rotation torques at 0°, 15°, 30°, 60°, and 90° of knee flexion. Testing was performed with an intact and sectioned fibular collateral ligament, and also after an anatomic reconstruction of the fibular collateral ligament with an autogenous semitendinosus graft. Motion changes were assessed with a 6 degree of freedom electromagnetic motion analysis system. Results After sectioning, we found significant increases in varus rotation at 0°, 15°, 30°, 60°, and 90°, external rotation at 60° and 90°, and internal rotation at 0°, 15°, 30°, 60°, and 90° of knee flexion. After reconstruction, there were significant decreases in motion in varus rotation at 0°, 15°, 30°, 60°, and 90°, external rotation at 60° and 90°, and internal rotation at 0°, 15°, and 30° of knee flexion. In addition, we observed a full recovery of knee stability in varus rotation at 0°, 60°, and 90°, external rotation at 60° and 90°, and internal rotation at 0° and 30° of knee flexion. Conclusion An anatomic fibular collateral ligament reconstruction restores varus, external, and internal rotation to near normal stability in a knee with an isolated fibular collateral ligament injury. Clinical Significance An anatomic reconstruction of the fibular collateral ligament with an autogenous semitendinosus graft is a viable option to treat nonrepairable acute or chronic fibular collateral ligament tears in patients with varus instability.

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