Massage therapy · Kitchener–WaterlooHyperextended Knee

However, the term hyperextended knee can also refer to people who are hypermobile (have very flexible joints, sometimes described as being double-jointed) (NHS, 2023b) and can naturally hyperextend their knee backwards. A "normal" knee will lock out at a certain angle, usually when the leg is straight, but in someone with hypermobility the knee can extend backwards beyond straight. In cases like this, people will often also have hypermobility in other joints. For example, they may notice that their elbows hyperextend, and their fingers and thumbs are more mobile than normal.

Sometimes this condition is known by a more medical term: genu recurvatum. It is defined as the knee extending backwards by more than 5 degrees beyond straight (Dean et al., 2020). It can be caused by loose (lax) soft tissues around the knee or by injury (Dean et al., 2020).

Tendons connect the muscles to the bones and allow the knee to move. Ligaments join the bones together and keep the knee stable (American Academy of Orthopaedic Surgeons, n.d.).

• The anterior cruciate ligament (ACL) stops the tibia sliding forward on the femur and helps with rotational stability (American Academy of Orthopaedic Surgeons, n.d.).
• The posterior cruciate ligament (PCL) controls backward movement of the tibia on the femur (American Academy of Orthopaedic Surgeons, n.d.).
• The medial collateral ligament (MCL) and lateral collateral ligament (LCL) on either side of the knee control side-to-side movement (American Academy of Orthopaedic Surgeons, n.d.).

A hyperextension injury can damage one or more of these ligaments and other structures at the back of the knee.

1. Protect

Protect the knee by stopping any activity that may cause it to hyperextend. Put as little weight as possible on a painful knee, for example by avoiding standing for long periods (NHS, 2023a).

2. Ice

If you have pain associated with a hyperextended knee, you can try using ice. Use an ice pack or bag of frozen peas wrapped in a tea towel on the knee for up to 20 minutes every 2 to 3 hours (NHS, 2023a).

3. Stabilisation

A knee brace or support may help, and bracing is one of the non-surgical treatments used for genu recurvatum (Dean et al., 2020). I can help you work out which type might suit you and how to get it, and I can supply some basic supports; for a custom brace, I'll point you to the right specialist.

Options outside my scope

• Scans: a doctor may arrange an MRI scan to see whether the ligaments have been damaged (American Academy of Orthopaedic Surgeons, n.d.).
• Surgery: a torn ACL or other badly damaged ligaments may need an operation, which your doctor or surgeon can discuss with you (American Academy of Orthopaedic Surgeons, n.d.).

How I can help (see the My Approach tab)

• Strength, balance and stability work for the knee
• Hands-on work for the muscles around the knee and hip
• Looking at how you walk and land, and getting you back to sport

If your knee locks, gives way, is badly swollen or won't take your weight, see When to get urgent medical advice. After ligament surgery, I need your surgeon's okay before hands-on treatment.