Orthopaedics - Hip and Spine Flashcards
Define Osteoarthritis
Degenerative joint disease characterised by a loss of articular cartilage, with associated periarticular bone response
What are the findings on an X ray that indicate osteoarthritis?
- Narrowing of joint space
- Osteophyte formation
- Subchondral sclerosis
- Cysts
Which joints are most commonly affected by osteoarthritis?
Knee
Hip
What are the systemic risk factors for hip OA?
> 45yrs
Women > Men
Genetic link
Vitamin D deficiency
What are the local risk factors for hip OA?
Obesity History of trauma to hip Anatomic abnormality Myopathy Joint laxity Participation in high impact sports
What is the usual presenting complaint of a patient with hip OA?
- Dull aching pain around the hip - can extend up to the knee
- Pain is aggravated by activity and relieved by rest
- Joint may feel stiff after a period of immobility
What examination findings may be found on a patient with hip OA?
- Muscle wasting of quads and glutes
- Reduced power of the hip joint
- Leg length discrepancy
- Fixed flexion deformity
- Antalgic or Trendelenberg gait
- Crepitus
- Reduced range of movement
What are the main DDx of hip OA?
- Trochanteric bursitis
- Gluteus medius tendinopathy
- Sciatica
- AVN of femoral head
- # NOF
What system can be used to classify OA progression?
The Western Ontario and McMaster Universities Arthritis Index (WOMAC) Combines: - 5 items for pain (0-20) - 2 for stiffness (0-8) - 17 for function (0-68) To give a total out of 96
What initial management is given for hip OA?
Analgesia
Lifestyle modification
Physiotherapy
What surgical intervention can be indicated in hip OA?
Hip replacement – total vs hemi arthroplasty
What common post operative complications are there of a hip replacement?
Thromboembolic disease Bleeding Dislocation Infection Losening of prosthesis Leg length discrepancy
How long on average are modern hip protheses designed to last for?
15-20 years
Which approach for hip replacement surgery has the highest risk of sciatic nerve damage?
Posterior approach
Which approach gives full exposure of the acetabulum in hip replacement surgery?
Anterolateral approach
Which approaches preserve the abductor mechanism in hip replacement surgery?
Posterior and anterior approach - allows for fast rehabilitation
Which approach has the lowest dislocation rate in hip replacement surgery?
Anterior approach
What is the one year mortality for a #NOF?
30%
Describe the blood supply to the femoral head
The majority arrives from the medial femoral circumflex artery (arising from the deep femoral artery)
The blood supply is primarily uni-directional
During early life what additional supply is there to the femoral head?
Ligamentum arteriosum (within the ligamentum teres)
What classification system is used to differentiate intracapsular #NOF types? Briefly describe it?
Garden Classification I = Non displaced + incomplete II = Complete but non displaced III = Complete with partial displacement IV = Complete and fully displaced
How can a #NOF be classified based on the fracture line?
Intracapsular – Subcapital or basovervical
Extracapsular – Intertrochanteric or subtrochanteric
What will a #NOF generally look like on examination? Why is this?
Leg is characteristically shortened and externally rotated - pull of short external rotators
What movements will be limited in a patient with a #NOF?
Patient unable to straight leg raise
Pain on pin rolling the leg
Pain on axial loading
What may be a cause of a #NOF to exclude if there is no history of trauma?
Pathological fracture
Which types of #NOF are best managed by a dynamic hip screw?
Intertrochanteric
Basocervical
What is the main surgical option for a subcapital #NOF?
Hemiarthroplasty
When is a cannulated hip screw indicated?
Non-displaced + intracapsular #NOF
What surgical option may be used for a subtrochanteric #NOF?
Intramedullary femoral nail
What are the possible immediate postoperative complications of hip surgery?
Pain
Bleeding
Leg length discrepancy
Potential NV damage
What long term complications are there following surgical repair of a #NOF?
Joint dislocation
Aseptic loosening
Peri-prosthetic fracture
At what age is the peak onset of cauda equina syndrome?
40-50yrs
Where does the cauda equina begin?
L1
What are the most common causes of cauda equina?
- Disc herniation
- Trauma
- Neoplasm
- Infection
- Chronic spinal inflammation
- Iatrogenic (eg. haematoma due to anaesthesia)
What are the red flag symptoms for cauda equina?
- Bilateral sciatica
- Severe or progressive bilateral neurological deficit in the legs
- Urinary or faecal incontinence
- Saddle anaesthesia
- Lack of anal tone
What should be done as part of the examination in cauda equina syndrome?
DRE
Post-void bladder scan
How can cauda equina be classified?
- Cauda equina syndrome with retention
- Incomplete cauda equina syndrome
- Suspected cauda equina syndrome
What are the DDx for cauda equina syndrome?
- Radiculopathy
- Cord compression
What is the gold standard investigation for cauda equina?
Whole spine MRI
What is the management for cauda equina syndrome?
- Early neurosurgical review
- High dose steroids eg. dexamethasone
- Surgical decompression
- Radiotherapy +/- chemo if malignancy is underlying cause
Define a radiculopathy
Conduction block in the axons of a spinal nerve or its roots, causing an impact on motor axons (leading to weakness) and sensory axons (causing paraesthesia)
Distinguish radiculopathy from radicular pain
Radiculopathy - state of neurological loss
Radicular pain - pain servicing from damage/irritation of spinal nerve tissue (particularly the dorsal root ganglion)
What are common causes of nerve compression?
- Intervertebral disc prolapse
- Degenerative diseases of the spine
- Fracture
- Malignancy
- Infection
What are pseudoradicular pain syndromes?
Conditions that do not arise directly from nerve root dysfunction, but cause radiating limb pain in an approximate radicular pattern
What are the main differential diagnoses for radicular pain?
- Referred pain
- Myofascial pain
- Thoracic outlet syndrome
- Greater trochanteric bursitis
- Iliotibial band syndrome
- Meralgia paraesthetica
- Piriformis syndrome
What symptomatic management can be given for radicular pain?
- WHO analgesic ladder
- Neuropathic pain meds (eg. Amitriptyline + gabapentin)
- Benzodiazepines +/- baclofen (for muscle spasms)
- Physiotherapy
What are the main causes of acute spinal cord compression?
- Metastatic
- Fracture
- Facet joint dislocation
- Infective (abscess formation)
- Disc prolapse
- Inflammatory conditions eg. RA, Ank spons
- Degenerative disease (eg. ligament flavum hypertrophy)
What are the main clinical features of spinal cord compression?
- Impaired sensation and proprioception at dermatomal levels below
- Pain (often aggravated by straining)
- UMN signs
- Autonomic dysfunction (late stage)
What are the main upper motor neurone lesion signs?
- Hypertonia
- Hyperreflexia (initial flaccidity)
- Babinski’s sign
- Clonus
What are the main DDx to consider for spinal cord compression?
- Lumbago (lower lumbar pain)
- Sciatica (lower back pain)
- Cauda equina syndrome
What is the gold standard investigation for suspected spinal cord compression? Within what timescale should this be done?
MRI of the spine
- Within a week if spinal mets suggested
- Within a day if compression
What is the management for spinal cord compression?
- High dose corticosteroids –> improve functional prognosis + PPI (for gastric protection)
- Immediate referral to neurosurgery + oncology opinion
What is the definitive management for metastatic spinal cord compression?
Decompression
What indicator can be used for prognosis of metastatic spinal cord compression?
Mobility state at time of treatment
What is the average survival time for metastatic spinal cord compression?
6 months after onset (due to often being an advanced stage of disease)
