Chondrolysis
Definition
- loss of 50% joint space or < 3mm joint space
Epidemiology
- female 2:1
- 10-20% of SUFE
Causes
1. Head penetration
- use only 1 screw
2. Immunologically mediated global loss of articular cartilage
- can occur in no treatment of SUFE
Clinical
- painful and reduced ROM
- flexion / adduction contracture
Management
- rest / ROM exercises / NSAID
- ilizarov distraction - unknown long term results
- 50% resolve
- very difficult problem - may need THR / arthrodesis
AVN
Incidence
- 5 % in chronic slips
- 20% in acute on chronic slip
- up to 50% in unstable slip
- much worse if MUA
Risk factors
1. Reduction
2. Posterosuperior quadrant pin placement
3. > 1 pin
4. Severity slip
- ? results skewed by increased MUA in this group
5. Unstable SUFE - unable to weight bear / Loder
Salvage options
1. Hip distractor
2. Valgus osteotomy
- redirect WB area away from AVN
Subtrochanteric Fracture
Cause
- too low screw entry
- multiple drill holes to get correct entry
Management
- > 15 reconstruction nail
- < 15 DHS or DCS
Further physeal slipping
Cause
- poor screw positioning
- young patient
- failure physeal fusion
- removal of screw before fusion
Cam FAI
Principle
Epiphysis heals in a posterior and inferior position = abnormal contact of relatively anterior neck on the acetabulum
Incidence
- common with moderate - severe nonrealigned
Options
1) Joint Preserving
- Arthroscopic - Osteochondroplasty
- Open - Osteochondroplasty with open surgical dislocation +/- Dunn Osteotomy at the level of the femoral neck
2) Joint Sacrificing - THR for advanced cases
OA
Natural History
Not completely known
- still occurs in uncomplicated treatment SUFE
- even unknown if pistol grip deformity is from SUFE
Schlenzka et al, Bone Joint J. 2023
- retrospective review of 172 hips post insitu fixation
- 41% of hips end in THA at 50 year follow up
- 155 hips with 40 year follow up
- 24% THA
Wensaas et al J Child Orthop 2011
- 76 hips with 38 year follow up
- 21% THA