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. 2024 Jul;52(8):1952-1959.
doi: 10.1177/03635465241251454. Epub 2024 May 20.

Effect of a Partial Superficial and Deep Medial Collateral Ligament Injury on Knee Joint Laxity

Wouter Beel  1 , Callahan Doughty  2 , Thiago Vivacqua  1 , Alan Getgood  1   3 , Ryan Willing  3   4
Affiliations

Effect of a Partial Superficial and Deep Medial Collateral Ligament Injury on Knee Joint Laxity

Wouter Beel et al. Am J Sports Med. 2024 Jul.

Abstract

Background: Injuries to the medial collateral ligament (MCL), specifically the deep MCL (dMCL) and superficial MCL (sMCL), are both reported to be factors in anteromedial rotatory instability (AMRI); however, a partial sMCL (psMCL) injury is often present, the effect of which on AMRI is unknown.

Purpose: To investigate the effect of a dMCL injury with or without a psMCL injury on knee joint laxity.

Study design: Controlled laboratory study.

Methods: Sixteen fresh-frozen human cadaveric knees were tested using a 6 degrees of freedom robotic simulator. The anterior cruciate ligament (ACL) was cut first and last in protocols 1 and 2, respectively. The dMCL was cut completely, followed by an intermediary psMCL injury state before the sMCL was completely sectioned. Tibiofemoral kinematics were measured at 0°, 30°, 60°, and 90° of knee flexion for the following measurements: 8 N·m of valgus rotation (VR), 4 N·m of external tibial rotation, 4 N·m of internal tibial rotation, and combined 89 N of anterior tibial translation and 4 N·m of external tibial rotation for both anteromedial rotation (AMR) and anteromedial translation. The differences between subsequent states, as well as differences with respect to the intact state, were analyzed.

Results: In an ACL-intact or -deficient joint, a combined dMCL and psMCL injury increased external tibial rotation and VR compared with the intact state at all angles. A significant increase in AMR was seen in the ACL-intact knee after this combined injury. Cutting the dMCL alone showed lower mean increases in AMR compared with the psMCL injury, which were significant only when the ACL was intact in knee flexion. Moreover, cutting the dMCL had no effect on VR. The ACL was the most important structure in controlling anteromedial translation, followed by the psMCL or dMCL depending on the knee flexion angle.

Conclusion: A dMCL injury alone may produce a small increase in AMRI but not in VR. A combined dMCL and psMCL injury caused an increase in AMRI and VR.

Clinical relevance: In clinical practice, if an increase in AMRI at 30° and 90° of knee flexion is seen together with some increase in VR, a combined dMCL and psMCL injury should be suspected.

Keywords: ACL reconstruction failure; anterior cruciate ligament; anteromedial rotatory instability; biomechanics; instability; medial collateral ligament.

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Conflict of interest statement

One or more of the authors has declared the following potential conflict of interest or source of funding: Support was provided by Smith & Nephew, in the form of a research grant that funded the presented research; Ossur, in the form of an educational grant for our research fellowship position; the Natural Sciences and Engineering Research Council (NSERC) Discovery: RGPIN-2018-05693; the Ontario Early Researcher Award ER18-14-197; and the Canadian Foundation for Innovation JELF and Ontario Research Fund–Research Infrastructure, 38141. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Figures

Figure 1.
Figure 1.
The 2 cutting protocols (n = 8 samples for each protocol). ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
Figure 2.
Figure 2.
Anteromedial rotation (AMR) for each flexion angle in all knee states for protocols 1 and 2. Results are given in degrees as mean ± SD. *Statistically significant differences compared with the previous states as well as with the intact state. ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
Figure 3.
Figure 3.
Anteromedial translation (AMT) for each flexion angle in all knee states for protocols 1 and 2. Results are given in millimeters as mean ± SD. *Statistically significant differences compared with the previous states as well as the intact state. ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
Figure 4.
Figure 4.
External rotation (ER) for each flexion angle in all knee states for protocols 1 and 2. Results are given in degrees as mean ± SD. *Statistically significant differences compared with the previous states as well as the intact state. ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
Figure 5.
Figure 5.
Internal rotation (IR) for each flexion angle in all knee states for protocols 1 and 2. Results are given in degrees as mean ± SD. *Statistically significant differences compared with the previous states as well as the intact state. ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
Figure 6.
Figure 6.
Valgus rotation (VR) for each flexion angle in all knee states for protocols 1 and 2. Results are given in degrees as mean ± SD. *Statistically significant differences compared with the previous states as well as the intact state. ACL, anterior cruciate ligament; dMCL, deep medial collateral ligament; psMCL, partial superficial medial collateral ligament; sMCL, superficial medial collateral ligament.
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References

    1. Ahn JH, Lee SH. Risk factors for knee instability after anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2016;24(9):2936-2942. - PubMed
    1. Ball S, Stephen JM, El-Daou H, Williams A, Amis AA. The medial ligaments and the ACL restrain anteromedial laxity of the knee. Knee Surg Sports Traumatol Arthrosc. 2020;28(12):3700-3708. - PMC - PubMed
    1. Battaglia MJ, Lenhoff MW, Ehteshami JR, et al.. Medial collateral ligament injuries and subsequent load on the anterior cruciate ligament: a biomechanical evaluation in a cadaveric model. Am J Sports Med. 2009;37(2):305-311. - PubMed
    1. Griffith CJ, LaPrade RF, Johansen S, Armitage B, Wijdicks C, Engebretsen L. Medial knee injury, part 1: static function of the individual components of the main medial knee structures. Am J Sports Med. 2009;37(9):1762-1770. - PubMed
    1. Grood ES, Noyes FR, Butler DL, Suntay WJ. Ligamentous and capsular restraints preventing straight medial and lateral laxity in intact human cadaver knees. J Bone Joint Surg Am. 1981;63(8):1257-1269. - PubMed

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