Knee

• Cartilage in the knee is often torn by young adults or athlete, and the tear occurs when you twist a slightly flexed knee. If the torn cartilage is not treated properly, it can create further damage and cause degenerative arthritis in the knee. There are exercises designed especially for this injury, which can help reduce chronic pain and strengthen the knee.
  
  Straight-leg raises are done while lying on your back. Keeping your knee straight, tighten your thigh muscles, and raise your leg upwards. Lift the leg 12 to 18 inches off the ground, and hold for one second. Lower your legs back down and repeat the process.
  
  Prone flexion is performed while lying on your stomach. Flex your knee, bringing your heel toward your buttocks, and hold before lowering your leg back down.
  
  To perform a seated extension, sit in an upright position. Slowly extend your lower leg until it straightens out. Contract your thigh muscles as tight as possible before lowering.
  
  

Hip

• The cartilage in the hip works as a suction cup to hold your hip joint together. The result of torn cartilage in this area usually stems from degeneration. Exercises can prevent you from breaking your hip or from needing hip replacement surgery.
  
  The best exercises to help repair torn hip cartilage are done through hydrotherapy. Hydrotherapy is physical training that takes place in a pool and is effective because it allows full mobilization without compression through the hip. Using a floating device to run through the water, without touching the bottom of the pool, is an ideal exercise for this injury.
  
  

Shoulder

• The cartilage in the shoulder is located where the ligaments in this area connect to the edge of the socket. When the cartilage is torn, it is because of an injury or trauma suffered in the shoulder. Exercises are designed to treat chronic pain and help you recover your full range of motion.
  
  External rotations are performed while lying on your side. Grasp a light dumbbell with your opposite hand, and keep your elbow bent at a 90-degree angle. Use your elbow as a pivot point on your waist, and rotate your arm upwards until is as vertical as possible.
  
  While in a standing position, hold a light dumbbell in your hand with your palm facing down. Begin the exercise by having the dumbbell at your side, before raising the dumbbell up in front of you. Keep your arm straight, and don't raise the dumbbell any higher then shoulder level.