Slipped capital femoral epiphysis- SUFE Flashcards
1
Q
What is SUFE?
A
- Disorder of the PROXIMAL FEMORAL EPIPHYSIS -> SLIPPAGE OF EPIPHYSIS RELATIVE TO THE FEMORAL NECK
2
Q
What slips?
A
- The EPIPHYSIS STAYS IN THE ACETABULUM while the NECK DISPLACES ANTERIORLY & EXTERNALLY ROTATES
- the epiphysis is posterior
3
Q
What is the pathology of SUFE?
A
- Due to mechanical forces acting on a susceptible physis
4
Q
Where does slippage occur? Why here?
A
- thru HYPERTROPHIC ZONE of the PHYSIS
- Caused by Weakness in the PERICHONDRAL RING
- Cartilage in the hypertrophic zone acts as a weak spot
- In renal dystrophy-SUFE occurs in secondary spongiosa
5
Q
What is the epidemiology?
A
- Most common disorder affecting adolescent hips
- more common in
- males (av age 13,4 boys, in girls 12.2)
- africa americans/pacific islanders
-
obese children
- **single greatest risk factor
- during period of rapid growth- puberty
- Left hip more common than right
- BILATERAL IN 17-50%
6
Q
What are the associated factors?
A
- Reduced Femoral anteversion, reduced femoral neck shaft angle
- Obesity
-
Endocrine disorders
- if child <10 yrs, weight <50th percentile
- hypothyroidism- 40%
- osteodystrophy of chronic renal failure
- growth hormone tx
7
Q
Can you describe a classification for SUFE?
A
-
Stable vs unstable Stable
- Stable = able to weight bear with or without crutches. Minimal risk of AVN- 105
-
Unstable= Unable to WB w/wout crutches
- Assoc w high risk AVN= 47%
- Provides prognostic information
8
Q
Who classification system is this? Why is it important?
A
- LODER
- it predicts the risk of osteonecrosis- give PROGNOSIS i.e stable <10% of ON Unstable 47% risk of ON
9
Q
What other classification systems do you know?
A
-
TEMPORAL - rarely used
- Acute= symptoms 3 weeks
- acute on chronic= acute exacerbation of long standing symptoms
- Chronic= Symptoms Persist > 3 weeks
10
Q
Can you describe a grading system to the slippage?
A
- Southwick angle
- identifies the degree of slippage
- by subtracting the epiphyseal-shaft angle on the uninvolved side from that on the side with SCFE on the frog leg lateral pelvis radiograph.
- Mild= <30% of slippage
- Moderate = 30-50% of slippage
- Sevre =>50% of slippage
11
Q
What do pt present with?
A
- Symptoms are usually Present for weeks- months before dx
- Groin/ thigh painmost common
- frequently pc KNEE pain (15-23%)
- pt sits with affected led crossed over other!
12
Q
What would you find on examination?
A
- Coxalgic- ** external rotated gait or trendelenberg gait**
- OBLIGATORY EXT ROTATION during passive FLEXION OF HIP
- LOSS of INTERNAL Rotation, ABDUCTION, FLEXION
- LLD- shorter leg
- Externally rotated foot progression angle
- Thigh atrophy
13
Q
What imaging would you request?
A
-
Ap and frog lateral bilateral hips
- FL is best to identify slippage
- AP - draw KLEIN’s line
- line superior border of femoral neck -will not intersect femoral head in a child with SUFE ( will in normal hip)
- EPIPHYSIOLYSIS- growth plate widening or lucency- early sign
- Blurring of prox femoral metaphysis - Blanch sign of Steel
- MRI- can help to diagnose a PRESLIP condition when radiographs are negative
- shows growth plate widening and increased signal of metaphysis
14
Q
What tx would you give in unstable and stable slips?
A
- Operative PERCUTANEOUS INSITU FIXATION
15
Q
What is the goal of percutaneous screw fixation?
A
- Stabilise the epiphysis
- prevent further slippage and promote closure of the proximal femoral epiphysis
20
Q
Can you describe any other surgical options?
A
1)Controlled open reduction and capital realignement- controversial , maybe for unstable , high grade sufe
- sugical dislocation with epiphyseal reorientation
- modified Dunn proceedure with formation of a epiphyseal vascular flap
2) Proximal Femoral Osteotomy
- for correction of pain or function
- can be preformed at subcapital, femoral neck, intertrochanteric & subtrochanteric regions
- subcapital /femoral neck osteotomies provide the most correction but associated with the highest risk of AVN and should be avoided
- Typical ostetomy produce flexion, valgus and derotation- imhauser
- correction is obtained via an anterior-based closing wedge osteotomy, rotating the distal fragment internally, and utilizing the blade plate to create valgus. Valgus correction can be incorporated into the osteotomy to correct the medial displacement of the epiphysis. The osteotomy was designed to correct the retroversion deformity, improve hip motion and mechanics, and decrease the incidence of osteoarthritis. The retroversion deformity seen in late SCFE may cause anterior femoroacetabular impingement through a cam type mechanism, which may contribute to the early development of osteoarthritis.
21
Q
What are the complicates of surgery?
A
-
Osteonecrosis of femoral head
- Most common complx
- increased with unstable slip-47%
- hardware in postsuperior femoral neck-> ON as can damage the lateral circumflex artery ( supply head 2-4yrs) medial circumflex majority of femoral head >4 yrs
-
Chrondrolysis
- unrecognised implant penetration of articular surface
- associated spica cast immobilisation
- decreased with modern II
-
Residual Proximal Femoral Deformity and LLD
- increased alpha angle assoc w symptomatic impingement
- because prox femur fails to remodel
- tx- subtrochanteric osteotomy
- Slip progression- 1-2% after single screw fixation
- Hip stiffness
- Degenerative arthritis
- Pin associated Proximal femoral fracture
