Focal Deficiency Research Articles

Verlängerung des kongenital kurzen Femurs (PFFD) mittels Hybridfixateur unter Einbeziehung des Kniegelenks

A major problem in lengthening a short femur in proximal focal deficiency of the femur (PFFD) is the development of contractures and dislocation of the hip and knee joint. The knee joint is particularly prone to dislocation because of the cruciate ligament insufficiency associated with PFFD. Axis deviations also need specific attention. In four patients (age 2.5-11 years) with PFFD (PAPPAS class III in one patient and VII in three patients), five femoral lengthenings with mechanical axis corrections were performed by the callotasis technique using a hybrid fixation system (Monotube/Triax) connecting the femur and the tibia with a fixed hinged knee joint to protect the knee against contracture and dislocation. All patients retained their hip and knee function. Hip flexion contracture during lengthening may make inclusion of the hip joint into the fixation system necessary, but was not carried out in the four patients presented. Four consecutive lengthenings of the femur with focal deficiency were carried out under protection by a hinged knee bridging external fixator. A dislocation could be prevented in all patients. We consider that such a system could be used during these lengthening procedures.

Proximal Femoral Focal Deficiency as a Manifestation of Antley-Bixler Syndrome: A Case Report

We report a case of the Antley-Bixler syndrome in an 11-year-old girl. She presented with bilateral proximal femoral focal deficiency, right clubfoot, left radiohumeral synostosis, bilateral ear hypoplasia, cleft palate, tongue tie, missing teeth, congenital heart disease, a pelvic kidney with hydronephrosis, and mental retardation. Proximal femoral focal deficiency has never been reported before as a manifestation of Antley-Bixler syndrome. Her mother was exposed to radiation during an intravenous urogram done in the first trimester of pregnancy. Exposure to radiation has not been implicated as a cause of Antley-Bixler syndrome.

Acetabular Dome Retroversion: Radiological Appearance, Incidence and Relevance

Interest in acetabular version arose from the study of unstable developmental dysplastic hips (DDH). Initial studies and clinical observations described the dysplastic hip as being excessively anteverted. Doubts on this view arose from analysis of complications such as persistent posterior subluxation after acetabular reorienting procedures. Computed tomography fails to determine conclusively whether or not the dysplastic acetabulum is abnormally anteverted. Controversy evolves from different methods of measuring and from the fact that the acetabular opening gradually spirals from mild anteversion proximally to increasing anteversion distally. This renders the measurement of version dependent on pelvic inclination and the level of the transverse CT scan slice. On an orthograde pelvic radiograph, both pelvic inclination and rotation can be controlled. Therefore, acetabular version is best estimated based on the relationship of the anterior and posterior acetabular rims to each other on an orthograde pelvic radiograph. Acetabular retroversion has been found to be a characteristic feature of specific hip disorders such as post-traumatic dysplasia, proximal femoral focal deficiency and bladder exstrophy. In addition, acetabular retroversion has been described in DDH as well as in dysplastic hips in the context of neuromuscular and genetic disorders. Iatrogenic acetabular retroversion can also result from corrective pelvic osteotomies in childhood. Finally, retroverted acetabula may be found in otherwise nondysplastic hips. The relevance of acetabular retroversion is twofold: First, it demands a more individualized approach to acetabular dysplasia because the presence of retroversion will affect the manner in which the corrective osteotomy should be done. Second, the long-term effect of acetabular retroversion is harmful.

Comparison of the Complication Rates Between First and Second (Repeated) Lengthening in the Same Limb Segment

The purpose of this study is to compare the incidence and types of complications in children who are undergoing first and second (repeated) lengthenings of the same bone. This is a retrospective review of 11 children (12 limbs) who underwent limb lengthenings of the same bone twice. There were 7 femoral and 5 tibial repeated lengthenings. Diagnoses included congenital femoral deficiency or proximal femoral focal deficiency in 6 patients, fibular hemimelia in 2, achondroplasia in 2, and tibial hypoplasia in 1. Mean age was 8.5 years for the first lengthening and 11.5 years for the second lengthening. There were 2.2 complications per lengthening for the first procedure and 1.5 for the second lengthening. There were 5 major and 22 minor complications for the first lengthening and 1 major and 17 minor complications for the second lengthening, none of these data were found to be statistically different. The healing index was 1.3 +/- 0.43 months per cm first lengthening and 2.2 +/- 1.7 cm for the second lengthening. This study did not demonstrate a significantly higher rate of complications with repeated lengthening of the same limb, although the time in the fixator for the second lengthening was longer and the degree of lengthening less.

Accessory scrotum with multiple skeletal abnormalities

Accessory scrotum is very uncommon. Here we report a 5-year old Caucasian boy presenting with an accessory scrotum localized to the left side of the pubic area. The penis and the primary scrotum were completely normal, containing two dependent testicles. On the right side of the body there was type B proximal femoral focal deficiency and there was also diastasis of the symphisis pubis. As observed in this case, abnormalities of two different embryological organ systems (accessory labioscrotal fold and proximal femoral focal deficiency) may occur concurrently at the same intrauterine time point as part of an overall embryologic mesenchymal disorder.

Acetabular dome retroversion: radiological appearance, incidence and relevance

Interest in acetabular version arose from the study of unstable developmental dysplastic hips (DDH). Initial studies and clinical observations described the dysplastic hip as being excessively anteverted. Doubts on this view arose from analysis of complications such as persistent posterior subluxation after acetabular reorienting procedures. Computed tomography fails to determine conclusively whether or not the dysplastic acetabulum is abnormally anteverted. Controversy evolves from different methods of measuring and from the fact that the acetabular opening gradually spirals from mild anteversion proximally to increasing anteversion distally. This renders the measurement of version dependent on pelvic inclination and the level of the transverse CT scan slice. On an orthograde pelvic radiograph, both pelvic inclination and rotation can be controlled. Therefore, acetabular version is best estimated based on the relationship of the anterior and posterior acetabular rims to each other on an orthograde pelvic radiograph. Acetabular retroversion has been found to be a characteristic feature of specific hip disorders such as post-traumatic dysplasia, proximal femoral focal deficiency and bladder exstrophy. In addition, acetabular retroversion has been described in DDH as well as in dysplastic hips in the context of neuromuscular and genetic disorders. Iatrogenic acetabular retroversion can also result from corrective pelvic osteotomies in childhood. Finally, retroverted acetabula may be found in otherwise nondysplastic hips. The relevance of acetabular retroversion is twofold: First, it demands a more individualized approach to acetabular dysplasia because the presence of retroversion will affect the manner in which the corrective osteotomy should be done. Second, the long-term effect of acetabular retroversion is harmful.

Proximal femoral focal deficiency in a newborn

Proximal femoral focal deficiency in a newborn

N-terminally extended surfactant protein (SP) C isolated from SP-B-deficient children has reduced surface activity and inhibited lipopolysaccharide binding.

In both humans and mice, a deficiency of surfactant protein B (SP-B) is associated with a decreased concentration of mature SP-C and accumulation of a larger SP-C peptide, denoted SP-C(i), which is not observed under normal conditions. Isolation of hydrophobic polypeptides from the lungs of children who died with two different SP-B mutations yielded pure SP-C(i) and showed only trace amounts of mature SP-C. Determination of the SP-C(i) covalent structure revealed a 12-residue N-terminal peptide segment, followed by a 35-residue segment that is identical to mature SP-C. The SP-C(i) structure determined herein is similar to that of a proposed late intermediate in the processing of proSP-C, suggesting that SP-C(i) is the immediate precursor of SP-C. In bronchoalveolar lavage fluid from transgenic mice with a focal deficiency of SP-B, SP-C(i) was detected in the biophysically active, large aggregate fraction and was associated with membrane structures that are typical for a large aggregate surfactant. However, unlike SP-C, SP-C(i) exhibited a very poor ability to promote phospholipid adsorption, gave high surface tension during cyclic film compression, and did not bind lipopolysaccharide in vitro. SP-C(i) is thus capable of associating with surfactant lipids, but its N-terminal dodecapeptide segment must be proteolytically removed to generate a biologically functional peptide. The results of this study indicate that the early postnatal fatal respiratory distress seen in SP-B-deficient children is combined with the near absence of active variants of SP-C.

Morphologic characteristics of acetabular dysplasia in proximal femoral focal deficiency.

A retrospective radiographic analysis of the acetabulum of 13 patients (14 hips) with proximal femoral focal deficiency (PFFD), clinically classified into Gillespie and Torode type 1, was performed to better understand its morphologic features at maturity. The version of the proximal part of the acetabulum was determined quantitatively and qualitatively. All 14 hips showed residual or borderline acetabular dysplasia with a mean lateral centre-edge angle of -1.5degrees and an acetabular index of 30degrees. The acetabular dome was retroverted in all hips and averaged -24degrees. Acetabular deficiency compared with the opposite side, while not present with respect to the anterior wall, averaged 12% with respect to the posterior wall. Dysplasia associated with type 1 PFFD is therefore fundamentally different from that seen in developmental residual hip dysplasia. Clinically, despite radiographic evidence of dysplasia, 57% were without clinical manifestations of hip pathology. This may be due to a number of factors including age of last radiograph, severity of dysplasia, and the decreased functional demand placed on the hip in some individuals with associated malformations. For the symptomatic hip, the posterior insufficiency and relative retroversion of the acetabular dome should be taken into consideration in planning reorientation procedures. This can help to prevent problems of persistent subluxation or acetabulo-femoral impingement following reconstruction.

Morphologic characteristics of acetabular dysplasia in proximal femoral focal deficiency

A retrospective radiographic analysis of the acetabulum of 13 patients (14 hips) with proximal femoral focal deficiency (PFFD), clinically classified into Gillespie and Torode type 1, was performed to better understand its morphologic features at maturity. The version of the proximal part of the acetabulum was determined quantitatively and qualitatively. All 14 hips showed residual or borderline acetabular dysplasia with a mean lateral centre–edge angle of −1.5° and an acetabular index of 30°. The acetabular dome was retroverted in all hips and averaged −24°. Acetabular deficiency compared with the opposite side, while not present with respect to the anterior wall, averaged 12% with respect to the posterior wall. Dysplasia associated with type 1 PFFD is therefore fundamentally different from that seen in developmental residual hip dysplasia. Clinically, despite radiographic evidence of dysplasia, 57% were without clinical manifestations of hip pathology. This may be due to a number of factors including age of last radiograph, severity of dysplasia, and the decreased functional demand placed on the hip in some individuals with associated malformations. For the symptomatic hip, the posterior insufficiency and relative retroversion of the acetabular dome should be taken into consideration in planning reorientation procedures. This can help to prevent problems of persistent subluxation or acetabulo-femoral impingement following reconstruction.

Patellofemoral Arthritis in a Fused Knee With Proximal Femoral Focal Deficiency

A patient with proximal femoral focal deficiency (PFFD) who underwent knee fusion without patella resection and Boyd amputation at age 2.5 years developed severe symptomatic patellofemoral arthritis 10 years later that required excision of her patella. A survey among the 780 members of the Pediatric Orthopaedic Society of North America with a 58% response rate showed that 8 of the 355 pediatric orthopaedists who perform knee fusion without patellar removal in PFFD have experienced problems with patellofemoral degeneration, whereas 57 surgeons excise the patella either routinely or occasionally. Nine respondents reported they use the patella as graft to enhance knee arthrodesis. Twenty-eight surgeons reported no experience in management of patients with PFFD, 3 prefer leg-lengthening procedures as the treatment of choice, and 16 encountered problems related to prosthetic fitting. Patellar resection may be considered when knee fusion and foot amputation are performed in children with PFFD to anticipate for late patellofemoral arthritis.

Treatment of Longitudinal Deficiency Affecting the Femur: Comparing Patient Mobility and Satisfaction Outcomes of Syme Amputation Against Extension Prosthesis

Patients with proximal focal femoral deficiency or longitudinal deficiency affecting the femur were selected from a large regional center. Twenty-eight such patients were identified and were divided into two groups depending on how their condition was managed. Group 1 had opted for the surgical approach of ankle disarticulation (Syme amputation) and the fitting of an above-the-knee prosthesis. The patients in group 2 had been managed in a nonsurgical fashion using an extension prosthesis. They were asked about their level of mobility using the recognized Locomotor Index and their overall satisfaction using self-designed questions. The two groups' scores were similar for mobility whether using their prosthesis or not, but group 1 had lower satisfaction scores than group 2. Current opinion advocates the use of surgery in the management of proximal focal femoral deficiency because it is believed to have better cosmetic and functional results, but in the authors' comparison similar scores for mobility were shown. The nonsurgical extension prosthesis was associated with fewer musculoskeletal and residual limb problems, fewer problems with public transport, and greater satisfaction than Syme amputation. Overall, this small study suggests that the nonsurgical approach is preferable.

Proximal femoral focal deficiency. Results of conservative and surgical treatment, critical analysis and indications

The treatment of proximal focal femoral deficiency (PFFD) has always been a challenge for the pediatric orthopaedic surgeon. Multiple conservative and surgical approaches have been recommended with frequently unsatisfactory results. We reviewed the medical records of 22 patients seen between 1981 and 1990, and evaluated the results and complications of 3 different treatments administered according to the extent of leg length discrepancy. Of the 22 patients, 5 with the greatest leg length discrepancy were treated with hip stabilization (group A), 14 patients had leg lengthening (group B) and 3 patients had conservative treatment and orthosis (group C). The average follow-up period was16.8 years (range, 10–22 years). Mean age of the patients at treatment was 5.8 years (range, 1–12 years) in group A, 8.4 years (range, 4–16 years) in group B and 3.3 years (range, 1-6 years) in group C. Roentgenograms showed stable hips (Fixsen and Lloyd-Robert's type I) in only 2 of 5 patients from group A and 7 of 14 patients of group B. The remaining were unstable hips (Fixsen and Lloyd-Robert's types II and III). In group B the Wagner apparatus was used in 12 cases, Orthofix in 1 case and Lazo-Canadell in 1 case. 6 patients in group B underwent more that one lengthening. The mean residual shortenings in groups A, B and C were, respectively, 12.2 cm (range, 2–27), 11.5 cm (range, 1–20) and 18.1 cm (range, 4–27). The patients were evaluated in reference to gait, range of motion at knee and hip levels, stability of the hip and knee and residual shortening on an original scoring scale. Group A showed 60.0% of good results (3 of 5 cases), group B 64.3% (9 of 14 cases) and group C 66.6% (2 of 3 cases). Among patients who sustained to femoral lengthening (group B), complications were osteitis (6 cases), angular deformity (3 cases), pseudoarthrosis (1 case), and fracture (1 case); group A presented 2 cases of pseudoarthrosis while group C had no complications. This experience confirms that the treatment of the patient must be individualized with reference to age, presence or absence of stable hip and other anomalies of the limb. The contribution we make for further evaluations is a proposed new scoring system.

Cytochrome c oxidase deficiency in the muscle of patients with zidovudine myopathy is segmental and affects both mitochondrial DNA- and nuclear DNA-encoded subunits.

Zidovudine (AZT) can induce a mitochondrial disorder associated with mitochondrial (mt) DNA depletion affecting skeletal muscle, heart, and liver. Zidovudine myopathy is characterized by ragged-red fibers and partial cytochrome c oxidase (COX) deficiency. We evaluated at a single fiber level the expression of COX II (mtDNA-encoded) and COX IV (nuclear DNA-encoded) subunits in 12 HIV-infected patients with zidovudine myopathy. We also evaluated COX activity on longitudinal muscle sections in one patient. In all patients, evaluation of the expression of COX II and COX IV subunits showed focal deficiency. All fibers negative for COX II or COX IV were negative by COX histochemistry; 32-92% (median 61%) of COX-negative fibers were negative for COX II antigens, and 7-58% (median 28%) were negative for COX IV antigens. One hundred and thirty-nine of 317 COX-negative fibers 139 (43.8%) were selectively negative for COX II; 28 of 317 (8.8%) COX-negative fibers were selectively negative for COX IV. A study of longitudinal distribution of COX activity demonstrated that COX deficiency was segmental with blurred borders, as previously observed in patients with myoclonus epilepsy with ragged-red fibers. We conclude that proteins encoded by mtDNA are predominantly, but not exclusively, involved in zidovudine myopathy. Our results confirm the value of single muscle fiber evaluation in the assessment of mitochondrial abnormalities related to zidovudine.

Contrasts in gait mechanics of individuals with proximal femoral focal deficiency: Syme amputation versus Van Nes rotational osteotomy.

Lower-limb kinematics and kinetics during preferred and fast speeds of walking were measured in persons with proximal femoral focal deficiency to compare outcomes after Syme amputation (nine subjects) with those after Van Nes rotational osteotomy (10 subjects). Subjects with a Van Nes rotational osteotomy and full tibial rotation (seven subjects) demonstrated prosthetic knee function during stance as they were able to support a flexed-knee posture at both speeds and produced greater knee-extensor moments at preferred speeds as compared with the Syme group (p < 0.05). Nonprosthetic limb compensatory mechanics were significantly exacerbated in subjects with a Syme amputation compared with the Van Nes group: (a) stance-phase vaulting, resulting in greater inappropriate ankle-power generation at both walking speeds, (b) excessive hip-extensor moments at fast speeds, (c) excessive hip-power absorption and generation at both speeds, and (d) excessive knee-joint power generation at both speeds (p < 0.05). The improved gait after Van Nes rotational osteotomy is one factor that should be considered when making clinical decisions for children with proximal femoral focal deficiency.

Contrasts in Gait Mechanics of Individuals with Proximal Femoral Focal Deficiency: Syme Amputation Versus Van Nes Rotational Osteotomy

Contrasts in Gait Mechanics of Individuals with Proximal Femoral Focal Deficiency: Syme Amputation Versus Van Nes Rotational Osteotomy

Treatment of Proximal Femoral Focal Deficiency by Using a Hybrid Orthotic and Prosthetic Design

Treatment of Proximal Femoral Focal Deficiency by Using a Hybrid Orthotic and Prosthetic Design

Proximal Femoral Focal Deficiency(PFFD): More Than An Abnormal Hip.

As the name implies, proximal femoral focal deficiency (PFFD) is a failure in development of the proximal femur and acetabulum of varying degrees. This article reviews the classification schemes with illustrated examples. Clinical findings, associated anomalies, imaging, and treatment are discussed. Patients are classified by radiographs, often changing classes as the patientÕs skeleton matures. Magnetic resonance imaging (MRI) can aid in earlier and more accurate classification. The classification scheme exists to predict future function and the role of surgical intervention.

Treatment of Proximal Femoral Focal Deficiency by Using a Hybrid Orthotic and Prosthetic Design

Treatment of Proximal Femoral Focal Deficiency by Using a Hybrid Orthotic and Prosthetic Design

Total hip arthroplasty in an adult with proximal femoral focal deficiency

A 40-year-old woman with isolated unilateral proximal femoral focal deficiency presented with 2 years of gradually increasing left hip pain that interfered with her activities of daily living. A total hip arthroplasty was performed through a posterior approach. At 12 months, she had minimal discomfort about the hip, a markedly increased level of activity, and improved gait, and she required no ambulatory aids. This procedure is cautiously recommended for use in selected patients with proximal femoral focal deficiency.