Complex tear of medial meniscus, current injury, unspecified knee

• birth trauma (P10-P15)
• obstetric trauma (O70-O71)

code to identify any retained foreign body, if applicable (Z18.-)

• Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
• The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

• burns and corrosions (T20-T32)
• frostbite (T33-T34)
• injuries of ankle and foot, except fracture of ankle and malleolus (S90-S99)
• insect bite or sting, venomous (T63.4)

• avulsion of joint or ligament of knee
• laceration of cartilage, joint or ligament of knee
• sprain of cartilage, joint or ligament of knee
• traumatic hemarthrosis of joint or ligament of knee
• traumatic rupture of joint or ligament of knee
• traumatic subluxation of joint or ligament of knee
• traumatic tear of joint or ligament of knee

• derangement of patella (M22.0-M22.3)
• injury of patellar ligament (tendon) (S76.1-)
• internal derangement of knee (M23.-)
• old dislocation of knee (M24.36)
• pathological dislocation of knee (M24.36)
• recurrent dislocation of knee (M22.0)
• strain of muscle, fascia and tendon of lower leg (S86.-)

any associated open wound

The appropriate 7th character is to be added to each code from category S83

old bucket-handle tear (M23.2)