Knee InjuryCase StudiesA 15-year-old gymnast has noted knee pain that has become progressively worse during the past several months of intensive training for a statewide meet. Her physical examination indicated swelling in and around the left knee. She had some decreased range of motion and a clicking sound on flexion of the knee. The knee was otherwise stable.StudiesResultsRoutine laboratory valuesWithin normal limits (WNL)Long bone (femur, fibula, and tibia) X-rayNo fractureArthrocentesis with synovial fluid analysisAppearanceBloody (normal: clear and straw-colored)Mucin clotGood (normal: good)Fibrin clotSmall (normal: none)White blood cells (WBCs)<200 WBC/mm3 (normal: <200 WBC/mm3)Neutrophils<25% (WNL)Glucose100 mg/dL (normal: within 10 mg/dL of serum glucose level)Magnetic resonance imaging (MRI) of the kneeBlood in the joint space. Tear in the posterior aspect of the medial meniscus. No cruciate or other ligament tearsArthroscopyTear in posterior aspect of medial meniscusDiagnostic AnalysisThe radiographic studies of the long bones eliminated any possibility of fracture. Arthrocentesis indicated a bloody effusion, which was probably a result of trauma. The fibrin clot was further evidence of bleeding within the joint. Arthrography indicated a tear of the medial meniscus of the knee, a common injury for gymnasts. Arthroscopy corroborated that finding. Transarthroscopic medial meniscectomy was performed. Her postoperative course was uneventful.Critical Thinking Questions1. One of the potential complications of arthroscopy is infection. What signs and symptoms of joint infection would you emphasize in your patient teaching?2. Why is glucose evaluated in the synovial fluid analysis?3. What are special tests used to differentiate type of Tendon tears in the knee ? Explain how they are performed (Always on boards)