I ran across this dx on numerous occasions and coded as 846.0 which falls under the heading of:
SPRAINS AND STRAINS OF JOINTS AND ADJACENT MUSCLES (840-848)
Includes:
avulsion of joint capsule, legament, muscle, tendon
hemarthrosis of joint capsule, legament, muscle, tendon
laceration of joint capsule, legament, muscle, tendon
rupture of joint capsule, legament, muscle, tendon
sprain of joint capsule, legament, muscle, tendon
strain of joint capsule, legament, muscle, tendon
tear of joint capsule, legament, muscle, tendon
Excludes:
laceration of tendon in open wounds (880-884 and 890-894 with .2)
840 Sprains and strains of shoulder and upper arm
841 Sprains and strains of elbow and forearm
842 Sprains and strains of wrist and hand
843 Sprains and strains of hip and thigh
844 Sprains and strains of knee and leg
845 Sprains and strains of ankle and foot
846 Sprains and strains of sacroiliac region
847 Sprains and strains of other and unspecified parts of back
Tonyj