Trochlear groove

The curved, articulating portions of the trochlea and capitulum are approximately circular in a cross-section. The radius of the capitulum is larger than the central trochlear groove (Table 49.14). The centers of curvature of the trochlea and capitulum lie in a straight line located on a plane that slopes at 45 to 50°... 

Medial trochlear groove radius Distal location of flexion/extension 13.2 1.4... 

Farahmand R, Senavongse W., and Amis A.A. 1998. Quantitative study of the quadriceps muscles and trochlear groove geometry related to instability of the patellofemoral joint. /. Orthop. Res. 16 136. 

Fig. 21.22 (a) Dislocation of the patella to expose the trochlear groove, (b) deepening of the groove trochlear with the aid of gouge forceps, (c) fixing the biosynthesized cellulose membrane with 6-0 synthetic absorbable sutures, (d) suturing the joint capsule and retinaculum in type of points of suture, with 3-0 monofilament nylon thread, and (e) suture the skin with simple stitches apart... 

Milch Type 1 (Fig. 18.11) The fracture line exits lateral to the capitellar trochlear groove and the lateral crista remains intact for the ulna to articulate with. This corresponds to a Salter-Harris type IV physeal injury. 

The patient is supine with the knee extended and relaxed. The examiner pushes the patella caudad in the trochlear groove and then holds it in this position. The patient is instructed to tighten the quadriceps muscle against the examiner s resistance. Palpable crepitation or pain on patellar motion is an indication of roughness of the articulating surfaces, potentially caused by chondromalacia of the patella. 

Fig. 8.2a,h. Elbow joint. Articular anatomy, a Schematic drawing of a midsagittal view through an extended elbow with b CT scan correlation demonstrates the articular relationship between the trochlea of the humerus (H) and the trochlear groove of the ulna (U), leading to flexion and extension joint movements. The extrasynovial anterior (asterisk) and posterior (star) fat pads are closely applied to the distal end of the humerus and lie just superficial to the joint space (in black). Note the insertion of the brachialis (Br) and the triceps (tr) muscles, which are the main flexor and extensor muscles of the elbow respectively... 

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