Bone + Joint Disorders Flashcards
Osteoarthritis, Joint Hypermobility Syndrome, Osteomyelitis, Osteomalacia and Rickett's, Avascular Necrosis, Prosthetic Joint Infection
A 70-year-old man presents to the GP with a 6-month history of pain and stiffness in his left knee. He is a retired gardener and he can cope with his activities of daily living. He is anxious that the pain will worsen to the extent that he will no longer be able to do so. The pain worsens when he kneels and the stiffness lasts less than thirty minutes.
What is the most suitable first-line treatment? - He has osteoarthritis
Topical NSAID
A 76-year-old female sees her GP due to progressively worsening pain in her hands. She is now struggling to do up her buttons when she gets dressed in the morning due to the pain, although she finds that the pain improves after resting for some time. On examination, the GP notes swelling of the distal and proximal interphalangeal joints.
What is the most likely diagnosis?
Osteoarthritis
A 67-year-old woman has struggled with pain and stiffness in her right knee joint for five years and is referred to secondary care for specialist management.
On further questioning, she also reports stiffness, bony swelling and deformity in her fingers bilaterally. She reports that despite perseverance with topical, oral and intra-articular therapy her symptoms have continued to have a significant effect on her quality of life.
A plain radiograph of the knee shows loss of joint space in all three compartments of the joint, with bony spurs seen on the medial side.
What is the single most appropriate next step in this patient’s management?
Joint arthroplasty
A 63-year-old female presents to her GP with a 10-week history of progressively worsening pain bilateral knee pain. The knee pain is worse with activities and can be relieved by rest. She has morning stiffness for around 20 minutes each day. The GP thinks that she may have osteoarthritis.
What is required for a diagnosis of osteoarthritis?
No tests are required as it is a clinical diagnosis
Osteoarthritis can be diagnosed clinically if what?
(1) The patient is aged over 45 years
AND
(2) The patient has activity-related joint pain
AND
(3) The patient has no morning stiffness or the morning stiffness lasts less than 30 minutes
A 39-year-old retired footballer presents with knee pain while walking and climbing the stairs. The pain usually worsens with movements and eases with resting. He had suffered from an Anterior Cruciate Ligament (ACL) injury 10 years ago. Otherwise, there is no trauma to his knees of late. Upon physical examination, there is a limited range of motion, minimal effusion and crepitus felt on both knees.
What is the most likely diagnosis?
Osteoarthritis
Increased bone density beneath the cartilage means what?
It is a characteristic of osteoarthritis, where the degeneration of cartilage leads to increased bone density (subchondral sclerosis) as the bone tries to adapt to the loss of cartilage
Describe the differences between OA and RA
OA
(1) Degenerative, affects large, weight-bearing joints (knees, hips)
(2) Pain worsens with activity, better with rest
(3) Morning stiffness < 30 minutes
(4) Slow progression
(5) No joint disformities
RA
(1) Autoimmune, affects small joints symmetrically (hands, wrists)
(2) Pain, swelling, systemic symptoms (fever, fatigue)
(3) Morning stiffness > 30 minutes
(4) Fast
(5) Joint deformities > swan neck deformity, ulnar deviation etc
What is the first-line treatment for osteoarthritis of the hand or knee?
Paracetamol and topical NSAIDs are first line
Which joints are classically affected in osteoarthritis?
(1) Large weight-bearing joints of the lower limb (hip and knee).
(2) Small joints of the hands, particularly the DIPs (Heberden’s nodes) and PIPs (Bouchard’s nodes
What are the three main aspects of osteoarthritis management?
(1) Conservative (Weight loss, aerobic exercise, and PT / OT input)
(2) Pharmacological (Step up the WHO pain ladder, and steroid injections)
(3) Surgery (joint arthroplasty)
Which signs in the hands are suggestive of osteoarthritis?
Heberden’s and Bouchard’s nodes on the distal and proximal interphalangeal joints respectively
Heberden’s nodes are found in both OA and RA
False.
Only OA
What term describes the flattening or broadening at the base of the thumb often seen in advanced first CMC joint osteoarthritis
Squaring of the thumb
First-line medication for osteoarthritis is what?
Analgesia - paracetamol, topical NSAIDs (avoid opiates) as needed, co-codamol
What defines joint hypermobility syndrome?
A condition where a hypermobile joint develops chronic pain lasting 3 months or longer
In which demographics is joint hypermobility syndrome more common?
Higher incidence in females, presenting usually in childhood or the 3rd decade
Name two rare genetic syndromes associated with joint hypermobility syndrome
(1) Marfan’s syndrome
(2) Ehlers-Danlos syndrome.
What are the common symptoms of joint hypermobility syndrome?
(1) Joint pain after exercise
(2) Stiffness
(3) Frequent sprains/dislocations
(4) foot/ankle pain
What are some physical features that may present with joint hypermobility syndrome?
Thin, stretchy skin; flat feet; and neck pain
What score is used to assess joint hypermobility?
The Modified Beighton Score
What is the threshold score on the Modified Beighton Scale to indicate hypermobility?
A score of 4 out of 9 or higher
Name tests included in the Modified Beighton Score for hypermobility
- Elbow hyperextension >10°
- Thumb touching the forearm with wrist flexion
- Hyperextension of the knees >10°
What is the main management approach for joint hypermobility syndrome?
Physiotherapy
Is surgery recommended for joint hypermobility syndrome?
No
Besides physiotherapy, what other management option is commonly used for pain relief in joint hypermobility syndrome?
Analgesia
What is the difference between hypermobility and joint hypermobility syndrome?
Joint hypermobility by itself can be benign. When this causes pain, this becomes joint hypermobility syndrome.
If a patient presents with joint pain and stiffness, frequent ankle sprains, “double-jointed” (hypermobile) hand and wrist joints, and recurrent shoulder dislocations. What disease does this describe?
Joint hypermobility syndrome
What is osteomyelitis?
Infection of the bone and/or bone marrow
What age group is osteomyelitis more common in?
Children, but it can also occur in adults
What is the main causative organism of osteomyelitis?
Staphylococcus aureus + coagulase-negative staphylococci
Which population is at higher risk for unusual osteomyelitis sites?
People who inject drugs (PWIDs) with infections often in the sternoclavicular, sacroiliac, and pubic joints
Name two key routes of infection for osteomyelitis
Haematogenous (spread via blood) and post-traumatic (direct contact)
What forms as a dead fragment of bone in chronic osteomyelitis?
Sequestrum
What new bone forms around the area of necrosis in osteomyelitis?
Involucrum
What is the first-line investigation for suspected osteomyelitis?
MRI
What is the gold standard test for confirming osteomyelitis?
Bone biopsy
What is the first-line antibiotic treatment for acute osteomyelitis?
Flucloxacillin for Staphylococcus aureus
What is the primary treatment approach for chronic osteomyelitis?
Surgical debridement and IV antibiotics
In which patient group is Salmonella a common cause of osteomyelitis?
Patients with sickle cell anemia
What symptom is common in both acute and chronic osteomyelitis?
Pain at the site of infection
What systemic symptoms can acute osteomyelitis present with?
Fever, malaise, and chills
What is a common orthopaedic complication of recurrent sickle cell crisis?
Avascular necrosis of the femoral or humeral head
Which imaging technique is the best for diagnosing osteomyelitis in patients with diabetic foot ulcers?
MRI scanning
What are the main mechanisms by which infection can spread to the bone, resulting in osteomyelitis?
(1) Seeding from hematogenous infection (commonly occurs in children)
(2) Spread from adjacent soft tissues or joints
(3) Direct inoculation of infection into bone due to wound contamination during trauma or surgery
How is osteomyelitis managed?
Antibiotics for a minimum of 4-6 weeks
(at least 12 weeks, usually 3-6 months, in chronic osteomyelitis)
- Flucloxacillin/rifampicin, vancomycin is MRSA suspected
- If penicillin allergic: give clindamycin
- Start IV and switch to oral antibiotics when patient stable and/or 2 weeks post surgery
Chronic = surgery
What is the treatment of choice for osteomyelitis?
Flucloxacillin for 6 weeks
Penicillin allergy: Clindamycin for 6 weeks
MRSA: Vancomycin or teicoplanin for 6 weeks
In all instances, fusidic acid or rifampicin can be added for the initial 2 weeks
What is the most common pathogen in osteomyelitis of adults?
Staphylococcus aureus
How do patients with osteomyelitis present in acute infections?
Fever, pain, swelling, and erythema of the affected site
How do patients with osteomyelitis present in chronic infections?
(1) A long history of pain
(2) Persistently draining sinus tract or wound
(3) Soft tissue damage
= Risk factors such as diabetes and PVD (peripheral Vascular Disease) also increase the likelihood of this
What is osteomalacia?
Osteomalacia is a defect of bone characterised by abnormal softening due to deficient mineralisation of osteoid, caused by inadequate calcium and phosphorus
What is the pediatric equivalent of osteomalacia?
Rickets
What are the principal causes of osteomalacia and rickets?
The causes include vitamin D deficiency, hypophosphatemia, and impaired calcium absorption or phosphate deficiency
What is the clinical presentation of osteomalacia?
Symptoms
(1) Bone pain (pelvis, spine, femora)
(2) Hypocalcemia symptoms (eg) cramps, irritability)
(3) Easy fractures.
Signs
(1) Proximal myopathy
(2) Dental defects.
What is the clinical presentation of rickets?
Specific signs of rickets include delayed fontanel closure and gen varum (bowing of the legs)
What are the typical lab findings in osteomalacia?
(1) Low calcium
(2) Low serum phosphate
(3) Raised serum alkaline phosphatase (ALP)
(4) Raised PTH
What is the first-line treatment for osteomalacia?
- Vitamin D therapy + Calcium and phosphate supplementation.
- D3 tablets (400-800 IU per day) after a loading dose of 3200 IU per day for 12 weeks are commonly used
How would you manage severe osteomalacia?
A vitamin d level of less than 25 nmol/L reflects deficiency and requires high dose treatment initially followed by maintenance treatment
Vitamin D deficiency leads to inadequate stores of [Blank] and [Blank] in the bone matrix
Calcium and Phosphate
In osteomalacia, bones have a greater proportion of [Blank] bone matrix
Unmineralised
What are the symptoms and signs of rickets?
Bowed legs
Bone pain
Stunted growth
Darker skin tones [Blank] your risk of rickets
Increase
Rickets is a skeletal disorder caused by a prolonged lack of [Blank]
Vitamin D
What is avascular necrosis (AVN)?
Failure of blood supply to a bone’s end, causing ischaemic necrosis
Typical demographic for AVN?
Males, ages 35-50
Most commonly affected bone in AVN?
Femoral head, but can also affect wrist, humerus head
What is the “hanging rope sign” in AVN?
Later MRI sign of femoral head AVN with patchy sclerosis and a lytic zone from granulation tissue
Typical presentation of femoral head AVN?
(1) Insidious groin pain → worsened by stairs or impact; often bilateral
First-line imaging for AVN diagnosis?
MRI
Key management options if AVN is reversible?
Bisphosphonates,
Core decompression
Bone grafting
vascularised fibular graft
What is typically required for irreversible AVN?
Joint replacement (e.g., total hip replacement)
Rotational osteotomy (rare)
Fusion (in wrist/foot)
What is the Steinberg classification used for?
It categorizes stages of AVN, aiding in treatment decisions based on progression
What part of the scaphoid is most prone to avascular necrosis?
The proximal pole
Which region of bone is usually affected by avascular necrosis?
The epiphysis of long bones
What are risk factors for fat necrosis of the breast?
Trauma or surgery
A 65-year-old woman who underwent left knee arthroplasty 2 weeks ago presents complaining of a ‘boring pain’ in the same knee. The pain has gradually worsened over 5 days, and is now affecting her ability to mobilise. She is concerned as the pain is not responding to co-codamol which was prescribed as postoperative analgesia. On examination, she appears feverish and unwell. There is point tenderness and swelling over the left knee. The surgical site is clean, with no visible pus or erythema of note.
A working diagnosis of osteomyelitis is suspected, and an MRI is performed, which shows focal signs of inflammation around the prosthesis and cortical destruction of the proximal tibia. Which is the most appropriate management concerning her antibiotic therapy? - The patient has acute osteomyelitis
IV flucloxacillin
What is Prosthetic Joint Infection?
Periprosthetic infection involving the joint prosthesis and adjacent tissue
Which organisms most commonly cause periprosthetic infections?
Staph. aureus and Staph. epidermidis
Describe the mechanism of periprosthetic joint infection.
Infection can occur from direct inoculation during surgery, joint manipulation, or later through bacteraemia
Differentiate between early, chronic, and haematogenous periprosthetic infections.
Early: Within 2-3 weeks, from surgery;
Chronic: After 3+ weeks
Haematogenous: Abrupt onset, systemically unwell
What causative organisms are found in chronic periprosthetic infections?
S. epidermis
cutibacterium
corynebacterium
S. aureus
What causative organisms are found in haematogenous periprosthetic infections?
S. aureus
GNB
What causative organisms are found in early periprosthetic infections?
Staph. aureus
Coagulase-negative staph (particularly S. epidermis)
What are the common symptoms of periprosthetic infection?
(1) Fever
(2) Joint pain
(3) Minimal swelling
(4) Sometimes sinuses
What does Planktonic bacteria mean?
Is responsible for most symptoms, bacteraemia
What does sessile bacteria mean?
phenotypic transformation of planktonic bacteria to form a biofilm encased in an extracellular matrix
General advice for those with prosthetic Joint Infection
If there is pus, let it out!
What is the primary treatment approach for early or haematogenous infection?
DAIR - Debridement
Antibiotics (for 12 weeks)
Implant retention.
Frail patients with chronic infection - Stage 1 exchange management
- Removal of joint and antibiotics
Chronic infection - Stage 2 exchange management
- Removal of joint and 6 weeks of aggressive antibiotic therapy
- Patient left without a joint for 6 weeks
- Once the infection is under control a revision joint replacement is performed with more complex joint replacement components
What additional antibiotic is recommended for rifampicin-sensitive staph infections?
Rifampicin PO, added to standard antibiotics
What are prophylactic measures taken during joint replacement?
(1) Use of clean-air theatres
(2) 24-hour antibiotics from induction
(3) Antibiotics in cement
(4) Laminar airflow
What is osteomyelitis?
Infection of the bone and bone marrow
Mr Montgomery, a 29-year-old, presents with a fever as well as pain and swelling in the thigh following an open femoral fracture. A diagnosis of osteomyelitis is suspected.
Which imaging modality is needed for a definitive diagnosis?
MRI
What is the treatment for osteomyelitis in a penicillin- allergic patient, and how long should it be given for?
Clindamycin for 6 weeks
68-year-old man attends the GP complaining of worsening pain in his right foot. The pain has been getting worse over the past two days and he now feels generally unwell. He was admitted two weeks ago with an infected arterial ulcer on the base of his right heel and has a history of poorly controlled type 2 diabetes mellitus with a recent HbA1c of 84 mmol/mol. Previously, he was pain-free and had not complained of pain associated with the ulcer.
On examination, there is a deep, circular ulcer on the base of the right heel and he complains of pain on palpation of the foot which is swollen in comparison to the left foot.
What investigation is required for a definitive diagnosis? and why?
Bone biopsy
= The likely diagnosis here is osteomyelitis suggested by the increase in pain, swelling, and fever
Osteomyelitis can present on x-ray with what?
Regional osteopenia
Focal cortical loss
Periosteal changes
Long-term corticosteroid use is a risk factor for what disease?
avascular necrosis
A 60-year-old man describes difficulty in standing from the seated position and diffuse joint and bone pain. Other than a recent fracture sustained from a mechanical fall he has no other past medical history and denies any systemic signs of illness. On examination, he has a waddling gait.
What is the most likely diagnosis?
Osteomalacia
