Orthopaedic Jobs

Medial Compartment of the Knee



- See: Medial Collateral Ligament:

- Superficial Layer (Layer I)
    - most superficial layer includes the deep fascia that arises from anterior to posterior encases entire medial aspect of 
           the knee & coalesces w/ hamstring muscles and posteromedial capsule;
           - this first layer is superficial to superficial MCL;
    - includes investing fascia of sartorius, fascia overlying gastroc & popliteal fossa;
           - anteriorly layer I blends w/ medial retinaculum as it inserts into proximal aspect of the tibial palteau;
    - superficial fascia layer of medial retinaculum of knee joints posteromedially with layer of the pes arserinus tendons 
           (including semitendinosus) and continues posteriorly as a common sheath in popliteal fossa;

- Middle Layer (Layer II)
    - includes superficial MCL which has very distal insertion on medial aspect of tibia at level of pes anserinus;
           - considered the primary static stabilizer to valgus stress;
    - there may be both parallel & oblique portions of this MCL, which inserts almost 8 cm below joint line & is post to pes anserinus;
    - most posterior portion of layer II, from posterior oblique ligament, has direct fibers that run from medial epicondyle, blending w/layer III &
            attaching to posterior tibial articular surface;
           - these fibers are also augmented by contricutions from fascia overlying semimembranous;
           - anteriorly, layer II splits vertically, w/ one portion merging w/ medial retinaculum & other w/ patellofemoral ligament;

- Deep Layer:
     - deep MCL (deepest layer of medial structures)
     - its posterior extension, posteromedial capsule, includes posterior oblique ligament, described by Hughston;
     - true capsule of joint is most intimate connection w/ synovium;
     - it is very thin anteriorly, but at level of joint, deep to superficial MCL, is thickening of layer III identified as deep MCL;
     - anteriorly, there is bursa interposed between these 2 ligaments, whereas posteriorly they merge w/ ea other & meniscotibial lig;
     - deep MCL is a major secondary restraint to anterior translation



The supporting structures and layers on the medial side of the knee: an anatomical analysis.

The Anatomy of the Medial Part of the Knee



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, April 30, 2012 4:59 pm