MSS Case 2: Nerve Injury

Question 1

Identify and trace the course of major nerves and vessels of upper arm

Answer 1

See lecture

Brachial plexus:

1. Musculocutaneous nerve
2. Median nerve
3. Ulnar nerve
4. Radial nerve
5. Axillary nerve

Question 2

List 3 main types of nerve injuries

Answer 2

1. ***Neurapraxia
   - Functional disruption
   - Focal demyelination
2. ***Axonotmesis
   - Microscopic division of nerve axon surrounding myelin sheath
   - No discontinuity
3. ***Neurotmesis
   - Complete division of nerve fibres with discontinuity

Question 3

Basic mechanisms of nerve impulse generation and propagation

Answer 3

See lecture

Question 4

List 2 main sites of body where IM injections are given

Answer 4

1. Gluteal muscle in buttock
   - **upper lateral quadrant to ensure **Sciatic nerve not damaged
2. Deltoid muscle in shoulder
   - avoid ***Radial nerve
   - faster absorption

Benefit of IM injections:

• Larger volume than SC injection
• Faster onset of action
• Applicable for aqueous solution, solutions in oil, suspensions

Question 5

Explain nature and severity of occupational injury in general population

Answer 5

Over 70000 cases of labour injuries every year, over 200 fatal cases

Question 6

Identify role of the Medical Protection Society

Answer 6

1. Aim to help doctors with ethical and medical issues that arise from their clinical practice
2. Indemnity and representation
   - Clinical negligence claim
   - MCHK investigation
   - Disciplinary procedures
   - Preparing for inquests
   - Criminal proceedings
3. Advice
   - Medicolegal advisory service
   - Complaints
   - Handling media attention
   - Counselling and support

Question 7

Define negligence

Answer 7

An Act or Omission that deviates from the reasonable standard of care

Essential elements of medical negligence

1. Established doctor-patient relationship (therefore a duty of care is expected of the doctor)
2. Demonstrates falling below acceptable standards of practice

Test for negligence

1. Bolam test
   - Assess whether the doctor is keeping with the general accepted standards of other doctors
2. Bolitho test
   - Use of “common sense” to say the doctor has failed in his duty

Question 8

DDx of lower back pain

Answer 8

1. ***Mechanical back pain
2. ***Osteomyelitis
3. Osteoporosis
4. ***Osteoarthritis
5. ***Prolapsed IV disc
6. ***Spondylosis
7. ***Traumatic fractures
8. Bone metastasis

Question 9

Red flags signs of back pain

Answer 9

BACK PAIN mnemonic

1. ***Bowel / Bladder dysfunction
2. ***Anaesthesia
3. ***Constitutional symptoms of malignancy
4. Khronic (Chronic) disease
5. ***Paresthesia
6. Age > 50
7. IVDU
8. ***Neuromotor deficits

Question 10

Diagnosis of lower back pain / other MSS disorder

Answer 10

1. Physical examination
   - MSS assessment of spine
   - Specific test e.g. Straight leg test
   - Neurological tests e.g. Myotome, Pinprick test
   - ROM
   - Wasting of muscle
   - Power
   - Reflexes
2. Radiography
   - X-ray
   - MRI
   - Radionuclide bone scan
3. Routine biochemistry and haematology
   - ESR, CRP —> Sepsis / Inflammatory disease
   - Protein + Urinary electrophoresis —> Myeloma
   - PSA level —> Prostate carcinoma / secondary bone metastasis