Aims

To evaluate how abnormal proximal femoral anatomy affects different femoral version measurements in young patients with hip pain.

Introduction

Hip dysplasia is the most common congenital deformity of the musculoskeletal system. This is a pathology that brings the hip joint from subluxation to dislocation.

Frequency of hip dysplasia − 16 children per 1000 newborns.

Aims: The late effect of intramedullary nailing of the femur on proximal femur growth, particularly on growth plate of the greater trochanter and femoral neck, being known that losing the balance in the growth of the three ossiþcation points of the femurñs proximal extremity, the gap canñt be compensated by the greater trochanterñs remaining growth cartilage. Methods: During 1980–1995 we have performed 55 intramedullary femoral osteosyn-theses using KŸntscher rods in children 5–14 years of age. We have had the opportunity to observe 29 children during their later somatic growth: 25 femoral diaphyseal fractures and 4 non-unions. The average folow-up period has been 8.3 years. The patientñs average age has been 9,5 years. The hips were evaluated clinically for walking, mobility, limb length discrepancy. Radiological evaluation was based, according to Edgren, on following parameters of the joint architecture: cervico-diaphyseal angle (CDA), articulo-trochanteric distance (ATD), intertro-chanteric distance (TTD), femoral neck diameter (FND). Results: Clinical, one child presented 1.3 cm femur shortening. The evaluation of the radiological parameters on coxo-femoral joint showed increased CDA value between 10–30¡ in 8 children, increased ATD value (10–20mm) in 7 children, reduction of the TTD value in 6 patients and reduction of the FND (5–10mm) in 3 children. Conclusions: Insertion of intramedullary nail via the greater trochanter should be avoided in children less than 13–14 years of age, having tardy valgus effect and thinning of the femoral neck. We recommend osteosynthesis with plate and screws or, in little ones, transfragmentar screws, followed by immobilisation in plaster cast.

The direct anterior approach (DAA) is a popular minimally invasive approach for total hip arthroplasty (THA). It usually involves ligation of the lateral femoral circumflex artery's ascending branch (a-LFCA), which contributes to the perfusion of the tensor fasciae latae (TFL) muscle. Periarticular muscle status and clinical outcome were assessed after DAA-THA after a-LFCA preservation versus ligation. We evaluated surgical records of 161 patients undergoing DAA-THA with tentative preservation of the a-LFCA by the senior author between May and November 2021. Among 92 eligible patients, 33 (35 hips) featured successful preservation, of which 20 (22 hips, 13 female) participated in the study. From 59 patients with ligated a-LFCA, 26 (27 hips, 15 female) were enrolled, constituting the control group. MRI and clinical examinations were performed at 17–26 months to analyze volume and fatty infiltration of the TFL, gluteus medius and gluteus minimus muscles relative to the contralateral non-THA hip (15 preserved, 18 ligated). Clinical and radiographic data was retrospectively extracted from patient files. Patient-reported outcomes (PROMs) were added from the THA registry. There was a relative difference in TFL muscle volume of -6.27 cm. 3. (−9.89%, p=0.018) after a-LFCA preservation versus -8.6 cm. 3. (=11.62%, p=0.002) after ligation, without group differences (p>0.340). a-LFCA preservation showed lower relative TFL fatty infiltration (p=0.10). Gluteal muscle status was similar between sides and groups. Coxa valga morphology was more frequent in a-LFCA preservation (83%) than ligation (17%). Clinical outcomes showed high patient satisfaction in both groups, without difference in PROMs, but less anterolateral soft-tissue swelling after a-LFCA preservation (p<0.001). Despite excellent clinical results in both groups, preservation of the a-LFCA was associated with less TFL fatty infiltration and soft tissue swelling. Provided there is no compromise of intraoperative access we recommend a-LFCA preservation for DAA-THA

In early secondary arthritis due to femoral dysplasia, varus osteotomy achieves a control of arthritis for two decades in 80 % of cases : it is therefore a very reliable conservative treatment. Moreover, in carefully selected cases of severe arthritis in young active patients, a valgus osteotomy can achieve pain relief for a decade in 70 % of cases. THE VARUS OSTEOTOMY is recommended when the arthritis is due to a coxa valga ≥ 140°. By reducing the inclination angle to 125° the abductors level of arm is optimized, and their contracture is decreased. Therefore, the osteotomy reduces the surface strains, but it does not improve the extent of articular surfaces. A – . INDICATIONS. 1) Four factors are mandatory to achieve long term improvement:. The arthritis must be the . consequence. of the dysplasia, with degenerative changes localized at the supero lateral part of the head and of the acetabulum. This can be confirmed by isotope scanning. If the arthritic changes are not localised the desease is rather a primary arthritis, or an inflammatory or a metabolic disease, which are not an indication for a biomecanical treatment. There must be a real . coxa valga. , evidenced by coxometry. Anteversion is mesured by CT scan, and the inclinaison is mesured on a X ray of the pelvis with the hips in internal rotation equal to the ante-version. If there is a shortened femoral neck (such as a post reduction osteonecrosis), the modification of the glutei lever of arm may not change significantly the articular strains, and therefore osteotomy is no indicated. The articular . congruency. must not be impaired by the reduced inclination angle. Pre operative X rays with the hips in an abduction equal to the planned varisation must not reveal any lateral narrowing of the joint space, which would mean incongruity, and lead to failure. The possibility of articular . healing. must be important : varus osteotomy is recommended before 45 years, and if the joint space remains ≥ 50 % of normal. 2) Therefore varus osteotomy is . not recommended. in a non symptomatic dysplasia (as some of them may not lead to arthritis), or if the symptoms are those of a labrum syndrom, with suddent pain, instead of a progressive and mechanical arthritic pain. if the dysplasia is only acetabular : then only the acetabulum has to be treated. if the anatomic abnormality is not an increase of the inclinaison (neck-shaft) angle, but a modification of the head-neck angle, which causes impigement with the labrum, and which is not improved by inter-tro-chanteric osteotomy. 3) The . assosciated dysplasia. have to be taken into consideration. If there is a femoral hyperanteversion there are two different conditions in the adult :. if the patient walks with internal rotation of knees (convergent strabismus of patella), realising a dynamic correction of hyperanteversion, the association an external rotation of the femur to the varisation is recommended. but if, despite hyperanteversion, walking is without abnormal rotations of the knees, this means that the optimum congruity of the hip is in that position. An ostotomy is no advocated as, instead of retroversing the femoral neck, it would rotate externally the femoral shaft. If there are both an acetabular and a femoral dysplasia, they both have to be treated :. if an augmentation is recommended for an anterolateral defect, the shelf osteoplasty can be performed in the same operation that the varus osteotomy. if a medialisation is necessary (Chiari), both osteotomies can be assosciated in one stage. but if a complex reorientation osteotomy is necessary (either periacetabular –Giacometti-,. or pelvic –Ganz-), it could be hazardous to perform a varus osteotomy at the same time. B – . SURGICAL TECHNIC. The importance of the varisation depends on that of the coxa valga. The final inclinaison angle must be 125°, as the lever of arm of the abductors is impaired for a lower angle. Moreover there is a post operative limping due to the ajustement of the glutei length, the duration of which is function of the varisation (one year per 10°). To reduce this limping, only the necessary varisation has to be made. The technic has several important points :. non union is avoided by non dissection of the medial metaphysis or removal of a wedge :. we use a subperiosteal osteotomy, leaving in contact the medial cortex, with a lateral opening, fixed by a nail plate as a tension band. This technique gives a minimum limb shortening (12 mm for 15° varisation). respect of the articulation and soft tissues. There is no arthrotomy as the nail plate is inserted on a guide pin. Later implantation of the THR will not be complicated by the previous osteotomy. precise, « automatic » correction, depends only on the nailplate angle. the resistance of the osteosynthesis allows immediate rehabilitation (this extra articular operation does not reduce ROM), and 10 to 20 kilos weight bearing. Full weight bearing is authorized at three months. C – . RESULTS. There are less thant 5 % mechanical complications. An antalgic effect is obtained within some weeks. In 80 % of cases, painlessness and absence of radiological deterioration for two decades is achieved, a THR becoming necessary in the third decade. In 20 % of cases, only a temporary effect is obtained, leading to a THR after 5 to 10 years. THE VALGUS OSTEOTOMY is at present used in only seldom cases of young patients with a severely damaged articulation, but who prefer an antalgic conservative surgery than a THR, because they wish to continue for a decade a strenuous activity not compatible with an arthroplasty. This can be made only when there are two large osteophytic drops of the acetabulum and of the femoral head, which can be put into contact by the valgisation, and facilitate healing of the superior lesions. In carefully selected cases, a relief of pain is achieved for a decade in 70 % of patients. IN CONCLUSIONS. The femoral varus osteotomy remains one of the most reliable conservative operations in osteoarthritis due to DDH. However to achieve these good results, a clear understanding of the indications and biomechanical demands of this operation is required. In seldom and selected cases of severe arthritis, a palliative valgus osteotomy can achieve a decade of pain relief

Introduction and Aims: The treatment of femoral shaft fractures in skeletally immature patients has changed dramatically over the past 30 years. This is due in part to the advances in intramedullary nail outcomes pioneered in the adult orthopaedic trauma literature. We examined the results of reamed, locked nails in a pediatric population. Method: The medical records of 224 children with femoral shaft fractures treated with reamed, locked intramedullary nails (RLIMN) at our institution between 1987 and 2000 were reviewed (largest series in the literature). Patients were treated with nails placed through the greater trochanter. Of those patients, 72 patients had long-term clinical (> 24 months) and radiographic (AP pelvis and leg length CT scanogram) follow-up. Functional status and radiographic parameters (femoral neck-shaft angle, leg length, presence of osteonecrosis) were recorded. Patients lacking two-year clinical and radiographic follow-up were evaluated via telephone follow-up. Results: At our institution, over 200 skeletally immature patients have successfully undergone reamed, locked, intramedullary nailing of femur fractures. Average age at the time of treatment was 10.3 years. No case of osteonecrosis of the femoral head occurred. All fractures united after treatment with RLIMN at an average of 71 days. No patient manifested a gait abnormality after healing. Complications included delayed union in two patients, (one patient was treated with exchange IMN and one patient healed after dynamisation) superficial wound infection in one patient, (treated with oral antibiotics) and coxa valga in one patient. The patient that developed coxa valga was 7.7 years old at the time of intramedullary nailing. The only other procedures performed were removal of hardware in patients who remained skeletally immature at the time of healing. All patients returned to pre-injury activity level. The average leg length difference was 0.6cm (longer on the injured extremity). Average articulo-trochanteric distance was 0.28cm (longer on injured extremity). Conclusion: Our results demonstrate that femoral shaft fractures in skeletally immature patients can be safely treated with reamed, locked intramedullary nails placed through the greater trochanter. We recommend careful placement of the nail through the greater trochanter to avoid damage to the blood supply of the femoral head

Introduction: For longer lasting and bone conserving cementless stem fixation, stable and physiological proximal load transfer from the stem to the canal should be one of the most essential factors. According to this understanding, we have been developing a custom stem system with lateral flare and an off-the-shelf (OTS) lateral flare stem system was added to the series. On the other hand, dysplastic hips are often understood that they have larger neck shaft angle as well as larger anteversion. In other words they are in the status called “coxa valga.” From this point of view we had been mainly using custom stems for the dysplastic cases before. After off-the-shelf lateral flare stem system; which is designed to have very high proximal fit and fill to normal femora; was added, we have been using 3D preoperative planning system to determine custom or OTS. Then in most of the cases, OTS stem were suitably selected. Our pilot study of virtual insertion of OTS lateral flare stem into 38 dysplastic femora has shown very tight fit in all 38 cases. The reason was analyzed that the excessive anteversion is twist of proximal part over the distal part and the proximal part has almost normal geometry. In the present study, 59 femora were examined by the 3D preoperative planning system how the excessive anteversion effect to the coxa valga status. Materials and Methods: Fifty-nine femoral geometry data were examined by the 3D preoperative planning system. Thirty-three hip arithritis, 3 RA, 2 metastatic bone tumours, 5 AVN, 1 knee arthritis, 12 injuries, and 3 normal candidates were included. Among them one arthritic Caucasian and one AVN South American were included. The direction of the femoral landmarks; centre of femoral head (CFH), lesser trochanter (LTR), and asperas in 3 levels (just below LTR, upper 1/3, mid femur; A1-3); were assessed as the angle from knee posterior condylar (PC) line. Neck shaft angle of each case was assessed from the view perpendicular to PC line and neck shaft angle form the view perpendicular to CFH and femoral shaft (i.e. actual neck shaft angle). Results: Average anteversion was 34.4 +/−9.9 degree. CFH and LTR correlated well (i.e. they rotate together). A1, A2, A3 correlated well (i.e. they rotate together). LTR and A1 correlate just a little, LTR and A2 were independent each other. So the twist existed around A1. Neck shaft angle was 138.7+/−6.6 in PC line view and in actual view 130.3+/−4.4. No excessive neck shaft angle was observed in actual view. Even the case that has the largest actual neck shaft angle (140.4), the virtual insertion showed good fit and fill with the lateral flare stem. Conclusion: In many high anteversion cases, coxa valga is a product of the observation from non perpendicular direction to CFH-shaft plane. Selection or designation of the stem for high anteversion cases should be carefully determined by 3D observation

Developmental dysplasia of the hip (DDH) represents a heterogeneous group of deformities that are commonly associated with secondary osteoarthritis. Affected hips may require total hip arthroplasty (THA) for endstage disease and these cases can present unique challenges for the reconstructive surgeon. While the severity of deformity varies greatly, optimizing THA can be challenging even in the “mildly” dysplastic hip. These disorders are commonly characterised by acetabular deficiency with inadequate coverage of the anterolateral femoral head and proximal femoral abnormalities including excessive femoral antetorsion, coxa valga and femoral stenosis. In more severe cases, major femoral head subluxation or dislocation can add additional complexity to the procedure. In addition to the primary deformities of DDH, secondary deformities from previous acetabular or proximal femoral osteotomies may also impact the primary THA. Primary THA in the DDH hip can be optimised by detailed understanding of the bony anatomy, careful pre-operative planning, and an appropriate spectrum of techniques and implants for the given case. This presentation will review the abnormal hip morphologies encountered in the dysplastic hip and will focus on the more challenging aspects of THA. These include acetabular reconstruction of the severely deficient socket and in the setting of total dislocation, femoral implant procedures combined with corrective osteotomy or shortening, and issues related to arthroplasty in the setting of previous pelvic osteotomy. Despite the complexity of reconstruction for various dysplastic variants the clinical outcomes and survivorship of these procedures are good to excellent for most patients. Nevertheless, more complex procedures are associated with an increased complication rate and this should be considered in the surgical decision-making process

The use of conventional stems in hip arthroplasty may be difficult in cases of dysplasia, coxa vara or coxa valga, after fracture or proximal femur osteotomy. In fact the morphologic alterations of the proximal femur might require prosthetic components characterised by small size and different neck angles to restore correct joint biomechanics. In these cases we are often compelled to compromise between the ideal implant aneiversion and fit and what we can really achieve. An alternative to conventional prostheses is represented by custom-made prostheses. For 3 years we have been using the Modulus stem in the treatment of morphologic disorders of the hip. The conic shape of the stem easily fits the different morphologies of the proximal femur, whereas the modularity of the neck makes it possible to correct length, inclination and declination of the femural neck. We studied 59 patients by clinical and radiographic examination before surgery and 1, 3, 6 and 12 months postoperatively. We recorded a statistically significant improvement in the clinical score already at 1 month but this was even better at 6 months after surgery, with respect to the pre-operative examination. With the use of this prosthesis, the recovery of correct joint biomechanics together with high tribologic standards could improve the implant survival, leading to cost reduction and patient satisfaction

Proximal femoral deformity is common in children with cerebral palsy (CP), contributing to hip instability and ambulation difficulties. This population-based cohort study investigates the prevalence and significance of these deformities in relation to Gross Motor Function Classification System (GMFCS) level. Children with a confirmed diagnosis of CP born within a three-year period were identified from a statewide register. Motor type, topographical distribution and GMFCS level were obtained from clinical notes. Neck Shaft Angle (NSA) and Migration Percentage (MP) were measured from an anteroposterior pelvis x-ray with the hips internally rotated. Measurement of FNA was by the Trochanteric Palpation Test (TPAT) or during fluoroscopic screening of the hip with a guide wire in the centre of the femoral neck. Linear regression analysis was performed for FNA, NSA and MP according to GMFCS level. 292 children were eligible. FNA was increased in all GMFCS levels. The lowest measurements were at GMFCS levels I and II p<0.001. GMFCS levels III, IV, and V were uniformly high p<0.001. Neck shaft angle increased sequentially from GMFCS levels I to V (p<0.001). This study confirms a very high prevalence of increased FNA in children with CP in all GMFCS levels. In contrast, NSA and MP progressed step-wise with GMFCS level. We propose that increased FNA in children with CP represents failure to remodel normal fetal alignment because of delay in ambulation and muscle imbalance across the hip joint. In contrast, coxa valga is an acquired deformity and is largely related to lack of weight bearing and functional ambulation. The high prevalence of both deformities at GMFCS levels IV and V explain the high rate of displacement in these hips and the need for proximal femoral realignment surgery in the prevention and management of hip displacement

The hip joints are commonly affected in Juvenile Idiopathic Arthritis (JIA) in childhood. Common features are pain, subluxation, femoral anteversion, coxa valga, significant fixed flexion deformity and a true arthritis, with loss of articular cartilage principally from the femoral head but also the acetabulum. In children with JIA, it is accepted that a medial soft tissue release of the hips, dividing adductor longus, adductor brevis and the ilio-psoas, is a useful tool in the management of significant hip joint involvement. The principal indication for surgery is the relief of pain, but other benefits are correction of fixed flexion deformity, restoration of articular cartilage, increased abduction of the hips and, in those children who are unable to walk, frequently a transition to the potential to walk. The procedure is nearly always performed bilaterally. Our study aimed to document the restoration of articular cartilage at the hips following soft tissue release. It has been noted in the literature that there is regrowth of articular cartilage in the hip but there has been no true documentation of this and x-ray studies are unreliable as the elimination of fixed flexion deformity can prejudice accurate analysis of femoral head geometry on 2 –dimensional views. We therefore carried out MRI scanning of the hips, immediately prior to the soft tissue release and 12–18 months post-operatively. In 10 consecutive patients analysed, scans demonstrated true articular cartilage regrowth in 8 cases. We thus conclude that soft tissue release of the hips in JIA is a useful management tool, and may to some extent reverse the severe articular cartilage loss seen in these children. The next stage of our study is to analyse the articular cartilage at the time of subsequent hip arthroplasty to determine whether true hyaline cartilage is reformed or whether the reconstitute represents fibrocartilage

Purpose of the study: Progressive excentration of the femoral head is fequent in the paralytic hip. The result can be dislocation with considerable functional impact even if the subject cannot walk. Once the dislocation becomes permanent,, treatment is difficult. Soft tissue surgery is insufficient. We present our experience with Chiari osteotomy in a series of 28 paralytic hips. Material and methods: This retrospective analysis included 28 paralytic hips which were operated on from 1974 to 2003. Fourteen patients had cerebral palsy and 14 a cord lesion. Mean age was 18.5 years (range 9–48) at the time of hip surgery. Mean postoperative follow-up was ten years. Prior hip surgery was noted in eleven cases and association with other bone and joint deformities was frequent: scoliosis, oblique pelvis. The Buly classification was noted for patient independence and was ≤ 2 preoperatively for seven patients. Flexion was greater than 80°. Preopeartive excentration was scored according to Reimers: luxation for ten hips and subluxation for 18. Acetabular dysplasia was present in all patients and 19 presented coxa valga. The femoral head was deformed in 14. The objective of the operation was to relieve hip pain and improve hip motion with a good acetabular cover. A chisel was used in all cases for the osteotomy: average 12° ascending cut medially. Associated procedures were: release (n=7), posterior block (n=2), femoral varus osteotomy (n=6), derotation osteotomy (n=6). Results and discussion: The effect was clearly beneficial in terms of pain relief. There were no stiff hips. No functional degradation was noted and there were no major complications. The Median Reimers index improved from 66% to 19%. Centering was perfect for nine patients and presented residual excentration > 30% for six. There were two cases of femoral head necrosis (on dislocated hips). Seven hips progressed to osteoarthritic degradation and one patient underwent a revision procedure at 14 years for a total hip arthroplasty. Conclusion: Chiari osteotomy enabled pain relief and improved function in most patients. It stabilized the hip even after dislocation if appropriate procedures are associated. At present however, for dislocated hips, total hip arthroplasty is often proposed. An associated oblique pelvis and scoliosis should be corrected for before surgical treatment of the hip

Introduction: Femoroacetabular impingement (FAI) is one of the main causes of hip osteoarthritis. Femoral retroversion has been reported as a cause of FAI and it is well established that a retroverted femur produces hip pain and alterations in the external and internal rotation balance. However, no studies of femoral retroversion in patients with FAI have been reported. Furthermore, since the lack of internal rotation is a common feature in patients with FAI, it could be possible that femoral version abnormalities are present in these patients. The purpose of this study is to describe the femoral version in a group of patients with FAI and to assess its relation in the development of hip osteoarthritis. Methods: The history, x-rays and hip CT scans of 142 patients with FAI were reviewed. All patients presented persistent hip pain and were evaluated clinically between January 2006 and July 2008. We defined FAI when at least one of the following features were present:. an abnormal alpha angle (> 49°) measured on the elongated femoral neck x-ray,. a positive cross-over sign or pro-trusio acetabuli in the AP pelvis x-ray,. the presence of diminished anteversion in the femur (< 10°) or a retroverted femur (< 0°) in the CT scan, associated with a positive hip impingement test and lack of internal rotation at 90 degrees of flexion. We documented the type of FAI, the presence of acetabular dysplasia, coxa valga, coxa vara and the femoral version measured on the CT scan. The degree of osteoarthritis of the hip using the Tönnis classification was documented as well. Results: Two hundred and sixty-five FAI hips from 142 patients (73 females and 69 males) were analyzed. The average age was 36.7 years. The mean femoral version was 11.4 ° (−14.1° to 47°). We found 43 hips (16.6%) of the femora were retroverted and 133 hips (50%) had either diminished anteversion (< 10°) or were retroverted. In 12 hips (0.05%) the only cause of FAI was the presence of a diminished anteversion or retroverted femur. The statistical analysis using the generalized estimating equations method including the right and left hips, shown that among these six predictors, both femoral retroversion (p=0.046) and coxa vara (p< 0.001) were statistically significant for the presence of osteoarthritis. Conclusion: The presence of a retroverted femur seems to be a cofactor in the development of hip osteoarthritis in patients with FAI. The orthopedic surgeons should be aware of the high frequency of femoral retroversion when evaluating patients with hip impingement, in order to make the right diagnosis and treatment. It might be possible that this association between FAI and femoral retroversion is due to a common hip disease during skeletal maturation (i.e. SCFE) leading to two anatomical alterations at the proximal femur: reduced head-neck offset and retroverted femur

In this paper operations are discussed that improve the dysplastic acetabular roof in developmental dislocation of the hip (DDH) of children up to 10 years. In the first year of life acetabular dysplasia can be treated successfully by flexion-abduction splints and plaster casts in „human position“. From the second year on, only slight dysplasias can heal spontaneously or be treated conservatively. Then the steep acetabular roof has to be osteotomized and levered down to a normal angle and coverage to avoid redislocation or residual dysplasia. Different procedures have been described in the course of time. Two osteotomies are chiseling in the anterior to posterior direction. Salters innominate osteotomy levers the whole acetabulum with the lower part of the pelvis in an anterolateral direction around an axis passing through the pubic symphysis and the posterior part of the osteotomy. In Pembertons osteotomy the hinge for turning down the acetabular roof is the last, posterior, transverse cortical segment over the tri-radiate cartilage, short before the sciatic notch. Osteotomies chiseling from lateral in medial direction have been described already by Albee (1915) and Jones (1920). Lance (1925) propagated this technique in Europe. Here the acetabular roof is partially osteotomized in a thickness of 5–7 mm. Only the lateral part of the acetabulum is brought into the horizontal position. Wiberg in 1939 used this technique, but in 1953 he was the first to publish a full osteotomy what Dega called 1973 a transiliac osteotomy. Dega had originally learned the technique of Lance, but in 1963 when he reduced high dislocations after the technique of Colonna, he performed also a full transiliac osteotomy. After the Symposium of Chapchal in Basel 1965 we started in Berlin also with the complete acetabular osteotomy. With the control of an image intensifier the blade of the osteotome is driven toward the posterior rim of the tri-radiate cartilage leaving only a small bony rim above. Anteriorly the blade passes through the ant. inf. iliac spine. Posteriorly it just enters the sciatic notch. Here we check the blade position by direct palpation. The acetabulum is bent down partly in the small rim of bone left and mainly in the triradiate cartilage. Angles up to 50° have been achieved, which you cannot reach by other techniques. In the beginning we have combined after Mittelmeier and Witt this acetabuloplasty with a varus osteotomy of the femur. In our long-time follow-up (Brüning et al. 1988,1990) however, we found in almost 50% a subcapital coxa valga or a so-called head-in-neck-position of the femoral head. Then we avoided varusosteotomies and had good results without it (Pothmann). To keep the acetabular roof in the new position we used first bone wedges from the varus osteotomy, then deproteinized bone wedges from animals, and today deep frozen wedges of human femoral heads of the bone bank, sterilized at 121 degrees C for 20 min. (Ekkernkamp, Katthagen). A firm layer of cortical bone laterally is necessary. Reinvestigations have proven the stability of this material too ( Pothmann). This type of acetabular osteotomy in our and other authors opinion is the best. Salters osteotomy is not as efficient in severe dysplasia. And in older children it produces a decrease in anteversion of the acetabulum, which may limit internal rotation of the hip and cause osteoarthritis if it does not improve. In Pembertons osteotomy one cannot use the image intensifier, which is of great help to perform the osteotomy exactly and also the levering of the acetabulum to the optimal coverage. Our first long-time follow-up of children with additional varus-osteotomies (Brüning et al.) reviewed 90 hip joints in 67 children. The age at operation was in average 3.6 years, the age at follow-up 15 years. Clinical results. 98% of the patients had no pain or only occasional, no limitation of movement and normal or almost normal gait. The Trendelenburg sign was negative in 71% of the cases, grade 1 in 15.5% and grade 3 in 13.5%. Radiological evaluation. The mean value of the AC-angle (acetabular index) preoperatively was 33.8°, postoperatively normal with 16.3°. The acetabular angle of the weightbearing zone was at follow-up 9.7°, which is normal too. At the age of less than 18 years the CE angle of 25,9° was normal too, as well the instability (protrusion) index of Reimers of 12.3 % and the distance femoral head to teardrop figure with 8.8 mm. In our study group of hip dysplasia we introduced a score of normal values of hip measurements and 3 grades of deviation from normal, slightly pathological, severely pathological and extremely. When we counted normal values and slightly pathological ones together as a good result, we found for the different measurements of the acetabulum percentages mainly between 82 and 93 %. Remarkable were two measurements of the femoral neck, the epiphyseal index with only 50 % of normal and slightly pathological angles and the head-neck index with 47.7% respectively. This was due to the head-in-neck position of the femoral neck after varus osteotomy as we have mentioned already. Acetabular coverage is achieved best in transiliac osteotomies up to 10 years. Then, only by triple pelvic osteotomies the acetabulum in total can be redirected to a normal coverage. But this operation is more difficult. Residual dysplasias therefore should be treated as early as possible in the way demonstrated here

Purpose of the study: The design of the NANOS femoral stem defined in 2002 is based on anatomic studies and the analysis of 578 scanner slices. The stem is plasma torch coated with titanium and with calcium phosphate to accelerate the osteointegration process. The NANO stem is indicated for young active patients with BMI < 30 and free of coxa vara/valga. Material and methods: This was a multisite study conducted in five hospitals and including 205 patients; follow-up was 12 months for 77 patients and 24–36 months for 50. For the patients followed for 12–24 months, indications were: primary degenerative disease (n=110, 51.4%), dysplasia (n=57, 26.6%), necrosis of the femoral head (n=32, 15%), other causes including Perthes disease, epiphysiolysis, posttraumatic osteoarthritis, protrusion. Mean patient age was 57.4 years (33–80). There was no case of stem migration or dislocation. Results: Mean mobility (Merle-d’Aubigné) was 5.49 in 205 patients preoperatively, 5.97 in 73 patients at 12 months and 6.6 in eight patients after 18 months. Pain and walking were scored 7.51 (Merle-d’Aubigné) in 205 patients preoperatively, 11.7 in 77 at 12 months, then 11.96/12 at 24–36 months. The HSS score improved from 47.8/100 preoperatively to 96.62/100 at 24–36 months (50 patients). Outcome was good in more than 280 implants, mainly inserted via an anterolateral approach. Discussion: Biomechanical studies have demonstrated the advantages of implanting the NANOS prosthesis via a MIS approach: mini-incision, net diminution of undesirable stress. The partially spared femoral neck can be used as an anchorage zone, favouring primary stability. The fine neck of the NANOS stem avoids impingement and increases joint range of motion. Conclusion: The early results indicate a high level of patient satisfaction and the clinical and radiographic findings suggest good long-term outcome can be expected

Objectives

There are several reports clarifying successful results following open reduction using Ludloff’s medial approach for congenital (CDH) or developmental dislocation of the hip (DDH). This study aimed to reveal the long-term post-operative course until the period of hip-joint maturity after the conventional surgical treatments.

Femoroacetabular impingement (FAI) causes pain and chondrolabral damage via mechanical overload during movement of the hip. It is caused by many different types of pathoanatomy, including the cam ‘bump’, decreased head–neck offset, acetabular retroversion, global acetabular overcoverage, prominent anterior–inferior iliac spine, slipped capital femoral epiphysis, and the sequelae of childhood Perthes’ disease.

Both evolutionary and developmental factors may cause FAI. Prevalence studies show that anatomic variations that cause FAI are common in the asymptomatic population. Young athletes may be predisposed to FAI because of the stress on the physis during development. Other factors, including the soft tissues, may also influence symptoms and chondrolabral damage.

FAI and the resultant chondrolabral pathology are often treated arthroscopically. Although the results are favourable, morphologies can be complex, patient expectations are high and the surgery is challenging. The long-term outcomes of hip arthroscopy are still forthcoming and it is unknown if treatment of FAI will prevent arthrosis.