Medial collateral ligament injury

Last reviewed: 28 Feb 2023
Last updated: 03 Dec 2019



History and exam

Key diagnostic factors

  • injury due to excessive or repetitive valgus loading of MCL
  • medial knee pain
  • joint effusion
  • tenderness
  • laxity on valgus stress testing
More key diagnostic factors

Other diagnostic factors

  • ecchymosis
  • audible pop or tearing sensation at time of injury
  • difficulty walking
  • instability symptoms of knee
  • mechanical knee symptoms
  • knee deformity
  • positive anterior drawer test
  • positive posterior drawer test
  • positive Lachman test
  • positive pivot shift test
  • joint line tenderness
  • chronic pain
Other diagnostic factors

Risk factors

  • participation in activities involving valgus stress at the knee joint
  • age 20 to 35 years
  • age 55 to 70 years
  • weak muscles that cross the medial aspect of knee
More risk factors

Diagnostic investigations

1st investigations to order

  • plain x-rays of knee
  • stress x-rays of knee
More 1st investigations to order

Investigations to consider

  • MRI of knee
More investigations to consider

Emerging tests

  • diagnostic ultrasound

Treatment algorithm


isolated grade I injury

isolated grade II injury

isolated grade III injury

MCL + anterior cruciate ligament (ACL) combined injury

MCL + nonanterior cruciate ligament (ACL) combined injury


persistent high-grade valgus laxity after ≥3 months



Sanjeev Bhatia, MD
Sanjeev Bhatia

Co-Director, Hip & Knee Joint Preservation Center

Northwestern Medicine Central DuPage Hospital

Northwestern University Feinberg School of Medicine




SB receives royalties from the following Nova publication: Ligamentous Injuries of the Knee. SB has stock ownership in Vericel and Joint Preservation Innovations, LLC.

Nikhil N. Verma, MD
Nikhil N. Verma


Department of Orthopedic Surgery

Section of Sports Medicine

Rush University Medical Center




NNV declares the following competing interests: American Orthopaedic Society for Sports Medicine: board or committee member; American Shoulder and Elbow Surgeons: board or committee member; Arthrex, Inc.: research support; Arthroscopy: publishing royalties, financial or material support; Arthroscopy Association of North America: board or committee member; Breg: research support; Cymedica: stock or stock options; Knee: editorial or governing board; Minivasive: paid consultant, stock or stock options; Omeros: stock or stock options; Orthospace: paid consultant; Ossur: research support; SLACK Incorporated: editorial or governing board; Smith & Nephew: IP royalties, research support; Vindico Medical-Orthopedics Hyperguide: publishing royalties, financial or material support; Wright Medical Technology Inc.: research support.

Peer reviewers

Daniel J. Solomon, MD

Co-director of Orthopedic Sports and Shoulder Service

Department of Orthopedic Surgery

Naval Medical Center San Diego

San Diego



DJS declares that he has no competing interests.

Robert Werner, MD


Chief of Physical Medicine and Rehabilitation

Ann Arbor VA Medical Center

Ann Arbor



RW has been reimbursed by the University of Michigan for attending several conferences and has been paid an honorarium for speaking at the American Association of Neuromuscular and Electrodiagnostic Medicine national meeting. RW has been paid by the National Institute for Occupational Safety and Health, the American Dental Association, and SmartHealth as a consultant and has received grant funding from the UAW/GM Health and Safety Board (over US$1 million).

Matthew T. Provencher, MD

Assistant Director

Orthopaedic Shoulder and Sports Surgery

Naval Medical Center San Diego

San Diego



MTP declares that he has no competing interests.

Philip H. Cohen, MD

Clinical Assistant Professor of Medicine

Robert Wood Johnson Medical School

University of Medicine and Dentistry of New Jersey




PHC declares that he has no competing interests.

Jung-Ro Yoon, MD

Orthopedic Surgeon

Department of Orthopedic Surgery

Seoul Veterans Hospital


South Korea


JRY declares that she has no competing interests.

Use of this content is subject to our disclaimer