Aquifer Knee Pain

Essay Elements:

• One to three pages of scholarly writing in paragraph format, not counting the title page or reference page
• Brief introduction of the case
• Identification of the main diagnosis with supporting rationale
• Identification of at least two additional differential diagnoses with brief rationale for why these were ruled out
• Diagnostic plan with supporting rationale or references
• A specific treatment plan supported by recent clinical guidelines
• Please refer to the rubric for point value and requirements. In general, these elements must be covered as per the rubric.

Patient Name: Gerta Roman

Ms. Roman is a 74-year-old female who presents with worsening of her chronic right knee pain over the last two weeks. There is no history of trauma, no constitutional symptoms, and no morning stiffness. Physical exam reveals mildly decreased range of motion of the right knee with crepitus and a small effusion and warmth but no erythema and no skin lesions are present.

The ideal summary statement concisely highlights the most pertinent features without omitting any significant points. The summary statement above includes:

1. Epidemiology and risk factors: 74-year-old female with chronic right knee pain
2. Key clinical findings about the present illness using qualifying adjectives and descriptive language:

• No history of trauma
• No constitutional symptoms
• No morning stiffness
• Decreased range of motion
• Crepitus
• Small effusion
• No erythema
• No skin lesions
• Past medical history:
  • History of GERD
  • Remote history of alcohol use disorder
  • Past surgical history:
  • Tonsillectomy as a child and no other surgeries
  • Medications:
  • Multivitamin
  • Extra-strength Tylenol
  • Tums as needed for heartburn
  • No herbal supplements.
  • Review of systems: Normal, except for the right knee pain, occasional left knee pain, intermittent back pain, and occasional heartburn. She reports no fevers, weakness, numbness, or tingling.Family history: Her mother has type 2 diabetes and osteoarthritis, and her dad has “skin problems.”Social history: Doesn’t drink alcohol or smoke. She is a retired teacher and lives alone in a two-story home in a rural community. Her hobbies include gardening and playing with her granddaughter, Lucy, who lives nearby.Since Ms. Roman hasn’t had a drink in years, you decide to skip screening her for alcohol disorders.
• Vital signs:
  • Temperature is 37.1 °C (98.8 °F)
  • Pulse is 64 beats/minute
  • Respiratory rate is 18 breaths/minute
  • Blood pressure is 130/80 mmHg
  • No conjunctivitis or apparent skin lesions.The patient favors putting weight on her left knee a little, but she does not have much trouble climbing onto the table.No erythema, edema, bruising, or atrophy of the quadriceps on either leg. Some tenderness to palpation along both the medial and lateral joint lines on the right leg.Range of motion is 120 degrees in her right leg. Some crepitus with motion in the right patella. Small effusion appreciated from milking the right suprapatellar pouch. Right knee joint is slightly warm compared to the left. No fullness in the popliteal fossa.Negative Lachman and McMurray tests. No pain or laxity with varus or valgus stress. Negative anterior and posterior drawer tests.Hip exam is unremarkable, with no tenderness and a normal range of motion.Ankle exam is unremarkable, with no tenderness and normal range of motion.
• In Ms. Roman’s case, a knee sprain (C), osteoarthritis (E) and rheumatoid arthritis (G) are the most likely causes of her subacute to chronic knee pain. Knee sprains are very common. Though they are typically associated with a history of trauma, the trauma may be minor enough that a patient may not recall it. Osteoarthritis is the most likely cause of her pain. Rheumatoid arthritis is slightly less common than OA but still can cause pain with a mild effusion (as she has). Her mention of wrist pain could also indicate that she has more joints involved, which would be consistent with RA.Suspected infectious process causing knee pain
• If concerned about septic arthritis or an acute inflammatory arthropathy, check a complete blood count (CBC) with differential and erythrocyte sedimentation rate (ESR) or C-reactive protein, though these tests are nonspecific.Perform an arthrocentesis and send the fluid for cell count with differential, glucose and protein, bacterial culture and sensitivity, and polarized light microscopy for crystals. An arthrocentesis can also help differentiate between simple effusion and hemarthrosis or occult osteochondral fracture. A delay in diagnosis of septic arthritis can lead to serious joint damage, so an arthrocentesis must be performed immediately if this diagnosis is under consideration.
  • A simple joint effusion produces clear, straw-colored transudative fluid. This can happen with osteoarthritis and degenerative meniscal injuries.
  • Hemarthrosis is typically caused by a tear of the anterior cruciate ligament or a fracture. A bloody knee aspirate can be associated with a knee sprain (i.e., ACL, PCL) or acute meniscal tear. An osteochondral fracture causes hemarthrosis with fat globules.
  • Suspected rheumatoid arthritis causing knee painIf considering RA, check rheumatoid factor (RF) on blood work. While not very sensitive, this test has a high likelihood ratio for a positive test with a positive predictive value of 95%. Hand x-rays may also identify erosions and soft tissue swelling, which, if found, indicate a high likelihood of RA.Trauma causing knee painTo evaluate knee pain following trauma, apply the Ottawa Knee Rules to decide whether or not to order an x-ray.