Epiphyseal capitis femoris
The slipped capital femoral epiphysis (ECF) ( epiphysis of the femoral head , and occasionally inaccurate teenagers Slipped Capital Femoral Epiphysis called) is an orthopedic disease at the hip joint . In the upper epiphyseal plate of the femur , the epiphysis separates from the metaphysis .
The ECF only occurs in children because in them the cartilaginous growth plate ( epiphyseal plate ) between the epiphysis and metaphysis is still growing and is therefore unstable. Typical age of onset is 10-14. Years of age, boys are affected three times more often than girls.
Around 0.2–1 child per 100,000 are affected worldwide. The highest incidence is found among the Maori in New Zealand. However, a slight sliding of the femoral head without a complete solution seems to be much more common than previously assumed. In a study of over 2,000 young, fully grown and healthy Norwegians (58% women), sliding was found in 6.6% with an increased lateral head shaft angle according to Southwick (≥ 13 °).
Many of the children affected are overweight, although if they are significantly overweight, a so-called dystrophia adiposo-genitalis or Fröhlich syndrome was previously assumed. A predominance of the growth hormone somatotropin over the sex hormones was also assumed, whereby increased growth leads to a loosening of the growth plate. However, evidence of a hormonal disorder could only be provided in a few individual cases. The actual cause is still unknown.
Due to the inclined position of the epiphyseal plate for weight loading by the trunk area, there is a corresponding typical shift; the epiphysis slides downwards (varus malposition) and backwards (retrotorsion). If left untreated, this can later lead to a coxa vara retrotorta.
Three forms can be distinguished according to the dynamics of the sliding process:
- If the displacement of the epiphysis occurs gradually, one speaks of the "lenta shape"
- If the slide suddenly occurs as a painful event, it is an "Acuta form"
- Both combined, that is, an acute event with a pre-existing gradual shift is called "acute to chronic".
Hip pain is generally felt in the groin , but can also be projected onto the knee , especially in children (this is related to the course of the obturator nerve ). In addition, with the ECF there is the joint position in external rotation and abduction, which is caused by the joint effusion, which increases with flexion ( Drehann's sign ). The diagnosis is very often delayed because hip and knee problems in children are often misinterpreted. Typical preliminary diagnoses are then: hip runny nose , groin strain , overload. An important differential diagnosis , which can be differentiated very reliably by X-ray, is Perthes' disease , also an orthopedic hip disease in children.
The detachment of the joint head cannot always be seen clearly on an x-ray of the hips, especially a pelvic overview. It is therefore important to have an additional axial image in Lauenstein projection on both sides, on which the misalignment of the epiphysis can be clearly recognized. The slip angle is determined on this recording. There are therapeutic consequences from this angle.
Since this is not a local occurrence on one hip, but both sides grow to the same extent and the epiphyses are at risk of dislocation, both sides must also be examined radiologically.
Surgical fixation is necessary in order to avoid possible femoral head necrosis and to ensure that the affected joint can withstand stress later. In young patients with still significant residual growth, drill wires are used for this purpose, which are pushed through the growth plate into the epiphysis parallel to the femoral neck. In the event of significant acute slippage, the femoral head must first be repositioned by internal rotation and traction. In older children without significant residual growth ( Y-joint already closed), screws with a short thread are inserted into the femoral head in the same direction. The procedure is called epiphysodesis , the growth plate is stabilized by bridging. After the growth is complete, the osteosynthesis material (wires or screws) is removed.
The risk of epiphysolysis also occurring in the other femoral head is 16-60% and is particularly higher in girls and with early onset. Therefore, whether prophylactic epiphysodesis should be performed on the healthy opposite side is controversial, but it is common in many centers in order to be able to prevent later slipping. The determination of the " posterior sloping angle ", which can be measured on oblique images (" frog-leg view ") of the hip joint and was first described in 2005, can be helpful for the decision . This is the angle between a perpendicular on an axis along the axis of the femoral shaft and a line connecting the two outer corners of the epiphysis. In a New Zealand study on 132 patients, an angle above 14 ° was found to be a well-suited limit, above which prophylactic epiphysodesis was recommended (sensitivity 83%, specificity 79%).
- Jörg Gekeler: The femoral head epiphyseal solution (= orthopedic surgeon's library. Volume 19). Ferdinand Enke Verlag, Stuttgart 1977, ISBN 3-432-89571-2 .
- Peter Engelhardt: Juvenile femoral head solution and coxarthrosis. (= Orthopedic surgeon's library. Volume 39). Ferdinand Enke Verlag, Stuttgart 1984, ISBN 3-432-94011-4 .
- Carl Joachim Wirth: Practice of orthopedics. Georg Thieme Verlag, Stuttgart / New York 2001, ISBN 3-13-125683-4 .
- TG Lehmann, I. Ø. Engesæter, LB Laborie, SA Lie, K. Rosendahl, LB Engesæter: Radiological findings that may indicate a prior silent slipped capital femoral epiphysis in a cohort of 2072 young adults. In: The Bone and Joint Journal. 2013; Volume 95-A, Issue 4, April 2013, pp. 452–458. ( doi: 10.1302 / 0301-620X.95B4.29910 )
- F. Hefti: Pediatric Orthopedics in Practice. Springer, 1998, ISBN 3-540-61480-X .
- Paul M. Phillips, Joideep Phadnis, Richard Willoughby, Lyn Hunt: Posterior Sloping Angle as a Predictor of Contralateral slip in Slipped Capital Femoral Epiphysis. In: Journal of Bone and Joint Surgery. 2013, Volume 95-A, Issue 2, January 16, 2013, pp. 146–150.