Monoarthritis

Clinical application exercises

Methods

• Cases will provide introduction and develop sequentially (history, physical, etc)

• Teams will be prompted to consider management issues during case evolution

• Teams will then find consensus and vote– Discussions between groups will occur to help

decide which, of the supplied options, is the most correct

Case 1

• Jason, a 26-year-old man, presents with a 2-day history of a swollen painful knee. He is concerned it may impact his physical activities. He is employed as a retail clerk in a local sporting store and enjoys competitive skateboarding as a hobby.

Question?

What do you think is the most likely cause of knee pain in this patient?

A.Rheumatoid arthritisB.Septic ArthritisC.Traumatic injuryD.Crystalline arthropathy

• Jason noticed the pain and swelling two days ago, when he woke up. On further questioning, he cannot be sure that the swelling wasn’t there before that. He states the current swelling fluctuates in size during the day.

• He cannot remember any episodes such as an accident or trauma to account for the swelling.

Jason says his friends noticed him limping a bit yesterday, and admits to pain in and around the knee, but not enough to prevent him from skateboarding or going to work.

• The pain fluctuates with activity, worsening after use.

He denies any episodes of ‘locking’ or ‘giving way’.

Jason has otherwise been well medically, and denies having similar symptoms before.

Question?

What other history information would be most useful in helping establish a diagnosis?

A.History of sexual activityB.Associated hip painC.History of smokingD.Past history of knee pain as a teenager

Physical exam - General

• Jason appears healthy and walks into the examination room with a slightly antalgic gait, favouring his left knee.

• Alignment of his limbs shows a slight bilateral genu varum deformity when standing.

• Upper limb, spine and right knee exam is normal to examination.

• Left hip and ankle exam is normal.

Physical exam – Specific (knee)• No specific wasting of the quadriceps muscles noted. • Jason has positive ballottement and milking signs. • Range of motion (ROM) reveals slight decreased

flexion, with discomfort to further flexion past 110 degrees, full extension.

• No crepitus to palpation with ROM. • Perhaps a bit warmer than the contra-lateral knee to

“back of hand” testing. • Collateral ligament testing is stable. • Lauchman’s and posterior drawer signs are normal. • McMurray’s sign is negative.

Question?

What is the significance of positive ballottement and milking signs?

A.Indicative of pre-patellar bursitisB.Indicative of intra-articular fluidC.Indicative of hemarthrosisD.Indicative of periarticular swelling

Question?What would be the most USEFUL next step in

further assessment of this young man at this time? (Consider your differential diagnosis and what can/should be done to confirm or refute your clinical suspicions)

A.Joint aspirationB.MRI with gadoliniumC.Bone scan of entire skeletonD.Uric acid serology

Question?

What testing would you send the joint aspiration fluid for?

A.Culture , C-reactive protein , cell countB.Culture, Crystals, cell countC.C-reactive protein, Gram stain, cell countD.Culture, Gram stain, ESR

Result

• The fluid you obtain is turbid, somewhat watery.

• The analysis reveals 60,000 white blood cells/microliter

• Cultures are pending.

Question?

What would be the most appropriate management for Jason at this time?

A.Knee arthroscopyB.Non steroidal anti-inflammatoriesC.Antibiotic therapyD.Observation

LAB

• Gram stain reveals gram negative diplococci.

Question?

Considering this new information, what would be the most appropriate management for Jason at this time?

A.Knee arthroscopyB.Intra-articular injection steroidsC.Antibiotic therapyD.Intra-articular antibiotics

NOTE

• Gonorrhea (the “clap”) is a reportable disease– Partners need to be contacted

• Testing for Clamydia often done same time and treatment towards both conditions started

CASE 2

Presentation

• While rotating in the Emergency Room, you are asked to evaluate Mr. I. B. Limpin, a 56-year-old here due to his right knee becoming suddenly and progressively painful over the last few hours, prior to his presentation.

History• Symptoms began early that morning,

following his return from a party (Hawaiian theme) during which he consumed 7 or 8 beers, a few martinis, and a number of glasses of champagne. He was told that he passed out while attempting the limbo, falling hard to the floor, and remained obtunded for about 1-2 minutes.

History – Cont’d

• His knee became progressively painful a number of hours after the fall, and currently he cannot bear weight on it despite two tablets of acetaminophen and a hot water bottle applied at home

Question?

How would you classify Mr. Limpin’s articular presentation?

A.Acute polyarticular arthritisB.Acute monoarticular arthritisC.Chronic monoarticular arthritisD.Acute oligoarticular arthritis

Question?

Which one of the following do you consider to be the most likely cause of his knee pain?

A.Pre-patellar bursitisB.crystalline arthritisC.Intra-articular traumaD.osteoarthritis

Past Medical History

• PMH: HTN x 11 yrs, mild chronic renal insufficiency

• Occupation: carpet layer (on his knees for many hours of the day)

• FH: older brother with a history of a periodically painful great toe x 10 yrs– He is not sure what from.

• Social: 1-2 beers nightly, more on weekends; nonsmoker

Question?

Which of the following do you now consider to be the most likely cause of his knee pain?

A.Still Intra-articular traumaB.Crystalline arthritisC.OsteoarthritisD.Bursitis

Examination• BP 159/96mmHg, P 100 – regular, T 36.9C, R 20 –

unlabored, Wt 215 lb, Ht 167 cm • He has a heavy-set habitus with a distended

abdomen. He is holding the involved knee in mild flexion. Cardio/respiratory examination is unremarkable.

• Right knee: diffusely warm, tender across the tibio-femoral joint lines, moderate intra-articular effusion; painful with small arcs of passive motion

Question?

With the information gleaned, which of the following diagnoses can most likely be removed from you differential diagnosis?

A.Intra-articular traumaB.Crystalline arthritisC.OsteoarthritisD.Bursitis

Question?

What would be the most appropriate next step in the management of this patient?

• A. Aspirate the kneeB. Order an x-ray of the kneeC. Order a serum uric acid levelD. Order two sets of blood cultures

Question

• How would you do a knee aspiration?

• Discuss among your team members the issues around this procedure

• Type of equipment (syringe and needle size)• Position of patient and entry portal• How much to remove• What to look for grossly (quality of fluid)• What to send it for

Results

• Your knee aspirate yields 30 cc of opaque, straw-colored fluid that has the viscosity of water. You send it off for a stat WBC count, and routine culture. The gram stain reveals many WBC, but no organisms. Crystal examination reveals negatively birefringment crystals.

Other tests return in 30 minutes:

• WBC (blood): 9.6• WBC count (synovial fluid): 12,400 with 80%

neutrophils• Hemoglobin: 11.8• Creatinine: 2.9• Uric acid: 9.6• Knee film: mild tibiofemoral and patellofemoral

joint space narrowing with marginal osteophytes, no fractures, indirect evidence of joint effusion

Question?

What would be the most appropriate treatment at this time?

A.Colchicine B.Indomethacin C.Probenecid D.Allopurinaol

Evolution

• The synovial fluid culture was negative. He was treated for acute gouty arthritis and his symptoms resolved over a few days. Two weeks later he returns to the clinic (you are now rotating on Medicine, and loving every minute of it), and states he never wants to have another attack of gout ever again.

Question

What would be the most appropriate action to take to accomplish this goal?

A.Start allopurinol aloneB.Start allopurinol and colchicine C.Start colchicine aloneD.Continue only with anti-inflammatories

Case 3

PresentationJoyce is a 70-year-old woman with a one-week

history of pain and swelling of a wrist. She describes a relatively insidious onset of pain over the last 1-2 months in the wrist area. She denies a history of trauma. She complains of occasional morning stiffness in the affected wrist and denies that other joints are problematic to any significant degree. Her past medical history is significant for a previous elbow fracture , diabetes and hypothyroidism.

Question?

Which one of the following do you consider to be the most likely cause of her wrist pain?

A.Intra-articular traumaB.Crystalline arthritisC.Septic arthritisD.Osteoarthritis

Examination

she is a pleasant older woman with normal build. She is afebrile. She has a slightly swollen wrist joint with mild restriction in it’s range of motion. She demonstrates deep palpable tenderness at the radiocarpal joint. Her other joints are essentially normal to examination

Question

Which one of the following is the most likely diagnosis?

A.GoutB.Advanced arthritisC.Osteoporotic fractureD.Pseudogout

Investigations

You perform a joint aspiration of the radiocarpal joint. Synovial fluid shows rhomboid-shaped positively birefringent crystals.

Question?

Which of the following is the best treatment for this patient’s condition?

A.Cast immobilizationB.Vancomycin C.Ibuprofen D.Allopurinol

What we have learned this week

• Approach to patients presenting with acute or chronic monoarticular arthritis

• Issues surrounding septic arthritis and its management

• Workup and treatment of Gout and Pseudo gout

Enjoy your weekend

Polyarthritis RAT Tuesday Morning!