Ch89 Differential Spine - signs and symptoms Flashcards
(28 cards)
What are the causes of myelopathy?
Trauma Degenerative (disc disease / OPLL) Tumour - MSCC / paraneoplastic / leptomeningeal Vascular - haematoma / AVM / infarct Demyelinating - Transverse myelitis / MS / NMO (more than 3 levels) Metabolic - Vit B12 deficiency (associated with pernicious anaemia) Amyotrophic lateral sclerosis / primary lateral sclerosis
How do you test for Pernicious anaemia?
Schilling test - give radiolabelled Vit B12 without intrinsic factor and then with intrinsic factor and measure the amount of the radiolabelled Vit B12 in the urine
Where does the piriformis muscle attach?
From the VB of S2-3, through the greater sciatic notch to the greater trochanter
What is the root innervation to piriformis and what is its function?
L5/S1 and causes hip ext rotation
What is piriformis syndrome?
Where the piriformis muscle causes compression of the sciatic nerve
Test using the PACE test which is where resisted external rotation of the hip reproduces symptoms
How do you distinguish L4 radiculopathy from femoral nerve neuropathy?
Femoral neuropathy causes anterior thigh numbness, weak hip flexion (due to iliopsoas) and normal adductors.
L4 radiculopathy causes numbness of the medial leg (spares the thigh which is L3), has normal hip flexion power and weak adductors.
Note: both will have weak knee extension
What cells do motor fibres in the precentral gyrus arise from?
Pyramidal cells of Betz
What does an internal capsule lesion cause?
Pure motor hemiparesis without sensory impairment. Most commonly due to lacunar infarcts.
What is suggested by nocturnal back pain relieved by aspirin?
Osteoid osteoma / osteoblastoma
What is Patrick’s test for ankylosing spondylitis?
Compressing the pelvis in the lateral decubitus position causing pain suggests ankylosing spondylitis (sacroiliitis)
What is Reiter syndrome?
A reactive arthritis following a bacterial infection in patients that are HLA-B27 positive. Has non-joint involvment also e.g. skin lesions, uveitis etc.
What is a Schmorl’s node?
Herniation of disc through the endplate into the vertebral body
What is the nerve supply to tibialis anterior?
Deep peroneal nerve (L4/5)
How do you differentiate L5 radiculopathy and common peroneal nerve palsy as causes of foot drop?
Tibialis posterior (tibial nerve) and gluteus medius (superior gluteal nerve from the sacral plexus) are spared with common peroneal nerve injury but not L5 radiculopathy. This means that foot inversions and hip abduction are normal. Test hip abduction (gluteus medius function) with Trendelenburg sign when getting them to walk.
How do you differentiate deep, supfl and common peroneal nerve injuries?
Deep peroneal nerve injury causes a pure motor foot drop with loss of ankle eversion.
Supfl peroneal nerve injury causes a numb lateral leg but no foot drop.
Common peroneal nerve injury causes both weakness and numbness.
What weakness pattern is seen with peripheral neuropathies?
Distal > proximal causing wrist and ankle drop
What muscle do you check for L2/3 root function?
Hip adductors. Supplied by the obturator nerve (L2,3,4).
What muscle do you check for L4 root function
Quadriceps femoris (L4) innervated by the femoral nerve
How do you localise a sciatic nerve lesion?
Root lesion - paraspinal muscle weakness
Lumbar plexus - weakness of gluteus medius (hip abduction) and maximus (hip extension) but sparing of paraspinal muscles
Sciatic nerve (prox to common peroneal nerve branch) - biceps femoris (flexion of the knee) and gastrocnemius (plantar flexion) are weak
Tibial nerve (weakness of tibialis posterior so cannot invert the foot).
Deep peroneal nerve causes foot drop through weakness of tibialis anterior
Supfl peroneal nerve (weakness of ankle eversion but no foot drop)
Which muscles do the superior and inferior gluteal nerves innervate?
Superior innervates the gluteus medius, minimus and tensor fasciae lata
The inferior gluteal nerve innervates gluteus maximus
What are the causes of hand atrophy/weakness?
Cervical myelopathy / radiulopathy
ALS
Central cord syndrome
Syrinx
Brachial plexus injury
Brachial plexus inflammation = parsonage turner syndrome
Peripheral nerve impingement (median / ulnar)
Thoracic outlet syndrome
What is Bell’s cruciate paralysis?
Where a foramen magnum lesion causes upper limb but not lower limb weakness due to compression of the medulla at the site of the UL decussation but sparing the more laterally located LL fibres that decussate lower.
What causes atrophy of the first dorsal interosseous?
C8/T1 radiculopathy
Lower brachial plexus involvement (pancoast / thoracic outlet syndrome)
Ulnar neuropathy (elbow or Guyon’s canal)
ALS / mutlifocal motor neuropathy
What is Adson test for thoracic outlet syndrome?
Turn head to ipsilateral side
Feel pulse
Raise ipsilateral arm
Feel if pulse dimishes.
*Reverse Adson test if you turn head to the other side
