Coxa Valga Research Articles

Are hips stable in children with cerebral palsy?

This commentary is on the original article by Terjesen on pages 951-957 of this issue. In 2010, the mechano-biological principles of proximal femoral geometry and muscle forces were implemented on a three-dimensional finite element model of the proximal femur, in order to predict changes in morphology over time in both typically developing children and children with cerebral palsy (CP).1 The simulation relies on the assumption that cyclic octahedral shear stress promotes growth and cyclic hydrostatic compressive stress inhibits growth. This finite element model predicts an increase in femoral anteversion and coxa valga for load conditions in children with CP when compared with typically developing children. In this study, growth was simulated over a period of approximately 5 months. From three population-based studies2–4 we know that hip displacement is common in children with CP (with an overall incidence of approximately one-third); it is often present by 2–3 years of age; range of motion is a poor indicator of hips at risk; and it is directly related to gross motor function as graded by the Gross Motor Function Classification System (GMFCS). In these studies the cut-off values for the migration percentage were set at slightly different levels: 30–33% for hip subluxation and 90–100% for hip dislocation.2–4 In a new study, Terjesen has carefully evaluated and reported a population-based hip surveillance programme for children with CP in Norway.5 A large number of children (n=335) were included and the data were collected and analysed meticulously. Hip displacement occurred in 26% of all children (subluxation in 22% and dislocation in 4%) and in 63% of those at GMFCS levels IV and V. The mean migration percentage was 20.4% at the initial radiographs and 34.0% at the end of the study. The rate of increase in migration percentage increased with decreasing functional level, from 0.2% per year at GMFCS level I to 9.5% at GMFCS level V. Radiographic hip surveillance from age 1 to 2 years was recommended for non-ambulatory children with CP on a regular basis. Current management options for hip displacement in children with CP include reconstructive procedures such as varus derotation osteotomy of the proximal femur,6 preventive surgery such as adductor releases,7 or a combination of both.8 A large recently published study7 demonstrated that the success of preventive surgery for hip displacement was directly related to GMFCS level. ‘Success’ was defined as the absence of subsequent surgical procedures during the study period of 7 years and a migration percentage of less than 50%. The success rate was 32%. However, the success rate was predicted by GMFCS level, with 94% at GMFCS level II decreasing to 14% at GMFCS level V. Finally, the question remains as to when the hip is stable or unstable in patients with CP. The data from current studies support the fact that hips in children with CP on a high functional level (GMFCS levels I, II, and III) are usually stable, or easily made so – but that hips in non-ambulatory children with CP (GMFCS levels IV and V) are usually not stable! Hip surveillance is important and needs to start by the age of 2 years in non-ambulatory children. The main goal of systematic hip screening is to prevent hip dislocation. Future research, based on the understanding of the biomechanics of the proximal femur, should focus on specific management guidelines for each GMFCS level or at least for ambulatory and non-ambulatory children with CP.

Bilateral Peroneal Nerve Palsy After Bilateral Hip Osteotomy in a Patient with Multiple Hereditary Exostosis: A Case Report and Review of the Literature.

Osteochondromas are solitary masses that rarely cause pain or other symptoms. However, in cases of multiple hereditary exostoses (MHE) in which many osteochondromas are present, extremity deformity is more common. Surgical excision is considered in situations in which altered bone growth is affecting function or if the osteochondroma causes pain. Osteochondromas that affect the proximal part of the femur are common, reported to be involved in 30% to 90% of cases of MHE1-4, and can affect growth and morphology of both the femur and acetabulum. More specifically, coxa valga deformities have been reported in 25% of patients with MHE5, including femoral neck broadening, femoral anteversion, and valgus deformity together with acetabular dysplasia4,6. Proximal femoral varus-producing osteotomies have been described7. To the best of our knowledge, there have been no reported nerve injuries during a varus-correcting osteotomy of the proximal part of the femur in patients with MHE. However, one report of 164 proximal femoral osteotomies not associated with MHE described peroneal nerve palsies in two patients8. In this report, we examine the case of a young boy treated for proximal femoral valgus deformity in MHE with bilateral varus-producing osteotomy of the proximal part of the femur. We evaluate the surgical complication of bilateral peroneal nerve palsy and discuss the patient’s clinical course, including surgical treatment of the nerve palsies. The patient and his parents were informed that his case would be submitted for publication, and they provided consent. A nine-year-old boy with multiple previous surgical interventions related to MHE had been followed for painful bilateral hip dysplasia and valgus deformity of the proximal part of the femur. The patient had no additional symptoms regarding the lower extremities, and the physical examination demonstrated excellent strength and normal sensation. …

Total Knee Arthroplasty in a Patient With Pseudopseudohypoparathyroidism

Pseudopseudohypoparathyroidism (PPH) is a rare genetic disorder characterized by multiple musculoskeletal anomalies and normal serum calcium, phosphate, and parathyroid hormone levels. Although the musculoskeletal manifestations of PPH are well known, little has been reported on the management of orthopedic problems. We report a case of total knee arthroplasty (TKA) performed in a patient with PPH. To our knowledge, this case is not only unique to the arthroplasty literature but is the first report of its kind. This report illustrates the unique pathoanatomy of PPH, the medical and surgical management required, and a previously unreported musculoskeletal abnormality associated with PPH: synovial osteochondromatosis of the knee. Common musculoskeletal anomalies associated with PPH include shortening/bowing of long bones; shortening of metacarpals, metatarsals, and/or phalanges; exostoses; calcification/ossification of subcutaneous and/or periarticular soft tissues; a thickened calvarium; microcephaly; bony coalitions of the hand; vertebral column abnormalities; cubitus valgus; radius/ulna curvus; coxa vara; coxa valga; and genu valgum. This case is the first to report an association of synovial osteochondromatosis with PPH. Because synovial osteochondromatosis and PPH share a common disorder of soft tissue calcification/ossification, as well as abnormal bone formation, this clinical finding does not seem merely coincidental.

Abnormal growth of the proximal femur due to apophyseal-epiphyseal coalescence resulting in coxa valga—a report of two cases in adolescents

We present 2 cases (male adolescents) with a radiologically evident apophyseal-epiphyseal coalescence in the proximal femur, resulting in a coxa valga with a horizontal growth plate. We discuss the developmental mechanism and possible clinical relevance of this rare phenomenon.

Mechanobiological prediction of proximal femoral deformities in children with cerebral palsy

Children with cerebral palsy (CP) walk with altered gait and frequently exhibit proximal femoral deformities, such as anteversion and coxa valga. The objective of this research was to investigate the effect of specific gait patterns on the femoral morphology in CP. In this study, the mechanobiological principles were implemented on a 3D finite element (FE) model of the proximal femur in order to predict changes in morphology over time in healthy and CP children. This model relies on the assumption that cyclic octahedral shear stress promotes growth and cyclic hydrostatic compressive stress inhibits growth. Growth was simulated over 16 iterations, representing approximately 5 months of growth. The FE model predicts an increase in the femoral anteversion and coxa valga for CP loading conditions when compared with healthy ones. Understanding the role of loading in skeletal morphogenesis may help prevent bone deformities and improve function in children with gait abnormalities.

Total hip arthroplasty for osteoarthritis with coxa valga in multiple exostosis : A case report

Total hip arthroplasty for osteoarthritis with coxa valga in multiple exostosis : A case report

Finite element model of the proximal femur under consideration of the hip centralizing forces of the iliotibial tract

Background The aim of our investigations was the development of a finite element model of the hip joint under consideration of the hip centralizing forces of the iliotibial tract within different femoral neck angles and its influence to the centralizing of the femoral head to the acetabulum. Methods For the development of the finite element model of the femur and the iliotibial tract we utilized the program IDEAS 3D as well as the material/lengthening characteristics of the iliotibial tract. In the following step we developed a hip joint model with different centrum-collum-diaphysis-angles of 115°, 128° and 155° for determination of the IT force and the consequential force on the femoral head. Findings With a coxa vara the force on the femoral head in relation to the physiological centrum-collum-diaphysis-angle and the coxa valga decreased (115° = 1601 N, 128° = 2360 N, and 155° = 2422 N). On the other side the hip centralizing forces of the iliotibial tract within a coxa vara increased in comparison to 128° (physiological) and 155° (valga) (115° = 997 N, 128° = 655,5 N, and 155° = 438 N). Within a coxa valga a higher compressive force on the femoral head and with a coxa vara a decreasing compressive force on the femoral head occurred. Interpretation The clinical relevance consists in the predictability of an increasing or decreasing band wiring effect of the iliotibial tract in reliance to the centrum-collum-diaphysis-angle of the femoral neck and its importance for the displacement osteotomy of the growing hip.

Osteochondritis Dissecans of the Femoral Head

Seven patients with symptomatic osteochondritic lesions of the femoral head are presented. All were male with a mean age of 26 years (16 - 33 years). Two distinct morphologic appearances of the hip joint could be identified. Five patients presented with a coxa valga deformity, four of whom had signs of epiphyseal dysplasia. There were 2 patients whose hips appeared normal apart from the osteochondrontic lesions. In both cases an additional acetabular rim lesion due to a reproducible femoro-acetabular impingement was diagnosed at arthrotomy. This may have acted as the underlying cause of osteochondritis dissecans in these cases. All 7 patients underwent surgical treatment. An intertrochanteric osteotomy (I.O.) alone was performed in 2 patients. Follow-up of these patients at 6.5 and 8.5 years after surgery revealed that the osteochondritic lesions had not healed and one individual remained symptomatic. In the remaining 5 patients, treatment consisted of femoral head dislocation and screw fixation of the osteochondritic lesion. This was combined with an I.O. in two of these patients for coxa valga and osteoplasty of a broad femoral neck in 2 other patients. All lesions had healed at an average follow-up of 4.3 years (2 - 8.5 years). Three patients were asymptomatic and 2 patients had minor residual pain. No progressive osteoarthritic changes or signs of avascular necrosis of the femoral head were observed.

CT Reveals a High Incidence of Osseous Abnormalities in Hips with Labral Tears

Acetabular labral tears are being diagnosed with increasing frequency and there is a growing consensus that these tears rarely occur in the absence of osseous abnormalities. We therefore determined the presence of structural abnormalities in patients with acetabular labral tears using a standardized CT protocol. We evaluated 135 consecutive patients with labral tears diagnosed by MRI with CT scans of the symptomatic hip. The CT scans were evaluated in a standardized fashion to determine acetabular and femoral pathomorphologic features. Acetabular evaluation included version measurements and anterior and lateral center-edge angles. Femoral parameters evaluated included version, alpha angle, and neck-shaft angle. One hundred twenty-two (90%) of the 135 hips had structural abnormalities. One hundred two (76%) had an alpha angle greater than 50°, 18 (13%) had femoral version less than 5°, 22 (16%) had femoral version greater than 25º, and five (4%) had coxa valga. Fifty-eight (43%) patients had acetabular retroversion and five (4%) had a lateral center-edge angle less than 20º. Of the 58 patients with acetabular retroversion, 23 had isolated cranial retroversion, 12 had isolated central retroversion, and 23 had combined cranial and central retroversion. Sixty-seven of the 121 hips (55%) with bony abnormalities had a combination of abnormalities. Ninety percent of patients with labral tears had structural abnormalities seen on CT scans. These structural abnormalities frequently occur in combination, and understanding these underlying morphologic features of the hip can help guide treatment. Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Morphometric Analysis of the Femur in Cerebral Palsy

The cause of hip disorder in cerebral palsy (CP) has been thought to involve muscle imbalance, flexion, and adduction contracture of the hip joint, acetabular dysplasia, and femoral growth abnormalities. The aim of this study was to quantitatively evaluate the 3-dimensional femoral geometry and subluxation/dislocation of the hip in spastic CP using 3D-CT reconstructed images of the pelvis and the femur, focusing on the femoral growth abnormalities in CP. Between June 2006 and September 2009, 186 hips in 93 bilateral spastic CP patients, including spastic diplegia (SD) in 73 patients and spastic quadriplegia (SQ) in 20 patients, who had not received any surgical treatment, were investigated using 3D-CT at our hospital. There were 59 boys and 34 girls with an average age of 5.3 years (range: 2.6 to 6.8 y). As an index for the femoral geometry, the neck-shaft angle, the femoral anteversion, and the femoral offset were 3-dimensionally measured. The center of the acetabulum and the femoral head were determined to calculate the CT migration percentage as the distance between these centers divided by the femoral head diameter. To elucidate the factors related to hip subluxation/dislocation, the relationships between the neck-shaft angle, the femoral anteversion, the femoral offset, and the CT migration percentage were investigated. The mean neck-shaft angle was 150.4+/-9.4 degrees (range: 129.4 to 173.2 degrees). The mean femoral anteversion was 44.4+/-13.6 degrees (range: 5.8 to 84.0 degrees). The mean CT migration percentage was 22.4+/-22.7% (range: 3 to 129%). There was positive correlation between the CT migration percentage and the neck-shaft angle (r=0.49). Hips with large CT migration percentage tended to show coxa valga. There was an inverse correlation between the neck-shaft angle and the femoral offset (r=-0.90), but no correlation between the CT migration percentage and the femoral anteversion (r=0.26), between the femoral offset and the femoral anteversion (r=-0.25), or between the neck-shaft angle and the femoral anteversion (r=0.23). The neck-shaft angle, the femoral anteversion, and the CT migration percentage were significantly larger, and the femoral offset was significantly smaller, in patients with the Gross Motor Functional Classification System (GMFCS) level IV/V (nonwalking children) and SQ type, than in patients with GMFCS level II/III (mostly walking children) and SD type. The 3-dimensional femoral geometry in CP patients can be analyzed quantitatively using 3D-CT regardless of the abnormal spastic posture. Our data indicate that 3-dimensional evaluation is accurate and useful for analysis of the femur and acetabulum in CP, and that the extent of coxa valga and femoral anteversion is more severe in the patients with GMFCS level IV/V and SQ type. Level IV.

Preliminary effect of proximal femoral nail antirotation on emergency treatment of senile patients with inter-trochanteric fracture

Objective To retrospectively analyse the clinical outcome of emergency treatment of senile intertrochanteric fractures with proximal femoral nail antirotation (PFNA). Methods From September 2008 to March 2009, 35 senile patients with intertrochanteric fracture, aged from 65 to 92 years with an average age of 76.5 years, were treated with PFNA within 24 hours after injury. There were 10 type I fractures, 19 type II and 6 type III according to upgraded Evans-Jensen classification system. All patients were complicated with osteoporosis, and 19 patients had preexisting internal medical diseases. According to the rating scale of disease severity by the American Society of Anesthesiologists (ASA), there were 9 grade I, 14 grade II, 8 grade III, and 4 grade IV. Results The duration for operation ranged from 45 to 73 minutes with an average of 57.6 minutes. The volume of blood loss during operation ranged from 50 to 120 ml with an average of 77.5 ml. Patients could ambulate 2–4 days after operation (mean 3.5 days). Hospital stay was 4–7 days (mean 5.3 days). Full weight bearing time was 10–14 weeks (mean 12.8 weeks). During hospitalization period, there was no regional or deep infection, hypostatic pneumonia, urinary tract infection and bedsore except for 2 cases of urine retention. All cases were followed up with an average period of 12.3 months, and bone healing achieved within 15–18 weeks (mean 16.6 weeks). No complications such as delayed union, coxa vara or coxa valga, screw breakage or backout occurred and only 2 cases had trochanter bursitis because of thin body and overlong end of the antirotated nail. According to the Harris grading scale, the results were defined as excellent in 21 cases, good in 9 cases and fair in 5 cases, with the excellent and good rates of 85.7%. Conclusion The emergency treatment of senile inter-trochanteric fracture with proximal femoral nail antirotation has the advantages of minimal invasion, easy manipulation, less blood loss, shorter length of stay, less complications, and the preliminary clinical effect is satisfactory.

Long term results of Intramedullary Nailing in childhood femur fractures

Objective: To evaluate the impact on bone growth of intramedullary nailing of femur using Küntscher technique in childhood. Methods: 18 patients who had undergone Küntscher intramedullary nailing were analyzed as they have grown to adulthood. Growth of each lower limb was compared using predefined clinical and radiological parameters. Results: Patient ages at the time of evaluation, ranged from 21 to 30 years and the follow up length 12 to 16 years. Clinical examination noted 10 normal patients and 8 patients with anomalies, among them 6 were less than 12 years old at the time of intervention. Six patients had lengthening; 4 had atrophy of the thigh and 7 patients had coxa valga of operated limb. All patients with coxa valga had undergone the intervention before the age of 12 years. Conclusion: intramedullary nailing using Küntschter nails to treat femoral fractures in children may have some long terms sequelae. Therefore it is advisable not to use this technique in children less than 12 years old. Key words: intramedullary nailing, children, growth plate, femur.

Validity and Reliability of Measuring Femoral Anteversion and Neck-Shaft Angle in Patients with Cerebral Palsy

Increased femoral anteversion and coxa valga are common in patients with cerebral palsy. The purpose of the present study was to determine the validity and reliability of the methods that are commonly used to measure the proximal femoral geometry in patients with cerebral palsy. Thirty-six consecutive patients (mean age, eleven years; range, five to twenty years) with cerebral palsy were enrolled in the present study. The validity and the interobserver reliability of the physical examinations performed by three examiners were determined by comparing the results of a trochanteric prominence angle test, hip internal rotation measurements, and hip external rotation measurements (all with the patient in the prone position) with the amount of femoral anteversion on two-dimensional computed tomography. Validity and intraobserver and interobserver reliability were assessed by comparing the neck-shaft angle on the anteroposterior internal rotation radiograph of the hips with that on the multiplanar reformatted computed tomographic image. The trochanteric prominence angle test showed excellent concurrent validity (R = 0.862, p < 0.001) and reliability (intraclass correlation coefficient, 0.809). Hip internal rotation also showed good concurrent validity (R = 0.787, p < 0.001) and excellent reliability (intraclass correlation coefficient, 0.889), whereas hip external rotation appeared to be unsuitable for predicting femoral anteversion. The neck-shaft angle on the anteroposterior internal rotation radiograph of the hips showed excellent concurrent validity (R = 0.892, p < 0.001) and reliability (intraclass correlation coefficient, 0.912). A physical examination for determining femoral anteversion and the neck-shaft angle as measured on the internal rotation radiograph of the hips appear to be clinically relevant methods for evaluating the proximal femoral geometry and version in patients with cerebral palsy. Computed tomographic examination can probably be replaced by physical examination and an anteroposterior internal rotation radiograph of the hips for patients with stable hips who are able to walk.

Multiple osteochondromas in the archaeological record: a global review

Multiple osteochondromas is an inherited autosomal dominant condition of enchondral bone growth. The paper undertakes the first synthesis study of the 16 known cases of the condition that have been identified in the international palaeopathological record. It also includes information derived from two newly discovered cases of the disease in two adult male individuals recovered from the Medieval cemetery at Ballyhanna, Co. Donegal, Ireland. The formation of multiple osteochondromas is the best known characteristic of the disease but it also involves the development of a suite of orthopaedic deformities. These deformities, which include disproportionate short stature, inequality of bone length, forearm deformities, tibiofibular diastasis, coxa valga of the hip and valgus deformity of the knee and ankle, are discussed in relation to the archaeological cases. Numerous synonyms for the disease have been used within the various publications produced by palaeopathologists, and this can generate confusion among readers. As such, the paper recommends that in future palaeopathologists should follow the guidance of the World Health Organization and use the term multiple osteochondromas when discussing the disease.

Valgus Slipped Capital Femoral Epiphysis: Prevalence, Presentation, and Treatment Options

Valgus slipped capital femoral epiphysis (SCFE), defined as posterolateral slippage of the proximal femoral epiphysis on the metaphysis, is an uncommon occurrence. The purpose of this study was to review our institution's experience with valgus SCFE to better describe its prevalence, clinical presentation, and treatment. Radiographs of patients undergoing treatment of SCFE between 1996 and 2008 were reviewed. Valgus SCFE was identified by increased prominence of the lateral femoral epiphysis relative to the lateral femoral neck and an increased anteroposterior physis shaft angle. We identified 12 patients (16 hips) with valgus SCFE and compared them with 123 cases identified as classic posteromedial SCFE. The prevalence of valgus SCFE at our institution was 4.7% (12 of 258 patients). Significant differences between patients with valgus SCFE and those with classic SCFE were found for age at presentation (mean 1.1 y younger, P=0.033), sex (58% female vs. 28% male, P=0.044), and classification as atypical SCFE (42% vs. 3%, P<0.001), respectively. Four patients in the valgus group had pituitary and growth hormone dysfunction, and 1 was diagnosed with Stickler syndrome. Hips of valgus patients had a significantly higher mean femoral neck shaft angle (154.3 degrees) as compared with classic SCFE patients (140.5 degrees) (P<0.001). Difficulty placing hardware for in situ fixation was noted in 5 of 11 valgus cases, with 1 case complicated by articular surface penetration and chondrolysis. Valgus displacement often presents with a relatively normal appearance on anteroposterior radiographs. Valgus SCFE may be associated with obesity, coxa valga, hypopituitarism, and Stickler syndrome. Posterolateral displacement of the femoral epiphysis makes in situ fixation of valgus SCFE more difficult, due to the necessity of a more medial starting point. Case series, Level IV.

Hip centralizing forces of the iliotibial tract within various femoral neck angles

A contentious issue in the literature is the function and the biomechanical properties of the iliotibial tract. On account of this fact the aim was to take a measurement about the hip centralizing forces of the iliotibial tract by using a custom-made hip prosthesis with adjustable femoral neck angles and lengths in an anatomic model. By increasing the collodiaphyseal (CCD) angle (coxa valga) a higher load of the hip joint results. Decreasing the CCD angle (coxa vara) leads to a lower load of the hip joint. In the case of lengthening the femoral neck we saw a considerable increase of the forces along the femoral neck. Furthermore, we registered intraoperatively the subligamentous forces of the iliotibial tract in the height of the greater trochanter to analyse the axial forces into the acetabular cavity. The iliotibial tract showed increasing forces within adduction as well as decreasing forces within abduction of the hip joint. The clinical relevance consists of the predictability of the increasing or decreasing tension band wiring effect of the iliotibial tract in correlation to the CCD angle. The measurement gives the clinical users a benchmark for the expected subligamentous forces of the iliotibial tract and the resulting hip centralizing forces.

Hereditary Multiple Exostoses of the Hip

To assess the radiographic features of 36 hips with hereditary multiple exostoses (HME). Hip parameters of 12 males and 6 females (36 hips) aged 2 to 28 years with HME were assessed using anteroposterior radiographs. The recorded features included the sites of osteochondromas, the femoral head/neck ratio, the Reimer's migration percentage, Sharp's acetabular angle, the centre edge angle, the femoral neck-shaft angle, and degenerative changes. 15 of the 18 patients were asymptomatic; 3 complained of pain (2 underwent excision or bone biopsy); no lesion was malignant. Osteochondromas were most commonly located in the femur followed by the ilium; only one was intra-articular. 32 hips had coxa valga; 26 had an abnormal Reimer's migration percentage; 17 had an abnormal Sharp's acetabular angle; 12 had an abnormal centre edge angle; 32 had an abnormal femoral neck-shaft angle; and 6 had degenerative changes. Acetabular and femoral dysplasia as well as subluxation are common in patients with HME. Borderline subluxated hips and those with marked coxa valga and/or acetabular dysplasia should be closely monitored to determine the need for surgery in the future. Subluxated hips should be operated on early, particularly in children and symptomatic adults.

Stickler syndrome associated with slipped capital femoral epiphysis

We report a case of Stickler syndrome associated with slipped capital femoral epiphysis. A 10-year-old male subsequently developed left thigh pain without any provoking cause. Three days after, when he swung a bat, marked left hip pain developed. Radiograph showed a slipped capital femoral epiphysis. At the age of 1 year, he underwent surgery due to cleft palate. The visual acuity was bilaterally decreased, and a diagnosis of bilateral retinal/vitreous degeneration had been made. Radiograph on the normal side showed coxa valga. According to clinical symptoms and past history, diagnosis of Stickler syndrome associated with slipped capital femoral epiphysis was made. On the day of the first visit, surgery was performed for slipped capital femoral epiphysis. No intentional reduction was performed. After gentle protective traction, in situ fixation was performed with 6.5 mm cannulated cancellous screw. After 5-month nonweight-bearing, weight-bearing was initiated, and full-weight bearing was achieved after 1 month. MRI 6 months after the operation showed no bone necrosis, and lateral radiography confirmed bone union.

Die hüftkopfzentrierenden Kräfte des Tractus iliotibialis bei variierendem Schenkelhalswinkel

Concerning the biomechanical properties of the iliotibial tract different opinions can be found in the literature. Due to this fact it was the aim of this study to take measurements about the hip centralising forces of the iliotibial tract in a neutral position as well as in abduction, adduction and flexion of the hip joint at different femoral neck angles by using a custom-made hip prosthesis. By using a custom-made measuring endoprothesis with the capability for adjusting different femoral neck angles and lengths and, furthermore, by measuring the intra- and subligamentous forces at the height of the greater trochanter, we measured the forces for validating the influence of the iliotibial tract for hip joint centralisation. By increasing the CCD angle (coxa valga) a higher load on the hip joint results. By decreasing the CCD angle (coxa vara) a lowering of the coxalfemoral load results. Flexion of the knee joint leads to a decrease of the iliotibial tract tension. By extension of the knee joint and resulting tightening of the iliotibial tract, a triplication of the forces at the femoral neck was measured. Flexion of the hip joint exerted a ventralising of the iliotibial tract with an initial decrease of the centralising hip forces. Subligamentous measurement of the iliotibial tract showed increasing forces upon adduction as well as decreasing forces upon abduction of the hip joint. In the investigations about the forces with various femoral neck lengths, we saw a considerable increase by lengthening the femoral neck and resulting higher forces in the acetabulum. The clinical relevance of these results concerns the predictability of the in- or decreasing tension band wiring effect of the iliotibial tract in correlation to the CCD angle and the direction of motion of the hip joint. The measurements give the clinical users a benchmark for the expected subligamentous forces of the iliotibial tract and the resulting hip centralising forces. The influence of the lengthening of the femoral neck for the hip centralising forces clarifies the importance of the iliotibial tract when planning displacement osteotomies or hip joint replacement.

Transient monoparesis after blade plate removal in a Hutchinson–Gilford progeria syndrome patient: a case report

Treatment of patients with Hutchinson-Gilford progeria syndrome (HGPS) is based on the abnormalities of accelerated aging that affect the healing processes, combined with a fragile cardiovascular status. A classic HGPS case, of Korean ancestry, previously treated for severe coxa valga with bilateral varus osteotomies using blade plate fixation is presented. Complications over the blade plate area required removal of the hardware, after which the patient showed right-sided hypertonicity--determined to be a cerebrovascular accident. Subsequently, the patient returned almost completely to her presurgical neurologic status. Perioperative planning for HGPS patients should include risks that are typically considered in the planning for geriatric patient care.