Spinal deformities are found in 20% to 80% of patients with OI
Severe disease with nonambulatory status
Scoliosis in OI may progress after skeletal maturity
- may be related to weakened osteoporotic bone
Poor results
Scoliosis 10 to 15 x more common in patients with spastic quadriplegia than spastic diplegia
Typically
- spastic quadriplegic patient
- long C shaped curve
- lumbar apex
- progressive past maturity
- pelvic obliquity / dislocated or subluxed hips
- can extend into cervical spine
- high risk of respiratory compromise
Sitting in wheelchair
Hygiene
Most common reason for litigation against orthopaedic surgeons in THR
Usually from lengthening
1. Nerve palsy
Sciatic nerve - tolerate average 4.4cm lengthening
Common peroneal nerve - tolerate average 2.7 cm lengthening
Lengthen by up to 15-20% of the resting nerve length
- but in reality is unknown and multifactorial
Progressive and chronic disorder associated with cord cavitation & gliosis
Muscle wasting
Dissociate anaesthesia
Scoliosis
Neuropathic arthropathy
M > F
No familial tendency
1. Idiopathic
Lateral curvature of the spine 2° to vertebral anomaly
- causes an imbalance in longitudinal spine growth
True incidence unknown
F > M
Typically Thoracic
No association in twins / suggests not inherited
5% risk in family if complex multi-level
< 4 years by definition
M : F
75% left thoracic
Actually very uncommon
- likely most patients once had spinal dysraphism (Arnold-chiari / syrinx / tethered cord)
- reduced by prenatal folate
Age < 1
- 90 % spontaneously regress
- very important
Disproportionate dwarfism with a short trunk
Problems with dwarfism, spine, vision and hearing
Primary involvement of vertebrae & epiphyseal centres of limbs
Resulting short-trunk dwarfism
- Limb are short, but trunk is even shorter
(cf Metaphyseal Chondrodysplasia - Short limbed Dwarf)
Abnormality of type 1 collagen
- amino acid substitution of glycine with another amino acid
- prevents triple helix formation
Many many deformities described
- some 286 mutations of Type 1 collagen described
There are actually now 7
Type I
- mild
- AD
- blue sclera
Benign, bone-forming neoplasm
- characterized by a small nidus of neoplastic tissue
- surrounded by a wide zone of mature, reactive bone
10% of benign bone tumours
Age 5-25
M:F 2:1
Unknown
- thought may be glomus tumour of bone
Pain secondary to prostaglandin production