Femoral Physis Research Articles

Age-Related Changes on Mri Of Posterior Cruciate Ligament Morphology in A Skeletally Immature Population

Background:Magnetic resonance imaging (MRI) analysis of the developmental morphology of the anterior cruciate ligament (ACL) in pediatric and adult patients has led to the identification of anatomical risk factors for injury and optimization of surgical reconstruction. Similar work regarding pediatric posterior cruciate ligament (PCL) morphology is limited despite increasing incidence of PCL injury and rising favorability of surgical reconstruction.Purpose:The aim of this study was to describe age-dependent changes in ligamentous and osseous anatomy of the pediatric PCL by comparison of MRI measurements across pre-adolescent and adolescent age groups.Methods:Sixty patients with a knee MRI and wrist radiographs who were seen from 2008 to 2018 at a single tertiary care center were randomly selected from a departmental database and categorized into skeletal age groups (ages 7-9 years, 10-12 years, and 13-15 years) with 20 patients in each group (Table 1). Skeletal age was determined from wrist radiographs and patients with a PCL injury or prior knee surgery were excluded. Twelve dimensions of the PCL substance or its osseous attachment sites were measured on MRI by two independent reviewers. Pairwise comparisons were conducted between the youngest and intermediate, as well as the intermediate and oldest skeletal age groups.Results:There was statistically significant growth across skeletal age groups in femoral physis width (p<0.001), tibial physis width (p<0.001), and medial femoral condyle (MFC) width (p<0.001) and height (p<0.001). Growth in femoral PCL height (p=0.02), femoral PCL footprint to femoral physis height (p=0.004), tibial PCL insertion width (p<0.001), tibial PCL footprint to tibial physis height (p<0.001), and tibial epiphysis height (p=0.003) and width (p<0.001) was only statistically significant between the youngest and intermediate groups. Only MFC height (p=0.03) and width (p=0.001), femoral PCL height (p=0.05), and tibial physis width (p=0.02) were significantly larger in the oldest compared to the intermediate group. Intrasubstance PCL width did not demonstrate significant age-related change (Table 2). Intrarater reliability for all measurements was excellent; interrater reliability was variable.Conclusions:Morphological changes of the pediatric PCL and associated osseous anatomy vary by skeletal age throughout childhood and adolescence. These changes were most pronounced in preadolescents with open physes (ages 7-12 years) compared to adolescents with closing physes (ages 13-15 years), who demonstrated slowed or plateaued growth in most dimensions. These skeletal age-dependent transformations of the PCL and surrounding osseous anatomy may guide surgical planning and inform injury risk prediction and prevention in this active population.Table 1.Cohort characteristics. (N=60)Table 2.MRI measurement summary by skeletal age group.

Traumatic Hip Dislocation Associated with Proximal Femoral Physeal Fractures in Children: A Systematic Review.

Traumatic hip dislocation might lead to serious complications and a poor outcome. Fortunately, it is a rare condition in pediatric patients. The purpose of this study is to establish and describe the complications caused by hip dislocations associated with transphyseal femoral neck fractures. Therefore, we conducted a literature review that resulted in 11 articles, including 32 patients, older than 10 years of age, suffering from traumatic hip dislocation associated with a transphyseal femoral neck fracture. We presented a case series of three patients with hip fracture-dislocation treated in our clinic that were also evaluated and included in the study. For the 35 patients included in the study group, the percentage of avascular osteonecrosis after hip fracture-dislocation was 88.57%. Traumatic hip dislocation associated with transphyseal femoral neck fracture is a rare condition and has a poor prognosis because of the high incidence of femoral head avascular necrosis (AVN). Reduction should be attempted within six hours the from injury, but this may not minimize the risk of AVN if transphyseal separation occurs. The approach may influence the development of AVN; lateral approach of the hip with great trochanter osteotomy seems to have the lowest number of cases of AVN.

A Novel Model of Hip Femoroacetabular Impingement in Immature Rabbits Reproduces the Distinctive Head-Neck Cam Deformity

Background: Femoroacetabular impingement (FAI) is a leading cause of hip pain in young adults and often leads to degenerative osteoarthritis (OA). A small animal model of hip deformities is crucial for unraveling the pathophysiology of hip OA secondary to FAI. Purposes: To (1) characterize a new minimally invasive surgical technique to create a proximal femoral head–neck deformity in a skeletally immature rabbit model and (2) document the effect of an injury to the medial proximal femoral epiphysis on head–neck morphology at 28 days after the injury. Study Design: Controlled laboratory study. Methods: Six-week-old New Zealand White rabbits (n = 10) were subjected to right hip surgery, with the left hip used as a control. An epiphyseal injury in the medial femoral head was created using a 1.6-mm drill. Hips were harvested bilaterally at 28 days after surgery. Alpha and epiphyseal shaft angles were measured on radiographs. Alpha angles at the 1- and 3-o’clock positions were measured on the oblique axial plane of micro–computed tomography images. Bone bar formation secondary to growth plate injuries was confirmed using alcian blue hematoxylin staining. Results: All hips in the study group showed a varus–type head-neck deformity, with lower epiphyseal shaft angles on anteroposterior radiographs versus those in the control group (133°± 8° vs 142°± 5°, respectively; P = .022) and higher epiphyseal shaft angles on lateral radiographs (27°± 12° vs 10°± 7°, respectively; P < .001). The mean alpha angles in the study group were higher at both the 1- (103°± 14° vs 46°± 7°, respectively; P < .002) and 3-o’clock (99°± 18° vs 35°± 11°, respectively; P < .002) positions than those in the control group. Alcian blue hematoxylin staining of all hips in the study group indicated that the injured physis developed a bony bar, leading to growth plate arrest on the medial femoral head. Conclusion: The proposed model led to growth arrest at the proximal femoral physis, resulting in a femoral head–neck deformity similar to human FAI. Clinical Relevance: Our novel small animal model of a femoral head–neck deformity is a potential platform for research into the basic mechanisms of FAI disease progression and the development of disease–modifying therapies.

Is there a persistent capital femoral epiphysis growth after screw fixation for slipped capital femoral epiphysis?

ABSTRACTFemoral neck screwing during child development is controversial. The objective of this study was to evaluate the residual growth of the capital femoral physis after screw fixation. This retrospective study included children aged younger than 12 years treated for slipped capital femoral epiphysis (SCFE) with a single percutaneous partially threaded cannulated screw. The children were followed up for at least 1 year. Some patients also underwent prophylactic contralateral screwing. Preoperative, immediate postoperative and final follow-up X-rays were evaluated to determine the degree of slippage, pin–joint ratio (PJR), neck–pin ratio (NPR), number of threads crossing the physis, neck–shaft angle (NSA), screw–physis angle and screw position in the physis. We included 17 patients (29 hips: 18 SCFE and 11 prophylactic) with a mean age of 10.1 years (range: 7.1–11.9 years) at the time of surgery. Significant evolution of radiological growth parameters of the proximal femoral physis was noted during a mean follow-up of 2.4 years (range: 1–4.3 years). The mean PJR significantly decreased from 7.3 to 6.0, the mean NPR significantly decreased from 106 to 96 and the mean number of threads beyond the physis decreased from 3.3 to 1.8. The mean NSA decreased by 6.5°, from 139° to 132.5°. Persistent capital femoral epiphysis growth occurs after screw fixation. The NSA significantly decreases over time but remains within the physiological limits. Level of evidence: IV (case series)

Pediatric neglected distal femoral fracture with growth arrest.

Introduction and importanceDistal femoral growth plate fracture is one of the most common growth plate fractures in the pediatric age, and associated with growth disturbance risk. Consequences that may arise are hindered growth, irreversible decrease in range of motion, instability, angular deformity and neurovascular issues. Fractures of the lateral condyle show a higher risk of developing sequelae compared to the medial side.Case presentationCorrective osteotomy of the distal femur was performed in patient with history of femoral fracture which undergone an ORIF procedure for the shaft at the previous hospital, while the lateral condyle fracture was treated conservatively. We did close wedge osteotomy medially and transferred the bone fragment to the lateral side as an open wedge to lengthen the lateral cortex. The leg-length discrepancy was reduced from 5 to 2 cm even though subsequent deformities may possibly occur.Clinical discussionThe management approach for fracture of distal femoral physis can be done conservatively or surgically. Unfavorable outcomes from the conservative approach gave more reasons to opt for a surgical approach. The growth plate location should be considered when deciding which level of osteotomy is best and the fixation points in younger patients. When physeal bars are formed due to the fracture stress on the growth plate, the treatment is based on the patient's age and the bar's size.ConclusionFractures of the distal femur involving a growth plate in children should not be considered a trivial case, and a comprehensive treatment plan should be coordinated.

Outcomes and Survivorship at a Median of 8.9 Years Following Hip Arthroscopy in Adolescents with Femoroacetabular Impingement: A Matched Comparative Study with Adults.

Because of the unique theoretical surgical risks, including osteonecrosis, acute iatrogenic slipped capital femoral epiphysis, and epiphyseal injury, the optimal treatment strategy for femoroacetabular impingement (FAI) in growing adolescents has yet to be established. The aim of this study was to compare the clinical outcomes of primary arthroscopic treatment of FAI in growing adolescents with a matched adult group. Patients with FAI who underwent arthroscopic treatment with a minimum follow-up of 2 years were included. Patients with previous ipsilateral hip surgery, an Outerbridge grade of ≥3, a preoperative Tönnis grade of ≥2, or evidence of dysplasia (lateral center-edge angle of <25°) were excluded. Eligible patients who were ≤19 years old and whose proximal femoral physis had not yet closed were matched to adult (20 to 40-year-old) counterparts in a 1:1 ratio by sex, body mass index, and time of surgery. For the adolescents, cam resection was performed with a physeal-sparing approach. Outcome scores, including the modified Harris hip score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), and HOS-Sports-Specific Subscale (HOS-SSS), were prospectively collected. Of the 196 eligible adolescents, 157 (80%) were pair-matched to adult controls, with a median postoperative follow-up of 8.9 and 6.6 years, respectively. Fourteen (9%) of the adolescents required revision hip arthroscopy compared with 18 adults (11%) (p = 0.46). No patient in the adolescent group had conversion to a total hip arthroplasty (THA), while 3 in the adult group had a THA (p = 0.25). For adolescents without subsequent hip surgery, the median mHHS improved from 59 preoperatively to 96 postoperatively; the HOS-ADL, from 71 to 98; and the HOS-SSS, from 44 to 94 (p < 0.001), which were significantly higher postoperative scores than those of the matched adults (p < 0.05) despite similar or inferior baseline scores. No complications were found during the office visit or at the final follow-up. Hip arthroscopy performed with a physeal-sparing approach for FAI in growing adolescents is safe and effective and yields superior clinical outcomes compared with those in a matched adult group. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Neridronate for transient osteoporosis of the hip in a child

Transient osteoporosis of the hip (TOH) is usually reported in middle-aged men or during pregnancy as a benign self-limiting condition. Nevertheless, its impact on quality of life in terms of pain and disability is considerable. Also, it can lead to insufficiency fractures or, more rarely, evolve into osteonecrosis. This condition is anecdotally described in the pediatric age and very little is known about how it may affect the growing bone. We herein describe a case of TOH in a 10-year-old child treated at our pediatric rheumatology service and summarize the pediatric cases of TOH previously reported in literature. There are two points of interest in our case report, the first one being the unusual complication of TOH with a femoral physis fracture and the second the complete recovery after the off-label therapy with bisphosphonates. We suggest that interventional medical treatment could be considered in selected cases of juvenile TOH, to prevent any possible irreversible damage on the femoral physis. As far as we know, this is the first report of neridronate employment in children affected by TOH.

Improved epiphyseal socket placement with intraoperative 3D fluoroscopy: a consecutive series of pediatric all-epiphyseal anterior cruciate ligament reconstruction.

Disturbance of the growth plate during all-epiphyseal anterior cruciate ligament reconstruction (ACLR) socket placement is possible due to the undulation of the distal femoral physis and proximal tibial physis. Therefore, it is important to obtain intraoperative imaging of the guide wire prior to reaming the socket. The purpose of this study was to investigate the effect of the use of 3D intraoperative fluoroscopy on socket placement in patients undergoing all-epiphyseal ACLR. It was hypothesized that 3D imaging would allow for more accurate intraoperative visualization of the growth plate and hence a lower incidence of growth plate violation compared to 2D imaging. Patients under the age of 18 who underwent a primary all-epiphyseal ACL reconstruction by the senior authors and had an available postoperative MRI were retrospectively reviewed. Demographic data, surgical details, and the distances between the femoral socket and distal femoral physis (DFP) and tibial socket and proximal tibial physis (PTP) were recorded. Patients were split into two groups based on type of intraoperative fluoroscopy used: a 2D group and a 3D group. Interrater reliability of radiographic measurements was evaluated using intraclass correlation coefficient (ICC). Seventy-two patients fit the inclusion criteria and were retrospectively reviewed. 54 patients had 2D imaging and 18 patients had 3D imaging. The mean age at time of surgery was 12.3 ± 1.5years, 79% of patients were male, and 54% tore their left ACL. The mean time from surgery to postoperative MRI was 2.0 ± 1.1years. The ICC was 0.92 (95% CI 0.35-0.98), indicating almost perfect interrater reliability. The mean difference in distance between the tibial socket and the PTP was significantly less in the 2D imaging group than the 3D imaging group (1.2 ± 1.7mm vs 2.5 ± 2.2mm, p = 0.03). The femoral and tibial sockets touched or extended beyond the DFP or PTP, respectively, significantly less in the 3D group than in the 2D group (11% vs 43%, p < 0.000, 17% vs 65%, p < 0.000). There was a significantly increased distance from the PTP and decreased incidence of DFP violation with use of 3D intraoperative imaging for all-epiphyseal ACLR socket placement. Surgeons should consider utilizing 3D imaging prior to creating femoral and tibial sockets to potentially decrease the risk of physis violation in these patients. III.

Developmental features of the canid proximocaudal femur.

We continued direct morphological studies of the canid coxofemoral joint, considering early-life spatial relationships around the locus of the proximocaudal joint capsule insertion. Our primary goal was to elucidate the postnatal developmental gross anatomy of the proximocaudal femur, among juveniles across Canidae. From an original database of 267 independent (museum) specimens from 11 canid taxa and 1 hybrid taxon, we identified 29 ancient or modern candidate juvenile specimens (nine taxa and one hybrid taxon). Based on optimal ability to recognize landmarks, the best photographic data were categorized into five groups of four each (n= 20). The data groups approximated early juvenile, early-mid juvenile, mid-juvenile, mid-late juvenile; and young adult stages. In this descriptive photographic essay, we demonstrate the developmental spatial proximity among (a) the dorsal meeting of the respective lateral and medial extensions from the growth centers of the femoral head and greater trochanter; (b) the caudodorsal aspect of the coxofemoral joint capsule attachment; (c) a segment of the proximocaudal femoral shaft physis; and (d) an eventual associated mineralized prominence. The latter occurs frequently but not universally, suggesting natural population variability across taxa. Across taxa and juvenile age categories, the morphology thus supports developmental conservation among ancient and modern Canidae. The biomechanical and biological cause-effect implications are not yet clear. For zoological purposes, we apply the term postdevelopmental mineralized prominence to the residual caudolateral surface feature. We extend the original anatomical work of Morgan in zoological and phylogenic arenas, using direct observation of cleared skeletal specimens.

Freeman-Sheldon Syndrome with Stiff Knee Gait - A Case Report.

Introduction:Freeman-Sheldon syndrome (FSS), also known as the distal arthrogryposis (DA) type 2A, is a rare congenital anomaly. We report a unique case of the DA type 2A with mixed clinical features and the unusual presentation of bilateral congenital dislocation of the knee but had unassisted stiff knee gait.Case Report:A 5-year-old female child presented to the clinic with the complaint of inability to bend both knees since birth. She had an unassisted bipedal gait, but could not squat, cross-leg sit, run, and climb stairs without assistance. Her youngest brother had a similar presentation but succumbed to death at the age of 5 months due to respiratory distress. Clinical features were in the favor of FSS. Her serum creatinine kinase level was normal and the electromyography of bilateral tibialis anterior and abductor pollicis brevis was not suggestive of the myotonia. Radiograph of the skull showed cooper beaten skull appearance whereas bilateral pelvis with the hip showed following changes in the right hip; decrease femoral epiphysis height, horizontal proximal femoral physis, and the coxa brevia. She was initially managed conservatively by weekly stretching, manipulation, and casting. As a result, she could flex her knee up to 20°. Although the quadricepsplasty might be helpful for the persistent extension deformity, there was marked quadriceps weakness which could make it harder for the child to stand and walk. In addition, the abnormal muscle physiology in FSS may result in unfavorable outcomes after the surgery. Moreover, a consideration of the surgical aspect is not free of risks which include difficult endotracheal intubation, vein access, and malignant hyperthermia.Conclusion:FSS is a rare congenital anomaly that should be differentiated from another syndrome of the close resemblance, Sheldon Hall syndrome and Schwartz Jampel syndrome which are other rare autosomal recessive disorders characterized by myotonia and the chondrodysplasia. Conservative management has still a role in bilateral knee involvement especially if the patient is an independent walker.

Reduction and Fixation of Unstable Slipped Capital Femoral Epiphysis: A Case Report

Background: Slipped capital femoral epiphysis, is a common condition of the proximal femoral physis that leads to slippage of the epiphysis relative to the metaphysis. Diagnosis can be confirmed with radiographs of the hip. Treatment is usually percutaneous screw fixation. Objective: To study the outcome and complications of closed reduction and internal fixation by percutaneous screw fixation in unstable slipped capital femoral epiphysis. Patient and methods: Our case report is 11 years old obese male patient with history of progressive right hip pain for 10 days prior to presentation to the hospital. BMI was 36.1 kg/m2. Patient presented with right hip pain and inability to bear weight, radiological evaluation confirmed right hip unstable slipped capital femoral epiphysis that required emergency in situ fixation Result: close follow up of the patient to 6 months, patient regain full functional activity, he achieved a complete range of motion of the right hip with good outcomes and with no complications. The goal in such injuries is to achieve a stable hip joint with gradual rehabilitation to reach a good functional outcome Conclusion: Slipped capital femoral epiphysis occurs in adolescent age group, more affecting male and obese patient, and they are idiopathic in the majority of cases. The goal of treatment in such patients is to achieve a stable hip joint with gradual rehabilitation to reach the optimal functional outcomes

The morphogenesis of porcine femoral head mammillary processes: A structural mechanism of biomechanical stability.

The capital femoral physis is a growth plate located between the head of the femur and femoral neck, which forms a temporary joint where growth plate cartilage is converted to bone by endochondral ossification. The bone-cartilage-bone interface develops a unique radial pattern of interdigitating mammillary processes that interlock the femoral head with the metaphysis, increasing biomechanical stability. The arrangement of these mammillary processes may not be a random occurrence and likely serves to provide mechanical mechanisms to enhance biomechanical stability. In this study, we provide a qualitative and quantitative analysis of porcine femoral head mammillary processes and focus on the analysis of six key points of development: the epiphyseal tubercle, epiphyseal cupping, growth plate slope angles, expansion of the epiphyseal subchondral bone plate, epiphyseal elongation, and the emergence of smaller, radially arranged mammillary processes. We introduce a metric of surface roughness analysis to quantify mammillary processes and apply it to analyze the development of the observed radial pattern of peripheral mammillary processes from birth to adolescence. We hypothesized that these processes develop to form a radial pattern with some degree of periodicity beginning relatively early in development of the joint and increase in prominence with age and weight of the animal. These findings may have important implications in the early diagnosis and treatment of the hip disorder slipped capital femoral epiphysis (SCFE). Underdevelopment of femoral head mammillary processes may reduce joint stability and could be a risk factor in SCFE.

Defining the rate of, and factors influencing, radiographic progression of osteoarthritis of the canine hip joint.

This study aimed to define the rate of progression of radiographic osteoarthritis (OA) of the canine hip joint and to describe factors affecting this progression. Dogs that underwent unilateral total hip replacement (THR) were reviewed for the evaluation of radiographic appearance of the non-operated hip joint over time. Standard extended ventrodorsal hip radiographs were taken preoperatively and postoperatively. All images were anonymized, randomized and scored using three different methods. The mean daily change between evaluations was calculated in each individual dog, and the effect of sex, age, body weight, open/closed status of the proximal femoral physis, preoperative severity of OA, time after surgery and their interactions, were investigated as potential influencing factors. After reviewing the medical records, 163 dogs (468 images) met the inclusion criteria. Consistent across the three scoring systems, radiographic progression of OA was greater in younger (open physis) and spayed female dogs. A subset of seven patients (4.3%) had a faster progression of OA and was considered outliers. No dog was rated as outlier by all three scoring systems. The rate of progression of radiographically assessed coxofemoral OA varies greatly, but is faster in younger, spayed female dogs. Unusually fast progression occasionally occurs.

Growth Modulation by Stimulating the Growth Plate: A Pilot Study

This study investigates the ability of low-intensity pulsed ultrasound (LIPUS) or direct injection of recombinant growth hormone (rGH) to stimulate local growth of long bones. In a randomized controlled animal trial, healthy immature rabbits were allocated to 1 of the following 4 conditions: epiphyseal rGH periosteal injection, transdermal LIPUS, saline periosteal injection, or no treatment. New bone deposition was labeled with calcein at days 1 and 18, and microscopic measurements of growth were conducted by blinded observers. Statistically significant differences in growth were observed between the LIPUS and rGH stimulated legs compared with contralateral control legs (35% p = 0.04 and 41% p = 0.04, respectively); whereas no difference was observed between the 4 control groups (p = 0.37). There was no evidence of physeal bar formation, suggesting that direct injection of rGH and application of LIPUS around the distal femoral physis in rabbits may have a positive effect on microscopic growth without short-term adverse sequelae.

Anatomic and Biomechanical Properties of Flat Medial Patellofemoral Ligament Reconstruction Using an Adductor Magnus Tendon Graft: A Human Cadaveric Study

Background: In contrast to the majority of existing techniques for reconstruction of the medial patellofemoral ligament (MPFL), the technique described in this article uses the adductor magnus muscle tendon to gain a flat, broad graft, leaving its distal femoral insertion intact, and does not require drilling within or near the femoral physis. It also allows for soft tissue patellar fixation and could facilitate anatomic MPFL reconstruction in skeletally immature patients. Purpose: To evaluate the anatomic and structural properties of the native MPFL and the adductor tendon (AT), followed by biomechanical evaluation of the proposed reconstruction. Study Design: Descriptive laboratory study. Methods: The morphological and topographical features of the AT and MPFL were evaluated in 12 fresh-frozen cadaveric knees. The distance between the distal insertion of the AT on the adductor tubercle and the adductor hiatus, as well as the desired length of the graft, was measured to evaluate this graft’s application potential. Load-to-failure tests were performed to determine the biomechanical properties of the proposed reconstruction construct. The construct was placed in a uniaxial testing machine and cyclically loaded 500 times between 5 and 50 N, followed by load to failure, to measure the maximum elongation, stiffness, and maximum load. Results: The mean ± SD length of the AT was 12.6 ± 1.5 cm, and the mean distance between the insertion on the adductor tubercle and adductor hiatus was 10.8 ± 1.3 cm, exceeding the mean desired length of the graft (7.5 ± 0.5 cm) by 3.3 ± 0.7 cm. The distal insertion of the AT was slightly proximal and posterior to the insertion of the MPFL. The maximum elongation after cyclical loading was 1.9 ± 0.4 mm. Ultimately, the mean stiffness and load to failure were 26.2 ± 7.6 N/mm and 169.7 ± 19.2 N, respectively. The AT graft failed at patellar fixation in 2 of the initially tested specimens and at the femoral insertion in the remaining 10. Conclusion: The described reconstruction using the AT has potential for MPFL reconstruction. The AT graft presents a graft of significant volume, beneficial anatomic topography, and adequate tensile properties in comparison with the native MPFL following the data from previously published studies. Clinical Relevance: Given its advantageous anatomic relationship as an application that avoids femoral drilling and osseous patellar fixation, the AT may be considered a graft for MPFL reconstruction in skeletally immature patients.

Mechanics of guided growth of the distal femur for correction of fixed knee flexion deformities: an extra-articular technique.

Anterior distal femoral hemiepiphysiodesis using intra-articular plates for correction of pediatric fixed knee flexion deformities (FKFD) has two documented complications: postoperative knee pain and implant loosening. The aim of this study is to investigate the mechanical properties of a novel extra-articular technique for anterior distal femoral hemiepiphysiodesis in patients with FKFD and to compare them to the conventional technique. Sixteen femoral sawbones were osteotomized at the level of the distal femoral physis and fixed by rail frames to allow linear distraction simulating longitudinal growth. Each sawbone was tested twice: first using the conventional technique with eight plates placed anteriorly just medial and lateral to the femoral sulcus (group A) and then with plates inserted in the proposed novel location at the most anterior part of the medial and lateral surfaces of the femoral condyles with screws in the coronal plane (group B). Gradual linear distraction was performed, and the resulting angular correction was measured. Strain gauges were attached to the plates, and the amount of strain (and equivalent stress) over the plates in response to linear distraction was recorded. The two groups were compared using the Wilcoxon signed-rank test. The amount of angular correction was statistically higher in group B (extra-articular plates) at 5, 10-, and 15-mm of distraction (p < 0.001). As regards stress over the plates, the maximum stress and the area under the curve (sum of all stresses measured throughout the distraction process) were significantly higher when the plates were inserted at the conventional position (group A) (p < 0.001). During anterior distal femoral hemiepiphysiodesis, the fixation of the eight plates in the coronal plane at the anterior part of the femoral condyles may produce a greater amount of correction and a lower degree of stress over the implants as compared to the conventional technique.

Traumatic physeal fractures in cats: a review of 36 cases (2010-2020).

The aim of this study was to describe the demography, aetiology, location and classification of physeal fractures in cats, and to describe their management and outcomes. Clinical records and radiographs of cats referred for management of physeal fractures were retrospectively reviewed. Fractures of the proximal femoral physis were excluded. Descriptive statistics were used to describe signalment, cause of injury, presence of concurrent injuries, fracture description, treatment modality, complications, follow-up, physeal closure, implant removal and outcome. Thirty-four cats with 36 fractures were included, of which 17 affected the distal femur, 11 the distal tibia and fibula, five the distal radius and ulna, two the proximal tibia and one the distal humerus. Salter-Harris classification was type I in 14, type II in 16, type III in two and type IV in four fractures. Thirty-four fractures were treated with primary fixation, and the most common method was crossed Kirschner wires (24/34 fractures). Complications were observed in 14 fractures, of which 12 were minor. At radiographic follow-up, physeal closure was reported in 23 fractures, of which 15 were considered premature. Implant removal was performed in three fractures. Outcome was good in 28, fair in four and poor in two fractures. Fracture of the distal femoral physis was the most common physeal fracture seen. Cats presenting with physeal fractures may be skeletally immature or mature with delayed physeal closure. The rate of physeal closure after fracture repair was relatively high but without apparent impact. The frequency of implant removal was very low, indicating that despite having a physeal fracture repair, most cats did not require a second procedure to remove implants. Overall, internal fixation provided a good outcome in most fractures.

Medial Patellofemoral Ligament Reconstruction Using a Quadriceps Tendon Autograft in a Patient with Open Physes

Recurrent patellar dislocations are correlated with an elevated risk for further patellar dislocations. Chronic patellar instability is a disabling issue for some patients and may require surgical intervention for proper treatment. Risk factors for recurrent dislocations include medial patellofemoral ligament (MPFL) tears, patella alta, trochlear dysplasia, and increased tibial tubercle to trochlear groove distance. Surgical management must be based on a patient’s unique joint pathoanatomy and typically requires medial patellofemoral ligament reconstruction, with or without accompanying procedures such as tibial tubercle osteotomy or sulcus-deepening trochleoplasty. Chronic patellar instability in minors with open growth plates, requires alternative MPFL reconstruction techniques to prevent physeal injury, because of the close proximity of the femoral physis to the MPFL insertion. This article discusses the authors’ preferred technique for surgical treatment of recurrent patellar instability with a medial patellofemoral ligament reconstruction using a quadriceps tendon autograft.

Characteristics of femoroacetabular impingement morphology and relation with skeletal maturity among asymptomatic adolescents

The aim of this study was to analyze presence of the morphological characteristics and prevalence of FAI in asymptomatic adolescents and assess the relation of skeletal maturation with development of FAI morphology. Abdominopelvic computed tomography (CT) of 265 adolescents (9-19 years old) who were admitted to the emergency department between 2011 and 2016 were evaluated retrospectively. Radial reformatted CT images from the femoral neck were created using the multiplanar reconstruction (MPR) method. The femoral neck was divided into 12 segments and alpha angle (AA), femoral head-neck ratio (FHNR) and center-edge angle (CEA) were measured from each segment. Additionally, images were evaluated for the physiological status (open or closed) of the triradiate- cartilage and proximal femoral epiphyses. 204 hips from 102 patients (32 females, 70 males) were retrospectively reviewed. There were 27 (26.5%) patients with cam-type morphology and 18 (17.6%) patients with pincer-type morphologies. No statistically significant difference was detected between the prevalences of cam and pincer morphologies between the two genders. Cam deformity was most frequently seen in anterosuperior segment. All of the patients (100%) with pincer-type morphology and 88% of the patients with cam-type morphology had closed triradiate cartilage, 89% of the patients with cam morphology and 83% with pincer morphology had open proximal femoral physis. Our results showed that prevalence of cam and pincer-type morphology in asymptomatic adolescents is similar to asymptomatic adults. Our findings also indicate that cam- and pincer-type FAI morphologies likely develop during late adolescence after closure of triradiate cartilage and before closure of proximal femoral physis. Level of Evidence - 3.

The Medial Femoral Condyle Flap in the Pediatric Patient.

The use of free flaps from the medial femoral condyle has grown in popularity and is now a workhorse in the reconstruction of skeletal defects. The utility of this technique has not yet been described for the pediatric patient population. The authors present their series of pediatric patients who underwent surgery using a medial femoral condyle free flap or a variant thereof in skeletal reconstruction and demonstrate the efficacy of this technique in this population. A multi-institutional retrospective review of patients aged 18 years or younger who required a medial femoral condyle flap for skeletal reconstruction was undertaken. Operative technique, radiographs, and clinical outcomes were recorded. A novel technique (Innocenti) was used to avoid the distal femoral physis in which a Kirschner wire was placed under fluoroscopic guidance just proximal to the growth plate. Thirteen patients met inclusion criteria, with an average age of 14.7 years (range, 7 to 18 years) and mean follow-up of 28 months (range, 3 to 120 months). Six were skeletally immature at the time of medial femoral condyle harvest, with the last patient having organic bone disease, putting her at risk for pathologic fracture. All 13 patients achieved bony union, and no patients suffered pathologic fractures or physeal injuries; no patients developed length discrepancies. The authors present the first series of corticocancellous medial femoral condyle free flaps in the pediatric population along with a novel technique to avoid injury to the physis in skeletally immature patients. This technique is effective for a variety of skeletal defects or nonunions and is safe for growing patients without causing physeal arrest or growth disturbance. Therapeutic, IV.