Anterior interval arthrofibrosis is the condition of abnormal scarring in the 'anterior interval' - the space below the kneecap and behind the patellar tendon.

anterior interval

A normal anterior interval allows free movement of the fat pad, meniscus and patellar tendon.

anterior interval arthrofibrosis

Arthrofibrosis may 'gum' down mobile tissues, including the anterior interval, with adhesions, with consequent reduced range of motion of the knee.


Anterior interval release

To release the scar tissue the surgeon can enter the joint from the suprapatellar area above the kneecap, passing the instrument down under the intermeniscal ligament and into the area behind the patellar tendon.



A very popular and comprehensive coverage of the topic of arthrofibrosis (internal scarring in the knee joint) from Dr Frank Noyes of the Cincinnati Sportsmedicine and Orthopaedic Center.

Dr Peter Millett chats about his experience with infrapatellar contracture syndrome and the importance of recognising it early before the shortening of the patellar tendon becomes irreversible.

Dr Peter Millett discusses why knee surgeons need to be aware that arthrofibrotic scarring can occur in this area because of the position of their arthroscopic portals (cuts).

The editor's interpretation of a 2004 article highlighting the important anatomy associated with arthrofibrosis of the knee.




Anterior interval release in Europe.


Intraarticular arthrofibrosis of the knee alters patellofemoral contact biomechanics. Mikula JD, Slette EL, Dahl KD, Montgomery SR, Dornan GJ, O’Brien L, Turnbull TL and Hackett TR. J Exp Orthop. 2017 Dec; 4: 40.

Fibrosis is a common outcome following total knee arthroplasty Abdul N, Dixon D, Walker A, Horabin J, Smith N, Weir DJ, Brewster NT, Deehan DJ, Mann DA,1 and Borthwick LA. Sci Rep. 2015; 5: 16469.

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eBook - Arthrofibrosis and patella baja

Easy-to-read eBook about a complex topic.