Сompletely slipped capital femoral epiphysis in an 11 year old girl successfully treated bu DUNN ’s open reduction through GANZ ’ surgical dislocation of the hip (clinical case)

Slipped capital femoral epiphysis (SCFE) is a hip condition that occurs in teens and preteens who are still growing. Treatment for SCFE involves surgery to stop the head of the femur from slipping any further. Without early detection and proper treatment, SCFE can lead to potentially serious complications, including rapid degeneration of the femoral head and/or painful arthritis in the hip joint. Objective. Our case is presented to familiarize with the technique of safe surgical hip dislocation for the treatment of intraarticular hip pathologies. Case report and Methods. After collision while playing the 11 year old girl developed left hippain still allowing to walk. Imaging documented an acute slipped femoral capital epiphysis with the metaphysis articulating against the acetabulum. The patient was underwent open reduction could be performed us-ing the DUNN procedure modified by GANZ. 6 weeks later prophy - lactic screw stabilization of the healthy right hip followed. Results. At 9 months follow-up the patient walks painfree with symmetric range of motion. Conclusion. The goal of treatment is to prevent the mildly displaced femoral head from slipping any further. This

Slipped capital femoral epiphysis (SCFE) is a hip condition that occurs in teens and preteens who are still growing.Treatment for SCFE involves surgery to stop the head of the femur from slipping any further.Without early detection and proper treatment, SCFE can lead to potentially serious complications, including rapid degeneration of the femoral head and/or painful arthritis in the hip joint.Objective.Our case is presented to familiarize with the technique of safe surgical hip dislocation for the treatment of intraarticular hip pathologies.Case report and Methods.After collision while playing the 11 year old girl developed left hippain still allowing to walk.Imaging documented an acute slipped femoral capital epiphysis with the metaphysis articulating against the acetabulum.The patient was underwent open reduction could be performed using the DUNN procedure modified by GANZ.6 weeks later prophylactic screw stabilization of the healthy right hip followed.Results.At 9 months follow-up the patient walks painfree with symmetric range of motion.Conclusion.The goal of treatment is to prevent the mildly displaced femoral head from slipping any further.This is always accomplished through surgery.Early diagnosis of SCFE provides the best chance of stabilizing the hip and avoiding complications.When treated early and appropriately, long-term hip function can be expected to be very good.Once SCFE is confirmed, the child will not be allowed to put weight on their hip and will be admitted to the hospital.In most cases, surgery is performed within 24 to 48 hours.In patients with unstable SCFE, the surgeon may first make an open incision in the hip, then gently manipulate (reduce) the head of the femur back into its normal anatomic position.The surgeon will then insert one or two metal screws to hold the bone in place until the growth plate closes.Sometimes surgeon may recommend inserting a screw into the unaffected hip at the same time to reduce the risk of SCFE.

Introduction
Slipped Capital Femoral Epiphysis (SCFE) is a pathology developing during the pubertal growth spurt [3] presenting with a broad spectrum of severity [1].Accordingly treatment has to be individualized [2].The goal of treatment is to prevent secondary coxarthrosis, which in mild slips is best achieved by in-situ pinning to prevent further increase of displacement [19], combination with Imhäuser-Southwick intertrochanteric osteotomy on more severe slips [4], or direct reduction of the slipped epiphysis to restore anatomy as first described by DUNN [1].Dunn's procedure has been critisized since his publication, as subsequent authors experienced high rates of for femoral head necrosis.The major point to reduce the risk of femoral head necrosis has been outlined by DUNN [1] in describing, how to protect the important branches of the medial femoral circumflex vessels to the femoral head, which probably had not been adhered to in the failed cases.
Extensive studies of the vascular anatomy [6,7,10] have led Ganz to develop his technique of safe surgical hip dislocation [5] to treat problems not accessible by closed means.Fig. 1 illustrates the normal anatomy of the vessels to the epiphysis in an eleven year old girl.
Surgical dislocation of the hip combined with DUNN's principles has been introduced by Ganz for reduction of the femoral head in severe cases of slipped capital femoral epiphysis to restore the hip anatomy [8,15].
With the case report we wish to draw attention to this procedure not only to restore anatomy in cases of severe SCFE but also to familiarize with surgical hip dislocation to assess pathology as e.g.tumors around the coxal femoral end and the actebalum.

Material and Methods
The work was performed in compliance with the current legislation and the article was approved at a meeting of the Bioethics Committee of the Western Ukrainian Specialized Children's Medical Center (Protocol № 93 dated 12.12.2023).
The healthy well proportionate 11 year old premenarchal girl had first mild pain of the left hip after collision with a class mate, but could still walk well.About 4 weeks later she suffered acute incapacitating pain making it impossible to stand and walk.CTimages showed the completely dislocated femoral epiphysis (SCFE) with the femoral neck metaphysis articulating against the acetabulum (fig.2).
Two weeks later October 5 th , 2022 open reduction of the epiphysis was performed though GANZ' hip dislocation.
Surgical technique followed strictly the steps described in detail [15]; the illustrations herein shall just assist in understanding the critical steps of the procedure (fig.3).
The patient is positioned in the lateral decubitus and leg and hip are prepped with betadine solution (fig.4, a).Through a straight lateral incision the anterior margin of the m.gluteus maximus is identified and the posterior borders of m. gluteus medius and m. vastus lateralis with their insertions/origin of trochanter maior are exposed and a sagittal osteotomy of the trochanter maior is performed leaving the insertions of m. gluteus medius and m. vastus lateralis en bloc with the osteotomized trochanter (fig.3, a).K-wire insertion and image intensifier control may be used to determine the correct osteotomy plane as the trochanteric insertion of m. piriformis protecting the femoral head vessels should not be released from the femur.By retracting the m.luteus-medius -trochanter -m.vastus lateralis compound medially the hip capsule is exposed.Hohmann retractors are inserted.The hip capsule is incised as shown in (fig.3, b) antero-lateral strictly along the labrum to avoid injury to the vessels, then along the femoral neck leaving an anterior flap.
The joint is now inspected and a cuneiform segment is resected from the metaphysial femoral stump to shorten the femoral neck as advised by Dunn not to rupture the medial gluteal vessels shortened by the time interval between slip and surgery.It is advisable to transfix the femoral epiphysis against the femoral neck with a K-wire (fig.4, b) in order to dislocate this bloc out of the acetabulum by externally rotating, abducting and flexing the leg.The femoral epiphysis is now carefully reduced anatomically upon the shortened femoral stump and transfixed with 2 screws.A small drill hole in the femoral head documents persistent blood flow (fig.4, c).
Following reduction of the hip the maior trochanter is stabilised by 2 lag screws.The patient was mobilized with crutches for partial weight bearing to full weight bearing following prophylactic transfixation of the right hip 7 weeks later November 24 th , 2022.At last follow-up in July 2023 the patient was painfree, fully active with symmetric range of hip motion.X-Ray documents the restored anatomy except shortening as expected without signs of femoral head necrosis (fig.5).

Results and Discussion
Surgical hip dislocation developed by Ganz is a technique allowing to treat pathologies of the acetabulum, femoral head and femoral neck otherwise not accessible.It needs to strictly adhere to the principles protecting the vascular supply of the branches of the medial femoral circumflex artery to the femoral head, as contribution of the ligamentum capitis femoris vessels and the lateral femoral circumflex artery are unfortunately negligible.
Dunn's method with careful exposure and shortening of the femoral neck has been frequently criticized in spite of excellent results in experienced hands [1,17,18].With the introduction of surgical hip dislocation Dunn's method to control the vascular supply to the femoral head is greatly facilitated.However, it needs to strictly follow an anatomic approach especially respecting the medial femoral circumflex vessels by respecting the protective insertion of the m.piriformis and correctly positioning the Z-shaped capsular incision as described by [15] and shown in fig 3. Furthermore the anteromedial posterolateral periosteal flaps around the femoral neck have to follow Dunn's description [1].
The indication for open reduction of SCFE needs careful evaluation in the light of good results achieved by in situ pinning or additional intertrochanteric corrective osteotomy as femoral head necrosis in SCFE has never been reported without operative intervention.
The case presented to our understanding would not have been manageable without reduction of the slipped femoral head.
Prophylactic fixation of the contralateral hip in SCFE is controversially discussed regarding indication as well as technique [15,16].Factors as body mass, age, type of slip, sex have an influence on the risk for contralateral slipping of SCFE.If carefully done we consider the risk of prophylactic stabilization of the unslipped contralateral hip low and generally recommend it as it was done in the presented case.

Conclusion
Surgical hip dislocation to done according to Ganz principles is a valuable technique to approach intraarticular hip pathologies and can restore the anatomy in severe slipped capital femoral epiphysis as illustrated in the presented case.

Fig. 1 .Fig. 2 .Fig. 3 .
Fig. 1.Deep terminal synovial branches of the medial femoral circumflex vessels to the femoral head in an 11 year old girl exposed for surgical hip dislocation to remove an acetabular tumor.The incision follows antero-later the labrum

Fig. 4 .Fig. 5 .
Fig. 4. The patient is positioned in the lateral decubitus (a).The leg is prepped completely for free mobility.The straight lateral incision is marked (b).For dislocation of the epiphysis out of the acetabulum after shortening of the femoral neck a K-wire is inserted to avoid tearing the medial femoral circumflex vessels (c).The femoral head is anatomically repositioned and already transfixed with 2 screws.A drill hole into the femoral head shows blood flow